REFRIGERATOR

Description

TECHNICAL FIELD

The present disclosure relates to a refrigerator.

BACKGROUND ART

In general, a refrigerator is a home appliance for storing food at a low temperature in a storage space that is covered by a door.

The refrigerator is configured to keep stored food in in a refrigerated state or frozen state by cooling an inside of the storage space using cold air.

The refrigerator may be a side-by-side type refrigerator in which a freezing chamber and a refrigerating chamber are arranged left and right, a top mount type refrigerator in which the freezing chamber is located above the refrigerating chamber, or a bottom freezer type refrigerator in which the refrigerating chamber is located above the freezing chamber.

Typically, an ice maker is provided in the freezing chamber of a refrigerator to make ice. The ice maker receives water supplied from a water source or a water tank in a tray and cools the water to generate ice. The ice generated by the ice maker may be stored in an ice bin.

The ice stored in the ice bin can be discharged through a dispenser provided in the door, or the user can open a freezing chamber door, approach the ice bin, and take out the ice in the ice bin.

A refrigerator is disclosed in Korean Patent Publication No. 10-2021-0026849 that is a prior art document.

A refrigerator of the prior art document may include a freezing chamber, a cooler for supplying cold air to a freezing chamber, and an ice maker provided in the freezing chamber.

The ice maker includes a first tray assembly forming a portion of an ice making cell, which is a space where water is phase-changed into ice by the cold; a second tray assembly forming another portion of the ice making cell; a water supply unit for supplying water to the ice making cell; a heater positioned adjacent to at least one of the first tray assembly or the second tray assembly; and a controller for controlling the heater.

In the case of the prior art document, the controller controls a heating amount of the heater to vary according to a mass per unit height of the water in the ice making cell.

According to the prior art document, an output of the heater may decrease from an initial output and then increase again.

However, as an actual ice freezes, a ratio of ice and water changes and a saturation of bubbles inside water increases, but in the case of the prior art document, an output of the heater is determined by considering only the mass per unit height of the water, so there is a disadvantage in that a deviation in the transparency per unit height of ice increases.

In addition, since an output of the heater decreases in a first half of an ice making process and increases toward a second half of an ice making process, there is a disadvantage that an ice making rate is slowed down by heat of a heater and an ice making time increases.

In the case of the prior art document, the controller controls a heating amount of a heater based on a target temperature of the freezing chamber.

However, there is a disadvantage in that the target temperature is different from an actual temperature of the freezing chamber, it is difficult to accurately control the heater.

In addition, even if a target temperature is set, an actual temperature of the freezing chamber is continuously changing, so there is a disadvantage in that a heater cannot be controlled to accurately reflect an actual temperature of the freezing chamber.

In addition, when a freezing chamber door is opened or a defrosting process is performed, a temperature of the freezing chamber increases, so if a heater is controlled based on a target temperature, there is a disadvantage in that a transparency of the ice generated by an ice maker decreases.

DISCLOSURE

Technical Problem

One embodiment provides a refrigerator in which a variation in transparency of ice generated according to a height is minimized.

Alternatively or additionally, one embodiment provides a refrigerator in which a transparency of ice can be increased while reducing an ice making time.

Alternatively or additionally, one embodiment provides a refrigerator in which a transparency of ice can be increased while reducing a power consumption of a heater.

Alternatively or additionally, one embodiment provides a refrigerator capable of controlling a heater in response to temperature changes in an ice making chamber.

Technical Solution

In one embodiment, a refrigerator may include a storage space. Items may be stored in the storage space. The refrigerator may further include a door to open and close the storage space. The refrigerator may further include a cooling power supply to supply cooling power to the storage space. The refrigerator may further include a tray to form an ice making cell, which is a space where a liquid state object is phase-changed to a solid state object by the cooling power.

The tray may include a first tray to form a portion of the ice making cell. The tray may include a second tray to form another portion of the ice making cell. The second tray may be in contact with the first tray during an ice making process and may be spaced apart from the first tray during an ice separation process.

The refrigerator may further include a water supply to supply water to the ice making cell.

The refrigerator may further include a first temperature sensor to detect a temperature within the storage space. The refrigerator may further include a second temperature sensor to detect a temperature of a liquid state object or a solid state object in the ice making cell.

The refrigerator may further include a heater positioned adjacent to at least one of the first tray or the second tray. The refrigerator may include a controller to control the heater.

The controller may control an ice making process to be performed so that a liquid state object of the ice making cell is phase-changed into a solid state object by the cooling power after a water supply process of supplying water to the ice making cell through the water supply is completed.

The controller may control a heater to be turned on during at least a section while the cooling power supply supplies a cooling power so that a transparency of a solid state object generated in the ice making cell can be improved.

The controller may control an output of the heater to be adjusted within a preset output range so as to maintain an ice making rate of a liquid state object within the ice making cell within a predetermined range that is less than an ice making rate when an ice making process is performed in a state in which a heater is turned off.

The preset output range may be provided between a preset first output line and a preset second output line.

The first output line may be defined as a reference line having a higher output than the second output line in at least one section. The first output line may be defined as a reference line to control so that a temperature of a liquid state object inside the ice making cell is maintained equal to or higher than a first reference temperature. The second output line may be defined as a reference line to control so that a temperature of the liquid object inside the ice making cell is maintained equal to or higher than a second reference temperature, which is a temperature lower than the first reference temperature.

The first output line may include a decrease section of an output of the heater and an increase section of an output of the heater while the ice making process is performed.

The first output line may be defined as a reference line for controlling an output of the heater to be inversely proportional to a mass or volume of a liquid state object per unit height within the ice making cell. The first output line may be defined as a reference line for controlling an output of the heater to be different in a first section and a second section, which are distinguished over time.

The first output line may be defined as a reference line for controlling an output of the heater to be less in the second section than in the first section when a mass or volume of a liquid state object per unit height in the second section becomes greater than in the first section.

The first output line may be defined as a reference line for controlling an output of the heater in the second section to be greater than that in the first section when a mass or volume of a liquid state object per unit height in the second section becomes less than that in the first section.

The second output line may include only sections in which an output of the heater decreases while the ice making process is performed.

In another embodiment, a refrigerator may include a storage space in which items are stored; a door to open and close the storage space; and a cooling power supply to supply cooling power to the storage space. The refrigerator may include a tray to form at least a portion of an ice making cell, which is a space in which water is phase-changed into ice by the cooling power; and a heater positioned adjacent to the tray. The refrigerator may further include a controller to control the heater. The refrigerator may further include a temperature sensor to detect a temperature within the storage space.

The controller may control an ice making process to be performed so that, after a water supply process of supplying water to the ice making cell through the water supply is completed, water in the ice making cell is phase-changed into ice by the cooling power.

The controller may control the heater to be turned on at least a period while the cooling power supply supplies a cooling power so that bubbles dissolved in water inside the ice making cell can move from a portion where ice is made to a liquid state water to generate transparent ice.

The controller may control an output of the heater to a value between a preset first output line and a preset second output line so as to maintain an ice making rate of a liquid state object within the ice making cell within a predetermined range that is less than an ice making rate when an ice making is performed in a state in which a heater is turned off.

While the ice making process is performed, a gap between the first output line and the second output line may increase as time passes.

The controller may be provided to select one of a plurality of ice making modes. In one of the plurality of ice making modes, an output of the heater may be controlled to a value closer to the first output line. In another of the plurality of ice making modes, an output of the heater may be controlled to a value closer to the second output line.

One of the plurality of ice making modes may be defined as a first mode having higher transparency than another of the plurality of ice making modes, and another of the plurality of ice making modes may be defined as a second mode.

One of the plurality of ice making modes may be defined as a first mode having a slower ice making rate than another of the plurality of ice making modes, and another of the plurality of ice making modes may be defined as a second mode.

In further another embodiment, a refrigerator may include a cabinet having a storage space. The refrigerator may further include a door to open and close the storage space. The refrigerator may further include a tray provided in the door or the storage space and including an ice making cell to generate ice. The refrigerator may include a heater to supply heat to the ice making cell; and a controller to control the heater.

In an ice making process, the controller may control the heater to operate with a heating amount between a first heating amount line determined by considering a first factor and a second heating amount line determined by considering a second factor. A heating amount on the first heating amount line may be greater than a heating amount on the second heating amount line. A heating amount on the first heating amount line may decrease from an initial heating amount and then increase. A heating amount on the second heating amount line may decrease from an initial heating amount. The first factor may be a transparency of ice. The second factor may be an ice making rate per unit height or per unit mass or per unit volume within the ice making cell.

The first factor may be a first ice making rate per unit height or unit mass or unit volume within the ice making cell. The second factor may be a second ice making rate per unit height or unit mass or unit volume within the ice making cell. The second ice making rate may be greater than the first ice making rate.

The first factor may be a first transparency of ice. The second factor may be a second transparency of ice. The first transparency may be greater than the second transparency.

A temperature of water in the ice making cell when the heater operates with a heating amount on the first heating amount line may be greater than a temperature of water in the ice making cell when the heater operates with a heating amount on the second heating amount line.

The first heating amount line may include a decreasing section in which a heating amount decreases and an increase section in which a heating amount increases. An absolute value of a slope of a heating amount increase in the increase section may be greater than an absolute value of a slope of a heating amount decrease in the decreasing section.

The second heating amount line may include a section in which a heating amount decrease slope decreases. The second heating amount line may include a section in which a heating amount decrease slope remains constant. A difference between a heating amount on the first heating amount line and a heating amount on the second heating amount line may increase as an ice making process progresses.

The controller can control the heater with a heating amount on a final heating amount line between the first heating amount line and the second heating amount line. A heating amount on the final heating amount line may be decreased from an initial heating amount. The final heating amount line may include a section in which a heating amount decrease slope is maintained constant. The final heating amount line may include a section in which a heating amount decrease slope is decreased. The final heating amount line may include a section in which a heating amount decrease slope is increased. An initial heating amount on the final heating amount line may be close to the first heating amount line. A final heating amount on the final heating amount line may be close to the second heating amount line.

In another embodiment, a refrigerator may include a cabinet to form a storage space; a door to open and close the storage space. The refrigerator may further include a tray provided in the door or the storage space and including an ice making cell to generate ice. The refrigerator may include a heater to supply heat to the ice making cell; and a controller to control the heater. In an ice making process, the controller may determine a heating amount of the heater based on a first heating amount line which is an upper limit heating amount and a second heating amount line which is a lower limit heating amount.

A heating amount of the heater may be determined by a sum of the heating amount x weighting value a on the first heating amount line and a heating amount x weighting value b on the second heating amount line. A sum of the weighting value a and the weighting value b may be 1.

A difference between the upper limit heating amount and the lower limit heating amount may increase as an ice making process progresses. The weighting value a and the weighting value b may vary during an ice making process. In a first half of the ice making process, the weighting value a may be greater than the weighting value b. In a second half of the ice making process, the weighting value a may be less than the weighting value b.

The weighting value a may be a ratio of a volume or mass of water to a total volume or mass of the ice making cell. The weighting value b may be a ratio of a volume or mass of ice to a total volume or mass of the ice making cell.

In further another embodiment, a refrigerator may include a cabinet having a storage space. The refrigerator may further include a door to open and close the storage pace. The refrigerator may further include a tray provided in the door or the storage space and including an ice making cell to generate ice. The refrigerator may further include a heater to supply heat to the ice making cell; and a controller to control the heater.

In an ice making process, the controller may control a heating amount of the heater in a plurality of processes. The controller may control a heating amount of the heater to be decreased stepwise.

I A heating amount decrease slope of the heater may be maintained constant in at a section of the ice making process. A heating amount decrease slope of the heater may be decreased in at least a section of the ice making process. A heating amount decrease slope of the heater may be increased in at least a section of the ice making process.

A heating amount decrease slope of the heater in a first half of the ice making process may be less than a heating amount decrease slope of the heater in a second half of the ice making process.

A heating amount of the heater in a final process among the plurality of processes may be at least ½ of a heating amount of the heater in a first process, which is an initial process among the plurality of processes.

An ice making completion determination process that may be performed after the final process among the plurality of processes may be further included. A heating amount of the heater in the ice making completion determination process may be equal to or less than a heating amount of the heater in the final process. The final process may be end when it is performed for a certain time or may be ended when an amount of water in the ice making cell becomes less than or equal to a reference amount before a lapse of the certain time.

The controller may determine that an ice making is completed when it is determined that a temperature of the ice making cell is reached an ice making completion reference temperature.

The plurality of processes may include a first process performed for a first reference time. The plurality of processes may further include a second process performed for a second reference time after the first process. The plurality of processes may further include a third process performed for a third reference time after the second process. The third reference time may be greater than the first reference time and the second reference time.

A difference between a heating amount of the heater in the second process and a heating amount of the heater in the third process may be greater than a difference between a heating amount of the heater in the first process and a heating amount of the heater in the second process.

In further another embodiment, a refrigerator may include a cabinet to form a storage space; a door to open and close the storage space; a tray provided in the door or the storage space and including an ice making cell to generate ice; a heater to supply heat to the ice making cell; and a controller to control the heater. The controller may control a heating amount of the heater in a plurality of processes.

The controller may control the heater to operate at a first heating amount in a first process among the plurality of processes. In a second process after the first process, the heater may operate at a second heating amount greater than the first heating amount. The heater may be controlled so that a heating amount of the heater decreases as the processes after the second process are performed.

A time for performing the first process may be greater than a time for performing the second process. The first process may be ended when a volume or mass ratio of ice in a total volume or mass of the ice making cell reaches a reference value.

A heating amount of the heater in the last process among the plurality of processes may be less than a heating amount of the heater in the first process. A section in which a heating amount of the heater decreases may include a section in which a heating amount decrease slope of the heater remains constant. A section in which A heating amount of the heater decreases may include a section in which a heating amount decrease slope of the heater increases.

In further another embodiment, a refrigerator may include a cabinet having a storage space. The refrigerator may further include a door to open and close the storage compartment. The refrigerator may further include a tray provided on the door or cabinet and including an ice making cell to generate ice. The refrigerator may further include a heater to supply heat to the ice making cell, and a controller to control the heater.

In an ice making process, the controller may control the heater to operate at a first heating amount in a first ice making section. The controller may control the heater to operate at a second heating amount less than the first heating amount in a second ice making section after the first ice making section.

The controller may control the heater to operate at a third heating amount greater than the second heating amount and less than the first heating amount in the third ice making section after the second ice making section. A second heating amount in the second ice making section may be variable, and an average value of the second heating amount may be less than the first heating amount.

In the second ice making section, the second heating amount may be variable. In the third ice making section, the third heating amount may be variable. An average value of the third heating amount in the third ice making section may be greater than an average value of the second heating amount in the second ice making section.

The first ice making section may be performed for a first reference time, the second ice making section may be performed for a second reference time, and the third ice making section may be performed for a third reference time. A difference value between the first reference time and the second reference time may be greater than a difference value between the second reference time and the third reference time.

The second ice making section may include a decreasing section in which a heating amount of the heater decreases and an increase section in which a heating amount of the heater increases. In the decreasing section, a heating amount decreasing slope of the heater may decrease. In the increasing section, a heating amount increasing slope of the heater may increase.

In the third ice making section, the third heating amount is variable, and a maximum value of the third heating amount of the heater in the third ice making section may be less than the first heating amount. In the third ice making section, the third heating amount of the heater may be increased or decreased stepwise. A heating amount increase slop of the heater in the third ice making section may be decreased. In the third ice making section, a third heating amount of the heater may be maintained constant.

In further another embodiment, a refrigerator may include a cabinet to form a storage space; a door to open and close the storage space; a tray provided in the door or the storage space and including an ice making cell to generate ice; a heater to supply heat to the ice making cell; and a controller to control the heater. In an ice making process, the controller may control the heater to operate at a first heating amount in a first ice making section. The controller may control the heater to operate at a second heating amount less than the first heating amount in a second ice making section after the first ice making section. The controller may control the heater to operate at a third heating amount greater than the first heating amount and the second heating amount in a third ice making section after the second ice making section.

In the second ice making section, the second heating amount may be variable, and an average value of the second heating amount may be less than the first heating amount. In the third ice making section, the third heating amount may be variable. An average value of the third heating amount in the third ice making section may be greater than the first heating amount.

The first ice making section may be performed for a first reference time, the second ice making section may be performed for a second reference time, and the third ice making section may be performed for a third reference time. A difference value between the first reference time and the second reference time may be greater than a difference value between the second reference time and the third reference time.

The second ice making section may include a decreasing section in which a heating amount of the heater decreases and an increasing section in which a heating amount of the heater increases. In the decreasing section, a heating amount decreasing slope of the heater may decrease. In the increasing section, a heating amount increasing slope of the heater may increase.

In the third ice making section, the third heating amount is variable, and a minimum value of the third heating amount of the heater in the third ice making section may be greater than the first heating amount. In the third ice making section, the third heating amount of the heater may be increased stepwise or increased and then maintained constant. In the third ice making section, the third heating amount of the heater may be decreased stepwise, and a decreased final heating amount may be greater than the first heating amount.

In further another embodiment, a refrigerator may include a cabinet having a storage space. The refrigerator may further include a door to open and close the storage space. The refrigerator may further include an ice making chamber provided in the door or the storage space. The refrigerator may further include a tray disposed in the ice making chamber and including an ice making cell to generate ice. The refrigerator may further include a heater to supply heat to the ice making cell, and a controller to control the heater.

In an ice making process, the controller may control a heating amount of the heater based on a temperature of the ice making chamber detected by a temperature sensor. The controller may determine a representative temperature of the ice making chamber based on a temperature of the ice making chamber detected at time intervals. The controller may variably control a heating amount of the heater based on a determined representative temperature.

The representative temperature may be an average temperature of temperatures of the ice making chamber detected at time intervals within a set time range, or a middle temperature between a maximum temperature and a minimum temperature of the ice making chamber within the set time range.

The controller may variably control a heating amount of the heater based on a temperature of the ice making chamber detected at time intervals.

In the ice making process, the heater may be controlled in a plurality of processes. A heating amount of the heater according to a temperature of the ice making chamber in each of the plurality of processes may be determined in advance and stored in a memory. The controller may determine a heating amount of the heater at the current process based on a detected temperature of the ice making chamber.

In each of the plurality of processes, a heating amount of the heater when a temperature of the ice making chamber is low may be greater than a heating amount of the heater when a temperature of the ice making chamber high. In each of the plurality of processes, when a temperature of the ice making chamber increases, a heating amount of the heater may decrease, and when a temperature of the ice making chamber decreases, a heating amount of the heater may increase.

When a temperature of the ice making chamber is maintained within a certain temperature range, a heating amount of the heater in the ice making process may be increased from an initial heating amount and then decreased. When a temperature of the ice making chamber is maintained within a certain temperature range, an initial heating amount of the heater in a first process among the plurality of processes may be greater than a final heating amount of the heater in a final process among the plurality of processes. When a temperature of the ice making chamber is maintained within a certain temperature range, a heating amount of the heater in a first process among the plurality of processes may be less than a heating amount of the heater in a second process after the first process.

A difference between a heating amount of the heater in the first process and a heating amount of the heater in the second process when a temperature of the ice making chamber is maintained in a first temperature range may be different from a difference between a heating amount of the heater in the first process and a heating amount of the heater in the second process when a temperature of the ice making chamber maintained in a second temperature range which is a temperature higher than a temperature of the first temperature range.

When a temperature of the ice making chamber is maintained within a certain temperature range, a heating amount of the heater in the third process performed after the second process may equal to or different from a heating amount of the heater in the first process.

When a temperature of the ice making chamber is maintained in a first temperature range, a heating amount of the heater in the third process may be equal to a heating amount of the heater in the first process. When a temperature of the ice making chamber is maintained in a second temperature range which is a temperature higher than a temperature of the first temperature range, a heating amount of the heater in the third process may be greater than a heating amount of the heater in the first process.

When a temperature of the ice making chamber is maintained within a certain temperature range, a heating amount of the heater in a fourth process performed after the third process may be less than a heating amount of the heater in the third process and a heating amount of the heater in the first process.

In each of a plurality of processes, a difference between a heating amount of the heater when a temperature of the ice making chamber is maintained in a first temperature range and a heating amount of the heater when a temperature of the ice making chamber is maintained in a second temperature range that is a temperature higher than a temperature of the first temperature range may be different from a difference between a heating amount of the heater when a temperature of the ice making chamber is maintained in the second temperature range and a heating amount of the heater when a temperature of the ice making chamber is maintained in a third temperature range that is a temperature higher than a temperature of the second temperature range.

The plurality of processes may be performed for a predetermined reference time for each process. The reference time of a final process among the plurality of processes may be greater than a reference time of each process performed before the final process.

A change pattern in each of the plurality of processes when a temperature of the ice making chamber is maintained in a first temperature range may be different from a change pattern in each of the plurality of processes when a temperature of the ice making chamber is maintained in a second temperature range, which is a temperature higher than a temperature of the first temperature range.

In a first process among the plurality processes, an initial heating amount of the heater may be determined based on an elapsed time from a completion of a water supply to the ice making cell until the heater is turned on when a temperature of the tray reaches an on-reference temperature after a completion of a water supply to the ice making cell.

In a first process among the plurality of processes, an initial heating amount of the heater may be determined based on a temperature of the tray at a time the heater is turned on when the heater is turned on after a water supply to the ice making cell is completed. In the first process among the plurality of processes, an initial heating amount of the heater may be determined based on a temperature of the ice making chamber at a time the heater is turned on.

In further another embodiment, a refrigerator may include a cabinet to form a storage space; a door to open and close the storage space; an ice making chamber provided in the door or the storage space; a tray disposed in the ice making chamber and including an ice making cell to generate ice; a heater to supply heat to the ice making cell; and a controller to control the heater. In an ice making process, the controller may control the heater to operate at a first heating amount in a first ice making section. The controller may control the heater to operate at a second heating amount greater than the first heating amount in a second ice making section after the first ice making section. The controller may control the heater to operate at a third heating amount less than the second heating amount in a third ice making section after the second ice making section. The third heating amount may be varied stepwise.

When a temperature of the ice making chamber is lower than the reference temperature, an initial value of the third heating amount may be equal to the first heating amount. When a temperature of the ice making chamber is higher than the reference temperature, an initial value of the third heating amount may be greater than the first heating amount. A difference between a length of the first ice making section and a length of the second ice making section may be less than a difference between a length of the second ice making section and a length of the third ice making section.

A length of the first ice making section and a length of the second ice-making section may be the same, and a length of the third ice making section may be greater than a length of the first ice making section and a length of the second ice-making section. A change slope of a heating amount of the heater in the third ice making section may be variable.

A change slope of a heating amount when a temperature of the ice making chamber is lower than the reference temperature may be greater than a change slope of a heating amount when a temperature of the ice making chamber is higher than the reference temperature. A heating amount of the heater in each ice making section may be determined based on A temperature of the ice making chamber. When a temperature of the ice making chamber increases in each ice making section, a heating amount of the heater may be decreased. When a temperature of the ice making chamber decreases, a heating amount of the heater may be increased.

In further another embodiment, a refrigerator may include a cabinet to form a storage space. The refrigerator may include a door to open and close the storage space. The refrigerator may include an ice making chamber provided in the door or the storage space. The refrigerator may include a tray disposed in the ice making chamber and including an ice making cell to generate ice. The refrigerator may further include a heater to supply heat to the ice making cell.

The refrigerator may further include a controller to recognize a property related to the refrigerator or an exterior of the refrigerator. In an ice making process, the controller may control a heating amount of the heater based on a recognized property.

The property may include, for example, temperature, pressure, humidity, time, etc. The temperature may include, for example, a temperature of the storage space, a temperature of the ice making chamber, a temperature of a tray, a temperature of a space where an evaporator is disposed, a temperature of a machine room of a refrigerator, an outside temperature, etc. The time may include, for example, a specific time, an elapsed time, etc.

The ice making process may include a first ice making section in which a heating amount of the heater is controlled to include a first heating amount. The ice making process may further include, after the first ice making section is completed, a second ice making section in which a heating amount of the heater is controlled to include a second heating amount.

If a value of the recognized property is included in a first region, the controller may control the first heating amount and the second heating amount to have different values. If a value of the recognized property is included in a second region (for example, 0 degrees) different from the first region, the controller may control the first heating amount (for example, the output is zero) and the second heating amount (for example, a section where the output is zero) to have the same value.

If a value of the recognized property does not reach a reference value, the controller may control the first heating amount and the second heating amount to have different values. When a value of the recognized property reaches a reference value (for example, 0 degrees), the controller may control the first heating amount (for example, a section where the output is zero) and the second heating amount (for example, a section where the output is zero) to have the same value.

In the ice making process, the controller may control a heating amount of the heater to a predetermined value in a case of a first condition, and may control the heater to turn off or not turn on in a case of the second condition that is different from the first condition. The second condition may include at least one of an initial power-on operation, a defrosting operation, or a door load response operation when a value of the recognized property is included in a predetermined range.

A case in which a value of the recognized property is included in a predetermined range may include a case in which an ice making rate in the ice making chamber is lower than a case in which a value of the recognized property is not included in a predetermined range.

The defrosting operation may include at least one of a pre-defrosting cooling operation, a heating operation for defrosting, or a post-defrosting cooling operation. The initial power-on operation may include at least one of a case in which the refrigerator is turned off or a case in which the refrigerator is turned on after being turned off and within a certain time. The door load response operation may include at least one of a case in which the door is opened, a case in which the door is closed after being opened, or a case where a temperature of the storage space rises above a certain range.

In the ice making process, the controller may selectively control to one of processes among a first ice making process in which a heating amount of the heater is varied at least once and a second ice making process in which a heating amount of the heater is varied less than that of the first ice making process.

In the ice making process, the controller may selectively control to one of processes among a first ice making process in which a heating amount of the heater is determined based on at least two or more properties and a second ice making process in which a heating amount of the heater is determined based on a smaller number of properties than that of the first ice making process.

In the ice making process, the controller may selectively control either a first ice making process that controls a heating amount of the heater to a predetermined value, or a second ice making process that controls a heating amount of the heater to a value (for example, including zero) that is less than that of the first ice making process.

In the ice making process, the controller may perform a first ice making process that controls a heating amount of the heater to include a first heating amount based on a value of the recognized property. If a value of the property is changed, a second ice making process that controls a heating amount of the heater to include a second heating amount that is different from the first heating amount may be performed.

The ice making process may include a first ice making section, a second ice making section performed after the first ice making section, and a third ice making section performed after the second ice making section.

The first ice making section may include a section in which the controller controls the heater to operate at a first heating amount. The second ice making section may include a section in which the controller controls the heater to operate at a second heating amount greater than the first heating amount. The third ice making section may include a section in which the controller controls the heater to operate at a third heating amount less than the second heating amount. The third heating amount may be varied stepwise. A change slope of a heating amount of the heater in the third ice making section may be varied.

If a value of the recognized property is included in a first region, the third heating amount may include a value identical to the first heating amount. If a value of the recognized property is included in a second region different from the first region, the third heating amount may include a value greater than the first heating amount.

If a value of the recognized property is included in a first region, the third heating amount may include a value identical to the first heating amount. If a value of the recognized property is included in a second region different from the first region, the third heating amount may include a value equal to or less than the first heating amount.

The first ice making section may include a section in which the controller controls the heater to operate with a first heating amount. The second ice making section may include a section in which the controller controls the heater to operate with a second heating amount less than or equal to the first heating amount. The third ice making section may include a section in which the controller controls the heater to operate with a third heating amount greater than or equal to the second heating amount. The third heating amount may be varied stepwise. A change slope of a heating amount of the heater in the third ice making section may be varied.

If a value of the recognized property is included in a first region, the third heating amount may include a value identical to the first heating amount. If a value of the recognized property is included in a second region different from the first region, the third heating amount may include a value greater than the first heating amount.

If a value of the recognized property is included in a first region, the third heating amount may include a value identical to the first heating amount. If a value of the recognized property value is included in a second region different from the first region, the third heating amount may include a value less than or equal to the first heating amount.

At least one of a length of the first ice-making section, a length of the second ice making section, or a length of the third ice making section may have different values. A difference between a length of the first ice making section and a length of the second ice making section may be less than a difference between a length of the second ice making section and a length of the third ice making section. A difference between a length of the first ice making section and a length of the second ice making section may be greater than or equal to a difference between a length of the second ice making section and a length of the third ice making section. A length of the first ice making section and a length of the second ice making section may be equal to each other. A length of the third ice making section may be greater than a length of the first ice making section and a length of the second ice making section. A length of the third ice making section may be less than or equal to a length of the first ice making section and a length of the second ice making section ..

Advantageous Effect

According to one embodiment, there is an advantage in that a difference in transparency according to a height of ice being generated is minimized.

According to one embodiment, there is an advantage in that an ice making time can be reduced while increasing a transparency of the ice.

According to one embodiment, there is an advantage in that a power consumption of the heater can be reduced while increasing a transparency of the ice.

According to one embodiment, there is an advantage in that the heater can be controlled in response to a temperature change of the ice making chamber.

DESCRIPTION OF DRAWINGS

FIG. 1 is a front view of a refrigerator according to a first embodiment.

FIG. 2 is a drawing showing a state in which one door of the refrigerator of FIG. 1 is separated.

FIG. 3 is a perspective view of a first refrigerating chamber door as viewed from a front side according to a first embodiment.

FIG. 4 is a perspective view of a first refrigerating chamber door as viewed from a rear side according to a first embodiment.

FIG. 5 is a lateral side view of a first refrigerating chamber door according to a first embodiment.

FIG. 6 is a cross-sectional view taken along line 6-6 of FIG. 3.

FIG. 7 is a drawing showing cold air passage in a first refrigerating chamber door according to a first embodiment.

FIG. 8 is a perspective view of a second ice maker according to a first embodiment.

FIG. 9 is a cross-sectional view taken along line 9-9 of FIG. 8.

FIG. 10 is a control block diagram of a refrigerator according to a first embodiment.

FIG. 11 is a flow chart for explaining a process of ice generation in a second ice maker according to a first embodiment.

FIG. 12 is a drawing showing a state in which a water supply is completed at a water supply position.

FIG. 13 is a drawing showing a state in which a second tray is moved to an ice making position.

FIG. 14 is a drawing showing a first parabola, which is an output change line of a transparent ice heater according to a first embodiment.

FIG. 15 is a drawing showing a second parabola, which is an output change line of a transparent ice heater according to a first embodiment.

FIG. 16 is a drawing showing a final output line of a transparent ice heater determined between a first parabola and a second parabola for controlling a transparent ice heater.

FIG. 17 is a drawing showing an output line of a transparent ice heater according to a second embodiment.

FIG. 18 is a drawing showing an output line of a transparent ice heater according to a third embodiment.

FIG. 19 is a drawing showing a change in output of a transparent ice heater in an ice making process according to a fourth embodiment.

FIG. 20 is a drawing showing a change in output of a transparent ice heater in an ice making process according to a fifth embodiment.

FIG. 21 is a drawing showing a step-by-step output of a transparent ice heater in an ice making process according to a sixth embodiment.

MODE FOR INVENTION

FIG. 1 is a front view of a refrigerator according to a present embodiment. FIG. 2 is a drawing showing a state in which one door of the refrigerator of FIG. 1 is separated. FIG. 3 is a perspective view of a first refrigerating chamber door as viewed from a front side according to the present embodiment. FIG. 4 is a perspective view of a first refrigerating chamber door as viewed from a rear side according to the present embodiment.

Referring to FIGS. 1 to 5, a refrigerator 1 of the present embodiment may include a cabinet 2 having a storage space. The refrigerator 1 may further include a refrigerator door to open and close the storage space.

The storage space may include a refrigerating chamber 18. The storage space may optionally or additionally include a freezing chamber 19. As an example, FIG. 2 illustrates that the storage space includes a refrigerating chamber 18 and a freezing chamber 19.

The refrigerating chamber 18 may be opened and closed by one or more refrigerating chamber doors 5. The freezing chamber 19 may be opened and closed by one or more freezing chamber doors 30.

Hereinafter, the refrigerating chamber 18 is described as being opened and closed by a first refrigerating chamber door 10 and a second refrigerating chamber door 20.

At least one of the first refrigerating chamber door 10 or the second refrigerating chamber door 20 may include a dispenser 11 for discharging water and/or ice. Of course, depending on a type of refrigerator, it is also possible for the freezing chamber door 30 to be provided with the dispenser 11.

At least one of the first refrigerating chamber door 10 or the second refrigerating chamber door 20 may include at least one ice maker. Hereinafter, an example of an ice maker being provided in the first refrigerating chamber door 10 will be described. Of course, if necessary, an ice maker may also be provided in the second refrigerating chamber door 20 or the freezing chamber door 30. At this time, the dispenser 11 and the ice maker may be provided in the same door.

Hereinafter, an example will be described in which the first refrigerating chamber door 10 includes a plurality of ice makers. It is not limited thereto, and the second refrigerating chamber door 20 may also include a plurality of ice makers. Of course, it should be noted that a specific control method of an ice maker described below may be applied to an ice maker regardless of a number of ice makers.

In FIG. 2, the refrigerator 1 is exemplarily illustrated as a bottom freezer type refrigerator, but it is to be noted that an idea of the present invention can be equally applied to a side-by-side type refrigerator or a top-mount type refrigerator. In the case of a side-by-side type or top-mount type refrigerator, the freezing chamber door may include a plurality of ice makers or the refrigerating chamber door may include a plurality of ice makers.

The dispenser 11 is disposed at a front side of the first refrigerating chamber door 10, and a portion of the dispensers may be recessed toward rearward to provide a space where a container can be disposed.

The plurality of ice makers may be arranged in a vertical direction. For example, the plurality of ice makers may include a first ice maker 200. The plurality of ice makers may further include a second ice maker 500. At least a portion of the second ice maker 500 may be disposed at a lower side of the first ice maker 200. Of course, the present embodiment does not exclude the plurality of ice makers 200, 500 being arranged in a left-right direction.

The dispenser 11 may discharge at least ice generated in the first ice maker 200. To this end, the first ice maker 200 may positioned higher than the dispenser 11. If the dispenser 11 may discharge ice generated in the second ice maker 500, the second ice maker 500 may positioned higher than the dispenser 11. Or, even if the second ice maker 500 is positioned the same as or lower than the dispenser 11, ice generated in the second ice maker 500 can be transferred to the dispenser 11 by a separate transfer mechanism. As another example, the dispenser 11 may include a first dispenser to discharge ice generated in the first ice maker 200, and a second dispenser to discharge ice generated in the second ice maker.

The first refrigerating chamber door 10 may include an outer case 101 configured to form a front exterior. The first refrigerating chamber door 10 may further include a door liner 102 coupled to the outer case 101. The door liner 102 may open and close the refrigerating chamber 18. In a state in which the outer case 101 is coupled to the door liner 102, an insulating space may be formed in a space between the outer case 101 and the door liner 102. An insulating material may be provided in the insulating space.

The door liner 102 may include a first space 122 in which the first ice maker 200 is disposed. The first space 122 may also be referred to as a first ice making chamber. The door liner 102 may further include a second space 124 in which the second ice maker 500 is disposed. The second space 124 may also be referred to as a second ice making chamber. In the present embodiment, the second ice maker 500 may be omitted, and in this case, the second space 124 may exist. In this case, the second space 124 may function as a door storage space used for a specific purpose. Alternatively, a position of the second ice maker 500 in the present embodiment may vary. Depending on the type of refrigerator, the second ice maker 500 may be positioned in the storage space. In this case, the second space 124 may be present or may be omitted. Alternatively, the first ice maker 200 may be omitted. Alternatively, the second ice maker 500 may be positioned in the first space 122.

The first space 122 may be formed as one side of the door liner 102 is recessed toward the outer case 101. The second space 124 may be formed as one side of the door liner 102 is recessed toward the outer case 101. For example, the second space 124 may be recessed toward the dispenser 11.

The first refrigerating chamber door 10 may include a first ice bin 280 in which ice generated in the first ice maker 200 is stored. The first refrigerating chamber door 10 may further include a second ice bin 600 in which ice generated in the second ice maker 500 is stored. Of course, if the second ice maker 500 is omitted, the second ice bin 600 may also be omitted.

The first ice bin 280 may be received in the first space 122 together with the first ice maker 200. The second ice bin 600 may be received in the second space 124 together with the second ice maker 500.

The first space 122 may be supplied with cold generated from a cooler. The cooler may be defined as a means for cooling the storage space, including at least one of a refrigerant cycle or a thermoelectric element. For example, cold air for cooling the freezing chamber 19 may be supplied to the first space 122. The second space 124 may be supplied with cold generated from a cooler. For example, cold air for cooling the freezing chamber 19 may be supplied to the second space 124.

The refrigerator 1 may include a supply passage 2a that guides cold air of the freezing chamber 19 or cold air of a space where an evaporator that generates cold air for cooling the freezing chamber 19 is disposed to the first refrigerating chamber door 10. The refrigerator 1 may include a discharge passage 2b that guides cold air discharged from the first refrigerating chamber door 10 to the freezing chamber 19 or the space where the evaporator is disposed. The supply passage 2a and the discharge passage 2b may be provided in the cabinet 2.

The first refrigerating chamber door 10 may include a cold air inlet 123a. When the first refrigerating chamber door 10 is closed, the cold air inlet 123a may be communicated with the supply passage 2a. The first refrigerating chamber door 10 may further include a cold air outlet 123b. When the first refrigerating chamber door 10 is closed, the cold air outlet 123b may be communicated with the discharge passage 2b.

The cold air inlet 123a may be formed on one side of the door liner 102. Although not limited, the one side of the door liner 102 may be a side facing a wall where the supply passage 2a is disposed in the refrigerating chamber 18 when the first refrigerating chamber door 10 is closed. The cold air inlet 123a may be disposed to overlap the second space 124, for example, in a horizontal direction. The cold air outlet 123b may be formed on one side of the door liner 102. Although not limited, the one side of the door liner 102 may be a side facing a wall where the discharge passage 2b is disposed in the refrigerating chamber 18 when the first refrigerating chamber door 10 is closed. The cold air outlet 123b may be disposed to overlap the second space 124, for example, in horizontal direction.

A shape of the ice generated from the first ice maker 200 may be the same as or different from a shape of the ice generated from the second ice maker 500. For example, the second ice maker 500 may form spherical ice. Of course, it is also possible for the first ice maker 200 to generate spherical ice. Alternatively, it is also possible for each of the ice makers 200, 500 to generate spherical ice. The “spherical shape” mentioned in this specification means not only a geometrically spherical shape but also a shape similar to a spherical shape.

A transparency of ice generated from the first ice maker 200 may be the same as or different from a transparency of ice generated from the second ice maker 500. For example, a transparency of the ice generated from the second ice maker 500 may be greater than a transparency of the ice formed from the first ice maker 200.

A size (or volume) of ice generated from the first ice maker 200 may be different from a size (or volume) of ice generated from the second ice maker 500. For example, a size or volume of ice generated from the second ice maker 500 may be greater than a size or volume of ice formed from the first ice maker 200.

A structure of the first ice maker 200 for generating ice and a method for separation the generated ice may be the same as or different from a structure of the second ice maker 500 and a method for separation the ice generated from the second ice maker 500 is separated. If the structure and/or the method of the ice makers are different, a shape of the first space 122 where the first ice maker 200 is disposed may be different from a shape of the second space 124 where the second ice maker 500 is disposed.

The one side of the door liner 102 may include a first side portion 102a and a second side portion 102b having different widths in a front-back direction. A width of the second side portion 102b may be formed to be greater than a width of the first side portion 102a. At least one of the cold air inlet 123a or the cold air outlet 123b may be formed on the second side portion 102b of the door liner 102. The second side portion 102b may protrude further toward the refrigerating chamber 18 than the first side portion 102a.

The first refrigerating chamber door 10 may further include a first door130 (or a first space door) that opens and closes the first space 122. The first door 130 may be an insulated door having an insulating material provided therein. The first refrigerating chamber door 10 may further include a second door 132 (or a second space door) that opens and closes the second space 124. The second door 132 may be an insulated door having an insulating material provided therein. Even if the second ice maker 500 is omitted, the second door 132 may exist.

The first door 130 may be rotatably provided on the first refrigerating chamber door 10 by a hinge. The second door 132 may be rotatably provided on the first refrigerating chamber door 10 by a hinge. A rotation direction of the first door 130 and a rotation direction of the second door 132 may be the same or different.

Meanwhile, a basket 136 capable of storing food may be connected to the first door 130 by varying a thickness of the first refrigerating chamber door 10.

Meanwhile, a filter 320 to be described later may be mounted on one side 103 of the first refrigerating chamber door 10, and the filter 320 may be covered by a filter cover 142.

FIG. 6 is a cross-sectional view taken along line 6-6 of FIG. 3. FIG. 7 is a drawing showing cold air passage in a first refrigerating chamber door according to a first embodiment.

Referring to FIGS. 6 and 7, the first refrigerating chamber door 10 may further include a cold air passage for cold air flow. The cold air passage may be formed by a cold air duct, not shown. The cold air duct may be installed, for example, in the door liner 102.

The cold air passage may guide cold air to at least one of the first space 122 or the second space 124.

The cold air passage may include a first cold air passage P1. The first cold air passage P1 may guide cold air supplied from the cabinet 2 to the first space 122. Cold air guided by the first cold air passage P1 may flow toward the first ice maker 200.

The cold air passage may further include a second cold air passage P2. The second cold air passage P2 may guide cold air of the first space 122 to the second space 124. The cold air in a lower portion of the first space 122 may be discharged to the second cold air passage P2. For example, cold air guided by the second cold air passage P2 may flow toward the second ice maker 500.

The cold air passage may further include a third cold air passage P3. The third cold air passage P3 may guide cold air of the second space 124 to an outside of the first refrigerating chamber door 10. Cold air from a lower portion of the second space 124 may flow through the third cold air passage P3.

Meanwhile, the first ice maker 200 may include an ice tray 210 configured to form an ice making cell. The first ice maker 200 may further include a driver that provides power to automatically rotate the ice tray 210 to separate ice from the ice tray 210. The first ice maker 200 may further include a power transmission unit that transmits a power of the driver to the ice tray 210.

The ice tray 210 may include a plurality of ice making cells. Water discharged from a water supply portion and dropped onto the ice tray 210 may be distributed to the plurality of ice making cells. When the ice generation in the ice tray 210 is completed, the ice may be separated from the ice tray 210 as the ice tray 210 is rotated (or twisted) by the driver. An ice separated from the ice tray 210 may be stored in the first ice bin 280. The second ice maker 500 may include the first tray 510.

The second ice maker 500 may include a tray. The tray may include a first tray 510. The tray may further include a second tray 550. The first tray 510 and the second tray 550 may form an ice making cell 501. The second tray 550 may be moved relative to the first tray 510. For example, the second tray 550 may rotate relative to the first tray 510, move linearly relative to the first tray 510, or move linearly and rotate relative to the first tray 510.

If the second tray 550 is a rotation type tray, water supply may be performed at a water supply position of the second tray 550. After the water supply is completed, the second tray 550 may be rotated to an ice making position. If the second tray 550 is a linear movement type tray, water supply may be performed at the ice making position of the second tray 550. If the second tray 550 is a rotation type tray, at least a portion of the second tray 550 may be spaced apart from at least a portion of the first tray 510 at the water supply position. A portion of the second tray 550 spaced apart from the first tray 510 at the water supply position may come into contact with the first tray 510 at the ice making position to form the ice making cell 501.

The dispenser 11 may include a dispenser housing 11a. The dispenser housing 11a may form a receiving space. A container such as a cup may be positioned in the receiving space. Water or ice may be discharged into the receiving space.

An ice chute 700 may be disposed at a lower side of the first space 122. The ice chute 700 may be opened and closed by a cap duct 900. An ice guide 800 may be disposed at a lower side of the ice chute 700. The ice chute 700 may guide ice discharged from the first ice bin 280 to the ice guide 800. The ice guide 800 may guide ice and finally discharge the ice. The ice chute 700 may overlap at least a portion of the first space 122 in a vertical direction. At least a portion of the ice chute 700 may overlap at least a portion of the second space 124 in the vertical direction.

A water tank 340 may be detachably mounted on the first refrigerating chamber door 10. At least a portion of the ice chute 700 may overlap the water tank 340 in a vertical direction.

FIG. 8 is a perspective view of a second ice maker according to a first embodiment. FIG. 9 is a cross-sectional view taken along line 9-9 of FIG. 8.

Referring to FIGS. 8 and 9, the second ice maker 500 may include a first tray assembly and a second tray assembly.

The first tray assembly may include a first tray 510, a first tray case, or the first tray 510 and the first tray case. The second tray assembly may include a second tray 550, a second tray case, or the second tray 550 and the second tray case.

The second ice maker 500 may include a bracket 520. The bracket 520 may be a component of the first tray assembly. The bracket 520 may be a component of the first tray case. The bracket 520 may be installed, for example, on a wall forming the second space 124.

The second ice maker 500 may include an ice making cell 501, which is a space in which water is phase-changed into ice by cold (for example, cold air). In the present embodiment, the first tray 510 and the second tray 550 may be arranged in a vertical direction while forming the ice making cell 501. Of course, it is also possible for the first tray 510 and the second tray 550 to be arranged in a front-back direction or a left-right direction.

A plurality of ice making cells 501 may be defined by the first tray 510 and the second tray 550.

When water is supplied to the ice making cell 501 and the water is cooled by cold air, ice having a shape identical to or similar to the ice making cell 501 may be generated. In the present embodiment, for example, the ice making cell 501 may be formed in a spherical shape or a shape similar to a spherical shape. Of course, the ice making cell 501 may also be formed in a rectangular parallelepiped shape or a polygonal shape.

For example, the first tray case may include the bracket 520. The first tray case may further include a first supporter 530. At least a portion of the first supporter 530 may be positioned at one side of the first tray 510.

The second ice maker 500 may further include a first pusher 540 to separate ice in an ice separation process. The first pusher 540 may receive power from a driver 580 to be described later. The first supporter 530 may support the first tray 510. The first supporter 530 may guide movement of the first pusher 540. The first pusher 540 may be coupled to a pusher link 548. At this time, the first pusher 540 may be rotatably coupled to the pusher link 548. Accordingly, when the pusher link 548 moves, the first pusher 540 may also be guided and moved by the first supporter 530.

The second tray case may include, for example, a second tray cover 560. The second tray case may further include a second supporter 570. For example, at least a portion of the second tray cover 560 may be positioned at one side of the second tray 550. At least a portion of the second supporter 570 may be positioned at another side of the second tray 550.

The second supporter 570 may support the second tray 550 at another side of the second tray 550. An elastic member 547 may be connected to one side of the second supporter 570. The elastic member 547 may provide elastic force to the second supporter 570 so that the second tray 550 may maintain contact with the first tray 510.

The second ice maker 500 may further include a driver 580 that provides driving power. The second tray 550 may move relative to the first tray 510 by receiving a driving power of the driver 580. The first pusher 540 may move by receiving the driving power of the driving force 580. A connecting arm 549 may be coupled to the driver 580. The connecting arm 549 may be connected to the second supporter 570 and may transmit a power of the driver 580 to the second supporter 570.

The driver 580 may include a motor and a plurality of gears. A full ice detection lever may be connected to the driver 580. The full ice detection lever may be rotated by a rotational force provided by the driver 580.

The driver 580 may further include a cam that rotates by receiving a rotational power of the motor. The second ice maker 500 may further include a sensor that detects a rotation of the cam. For example, the cam may be provided with a magnet, and the sensor may be a hall sensor for detecting a magnetism of the magnet during a rotation of the cam. Depending on whether the sensor detects the magnet, the sensor may output different outputs, a first signal and a second signal. A controller described below may identify a position of the second tray 550 (or the second tray assembly) based on a type and pattern of a signal output from the sensor.

The second ice maker 500 may further include a second pusher 590. The second pusher 590 may be installed, for example, on the bracket 520.

The second ice maker 500 may include an ice separation heater 503. The ice separation heater 503 may supply heat to the ice making cell 501 at least in an ice separation process. The ice separation heater 503 may be referred to as a first heater. However, if ice separation may be smoothly performed by the first pusher 540, the ice separation heater 503 may be omitted. The ice separation heater 503 may be installed in the bracket 520, for example. The ice separation heater 503 may be in contact with the first tray 510.

The second ice maker 500 may further include a transparent ice heater 505. The transparent ice heater 505 may supply heat to the ice making cell 501 at least in an ice making process. The transparent ice heater 505 may be in contact with the second tray 550, for example. The transparent ice heater 505 may be referred to as a second heater. The second pusher 590 may push out ice disposed in the ice making cell 501.

FIG. 10 is a control block diagram of a refrigerator according to a first embodiment. FIG. 11 is a flow chart for explaining a process of ice generation in a second ice maker according to a first embodiment. FIG. 12 is a drawing showing a state in which a water supply is completed at a water supply position. FIG. 13 is a drawing showing a state in which a second tray is moved to an ice making position. FIG. 14 is a drawing showing a first parabola, which is an output change line of a transparent ice heater according to a first embodiment.

FIG. 14 shows a graph of an output change of a transparent ice heater to ensure that a temperature at a lowest point in an ice making cell is maintained at a first reference temperature while considering a direction of ice generation.

Referring to FIGS. 10 to 14, a refrigerator of the present embodiment may further include a cold air supply 1020 (or a cooler) to supply cold air. The cold air supply 1020 may supply cold air to the second space 124 using, for example, a refrigerant cycle.

The cold air supply 1020 may include, for example, a compressor for compressing refrigerant. A temperature of cold air supplied to the second space 124 may vary depending on an output (or frequency) of the compressor. Alternatively, the cold air supply 1020 may include a fan for blowing air to an evaporator. An amount of cold air supplied to the second space 124 may vary depending on an output (or rotation speed) of the fan. Alternatively, the cold air supply 1020 may include a refrigerant valve that controls an amount of refrigerant flowing in the refrigerant cycle. An amount of refrigerant flowing in the refrigerant cycle varies by controlling an opening degree of the refrigerant valve, and thereby a temperature of cold air supplied to the second space 124 may vary. In the present embodiment, the cold air supply 1020 may include at least one of the compressor, the fan, or the refrigerant valve.

A refrigerator of the present embodiment may further include a controller 1000 to control the cold air supply 1020.

The refrigerator may further include a flow sensor 1002 for detecting an amount of water supplied through the water supply 546. The refrigerator may further include a water supply valve 1004 to control an amount of water supplied.

The above controller 1000 may control some or all of the ice separation heater 503, the transparent ice heater 505, the driver 580, the cold air supply 1020, and the water supply valve 1004.

The refrigerator may further include an ice making chamber temperature sensor 1005 to detect a temperature of the second space 124. The controller 1000 may include a sensor (tray temperature sensor) 410 mounted on the first tray 510. The controller 1000 may determine whether an ice making is complete based on a temperature detected by the sensor 410.

Hereinafter, a process of ice generation in a second ice maker will be described. As long as a heater control technology in a second ice maker described in this embodiment is applied, structural changes to the second ice maker are possible, and the same heater control technology can be applied even when the structure is changed in various forms.

In order to generate ice in the second ice maker 500, the controller 1000 moves the second tray 550 to a water supply position (S11).

In this specification, a direction of movement from a water supply position of FIG. 12 to an ice making position of FIG. 13 may be referred to as a reverse direction (reverse movement or reverse rotation). A direction of movement from a position of FIG. 13 to a position of FIG. 12 may be referred to as a forward direction (forward movement or forward rotation).

A movement of the second tray 550 t of a water supply position is detected by a not shown sensor, and when it is detected that the second tray 550 is moved to a water supply position, the controller 1000 stops the driver 580.

When the second tray 550 is moved to a water supply position, the controller 1000 may determine whether a temperature detected by the sensor 410 is reached a temperature lower than or equal to a water supply start temperature. If it is determined that a temperature detected by the sensor 410 is reached a temperature lower than or equal to an initial water supply start temperature, the controller 1000 may control the water supply valve 1004 so that a water supply is performed (S2). Alternatively, when the second tray 550 is moved to a water supply position, a water supply may be performed immediately.

When a water supply is completed, the second tray 550 may be moved to an ice making position (S3). An ice making may be started when the second tray 550 is moved to an ice making position (S4). For example, an ice making may be started when the second tray 550 reaches an ice making position. Alternatively, an ice making may be started when the second tray 550 reaches an ice making position and a predetermined time has elapsed after a water supply is completed.

When an ice making is started, the controller 1000 may control the cold air supply 1020 so that cold air is supplied to the ice making cell 501. Of course, it is also possible that an ice making is started when a water supply is completed while cold air is being supplied to the ice making cell 501 by the cold air supply 1020.

The controller 1000 may determine whether a turn-on condition of the transparent ice heater 505 is satisfied (S5). If it is determined that the turn-on condition of the transparent ice heater 505 is satisfied, the controller 1000 may control the transparent ice heater 505 to be turned on during at least a period in which the cold air supply 1020 supplies cold air to the ice making cell 501 (S6).

When the transparent ice heater 505 is turned on, heat of the transparent ice heater 505 is transferred to the ice making cell 501, so that an ice generation in the ice making cell 501 may be delayed. As in the present embodiment, transparent ice may be generated in the second ice maker 500 by delaying an ice generation so that bubbles dissolved in the water within the ice making cell 501 moves from a portion, at which the ice is made, toward water that is in a liquid state by heat of the transparent ice heater 505.

When the transparent ice heater 505 is turned on, heat of the transparent ice heater 505 is transferred into the ice making cell 501. When the second tray 550 is positioned at a lower side of the first tray 510 and the transparent ice heater 505 is disposed to supply heat to the second tray 550, ice may generated from an upper side of the ice making cell 501. In the present embodiment, since ice is generated from one side in the ice making cell 501, air bubbles in a portion of the ice making cell 501 where ice is generated move to another side toward a water in a liquid state. Since a density of water is greater than a density of ice, water or air bubbles maty be convected within the ice making cell 501, and the air bubbles may move toward the transparent ice heater 505.

As ice grows, a ratio of water and ice within the ice making cell 501 changes and a saturation of bubbles increases. Therefore, the controller 1000 may vary a heating amount of the transparent ice heater 505 in an ice making process so that a difference in transparency of ice generated by height is reduced.

In this specification, a variation of the cooling power of the cold air supply 1020 may include at least one of variation of an output of the compressor, variation of an output of a fan, or variation of an opening degree of a refrigerant valve. A variation of a heating amount of the transparent ice heater 505 may mean variation of an output of the transparent ice heater 505 or variation of a duty of the transparent ice heater 505. At this time, a duty of the transparent ice heater 505 may mean a ratio of an on-time to an on-time and off-time of the transparent ice heater 505 in one cycle, or may mean a ratio of an off-time to an on-time and off-time of the transparent ice heater 505 in one cycle.

Hereinafter, an example of varying an output of the transparent ice heater 505 will be described. An increase in an output of the transparent ice heater 505 described below may be interpreted as an increase in a duty of the transparent ice heater 505. A decrease in an output of the transparent ice heater 505 described below may be interpreted as a decrease in a duty of the transparent ice heater 505.

A control of the transparent ice heater 505 for generating transparent ice may be divided into a plurality of processes. In FIG. 14, as an example, the transparent ice heater 505 is controlled in seven processes. Each of the plurality of processes may be performed for a certain time.

An output change graph of the transparent ice heater 505 in FIG. 14 is a graph that connects an output of the transparent ice heater for each process, which is determined to maintain a temperature of a lowermost portion of an ice making cell within a first reference temperature or a reference temperature range including the first reference temperature, considering a volume ratio of ice and water within an ice making cell. An output change graph in FIG. 14 may be referred to as a first parabola (or a first output line or a first heating amount line).

The first reference temperature may be, for example, 4 degrees Celsius. Since a density of water is the highest when it is four degrees Celsius, a flow of water within an ice making cell may be minimized, and thus a spreading of bubbles within water may be minimized. Therefore, a transparency of ice may increase as ice grows from one side to another side.

A lowermost portion within the ice making cell may be a region substantially including a portion where the transparent ice heater 505 makes contact.

In order to generate ice with increased transparency, an output of the transparent ice heater 505 may be controlled to output the first parabola.

In a first process, the transparent ice heater 505 may operate at a first output WH1. The first output WH1 is an initial output of the transparent ice heater 505.

In a second process, the transparent ice heater 505 may operate at a second output WH2. The second output WH2 may be less than the first output WH1.

In a third process, the transparent ice heater 505 may operate at a third output WH3. The third output WH3 may be less than the second output WH2.

A difference between the first output WH1 and the second output WH2 may be greater than a difference between the second output WH2 and the third output WH3. Although not limited, the third output WH3 may be a minimum output.

An output of the transparent ice heater 505 may be gradually reduced from an initial output to a minimum output. At this time, an output decrease slope of the transparent ice heater 505 may be reduced.

In a fourth process, the transparent ice heater 505 may operate at a fourth output WH4. The fourth output WH4 may be greater than the third output WH3.

In a fifth process, the transparent ice heater 505 may operate at a fifth output WH5. The fifth output WH5 may be greater than the fourth output WH4. A difference between the fifth output WH5 and the fourth output WH4 may be greater than a difference between the fourth output WH4 and the third output WH3.

In a sixth process, the transparent ice heater 505 may operate at a sixth output WH6. The sixth output WH6 may be greater than the fifth output WH5. The sixth output WH6 may be greater than the first output WH1. A difference between the sixth output WH6 and the fifth output WH5 may be greater than a difference between the fifth output WH5 and the fourth output WH4.

In a seventh process, the transparent ice heater 505 may operate at a seventh output WH7. The seventh output WH6 may be greater than the sixth output WH5. A difference between the seventh output WH7 and the sixth output WH6 may be greater than a difference between the sixth output WH6 and the fifth output WH5.

An output of the transparent ice heater 505 may be increased stepwise after being reduced to a minimum output. At this time, an output increase slope of the transparent ice heater 505 may be increased.

An output increase slope of the transparent ice heater 505 may be greater than an output decrease slope of the transparent ice heater 505. A number of processes in which an output of the transparent ice heater 505 is increased may be greater than a number of processes in which an output of the transparent ice heater 505 is decreased.

Regarding the first parabola, the first parabola is a line representing an output of the transparent ice heater to maintain a temperature of water at a lowermost portion of the ice making cell at a first reference temperature, which is a temperature above zero.

The first parabola may include an output decrease section and an output increase section. An output change slope in the output increase section may be greater than an output change slope in the output decrease section.

From a perspective of ice transparency, it is possible to operate an output of the transparent ice heater 505 at each process of the ice making process at a greater output than an output on the first parabola. However, in this case, there is a disadvantage of delaying an ice making time and may cause unnecessary power consumption of the transparent ice heater.

Therefore, from a perspective of increasing an ice making rate, the transparent ice heater may be controlled to follow an output change graph of a transparent ice heater of FIG. 15, which will be described later.

FIG. 15 is a drawing showing a second parabola, which is an output change line of a transparent ice heater according to a first embodiment.

FIG. 15 shows a graph of an output change of a transparent ice heater to ensure that an ice making rate in an ice making cell satisfies a reference rate while considering a direction of ice generation.

Referring to FIG. 15, the reference rate may be, for example, 5 mm/hour.

A control of the transparent ice heater 505 for generate transparent ice may be divided into a plurality of processes.

In FIG. 15, the transparent ice heater 505 is controlled in seven processes, for example. Each of the processes may be performed for a certain time.

An output change graph of FIG. 15 is a graph that connects an output of the transparent ice heater for each process determined to maintain an ice making rate within a reference rate or a reference rate range including a reference rate, considering a volume ratio of ice and water in an ice making cell. An output change graph in FIG. 15 may be referred to as a second parabola (or a second output line or a second heating amount line).

When a transparent ice heater is controlled by following the second parabola, an average temperature of water in each unit area where ice is generated in the ice making cell may be maintained within a second reference temperature or a temperature range including a second reference temperature. At this time, the second reference temperature may be zero degrees.

An average temperature of water in each unit area must be maintained at zero degrees or a temperature above zero so that ice may be sequentially generated from one side (or upper side) to another side (or lower side) of an ice making cell.

In order to increase an ice making rate, an output of the transparent ice heater 505 may be controlled to follow the second parabola.

In a first process, the transparent ice heater 505 may operate at a first output WL1. The first output WL1 is an initial output of the transparent ice heater 505.

In a second process, the transparent ice heater 505 may operate at a second output WL2. The second output WL2 may be less than the first output WL1.

In a third process, the transparent ice heater 505 may operate at a third output WL3. The third output WL3 may be less than the second output WL2. A difference between the first output WL1 and the second output WL2 may be greater than a difference between the second output WL2 and the third output WL3.

In a fourth process, the transparent ice heater 505 may operate at a fourth output WL4. The fourth output WL4 may be less than the third output WL3. A difference between the second output WL2 and the third output WL3 may be greater than a difference between the third output WL3 and the fourth output WL4.

In a fifth process, the transparent ice heater 505 may operate at a fifth output WL5. The fifth output WL5 may be less than the fourth output WL4. A difference between the third output WL3 and the fourth output WH4 may be greater than a difference between the fourth output WH4 and the fifth output WH5.

In a sixth process, the transparent ice heater 505 may operate at a sixth output WL6. The sixth output WL6 may be less than the fifth output WL5. A difference between the fourth output WL4 and the fifth output WL5 may be equal to or greater than a difference between the fifth output WL5 and the sixth output WL6.

In a seventh process, the transparent ice heater 50F may operate at a seventh output WL7. The seventh output WL7 may be less than the sixth output WL6. A difference between the fifth output WL5 and the sixth output WL6 may be greater than a difference between the sixth output WL6 and the seventh output WL7.

An output of the transparent ice heater 505 may be decreased stepwise from an initial output. Therefore, the first output WL1 may be a maximum output. At this time, an output decrease slope of the transparent ice heater 505 may be decreased. Or, an output decrease slope of the transparent ice heater 505 may be decreased or maintained and then decreased again.

Regarding the second parabola, the second parabola is a line representing an output of a transparent ice heater so that a temperature of water per unit area in an ice making cell is maintained at a second reference temperature.

The second parabola may include an output decrease section. An output change slope may be decreased stepwise in the output decrease section. Alternatively, an output change slope may decrease and then remain constant and then decrease again in the output decrease section.

In terms of ice making rate, it is possible to operate an output of the transparent ice heater 505 at each process of the ice making process with an output less than an output on the second parabola. However, in this case, there is a disadvantage that a transparency is reduced.

Therefore, it is possible to consider controlling a transparent ice heater so that a transparency can be improved while an ice making rate is increased.

For example, an output of the transparent ice heater 505 may be determined as an output of a region between the first parabola and the second parabola. That is, the transparent ice heater 505 may be controlled to follow a final output line (or a final heating amount line) between the first parabola and the second parabola.

In summary, the controller 1000 may control the transparent ice heater 505 to be turned on during at least a period in which the cold air supply supplies cooling power so that a transparency of a solid state object generated in the ice making cell may be improved.

The controller 1000 may control an output of the transparent ice heater 505 to be adjusted within a preset output range so as to maintain an ice making rate of a liquid state object within the ice making cell within a preset range that is less than an ice making rate when an ice making is performed in a state in which a transparent ice heater is turned off. The preset output range may be provided between the preset first parabola and the preset second parabola.

FIG. 16 is a drawing showing a final output line of a transparent ice heater determined between a first parabola and a second parabola for controlling a transparent ice heater.

In FIG. 16, a final output line may mean a line connecting a final output of the transparent ice heater determined between the first parabola and the second parabola.

A relationship between the first parabola and the second parabola is described.

A difference between an output at each process on the first parabola and an output at each process on the second parabola may increase as an ice making process progresses.

An output on the first parabola may decrease from an initial output and then increase. An output on the second parabola may decrease from an initial output. An output on the first parabola is greater than an output on the second parabola.

An output on the first parabola may be an upper limit output of the transparent ice heater 505. An output on the second parabola may be a lower limit output of the transparent ice heater 505. An upper limit output and an lower limit output may mean a limit output of the transparent ice heater 505 that may operate to generate ice with increased transparency.

The first parabola may be a result considering a first factor. The second parabola may be a result considering a second factor.

In one aspect, the first factor may be a transparency of ice, and the second factor may be an ice making rate. In another aspect, the first factor may be a first ice making rate, and a second factor may be a second ice making rate. The second ice making rate may be faster than the first ice making rate. In another aspect, the first factor is a first transparency, and the second factor is a second transparency. The first transparency may be greater than the second transparency.

A temperature of water in an ice making cell 501 when the transparent ice heater 505 operates at an output on the first parabola may be higher than a temperature of water in an ice making cell 501 when the transparent ice heater 505 operates at an output on the second parabola.

The first parabola may include a decrease section in which an output decreases and an increase section in which an output increases. An absolute value of an output increase slope in the increase section may be greater than an absolute value of an output decrease slope in the decrease section.

The second parabola may include a section in which an output decrease slope decreases. The second parabola may include a section in which an output reduction slope is maintained constant.

An output at each process on a final output line may be determined by a sum of an output on the first parabola x weighting value a and an output on the second parabola x weighting value b.

A sum of the weighting value a and the weighting value b is 1.

The weighting value a and the weighting value b for each process may be variable. At this time, the weighting value a may be a volume or mass ratio of water in a total volume or mass of an ice making cell. Or, the weighting value a may be a predetermined value. The weighting value b may be a volume or mass ratio of ice in a total volume or mass of an ice making cell. Or, the weighting value b may be a predetermined value.

A control of the transparent ice heater 505 for generating ice considering transparency and ice making rate may be divided into a plurality of processes.

In FIG. 16, as an example, the transparent ice heater 505 is controlled in seven processes. Each of the processes may be performed for a certain time. That is, when one process is performed for a certain time, the next process may be performed.

An output of the transparent ice heater 505 may be controlled to follow the final output line.

In a first process, the transparent ice heater 505 may operate at a first output WF1. The first output WF1 is an initial output of the transparent ice heater 505. In the first process, the weighting value a may be greater than the weighting value b.

In an initial process of an ice making, since the water ratio is a hundred percent, the first output WF1 in the first process may be equal to a first output WH1 on the first parabola. Of course, the first output WF1 may be less than a first output WH1 on the first parabola.

In a second process, the transparent ice heater 505 may operate at a second output WF2. The second output WF2 may be less than the first output WF1. In the second process, the weighting value a may be greater than the weighting value b.

In a third process, the transparent ice heater 505 may operate at a third output WF3. The third output WF3 may be less than the second output WF2. A difference value between the first output WF1 and the second output WF2 may be equal to or different from a difference value between the second output WF2 and the third output WF3. In a third process, the weighting value a may be greater than the weighting value b.

In a fourth process, the transparent ice heater 505 may operate at a fourth output WF4. The fourth output WF4 may be less than the third output WF3. In the fourth process, the weighting value a may be greater than the weighting value b.

A difference between the third output WF3 and the fourth output WF4 may be greater than a difference between the second output WF2 and the third output WF3.

In a fifth process, the transparent ice heater 505 may operate at a fifth output WF5. The fifth output WF5 may be less than the fourth output WF4. In the fifth process, the weighting value b may be equal to or greater than the weighting value a.

A difference between the third output WF3 and the fourth output WF4 may be greater than a difference between the fourth output WF4 and the fifth output WF5.

In a sixth process, the transparent ice heater 505 may operate at a sixth output WF6. The sixth output WF6 may be less than the fifth output WF5. In the sixth process, the weighting value b may be greater than the weighting value a. A difference between the fifth output WF5 and the sixth output WF6 may be greater than a difference between the fourth output WF4 and the fifth output WF5.

In a seventh process, the transparent ice heater 505 may operate at a seventh output WF7. The seventh output WF7 may be less than the sixth output WF6. A difference between the fifth output WF5 and the sixth output WF6 may be greater than a difference between the sixth output WF6 and the seventh output WF7.

An output of the transparent ice heater 505 may be decreased stepwise from an initial output. Therefore, the first output WF1 may be a maximum output.

At this time, an output decrease slope of the transparent ice heater 505 may be variable.

Alternatively, a final output line of the transparent ice heater 505 may include a section in which an output decrease slope is maintained constant. The final output line may include a section in which the output reduction slope increases. The final output line may include a section in which the output reduction slope decreases.

To summarize the final output line above, the final output line is a line representing an output of a transparent ice heater that increases transparency while also increasing an ice making rate.

When an ice making process is divided into the a first ice making section and a second ice making section, the final output line may be positioned close to the first parabola in the first ice making section. In the second ice making section, the final output line may be positioned close to the second parabola.

In the first ice making section, the weighting value a may be greater than the weighting value b. In the second ice making section, the weighting value b may be greater than the weighting value a.

An initial output on the final output line may be close to the first parabola. A final output on the final output line may be close to the second parabola.

The final output line may be determined from a viewpoint of increasing transparency in the first ice making section. The final output line may be determined from a viewpoint of increasing an ice making rate in the second ice making section.

Therefore, since an ice making time may be shortened in the entire ice making section, there is an advantage in that a daily ice making amount may be increased.

If an output of the transparent ice heater is decreased in the second ice making section, there is an advantage in that a power consumption due to an operation of the transparent ice heater may be reduced.

When a seventh process is completed or during an execution of any one of first to seventh processes, if a ratio of a volume (or mass) of a residual water to a total volume (or mass) of the ice making cell becomes less than or equal to a reference value, a current process is ended and an eighth process may be additionally performed.

The reference value may be determined based on a volume (or mass) of a residual water from a lowermost portion of the ice making cell to a portion where the transparent ice heater 505.

When the eighth process is performed after the seventh process is completed, an output of the transparent ice heater 505 in the eighth process may be equal to or less than an output of the transparent ice heater 505 in the seventh eighth process. Alternatively, the transparent ice heater 505 may be turned off in the eighth process. Alternatively, the transparent ice heater 505 may be turned off when the seventh process is completed.

The eighth process may be completed when a temperature detected by the tray temperature sensor 410 reaches an ice making completion reference temperature. In other words, the eighth process may be referred to as an ice making completion determination process.

The controller 1000 may turn off the transparent ice heater 505 if it is determined that an ice making is complete (S9). For example, if the controller 1000 determines that a temperature detected by the tray temperature sensor 410 is reached the ice making completion reference temperature, it may determine that an ice making is completed and the controller 1000 may turn off the transparent ice heater 505.

Alternatively, if the transparent ice heater 505 is turned off in the process, step S9 may be omitted. At this time, the controller 1000 may determine that an ice making is completed if it is determined that a temperature detected by the tray temperature sensor 410 is reached the ice making completion reference temperature.

When an ice making is completed, the controller 1000 operates at least one of the ice separation heater 503 or the transparent ice heater 505 for ice separation S10.

When at least one of the ice separation heater 503 or the transparent ice heater 505 is turned on, heat of the heater is transferred to at least one of the first tray 510 or the second tray 550, so that ice may be separated from a surface (an inner surface) of at least one of the first tray 510 or the second tray 550. Heat of the heaters 503 and 505 is transferred to contact surfaces of the first tray 510 and the second tray 550, so that contacts surface of the first tray 510 and the second tray 550 becomes separable.

The controller 1000 operates the driver 580 to move the second tray 550 to an ice separation position (to move in a forward direction) when an operation start condition of the driver 580 is satisfied (S11).

When the second tray 550 moves in a forward direction, the second tray 550 is separated from the first tray 510. A moving force of the second tray 550 is transmitted to the first pusher 540. Then, the first pusher 540 is lowered, so that a pushing column 544 passes through an opening 514 to press the ice in the ice making cell 501.

During a process of the second tray 550 moving to an ice separation position, the second tray 550 may be in contact with the pushing column 592. As the second tray 550 continues to move to an ice separation position, the pushing column 592 presses the second tray 550, causing the second tray 550 to deform, and a pressing force of the pushing column 592 may be transmitted to ice, allowing the ice to separate from a surface of the second tray 550.

The controller 1000 may determine whether an operation end condition of a heater is satisfied. For example, the controller 1000 may determine that an operation end condition of a heater is satisfied when an operation time of the driver 580 reaches a reference time or a temperature detected by the sensor 410 is equal to or higher than an end reference temperature. When an operation end condition of the heater is satisfied, the controller 1000 may turn off a turned-on heater. Although not limited, the end reference temperature may be set to a temperature above zero.

After ice is separated from the second tray 550, the controller 1000 controls the driver 480 so that the second tray 550 moves in a reverse direction. Then, the second tray 550 moves from an ice separation position toward a water supply position. When the second tray 550 moves to a water supply position of FIG. 12, the controller 1000 stops the driver 580.

As another example, in the present embodiment, the controller may be provided to select one of a plurality of ice making modes. In one of the plurality of ice making modes, an output of the heater may be controlled to a value closer to the first output line. In another of the plurality of ice making modes, an output of the heater may be controlled to a value closer to the second output line.

One of the plurality of ice making modes may be defined as a first mode having a higher transparency than another of the plurality of ice making modes. Another of the plurality of ice making modes may be defined as a second mode having a lower transparency.

One of the plurality of ice making modes may be defined as mode A, which has a slower ice making rate than another of the plurality of ice making modes, and another of the plurality of ice making modes may be defined as mode B.

FIG. 17 is a drawing showing an output line of a transparent ice heater according to a second embodiment.

This embodiment is identical to a first embodiment in other parts, but has a difference in an output control of the transparent ice heater. Therefore, only characteristic parts of this embodiment will be described below.

Referring to FIG. 17, a transparent ice heater 505 may be controlled in a plurality of processes in an ice making process.

In this embodiment, an output line of a heater may be a simplified output line of a final output line of FIG. 16. According to an output line of this embodiment, a number of output variations of the transparent ice heater may be reduced compared to a first embodiment, so there is an advantage of simplified control.

For example, a plurality processes may include a first process, a second process, and a third process.

In the first process, the transparent ice heater 505 may operate at a first output W11. The first process may be performed for a first reference time.

In the second process, the transparent ice heater 505 may operate at a second output W12. The second process may be performed for a second reference time. The second reference time may be equal to or different from the first reference time. The second output W12 may be less than the first output W11.

In the third process, the transparent ice heater 505 may operate at a third output W13. The third process may be performed for a third reference time. The third reference time may be greater than the first reference time and the second reference time.

The third output W13 may be less than the second output W12. A difference between the second output W12 and the third output W13 may be greater than a difference between the first output W11 and the second output W12. The third output W13 may be more than 1/2 of the first output W11.

As another example, an output of the transparent ice heater 505 in the first process may be variable. A representative output of the transparent ice heater 505 in the first process may be the first output W11.

An output of the transparent ice heater 505 in the second process may be variable. A representative output of the transparent ice heater 505 in the second process may be the second output W12. The second output W12 may be less than the first output W11.

In the third process, an output of the transparent ice heater 505 may be variable. In the third process, a representative output of the transparent ice heater 505 may be the third output W13. The third output W13 may be less than the second output W12.

A representative output may be an average output at each process, a maximum or minimum value of an output at each process, a value between a maximum value and a minimum of the output at each process, an average value (medium value) of a maximum value and a minimum value of the output at each process, or an initial value or a final value of an output at each process.

In the present embodiment, as an ice making process progresses, an output of the transparent ice heater 505 may be gradually reduced. An output decrease slope of the transparent ice heater 505 may be increased.

According to this embodiment, a transparency may be increased in an initial ice making section, and an ice making rate may be increased in a final ice making section.

FIG. 18 is a drawing showing an output line of a transparent ice heater according to a third embodiment.

This embodiment is identical to a first embodiment in other parts, but has a difference in a form of a final output line described in FIG. 16. Therefore, only characteristic parts of this embodiment will be described below.

Referring to FIG. 18, a control of the transparent ice heater 505 in the ice making process may be divided into a plurality of processes.

In a first process, the transparent ice heater 505 may be operated at a first output W21. The first process may be ended when a volume (or mass) ratio of ice to a total volume (or mass) of the ice making cell reaches a reference value.

When a first process is ended, a second process may be performed. In the second process, an output of the transparent ice heater 505 may be controlled to follow a final output line disposed between the first parabola and the second parabola.

After the second process, an output at each process on the final output line may be determined by a sum of an output on the first parabola x weighting value a and an output on the second parabola x weighting value b.

A sum of the weighting value a and the weighting value b is 1. The weighting value a and the weighting value b for each process may be variable. At this time, the weighting value a and the weighting value b for each process may be predetermined values.

In the second process, the transparent ice heater 505 may operate at a second output W22. The second output W22 may be greater than the first output W21. The first output W21 may be an average value of an output of the first parabola in the second process and an output of the second parabola in the second process.

In the second process, the weighting value a may be greater than the weighting value b. Although not limited, the weighting value a may be 1 in the second process.

In this case, a time for which the first process is performed may be greater than a time for which the second process is performed.

In a third process, the transparent ice heater 505 may operate at a third output W23. The third output W23 may be less than the second output W22. The third output W23 may be greater than the first output W21. In the third process, the weighting value a may be greater than the weighting value b.

In a fourth process, the transparent ice heater 505 may operate at a fourth output W24. The fourth output W24 may be less than the third output W23. The fourth output W24 may be greater than the first output W21. A difference between the third output W23 and the fourth output W24 may be greater than a difference between the second output W22 and the second output W22. In the fourth process, the weighting value a may be equal to or similar to the weighting value b.

In a fifth process, the transparent ice heater 505 may operate at a fifth output W25. The fifth output W25 may be less than the fourth output W24. The fifth output W25 may be less than the first output W21. That is, a final output of the transparent ice heater 505 may be less than an initial output.

A difference between the fourth output W24 and the fifth output W25 may be equal to or different from a difference between the third output W23 and the fourth output W24. In the fifth process, the weighting value b may be greater than the weighting value a.

In the present embodiment, an output line of the transparent ice heater 506 may include a section in which an output increases. An output line of the transparent ice heater 506 may include a section in which an output is maintained. An output line of the transparent ice heater 506 may include a section in which an output decreases.

A section in which the output is decreased may include a section in which an output decrease slope remains constant. A section in which the output is decreased may include a section in which an output decrease slope increases.

FIG. 19 is a drawing showing a change in output of a transparent ice heater in an ice making process according to a fourth embodiment.

A structure of a refrigerator in this embodiment is identical to previous embodiments, but there is a difference in a control of the transparent ice heater. Therefore, only characteristic parts of this embodiment will be described below.

FIG. 19 illustrates, for example, that a transparent ice heater 505 is controlled by dividing an ice making process into an initial section (first ice making section), a middle section (second ice making section), and a final section (third ice making section).

Referring to FIG. 19, in the present embodiment, the transparent ice heater 505 may operate at a first heating amount in an initial section. For example, the transparent ice heater 505 may operate at a first output W31 in an initial section.

In the initial section, an output of the transparent ice heater 505 may be maintained constant. The initial section may be performed for a first reference time.

After the transparent ice heater 505 operates in the initial section, an output of the transparent ice heater 505 may be variably controlled in the middle section. The middle section may be performed for a second reference time. The second reference time may be greater than the first reference time.

In the middle section, the transparent ice heater 505 may be operated at a second heating amount. For example, the second heating amount of the transparent ice heater 505 may be variably controlled in the middle section.

The middle section may be divided into a plurality of processes. An output of the transparent ice heater 505 may be controlled for each of the processes. Each process may be performed for a predetermined set time. However, there is no limitation on a number of processes performed in the middle section.

In a first process of the middle section, the transparent ice heater 505 may operate at a second output W32. The second output W32 may be an initial output in the middle section. The second output W32 may be less than the first output W31.

In the present embodiment, in order to generate ice from an upper side of an ice making cell 501, an output of the transparent ice heater 505 in the initial section is greater than an output of the transparent ice heater 505 in the middle section.

In a second process of the middle section, the transparent ice heater 505 may operate at a third output W33. The third output W33 may be less than the second output W32. A difference between the first output W31 and the second output W32 may be greater than the difference between the second output W32 and the third output W33.

In a third process of the middle section, the transparent ice heater 505 may operate at a fourth output W34. The fourth output W34 may be less than the third output W33.

A difference between the second output W32 and the third output W33 may be greater than a difference between the third output W33 and the fourth output W34. Although not limited, an output of the transparent ice heater 505 may be decreased to a minimum output in the middle section. An output of the transparent ice heater 505 may be decreased stepwise in at least a section of the middle section.

An output of the transparent ice heater 505 may be determined to be decreased stepwise in at least a section of the middle section by reflecting an amount of water per unit height in the ice making cell 501 and a distance between a portion where ice is to be generated and the transparent ice heater 505.

In the initial section and at least a section of the middle section, an output decrease slope of the transparent ice heater 505 may be decreased.

In a fourth process of the middle section, the transparent ice heater 505 may operate at a fifth output W35. The fifth output W35 may be greater than the fourth output W34. That is, after the transparent ice heater 505 operates at a minimum output in the middle section, an output of the transparent ice heater 505 may be increased.

In a fifth process of the middle section, the transparent ice heater 505 may operate at a sixth output W36. The sixth output W36 may be greater than the fifth output W35. The sixth output W36 may be greater than the second output W32. That is, in the middle section, a final output may be greater than an initial output.

In another section of the middle section, an output of the transparent ice heater 505 may be increased stepwise.

A difference between the sixth output W36 and the fifth output W35 may be greater than a difference between the fifth output W35 and the fourth output W34.

In another section of the middle section, an output increase slope of the transparent ice heater 505 may be increased.

An output of the transparent ice heater 505 may be determined to increase stepwise in another section of the middle section by reflecting a distance between a portion where ice is to be generated and the transparent ice heater in the ice making cell 501, and a saturation of bubbles within the ice making cell.

As a saturation of bubbles increases, an ice making rate must be slowed down to increase a transparency of the generated ice.

An average value (an average output) of an output of the transparent ice heater 505 in the middle section, may be less than the first output W31 in the initial section.

After the transparent ice heater 505 operates in the middle section, an output of the transparent ice heater 505 may be controlled in the final section.

In summary, the middle section may include a decrease section in which an output of the transparent ice heater 505 decreases, and an increase section in which an output of the transparent ice heater 505 increases.

In the decrease section, a heating amount decrease slope of the transparent ice heater 505 may decrease. In the increase section, a heating amount increase slope of the transparent ice heater 505 may increase.

The final section may be performed for a third reference time.

The third reference time may be greater than the first reference time. The third reference time may be equal to or less than the second reference time. A difference between the second reference time and the first reference time may be greater than a difference between the second reference time and the third reference time.

In the final section, the transparent ice heater 505 may operate at a third heating amount. A heating amount of the transparent ice heater 505 in the final section may be variable or maintained at a constant heating amount.

The final section may be divided into a plurality of processes. For example, an output of the transparent ice heater 505 may be controlled for each of the processes. Each process may be performed for a predetermined set time. However, there is no limitation on a number of processes performed in the final section.

First, as an example, an explanation will be given of an increase in an output of the transparent ice heater (505) in the final section (first control case).

In a first process of the final section, the transparent ice heater 505 may operate at a seventh output W37. The seventh output W37 may be greater than the sixth output W36. The seventh output W37 may be less than the first output W31.

In a second process of the final section, the transparent ice heater 505 may operate at an eighth output W38. The eighth output W38 may be greater than the seventh output W37.

In a third process of the final section, the transparent ice heater 505 may operate at a ninth output W39. The ninth output W39 may be greater than the eighth output W38.

A difference between the ninth output W39 and the eighth output W38 may be less than a difference between the eighth output W38 and the seventh output W37.

In a fourth process of the final section, the transparent ice heater 505 may operate at a tenth output W40. The tenth output W40 may be a final output of the final section. For example, the final output of the final section may be a maximum output in the final section.

The tenth output W40 may be greater than the ninth output W39. The tenth output W40 may be less than the first output W31 of the initial section. A difference between the tenth output W40 and the ninth output W39 may be less than a difference between the ninth output W39 and the eighth output W87.

In the final section, an output of the transparent ice heater 505 may be increased stepwise.

An output of the transparent ice heater 505 may be determined to be increased stepwise in the final section by reflecting a distance between a portion where ice is to be generated in the ice making cell 501 and the transparent ice heater 505, and a saturation of bubbles in the ice making cell.

In the final section, an average value (average output) of an output of the transparent ice heater 505 may be less than the first output W31 in the initial section. In the final section, an average value (average output) of an output of the transparent ice heater 505 may be greater than an average value (average output) of an output of the transparent ice heater 505 in the middle section.

In the final section, an increase slope of an output of the transparent ice heater 505 may be decreased.

As an ice making progresses, an amount of water in the ice making cell decreases, so the resistance for heat transfer of the transparent ice heater 505 decreases and resistance for cold transfer of cold air increases, so that it is possible to increase or maintain transparency even if an increase slope of an output of the transparent ice heater 505 is decreased.

As another example, it will be explained that an output of the transparent ice heater 505 is maintained in the final section (second control case).

Even in this case, an initial output W37 of the transparent ice heater 505 in the final section may be greater than a final output W36 of the transparent ice heater 505 in the middle section. An initial output W37 of the transparent ice heater 505 in the final section may be less than a first output W31 in the initial section. In the final section, an output of the transparent ice heater 505 may be greater than an average value (average output) of an output of the transparent ice heater 505 in the middle section. In the final section, when an output of the transparent ice heater 505 is increased stepwise, average value (average output) of an output the transparent ice heater 505 may be equal to or different from an output of the transparent ice heater 505 when an output of the transparent ice heater 505 is maintained in the final section.

As another example, an output of the transparent ice heater 505 is decreased in the final section (third control case).

In this case, an initial output W37 of the transparent ice heater 505 in the final section may be greater than a final output W36 of the transparent ice heater 505 in the middle section. An output of the transparent ice heater 505 may be decreased stepwise.

Based on the final section, an initial output of the transparent ice heater 505 in the third control case may be greater than an initial output of the transparent ice heater 505 in the first or second control case.

In the final section, an average value (average output) of an output of the transparent ice heater 505 may be greater than an average value (average output) of an output of the transparent ice heater 505 in the middle section.

In the third control case, a final output of the final section may be greater than a final output W36 of the middle section.

According to the heater control method of this embodiment, there is an advantage in that a deviation in a transparency of ice generated by varying an output of the transparent ice heater in an ice making process may be decreased.

In addition, since an output (or average output) of the transparent ice heater in the final section is less than an output of the transparent ice heater in the initial section, there is an advantage in that a transparency may be improved in the final section while an output of the transparent ice heater may be decreased, thereby lowering a power consumption of the transparent ice heater.

Meanwhile, a modified example of the control method described in FIG. 19 will be described.

In a case of the first modified embodiment, an output of a transparent ice heater 505 may be variably controlled by dividing an ice making process into an initial section, a middle section, and a final section.

However, an output of the transparent ice heater 505 may be gradually decreased in an entire of the middle section. An output of the transparent ice heater 505 may be maintained constant in the final section. At this time, an output of the transparent ice heater 505 in the final section may be equal to or less than a final output of the middle section.

According to the first modified embodiment, an output of the transparent ice heater 505 in the final section may be a minimum output. Since a saturation of bubbles in the ice making cell in the final section is greater than in other sections, if an output of the transparent ice heater 505 is maintained at a minimum output, an ice making rate is decreased, but a transparency may be improved or maintained, and a power consumption of a transparent ice heater may be decreased.

In addition, as an ice making progresses, an amount of water in the ice making cell decreases, so resistance for heat transfer of the transparent ice heater 505 decreases and resistance for cold transfer of the cold air increases, so that it is possible to increase or maintain a transparency even if an output of the transparent ice heater 505 is maintained in the final section.

In a case of the second modified embodiment, an output of the transparent ice heater 505 may be variably controlled by dividing an ice making process into an initial section, a middle section, and a final section.

However, an output of the transparent ice heater 505 may be decreased stepwise throughout an entire of the middle section. Additionally, an output of the transparent ice heater 505 may be decreased stepwise in at least a portion of the final section. At this time, an output decrease slope of the transparent ice heater 505 in the final section may be less than an output decrease slope of the transparent ice heater 505 in the middle section.

According to the second modified embodiment, a final output of the transparent ice heater 505 in the terminal section may be a minimum output. Since a saturation of bubbles in the ice making cell in the final section is greater than in other sections, if an output of the transparent ice heater 505 is decreased stepwise, an ice making rate is decreased, but a transparency may be improved or maintained, and a power consumption of the transparent ice heater may be decreased.

In addition, as an ice making progresses, an amount of water in the ice making cell decreases, so resistance for heat transfer of the transparent ice heater 505 decreases and resistance for cold transfer of cold air increases, so that it is possible to increase or maintain transparency even if an output of the transparent ice heater 505 is gradually reduced in the final section.

FIG. 20 is a drawing showing a change in output of a transparent ice heater in an ice making process according to a fifth embodiment.

This embodiment is identical to previous embodiments in other parts, and has a difference in a control of a transparent ice heater. Therefore, only characteristic parts of this embodiment will be described below.

Referring to FIG. 20, it is illustrated that a transparent ice heater 505 is controlled by dividing an ice making process into an initial section, a middle section, and a final section.

In an initial section, the transparent ice heater 505 may operate at a first output W41. An output of the transparent ice heater 505 may be maintained constant in the initial section. The initial section may be performed for a first reference time.

In the initial section, after the transparent ice heater 505 operates, an output of the transparent ice heater 505 may be variably controlled in the middle section.

The middle may be performed for a second reference time. The second reference time may be greater than the first reference time. An output of the transparent ice heater 505 in the middle section may be variably controlled.

The middle section may be divided into a plurality of processes. An output of the transparent ice heater 505 may be controlled for each of the plurality of processes. Each process may be performed for a predetermined set time. However, there is no limitation on a number of processes performed in the middle section.

In a first process of the middle section, the transparent ice heater 505 may operate at a second output W42. The second output W42 may be an initial output in the middle section. The second output W42 may be less than the first output W41.

In the present embodiment, in order to generate ice from an upper side of the ice making cell 501, an output of the transparent ice heater 505 in the initial section is greater than an output of the transparent ice heater 505 in the middle section.

In a second process of the middle section, the transparent ice heater 505 may operate at a third output W43. The third output W43 may be less than the second output W42. A difference between the first output W41 and the second output W42 may be greater than a difference between the second output W42 and the third output W43.

In a third process of the middle section, the transparent ice heater 505 may operate at a fourth output W44. The fourth output W44 may be less than the third output W43. A difference between the second output W42 and the third output W43 may be greater than a difference between the third output W43 and the fourth output W44.

Although not limited, an output of the transparent ice heater 505 may be decreased to a minimum output in the middle section. In at least a section of the middle section, an output of the transparent ice heater 505 may be decreased stepwise. An output of the transparent ice heater 505 may be determined to be gradually decreased in at least section of the middle section by reflecting an amount of water per unit height in the ice making cell 501 and a distance between a portion where ice is to be generated and the transparent ice heater 505.

In the initial section and at least a section of the middle section, an output decrease slope of the transparent ice heater 505 may be decrease.

In a fourth process of the middle section, the transparent ice heater 505 may operate at a fifth output W45. The fifth output W45 may be greater than the fourth output W44. That is, after the transparent ice heater 505 operates at a minimum output in the middle section, an output of the transparent ice heater 505 may be increased.

In a fifth process of the middle section, the transparent ice heater 505 may operate at a sixth output W46. The sixth output W46 may be greater than the fifth output W45. The sixth output W46 may be greater than the second output W42. That is, a final output in the middle section may be greater than an initial output. In another section of the middle section, an output of the transparent ice heater 505 may be increased stepwise.

A difference between the sixth output W46 and the fifth output W45 may be greater than a difference between the fifth output W45 and the fourth output W44. In another section of the middle section, an output increase slope of the transparent ice heater 505 may be increased.

An output of the transparent ice heater (505) may be determined to increase stepwise in another section of the middle section by reflecting a volume (or mass) of ice per unit height in the ice making cell 501 and a saturation of bubbles within the ice making cell.

As a saturation of bubbles increases, an ice making rate may be slowed down to increase a transparency of ice generated. An average value (average output) of an output of the transparent ice heater 505 in the middle section may be less than a first output W41 in an initial section.

In summary, the middle section may include a decrease section in which an output of the transparent ice heater 505 decreases and an increase section in which an output of the transparent ice heater 505 increases.

In the decrease section, a decrease slope of a heating amount of the transparent ice heater 505 may be decreased.

In the increase section, an increase slope of a heating amount of the transparent ice heater 505 may be increased. After the transparent ice heater 505 operates in the middle section, an output of the transparent ice heater 505 may be variably controlled in the final section. The final section may be performed for a third reference time. The third reference time may be greater than the first reference time. The third reference time may be equal to or less than the second reference time. A difference between the second reference time and the first reference time may be greater than a difference between the second reference time and the third reference time.

In the final section, an output of the transparent ice heater 505 may be varied.

The final section may be divided into a plurality of processes. An output of the transparent ice heater 505 may be controlled for each of the processes. Each process may be performed for a predetermined set time. However, there is no limitation on a number of processes performed in the final section.

In a first process of the final section, the transparent ice heater 505 may operate at a seventh output W47. The seventh output W47 may be greater than the sixth output W46. The seventh output W47 may be greater than the first output W41.

In a second process of the final section, the transparent ice heater 505 may operate at an eighth output W48. The eighth output W48 may be greater than the seventh output W47.

In a third process of the final section, the transparent ice heater 505 may operate at a ninth output W49. The ninth output W49 may be equal to or greater than the eighth output W48. A difference between the ninth output W49 and the eighth output W48 may be less than a difference between the eighth output W48 and the seventh output W47.

In a fourth process of the final section, the transparent ice heater 505 may operate at a tenth output W50. The tenth output W50 may be a final output of the final section. The tenth output W50 may be equal to or greater than the ninth output W49.

In the final section, an output of the transparent ice heater 505 may be increased stepwise, or an output may be maintained constant after an output is increased in some section. Or, an output of the transparent ice heater 505 may be decreased stepwise. However, when an output of the transparent ice heater 505 is decreased stepwise, a final output may be greater than the first output W41.

Reflecting a saturation of bubbles in the ice making cell, an output of the transparent ice heater 505 in the final section may be determined to be greater than an output of the transparent ice heater 505 in the initial section.

An average value (average output) of an output of the transparent ice heater 505 in the final section may be greater than a first output W41 in the initial section. The average value (average output) of an output of the transparent ice heater 505 in the final section may be greater than an average value (average output) of an output of the transparent ice heater 505 in the middle section.

In an entire of an ice making process, after an output of the transparent ice heater 505 is decreased to a minimum output, an output of the transparent ice heater 505 may be increased. At this time, an output increase slope of the transparent ice heater 505 may be increased until an output of the transparent ice heater 505 is greater than an output of the initial section. At this time, after an output of the transparent ice heater 505 is greater than an output of the initial section, an output increase slope of the transparent ice heater 505 may be decreased or constant in order to reduce a delay in an ice making.

According to the present embodiment, although an ice making rate may be decreased, there is an advantage in that a transparency of ice generated in the final section may be improved or maintained.

FIG. 21 is a drawing showing a step-by-step output of a transparent ice heater in an ice making process according to a sixth embodiment.

This embodiment is identical to previous embodiments in other parts, and has a difference in a control of a transparent ice heater. Therefore, only characteristic parts of this embodiment will be described below.

Referring to FIG. 21, a control method of a transparent ice heater 505 for generating transparent ice may be divided into a number of processes.

In FIG. 21, as an example, a control method of the transparent ice heater 505 is described as including first to fifth processes. However, it should be noted that there is no limitation on the number of processes to be divided.

An output W of each transparent ice heater 505 of each of the processes may be grouped according to a temperature of the second space 124. Hereinafter, a temperature of the second space 124 is referred to as a temperature of the ice making chamber.

An output of the transparent ice heater 505 may be determined in advance according to a temperature of the ice making chamber. A determined output may be stored in a memory.

In addition, according to a temperature of the ice making chamber for each process, an output of the transparent ice heater 505 may be selected within the same output group or selected from a different output group.

In addition, an output of the transparent ice heater 505 may be maintained or varied depending on a temperature of the ice making chamber while a specific process is being performed.

Each of the first to fifth processes may be performed for a predetermined time t1 to t5. For example, when the first process is started and a first reference time t1 has elapsed, the second process may be performed.

In the first process, an initial output of the transparent ice heater 505 may be a predetermined output. For example, an initial output of the transparent ice heater 505 may be predetermined as an output when a temperature of the ice making chamber is −10 degrees Celsius.

Alternatively, in the first process, an initial output of the transparent ice heater 505 may be determined based on a time elapsed from a completion of a water supply to on time of the transparent ice heater 505 or a temperature detected by the tray temperature sensor 410 at an on time of the transparent ice heater 505.

An output of the transparent ice heater 505 next to the initial output may be determined based on a representative temperature of the ice making chamber.

Alternatively, in the first process, an initial output of the transparent ice heater 505 may be determined based on a representative temperature of the ice making chamber at a time of a completion of a water supply or on time of the transparent ice heater 505.

In a process of performing the first process, an output of the transparent ice heater 505 may be determined at a set time interval. The set time is less than the reference time.

A temperature of the ice making chamber may be detected at an interval of a predetermined time (sampling time) within the set time range. The predetermined time is less than the set time.

Based on a temperature of the ice making chamber detected at an interval of predetermined time, a representative temperature within the set time range may be determined. At this time, a representative temperature may be, for example, an average temperature of the ice making chamber within the set time range. Alternatively, the representative temperature may be a middle temperature between a maximum temperature and a minimum temperature of the ice making chamber detected at an interval of predetermined time within the set time range.

As another example, a temperature of the ice making chamber may be periodically sensed at the set time interval or the interval of predetermined time, and a sensed temperature of the ice making chamber may be a representative temperature.

In either case, a representative temperature of the ice making chamber may be periodically determined, and an output of the transparent ice heater 505 may be determined based on a determined representative temperature.

For example, if a currently sensed representative temperature of the ice making chamber is −13 degrees Celsius, an output of the transparent ice heater 505 may be determined as A1. An output of the transparent ice heater 505 may be determined based on a next representative temperature of the ice making chamber.

In this embodiment, an output of the transparent ice heater 505 may be determined in advance for each temperature range to which a representative temperature of the ice making chamber belongs.

In FIG. 21, a group of outputs selected when a representative temperature of the ice making chamber is maintained within a predetermined temperature range may be referred to as an same output group. For example, A1 to A5 may be described as one same output group.

When a representative temperature of the ice making chamber is maintained within a first temperature range, a first output group may be selected. When a representative temperature of the ice making chamber is maintained within a second temperature range that is a temperature higher than the first temperature range, a second output group may be selected. When a representative temperature of the ice making chamber is maintained within a third temperature range that is higher than the second temperature range, a third output group may be selected.

During the first process, if a representative temperature of the ice making chamber increases or decreases, an output of the transparent ice heater 505 may be varied.

For example, during the first process, the transparent ice heater 505 may operate at an output Al determined immediately before. During a process in which the transparent ice heater 505 operates with an output A1, if a temperature of the ice making chamber increases to −12 degrees Celsius, an output of the transparent ice heater 505 may be changed to an output B1. Conversely, during a process in which the transparent ice heater 505 operates with an output A1, if a representative temperature of the ice making chamber is maintained, an output of the transparent ice heater 505 may be maintained at an output A1.

When the first process is completed, an output of the transparent ice heater 505 may be determined as an output corresponding to the second process. At this time, an output of the transparent ice heater 505 in the second process may also be determined based on a representative temperature of the ice making chamber.

While the first process is performed while a representative temperature of the ice making chamber is −12 degrees Celsius, when a representative temperature of the ice making chamber is maintained at −12 degrees Celsius at a start point of the second process, an output of the transparent ice heater 505 in the second process may be changed from an output B1 to an output B2 within the same output group. On the other hand, if a representative temperature of the ice making chamber increases to −11 degrees Celsius at a start of the second process, an output of the transparent ice heater 505 in the second process may be an output C2 of another output group.

If a representative temperature of the ice making chamber increases or decreases while the second process is being performed, an output of the transparent ice heater 505 may be varied. When the second process is started and a second reference time t2 has elapsed, the third process may be performed. The second reference time t2 may be equal to or different from the first reference time t1.

When the second process is ended, an output of the transparent ice heater 505 may be determined as an output corresponding to a third process. For example, if a representative temperature of the ice making chamber is −11 degrees Celsius and the second process is performed while a representative temperature of the ice making chamber is maintained at −11 degrees Celsius at a start of the third process, an output of the transparent ice heater 505 may be changed from an output C2 to an output C3 of the same output group at the third process. On the other hand, if a representative temperature of the ice making chamber increases to −10 degrees Celsius at a start of the third process, an output of the transparent ice heater 505 may be an output D3 of a different output group at the third process. If a representative temperature of the ice making chamber increases or decreases while the third process is performed, an output of the transparent ice heater 505 may be varied.

When the third process is started and a third reference time t3 has elapsed, the fourth process may be performed. The third reference time t3 may be equal to or different from the second reference time t2.

When the third process is ended, an output of the transparent ice heater 505 may be determined as an output corresponding to the fourth process. For example, when the third process is performed while a representative temperature of the ice making chamber is −10 degrees Celsius, if a representative temperature of the ice making chamber is maintained at −10 degrees Celsius at a start point of the fourth process, an output of the transparent ice heater 505 in the fourth process may be changed from an output D3 to an output D4 of the same output group. On the other hand, if a representative temperature of the ice making chamber increases to −9 degrees Celsius at a start point of the fourth process, an output of the transparent ice heater 505 in the fourth process may be an output E4 of another output group. In addition, if a representative temperature of the ice making chamber increases or decreases while the fourth process is performed, an output of the transparent ice heater 505 may be variable.

When the fourth process is started and a fourth reference time t4 has elapsed, the fifth process can be performed. The fourth reference time t4 may be equal to or different from the third reference time t3.

When the fourth process is ended, an output of the transparent ice heater 505 may be determined as an output corresponding to the fifth process. For example, when the fourth process is performed while a representative temperature of the ice making chamber is −9 degrees Celsius, if a representative temperature of the ice making chamber is maintained at −9 degrees Celsius at a start point of the fifth process, an output of the transparent ice heater 505 may be changed from an output E4 to an output E5 of the same output group in the fifth process. On the other hand, if a representative temperature of the ice making chamber increases to −8 degrees Celsius at a start point of the fifth process, an output of the transparent ice heater 505 in the fifth process may be an output F5 of another output group. If a representative temperature of the ice making chamber increases or decreases while the fifth process is performed, an output of the transparent ice heater 505 may be variable.

When the fifth process may be started and a fifth reference time t5 may be elapsed, and the fifth process may be ended. When the fifth process is ended, the controller 1000 may determine that an ice making is completed. The fifth reference time t5 may be greater than one or more of the first to fourth reference times (t1 to t4).

Meanwhile, in each of the processes, an output of the transparent ice heater 505 when a representative temperature of the ice making chamber is low may be greater than an output of the transparent ice heater 505 when a representative temperature of the ice making chamber is high.

An output of the transparent ice heater 505 of the second process within the same output group may be greater than an output of the transparent ice heater 505 of the first process. For example, an output B2 may be greater than an output B1, and an output C2 may be greater than an output C1. The same contents may be applied to remaining output groups.

When a representative temperature of the ice making chamber is maintained within a predetermined temperature range, an output of the transparent ice heater 505 may increase from an initial output as an ice making time elapses.

In the first process, a difference in output values of the transparent ice heater 505 of two adjacent output groups may be different.

For example, a difference between an output A1 when a representative temperature of the ice making chamber is maintained in a first temperature range and an output B1 when a representative temperature of the ice making chamber is maintained in a second temperature range having a temperature higher than the first temperature range may be different from a difference between the output B1 and an output C1 when a representative temperature of the ice making chamber is maintained in a third temperature range having a temperature higher than the second temperature range. Although not limited, a difference between an output B1 and an output C1 may be greater than a difference between an output A1 and an output B1.

In a first process, when a representative temperature of the ice making chamber increases, an output of the transparent ice heater 505 may decrease.

In the second process, an output of the transparent ice heater 505 when a representative temperature of the ice making chamber is low may be greater than an output of the transparent ice heater 505 when a representative temperature of the ice making chamber is high. In the second process, a difference between the output values of the transparent ice heater 505 for each of two adjacent output groups may be different. For example, a difference between an output A2 and an output B2 may be different from a difference between an output B2 and an output C2. Although not limited, a difference between an output B2 and an output C2 may be greater than a difference between an output A2 and an output B2.

In the same output group, an output of the transparent ice heater 505 of the third process may be less than an output of the transparent ice heater 505 of the second process. For example, an output B3 may be less than an output B2, an output C3 may be less than an output C2, and the same contents may be applied to remaining output groups.

Assuming that a representative temperature of the ice making chamber is maintained within a predetermined temperature range, an output of the transparent ice heater 505 may increase from an initial output and then decrease.

At this time, an output of the transparent ice heater 505 of the third process within an same output group may be equal to or different from an output of the second heater 505 of the first process.

In one output group, an output of the transparent ice heater 505 of the third process may be equal to an output of the transparent ice heater 505 of the first process. In another output group, an output of the transparent ice heater 505 of the third process may be greater than an output of the transparent ice heater 505 of the first process.

A lower limit value of a temperature range corresponding to another output group may be greater than an upper limit value of a temperature range corresponding to one of the output groups. For example, an output A3 may be equal to an output A1. An output F3 may be greater than an output F1.

In the third process, an output of the transparent ice heater 505 when a representative temperature of the ice making chamber is low may be greater than an output of the transparent ice heater 505 when a representative temperature of the ice making chamber is high.

In the same output group, an output of the transparent ice heater 505 of the fourth process may be less than an output of the transparent ice heater 505 of the third process. For example, an output B4 may be less than an output B3, and an output C4 may be less than an output C3. The same contents may be applied to remaining output groups.

An output of the transparent ice heater 505 of the fourth process within the same output group may be equal to or different from an output of the transparent ice heater 505 of the first process.

In one output group, an output of the transparent ice heater 505 of a fourth process may be less than an output of the transparent ice heater 505 of a first process. In another output group, an output of the transparent ice heater 505 of a fourth process may be the same as the output of the transparent ice heater 505 of a first process.

A lower limit value of a temperature range corresponding to another output group may be greater than an upper limit value of a temperature range corresponding to one of the output groups. For example, an output A4 may be less than an output A1. An output F4 may be equal to an output F1.

In the fourth process, an output of the transparent ice heater 505 when a representative temperature of the ice making chamber is low may be greater than an output of the transparent ice heater 505 when a representative temperature of the ice making chamber is high.

Within the same output group, an output of the transparent ice heater 505 of the fifth process may be less than an output of the transparent ice heater 505 of the fourth process. For example, an output B5 may be less than an output B4, and an output C5 may be less than an output C4. The same contents may be applied to remaining output groups. Therefore, within the same output group, an output of the transparent ice heater 505 may be increased from an initial output and then gradually decreased.

An output of the transparent ice heater 505 in the fifth process within the same output group may be a minimum output. The fifth process is a final process, and an output of the transparent ice heater 505 in the fifth process may be a final output (or final heating amount).

In the fifth process, an output of the transparent ice heater 505 when a representative temperature of the ice making chamber is low may be greater than an output of the transparent ice heater 505 when a representative temperature of the ice making chamber is high.

In summary, a variable pattern of an output of a second heater in one specific output group may be different from a variable pattern of an output of a second heater in another specific output group.

Meanwhile, in FIG. 21, the first process is performed in an initial ice making section to prevent scratches from occurring in ice generated, and an execution time of the first process may be referred to as a first ice making time. The first process be referred to as a first ice making section. An output of the transparent ice heater 505 in the first ice making section may be referred to as a first output (or first heating amount).

The second process is a process in which a second heater is operated with an output of a second heater increased compared to the first process to increase a transparency, and an execution time of the second execution time may be referred to as a second ice making time. The second process may be referred to as a second ice making section. An output of the transparent ice heater 505 in the second ice making section may be referred to as a second output (or second heating amount).

The third to fifth processes are processes in which an output of the transparent ice heater is gradually reduced compared to the second process, thereby minimizing a decrease in transparency while increasing an ice making rate. An execution time of the third to fifth processes may be referred to as a third ice making time. The third to fifth processes may be referred to as a third ice making section.

In the third ice making section, an output of the transparent ice heater 505 may be referred to as a third output (or third heating amount). The third output may be variable. For example, the third output may be gradually reduced.

When a temperature of the ice making chamber is lower than the reference temperature, an initial value of the third output may be equal to the first output. When a temperature of the ice making chamber is higher than the reference temperature, an initial value of the third output may be greater than the first output.

A difference value between the third ice making time and the second ice making time may be greater than A difference value between the first ice making time and the second ice making time.

An output change slope (for example, a decrease slope) of the transparent ice heater during the third ice making time may be varied based on a representative temperature of the ice making chamber.

For example, when a representative temperature of the ice making chamber is low (lower than the reference temperature), an output change slope may be greater than an output change slope when a representative temperature of the ice making chamber is high (higher than the reference temperature).

The controller 1000 may determine that an ice making is completed when the fifth process is completed and turn off the transparent ice heater 505.