AIR CONDITIONER CONTROL SYSTEM AND METHOD OF USE

Description

BACKGROUND

The present disclosure relates to air conditioners that are powered by a direct current power source and, more particularly, to control systems for such air conditioners and methods of using the control systems.

Air conditioners are commonly used to provide conditioned air within recreational vehicles, motor homes, travel trailers, caravans, folding camping trailers, truck campers, and other types of recreational vehicles, as well as within various types of boats and other non-residential applications such as trucks or trains. These air conditioners may be powered by a built-in generator that is hardwired to the recreational vehicle or boat, by a portable generator that sits outside the recreational vehicle, and by a “shore power” hookup that may be found at many campsites, recreational vehicle parks, and boat docks.

Recreational vehicle and marine air conditioners that use a direct current power source are becoming increasingly popular because advancements in lithium-ion battery technology and solar panel technology allow for greater power storage. The more common type of direct current air conditioner uses an inverter to convert the direct current from the power source to an alternating current, which then drives the air conditioner's vapor-compression refrigeration system. When the direct power source is a battery bank or solar panel, the inverter may continue to draw current from the battery bank or solar panel even after the air conditioner has reached its set point and the air conditioner's refrigeration system is idled. This current draw can create a system inefficiency by resulting in quicker depletion of the energy stored in the battery bank or solar panel. Additionally, this type of direct current air conditioner is expensive.

Another type of direct current air conditioner drives the vapor-compression refrigeration system using direct current. This type of direct current air conditioner tends to be more expensive than conventional alternating current air conditioners because the direct current compressor and other components of the vapor-compression refrigeration system tend to be specialty products that do not share the same economies of scale of conventional alternating current compressors and components.

A need thus exists for more efficient use of the energy stored in the battery bank or solar panel that serves as the power source for recreational vehicle and marine air conditioners that use lower cost alternating current compressors and components.

SUMMARY

Embodiments of the current disclosure address one or more of the above-mentioned problems and provide a distinct advance in the art of air conditioner units, such as those used in recreational vehicles. In some embodiments, an air conditioner unit includes a thermostat, a compressor driven by an alternating current voltage, and a controller. The controller may be electrically and/or communicably coupled to receive control signals from the thermostat and direct current voltage from a direct current source. Furthermore, the controller may have an inverter function that converts the direct current voltage to the alternating current voltage, and based on the control signals received from the thermostat, selectively switches the compressor between a first mode in which the alternating current voltage is provided to the compressor and second mode in which the controller prevents or reduces the drawing of current from the direct current source when the thermostat senses a desired temperature.

In other embodiments, an air conditioner unit includes a thermostat, a fan motor driven by an alternating current voltage, a compressor driven by the alternating current voltage, and a controller that receives control signals from the thermostat and direct current voltage from a direct current source. The controller has an inverter function that converts the direct current voltage to the alternating current voltage. Based on the control signals received from the thermostat, the controller selectively switches the fan motor to a high speed or a low speed that is less than the high speed. Furthermore, based on the control signals received from the thermostat, the controller selectively switches the compressor between a first mode in which the alternating current voltage is provided to the compressor and a second mode in which the controller reduces or prevents drawing of current from the direct current source when the thermostat senses a desired temperature.

In yet another embodiment, a method of operating an alternating current air conditioner unit with a direct current power source includes the steps of receiving with a controller a direct current voltage from a direct current source and converting the direct current voltage to an alternating current voltage via an inverter function of the controller. The alternating current voltage selectively drives a fan motor and a compressor of the alternating current air conditioner unit. The method may further comprise the steps of receiving with the controller control signals from a thermostat and, based on the control signals received from the thermostat, selectively switching the fan motor, via the controller, to either a high speed or a low speed that is less than the high speed. Additionally, the method may include, based on the control signals received from the thermostat, selectively switching the compressor, via the controller, between a first mode in which the alternating current voltage is provided to the compressor and a second mode in which the controller prevents the drawing of current from the direct current source when the thermostat senses a desired temperature.

This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Other aspects and advantages of the current disclosure will be apparent from the following detailed description of the embodiments and the accompanying drawing figures.

BRIEF DESCRIPTION OF DRAWINGS

Embodiments of the current disclosure are described in detail below with reference to the attached drawing figures, wherein:

FIG. 1 is a block diagram of an air conditioner unit and inputs thereof in accordance with an embodiment of the present disclosure;

FIG. 2 is a schematic block diagram of a controller of the air conditioner unit of FIG. 1 in accordance with an embodiment of the present disclosure; and

FIG. 3 is a flow diagram of a method of operation of the air conditioner unit of FIG. 1 in accordance with an embodiment of the present disclosure.

The drawing figures do not limit the current disclosure to the specific embodiments disclosed and described herein. The drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present disclosure.

DETAILED DESCRIPTION

The following detailed description of the technology references the accompanying drawings that illustrate specific embodiments in which the technology can be practiced. The embodiments are intended to describe aspects of the technology in sufficient detail to enable those skilled in the art to practice the technology. Other embodiments can be utilized and changes can be made without departing from the scope of the current disclosure. The following detailed description is, therefore, not to be taken in a limiting sense. The scope of the current disclosure is defined only by the appended claims, along with the full scope of equivalents to which such claims are entitled.

The present disclosure is generally directed toward an alternating current (“AC”) air conditioner unit powered by a direct current (“DC”) power source and a control system for the air conditioner system. The air condition unit described herein provides a more efficient use of stored energy, such as energy stored in a battery bank or solar panel that serves as a power source for recreational vehicles, marine air conditioners, or the like. Specifically, the control system for the air conditioner unit described herein is configured to invert a signal from a DC source into an AC source used by a compressor and that may also be used by a soft-start function of the air conditioner unit, and the control system is further configured to control when an inverter function of the controller is placed in idle or a mode that reduces or prevents current draw from the direct current source 20 based on one or more sensed conditions.

Embodiments of the present disclosure may include an air conditioner unit 10 as depicted in FIG. 1. Specifically, in some example embodiments, the air conditioner unit 10 may include or be associated with one or more of a compressor 12, a fan motor 14, a reversing valve 16, a thermostat 18, a direct current source 20, an indoor coil temperature sensor 22, an outdoor coil temperature sensor 24, and a controller 26. Other traditional components of air conditioner units may also be included as components of the air conditioner unit 10 without departing from the scope of the present disclosure, such as an outdoor coil (also known as a condenser or a condenser coil), an indoor coil (also known as an evaporator or an evaporator coil), fans, a heat pump, a refrigerant or a refrigerant source, and the like.

The compressor 12 is an air conditioner compressor operated via alternating current. The compressor 12 may be part of a condenser unit of the air conditioner unit 10 and may be configured to compress refrigerant vapor. Specifically, the compressor 12 is configured to transfer heat from a refrigerant (e.g., a liquid refrigerant such as freon, R22, R410A, R134A, R32, and the like) to a condenser (not shown) of the air conditioner unit 10.

The fan motor 14 may be a motor or motors configured to rotate one or more fans or scrolls of the air conditioner unit 10. The fan motor 14 is operated via alternating current and may drive one or more fans or scrolls (not shown) which blow air in and/or out of a recreational vehicle or any space to be cooled thereby. The fan motor 14 may thus be configured to move hot air out of the recreational vehicle and/or supply cool air into the recreational vehicle.

The reversing valve, 16 also known in the art as a heat pump reversing valve, may be operated via alternating current and controls the direction of refrigerant flow. For example, the reversing valve 16 can include a sliding cylinder that changes which tubes of the air conditioner unit 10 align to allow or block flow of the refrigerant. The reversing valve 16 functions to switch the air conditioner unit 10 or the heat pump thereof between a heating mode and a cooling mode. Specifically, in the heating mode, the refrigerant is directed to flow from the compressor 12 to the indoor coils, and in the cooling mode, the refrigerant is directed to flow to the outdoor coils.

The thermostat 18 is a climate control device and is electrically or otherwise communicably associated with the controller 26. The thermostat 18 is configured to control when and how long the compressor 12 and fan motor 14 run, based on the temperature within a cabin, compartment, or other space of the recreational vehicle. The thermostat 18 is configured to cause a desired temperature (such as a temperature input or adjusted by a user) to be obtained and maintained by turning the air conditioner unit 10 on and off (or into an idle or stand-by mode). In some example embodiments, the thermostat 18 gives control signals Y, GH, GL, and WHP, all of which are 12V DC signals. Item B in FIG. 1 may indicate a ground point for the thermostat 18. Y operates as a compressor control signal during refrigeration, and its control logic may indicate that when the Y output is equal to 12V, the compressor 12 operates, and when the Y output is equal to 0V, the compressor 12 does not operate and/or is placed into the idle or stand-by mode (e.g., the second mode as described herein). GH and GL are control signals for the fan motor 14, and their control logic is provided in the Table 1 below:

Furthermore, WHP operates as the compressor control signal during heating, and its control logic may indicate that when WHP=12V, the compressor 12 and the reversing valve 16 operate, but when WHP=0V, the compressor 12 and the reversing valve 16 do not operate.

The direct current source 20 can include a direct current input port and/or any direct current source such as batteries, solar panels, or other direct current sources known or that may be developed in the art. In some embodiments, direct current batteries associated with the recreational vehicle may be used by the air conditioner unit 10, with an inverter function of the controller 26 being used to convert the direct current voltage into alternating current voltage, such as 115 VAC/60 Hz or 230 VAC/50 Hz AC power for the components of the air conditioner unit 10 that operate on alternating current voltage, such as the compressor 12, the fan motor 14, and/or the reversing valve 16. In some embodiments, the direct current source 20 is electrically coupled to the controller 26, providing the controller 26 with 48 VDC, or any value between 9.5 VDC and 58 VDC, and the load of the direct current source 20 is the compressor 12, the fan motor 14 (e.g., a two-speed AC fan), and the reversing valve 16. Furthermore, the power requirement for the inverter function of the controller 26 may be 2500 W. However, other amounts of power or current may be utilized by the air conditioner unit 10 without departing from the scope of the present disclosure. In some alternative embodiments, the air conditioner unit 10 may optionally provide an alternating current input (in addition to the direct current input) for receiving AC voltage, automatically passing the power through to the 108-132 VAC air conditioner unit components. This advantageously allows the air conditioner unit 10 the flexibility to be powered by direct current or alternating current power sources.

The indoor coil temperature sensor 22 may be a sensor configured for measuring the temperature of air passing over the indoor coil of the air conditioner unit 10. In some embodiments, when the temperature reading of the indoor coil temperature sensor 22 is below or equal to 28±3° F. and Y=12V, the compressor operation will be stopped indicating that the indoor coil has frosted. The compressor will resume operation at 55±3° F. if Y=12V which indicates that the indoor coil has been defrosted. In some embodiments, a defrost temperature sensor of the air conditioner unit (e.g., the indoor coil sensor and/or the outdoor coil sensor) may be a negative temperature coefficient (NTC) type R25=10Kohm, B=3890. However, other temperature sensors may be used without departing from the scope of the disclosure.

Likewise, the outdoor coil temperature sensor 24 may be a sensor configured for measuring the temperature of air passing over the outdoor coil of the air conditioner unit 10. When the temperature reading of the outdoor temp sensor below 18±3° F. and WHP=12V, the compressor will stop, and the fan speed becomes low indicating that the outdoor coil has frosted and needs to be defrosted. When the temperature sensed by the outdoor coil temperature sensor 24 reaches above the 36° F. and WHP=12V the compressor works again and the fan speed is change to the desired speed, indicating that the outdoor coil has been defrosted. In some embodiments, a defrost temperature sensor of the air conditioner unit (e.g., the indoor coil sensor and/or the outdoor coil sensor) may be an NTC type R25=10Kohm, B=3890. However, other temperature sensors may be used without departing from the scope of the disclosure.

The controller 26 may include any control system and/or controller/inverter circuit board which receives signals from a climate control device (e.g., the thermostat 18, coil temperature sensors 22, 24) and manages output power to the compressor 12, fan motor, 14 and/or reversing valve 16 accordingly. Unlike prior art systems, the controller 26 does not continue to draw current from the direct current source 20 (e.g., battery bank or solar panel) after the air conditioner unit 10 has reached its set point (e.g., desired temperature sensed by the thermostat 18) and the air conditioner unit's refrigeration system is idled. Rather, the controller 26 operates based on the inputs from the thermostat 18 as later described herein and reduces or prevents current draw from the direct current source 20 once the air conditioner unit 10 reaches its set point. The controller 26 may be configured to operate as an inverter or may have an inverter function operable to convert direct current voltage to alternating current voltage for various components of the air conditioner unit 10. For example, the controller 26 and/or the inverter may invert 9.5 VDC-58 VDC power (e.g., 48 VDC power) to run a 108-132 VAC air conditioner. The inverter and/or other functions of the controller 26 may be controlled by signals received from the thermostat 18, the indoor coil temperature sensor 22, and the outdoor coil sensor, and in some embodiments may further include overcurrent and overload protection as known in the art. Example parameters of the controller 26 and/or the inverter or inverter function therein are provided in Table 2 below:

Additionally, the controller's inverter may have a soft-start function activated by the controller 26 when the compressor 12 starts. Specifically, the controller 26 soft starts and/or manages the compressor 12 of the air conditioner unit 10. The inclusion of a soft start function of the compressor 12 advantageously prevents high current at startup of the air conditioner unit 10. The controller 26 may also control and/or mange a speed of the fan motor 14, which may be driven by alternating current voltage. The controller 26 as described herein advantageously eliminates the need for an individual soft start circuit board/hardware that is separate from other circuit boards or control hardware of the air conditioner unit.

A defrosting function of the controller 26 and/or the inverter thereof may be configured to operate based on input from the thermostat 18 and/or the indoor or outdoor coil temperature sensors 22, 24. That is, when sensed temperatures of one or more of the coils are at a range indicative of undesirable frosting of one or more of the coils, also referred to herein as a frosting temperature, the defrosting function may operate to stop the compressor 12 and/or switch the fan motor 14 to operate on a low speed for a time until the sensed temperature is warm enough that it indicates defrosting has occurred, also referred to herein as a defrosting temperature, and the air conditioner unit 10 may be safely operated again.

An example embodiment of the controller 26 is depicted in FIG. 2, and may include various filters, gain circuitry, integrated circuits, MOSFETS, relays, and/or various DC to AC converter circuitry known in the art. For example, an input power filter may receive 48 VDC from the direct current source 20 and may provide power to a DC-DC power supply as well as a gain or voltage increase unit. The DC-DC power supply may provide 12 VDC to various components and circuitry such as a relay driver. The voltage increase unit may provide output to an input current voltage detecting circuit and/or a power switch unit including various MOSFETS, for example, or other circuitry configured for inverting the direct current to an alternating current. The output from the power switch unit may also be filtered through an output filter, which may then output, for example, 120 VAC at 60 Hz to one or more relays as described herein, as well as an output current and voltage detecting circuit. However, the power switch unit, the output filter, and/or other DC to AC voltage conversion circuitry may output other quantities of alternating current voltage without departing from the scope of the disclosure.

The input current voltage detecting circuit may output an amplified direct current signal to a first microcontroller unit (MCU) circuit and the output current and voltage detecting circuitry may output an alternating current signal (converted from the amplified direct current signal) to the first MCU circuit for processing thereby. The first MCU circuit may output a signal to a driver for power switch, which may then provide an output signal to the power switch unit. A communication circuit and/or a light emitting diode (LED) display may receive output signals processed by the first MCU circuit, and the communication circuit may function to send and receive signals between the first MCU circuit and a second MCU circuit. The second MCU circuit may receive various signals from the thermostat 18, such as those associated with various temperatures or the like. Furthermore, the second MCU circuit may receive indoor coil temperatures and/or outdoor coil temperatures via a temperature detector and/or one or more of the indoor coil temperature sensor 22 and the outdoor coil temperature sensor 24. In some embodiments, the MCU1 may be SH79F1611 by Sinowealth and the MCU2 may be CW32F002 by Kingsemi. However, other circuitry or microcontrollers may be used without departing from the scope of the disclosure.

Regarding the relays depicted in FIG. 2, the second MCU circuit may output control signals to the relay driver, which may then output control signals to any one or more of the following drivers for the fan motor 14, the compressor 12, and/or the reversing valve 16. For example, the relays may include a relay for high fan, a relay for low fan, a relay for the reversing valve 16, and a relay for the compressor 12. In some embodiments, the relay for the compressor 12 may output on and off or start and stop commands via a silicon-controlled rectifier (SCR) circuit to the compressor 12.

In some embodiments, the relay driver may be powered via direct current (e.g., 12 VDC), the other relays may be powered by alternating current (e.g., 120 VAC/60 Hz). The relay for high fan may output high fan on/off signals to the fan motor 14, while the relay for low fan may output on/off signals to the fan motor 14. Similarly, the relay for the reversing valve 16 may provide switching signals to the reversing valve 16 to switch the direction of the flow of refrigerant, while the relay for the compressor 12 may output start/stop or on/off signals to the compressor 12 directly or via the SCR circuit. During an initial start-up of the compressor 12, the controller's soft start function may operate by the SCR gradually decreasing a triggering angle allowing increasing of the voltage applied to the compressor 12 until the compressor 12 reaches its full operating voltage. In some embodiments, excessive start current may trigger the controller 26 or the inverter function thereof to enter a protection mode (e.g., the overvoltage protection mode of Table 2).

Some of the components of the air conditioner unit 10, such as the controller 26 and/or the thermostat 18, can be provided as a kit to be added to an existing alternating current powered air conditioner unit to provide the functionality described herein, such as the ability to be powered by direct current voltage. Conversely, the controller 26 and the thermostat 18 may be integrated into the air conditioner unit 10 at the time of its manufacture.

In use, the air conditioner unit 10 or components thereof such as the controller 26 may receive a direct current voltage from the direct current source 20, receive control signals from the thermostat 18 or other temperature sensors (e.g., the indoor coil temperature sensor 22 and/or the outdoor coil temperature sensor 24), and convert direct current voltage to alternating current voltage for selectively driving the compressor 12, the fan motor 14 and/or the reversing valve 16 based on signals from the thermostat 18 and/or the indoor or outdoor coil temperature sensors 22, 24. In some embodiments, based on the control signals received from the thermostat 18, the controller 26 may selectively switch the fan motor 14 to a high speed or a low speed that is less than the high speed. Furthermore, based on the control signals received from the thermostat 18, the controller 26 may selectively switch the compressor 12 between a first and a second mode, where the first mode is an active mode in which the alternating current voltage is provided to the compressor 12 and the second mode is an idle or stopped mode in which the controller prevents or reduces the drawing of current from the direct current source 20 when the thermostat 18 senses a desired temperature. In some embodiments, in the second mode, the controller reduces an amount of current drawn from the direct current source 20 to a value that is less than the amount of current drawn from the direct current source 20 when the controller 26 is operating the compressor 12 in the first mode.

Furthermore, as described in examples herein, the controller 26 may utilize a soft start function, instructing the fan motor 14 to begin rotating and then activating the compressor 12 to run after a predetermined period of delay. Additionally, or alternatively, the soft start function may gradually ramping up voltage applied to the compressor 12 for a pre-determined number of seconds until reaching 100% of the alternating current voltage that drives the compressor. In some embodiments, a defrosting function of the controller 26 may be used for stopping or reducing operation of the compressor 12 or reducing a speed of the fan motor 14 when a frosting temperature is reached by the indoor coil temperature sensor 22 and/or the outdoor coil temperature sensor 24. The defrosting function may resume operation of the compressor 12 or increase the speed of the fan motor 14 when a defrosting temperature is reached by the indoor coil temperature sensor 22 and/or the outdoor coil temperature sensor 24. These and other uses of the air conditioner unit described above are described below.

The flow chart of FIG. 3 depicts in more detail the steps of an exemplary method 300 for operating alternating current components of an air conditioner unit with a direct current source 20 according to one or more embodiments of the present disclosure. In some embodiments, various steps may be omitted and/or steps may occur out of the order depicted in FIG. 3 without departing from the scope of the disclosure. For example, two blocks shown in succession in FIG. 3 may in fact be executed substantially concurrently, or blocks may sometimes be executed in the reverse order depending upon the functionality involved. The steps may be performed by the controller 26 of the air conditioner unit 10 and/or other components of the air conditioner unit 10 via hardware, software, firmware, or combinations thereof. Furthermore, some or all of the steps may be implemented as instructions, code, code segments, code statements, algorithms, functions, software modules, a program, an application, an app, a process, a service, a daemon, or the like, and may be stored on a computer-readable storage medium such as one or more of the MCUs in FIG. 2.

The method 300 depicts a start point at block 302 and a step of reading one or more signals from the thermostat 18, as depicted in block 304. For example, the controller 26 may receive any one of the signals described above as being output by the thermostat 18 (e.g., Y, GH, GL, or WHP). Another step of the method 300 includes determining if one of the thermostat signals is activated, as depicted in block 306. For example, as described above, any of Y, GH, GL, or WHP may be considered activated when outputting a predetermined voltage, such as the 12V described in the example embodiments above. However, the thermostat 18 may be configured to output other voltages and the controller 26 may be configured to recognize different voltages as activated other than 12V without departing from the scope of the disclosure.

In some embodiments of the method 300, if none of the thermostat signals is activated, a step of stopping the inverter is executed, as depicted in block 308. However, if any of the thermostat signals are activated, the method 300 may include a step of starting the inverter, as depicted in block 310. The method 300 may then include a step of checking that the voltage is within pre-defined operational limits, as depicted in block 312, with the method proceeding to block 314 if the voltage is within pre-defined operational limits and otherwise proceeding back to block 310 if the voltage is not within pre-defined operational limits. However, block 312 may be omitted in some embodiments of the disclosure without departing from the scope of the disclosure as described herein.

Method 300 may also include the steps of determining if GH is activated, as depicted in block 314, and/or determining of GL is activated, as depicted in block 316. As indicated in Table 1 above, if GH is activated, the method 300 responds with a step of activating the high fan relay, as depicted in block 318. The high fan relay may be activated if GH is activated, regardless of whether or not GL is activated. However, if GH is not activated, but GL is activated, the method 300 responds with a step of activating the low fan relay, as depicted in block 320. As described above, GH and GL are control signals for the fan motor 14, and their control logic operates when the fan is either operating on high, operating on low, or not operating. In some embodiments, other fan speeds besides high and low with other control logic for activation may be used without departing from the scope of the disclosure. Furthermore, the precise fan motor speeds selected for high and low may vary for different models of air conditioner units depending on the cubic feet the air conditioner unit is designed to cool and depending on the desired airflow, measured in cubic feet per minute (CFM). In one example embodiment, the fan motor 14 may operate the fan or fans on high at a speed of 1625 RPM (±25 RPM) and on low at a speed of 1525 RPM (±25 RPM). However, other high and/or low speeds may be used without departing from the scope of the disclosure herein.

The method 300 may further comprise a step of determining if Y is activated, as depicted in block 322, and when Y is newly activated, waiting for a predefined time (e.g., 30 seconds or 3 minutes), as depicted in block 324, and soft starting the compressor 12, as depicted in block 326. Note that Y is newly activated if it has gone from a non-activated state (e.g., 0V) to an activated state (e.g., 12V). That is, the method steps of blocks 324 and 326 specifically apply upon Y being newly activated. Furthermore, once it is determined that Y is no longer activated, then power to the compressor 12 may be shut off or be placed into idle mode or the second mode as described above. As noted above, the controller 26 is configured to convert direct current voltage (e.g., 9.5 VDC-58 VDC or 48 VDC) into alternating current voltage, such as 115 VAC/60 Hz or 230 VAC/50 Hz AC power for the air conditioner unit's components that operate on alternating current, such as the compressor 12, the fan motor 14, and/or the reversing valve 16. Thus, the AC power, converted by the controller 26 from DC power, is provided to the compressor 12 when Y is active.

As described above, the thermostat signal Y may operate as a compressor control signal during refrigeration, and its control logic may indicate that when the Y output is equal to 12V (or another control voltage amount), the compressor 12 operates, and when the Y output is equal to 0V, the compressor 12 does not operate or is placed into stand-by or idle mode (e.g., the second mode described above) and does not draw current from the direct current source 20. Soft starting the compressor 12 may be controlled via the controller 26 and/or the inverter thereof. The soft start function may, for instance, be configured to gradually increase the voltage and current provided to the compressor 12, reducing strain on the air conditioner unit 10 and protecting the compressor 12 from damage. That is, the controller 26 may be configured to gradually increase the power draw until the compressor 12 eventually is drawing full power from the inverter, so that current spikes do not overload the air conditioner unit 10 or use an excessive amount of the direct current source 20 (e.g., so that the battery is used more efficiently and does not die as quickly). The soft start function ramp-up may include, for example, linearly ramping up from OVAC to full desired VAC voltage (e.g., 115 VAC/60 Hz or 230 VAC/50 Hz AC) in a preset, programmed duration (e.g., one second or 0.5 seconds to 2 seconds). In some embodiments, the first MCU or the second MCU of FIG. 2 described above may control the soft start function described herein. Integrating this soft start function into the controller 26 as described herein advantageously eliminates the need for an individual soft start circuit board/hardware that is separate from other circuit boards or control hardware of the air conditioner unit, providing a cost and space savings over prior art systems.

The method 300 also includes the steps of detecting the coil temperature, as in block 328, and determining if the coil temperature has reached a particular limit, as depicted in block 330. If the particular limit of the coil temperature is reached, the method 300 includes activating the defrost program, as depicted in block 332. This defrost program or defrosting function of the controller 26 and/or the inverter thereof may operate based on input from the thermostat 18 and/or the indoor or outdoor coil temperature sensors 22, 24. In one example embodiment of the disclosure, when the indoor coil temperature sensor 22 provides a temperature of less than 28±3° F. and Y equals 12V, the compressor 12 is instructed by the controller 26 to stop operation, because this may indicate that the indoor coil has frosted. In this example embodiment, once the indoor coil temperature sensor 22 provides a temperature greater than 55±3° F. and Y equals 12V, then the controller 26 provides a signal to the compressor 12 to resume operation, as this may indicate that the indoor coil has been defrosted. Additionally, or alternatively, in some example embodiments, when the outdoor coil temperature sensor 24 provides a temperature of less than 18±3° F. and the WHP equals 12V, the compressor 12 and the fan motor 14 are switched via the controller 26 to low air because the outdoor coil is assumed to have frosted and thus needs to be defrosted. Then, when the outdoor coil temperature sensor 24 provides a temperature of greater than 36° F. and the WHP equals 12V, the controller 26 may activate the compressor 12 again and switch the fan motor 14 back to high air or its set wind speed because the outdoor coil has been defrosted.

Note that the defrost program or defrosting function may override signals associated with other method steps provided herein, taking priority over other method steps of functions described herein. For example, even if GH is activated, the fan may still be switched to low speed instead of high speed if the defrosting function is operating, as described above.

The method steps for method 300 may continue to use thermostat signals and temperature sensor signals to operate as described herein throughout operation of the air conditioner unit 10, with certain functions or method steps only applying under particular conditions. For example, as described above, the method steps in blocks 324 and 326 may only apply when Y has newly changed from a non-activated state to an activated state. Similarly, the defrost program only activates in response to certain temperature conditions and then continues to run until a desired temperature is sensed by the indoor or outdoor coil temperature sensors 22, 24.

Additional Considerations

Throughout this specification, references to “one embodiment”, “an embodiment”, or “embodiments” mean that the feature or features being referred to are included in at least one embodiment of the technology. Separate references to “one embodiment”, “an embodiment”, or “embodiments” in this description do not necessarily refer to the same embodiment and are also not mutually exclusive unless so stated and/or except as will be readily apparent to those skilled in the art from the description. For example, a feature, structure, act, etc. described in one embodiment may also be included in other embodiments, but is not necessarily included. Thus, the current disclosure can include a variety of combinations and/or integrations of the embodiments described herein.

Although specific circuitry and operating voltage values are provided in FIG. 2, these are merely exemplary components for accomplishing the functions of the controller 26 as further described herein. For example, other microprocessors and/or other equivalent circuitry can be included in the controller 26 without departing from the scope of the disclosure. Furthermore, some of the components may be omitted or other circuitry such as filters, gain circuitry, and the like may be added to the controller 26 described herein without departing from the scope of the disclosure. Specifically, in the art of integrated circuitry, numerous circuit combinations known in the art may be utilized to achieve identical functions, such as signal amplification, conversion, comparison, and/or filtering.

Although the present application sets forth a detailed description of numerous different embodiments, it should be understood that the legal scope of the description is defined by the words of the claims set forth at the end of this patent and equivalents. The detailed description is to be construed as exemplary only and does not describe every possible embodiment since describing every possible embodiment would be impractical. Numerous alternative embodiments may be implemented, using either current technology or technology developed after the filing date of this patent, which would still fall within the scope of the claims.

Throughout this specification, plural instances may implement components, operations, or structures described as a single instance. Although individual operations of one or more methods are illustrated and described as separate operations, one or more of the individual operations may be performed concurrently, and nothing requires that the operations be performed in the order illustrated. Structures and functionality presented as separate components in example configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements fall within the scope of the subject matter herein.

Certain embodiments are described herein as including logic or a number of routines, subroutines, applications, or instructions. These may constitute either software (e.g., code embodied on a machine-readable medium or in a transmission signal) or hardware. In hardware, the routines, etc., are tangible units capable of performing certain operations and may be configured or arranged in a certain manner. In example embodiments, one or more computer systems (e.g., a standalone, client or server computer system) or one or more hardware modules of a computer system (e.g., a processor or a group of processors) may be configured by software (e.g., an application or application portion) as computer hardware that operates to perform certain operations as described herein.

In various embodiments, computer hardware, such as a processing element, may be implemented as special purpose or as general purpose. For example, the controller 26 may be or may comprise any processing element and may comprise dedicated circuitry or logic that is permanently configured, such as an application-specific integrated circuit (ASIC), or indefinitely configured, such as an FPGA, to perform certain operations. The controller 26 or the processing element may also comprise programmable logic or circuitry (e.g., as encompassed within a general-purpose processor or other programmable processor) that is temporarily configured by software to perform certain operations. It will be appreciated that the decision to implement the controller 26 or the processing element as special purpose, in dedicated and permanently configured circuitry, or as general purpose (e.g., configured by software) may be driven by cost and time considerations.

Accordingly, the term “processing element” or equivalents thereof should be understood to encompass a tangible entity, be that an entity that is physically constructed, permanently configured (e.g., hardwired), or temporarily configured (e.g., programmed) to operate in a certain manner or to perform certain operations described herein. Considering embodiments in which the processing element is temporarily configured (e.g., programmed), each of the processing elements need not be configured or instantiated at any one instance in time. For example, where the processing element comprises a general-purpose processor configured using software, the general-purpose processor may be configured as respective different processing elements at different times. Software may accordingly configure the processing element to constitute a particular hardware configuration at one instance of time and to constitute a different hardware configuration at a different instance of time.

Computer hardware components, such as communication elements, memory elements, processing elements, and the like, may provide information to, and receive information from, other computer hardware components. Accordingly, the described computer hardware components may be regarded as being communicatively coupled. Where multiple of such computer hardware components exist contemporaneously, communications may be achieved through signal transmission (e.g., over appropriate circuits and buses) that connect the computer hardware components. In embodiments in which multiple computer hardware components are configured or instantiated at different times, communications between such computer hardware components may be achieved, for example, through the storage and retrieval of information in memory structures to which the multiple computer hardware components have access. For example, one computer hardware component may perform an operation and store the output of that operation in a memory device to which it is communicatively coupled. A further computer hardware component may then, at a later time, access the memory device to retrieve and process the stored output. Computer hardware components may also initiate communications with input or output devices, and may operate on a resource (e.g., a collection of information).

The various operations of example methods described herein may be performed, at least partially, by one or more processing elements or controllers that are temporarily configured (e.g., by software) or permanently configured to perform the relevant operations. Whether temporarily or permanently configured, such processing elements or controllers may constitute processing element-implemented modules that operate to perform one or more operations or functions. The modules referred to herein may, in some example embodiments, comprise controller-implemented modules or processing element-implemented modules.

Similarly, the methods or routines described herein may be at least partially controller-implemented or processing element-implemented. For example, at least some of the operations of a method may be performed by one or more processing elements, controllers, controller-implemented hardware modules, or processing element-implemented hardware modules. The performance of certain of the operations may be distributed among the one or more processing elements, not only residing within a single machine, but deployed across a number of machines. In some example embodiments, the processing elements may be located in a single location (e.g., within a home environment, an office environment or as a server farm), while in other embodiments the processing elements may be distributed across a number of locations.

Unless specifically stated otherwise, discussions herein using words such as “processing,” “computing,” “calculating,” “determining,” “presenting,” “displaying,” or the like may refer to actions or processes of a machine (e.g., a computer with a processing element and other computer hardware components) that manipulates or transforms data represented as physical (e.g., electronic, magnetic, or optical) quantities within one or more memories (e.g., volatile memory, non-volatile memory, or a combination thereof), registers, or other machine components that receive, store, transmit, or display information.

As used herein, the terms “comprises,” “comprising,” “includes,” “including,” “has,” “having” or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

The patent claims at the end of this patent application are not intended to be construed under 35 U.S.C. § 112(f) unless traditional means-plus-function language is expressly recited, such as “means for” or “step for” language being explicitly recited in the claim(s).

Although the technology has been described with reference to the embodiments illustrated in the attached drawing figures, it is noted that equivalents may be employed and substitutions made herein without departing from the scope of the technology as recited in the claims.

Having thus described various embodiments of the technology, what is claimed as new and desired to be protected by Letters Patent includes the following: