AIR CONDITIONER

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of International Application No. PCT/JP2023/006998, filed Feb. 27, 2023, the entire contents of which are incorporated herein by reference.

FIELD

The present invention relates to an air conditioner technology.

BACKGROUND

There is an air conditioner including a refrigerant shutoff valve. For example, Patent Document 1 discloses an air conditioner in which a mechanism for shutting off a flow of a refrigerant flowing through a liquid refrigerant pipe and a gas refrigerant pipe is provided in the liquid refrigerant pipe and the gas refrigerant pipe connecting an outdoor unit including a compressor and a plurality of indoor units including an indoor expansion valve and an indoor heat exchanger, and the shutoff mechanism operates when the refrigerant leaks from the indoor unit side to suppress a refrigerant leak from the indoor unit side.

In the technology disclosed in Patent Document 1, in order to confirm an operation of the shutoff mechanism including its shutoff performance, the compressor is operated in a cooling cycle state and the shutoff mechanism is opened and closed to determine whether or not the shutoff mechanism is operating normally including the shutoff performance.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram showing a configuration of an air conditioner according to the present embodiment.

FIG. 2 is a diagram showing a configuration of a leak detector.

FIG. 3 is a flowchart showing a flow of processing executed by an outdoor unit control unit and the like.

FIG. 4 is a diagram showing an example of grouping.

FIG. 5A is a flowchart showing a flow of a unit inspection mode.

FIG. 5B is a flowchart showing a flow of the unit inspection mode.

DESCRIPTION OF EMBODIMENTS

Hereinafter, an air conditioner of an embodiment will be described with reference to the drawings.

An air conditioner according to an embodiment includes: an outdoor unit that includes an outdoor expansion valve, an outdoor heat exchanger, a four-way valve, and a compressor; an indoor unit that includes an indoor heat exchanger and an indoor expansion valve that adjusts an amount of a refrigerant flowing through the indoor heat exchanger; a shutoff unit that connects the outdoor unit and the indoor unit in parallel to the same refrigerant piping system, either singly or in a plurality of connections, and that incorporates a plurality of shutoff mechanisms configured to shut off a flow of the refrigerant between the outdoor unit and the indoor unit; and a refrigerant leak detector electrically connected to the indoor unit.

The shutoff unit is connected to the outdoor unit via at least one liquid pipe through which a liquid refrigerant flows and at least one gas pipe through which a gas refrigerant flows, and is connected to the indoor unit via at least one liquid pipe through which the liquid refrigerant flows and at least one gas pipe through which the gas refrigerant flows, and the air conditioner includes: a simple inspection mode for confirming a refrigerant leak detection operation of the refrigerant leak detector; and a detailed inspection mode for confirming, by operating the compressor, that each of the plurality of shutoff mechanisms incorporated in the shutoff unit is operating normally, and is capable of selectively executing the simple inspection mode and the detailed inspection mode.

First Embodiment

FIG. 1 is a diagram showing a configuration of an air conditioner 1 according to the present embodiment. Note that, FIG. 1 shows one outdoor unit and three indoor units as an example, but the number of units is not limited thereto. Also, the refrigeration cycle of FIG. 1 is an example, and the invention is not limited to the refrigeration cycle. The air conditioner 1 includes indoor units 2, 3, 4 and an outdoor unit 5. Also, the outdoor unit 5 is configured to be connected to the indoor units 2, 3 and 4 disposed in parallel by refrigerant piping. In the outdoor unit 5, a compressor 54, a four-way valve 53 for switching between cooling and heating operations, an outdoor heat exchanger 52, and an outdoor expansion valve 51 are connected by refrigerant piping. Also, the outdoor unit 5 includes an outdoor blower 55 for promoting heat exchange of a refrigerant. The outdoor unit 5 includes an outdoor unit control unit 57 that performs various controls of the air conditioner 1.

The indoor unit 2 is constituted by an indoor expansion valve 22, an indoor heat exchanger 21, a temperature sensor 25, an indoor blower 23, an indoor unit control unit 26, and a leak detector 24. The indoor heat exchanger 21 and the indoor expansion valve 22 are connected by refrigerant piping. Also, the indoor unit 2 is electrically connected to the leak detector 24. The outdoor expansion valve 51 and the indoor expansion valve 22 are connected by liquid refrigerant piping. A liquid refrigerant shutoff valve 61 is provided between the indoor expansion valve 22 and the outdoor expansion valve 51. Also, the indoor heat exchanger 21 and the four-way valve 53 are connected by gas refrigerant piping, and a gas refrigerant shutoff valve 62 is provided between the indoor heat exchanger 21 and the four-way valve 53.

The indoor unit 3 is constituted by an indoor expansion valve 32, an indoor heat exchanger 31, a temperature sensor 35, an indoor blower 33, an indoor unit control unit 36, and a leak detector 34. The indoor heat exchanger 31 and the indoor expansion valve 32 are connected by refrigerant piping. Also, the indoor unit 3 is electrically connected to the leak detector 34. The outdoor expansion valve 51 and the indoor expansion valve 32 are connected by liquid refrigerant piping. A liquid refrigerant shutoff valve 71 is provided between the indoor expansion valve 32 and the outdoor expansion valve 51. Also, the indoor heat exchanger 31 and the four-way valve 53 are connected by gas refrigerant piping, and a gas refrigerant shutoff valve 72 is provided between the indoor heat exchanger 31 and the four-way valve 53.

The indoor unit 4 is constituted by an indoor expansion valve 42, an indoor heat exchanger 41, a temperature sensor 45, an indoor blower 43, an indoor unit control unit 46, and a leak detector 44. The indoor heat exchanger 41 and the indoor expansion valve 42 are connected by refrigerant piping. Also, the indoor unit 4 is electrically connected to the leak detector 44. The outdoor expansion valve 51 and the indoor expansion valve 42 are connected by liquid refrigerant piping. A liquid refrigerant shutoff valve 81 is provided between the indoor expansion valve 42 and the outdoor expansion valve 51. Also, the indoor heat exchanger 41 and the four-way valve 53 are connected by gas refrigerant piping, and a gas refrigerant shutoff valve 82 is provided between the indoor 5 heat exchanger 41 and the four-way valve 53.

The outdoor unit control unit 57 is capable of communicating with the indoor unit control units 26, 36, and 47 described above. As for a communication method, a general-purpose protocol such as, for example, Modbus may be used. The liquid refrigerant shutoff valves 61, 71, and 81, and the gas refrigerant shutoff valves 62, 72, and 82 are opened and closed under the control of the outdoor unit control unit 57. Also, detection results of the leak detectors 24, 34, and 44 are notified to the outdoor unit control unit 57 via the indoor unit control units 26, 36, and 47.

Functions executed by the outdoor unit control unit 57 and the indoor unit control units 26, 36, and 47 are realized by, for example, a hardware processor such as a central processing unit (CPU) executing a program (software). Some or all of these components may be realized by hardware (circuit unit including a circuitry) such as a large scale integration (LSI), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), and a graphics processing unit (GPU), or may be realized by software and hardware in cooperation. The program may be stored in advance in a storage device (storage device including a non-transitory storage medium) such as a hard disk drive (HDD), a solid state drive (SSD), or a flash memory, or may be stored in a detachable storage medium (non-transitory storage medium) such as a DVD or a CD-ROM and installed by mounting the storage medium on a drive device. An operation unit that is not shown in the drawings and receives an operation by an inspector is provided in the outdoor unit control unit 57 and the indoor unit control units 26, 36, and 47.

In the configuration shown in FIG. 1, one leak detector is provided for each indoor unit, but it is not necessarily required for the indoor unit and the leak detector to be a one-to-one pair. Also, any of the liquid refrigerant shutoff valves 61, 71, and 81 and the gas refrigerant shutoff valves 62, 72, and 82 may be in a form of an electric valve whose opening is variable and capable of shutting off a flow of the refrigerant, or in a form of a solenoid valve that switches between an open state and a closed state.

As shown in FIG. 1 described above, the air conditioner 1 includes: the outdoor unit 2 that includes the outdoor expansion valve 51, the outdoor heat exchanger 52, the four-way valve 53, and the compressor 54; the indoor units 2, 3, and 4 that includes the indoor heat exchangers 21, 31, and 41, and the indoor expansion valves 22, 32, and 42 that adjust an amount of the refrigerant flowing through the indoor heat exchangers 21, 31, and 41; the shutoff unit that connects the outdoor unit 5 and the indoor units 2, 3, and 4 in parallel to the same refrigerant piping system, either singly or in a plurality of connections, and that incorporates a plurality of shutoff mechanisms (the liquid refrigerant shutoff valves 61, 71, and 81, and the gas refrigerant shutoff valves 62, 72, and 92) capable of shutting off a flow of the refrigerant between the outdoor unit 5 and the indoor units 2, 3, and 4; and the refrigerant leak detectors (leak detectors 24, 34, and 44) electrically connected to the indoor units 2, 3, and 4. There are three shutoff units corresponding to (the liquid refrigerant shutoff valve 61 and the gas refrigerant shutoff valve 62), (the liquid refrigerant shutoff valve 71 and the gas refrigerant shutoff valve 72), and (the liquid refrigerant shutoff valve 81 and the gas refrigerant shutoff valve 82).

FIG. 2 is a diagram showing a configuration of the leak detectors 24, 34, and 44. The leak detectors 24, 34, and 44 each include a simple inspection mode execution button 501, an alarm light emitting diode (LED) 502, an alarm buzzer 503, and a refrigerant leak sensor 504. The simple inspection mode execution button 501 is a button operated by the inspector or the like. It is constituted by a refrigerant leak sensor 504. The simple inspection mode execution button 501 is a button for checking whether or not the alarm LED 502 lights up and whether or not the alarm buzzer 503 activates an alarm. If there is a problem with the alarm LED 502, the alarm LED 502 will not emit light even if the simple inspection mode execution button 501 is operated. Similarly, if there is a problem with the alarm buzzer 503, the alarm buzzer 503 will not activate an alarm even if the simple inspection mode execution button 501 is operated.

The alarm LED 502 is an LED that lights up when a leak is detected by the refrigerant leak sensor 504 or when the simple inspection mode execution button 501 is operated. The alarm buzzer 503 is a buzzer that activates an alarm when a leak is detected by the refrigerant leak sensor 504 or when the simple inspection mode execution button 501 is operated. The refrigerant leak sensor 504 is a sensor for detecting a leak of the refrigerant in the indoor units 2, 3, and 4.

FIG. 3 is a flowchart showing a flow of processing executed by the outdoor unit control unit 57, the indoor unit control units 26, 36, and 47, and the leak detectors 24, 34, and 44. In FIG. 3, when the outdoor unit control unit 57 receives an operation to start an outdoor unit detailed inspection mode via the operation unit (step S101: YES), it determines whether or not the air conditioner 1 is in operation (step S102). If the air conditioner 1 is not in operation (step S102: NO), the processing proceeds to step S104. If the air conditioner 1 is in operation (step S102: YES), the outdoor unit control unit 57 stops the operation (step S103), and the processing proceeds to step S104.

The outdoor unit control unit 57 starts an inspection operation of the shutoff valves (the liquid refrigerant shutoff valves 61, 71, and 81 and the gas refrigerant shutoff valves 62, 72, and 82) (step S104). The inspection operation of the shutoff valves is an operation for confirming whether or not the piping is correctly connected by opening and closing the shutoff valves. Next, it is determined whether or not an operation to start the simple inspection mode of the leak detector has been received in any of the indoor unit control units 26, 36, and 47 (step S105).

The simple inspection mode is a mode in which the inspector operates the inspection mode execution button 501, confirms that the alarm LED 502 lights up and the alarm buzzer 503 activates an alarm, and inputs whether or not there is an abnormality in the alarm LED 502 and whether or not there is an abnormality in the alarm buzzer 503 into the indoor unit control unit.

Furthermore, when the indoor unit control unit 26 receives an operation to start the simple inspection mode, a target of the simple inspection mode is the leak detector 24. When the indoor unit control unit 36 receives an operation to start the simple inspection mode, a target of the simple inspection mode is the leak detector 34. When the indoor unit control unit 46 receives an operation to start the simple inspection mode, a target of the simple inspection mode is the leak detector 44.

If the operation to start the simple inspection mode has not been received (step S105: NO), the processing proceeds to step S109. When the operation to start the simple inspection mode has been received (step S105: YES), it is determined whether or not an input indicating no abnormality has been received for the alarm LED 502 (step S106). If an input indicating an abnormality is received (step S106: NO), the indoor unit control unit 26 confirms the abnormality (step S108), and the processing proceeds to step S109.

If an input indicating no abnormality is received (step S106: YES), the indoor unit control unit 26 determines whether or not an input indicating no abnormality has been received for the alarm buzzer 503 (step S107). If an input indicating an abnormality is received (step S107: NO), the indoor unit control unit 26 confirms the abnormality (step S108), and the processing proceeds to step S109.

If an input indicating no abnormality is received (step S106: YES), the outdoor unit control unit 57 determines whether or not an input indicating no abnormality of the shutoff valve has been received by the inspector (step S109). If an input indicating an abnormality is received (step S109: NO), the outdoor unit control unit 57 confirms the abnormality (step S110) and stops the operation (step S111). If an input indicating no abnormality is received (step S109: YES), the outdoor unit control unit 57 stops the operation as is (step S111).

As described above, the first embodiment has a simple inspection mode for confirming the refrigerant leak detection operation of the leak detector (24, 34, and 44) and a detailed inspection mode for confirming, by operating the compressor 54, that each of the plurality of shutoff mechanisms incorporated in the shutoff unit is operating normally, and the simple inspection mode and the detailed inspection mode can be selectively executed.

Then, when the simple inspection mode is performed in parallel while the detailed inspection mode is being performed, it is possible to reduce the time required to determine whether or not the shutoff valve and the refrigerant leak detector are operable. Also, when the detailed inspection mode is started by operating the outdoor unit and the simple inspection mode is started by operating the leak detector, it is possible to improve convenience for the inspector.

Second Embodiment

In a second embodiment, a form in which an inspection target unit to be inspected within one system is divided into two or more groups and inspected will be described. The grouping will be specifically described with reference to the drawings. FIG. 4 is a diagram showing an example of grouping. The configuration shown in FIG. 4 is the same as the configuration shown in FIG. 1, and therefore descriptions of respective portions will be omitted.

The grouping shown in FIG. 4 shows a form in which units are divided into two groups (Gr1 and Gr2). The inspection target unit described above is configured by an indoor unit, a liquid refrigerant shutoff valve, and a gas refrigerant shutoff valve. A configuration including these three is regarded as one inspection target unit. Then, in the present embodiment, grouping is performed such that there is at least one group including two or more inspection target units. Therefore, for example, if there are five inspection target units, grouping is conceivable that two groups each including two inspection target units and one group including a single inspection target unit, one group including two inspection target units and two groups each including a single inspection target unit, or one group including three inspection target units and one group including two inspection target units.

After the grouping is performed in advance in this manner, a unit inspection mode is performed to confirm that each of the plurality of shutoff mechanisms incorporated in the inspection target unit is operating normally. FIG. 5 is a flowchart showing a flow of the unit inspection mode. Furthermore, the processing shown in FIG. 5 is based on the grouping shown in FIG. 4.

In FIG. 5, when an outdoor unit control unit 57 receives an operation to start the unit inspection mode via the operation unit (step S201: YES), it determines whether or not an air conditioner 1 is in operation (step S202). If the air conditioner 1 is not in operation (step S202: NO), the processing proceeds to step S204. If the air conditioner 1 is in operation (step S202: YES), the outdoor unit control unit 57 stops the operation (step S203), and the processing proceeds to step S204.

The outdoor unit control unit 57 closes a liquid refrigerant shutoff valve 81 of Gr1 to be inspected (step S204), and starts the operation (step S205). At this time, shutoff valves of Gr2 (liquid refrigerant shutoff valves 61 and 71, and gas refrigerant shutoff valves 62 and 72) are open, and a cooling operation or heating operation is performed. Once the operation state has stabilized, the outdoor unit control unit 57 confirms that the liquid refrigerant shutoff valve 81 is closed using a temperature sensor 45 installed in an indoor heat exchanger 41 (step S206).

After confirming that the liquid refrigerant shutoff valve 81 is operating normally, the outdoor unit control unit 57 opens the liquid refrigerant shutoff valve 81 (step S207), closes a gas refrigerant shutoff valve 82 (step S208), and confirms that the gas refrigerant shutoff valve 82 is closed using the temperature sensor 45 (step S209). After confirming that the gas refrigerant shutoff valve 82 is operating normally, the outdoor unit control unit 57 opens the gas refrigerant shutoff valve 82 (step S210), and the processing proceeds to an inspection of Gr2.

During the inspection of Gr2, shutoff valves of Gr1 (the liquid refrigerant shutoff valve 81 and the gas refrigerant shutoff valve 82) are open, and an indoor unit 4 continues a cooling operation or heating operation. Once the operation state has stabilized, the outdoor unit control unit 57 closes the liquid refrigerant shutoff valves 61 and 71 (step S211) and confirms that the liquid refrigerant shutoff valves 61 and 71 are closed using temperature sensors 25 and 35 installed in indoor heat exchangers 21 and 31 (step S212). After confirming that the liquid refrigerant shutoff valves 61 and 71 are operating normally, the outdoor unit control unit 57 opens the liquid refrigerant shutoff valves 61 and 71 (step S213), closes the gas refrigerant shutoff valves 62 and 72 (step S214), and confirms that the gas refrigerant shutoff valves 62 and 72 are closed using the temperature sensors 25 and 35 (step S215). After confirming that the gas refrigerant shutoff valves 62 and 72 are operating normally, the outdoor unit control unit 57 opens the gas refrigerant shutoff valves 62 and 72 (step S216) and ends the unit inspection mode.

By grouping the inspection target units to be inspected in this manner, it is possible to reduce an inspection time.

The following will provide additional statements regarding the second embodiment.

Additional Statement 1

An air conditioner including:

• • an outdoor unit that includes an outdoor expansion valve, an outdoor heat exchanger, a four-way valve, and a compressor;
  • an indoor unit that includes an indoor heat exchanger and an indoor expansion valve that adjusts an amount of a refrigerant flowing through the indoor heat exchanger;
  • a shutoff unit that connects the outdoor unit and the indoor unit in parallel to the same refrigerant piping system, either singly or in a plurality of connections, and that incorporates a plurality of shutoff mechanisms capable of shutting off a flow of the refrigerant between the outdoor unit and the indoor unit;
  • a refrigerant leak detector electrically connected to the indoor unit; and
  • an inspection target unit having the shutoff unit and the indoor heat exchanger, in which
  • the shutoff unit is connected to the outdoor unit via at least one liquid pipe through which a liquid refrigerant flows and at least one gas pipe through which a gas refrigerant flows, and is connected to the indoor unit via at least one liquid pipe through which the liquid refrigerant flows and at least one gas pipe through which the gas refrigerant flows,
  • the air conditioner includes an inspection mode for confirming, by operating the compressor, that each of the plurality of shutoff mechanisms incorporated in the shutoff unit is operating normally, and
  • the inspection mode is executable by dividing the inspection target unit to be inspected within one system into two or more groups.

Additional Statement 2

The air conditioner according to additional statement 1, in which when the inspection mode is performed, a group not being inspected performs either a cooling operation, a heating operation, or a simultaneous cooling and heating operation.

Additional Statement 3

The air conditioner according to additional statement 1, in which the grouping divides the number of indoor units included in the inspection target unit into a substantially equal number of units.

Additional Statement 4

The air conditioner according to additional statement 1, in which the grouping is divided such that a total capacity of the indoor units to which the inspection target unit is connected is substantially equal.

Additional Statement 5

The air conditioner according to additional statement 1, in which a determination of normality of the inspection target unit is performed by an indoor unit temperature sensor downstream of the shutoff unit.

As described above, according to the present embodiment, it is possible to provide a technology capable of suppressing discomfort given to a subject.

While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.