Air conditioner

Abstract

The present application relates to an air conditioner capable of easily achieving energy saving. The air conditioner is provided with an indoor heat exchanger, an outdoor heat exchanger, a first pipe, a second pipe, a compressor, a four-way valve, an expansion valve, a first bypass pipe, a heat exchange portion, a first valve, and a second valve. The heat exchange portion exchanges heat between the first pipe between the outdoor heat exchanger and the suction port of the compressor and the second pipe between the outdoor heat exchanger and the expansion valve, and the first bypass pipe. The first valve and the second valve can adjust the amount of refrigerant flowing in the first bypass pipe.

Description

Technical Field

[0001] The embodiments of the present invention relate to an air conditioner. Background Technology

[0002] Air conditioners, like air conditioners, regulate indoor temperature by condensing and evaporating the refrigerant in a refrigeration cycle.

[0003] Patent Document 1: International Publication No. 2017-068649

[0004] In this type of air conditioner, it is more beneficial if energy saving can be easily achieved. Summary of the Invention

[0005] One example of the problem that this invention aims to solve is to obtain an air conditioner that is easy to achieve energy saving.

[0006] An air conditioner according to an embodiment of the present invention includes an indoor heat exchanger, an outdoor heat exchanger, a first piping, a second piping, a compressor, a four-way valve, an expansion valve, a first bypass piping, a heat exchange section, a first valve, a second valve, and a control device. The first piping connects the indoor heat exchanger and the outdoor heat exchanger, allowing refrigerant to flow. The second piping connects the outdoor heat exchanger and the indoor heat exchanger, allowing refrigerant to flow. The compressor is located on the first piping and has a refrigerant inlet and a refrigerant outlet. The four-way valve is located on the first piping and can change the direction of refrigerant flow. The expansion valve is located on the second piping. The first bypass piping has one end connected to the first piping between the indoor heat exchanger and the outlet, and another end connected to the second piping between the indoor heat exchanger and the expansion valve, allowing refrigerant to flow. The heat exchange section exchanges heat with at least one of the first piping between the outdoor heat exchanger and the suction inlet, and the second piping between the outdoor heat exchanger and the expansion valve, and with the first bypass piping. The first valve, located on the first bypass piping between one end and the heat exchange section, is capable of adjusting the amount of refrigerant flowing in the first bypass piping. The second valve, located on the first bypass piping between the other end and the heat exchange section, is also capable of adjusting the amount of refrigerant flowing in the first bypass piping. The control device controls the four-way valve, the expansion valve, the first valve, and the second valve.

[0007] In the aforementioned air conditioner, for example, the heat exchange section includes a first heat exchanger and a second heat exchanger. The first heat exchanger exchanges heat between the first piping and the first bypass piping between the outdoor heat exchanger and the suction inlet. The second heat exchanger exchanges heat between the second piping and the first bypass piping between the outdoor heat exchanger and the expansion valve. A first valve is provided on the first bypass piping between one end and the first heat exchanger. A second valve is provided on the first bypass piping between the other end and the second heat exchanger.

[0008] The aforementioned air conditioner includes, for example, a three-way valve, a second bypass pipe, and an on / off valve. The three-way valve is located on the first bypass pipe and can change the direction of refrigerant flow. The second bypass pipe is connected to the first pipe between the compressor and the four-way valve, as well as the three-way valve, allowing refrigerant flow. The on / off valve is located on the first pipe between one end and the four-way valve.

[0009] In the aforementioned air conditioner, for example, the first heat exchanger and the second heat exchanger are heat storage materials.

[0010] Based on the above air conditioners, it is possible to obtain an air conditioner that is easy to achieve energy saving. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the refrigerant system of an air conditioner during refrigeration operation, representing an embodiment of the invention.

[0012] Figure 2 This is a schematic diagram of the refrigerant system of an air conditioner during heating operation, representing an embodiment of the invention.

[0013] Figure 3 It is a block diagram that functionally represents the configuration of an air conditioner in an implementation method.

[0014] Figure 4 This is a flowchart illustrating an example of the cooling operation control of an air conditioner in an implementation method.

[0015] Figure 5 This is a flowchart illustrating an example of the heating operation control of an air conditioner in an implementation method.

[0016] Figure 6 This is a schematic diagram of the refrigerant system of an air conditioner during dehumidification operation in an embodiment.

[0017] Figure 7 This is a block diagram illustrating an example of the hardware configuration of the control device in an implementation method.

[0018] Explanation of symbols

[0019] 10: Air conditioner; 14: Control device; 21: Outdoor heat exchanger; 23: Compressor; 23a: Inlet; 23b: Outlet; 25: Four-way valve; 31: First expansion valve; 32: Second expansion valve (first valve); 33: Third expansion valve (second valve); 41: Indoor heat exchanger; 45: Heat exchange section; 51: First piping; 52: Second piping; 53: First bypass piping; 53a: One end; 53b: The other end; 54: Second bypass piping; 62: First heat exchanger; 63: Second heat exchanger. Detailed Implementation

[0020] The following is for reference Figures 1 to 7 One embodiment will be described. Furthermore, in this specification, the constituent elements of an embodiment and their descriptions are sometimes described in various ways. The constituent elements and their descriptions are merely examples and are not limited to the representations in this specification. Constituent elements may also be identified by names different from those used in this specification. Moreover, constituent elements may also be described in representations different from those used in this specification.

[0021] Figure 1 This is a schematic diagram of the refrigerant system of the air conditioner 10 during cooling operation according to this embodiment. The air conditioner 10 is, for example, a household air conditioner. However, the air conditioner 10 is not limited to this example and may also be other air conditioners such as those used in offices.

[0022] like Figure 1 As shown, the air conditioner 10 includes an outdoor unit 11, an indoor unit 12, refrigerant piping 13, and a control device 14. The outdoor unit 11 is, for example, located outdoors. The indoor unit 12 is, for example, located indoors.

[0023] The air conditioner 10 has a refrigeration cycle consisting of an outdoor unit 11 and an indoor unit 12 connected by a refrigerant piping 13. Refrigerant flows between the outdoor unit 11 and the indoor unit 12 through the refrigerant piping 13. Furthermore, the outdoor unit 11 and the indoor unit 12 are electrically connected to each other, for example, through electrical wiring.

[0024] The outdoor unit 11 includes an outdoor heat exchanger 21, an outdoor fan 22, a compressor 23, a liquid receiver 24, a four-way valve 25, a first expansion valve 31, a second expansion valve 32, a third expansion valve 33, a three-way valve 34, and an on / off valve 35. The indoor unit 12 includes an indoor heat exchanger 41 and an indoor fan 42.

[0025] The refrigerant piping 13 is made of a metal such as copper or aluminum. The refrigerant piping 13 includes a first piping 51, a second piping 52, a first bypass piping 53, and a second bypass piping 54. The first piping 51 connects the indoor heat exchanger 41 to the outdoor heat exchanger 21. A compressor 23, a receiver 24, a four-way valve 25, a three-way valve 34, and an on / off valve 35 are located on the first piping 51. The second piping 52 connects the outdoor heat exchanger 21 to the indoor heat exchanger 41. A first expansion valve 31 is located on the second piping 52. The first bypass piping 53 is connected to both the first piping 51 and the second piping 52. A second expansion valve 32, a third expansion valve 33, and a three-way valve 34 are located on the first bypass piping 53. The second bypass piping 54 is connected to both the first piping 51 and the first bypass piping 53.

[0026] During refrigeration operation, refrigerant flows from the indoor heat exchanger 41 to the outdoor heat exchanger 21 through the first piping 51, and from the outdoor heat exchanger 21 to the indoor heat exchanger 41 through the second piping 52. During refrigeration operation, the on / off valve 35 is in the open state. During refrigeration operation, when the second expansion valve 32 and the third expansion valve 33 are open, a portion of the refrigerant flows in the first bypass piping 53. Figure 1 The arrow represents an example of refrigerant flow during refrigeration operation.

[0027] Figure 2 This is a schematic diagram of the refrigerant system of the air conditioner 10 during heating operation in this embodiment. (Example) Figure 2 As shown, during heating operation, refrigerant flows from the outdoor heat exchanger 21 to the indoor heat exchanger 41 through the first piping 51, and from the indoor heat exchanger 41 to the outdoor heat exchanger 21 through the second piping 52. During heating operation, the on / off valve 35 is in the open state. During heating operation, when the second expansion valve 32 and the third expansion valve 33 are open, a portion of the refrigerant flows in the first bypass piping 53. Figure 2 The arrow represents an example of refrigerant flow during heating operation.

[0028] The outdoor heat exchanger 21 of the outdoor unit 11 acts as an evaporator to absorb heat from the refrigerant, or as a condenser to dissipate heat from the refrigerant, depending on the direction of refrigerant flow. The outdoor fan 22 directs airflow towards the outdoor heat exchanger 21, promoting heat exchange between the refrigerant and the air within the outdoor heat exchanger 21. In other words, the outdoor fan 22 generates airflow that exchanges heat with the outdoor heat exchanger 21.

[0029] The compressor 23 has a suction port 23a and a discharge port 23b. The compressor 23 draws in refrigerant through the suction port 23a and discharges the compressed refrigerant through the discharge port 23b. Thus, the compressor 23 compresses the refrigerant in the refrigeration cycle and generates a refrigerant cycle.

[0030] The receiver 24 is connected to the suction port 23a of the compressor 23. The receiver 24 separates the gaseous refrigerant from the liquid refrigerant. Therefore, the compressor 23 can draw in the gaseous refrigerant that has passed through the receiver 24 through the suction port 23a. The receiver 24 is integrally formed with the compressor 23, thus serving as the suction port of the compressor 23.

[0031] The four-way valve 25 is connected to the outdoor heat exchanger 21, the indoor heat exchanger 41, the outlet 23b of the compressor 23, and the receiver 24 (the suction port 23a of the compressor 23). During heating and cooling operation, the four-way valve 25 switches the flow paths connected to the outdoor heat exchanger 21, the indoor heat exchanger 41, the outlet 23b of the compressor 23, and the receiver 24, respectively, changing the direction of refrigerant flow. The four-way valve 25 is also known as a switching valve.

[0032] like Figure 1 As shown, during cooling operation, the four-way valve 25 connects the outdoor heat exchanger 21 to the outlet 23b of the compressor 23. Furthermore, during cooling operation, the four-way valve 25 connects the indoor heat exchanger 41 to the receiver 24. Thus, the refrigerant compressed by the compressor 23 flows to the outdoor heat exchanger 21, and the refrigerant evaporated in the indoor heat exchanger 41 flows to the receiver 24.

[0033] like Figure 2 As shown, during heating operation, the four-way valve 25 connects the outdoor heat exchanger 21 to the receiver 24. Furthermore, during heating operation, the four-way valve 25 connects the indoor heat exchanger 41 to the outlet 23b of the compressor 23. Thus, the refrigerant compressed by the compressor 23 flows to the indoor heat exchanger 41, and the refrigerant evaporated in the outdoor heat exchanger 21 flows to the receiver 24.

[0034] Expansion valves 31, 32, and 33 are, for example, electromagnetic expansion valves. Alternatively, they can be other types of expansion valves. The amount of refrigerant passing through them is adjusted by controlling their opening degree. Expansion valve 32 is an example of valve 1, and expansion valve 33 is an example of valve 2.

[0035] The indoor heat exchanger 41 of the indoor unit 12 absorbs heat as an evaporator or dissipates heat as a condenser, depending on the direction of refrigerant flow. The indoor fan 42 blows air towards the indoor heat exchanger 41, promoting heat exchange between the indoor heat exchanger 41 and the air. In other words, the indoor fan 42 generates airflow that exchanges heat with the indoor heat exchanger 41.

[0036] In the air conditioner 10 with the various elements configured as described above, the first piping 51 has zones 51a, 51b, 51c, and 51d. Zone 51a is a portion of the first piping 51 between the indoor heat exchanger 41 and the four-way valve 25. Zone 51b is a portion of the first piping 51 between the four-way valve 25 and the liquid receiver 24. Zone 51c is a portion of the first piping 51 between the discharge port 23b of the compressor 23 and the four-way valve 25. Zone 51d is a portion of the first piping 51 between the four-way valve 25 and the outdoor heat exchanger 21.

[0037] The second piping 52 has regions 52a and 52b. Region 52a is a part of the second piping 52 between the outdoor heat exchanger 21 and the first expansion valve 31. Region 52b is a part of the second piping 52 between the first expansion valve 31 and the indoor heat exchanger 41.

[0038] The first bypass pipe 53 has one end 53a and another end 53b. One end 53a is connected to the first pipe 51 between the indoor heat exchanger 41 and the outlet 23b. That is, one end 53a is located in region 51a of the first pipe 51. The other end 53b is connected to the second pipe 52 between the indoor heat exchanger 41 and the first expansion valve 31. That is, the other end 53b is located in region 52b of the second pipe 52.

[0039] A second expansion valve 32, a three-way valve 34, and a third expansion valve 33 are provided on the first bypass pipe 53. The second expansion valve 32 is located near one end 53a. The three-way valve 34 is located on the other end 53b relative to the second expansion valve 32. The third expansion valve 33 is located on the other end 53b relative to the three-way valve 34. The third expansion valve 33 is located near the other end 53b.

[0040] The second bypass pipe 54 has one end 54a and another end 54b. One end 54a is connected to the first pipe 51 between the inlet 23a and the four-way valve 25. That is, one end 54a is located in region 51b of the first pipe 51. The other end 54b is connected to the three-way valve 34. That is, the other end 54b is located in the three-way valve 34.

[0041] The three-way valve 34 switches the flow paths connected to the portion between one end 53a of the first bypass pipe 53 and the three-way valve 34, the portion between the other end 53b of the first bypass pipe 53 and the three-way valve 34, and the second bypass pipe 54, thereby changing the direction of refrigerant flow. This three-way valve 34 allows refrigerant to flow between the portion between the other end 53b of the first bypass pipe 53 and the three-way valve 34 and the region 51b of the first pipe 51. The three-way valve 34 is also called a switching valve.

[0042] The on / off valve 35 is located in region 51a of the first piping 51. When the valve is open, the on / off valve 35 allows refrigerant to flow in region 51a; when the valve is closed, it cuts off the flow of refrigerant in region 51a.

[0043] Furthermore, the outdoor unit 11 of this embodiment includes a heat exchange section 45. The heat exchange section 45 includes a first heat exchanger 62 and a second heat exchanger 63.

[0044] The first heat exchanger 62 and the second heat exchanger 63 are, for example, heat storage materials. The heat storage material is a latent heat storage material filled in a block-shaped container. For example, the latent heat storage material is calcium chloride. The first heat exchanger 62 and the second heat exchanger 63 may also have other latent heat storage materials. In this embodiment, the first heat exchanger 62 and the second heat exchanger 63 are, for example, heat storage materials that can be used in a temperature range of about 10°C to about 100°C.

[0045] The first heat exchanger 62 and the second heat exchanger 63 are not limited to the examples described above. For example, they may be other heat storage materials such as sensible heat storage materials, or heat storage materials that can be used in other temperature zones. Furthermore, the first heat exchanger 62 and the second heat exchanger 63 may be made of different heat storage materials.

[0046] The region 51d of the first piping 51 between the first heat exchanger 62 and the outdoor heat exchanger 21 and the suction inlet 23a, as well as the first bypass piping 53, are thermally connected. For example, the region 51d of the first piping 51 and the first bypass piping 53 are separated from each other and pass through the first heat exchanger 62.

[0047] The first heat exchanger 62 configured in this way performs heat exchange between region 51d of the first piping 51 and the first bypass piping 53. That is, in the first heat exchanger 62, heat exchange occurs between the refrigerant in region 51d of the first piping 51 and the refrigerant in the first bypass piping 53.

[0048] Compared to zone 51d and the first bypass pipe 53, the first heat exchanger 62 can store a larger amount of heat (heat storage capacity). Furthermore, zone 51d and the first bypass pipe 53 are made of metal and are in close contact with the latent heat storage material of the first heat exchanger 62. Therefore, heat conduction is easily achieved between zone 51d and the first bypass pipe 53 and the latent heat storage material of the first heat exchanger 62.

[0049] The second heat exchanger 63 is thermally connected to region 52a of the second piping 52 between the outdoor heat exchanger 21 and the first expansion valve 31, and to the first bypass piping 53. For example, region 52a and the first bypass piping 53 are separate from each other and pass through the second heat exchanger 63. Therefore, the second heat exchanger 63 thermally connects region 52a and the first bypass piping 53. This configuration of the second heat exchanger 63 allows heat exchange between region 52a of the second piping 52 and the first bypass piping 53. That is, in the second heat exchanger 63, heat exchange occurs between the refrigerant in region 52a and the refrigerant in the first bypass piping 53.

[0050] Compared to the first bypass piping 53 and zone 52b, the second heat exchanger 63 has a larger heat storage capacity. Furthermore, the first bypass piping 53 and zone 52a are made of metal and are in close contact with the latent heat storage material of the second heat exchanger 63. Therefore, heat conduction is easily achieved between the first bypass piping 53 and zone 52a and the latent heat storage material of the second heat exchanger 63.

[0051] In addition, the air conditioner 10 also has temperature sensors 71A to 71J and a human body sensor 72.

[0052] Temperature sensor 71A is disposed, for example, in the housing of outdoor unit 11. Temperature sensor 71A detects the outside air temperature of the outdoor environment in which outdoor unit 11 is located.

[0053] Temperature sensor 71B is disposed on outdoor heat exchanger 21. Temperature sensor 71B detects the temperature of the refrigerant flowing in outdoor heat exchanger 21. For example, temperature sensor 71B is configured at a location where the saturation temperature of the refrigerant flowing in outdoor heat exchanger 21 can be obtained.

[0054] Temperature sensor 71C is disposed, for example, in the housing of indoor unit 12. Temperature sensor 71C detects the indoor temperature (room temperature) of the room in which indoor unit 12 is configured.

[0055] Temperature sensor 71D is disposed in the indoor unit 12 on the side of the four-way valve 25 relative to the indoor heat exchanger 41, and detects the temperature of the refrigerant located on the side of the four-way valve 25 relative to the indoor heat exchanger 41. Temperature sensor 71E is disposed in the indoor heat exchanger 41. Temperature sensor 71E detects the temperature of the refrigerant flowing in the indoor heat exchanger 41. Temperature sensor 71F is disposed in the indoor unit 12 on the side of the first expansion valve 31 relative to the indoor heat exchanger 41, and detects the temperature of the refrigerant located on the side of the first expansion valve 31 relative to the indoor heat exchanger 41. For example, temperature sensors 71D to 71F are disposed at positions where the saturation temperature of the refrigerant can be obtained.

[0056] Temperature sensor 71G is located in the first heat exchanger 62. Temperature sensor 71G detects the temperature of the first heat exchanger 62.

[0057] Temperature sensor 71H is located in the second heat exchanger 63. Temperature sensor 71H detects the temperature of the second heat exchanger 63.

[0058] Temperature sensor 71I is located near the receiver 24 in region 51b of the first piping 51. Temperature sensor 71H detects the temperature of the refrigerant flowing in region 51b near the receiver 24.

[0059] Temperature sensor 71J is disposed in region 52a of the second piping 52 between the second heat exchanger 63 and the first expansion valve 31. Temperature sensor 71J detects the temperature of the refrigerant flowing in region 52a near the second heat exchanger 63.

[0060] A human body sensor 72 is installed in the indoor unit 12. The human body sensor 72 detects people (or animals) in the room where the indoor unit 12 is located. The human body sensor 72 is also called a human detection sensor.

[0061] The control device 14 may include, for example, an outdoor control device 14a and an indoor control device 14b. The outdoor control device 14a and the indoor control device 14b are electrically connected to each other via electrical wiring. At least one of the outdoor control device 14a and the indoor control device 14b may be, for example, a computer having a control device such as a CPU (Central Processing Unit) or a microcontroller, or a storage device such as ROM (Read Only Memory), RAM (Random Access Memory), or flash memory. However, the control device 14 is not limited to this example. For instance, the control device 14 may also have only one of the outdoor control device 14a and the indoor control device 14b.

[0062] The outdoor control device 14a controls the outdoor air supply fan 22, compressor 23, four-way valve 25, first expansion valve 31, second expansion valve 32, third expansion valve 33, three-way valve 34, and on / off valve 35 of the outdoor unit 11. The indoor control device 14b controls the indoor air supply fan 42 of the indoor unit 12.

[0063] The control device 14 controls the outdoor unit 11 and the indoor unit 12, thereby enabling the air conditioner 10 to perform cooling, heating, dehumidifying, and other operations. The indoor control device 14b can input signals from a remote control or from an information terminal such as a smartphone via a communication device.

[0064] Figure 3This is a block diagram that functionally represents the configuration of the air conditioner 10 according to this embodiment. For example... Figure 3 As shown, the air conditioner 10 of this embodiment also includes an outdoor fan drive circuit 81, an indoor fan drive circuit 82, an inverter circuit 83, a four-way valve drive circuit 84, a first expansion valve drive circuit 85, a second expansion valve drive circuit 86, a third expansion valve drive circuit 87, a three-way valve drive circuit 88, and an on / off valve drive circuit 89.

[0065] The outdoor fan drive circuit 81 drives the outdoor air supply fan 22. The indoor fan drive circuit 82 drives the indoor air supply fan 42. The inverter circuit 83 performs inverter control on the compressor 23, changing the frequency of the compressor 23. The inverter circuit 83 is, for example, a PAM (Pulse Amplitude Modulation) inverter circuit. However, the inverter circuit 83 is not limited to this example.

[0066] The four-way valve drive circuit 84 is the drive circuit for the four-way valve 25. The first expansion valve drive circuit 85 is the drive circuit for the first expansion valve 31. The second expansion valve drive circuit 86 is the drive circuit for the second expansion valve 32. The third expansion valve drive circuit 87 is the drive circuit for the third expansion valve 33. The three-way valve drive circuit 88 is the drive circuit for the three-way valve 34. The on / off valve drive circuit 89 is the drive circuit for the on / off valve 35.

[0067] The control device 14 is connected to temperature sensors 71A-71J, a human body sensor 72, an outdoor fan drive circuit 81, an indoor fan drive circuit 82, an inverter circuit 83, a four-way valve drive circuit 84, a first expansion valve drive circuit 85, a second expansion valve drive circuit 86, a third expansion valve drive circuit 87, a three-way valve drive circuit 88, and an on / off valve drive circuit 89. The control device 14 includes a temperature acquisition unit 91, an operation switching unit 92, an outdoor fan control unit 93, an indoor fan control unit 94, a compressor control unit 95, and a valve control unit 96.

[0068] The temperature acquisition unit 91 uses temperature sensors 71A to 72J to acquire the outside air temperature, the refrigerant temperature, the temperature of the first heat exchanger 62, and the temperature of the second heat exchanger 63. For example, the temperature acquisition unit 91 calculates the outside air temperature, the refrigerant temperature, the temperature of the first heat exchanger 62, and the temperature of the second heat exchanger 63 based on the output signals of the temperature sensors 71A to 71J.

[0069] The operation switching unit 92 switches the air conditioner 10 between cooling, heating, and dehumidifying operations. Additionally, the operation switching unit 92 can also switch the air conditioner 10 to other operating modes. A human body sensor 72 is connected to the operation switching unit 92.

[0070] The outdoor fan control unit 93 controls the outdoor air supply fan 22. For example, the outdoor fan control unit 93 controls the outdoor fan drive circuit 81, thereby controlling the speed of the motor of the outdoor air supply fan 22.

[0071] The indoor fan control unit 94 controls the indoor air supply fan 42. For example, the indoor fan control unit 94 controls the indoor fan drive circuit 82, thereby controlling the speed of the motor of the indoor air supply fan 42.

[0072] The compressor control unit 95 controls the compressor 23. For example, the compressor control unit 95 controls the inverter circuit 83, thereby controlling the frequency (operating frequency) of the compressor 23 by means of inverter control.

[0073] The valve control unit 96 controls the four-way valve 25, the first expansion valve 31, the second expansion valve 32, the third expansion valve 33, the three-way valve 34, and the on / off valve 35. The valve control unit 96 controls the four-way valve drive circuit 84, thereby driving the actuator of the four-way valve 25 to change the direction of refrigerant flow. The valve control unit 96 controls the first expansion valve drive circuit 85, the second expansion valve drive circuit 86, and the third expansion valve drive circuit 87, thereby changing the opening degree of the first expansion valve 31, the second expansion valve 32, and the third expansion valve 33. The valve control unit 96 controls the three-way valve drive circuit 88, thereby changing the direction of refrigerant flow in the three-way valve 34. The valve control unit 96 controls the on / off valve drive circuit 89, thereby changing the state (open state, closed state) of the on / off valve 35.

[0074] The following describes the cooling operation, heating operation, and dehumidification operation of the air conditioner 10 according to this embodiment. However, the air conditioner 10 is not limited to cooling operation, heating operation, and dehumidification operation; it can also perform other operations such as dehumidification operation and defrosting operation. Furthermore, the cooling operation, dehumidification operation, and heating operation of the air conditioner 10 are not limited to the examples described below.

[0075] Figure 4 This is a flowchart illustrating an example of the cooling operation control of the air conditioner 10 according to this embodiment. Additionally, for example, when the air conditioner 10 is started and the cooling operation begins simultaneously, the outdoor fan 22, compressor 23, and indoor fan 42 are stopped. In this case, the outdoor fan control unit 93, indoor fan control unit 94, and compressor control unit 95 start the outdoor fan 22, compressor 23, and indoor fan 42 at the start of the cooling operation.

[0076] During cooling operation, the outdoor fan control unit 93 adjusts the speed of the outdoor air supply fan 22. The indoor fan control unit 94 adjusts the speed of the indoor air supply fan 42. The compressor control unit 95 adjusts the operating frequency of the compressor 23. For example, the indoor fan control unit 94 controls the indoor air supply fan 42 between low-speed and high-speed operation based on the indoor temperature of the room where the indoor unit 12 is located or a signal input from the remote control.

[0077] like Figure 4 As shown, when refrigeration operation begins, the valve control unit 96 controls the four-way valve drive circuit 84 and the three-way valve drive circuit 88, causing the four-way valve 25 and the three-way valve 34 to change the direction of refrigerant flow (S501). Furthermore, at this time, the valve control unit 96 sets the on / off valve 35 to the open state. As a result, the outdoor heat exchanger 21 is connected to the discharge port 23b of the compressor 23, and the indoor heat exchanger 41 is connected to the receiver 24 (the suction port 23a of the compressor 23). That is, the control device 14 performs refrigeration operation by controlling the four-way valve 25 to allow refrigerant to flow from the discharge port 23b of the compressor 23 to the outdoor heat exchanger 21. Then, the valve control unit 96 opens the second expansion valve 32 and the third expansion valve 33. As a result, area 51a of the first piping 51 and area 52b of the second piping 52 are connected via the first bypass piping 53. In this case, no refrigerant flows in the second bypass piping 54.

[0078] Next, the operation switching unit 92 determines whether to end the cooling operation (S502). For example, if a stop signal or a switching signal to another operation is input from the remote control to the air conditioner 10, the operation switching unit 92 determines that the cooling operation has ended (S502: "Yes") and ends the cooling operation.

[0079] If the refrigeration operation has not ended (S502: "No"), the valve control unit 96 determines whether the return superheat (Su-Th2) is 3°C (S503). Temperature Su is the temperature detected by temperature sensor 71I, and temperature Th2 is the temperature detected by temperature sensor 71G.

[0080] If the return superheat (Su-Th2) is not 3°C ​​(S503: "No"), the valve control unit 96 controls the second expansion valve drive circuit 86 and the third expansion valve drive circuit 87 to adjust the opening degree of the second expansion valve 32 and the third expansion valve 33 (S504). The valve control unit 96 adjusts the opening degree of the second expansion valve 32 and the third expansion valve 33 to make the return superheat (Su-Th2) 3°C. If the return superheat (Su-Th2) is 3°C in S503 (S503: "Yes"), S504 is omitted.

[0081] Next, the valve control unit 96 determines whether the supercooling (Tc1-Tc) is above 6°C (S505). Temperature Tc1 is the temperature detected by temperature sensor 71H, and temperature Tc is the temperature detected by temperature sensor 71B.

[0082] If the supercooling (Tc1-Tc) is above 6°C (S505: "Yes"), the outdoor fan control unit 93 controls the outdoor fan drive circuit 81 to stop the outdoor air supply fan 22 (S506). This is because the refrigerant in the outdoor heat exchanger 21 is overcooled. If the supercooling (Tc1-Tc) is not less than 6°C (S507: "No"), the outdoor air supply fan 22 continues to be stopped (S506).

[0083] If the temperature drops below 6°C due to the shutdown of the outdoor fan 22 and the overcooling (Tc1-Tc) becomes less than 6°C (S507: "Yes"), the outdoor fan control unit 93 controls the outdoor fan drive circuit 81 to start (restart) the air supply of the outdoor fan 22 (S508). If the temperature drops below 6°C due to the overcooling (Tc1-Tc) in S505 (S505: "No"), S506 to S508 are omitted.

[0084] Repeat steps S502 to S508 until the refrigeration operation ends.

[0085] like Figure 1 As shown, during refrigeration operation, the high-temperature, high-pressure gaseous refrigerant discharged from the outlet 23b of the compressor 23 dissipates heat in the outdoor heat exchanger 21 through the four-way valve 25 and the first heat exchanger 62. The medium-temperature, medium-pressure liquid refrigerant, condensed in the outdoor heat exchanger 21, is depressurized in the first expansion valve 31 through the second heat exchanger 63. At this time, the refrigerant dissipates heat in both the first heat exchanger 62 and the second heat exchanger 63. The dissipated heat is transferred to both the first heat exchanger 62 and the second heat exchanger 63.

[0086] A portion of the low-temperature, low-pressure liquid refrigerant, after being depressurized in the first expansion valve 31, absorbs heat in the indoor heat exchanger 41. The gaseous refrigerant, after evaporating in the indoor heat exchanger 41, returns to the suction port 23a of the compressor 23 via the on / off valve 35 and the four-way valve 25. Furthermore, a portion of the low-temperature, low-pressure liquid refrigerant, after being depressurized in the first expansion valve 31, flows from the other end 53b of the first bypass pipe 53 to the first bypass pipe 53. The refrigerant flowing in the first bypass pipe 53 flows from one end 53a of the first bypass pipe 53 to the first pipe 51 via the third expansion valve 33, the three-way valve 34, the second heat exchanger 63, the first heat exchanger 62, and the second expansion valve 32. At this time, the refrigerant absorbs heat in the first heat exchanger 62 and the second heat exchanger 63, respectively. That is, the refrigerant flowing through the first bypass pipe 53, the refrigerant flowing in region 52a of the second pipe 52, and the refrigerant flowing in region 51d of the first pipe 51 exchange heat via the second heat exchanger 63 and the first heat exchanger 62, respectively. As a result, the refrigerant flowing through the first bypass pipe 53 is heated and vaporized. The refrigerant flowing in the first pipe 51 returns to the suction port 23a of the compressor 23 via the on / off valve 35 and the four-way valve 25.

[0087] Furthermore, when the outdoor fan 22 stops blowing air in S506 above, the amount of heat exchanged by the refrigerant in the outdoor heat exchanger 21 decreases, and the amount of vaporization decreases, but the heat storage capacity of at least the second heat exchanger 63 increases accordingly. Therefore, the refrigerant is further vaporized as it flows in the first bypass pipe 53. In addition, in this case, the outdoor fan 22 does not consume electricity, thus achieving energy saving in the air conditioner 10.

[0088] Furthermore, the capacity of the air conditioner 10 can also be set according to the corresponding superheat (Te1-Te). In addition, in the above-described cooling operation control, for example, when operating at the lowest capacity (minimum capacity) within the specified capacity range of the air conditioner 10, the SHF is set to 0.65, and the airflow (speed) of the indoor fan 42 is set to a constant airflow. Thus, the capacity of the air conditioner 10 is maintained at the lowest capacity within the specified capacity range, and is suppressed from reaching a high capacity. Here, when the airflow of the indoor fan 42 is increased, the SHF approaches 1. Furthermore, this facilitates the control of the second expansion valve 32 and the third expansion valve 33 when the air conditioner 10 operates at low capacity.

[0089] Figure 5This is a flowchart illustrating an example of the heating operation control of the air conditioner 10 according to this embodiment. Furthermore, for example, when the air conditioner 10 is started and heating operation begins simultaneously, the outdoor fan 22, compressor 23, and indoor fan 42 are stopped. In this case, the outdoor fan control unit 93, indoor fan control unit 94, and compressor control unit 95 start the outdoor fan 22, compressor 23, and indoor fan 42 at the start of heating operation. During low-capacity heating operation, for example, the operating frequency of compressor 23 is obtained by adding a predetermined value (e.g., 5Hz) to the minimum frequency of compressor 23. Therefore, during low-capacity operation, repeated starting and stopping of compressor 23 can be suppressed. That is, continuous operation of compressor 23 can be achieved.

[0090] like Figure 5 As shown, when heating operation begins, the valve control unit 96 controls the four-way valve drive circuit 84 and the three-way valve drive circuit 88, causing the four-way valve 25 and the three-way valve 34 to change the direction of refrigerant flow (S601). At this time, the valve control unit 96 sets the on / off valve 35 to the open state. Thus, the indoor heat exchanger 41 is connected to the discharge port 23b of the compressor 23, and the outdoor heat exchanger 21 is connected to the receiver 24 (the suction port 23a of the compressor 23). That is, the control device 14 executes heating operation by controlling the four-way valve 25 to allow refrigerant to flow from the discharge port 23b of the compressor 23 to the indoor heat exchanger 41 through the on / off valve 35. Furthermore, the four-way valve 25 is connected to the suction port 23a of the compressor 23 via area 51b of the first piping 51. Additionally, at this time, the second expansion valve 32 and the third expansion valve 33 are in the closed state. Furthermore, when the second expansion valve 32 and the third expansion valve 33 are in the open state, the three-way valve 34 is controlled such that a portion of the refrigerant flowing through the on / off valve 35 flows from region 51a of the first piping 51 into region 52b of the second piping 52 through the first bypass piping 53.

[0091] Next, the operation switching unit 92 determines whether to end the heating operation (S602). For example, if a stop signal or a switching signal to other operations is input from the remote control to the air conditioner 10, the operation switching unit 92 determines that the heating operation has ended (S602: "Yes") and ends the heating operation.

[0092] If the heating operation has not ended (S602: "No"), the valve control unit 96 determines whether the subcooling degree (Te2-Te) is above 7°C (S603). Temperature Te2 is the temperature detected by temperature sensor 71F, and temperature Te is the temperature detected by temperature sensor 71E.

[0093] If the subcooling degree (Te2-Te) is not above 7°C (S603: "No"), the valve control unit 96 returns to S602. If the subcooling degree (Te2-Te) is above 7°C (S603: "Yes"), since there is a possibility of so-called overcharging of liquid refrigerant accumulating in the indoor heat exchanger 41, the valve control unit 96 opens the second expansion valve 32 and the third expansion valve 33 (S604). As a result, refrigerant flows in the first bypass pipe 53, and the amount of refrigerant flowing into the indoor heat exchanger 41 is correspondingly reduced, thus eliminating the overcharging of the indoor heat exchanger 41.

[0094] The valve control unit 96 determines whether the subcooling degree (Te2-Te) is less than 7°C (S605). If the subcooling degree (Te2-Te) is not less than 7°C (S605: "No"), the second expansion valve 32 and the third expansion valve 33 are kept open (S604). If the subcooling degree (Te2-Te) is less than 7°C (S605: "Yes"), the valve control unit 96 closes the second expansion valve 32 and the third expansion valve 33 (S606). As a result, refrigerant stops flowing in the first bypass pipe 53.

[0095] like Figure 2 As shown, during heating operation, when the second expansion valve 32 and the third expansion valve 33 are open, the refrigerant flows as follows: A portion of the high-temperature, high-pressure gaseous refrigerant discharged from the outlet 23b of the compressor 23 flows to the outdoor heat exchanger 21 via the indoor heat exchanger 41, the first expansion valve 31, and the first heat exchanger 62. A portion of the high-temperature, high-pressure gaseous refrigerant discharged from the outlet 23b of the compressor 23 flows from one end 53a of the first bypass pipe 53 through the first bypass pipe 53, and from the other end 53b of the first bypass pipe 53 to the region 52b of the second pipe 52. In the first bypass pipe 53, the refrigerant passes through the second expansion valve 32, the first heat exchanger 62, the second heat exchanger 63, the three-way valve 34, and the third expansion valve 33. At this time, the refrigerant dissipates heat in the first heat exchanger 62 and the second heat exchanger 63. The heat dissipated is transferred to the first heat exchanger 62 and the second heat exchanger 63.

[0096] The refrigerant flowing in the second piping 52 passes through the first expansion valve 31 and the second heat exchanger 63 and then flows into the outdoor heat exchanger 21. The refrigerant flowing out of the outdoor heat exchanger 21 returns to the compressor 23 in the first piping 51 via the first heat exchanger 62 and the four-way valve 25. The refrigerant absorbs heat when passing through the second heat exchanger 63 in the second piping 52 and the first heat exchanger 61 in the first piping 51. That is, the refrigerant flowing in region 52a of the second piping 52 exchanges heat with the refrigerant flowing in the first bypass piping 53 via the second heat exchanger 63. Furthermore, the refrigerant flowing in region 51d of the first piping 51 exchanges heat with the refrigerant flowing in the first bypass piping 53 via the first heat exchanger 62. Therefore, the refrigerant flowing in region 52a of the second pipe 52 and the refrigerant flowing in region 51d of the first pipe 51 are heated, their pressure increases, and they are vaporized, returning to the compressor 23. At this time, the specific volume of the refrigerant increases. Thus, the refrigerant, in its pressurized and vaporized state, returns to the compressor 23, thereby suppressing the increase in electrical power consumption at the lowest frequency of 5Hz for the compressor 23.

[0097] Furthermore, in this embodiment, during heating operation, for example, each component is controlled to ensure that the evaporation temperature of the refrigerant in the outdoor heat exchanger 21 is 2°C lower than the outside air temperature. Additionally, the third expansion valve 33 is controlled to set the return superheat (Su-Th2) to 2°C.

[0098] Furthermore, during heating operation, the operation switching unit 92 can, for example, learn the user's tendency to start the heating operation using artificial intelligence. Also, the operation switching unit 92 can open the second expansion valve 32 and the third expansion valve 33 to start the heating operation before the predetermined start time (e.g., 1 hour) learned from the start of the heating operation, thus storing heat in the first heat exchanger 62 and the second heat exchanger 63.

[0099] Figure 6 This is a schematic diagram of the refrigerant system of the air conditioner 10 during dehumidification operation in an embodiment. (Example) Figure 6 As shown, during dehumidification operation, each valve is controlled to allow the same refrigerant flow as during refrigeration operation. However, during dehumidification operation, the three-way valve 34 is controlled to connect the first bypass pipe 53 and the second bypass pipe 54. Furthermore, the on / off valve 35 is in the closed state. Therefore, during dehumidification operation, refrigerant flows from the compressor 23 outlet 23b to the outdoor heat exchanger 21. The refrigerant flowing from the outdoor heat exchanger 21 does not flow to the other end 53b of the first bypass pipe 53, but instead flows into the indoor heat exchanger 41. The refrigerant flowing from the indoor heat exchanger 41 flows into the compressor 23 suction port 23a via the first bypass pipe 53 and the second bypass pipe 54. Figure 6 The arrow represents an example of refrigerant flow during dehumidification operation.

[0100] In the first heat exchanger 62, the refrigerant flowing in region 51d of the first piping 51 undergoes heat transfer to the refrigerant passing through the first bypass piping 53, whereby the refrigerant is heated and vaporized. At this time, the specific volume of the refrigerant increases. Furthermore, in the second heat exchanger 63, the refrigerant flowing in region 51a of the second piping 52 undergoes heat transfer to the refrigerant passing through the first bypass piping 53, whereby the refrigerant is heated and vaporized. At this time, the specific volume of the refrigerant also increases.

[0101] Here, the rated evaporation temperature of the refrigerant in the indoor heat exchanger 41 is, for example, about 13°C, and its pressure is about 1.1 MPa. During dehumidification operation, when the outlet temperature of the indoor unit 12 is reduced to, for example, 5°C, the evaporation temperature on the low-pressure side of the refrigerant is about 3°C, and its pressure is about 0.8 MPa. That is, during dehumidification operation, the low-pressure side of the refrigerant is as low as 0.3 MPa. To address this, the work done by the compressor 23 only needs to be increased by an amount corresponding to the pressure reduction, but at this time, the power consumption of the compressor 23 will increase. Therefore, in this embodiment, as described above, during dehumidification operation, by directing the refrigerant to the first bypass pipe 53 and heating the refrigerant in the first heat exchanger 62 and the second heat exchanger 63, the pressure of the refrigerant is increased and superheated, and the refrigerant is returned to the compressor 23. As a result, it is not necessary to increase the frequency of the compressor 23, thus achieving energy saving of the air conditioner 10.

[0102] In other words, during dehumidification operation, the airflow of the indoor fan 42 is reduced compared to cooling operation to dehumidify, thus reducing the amount of heat exchange in the indoor heat exchanger 41. Consequently, the temperature of the indoor heat exchanger 41 decreases, making it difficult for the refrigerant returning from the indoor heat exchanger 41 to the compressor 23 to vaporize. Therefore, in this embodiment, the unvaporized refrigerant is heated in the first heat exchanger 62 and the second heat exchanger 63, thereby vaporizing it.

[0103] Figure 7 This is a block diagram illustrating an example of the hardware configuration of the control device 14 in this embodiment. The control device 14, for example, consists of... Figure 7 The computer 100 with the hardware configuration shown is implemented.

[0104] Computer 100 includes, for example, CPU 101, ROM 102, RAM 103, storage device 104, and interface (I / F) 106. CPU 101, ROM 102, RAM 103, storage device 104, and I / F 106 are connected via a bus.

[0105] CPU 101 can expand the program stored in storage device 104 to RAM 103 for execution, and control various parts to perform input / output or data processing. ROM 102 stores a boot program that reads the operating system boot program from storage device 104 into RAM 103.

[0106] Storage device 104 is, for example, a flash memory. Storage device 104 stores the operating system, applications, and data. These programs are files in installable or executable formats, recorded on a computer-readable recording medium for distribution. Alternatively, programs can also be distributed by downloading from a server.

[0107] I / F106 is, for example, an interface device for connecting to temperature sensors 71A-71J, human body sensor 72, outdoor fan drive circuit 81, indoor fan drive circuit 82, inverter circuit 83, four-way valve drive circuit 84, first expansion valve drive circuit 85, second expansion valve drive circuit 86, third expansion valve drive circuit 87, three-way valve drive circuit 88, and on / off valve drive circuit 89.

[0108] The program executed in the computer 100 of this embodiment can be provided in the form of an installable or executable file on a computer-readable recording medium such as a CD-ROM, floppy disk (FD), CD-R, or DVD.

[0109] Alternatively, the program executed by the computer 100 of this embodiment can be stored on a computer connected to a network such as the Internet, and provided by downloading it via the network. Alternatively, the program executed by the computer 100 of this embodiment can be provided or distributed via a network such as the Internet. Alternatively, the program of this embodiment can be pre-assembled into the ROM 102 or the like for provision.

[0110] The program that enables the computer 100 to function as a control device 14 is composed of modules including a temperature acquisition module, an operation switching module, an outdoor fan control module, an indoor fan control module, a compressor control module, and a valve control module. The computer 100, as actual hardware, is executed by a processor (CPU 101) that reads the program from a storage medium (storage device 104, etc.), thereby loading each module onto the main storage device (RAM 103). Thus, the processor (CPU 101) functions as... Figure 3The temperature acquisition unit 91, operation switching unit 92, outdoor fan control unit 93, indoor fan control unit 94, compressor control unit 95, and valve control unit 96 function as such. Alternatively, the computer 100 can implement part or all of the configuration of the temperature acquisition unit 91, operation switching unit 92, outdoor fan control unit 93, indoor fan control unit 94, compressor control unit 95, and valve control unit 96 via hardware.

[0111] As described above, in this embodiment, the air conditioner 10 includes an indoor heat exchanger 41, an outdoor heat exchanger 21, a first piping 51, a second piping 52, a compressor 23, a four-way valve 25, a first expansion valve 31, a first bypass piping 53, a heat exchange section 45, a second expansion valve 32 (first valve), a third expansion valve 33 (second valve), and a control device 14. The first piping 51 connects the indoor heat exchanger 41 and the outdoor heat exchanger 21, allowing refrigerant to flow. The second piping 52 connects the outdoor heat exchanger 21 and the indoor heat exchanger 41, allowing refrigerant to flow. The compressor 23 is located on the first piping 51 and has a refrigerant inlet 23a and a refrigerant outlet 23b. The four-way valve 25 is located on the first piping 51 and can change the direction of refrigerant flow. The first expansion valve 31 is located on the second piping 52. The first bypass pipe 53 has one end 53a connected to the first pipe 51 between the indoor heat exchanger 41 and the outlet 23b, and another end 53b connected to the second pipe 52 between the indoor heat exchanger 41 and the first expansion valve 31, and is capable of supplying refrigerant flow. The heat exchange section 45 exchanges heat with the first bypass pipe 53 via at least one of the first pipe 51 between the outdoor heat exchanger 21 and the suction port 23a, and the second pipe 52 between the outdoor heat exchanger 21 and the first expansion valve 31. The second expansion valve 32 is provided between one end 53a and the first bypass pipe 53, and is capable of adjusting the amount of refrigerant flowing in the first bypass pipe 53. The third expansion valve 33 is provided between the other end 53b and the first bypass pipe 53, and is capable of adjusting the amount of refrigerant flowing in the first bypass pipe 53. The control device 14 controls the compressor 23, the four-way valve 25, the first expansion valve 31, the second expansion valve 32, and the third expansion valve 33.

[0112] Here, for example, when the required capacity of the air conditioner 10 is low, sometimes even when the compression capacity of the compressor 23 is set to the minimum (lowest capacity), the air conditioner 10 may still exceed the required capacity. In this case, if the compressor 23 is repeatedly stopped temporarily and then restarted in order to make the air conditioner 10 operate at the required capacity, refrigerant backflow may occur, and the power consumption of the air conditioner 10 may easily increase. In contrast, in this embodiment, the second expansion valve 32 and the third expansion valve 33 are controlled to allow the refrigerant to flow in the first bypass pipe 53, thereby enabling a portion of the refrigerant discharged from the compressor 23 (the remaining refrigerant) to be vaporized through the heat exchange section 45 without passing through the indoor heat exchanger 41 and return to the compressor 23. In this case, the energy of the refrigerant returning to the compressor 23 via the first bypass pipe 53 will not be exchanged in the indoor heat exchanger 41, so it is not necessary to stop the compressor 23. That is, in this embodiment, continuous operation of the compressor 23 can be achieved. Thus, in this embodiment, there is no need to repeatedly start and stop the compressor 23, thereby suppressing the increase in power consumption of the air conditioner 10 and achieving energy saving of the air conditioner 10. Furthermore, as described above, since there is no need to repeatedly start and stop the compressor 23, the temperature of the indoor heat exchanger 41 tends to remain constant. Therefore, the room temperature tends to remain constant.

[0113] Furthermore, the heat exchange section 45 includes a first heat exchanger 62 and a second heat exchanger 63. The first heat exchanger 62 performs heat exchange between a first piping 51 and a first bypass piping 53 between the outdoor heat exchanger 21 and the suction inlet 23a. The second heat exchanger 63 performs heat exchange between a second piping 52 and a first bypass piping 53 between the outdoor heat exchanger 21 and the first expansion valve 31. The second expansion valve 32 is disposed on the first bypass piping 53 between one end 53a and the first heat exchanger 62. The third expansion valve 33 is disposed on the first bypass piping 53 between the other end 53b and the second heat exchanger 63.

[0114] With this configuration, since the heat exchange section 45 has a first heat exchanger 62 and a second heat exchanger 63, the refrigerant returning to the compressor 23 via the first bypass pipe 53 can be further vaporized.

[0115] Furthermore, the air conditioner 10 includes, for example, a three-way valve 34, a second bypass pipe 54, and an on / off valve 35. The three-way valve 34 is located on the first bypass pipe 53 and can change the direction of refrigerant flow. The second bypass pipe 54 is connected to the first pipe 51 between the compressor 23 and the four-way valve 25, as well as the three-way valve 34, and can supply refrigerant flow. The on / off valve 35 is located on the first pipe 51 between one end 53a and the four-way valve 25.

[0116] With this configuration, during dehumidification operation, by controlling the three-way valve 34 to allow the refrigerant to return from the first bypass pipe 53 to the compressor 23 via the second bypass pipe 54, the refrigerant can be vaporized in the heat exchange section 45. Therefore, during dehumidification operation, since it is not necessary to vaporize the refrigerant in the indoor heat exchanger 41, the airflow of the indoor fan 42 can be reduced. Consequently, the temperature difference between the inside and outside of the indoor heat exchanger 41 can be increased, thus improving the dehumidification capacity.

[0117] In addition, the first heat exchanger 62 and the second heat exchanger 63 are heat storage materials.

[0118] With this configuration, the heat of the refrigerant can be stored in the first heat exchanger 62 and the second heat exchanger 63.

[0119] Furthermore, in the above embodiments, an example is shown where the first heat exchanger 62 and the second heat exchanger 63 are heat storage materials, but this is not a limitation. For example, the first heat exchanger 62 and the second heat exchanger 63 may also be double-layered piping.

[0120] Furthermore, in the above embodiments, an example is shown where the heat exchange unit 45 has both a first heat exchanger 62 and a second heat exchanger 63, but it is not limited to this. For example, the heat exchange unit 45 may also have only one of the first heat exchanger 62 and the second heat exchanger 63.

[0121] Furthermore, the above embodiment shows an example with a second bypass pipe 54, but it is not limited to this. For example, the second bypass pipe 54 may not be provided.

[0122] Several embodiments of the present invention have been described, but these embodiments are provided by way of example and are not intended to limit the scope of the invention. These new embodiments can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, and are included in the scope of the invention described in the claims and its equivalents.

Claims

1. An air conditioner, comprising: Indoor heat exchanger; Outdoor heat exchanger; The first piping connects the indoor heat exchanger to the outdoor heat exchanger to allow refrigerant to flow. The second piping connects the outdoor heat exchanger to the indoor heat exchanger to allow the refrigerant to flow. The compressor, installed in the first piping, has an inlet for drawing in the refrigerant and an outlet for discharging the refrigerant. A four-way valve, installed on the first piping mentioned above, is capable of changing the direction of refrigerant flow. An expansion valve is installed in the second piping mentioned above; The first bypass pipe has one end connected to the first pipe between the indoor heat exchanger and the compressor, and the other end connected to the second pipe between the indoor heat exchanger and the expansion valve, and is capable of supplying the refrigerant flow. The heat exchange section exchanges heat with at least one of the first piping between the outdoor heat exchanger and the suction inlet and the second piping between the outdoor heat exchanger and the expansion valve, and the first bypass piping. The first valve, provided in the first bypass pipe between the aforementioned end and the aforementioned heat exchange section, is capable of adjusting the amount of refrigerant flowing in the aforementioned first bypass pipe. The second valve, disposed between the other end and the heat exchange section of the first bypass pipe, is capable of adjusting the amount of refrigerant flowing in the first bypass pipe; and The control device controls the four-way valve, the expansion valve, the first valve, and the second valve.

2. The air conditioner according to claim 1, wherein, The above-mentioned heat exchange section has: The first heat exchanger performs heat exchange between the first piping between the outdoor heat exchanger and the compressor and the first bypass piping; and The second heat exchanger exchanges heat between the second piping between the outdoor heat exchanger and the expansion valve and the first bypass piping. The first valve is located in the first bypass pipe between the first end and the first heat exchanger. The second valve is located in the first bypass piping between the other end and the second heat exchanger.

3. The air conditioner according to claim 1 or 2, comprising: A three-way valve, installed on the first bypass pipe, is capable of changing the direction of refrigerant flow. A second bypass pipe, connected to the first pipe between the compressor and the four-way valve, and the three-way valve, is capable of supplying the refrigerant flow; and An on / off valve is provided in the first piping between the aforementioned end and the aforementioned four-way valve.

4. The air conditioner according to claim 2, wherein, The first heat exchanger and the second heat exchanger mentioned above are heat storage materials.

Images