JP7565889B2 - Air conditioners - Google Patents

Description

An embodiment of the present invention relates to an air conditioner.

Air conditioners, such as air conditioners, regulate the indoor temperature by condensing and evaporating a refrigerant in a refrigeration cycle that includes an indoor heat exchanger and an outdoor heat exchanger.

JP 2006-29738 A

In this type of air conditioner, it would be beneficial if it were possible to prevent a decrease in the heat exchange efficiency of the indoor heat exchanger and the outdoor heat exchanger.

One example of the problem that the present invention solves is to obtain an air conditioner that can prevent a decrease in the heat exchange efficiency of the indoor heat exchanger and the outdoor heat exchanger.

An air conditioner according to an embodiment of the present invention includes 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 three-way valve, a third pipe, a first on-off valve, a heat storage material, a fourth pipe, a second on-off valve, and a control device. The first pipe connects the indoor heat exchanger and the outdoor heat exchanger, and a refrigerant flows through it. The second pipe connects the outdoor heat exchanger and the indoor heat exchanger, and the refrigerant flows through it. The compressor is provided in the first pipe and has an intake port for sucking in the refrigerant and an outlet port for discharging the refrigerant. The four-way valve is provided in the first pipe and is capable of changing the direction in which the refrigerant flows. The expansion valve is provided in the second pipe. The first three-way valve is provided in the second pipe between the indoor heat exchanger and the expansion valve, and is capable of changing the direction in which the refrigerant flows. The third pipe has one end connected to the first three-way valve and the other end connected to the second pipe between the outdoor heat exchanger and the expansion valve, and the refrigerant can flow through it. The first on-off valve is provided in the third pipe. The heat storage material is thermally connected to the second pipe between the outdoor heat exchanger and the expansion valve, and is thermally connected to the third pipe between the one end of the third pipe and the first on-off valve. The fourth pipe has a fourth pipe having one end connected to the third pipe between the first on-off valve and the heat storage material, and the other end connected to the second pipe between the indoor heat exchanger and the first three-way valve. The second on-off valve is provided in the fourth pipe. The control device controls the four-way valve, the expansion valve, the first three-way valve, the first on-off valve, and the second on-off valve.

The air conditioner includes, for example, a second three-way valve and a fifth pipe. The second three-way valve is provided in the second pipe between the expansion valve and the heat storage material, and is capable of changing the direction in which the refrigerant flows. The fifth pipe is connected to the third pipe between the first three-way valve and the heat storage material, and to the second three-way valve. The amount of heat that can be transferred per unit time between the third pipe and the heat storage material is greater than the amount of heat that can be transferred per unit time between the second pipe and the heat storage material. The control device controls the second three-way valve.

The air conditioner includes, for example, a heat exchanger. The heat exchanger exchanges heat between the first pipe between the indoor heat exchanger and the four-way valve and the first pipe between the outdoor heat exchanger and the four-way valve.

The air conditioner includes, for example, a detection sensor. The detection sensor detects a human or an animal in the room in which the indoor heat exchanger is installed. When the detection sensor does not detect the human or the animal, the control device performs a cold storage operation to cool the heat storage material.

In the air conditioner, for example, the control device stops the cold storage operation when the detection sensor detects the human or animal.

When the degree of cold storage of the heat storage material reaches a specified degree, the control device controls the first three-way valve so that refrigerant flows through the third pipe during cooling operation, and when the degree of cold storage of the heat storage material does not reach the specified degree, the control device controls the first three-way valve so that refrigerant does not flow through the third pipe during cooling operation.

The above air conditioner can provide an air conditioner that can prevent a decrease in the heat exchange efficiency of the indoor heat exchanger and the outdoor heat exchanger.

FIG. 1 is a refrigerant system diagram that illustrates an air conditioner according to a first embodiment during cooling operation. FIG. 2 is a refrigerant system diagram that illustrates the air conditioner of the first embodiment during heating operation. FIG. 3 is a block diagram functionally showing the configuration of the air conditioner of the first embodiment. FIG. 4 is a Mollier diagram of the air conditioner of the first embodiment. FIG. 5 is a refrigerant system diagram that illustrates the air conditioner during the heat storage operation according to the first embodiment. FIG. 6 is a flowchart showing an example of cold storage operation control of the air conditioner of the first embodiment. FIG. 7 is a refrigerant system diagram that illustrates the air conditioner according to the second embodiment during cooling operation. FIG. 8 is a flowchart showing an example of cooling operation control of the air conditioner according to the second embodiment. FIG. 9 is a block diagram illustrating an example of a hardware configuration of the control device according to the first and second embodiments.

(First embodiment)
The first embodiment will be described below with reference to FIGS. 1 to 6. In this specification, components according to the embodiment and descriptions of the components may be described in a plurality of ways. The components and their descriptions are merely examples and are not limited by the expressions in this specification. The components may be identified by names different from those in this specification. The components may also be described by expressions different from those in this specification.

Figure 1 is a refrigerant system diagram that shows an outline of the air conditioner 10 during cooling operation in this embodiment. The air conditioner 10 is, for example, a home air conditioner. Note that the air conditioner 10 is not limited to this example and may be another type of air conditioner, such as a commercial air conditioner.

As shown in FIG. 1, the air conditioner 10 has an outdoor unit 11, an indoor unit 12, refrigerant piping 13, and a control device 14. The outdoor unit 11 is placed, for example, outdoors. The indoor unit 12 is placed, for example, indoors.

The air conditioner 10 has a refrigeration cycle in which an outdoor unit 11 and an indoor unit 12 are connected by refrigerant piping 13. Refrigerant flows between the outdoor unit 11 and the indoor unit 12 through the refrigerant piping 13. In addition, the outdoor unit 11 and the indoor unit 12 are electrically connected to each other by, for example, electrical wiring.

The outdoor unit 11 has an outdoor heat exchanger 21, an outdoor blower fan 22, a compressor 23, an accumulator 24, a four-way valve 25, an expansion valve 31, a first three-way valve 32, a second three-way valve 33, a first on-off valve 34, and a second on-off valve 35. The indoor unit 12 has an indoor heat exchanger 41 and an indoor blower fan 42.

The refrigerant piping 13 is a pipe made of a metal such as copper or aluminum. The refrigerant piping 13 has a first piping 51, a second piping 52, a third piping 53, a fourth piping 54, and a fifth piping 55. The first piping 51 connects the indoor heat exchanger 41 and the outdoor heat exchanger 21. The compressor 23, the accumulator 24, and the four-way valve 25 are provided in the first piping 51. The second piping 52 connects the outdoor heat exchanger 21 and the indoor heat exchanger 41. The expansion valve 31, the first three-way valve 32, and the second three-way valve 33 are provided in the second piping 52. The third piping 53 is connected to the second piping 52 and the first three-way valve 32. The first opening and closing valve 34 is provided in the third piping 53. The fourth pipe 54 is connected to the second pipe 52 and the third pipe 53. The second on-off valve 35 is provided in the fourth pipe 54. The fifth pipe 55 is connected to the second three-way valve 33 and the third pipe 53.

In cooling operation, the refrigerant flows from the indoor heat exchanger 41 to the outdoor heat exchanger 21 through the first pipe 51, and flows from the outdoor heat exchanger 21 to the indoor heat exchanger 41 through the second pipe 52 and the third pipe 53. In cooling operation, the first on-off valve 34 is closed and the second on-off valve 35 is open. The arrows in FIG. 1 show an example of the flow of the refrigerant during cooling operation.

Figure 2 is a refrigerant system diagram that shows the air conditioner 10 during heating operation in this embodiment. As shown in Figure 2, during heating operation, the refrigerant flows from the outdoor heat exchanger 21 to the indoor heat exchanger 41 through the first pipe 51, and flows from the indoor heat exchanger 41 to the outdoor heat exchanger 21 through the second pipe 52. During heating operation, the first opening/closing valve 34 and the second opening/closing valve 35 are in a closed state. The arrows in Figure 2 show an example of the flow of the refrigerant during heating operation.

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 release heat from the refrigerant depending on the direction of refrigerant flow. The outdoor blower fan 22 blows air toward the outdoor heat exchanger 21, promoting heat exchange between the refrigerant and air in the outdoor heat exchanger 21. In other words, the outdoor blower fan 22 generates an airflow that exchanges heat with the outdoor heat exchanger 21.

The compressor 23 has an intake port 23a and an exhaust port 23b. The compressor 23 draws in the refrigerant from the intake port 23a and exhausts the compressed refrigerant from the exhaust port 23b. In this way, the compressor 23 compresses the refrigerant in the refrigeration cycle and causes the refrigerant to circulate.

The accumulator 24 is connected to the suction port 23a of the compressor 23. The accumulator 24 separates the gaseous refrigerant from the liquid refrigerant. This allows the compressor 23 to suck the gaseous refrigerant that has passed through the accumulator 24 from the suction port 23a. The accumulator 24 is configured integrally with the compressor 23, and can serve as the suction port of the compressor 23.

The four-way valve 25 is connected to the outdoor heat exchanger 21, the indoor heat exchanger 41, the discharge port 23b of the compressor 23, and the accumulator 24 (the suction port 23a of the compressor 23). The four-way valve 25 switches the flow paths connected to the outdoor heat exchanger 21, the indoor heat exchanger 41, the discharge port 23b of the compressor 23, and the accumulator 24 during heating operation and cooling operation, changing the direction in which the refrigerant flows. The four-way valve 25 is also called a switching valve.

As shown in FIG. 1, during cooling operation, the four-way valve 25 connects the outdoor heat exchanger 21 to the discharge port 23b of the compressor 23. Furthermore, during cooling operation, the four-way valve 25 connects the indoor heat exchanger 41 to the accumulator 24. As a result, 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 accumulator 24.

As shown in FIG. 2, during heating operation, the four-way valve 25 connects the outdoor heat exchanger 21 and the accumulator 24. Furthermore, during heating operation, the four-way valve 25 connects the indoor heat exchanger 41 and the discharge port 23b of the compressor 23. As a result, 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 accumulator 24.

The expansion valve 31 is, for example, an electromagnetic expansion valve. However, the expansion valve 31 may be another type of expansion valve. The expansion valve 31 adjusts the amount of refrigerant passing through by controlling the opening degree.

The indoor heat exchanger 41 of the indoor unit 12 absorbs heat as an evaporator or releases heat as a condenser depending on the direction of refrigerant flow. The indoor heat exchanger 41 is, for example, a so-called microchannel heat exchanger having a flat multi-hole tube with multiple small refrigerant flow paths formed therein as a heat transfer tube. The indoor heat exchanger 41 may be a so-called cross-fin heat exchanger having multiple plate-shaped heat transfer fins and heat transfer tubes that penetrate each heat transfer fin, or may be another type of heat exchanger. A diverter 36 is provided on the expansion valve 31 side of the indoor heat exchanger 41. The diverter 36 is connected to multiple refrigerant flow paths of the indoor heat exchanger 41. The diverter 36 is also called a distributor. The indoor blower fan 42 blows air toward the indoor heat exchanger 41 to promote heat exchange between the indoor heat exchanger 41 and the air. In other words, the indoor blower fan 42 generates an air flow that exchanges heat with the indoor heat exchanger 41.

In the air conditioner 10 in which the elements are arranged as described above, the first piping 51 has regions 51a, 51b, 51c, and 51d. Region 51a is a portion of the first piping 51 between the indoor heat exchanger 41 and the four-way valve 25. Region 51b is a portion of the first piping 51 between the four-way valve 25 and the accumulator 24. Region 51c is a portion of the first piping 51 between the discharge port 23b of the compressor 23 and the four-way valve 25. Region 51d is a portion of the first piping 51 between the four-way valve 25 and the outdoor heat exchanger 21.

The second pipe 52 has a region 52a and a region 52b. The region 52a is a part of the second pipe 52 between the outdoor heat exchanger 21 and the expansion valve 31. In detail, the region 52a is a region of the second pipe 52 from the outdoor heat exchanger 21 to the expansion valve 31 through the second three-way valve 33. The region 52b is connected in two directions different from the fifth pipe 55 in the second three-way valve 33. The region 52b is a part of the second pipe 52 between the expansion valve 31 and the indoor heat exchanger 41. In detail, the region 52b is a region of the second pipe 52 from the indoor heat exchanger 41 to the expansion valve 31 through the first three-way valve 32. The region 52b is connected in two directions different from one end 53a of the third pipe 53 in the first three-way valve 32.

The third pipe 53 has one end 53a and the other end 53b. The one end 53a is connected to the first three-way valve 32. The other end 53b is connected to the second pipe 52 between the outdoor heat exchanger 21 and the expansion valve 31. That is, the other end 53b is provided in the region 52a of the second pipe 52.

The fourth pipe 54 has one end 54a and the other end 54b. The one end 54a is connected to the third pipe 53 between the first on-off valve 34 and the heat storage material 63. The other end 54b is connected to the second pipe 52 between the indoor heat exchanger 41 and the first three-way valve 32. In other words, the other end 54b is provided in the region 52b of the second pipe 52.

The fifth pipe 55 is connected to the third pipe 53 between the first three-way valve 32 and the heat storage material 63, and to the second three-way valve 33.

The first and second on-off valves 34 and 35 allow the refrigerant to flow when open and block the refrigerant when closed.

The outdoor unit 11 of this embodiment also has a heat storage material 62 and a heat storage material 63. The heat storage material 62 and the heat storage material 63 have, for example, a latent heat storage material filled in a block-shaped container. The latent heat storage material is, for example, calcium chloride. The heat storage material 62 and the heat storage material 63 may have another latent heat storage material. The heat storage material 62 and the heat storage material 63 in this embodiment are, for example, heat storage materials that can be used in a temperature range of about 10°C to about 100°C. The heat storage material 62 is an example of a heat exchanger.

The heat storage material 62 and the heat storage material 63 are not limited to the above examples, and may be, for example, other heat storage materials such as sensible heat storage materials, or may be heat storage materials that can be used in other temperature ranges. In addition, the heat storage material 62 and the heat storage material 63 may be different heat storage materials.

The heat storage material 62 is thermally connected to the region 51a of the first pipe 51 between the four-way valve 25 and the indoor heat exchanger 41, and to the region 51d of the first pipe 51 between the outdoor heat exchanger 21 and the four-way valve 25. For example, the region 51a and the region 51d of the first pipe 51 are spaced apart from each other and pass through the heat storage material 62.

The heat storage material 62 configured in this manner exchanges heat between the region 51a and the region 51d of the first pipe 51. That is, in the heat storage material 62, heat exchange occurs between the refrigerant in the region 51a of the first pipe 51 and the refrigerant in the region 51d.

The heat storage material 62 can store a larger amount of heat (heat storage capacity) than the regions 51a and 51d. In addition, the regions 51a and 51d are made of metal and are in close contact with the latent heat storage material of the heat storage material 62. For this reason, heat conduction is likely to occur between the regions 51a and 51d and the latent heat storage material of the heat storage material 62.

The heat storage material 63 is thermally connected to the region 52a of the second pipe 52 between the outdoor heat exchanger 21 and the expansion valve 31 and to the third pipe 53. For example, the region 52a and the third pipe 53 are separated from each other and penetrate the heat storage material 63. That is, the region 52a of the second pipe 52 has a through portion 52c that penetrates the heat storage material 63. In other words, the through portion 52c is a part of the region 52a. Also, the third pipe 53 has a through portion 53c that penetrates the heat storage material 63. In other words, the through portion 53c is a part of the third pipe 53. Therefore, the heat storage material 63 thermally connects the through portion 52c of the region 52a and the through portion 53c of the third pipe 53 to each other. The heat storage material 63 configured in this manner exchanges heat between the heat storage material 63 and the through-hole 52c in the region 52a of the second pipe 52 and the through-hole 53c of the third pipe 53.

The heat storage material 63 has a larger heat storage capacity than the third pipe 53 and the region 52b. The third pipe 53 and the region 52a are made of metal and are in close contact with the latent heat storage material of the heat storage material 63. For this reason, heat conduction is likely to occur between the third pipe 53 and the region 52a and the latent heat storage material of the heat storage material 63. The third pipe 53 and the region 52a of the second pipe 52 are configured so that the amount of heat transferable per unit time between the third pipe 53 and the heat storage material 63 is greater than the amount of heat transferable per unit time between the region 52a of the second pipe 52 and the heat storage material 63. For example, the penetration portion 53c of the third pipe 53 is formed in a spiral shape or one or more folds, and the penetration portion 52c of the region 52a of the second pipe 52 is formed in a straight line. As a result, the contact area between the third pipe 53 and the heat storage material 63 is larger than the contact area between the region 52a of the second pipe 52 and the heat storage material 63.

The air conditioner 10 also has temperature sensors 71A-71J and a human presence sensor 72.

The temperature sensor 71A is disposed, for example, in the housing of the outdoor unit 11. The temperature sensor 71A detects the outside air temperature of the outdoor environment in which the outdoor unit 11 is disposed.

The temperature sensor 71B is provided in the outdoor heat exchanger 21. The temperature sensor 71B detects the temperature of the refrigerant flowing through the outdoor heat exchanger 21. For example, the temperature sensor 71B is disposed at a position where the saturation temperature of the refrigerant flowing through the outdoor heat exchanger 21 can be obtained.

The temperature sensor 71C is disposed, for example, in the housing of the indoor unit 12. The temperature sensor 71C detects the temperature (room temperature) of the room in which the indoor unit 12 is disposed.

Temperature sensor 71D is provided on the four-way valve 25 side of the indoor heat exchanger 41 in the indoor unit 12, and detects the temperature of the refrigerant on the four-way valve 25 side of the indoor heat exchanger 41. Temperature sensor 71E is provided in the indoor heat exchanger 41. Temperature sensor 71E detects the temperature of the refrigerant flowing through the indoor heat exchanger 41. Temperature sensor 71F is provided on the expansion valve 31 side of the indoor heat exchanger 41 in the indoor unit 12, and detects the temperature of the refrigerant on the expansion valve 31 side of the indoor heat exchanger 41. For example, temperature sensors 71D to 71F are positioned where the saturation temperature of the refrigerant can be obtained.

The temperature sensor 71G is provided in the heat storage material 62. The temperature sensor 71G detects the temperature of the heat storage material 62. The temperature sensor 71H is provided in the heat storage material 63. The temperature sensor 71H detects the temperature of the heat storage material 63. In detail, the temperature sensor 71H detects the temperature of the portion of the heat storage material 63 that contacts the penetration portion 53c of the third pipe 53 and is on the second opening/closing valve 35 side.

The temperature sensor 71I is provided in the region 51b of the first pipe 51, near the accumulator 24. The temperature sensor 71H detects the temperature of the refrigerant flowing through the region 51b, near the accumulator 24.

The temperature sensor 71J is provided in the region 52a of the second pipe 52 between the heat storage material 63 and the expansion valve 31. The temperature sensor 71J detects the temperature of the refrigerant flowing through the region 52a in the vicinity of the heat storage material 63.

The human presence sensor 72 is provided in the indoor unit 12. The human presence sensor 72 can detect humans and animals in the room in which the indoor unit 12 is installed. Animals include, for example, dogs and cats. The human presence sensor 72 is an example of a detection sensor.

The control device 14 has, 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 by electrical wiring. At least one of the outdoor control device 14a and the indoor control device 14b is, for example, a computer having a control device such as a CPU (Central Processing Unit) or a microcontroller, a ROM (Read Only Memory), a RAM (Random Access Memory), and a storage device such as a flash memory. Note that the control device 14 is not limited to this example. For example, the control device 14 may have only one of the outdoor control device 14a and the indoor control device 14b. In this case, one of the outdoor control device 14a and the indoor control device 14b may control the entire air conditioner 10.

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

The control device 14 controls the outdoor unit 11 and the indoor unit 12, so that the air conditioner 10 performs cooling operation, heating operation, cold storage operation, and other operations. The indoor control device 14b may receive signals, for example, from a remote controller, or may receive signals from an information terminal such as a smartphone via a communication device.

Figure 3 is a block diagram showing the functional configuration of the air conditioner 10 of this embodiment. As shown in Figure 3, the air conditioner 10 of this embodiment further has an outdoor fan drive circuit 81, an indoor fan drive circuit 82, an inverter circuit 83, a four-way valve drive circuit 84, an expansion valve drive circuit 85, a first three-way valve drive circuit 86, a second three-way valve drive circuit 87, a first on-off valve drive circuit 88, and a second on-off valve drive circuit 89.

The outdoor fan drive circuit 81 is a drive circuit for the outdoor blower fan 22. The indoor fan drive circuit 82 is a drive circuit for the indoor blower fan 42. The inverter circuit 83 inverter controls the compressor 23 and changes the frequency of the compressor 23. The inverter circuit 83 is, for example, a PAM (Pulse Amplitude Modulation) type inverter circuit. Note that the inverter circuit 83 is not limited to this example.

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

The control device 14 is connected to the temperature sensors 71A-71J, the human presence sensor 72, the outdoor fan drive circuit 81, the indoor fan drive circuit 82, the inverter circuit 83, the four-way valve drive circuit 84, the expansion valve drive circuit 85, the first three-way valve drive circuit 86, the second three-way valve drive circuit 87, the first on-off valve drive circuit 88, and the second 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.

The temperature acquisition unit 91 uses the temperature sensors 71A to 72J to acquire the outside air temperature, the temperature of the refrigerant, the temperature of the heat storage material 62, and the temperature of the heat storage material 63. For example, the temperature acquisition unit 91 calculates the outside air temperature, the temperature of the refrigerant, the temperature of the heat storage material 62, and the temperature of the heat storage material 63 from the output signals of the temperature sensors 71A to 71J.

The operation switching unit 92 switches the air conditioner 10 between cooling operation, heating operation, and cold storage operation. The operation switching unit 92 may also switch the operation of the air conditioner 10 to another operation mode. A human presence sensor 72 is connected to the operation switching unit 92.

The outdoor fan control unit 93 controls the outdoor blower fan 22. For example, the outdoor fan control unit 93 controls the outdoor fan drive circuit 81 to control the rotation speed of the motor of the outdoor blower fan 22.

The indoor fan control unit 94 controls the indoor blower fan 42. For example, the indoor fan control unit 94 controls the rotation speed of the motor of the indoor blower fan 42 by controlling the indoor fan drive circuit 82.

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

The valve control unit 96 controls the four-way valve 25, the expansion valve 31, the first three-way valve 32, the second three-way valve 33, the first on-off valve 34, and the second on-off valve 35. The valve control unit 96 drives the actuator of the four-way valve 25 by controlling the four-way valve drive circuit 84, and changes the direction of the refrigerant flow to the four-way valve 25. The valve control unit 96 changes the opening degree of the expansion valve 31 by controlling the expansion valve drive circuit 85. The valve control unit 96 changes the direction of the refrigerant flow to the first three-way valve 32 and the second three-way valve 33 by controlling the first three-way valve drive circuit 86 and the second three-way valve drive circuit 87. The valve control unit 96 changes the state (open state, closed state) of the first on-off valve 34 and the second on-off valve 35 by controlling the first on-off valve drive circuit 88 and the second on-off valve drive circuit 89.

The cooling operation, heating operation, and cold storage operation of the air conditioner 10 of this embodiment are described below. Note that the air conditioner 10 is not limited to the cooling operation, heating operation, and cold storage operation, and can perform other operations such as a defrosting operation. Also, the cooling operation, heating operation, and cold storage operation of the air conditioner 10 are not limited to the examples described below.

For example, when the air conditioner 10 starts and the cooling operation starts at the same time, the outdoor blower fan 22, the compressor 23, and the indoor blower fan 42 are stopped. In this case, the outdoor fan control unit 93, the indoor fan control unit 94, and the compressor control unit 95 start the outdoor blower fan 22, the compressor 23, and the indoor blower fan 42 when the cooling operation starts.

During cooling operation, the outdoor fan control unit 93 adjusts the rotation speed of the outdoor blower fan 22. The indoor fan control unit 94 adjusts the rotation speed of the indoor blower 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 blower fan 42 between weak wind (low speed) operation and strong wind (high speed) operation in response to the air temperature in the room where the indoor unit 12 is installed or a signal input from a remote controller.

When the cooling operation is started, the valve control unit 96 changes the direction of the refrigerant flow through the four-way valve 25, the first three-way valve 32, and the second three-way valve 33. At this time, the valve control unit 96 also closes the first on-off valve 34 and opens the second on-off valve 35. This connects the outdoor heat exchanger 21 to the discharge port 23b of the compressor 23, and connects the indoor heat exchanger 41 to the accumulator 24 (the suction port 23a of the compressor 23). That is, the control device 14 executes the cooling operation to control the four-way valve 25 so that the refrigerant flows from the discharge port 23b of the compressor 23 to the outdoor heat exchanger 21. The valve control unit 96 also controls the first three-way valve 32 and the second three-way valve 33 so that the refrigerant does not flow through the third pipe 53 and the fourth pipe 54 to the fifth pipe 55. That is, as shown in FIG. 1, in cooling operation, the refrigerant discharged from the compressor 23 passes through the area 51d of the first pipe 51, the outdoor heat exchanger 21, the area 52a of the second pipe 52, the second three-way valve 33, the expansion valve 31, the first three-way valve 32, the third pipe 53, the fourth pipe 54, the area 52b of the second pipe 52, and the diverter 36 to enter the indoor heat exchanger 41. The refrigerant leaving the indoor heat exchanger 41 passes through the area 51a of the first pipe 51 and returns to the compressor 23.

During cooling operation, the high-temperature, high-pressure gaseous refrigerant discharged from the discharge port 23b of the compressor 23 passes through the four-way valve 25 and the heat storage material 62, and dissipates heat in the outdoor heat exchanger 21. The medium-temperature, medium-pressure liquid refrigerant condensed in the outdoor heat exchanger 21 passes through the heat storage material 63, and is decompressed by the expansion valve 31. At this time, the refrigerant dissipates heat in the heat storage material 62. The dissipated heat is transferred to the heat storage material 62. The refrigerant is also cooled by the heat storage material 63.

The low-temperature, low-pressure, gas-liquid two-phase refrigerant that is decompressed by the expansion valve 31 and passes through the third pipe 53 is further cooled by the heat storage material 63, and the gas turns to liquid, remaining only as liquid. The refrigerant then absorbs heat in the indoor heat exchanger 41. The gas-liquid two-phase refrigerant that has evaporated in the indoor heat exchanger 41 passes through the heat storage material 62 and the four-way valve 25, and returns to the intake port 23a of the compressor 23. At this time, the refrigerant is heated by the heat storage material 62, and the liquid turns to gas, remaining only as gas.

Next, heating operation will be described. For example, when the air conditioner 10 is started and the heating operation starts simultaneously, the outdoor blower fan 22, the compressor 23, and the indoor blower fan 42 are stopped. In this case, the outdoor fan control unit 93, the indoor fan control unit 94, and the compressor control unit 95 start the outdoor blower fan 22, the compressor 23, and the indoor blower fan 42 when the heating operation starts.

When the heating operation is started, the four-way valve 25, the first three-way valve 32, and the second three-way valve 33 change the direction of the refrigerant flow. At this time, the valve control unit 96 closes the first on-off valve 34 and the second on-off valve 35. As a result, the indoor heat exchanger 41 and the discharge port 23b of the compressor 23 are connected, and the outdoor heat exchanger 21 and the accumulator 24 (the suction port 23a of the compressor 23) are connected. That is, the control device 14 executes a heating operation to control the four-way valve 25 so that the refrigerant flows from the discharge port 23b of the compressor 23 to the indoor heat exchanger 41. In addition, the four-way valve 25 and the suction port 23a of the compressor 23 are connected via the region 51b of the first pipe 51. In addition, at this time, the refrigerant does not flow through the third pipe 53, the fourth pipe 54, and the fifth pipe 55. In addition, the valve control unit 96 controls the first three-way valve 32 and the second three-way valve 33 so that the refrigerant does not flow through the second pipe 52 to the third pipe 53, the fourth pipe 54, and the fifth pipe 55. That is, as shown in FIG. 2, in the heating operation, the refrigerant discharged from the compressor 23 passes through the area 51a of the first pipe 51, the indoor heat exchanger 41, the area 52b of the second pipe 52, the first three-way valve 32, the expansion valve 31, the area 52a of the second pipe 52, and the second three-way valve 33, and enters the outdoor heat exchanger 21. The refrigerant discharged from the outdoor heat exchanger 21 passes through the area 51d of the first pipe 51 and returns to the compressor 23.

During heating operation, the high-temperature, high-pressure gaseous refrigerant discharged from the discharge port 23b of the compressor 23 flows through the heat storage material 62, the indoor heat exchanger 41, the expansion valve 31, and the heat storage material 63 to the outdoor heat exchanger 21. At this time, the refrigerant heats (dissipates heat) the heat storage material 62 and is cooled by the heat storage material 63.

The refrigerant that flows out of the outdoor heat exchanger 21 passes through the heat storage material 62 and the four-way valve 25 in the first pipe 51 and returns to the compressor 23. At this time, the refrigerant is heated in the heat storage material 62 and vaporized.

During heating operation, the control device 14 controls the expansion valve 31 so that the temperature detected by the temperature sensor 71B is 4°C more than the temperature detected by the temperature sensor 71A (outdoor air temperature).

Figure 4 is a Mollier diagram of the air conditioner 10 of the first embodiment. The Mollier diagram during the cooling operation and heating operation is as shown in Figure 4. Points P1 to P6 in Figure 4 correspond to points P1 to P6 in Figures 1 and 2. As shown in Figure 4, in this embodiment, the refrigerant is cooled between points P3 and P4, and the enthalpy decreases. Specifically, for example, at point P3, the refrigerant is partially liquefied by reducing the pressure by the expansion valve 31, and is in a two-phase gas-liquid state with 80% liquid and 20% gas. This refrigerant is passed through the heat storage material 63 and cooled by the heat storage material 63 to reduce the enthalpy and reach the state of point P4. The state of the refrigerant at point P4 is 100% liquid.

During the above cooling and heating operations, the heat storage material 63 is pre-cooled by the cold storage operation described below.

Figure 5 is a refrigerant system diagram that shows the air conditioner 10 during the heat storage operation of the first embodiment. As shown in Figure 5, in the cold storage operation, each part is controlled so that the refrigerant flows basically in the same way as in the heating operation. However, the first on-off valve 34 is closed, and the second on-off valve 35 is opened. In addition, in the cold storage operation, the first on-off valve 34 is controlled so that the refrigerant discharged from the second three-way valve 33 flows into the third pipe 53. That is, in the cold storage operation, the refrigerant discharged from the compressor 23 passes through the area 51a of the first pipe 51, the indoor heat exchanger 41, the area 52b of the second pipe 52, the first three-way valve 32, the expansion valve 31, the second three-way valve 33, the third pipe 53, and the area 52a of the second pipe 52, and enters the outdoor heat exchanger 21. At this time, the refrigerant cools the heat storage material 63. That is, the temperature of the heat storage material 63 decreases. The refrigerant leaving the outdoor heat exchanger 21 returns to the compressor 23 through the region 51d of the first pipe 51. At this time, the refrigerant heats the heat storage material 62. That is, the temperature of the heat storage material 62 rises. The heat storage operation continues until the temperature of the heat storage material 63 becomes the outside air temperature minus 4°C. This is achieved, for example, by performing cold storage operation for one hour. With this cold storage, the refrigerant can be cooled for eight hours, for example, during cooling operation or heating operation. At this time, for example, at point P2, the refrigerant liquid is at a medium temperature (around 40°C), and at point P3 after passing through the expansion valve 31, the refrigerant liquid is at a low temperature.

Figure 6 is a flowchart showing an example of cold storage operation control of the air conditioner 10 of this embodiment. The control device 14 of this embodiment executes the cold storage operation, for example, when no human is present in the room. Note that the time when the cold storage operation is executed is not limited to this example. For example, the cold storage operation may be executed when no human is present in the room and a predetermined start operation is received from a device such as a smartphone outside the room.

First, the operation switching unit 92 determines whether the start conditions for the cold storage operation are met (S11). For example, the operation switching unit 92 determines whether the room is unoccupied based on the output signal of the human presence sensor 72 provided in the indoor unit 12. If the operation switching unit 92 determines that the room has been unoccupied for a predetermined period of time, it determines that the start conditions for the cold storage operation are met.

If the start conditions for cold storage operation are not met (S11: No), the operation switching unit 92 waits without starting the cold storage operation. If the start conditions for cold storage operation are met (S11: Yes), the operation switching unit 92 starts the cold storage operation (S12).

The operation switching unit 92 determines whether the temperature detected by the temperature sensor 71H has reached a specified temperature (e.g., the outside air temperature minus 4°C) (S13). In S13, if the operation switching unit 92 determines that the specified temperature has been reached (S13: Yes), it ends the cold storage operation (S14). If the operation switching unit 92 determines that the specified temperature has not been reached (S13: No), it proceeds to S15.

In S15, the operation switching unit 92 determines whether or not to stop the cold storage operation. The conditions for stopping the cold storage operation (S15: Yes) or not (S15: No) are the same as the conditions for starting the cold storage operation. That is, if a person is present in the room, the cold storage operation is stopped, and if no person is present in the room, the cold storage operation is not stopped.

The control device 14 may also perform the cold storage operation, for example, when there are no animals in the room. In this case, the above process is performed with humans replaced with animals.

As described above, in this embodiment, the air conditioner 10 includes the indoor heat exchanger 41, the outdoor heat exchanger 21, the first pipe 51, the second pipe 52, the compressor 23, the four-way valve 25, the expansion valve 31, the first three-way valve 32, the third pipe 53, the first on-off valve 34, the heat storage material 63, the fourth pipe 54, the second on-off valve 35, and the control device 14. The first pipe 51 connects the indoor heat exchanger 41 and the outdoor heat exchanger 21, and the refrigerant flows through it. The second pipe 52 connects the outdoor heat exchanger 21 and the indoor heat exchanger 41, and the refrigerant flows through it. The compressor 23 is provided in the first pipe 51 and has an inlet 23a for sucking in the refrigerant and an outlet 23b for discharging the refrigerant. The four-way valve 25 is provided in the first pipe 51 and can change the direction of the refrigerant flow. The expansion valve 31 is provided in the second pipe 52. The first three-way valve 32 is provided in the second pipe 52 between the indoor heat exchanger 41 and the expansion valve 31 and can change the direction of the refrigerant flow. The third pipe 53 has one end 53a connected to the first three-way valve 32 and the other end 53b connected to the second pipe 52 between the outdoor heat exchanger 21 and the expansion valve 31, and can allow the refrigerant to flow. The first opening and closing valve 34 is provided in the third pipe 53. The heat storage material 63 is thermally connected to the second pipe 52 between the outdoor heat exchanger 21 and the expansion valve 31, and is thermally connected to the third pipe 53 between one end 53a of the third pipe 53 and the first opening and closing valve 34. The fourth pipe 54 has one end 54a connected to the third pipe 53 between the first on-off valve 34 and the heat storage material 63, and the other end 54b connected to the second pipe 52 between the indoor heat exchanger 41 and the first three-way valve 32. The second on-off valve 35 is provided in the fourth pipe 54. The control device 14 controls the four-way valve 25, the expansion valve 31, the first three-way valve 32, the first on-off valve 34, and the second on-off valve 35.

According to this configuration, for example, the refrigerant is caused to flow from the outdoor heat exchanger 21 to the indoor heat exchanger 41 through the first pipe 51, and then from the indoor heat exchanger 41 to the outdoor heat exchanger 21 through the second pipe 52 and the third pipe 53, thereby cooling the heat storage material 63. By performing cooling operation after cooling the heat storage material 63, the refrigerant that has been liquefied by being cooled by the heat storage material 63 during cooling operation can be fed into the indoor heat exchanger 41. Thus, the heat exchange efficiency of the indoor heat exchanger 41 can be prevented from decreasing. In other words, the heat exchange efficiency of the indoor heat exchanger 41 can be improved. In addition, by performing heating operation after cooling the heat storage material 63, the refrigerant that has been liquefied by being cooled by the heat storage material 63 during heating operation can be fed into the outdoor heat exchanger 21. Thus, the heat exchange efficiency of the outdoor heat exchanger 21 can be prevented from decreasing. In other words, the heat exchange efficiency of the outdoor heat exchanger 21 can be improved.

Here, for example, during cooling operation, the refrigerant enters the indoor heat exchanger 41 through the diverter 36. However, if the refrigerant entering the diverter 36 is in two phases, gas and liquid, the refrigerant may not be distributed evenly by the diverter 36. In contrast, in this embodiment, during cooling operation, liquid refrigerant enters the diverter 36, so the refrigerant is more likely to be distributed evenly by the diverter 36. In addition, since liquid refrigerant enters the diverter 36, the refrigerant is more likely to be distributed evenly even if the flow path in the diverter 36 is bent. In other words, the diverter 36 can precisely control the division of the refrigerant into the multiple refrigerant flow paths of the indoor heat exchanger 41. The diverter 36 may be provided in the outdoor heat exchanger 21.

In addition, during cooling operation, the refrigerant is cooled by the outdoor heat exchanger 21, and then further cooled by the heat storage material 63, so that gaseous refrigerant is prevented from remaining. This increases the enthalpy difference of the refrigerant, improving the cooling capacity and ultimately enabling the air conditioner 10 to save energy.

During heating operation, heat is exchanged between the refrigerant in region 51a and the refrigerant in region 51d in the heat storage material 62, and the refrigerant in region 51d is heated and vaporized, increasing its pressure. The vaporized and pressurized refrigerant in region 51d then enters the compressor 23. This reduces the workload of the compressor 23, thereby enabling the air conditioner 10 to save energy.

The air conditioner 10 also includes a second three-way valve 33 and a fifth pipe 55. The second three-way valve 33 is provided in the second pipe 52 between the expansion valve 31 and the heat storage material 63, and is capable of changing the direction in which the refrigerant flows. The fifth pipe 55 is connected to the third pipe 53 between the first three-way valve 32 and the heat storage material 63, and to the second three-way valve 33. The amount of heat that can be transferred per unit time between the third pipe 53 and the heat storage material 63 is greater than the amount of heat that can be transferred per unit time between the second pipe 52 and the heat storage material 63. The control device 14 controls the second three-way valve 33.

With this configuration, for example, when cooling the heat storage material 63, the refrigerant flows from the outdoor heat exchanger 21 to the indoor heat exchanger 41 via the first pipe 51, and then flows from the indoor heat exchanger 41 to the outdoor heat exchanger 21 via the second pipe 52 and the third pipe 53, so that the heat storage material 63 can be cooled in a relatively short time. On the other hand, during heating operation, the refrigerant flows from the outdoor heat exchanger 21 to the indoor heat exchanger 41 via the first pipe 51, and then flows from the indoor heat exchanger 41 to the outdoor heat exchanger 21 via the second pipe 52 without passing through the third pipe 53, so that the refrigerant can be cooled by the heat storage material 63 for a relatively long time.

The air conditioner 10 also includes a heat storage material 62 (heat exchanger). The heat storage material 62 exchanges heat between the first pipe 51 between the indoor heat exchanger 41 and the four-way valve 25 and the first pipe 51 between the outdoor heat exchanger 21 and the four-way valve 25.

With this configuration, the medium before flowing into the compressor 23 can be heated and vaporized by the heat storage material 62. This makes it possible to suppress the occurrence of so-called liquid backflow, in which liquid refrigerant enters the compressor 23.

The air conditioner 10 also includes a human presence sensor 72 (detection sensor). The human presence sensor 72 detects a human or animal in the room in which the indoor heat exchanger 41 is installed. When the human presence sensor 72 does not detect a human or animal, the control device 14 performs a cold storage operation to cool the heat storage material 63.

With this configuration, the cold storage operation is performed, for example, when no one is in the room, so people are less likely to notice that the cold storage operation is being performed.

In addition, the control device 14 stops the cold storage operation if the human presence sensor 72 detects a human or animal.

With this configuration, when the human presence sensor 72 detects a human or animal, the cold storage operation is stopped and the indoor heat exchanger 41 stops heating the room, thereby reducing human discomfort, for example in the summer.

Second Embodiment
7 is a refrigerant system diagram that shows the air conditioner 10 in cooling operation according to the second embodiment. In this embodiment, the flow of the refrigerant in cooling operation is different from that in the first embodiment. Specifically, when the cold storage degree, which is the degree of cold storage in the heat storage material 63, reaches a specified degree (also referred to as a specified degree), the control device 14 controls the first three-way valve 32 so that the refrigerant flows through the third pipe 53 in cooling operation (FIG. 1). On the other hand, when the cold storage degree of the heat storage material 63 does not reach the specified degree, the control device 14 controls the first three-way valve 32 so that the refrigerant does not flow through the third pipe 53 in cooling operation (FIG. 7).

Figure 8 is a flowchart showing an example of cooling operation control of the air conditioner 10 of the second embodiment. As shown in Figure 8, the control device 14 judges whether the cold storage degree of the heat storage material 63 has reached a specified degree (S21). For example, the control device 14 judges that the cold storage degree of the heat storage material 63 has reached the specified degree when the temperature detected by the temperature sensor 71H is equal to or higher than a specified temperature (for example, a temperature in a specified range including a value obtained by subtracting 4°C from the outside air temperature) or when the heat storage operation before the cooling operation has been performed for one hour or more. On the other hand, the control device 14 judges that the cold storage degree of the heat storage material 63 has not reached the specified degree when the temperature detected by the temperature sensor 71H is equal to or lower than the specified temperature or when the heat storage operation before the cooling operation has been performed for less than one hour. The cooling degree corresponds to the cold storage amount.

When the control device 14 determines that the degree of cold storage in the heat storage material 63 has reached a specified degree (S21: Yes), it controls the first three-way valve 32 so that the refrigerant flows through the third pipe 53 (S22, FIG. 1). On the other hand, when the degree of cold storage in the heat storage material 63 has not reached a specified degree, the control device 14 controls the first three-way valve 32 so that the refrigerant does not flow through the third pipe 53 (S23, FIG. 7).

As described above, in this embodiment, when the degree of cold storage of the heat storage material 63, that is, the degree of cold storage, reaches a specified degree, the control device 14 controls the first three-way valve 32 so that the refrigerant flows through the third pipe 53 during cooling operation, and when the degree of cold storage of the heat storage material 63 does not reach the specified degree, the control device 14 controls the first three-way valve 32 so that the refrigerant does not flow through the third pipe 53 during cooling operation.

With this configuration, if the degree of cold storage in the heat storage material 63 does not reach a specified level, the refrigerant does not flow into the third pipe 53, simplifying the refrigerant path and reducing pressure loss.

Figure 9 is a block diagram showing an example of the hardware configuration of the control device 14 in the first and second embodiments. The control device 14 is realized, for example, by a computer 100 having a hardware configuration as shown in Figure 9.

The computer 100 has, for example, a CPU 101, a ROM 102, a RAM 103, a storage device 104, and an interface (I/F) 106. The CPU 101, the ROM 102, the RAM 103, the storage device 104, and the I/F 106 are connected by a bus.

The CPU 101 loads the programs stored in the storage device 104 into the RAM 103 and executes them, and can control each part to perform input/output and data processing. The ROM 102 stores a start program that reads the operating system startup program from the storage device 104 to the RAM 103.

The storage device 104 is, for example, a flash memory. The storage device 104 stores an operating system, application programs, and data. These programs are distributed in the form of installable or executable files recorded on a computer-readable recording medium. The programs may also be distributed by downloading them from a server.

The I/F 106 is an interface device for connecting to, for example, the temperature sensors 71A to 71J, the human presence sensor 72, the outdoor fan drive circuit 81, the indoor fan drive circuit 82, the inverter circuit 83, the four-way valve drive circuit 84, the expansion valve drive circuit 85, the first three-way valve drive circuit 86, the second three-way valve drive circuit 87, the first on-off valve drive circuit 88, and the second on-off valve drive circuit 89.

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

The program executed by the computer 100 of this embodiment may be configured to be stored on a computer connected to a network such as the Internet and provided by downloading it via the network. The program executed by the computer 100 of this embodiment may be configured to be provided or distributed via a network such as the Internet. The program of this embodiment may be configured to be provided by being pre-installed in the ROM 102, etc.

The program for making the computer 100 function as the control device 14 has a modular configuration 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. In the computer 100, the processor (CPU 101) reads out and executes the program from a storage medium (such as the storage device 104) as actual hardware, and each module is loaded onto the main storage device (RAM 103). As a result, the processor (CPU 101) functions as 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 in FIG. 3. Note that the computer 100 may have some or all of the configurations 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 realized by hardware.

In the above embodiment, the heat exchanger is an example of heat storage material 62, but this is not limited to this. For example, the heat exchanger may be a double pipe.

In addition, during cold storage operation, the refrigerant that has passed through the expansion valve 31 may be circulated to the outdoor heat exchanger 21 via the second pipe 52, rather than through the third pipe 53. In this case, for example, the second three-way valve 33 and the fifth pipe 55 may not be provided.

Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the scope of the invention and its equivalents described in the claims.

10...air conditioner, 14...control device, 21...outdoor heat exchanger, 23...compressor, 23a...suction port, 23b...discharge port, 25...four-way valve, 31...expansion valve, 32...first three-way valve, 33...second three-way valve, 34...first on-off valve, 35...second on-off valve, 41...indoor heat exchanger, 51...first pipe, 52...second pipe, 53...third pipe, 53a...one end, 53b...other end, 54...fourth pipe, 54a...one end, 54b...other end, 55...fifth pipe, 62...heat storage material (heat exchanger), 63...heat storage material, 72...human presence sensor (detection sensor).

Claims (6)

An indoor heat exchanger;
An outdoor heat exchanger;
a first pipe connecting the indoor heat exchanger and the outdoor heat exchanger and through which a refrigerant flows;
a second pipe connecting the outdoor heat exchanger and the indoor heat exchanger and through which the refrigerant flows;
a compressor provided in the first pipe, the compressor having an intake port for sucking the refrigerant and an exhaust port for exhausting the refrigerant;
a four-way valve provided in the first pipe and capable of changing a flow direction of the refrigerant;
an expansion valve provided in the second pipe;
a first three-way valve provided in the second pipe between the indoor heat exchanger and the expansion valve and capable of changing a flow direction of the refrigerant;
a third pipe having one end connected to the first three-way valve and the other end connected to the second pipe between the outdoor heat exchanger and the expansion valve, through which the refrigerant can flow;
a first on-off valve provided in the third pipe;
a heat storage material that is thermally connected to the second pipe between the outdoor heat exchanger and the expansion valve and is thermally connected to the third pipe between the one end of the third pipe and the first on-off valve;
a fourth pipe having one end connected to the third pipe between the first on-off valve and the heat storage material, and the other end connected to the second pipe between the indoor heat exchanger and the first three-way valve;
a second on-off valve provided in the fourth pipe;
a control device that controls the four-way valve, the expansion valve, the first three-way valve, the first on-off valve, and the second on-off valve;
An air conditioner equipped with: a second three-way valve provided in the second pipe between the expansion valve and the heat storage material and capable of changing a flow direction of the refrigerant;
a fifth pipe connected to the third pipe between the first three-way valve and the heat storage material and to the second three-way valve;
Equipped with
an amount of heat transferable per unit time between the third pipe and the heat storage material is greater than an amount of heat transferable per unit time between the second pipe and the heat storage material;
The air conditioner according to claim 1 , wherein the control device controls the second three-way valve. a heat exchanger that exchanges heat between the first pipe between the indoor heat exchanger and the four-way valve and the first pipe between the outdoor heat exchanger and the four-way valve;
The air conditioner according to claim 1 or 2, comprising: a detection sensor for detecting a human or an animal in the room in which the indoor heat exchanger is installed;
4. The air conditioner according to claim 1, wherein the control device performs a cold storage operation for cooling the heat storage material when the detection sensor does not detect the human or the animal. The air conditioner according to claim 4, wherein the control device stops the cold storage operation when the detection sensor detects the human or the animal. The air conditioner according to any one of claims 1 to 5, wherein the control device controls the first three-way valve so that refrigerant flows through the third pipe during cooling operation when the degree of cold storage of the heat storage material reaches a specified degree, and controls the first three-way valve so that refrigerant does not flow through the third pipe during cooling operation when the degree of cold storage of the heat storage material does not reach the specified degree.

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