JP2024080933A - Air Conditioning Equipment - Google Patents

Abstract

[Problem] To provide an air conditioner equipped with a refrigeration cycle that allows the size of a heat exchanger to be reduced. [Solution] The air conditioner includes an indoor heat exchanger, an outdoor heat exchanger, a first pipe, a second pipe, a compressor, a first four-way valve, an ejector, a second four-way valve, a gas-liquid separator, a third pipe, a fourth pipe, and a fifth pipe. 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 a refrigerant flows through it. The third pipe connects the first pipe that connects the first four-way valve and the suction port of the compressor, and a second inlet of the ejector. The fourth pipe connects the first pipe that connects the first four-way valve and the indoor heat exchanger, and a second pipe that connects the first inlet of the ejector and the second four-way valve. The fifth pipe connects the third opening of the gas-liquid separator to the third pipe or the second pipe connecting the first inlet of the ejector to the second four-way valve. [Selected Figure]

Description

An embodiment of the present invention relates to an air conditioning device.

Air conditioning devices such as air conditioners regulate the indoor temperature by condensing and evaporating the refrigerant in a refrigeration cycle. During heating operation, the refrigerant evaporates in the outdoor heat exchanger (evaporator) and condenses in the indoor heat exchanger (condenser). During cooling operation, the refrigerant condenses in the outdoor heat exchanger (condenser) and evaporates in the indoor heat exchanger (evaporator).

JP 2008-116124 A

In recent years, there has been a demand for air conditioners that can be made smaller and also contribute to energy conservation.

One example of the problem that this invention solves is to provide an air conditioner equipped with a refrigeration cycle that allows the heat exchanger to be made smaller.

An air conditioning apparatus according to one embodiment of the present invention includes an indoor heat exchanger, an outdoor heat exchanger, a first pipe, a second pipe, a compressor, a first four-way valve, an ejector, a second four-way valve, a gas-liquid separator, a third pipe, a fourth pipe, and a fifth pipe. The indoor heat exchanger is provided in an indoor unit. The outdoor heat exchanger is provided in an outdoor unit. The first pipe connects the indoor heat exchanger and the outdoor heat exchanger, and a refrigerant flows through the first pipe. The second pipe connects the outdoor heat exchanger and the indoor heat exchanger, and the refrigerant flows through the second pipe. The compressor is provided in the first pipe and has an intake port for sucking in the refrigerant and an exhaust port for discharging the refrigerant. The first four-way valve is provided in the first pipe and is capable of changing the direction in which the refrigerant flows. The ejector is provided in the second pipe and has a first inlet through which the refrigerant flows in from the upstream side of the second pipe and a second inlet through which the refrigerant flows in from a pipe different from the second pipe, and is capable of mixing the refrigerant supplied to the first inlet and the refrigerant supplied to the second inlet and supplying the refrigerant from an outlet to the downstream side of the second pipe. The second four-way valve is provided in the second pipe and is connected to the first inlet and the outlet of the ejector and is capable of changing the flow direction of the refrigerant flowing out from the outlet. The gas-liquid separator is provided in the second pipe and has a first opening connected to the second four-way valve, a second opening connected to the outdoor heat exchanger, and a third opening through which the gaseous refrigerant passes. The third pipe connects the first pipe connecting the first four-way valve and the suction port of the compressor to the second inlet of the ejector. The fourth pipe connects the first pipe connecting the first four-way valve and the indoor heat exchanger to the second pipe connecting the first inlet of the ejector and the second four-way valve. The fifth pipe connects the third opening of the gas-liquid separator to the third pipe or the second pipe connecting the first inlet of the ejector and the second four-way valve.

The air conditioning device may also include, for example, a first flow control valve in the third pipe that controls the flow rate of the refrigerant.

The air conditioning device may also include, for example, a second flow control valve in the fourth pipe that controls the flow rate of the refrigerant.

The above air conditioning system can, for example, improve the heat exchange efficiency in the refrigeration cycle, and provide an air conditioning system that allows the heat exchanger to be made smaller.

FIG. 1 is a refrigerant system diagram of an air-conditioning apparatus according to an embodiment, and is also an exemplary and schematic diagram showing the flow of refrigerant during cooling operation. FIG. 2 is an exemplary schematic cross-sectional view illustrating the configuration of an ejector mounted in the outdoor unit of the air conditioner according to the embodiment. FIG. 3 is an exemplary schematic block diagram showing a control device for an air-conditioning device according to the embodiment and a configuration controlled by the control device. FIG. 4 is a refrigerant system diagram of the air conditioner according to the embodiment, and is also an exemplary schematic diagram showing the flow of refrigerant during heating operation.

Below, several embodiments are described with reference to Figs. 1 to 4. Note that in this specification, components according to the embodiments and descriptions of the components may be described in multiple ways. The components and their descriptions are merely examples and are not limited by the expressions in this specification. The components may also 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 an exemplary schematic diagram showing a refrigerant system diagram of an air conditioning device 10 according to an embodiment. The air conditioning device 10 is, for example, a home air conditioner. Note that the air conditioning device 10 is not limited to this example and may be another air conditioning device such as a commercial air conditioner.

As shown in FIG. 1, the air conditioning device 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 conditioning device 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, for example, by electrical wiring.

The outdoor unit 11 has an outdoor heat exchanger 21, an outdoor blower fan 22, a compressor 23, an accumulator 24, a first four-way valve 25, a second four-way valve 26, an ejector 27, a first flow control valve 31, a second flow control valve 32, a three-way valve 33 (switching valve), a gas-liquid separator 61, etc. 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 includes a first pipe 51, a second pipe 52, a third pipe 53, a fourth pipe 54, a fifth pipe 55, etc.

The first pipe 51 connects the indoor heat exchanger 41 and the outdoor heat exchanger 21. The compressor 23, the accumulator 24, and the first four-way valve 25 are provided in the first pipe 51. The first pipe 51 has a first region 51a, a second region 51b, a third region 51c, and a fourth region 51d. The first region 51a is a pipe region that connects the first four-way valve 25 and the indoor heat exchanger 41. The second region 51b is a pipe region that connects the first four-way valve 25 and the accumulator 24. The third region 51c is a pipe region that connects the first four-way valve 25 and the outdoor heat exchanger 21. The fourth region 51d is a pipe region that connects the first four-way valve 25 and the discharge port 23b of the compressor 23.

The second piping 52 connects the outdoor heat exchanger 21 and the indoor heat exchanger 41. The second four-way valve 26, the ejector 27, and the gas-liquid separator 61 are provided in the second piping 52. The second piping 52 has a fifth region 52a, a sixth region 52b, a seventh region 52c, an eighth region 52d, and a ninth region 52e. The fifth region 52a is a piping region that connects the second four-way valve 26 and the indoor heat exchanger 41. The sixth region 52b is a piping region that connects the second four-way valve 26 and the outlet 73 of the ejector 27. The seventh region 52c is a piping region that connects the second four-way valve 26 and the first opening 61a of the gas-liquid separator 61. The eighth region 52d is a piping region that connects the second opening 61b of the gas-liquid separator 61 and the outdoor heat exchanger 21. The ninth region 52e is a piping region that connects the second four-way valve 26 and the first inlet 71 of the ejector 27.

The third pipe 53 connects the first pipe 51, which connects the first four-way valve 25 and the suction port 23a of the compressor 23, to the second inlet 72 of the ejector 27. The first flow control valve 31 is provided in the third pipe 53. The third pipe 53 has a tenth region 53a and an eleventh region 53b. The tenth region 53a is a pipe region that connects the second inlet 72 of the ejector 27 and the first flow control valve 31. The eleventh region 53b is a pipe region that connects the second region 51b of the first pipe 51 and the first flow control valve 31. The third pipe 53 is a pipe for supplying a low-pressure refrigerant, which is pressurized by the driving refrigerant flowing in from the first inlet 71 of the ejector 27, from the second inlet 72.

The fourth pipe 54 connects the first pipe 51 connecting the first four-way valve 25 and the indoor heat exchanger 41, and the second pipe 52 connecting the first inlet 71 of the ejector 27 and the second four-way valve 26. The second flow control valve 32 is provided in the fourth pipe 54. The fourth pipe 54 has a twelfth region 54a and a thirteenth region 54b. The twelfth region 54a is a pipe region connecting the first region 51a of the first pipe 51 and the second flow control valve 32. The thirteenth region 54b is a pipe region connecting the second flow control valve 32 and the ninth region 52e of the second pipe 52. The fourth pipe 54 is a pipe for supplying a portion of the high-temperature, high-pressure refrigerant from the compressor 23 as a driving refrigerant to boost the low-pressure refrigerant supplied from the second inlet 72 of the ejector 27 during heating operation.

The fifth pipe 55 connects the third opening 61c of the gas-liquid separator 61 to the second pipe 52 that connects the tenth region 53a of the third pipe 53 or the first inlet 71 of the ejector 27 to the second four-way valve 26. The three-way valve 33 is provided in the fifth pipe 55. The fifth pipe 55 has a fourteenth region 55a, a fifteenth region 55b, and a sixteenth region 55c. The fourteenth region 55a is a pipe region that connects the third opening 61c of the gas-liquid separator 61 to the three-way valve 33. The fifteenth region 55b is a pipe region that connects the three-way valve 33 to the ninth region 52e of the second pipe 52. The sixteenth region 55c is a pipe region that connects the three-way valve 33 to the tenth region 53a of the third pipe 53. The fifth pipe 55 is a pipe for supplying the gaseous refrigerant separated in the gas-liquid separator 61 to the first inlet 71 of the ejector 27 as the driving refrigerant during cooling operation, and to the second inlet 72 of the ejector 27 as the suction refrigerant during heating operation.

As shown in FIG. 1, 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. Also, as shown in FIG. 4, in 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.

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 to 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 can also function as the suction port of the compressor 23 by being configured integrally with the compressor 23.

The first 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 first flow control valve 31. The first 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 first flow control valve 31 during heating operation and cooling operation, changing the direction in which the refrigerant flows.

During cooling operation, the first four-way valve 25 connects the discharge port 23b of the compressor 23 to the outdoor heat exchanger 21 and supplies high-temperature, high-pressure gaseous refrigerant to the outdoor heat exchanger 21. Furthermore, during cooling operation, the first four-way valve 25 connects the indoor heat exchanger 41 to the accumulator 24 and returns the low-temperature, low-pressure gaseous refrigerant to the accumulator 24. As a result, the refrigerant compressed by the compressor 23 flows to the outdoor heat exchanger 21, and the refrigerant that has been heat exchanged (evaporated) in the indoor heat exchanger 41 flows to the accumulator 24. Note that, during cooling operation, the refrigerant discharged from the indoor heat exchanger 41 includes gaseous refrigerant that returns to the accumulator 24 (compressor 23) and refrigerant that is supplied as suction refrigerant to the second inlet 72 of the ejector 27 without returning to the accumulator 24 (compressor 23). Details of the ejector 27 will be described later.

During heating operation, as shown in FIG. 4, the first four-way valve 25 connects the discharge port 23b of the compressor 23 to the indoor heat exchanger 41, and supplies high-temperature, high-pressure gaseous refrigerant to the indoor heat exchanger 41. During heating operation, the first four-way valve 25 connects the outdoor heat exchanger 21 to the accumulator 24, and provides low-temperature, low-pressure gaseous refrigerant to the accumulator 24. As a result, the refrigerant compressed by the compressor 23 flows to the indoor heat exchanger 41, and the refrigerant that has undergone heat exchange (evaporated) in the outdoor heat exchanger 21 flows to the accumulator 24.

The second four-way valve 26 is connected to the indoor heat exchanger 41, the outlet 73 of the ejector 27, the first opening 61a of the gas-liquid separator 61, and the ninth region 52e of the second pipe 52. The second four-way valve 26 switches the flow paths connected to the indoor heat exchanger 41, the outlet 73 of the ejector 27, the first opening 61a of the gas-liquid separator 61, and the ninth region 52e of the second pipe 52 during heating operation and cooling operation, and changes the direction of the refrigerant flow. The second four-way valve 26 is not limited to a general four-way valve, and may be a valve of other configurations as long as it can change the direction of the refrigerant flow. For example, it may be replaced with a bridge circuit in which four check valves are connected in a ring shape. If a bridge circuit is adopted as the second four-way valve, the second four-way valve drive circuit can be omitted.

During cooling operation, as shown in FIG. 1, the second four-way valve 26 connects the first opening 61a of the gas-liquid separator 61 to the first inlet 71 of the ejector 27, and supplies the liquid refrigerant separated in the gas-liquid separator 61 (the liquid refrigerant heat-exchanged (condensed) in the outdoor heat exchanger 21) to the first inlet 71 of the ejector 27. The first inlet 71 is also supplied with the gas-liquid refrigerant separated in the gas-liquid separator 61. In other words, the first inlet 71 is supplied with a two-phase gas-liquid refrigerant as the driving refrigerant. Therefore, during cooling operation, the function of the gas-liquid separator 61 is not substantially utilized, and when the air conditioning device 10 is configured for cooling operation only, the gas-liquid separator 61 can be omitted. During cooling operation, the second four-way valve 26 flows the refrigerant discharged from the outlet 73 of the ejector 27 to the second piping. The refrigerant discharged from the outlet 73 is a low-temperature, low-pressure refrigerant (suction refrigerant) discharged from the indoor heat exchanger 41 and supplied to the ejector 27 without returning to the accumulator 24 (compressor 23), and is mixed with a gas-liquid two-phase refrigerant (driving refrigerant) supplied from the outdoor heat exchanger 21 side and pressurized. As a result, as described above, it is possible to flow low-temperature refrigerant to the indoor heat exchanger 41 without passing through the compressor 23.

During heating operation, as shown in FIG. 4, the second four-way valve 26 connects the indoor heat exchanger 41 to the first inlet 71 of the ejector 27, and provides the liquid refrigerant discharged from the indoor heat exchanger 41 to the first inlet 71. The first inlet 71 is also supplied with a portion of the high-temperature, high-pressure refrigerant discharged from the compressor 23. The second four-way valve 26 also connects the outlet 73 of the ejector 27 to the first opening 61a of the gas-liquid separator 61, and supplies the refrigerant flowing out from the outlet 73 to the gas-liquid separator 61 and returns it to the accumulator 24.

The ejector 27 is provided in the second pipe 52. More specifically, the ejector 27 has a first inlet 71, a second inlet 72, and an outlet 73. The first inlet 71 receives refrigerant from the upstream side of the second pipe 52 in the direction of refrigerant flow during cooling operation and heating operation. The second inlet 72 receives refrigerant from a pipe (the third pipe 53 or the fifth pipe 55) different from the second pipe 52. The outlet 73 mixes the refrigerant supplied to the first inlet 71 and the refrigerant supplied to the second inlet 72, and discharges (supplies) the pressurized refrigerant to the downstream side of the second pipe 52 in the direction of refrigerant flow during cooling operation and heating operation.

Figure 2 is an exemplary and schematic cross-sectional view showing the structure of the ejector 27 of this embodiment. As shown in Figure 2, the ejector 27 has a simple structure, and is therefore easy to maintain and to install in the air conditioning device 10. Note that the structure of the ejector 27 is not limited to the example shown in Figure 2. The ejector 27 is provided with a first inlet 71, a second inlet 72, an outlet 73, a nozzle section 74, a suction section 75, a mixing section 76, and a diffuser section 77.

As shown in FIG. 1, the first inlet 71 is connected to the second four-way valve 26 via the ninth region 52e of the second pipe 52. For example, during cooling operation, refrigerant flows in from the outdoor heat exchanger 21 side. During heating operation, refrigerant flows in from the indoor heat exchanger 41 side.

The second inlet 72 is connected to the tenth region 53a of the third pipe 53. For example, during cooling operation, a portion of the gaseous refrigerant discharged from the indoor heat exchanger 41 flows into the second inlet 72 via the first flow control valve 31. During heating operation, a portion of the gaseous refrigerant discharged from the outdoor heat exchanger 21, separated by the gas-liquid separator 61, and passed through the three-way valve 33 flows into the second inlet 72. The outlet 73 discharges the pressurized gas-liquid two-phase refrigerant to the second four-way valve 26 via the sixth region 52b of the second pipe 52.

As described above, the ejector 27 can mix the refrigerant (driving refrigerant) supplied to the first inlet 71 with the refrigerant (suction refrigerant) supplied to the second inlet 72, increase the pressure of the refrigerant, and release it from the outlet 73. Therefore, the ejector 27 supplies low-temperature, low-pressure refrigerant from the outlet 73 through the second piping 52 to the indoor heat exchanger 41, which functions as an evaporator during cooling operation, and to the outdoor heat exchanger 21, which functions as an evaporator during heating operation.

As shown in FIG. 2, the nozzle portion 74 is provided between the first inlet 71 and the mixing portion 76. The nozzle portion 74 is a flow path having a portion that tapers toward the mixing portion 76 and a portion that gradually expands. The shape of the nozzle portion 74 is not limited to this, and any structure may be used as long as the refrigerant that has flowed in can be decompressed and sprayed at high speed. The nozzle portion 74 decompresses and expands the refrigerant that has flowed into the first inlet 71, and sprays it into the mixing portion 76. Since the pressure near the outlet of the nozzle portion 74 is low, the first inlet 71 connected to the nozzle portion 74 can suck in the refrigerant.

The suction section 75 is provided between the second inlet 72 and the mixing section 76. The suction section 75 is provided around the nozzle section 74 and is a substantially cylindrical flow path having a portion tapering toward the mixing section 76. The suction section 75 reduces the pressure of the refrigerant that has flowed into the second inlet 72 and expands it, causing it to be ejected into the mixing section 76. Since the pressure near the outlet of the suction section 75 is low, the second inlet 72 connected to the suction section 75 can suck in the refrigerant.

The mixing section 76 is provided between the nozzle section 74 and the suction section 75 and the diffuser section 77. In the mixing section 76, the ejector 27 mixes the refrigerant ejected from the suction section 75 with the refrigerant ejected from the nozzle section 74.

The diffuser section 77 is provided between the mixing section 76 and the outlet 73. The diffuser section 77 is a flow path having a portion that expands toward the outlet 73. The refrigerant mixed in the mixing section 76 is decelerated and pressurized in the diffuser section 77, and is released from the outlet 73.

The ejector 27 has an ejector solenoid valve 78. The ejector solenoid valve 78 can open and close the first inlet 71. In FIG. 2, the ejector solenoid valve 78 is shown to be located outside the nozzle portion 74, but the ejector solenoid valve 78 may be provided inside the nozzle portion 74 or in another portion. For example, it may be a needle-shaped valve that is inserted into the nozzle portion 74 to adjust the opening degree. The ejector solenoid valve 78 adjusts the amount of refrigerant supplied to the first inlet 71 by controlling the opening degree. In the ejector 27, the amount of refrigerant supplied to the second inlet 72 can be adjusted by the first flow control valve 31, but the ejector solenoid valve may be provided at or inside the second inlet 72, similar to the first inlet 71.

The first flow control valve 31 is provided in the third pipe 53. As described above, in the cooling operation, the refrigerant discharged from the indoor heat exchanger 41 includes a gaseous refrigerant that returns to the accumulator 24 (compressor 23) and a refrigerant that is supplied to the second inlet 72 of the ejector 27 as a suction refrigerant without returning to the accumulator 24 (compressor 23). The first flow control valve 31 is a control valve for suppressing (adjusting) the suction refrigerant from being sucked too much into the ejector 27 (second inlet 72). On the other hand, in the heating operation, the first flow control valve 31 is basically in a closed state to prevent the gaseous refrigerant separated by the gas-liquid separator 61 from returning to the accumulator 24. In other words, the first flow control valve 31 controls the flow rate so as to prevent the suction pressure of the suction refrigerant in the ejector 27 (second inlet 72) from decreasing. The first flow control valve 31 may be another type of control valve, such as an expansion valve, as long as it is capable of adjusting the flow rate of the refrigerant.

The second flow control valve 32 is provided in the fourth pipe 54. The second flow control valve 32 adjusts the inflow amount of the high-temperature, high-pressure gaseous refrigerant discharged from the compressor 23 into the first inlet 71 of the ejector 27 during heating operation. In other words, the second flow control valve 32 adjusts the opening to balance the flow rate so as to supply the driving refrigerant to the ejector 27 while suppressing a decrease in the amount of high-temperature, high-pressure gaseous refrigerant supplied to the indoor heat exchanger 41 and a decrease in heat exchange efficiency. In addition, during cooling operation, the second flow control valve 32 closes to prevent the gaseous refrigerant discharged from the indoor heat exchanger 41 from flowing into the first inlet 71 of the ejector 27. In other words, it functions as a valve that closes the fourth pipe 54.

The three-way valve 33 is provided in the fifth pipe 55. The three-way valve 33 switches the flow path of the gaseous refrigerant supplied from the third opening 61c of the gas-liquid separator 61 between cooling operation and heating operation. During cooling operation, the three-way valve 33 connects the 14th region 55a and the 15th region 55b of the fifth pipe 55 so as to supply the gaseous refrigerant supplied from the third opening 61c of the gas-liquid separator 61 to the first inlet 71 of the ejector 27. On the other hand, during cooling operation, the three-way valve 33 connects the 14th region 55a and the 16th region 55c of the fifth pipe 55 so as to supply the gaseous refrigerant supplied from the third opening 61c of the gas-liquid separator 61 to the second inlet 72 of the ejector 27. The three-way valve 33 may be another type of solenoid valve or the like as long as it can switch the flow path.

The gas-liquid separator 61 is provided in the second pipe 52. The gas-liquid separator 61 is, for example, a surface tension gas-liquid separator. The gas-liquid separator 61 may be another gas-liquid separator such as a receiver tank, as long as it can separate the refrigerant into a gaseous state and a liquid state. The gas-liquid separator 61 is provided with a first opening 61a (liquid refrigerant inlet/outlet), a second opening 61b (liquid refrigerant inlet/outlet), and a third opening 61c (gaseous refrigerant outlet).

During cooling operation, the first opening 61a supplies the liquid refrigerant separated in the gas-liquid separator 61 to the first inlet 71 of the ejector 27 via the second four-way valve 26. During heating operation, the first opening 61a supplies the gas-liquid two-phase refrigerant discharged from the outlet 73 of the ejector 27 via the second four-way valve 26.

The second opening 61b is where the refrigerant discharged from the outdoor heat exchanger 21 flows in during cooling operation. Also, the second opening 61b is where the liquid refrigerant separated in the gas-liquid separator 61 flows out toward the outdoor heat exchanger 21 during heating operation.

During cooling operation, the third opening 61c supplies the gaseous refrigerant separated by the gas-liquid separator 61 to the first inlet 71 of the ejector 27 via the three-way valve 33. During heating operation, the third opening 61c supplies the gaseous refrigerant separated by the gas-liquid separator 61 to the second inlet 72 of the ejector 27 via the three-way valve 33.

As described above, during cooling operation, the liquid refrigerant flowing out from the first opening 61a of the gas-liquid separator 61 and the gaseous refrigerant flowing out from the third opening 61c are both supplied to the first inlet 71 of the ejector 27. In other words, they are supplied to the ejector 27 in a two-phase gas-liquid state. Therefore, when the air conditioning device 10 is configured as a cooling-only machine, the gas-liquid separator 61 can be omitted, and the two-phase gas-liquid refrigerant discharged from the outdoor heat exchanger 21 can be directly supplied to the first inlet 71 of the ejector 27.

The control device 14 controls the outdoor blower fan 22, the indoor blower fan 42, the compressor 23, the valves, etc., which are provided in the outdoor unit 11 and the indoor unit 12, and performs cooling operation, heating operation, dehumidification operation, defrosting operation, and other operation control. The control device 14 is composed of, for example, an outdoor control device 14a provided in the outdoor unit 11 and an indoor control device 14b provided in the indoor unit 12. The outdoor control device 14a and the indoor control device 14b are electrically connected to each other and send and receive control signals to cooperate with each other to control the outdoor unit 11 and the indoor unit 12. The indoor control device 14b provided in the indoor unit 12 may be controlled by inputting a signal from a remote controller operated by a user, or may be controlled by inputting a signal from an information terminal such as a smartphone through a communication device. The outdoor control device 14a and the indoor control device 14b may be collectively referred to as one control device 14. In this case, the control device 14 may be provided in either the outdoor unit 11 or the indoor unit 12, but can be provided in the indoor unit 12, for example.

The control device 14 is, for example, a computer having a control device such as a CPU (Central Processing Unit) or a microcontroller, and a storage device such as a ROM (Read Only Memory), a RAM (Random Access Memory), and a flash memory. Note that the control device 14 is not limited to this example.

Figure 3 is an exemplary schematic block diagram showing the control device 14 of the air conditioning device 10 of this embodiment and the configuration controlled by the control device 14. As shown in Figure 3, the air conditioning device 10 of this embodiment has an outdoor fan drive circuit 81, an indoor fan drive circuit 82, an inverter circuit 83, a first four-way valve drive circuit 84, a second four-way valve drive circuit 85, a first flow control valve drive circuit 86, a second flow control valve drive circuit 87, a three-way valve drive circuit 88, an ejector solenoid valve drive circuit 89, and the like.

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 first four-way valve drive circuit 84 is a drive circuit for the first four-way valve 25. The second four-way valve drive circuit 85 is a drive circuit for the second four-way valve 26. The first flow control valve drive circuit 86 is a drive circuit for the first flow control valve 31. The second flow control valve drive circuit 87 is a drive circuit for the second flow control valve 32. The three-way valve drive circuit 88 is a drive circuit for the three-way valve 33. The ejector solenoid valve drive circuit 89 is a drive circuit for the ejector solenoid valve 78.

The control device 14 is connected to the temperature sensors T1 to T5, the temperature sensor Su, the outdoor fan drive circuit 81, the indoor fan drive circuit 82, the inverter circuit 83, the first four-way valve drive circuit 84, the second four-way valve drive circuit 85, the first flow control valve drive circuit 86, the second flow control valve drive circuit 87, the three-way valve drive circuit 88, and the ejector solenoid 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 T1 to T5 and the temperature sensor Su to measure the temperature of each part in the refrigeration cycle. For example, the temperature sensor T1 detects the temperature of the refrigerant inside the indoor heat exchanger 41 (T1 value). The temperature sensor T2 detects the temperature of the refrigerant near the indoor heat exchanger 41 between the indoor heat exchanger 41 and the second four-way valve 26 (T2 value). The temperature sensor T3 detects the temperature of the refrigerant inside the outdoor heat exchanger 21 (T3 value). The temperature sensor T4 detects the temperature of the refrigerant near the outdoor heat exchanger 21 between the outdoor heat exchanger 21 and the gas-liquid separator 61 (T4 value). The temperature sensor T5 detects the temperature of the refrigerant near the first flow control valve 31 between the first flow control valve 31 and the second inlet 72 of the ejector 27 in the third piping 53 (T5 value). The temperature sensor Su detects the temperature of the refrigerant at the refrigerant inlet of the accumulator (Su value).

The operation switching unit 92 switches between cooling operation, heating operation, dehumidification operation, defrosting operation, and other operations in the air conditioning device 10.

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 first four-way valve 25, the second four-way valve 26, the first flow control valve 31, the second flow control valve 32, the three-way valve 33, and the ejector solenoid valve 78. The valve control unit 96 controls the first four-way valve drive circuit 84 to drive the actuator of the first four-way valve 25 and change the direction in which the refrigerant flows through the first four-way valve 25. The valve control unit 96 controls the second four-way valve drive circuit 85 to drive the actuator of the second four-way valve 26 and change the direction in which the refrigerant flows through the second four-way valve 26. The valve control unit 96 controls the first flow control valve drive circuit 86, the second flow control valve drive circuit 87, and the ejector solenoid valve drive circuit 89 to change the opening degree of the first flow control valve 31, the second flow control valve 32, and the ejector solenoid valve 78, thereby adjusting the flow rate of the medium. In addition, the valve control unit 96 controls the three-way valve drive circuit 88 to drive the actuator of the three-way valve 33 and change the direction in which the refrigerant flows through the three-way valve 33.

The cooling and heating operations of the air conditioning device 10 of this embodiment configured as described above will be described. Note that the air conditioning device 10 is not limited to cooling and heating operations, and can perform other operations such as dehumidification, defrosting, and sterilization operations. Also, the cooling and heating operations of the air conditioning device 10 are not limited to the examples described below.

First, the cooling operation will be described based on the medium flow pattern shown in FIG. 1. For example, when the air conditioning device 10 is started and the cooling 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 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. 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. The compressor control unit 95 adjusts the frequency of the compressor 23.

When cooling operation is started, the valve control unit 96 controls the first four-way valve drive circuit 84, the second four-way valve drive circuit 85, and the three-way valve drive circuit 88 to change the direction of refrigerant flow in the first four-way valve 25, the second four-way valve 26, and the three-way valve 33 for cooling. The valve control unit 96 also controls the first flow control valve drive circuit 86 and the second flow control valve drive circuit 87 to change the open/close valve state of the first flow control valve 31 and the second flow control valve 32 for cooling.

Specifically, the first four-way valve 25 connects the fourth region 51d and the third region 51c of the first pipe 51, and connects the discharge port 23b of the compressor 23 and the outdoor heat exchanger 21. As a result, the high-pressure, high-temperature gaseous refrigerant discharged from the compressor 23 is supplied to the outdoor heat exchanger 21. The outdoor heat exchanger 21 functions as a condenser and exchanges heat of the refrigerant. In addition, in the case of a general air conditioning device, in order to ensure the refrigerant circulation amount, it is necessary to change the gaseous refrigerant to a liquid refrigerant in the outdoor heat exchanger and supply it to an expansion valve located between the outdoor heat exchanger and the indoor heat exchanger. On the other hand, in the case of the air conditioning device 10 of this embodiment, a gas-liquid separator 61 and an ejector 27 are present between the outdoor heat exchanger 21 and the indoor heat exchanger 41. The ejector 27 is a device that can flow a gas-liquid two-phase refrigerant, so there is no need to completely liquefy the refrigerant in the outdoor unit 11 (outdoor heat exchanger 21).

The gas-liquid two-phase refrigerant supplied from the outdoor heat exchanger 21 to the gas-liquid separator 61 through the second opening 61b is discharged from the third opening 61c, and is supplied as a driving refrigerant to the first inlet 71 of the ejector 27 through the 14th area 55a and the 15th area 55b connected by the flow path switching of the three-way valve 33. The liquid refrigerant separated into gas and liquid in the gas-liquid separator 61 and discharged from the first opening 61a is supplied as a driving refrigerant to the first inlet 71 of the ejector 27 through the 7th area 52c and the 9th area 52e connected by the flow path switching of the second four-way valve 26. Therefore, as mentioned above, in cooling operation, the two-phase gas-liquid refrigerant supplied from the outdoor heat exchanger 21 is once separated into liquid refrigerant and gas refrigerant in the gas-liquid separator 61, but is mixed again and supplied in a two-phase gas-liquid state to the first inlet 71 of the ejector 27 as the driving refrigerant.

In addition, the first area 51a and the second area 51b of the first pipe 51 are connected by the flow path switching by the first four-way valve 25, and the gaseous refrigerant discharged from the indoor heat exchanger 41 can return to the accumulator 24. At this time, the valve control unit 96 controls the first flow control valve drive circuit 86 to open the first flow control valve 31 so that a portion of the gaseous refrigerant discharged from the indoor heat exchanger 41 and returning to the accumulator 24 flows to the second inlet 72 of the ejector 27. Note that, during cooling operation, as shown in FIG. 1, the fourth pipe 54 is not used, so the valve control unit 96 controls the second flow control valve drive circuit 87 to close the second flow control valve 32.

In the ejector 27, as described in FIG. 2, the driving refrigerant flowing in from the first inlet 71 and the suction refrigerant flowing in from the second inlet 72 are mixed and pressurized, and then discharged from the outlet 73. The pressurized gas-liquid two-phase refrigerant is supplied to the indoor heat exchanger 41, which functions as an evaporator, through the sixth region 52b and the fifth region 52a of the second pipe 52 connected by the flow path switching of the second four-way valve 26. As a result of the heat exchange in the indoor heat exchanger 41, cold air can be discharged into the room. As described above, a part of the refrigerant discharged from the indoor heat exchanger 41 is supplied to the second inlet 72 of the ejector 27, so that the indoor heat exchanger 41 changes the refrigerant into a complete gas before discharging it and supplying it to the accumulator 24 and the second inlet 72.

When the above-mentioned circulation of the refrigerant is realized, the control device 14 performs the following control. As described above, in the outdoor unit 11, since the outdoor heat exchanger 21 supplies the gas-liquid two-phase refrigerant to the gas-liquid separator 61, complete liquefaction of the refrigerant is not necessary in the outdoor heat exchanger 21. Therefore, the subcooling SC of the outdoor heat exchanger 21 uses the T4 value detected by the temperature sensor T4 and the T3 value detected by the temperature sensor T3 to control the outdoor fan control unit 93 so that, for example, SC = T4 - T3 ≒ 5°C, and adjusts the speed of the outdoor blower fan 22. In addition, the ejector 27 efficiently exerts a large capacity when the pressure of the refrigerant (pressure conversion) becomes a predetermined pressure (for example, around 0.9 MPa). For example, assuming that a refrigerant pressure of 0.9 MPa is converted to a refrigerant temperature of 3.2°C, the first flow control valve 31 is controlled to adjust the flow rate of the refrigerant so that the detection value (T5 value) of the temperature sensor T5, which is the temperature of the refrigerant flowing through the 10th region 53a, is approximately 3.5°C. In addition, since it is necessary to supply gaseous refrigerant to the second inlet 72 of the ejector 27, for example, the opening degree of the ejector 27 is controlled so that the temperature difference (degree of superheat SH) between the Su value, which is the detection value of the temperature sensor Su, and the T1 value, which is the detection value of the temperature sensor T1, is SH = Su - T1 ≧ 2°C.

In this way, the air conditioning device 10 of this embodiment, which controls the circulation of the refrigerant during cooling operation, uses the ejector 27, so that it is not necessary to completely liquefy the refrigerant by supercooling it in the outdoor heat exchanger 21. In other words, it is possible to reduce the capacity of the outdoor heat exchanger 21. As a result, it is possible to reduce the size of the outdoor heat exchanger 21. In addition, it is possible to sufficiently supply low-temperature, low-pressure, gas-liquid two-phase refrigerant to the indoor heat exchanger 41 via the ejector 27, making it possible to maintain the performance of the indoor heat exchanger 41 during cooling or to reduce the size by improving the cooling performance. In addition, if the outdoor heat exchanger 21 and the indoor heat exchanger 41 are downsized in this way, the total amount of circulating refrigerant can be reduced. In addition, since the pressurized refrigerant can be discharged from the outlet 73 of the ejector 27, the refrigerant can be efficiently flowed to the indoor heat exchanger 41. In other words, it is possible to compensate for part of the pressurization process that was previously performed by the compressor 23 by the function of the ejector 27. In this way, the total amount of circulating refrigerant can be reduced, and the workload of the compressor 23 can be reduced by reducing the pressure increase process, which contributes to energy savings during operation.

Next, the heating operation will be described based on the medium flow pattern shown in FIG. 4. In the case of heating operation, for example, if the air conditioning device 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.

During heating 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. 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. The compressor control unit 95 adjusts the frequency of the compressor 23.

When the heating operation is started, the valve control unit 96 controls the first four-way valve drive circuit 84, the second four-way valve drive circuit 85, and the three-way valve drive circuit 88 to change the direction of refrigerant flow in the first four-way valve 25, the second four-way valve 26, and the three-way valve 33 for heating. The valve control unit 96 also controls the first flow control valve drive circuit 86 and the second flow control valve drive circuit 87 to change the open/close valve state of the first flow control valve 31 and the second flow control valve 32 for heating.

Specifically, the first four-way valve 25 connects the fourth region 51d and the first region 51a of the first pipe 51, and connects the discharge port 23b of the compressor 23 and the indoor heat exchanger 41. As a result, the high-temperature, high-pressure gaseous refrigerant discharged from the compressor 23 is supplied to the indoor heat exchanger 41. The indoor heat exchanger 41 functions as a condenser to exchange heat with the refrigerant and release warm air into the room. In addition, the valve control unit 96 controls the second flow control valve drive circuit 87 to adjust the opening of the second flow control valve 32. As a result, a portion of the high-temperature, high-pressure gaseous refrigerant discharged from the compressor 23 is supplied as a driving refrigerant to the first inlet 71 of the ejector 27 via the fourth pipe 54. In addition, the flow path switching of the first four-way valve 25 connects the third region 51c and the second region 51b of the first pipe 51, and the refrigerant discharged from the outdoor heat exchanger 21 is returned to the accumulator 24. In this case, the first flow control valve 31 is closed, preventing the refrigerant from returning to the accumulator 24 from the second inlet 72 side of the ejector 27.

In addition, the fifth region 52a and the ninth region 52e of the second pipe are connected by the flow path switching of the second four-way valve 26, and the liquid refrigerant discharged from the indoor heat exchanger 41 is supplied to the first inlet 71 of the ejector 27. In addition, the sixth region 52b and the seventh region 52c of the second pipe 52 are connected by the flow path switching of the second four-way valve 26, and the pressurized refrigerant discharged from the outlet 73 of the ejector 27 is supplied to the gas-liquid separator 61 from the first opening 61a. In addition, the fourteenth region 55a and the sixteenth region 55c of the fifth pipe are connected by the flow path switching of the three-way valve 33, and the gaseous refrigerant separated in the gas-liquid separator 61 is supplied to the second inlet 72 of the ejector 27 as suction refrigerant. As mentioned above, the first flow control valve 31 is closed at this time, so the gaseous refrigerant separated by the gas-liquid separator 61 does not return to the accumulator 24.

Here, the first inlet 71 of the ejector 27 is supplied with liquid refrigerant from the indoor heat exchanger 41 and high-temperature, high-pressure gaseous refrigerant from the compressor 23 via the fourth pipe 54. The second inlet 72 of the ejector 27 is supplied with gaseous refrigerant obtained by separating the pressurized gas-liquid two-phase refrigerant discharged from the outlet 73 in the gas-liquid separator 61 as a suction refrigerant. At this time, since the driving refrigerant is a refrigerant in a high-temperature state of the gas-liquid two-phase, the pressurized refrigerant discharged from the outlet 73 is also supplied to the gas-liquid separator 61 while still at a high temperature. As a result, the liquid refrigerant discharged from the second opening 61b of the gas-liquid separator 61 is also supplied to the outdoor heat exchanger 21 while still at a high temperature. The outdoor heat exchanger 21 functions as an evaporator, gasifies the refrigerant, and returns it to the accumulator 24 via the first four-way valve 25.

When the above-mentioned circulation of the refrigerant is realized, the control device 14 performs the following control. In the case of heating operation, as described above, the gaseous refrigerant supplied from the compressor 23 to the indoor heat exchanger 41 is used as the driving refrigerant for the ejector 27. Therefore, for example, the refrigerant can be returned to the outdoor heat exchanger 21 at a subcooled temperature of about 0°C. Also, as described above, the ejector 27 efficiently exerts a large capacity when the refrigerant pressure (pressure conversion) reaches a predetermined pressure (for example, around 0.9 MPa). Therefore, the refrigerant pressure of 0.9 MPa is converted to refrigerant temperature of 3.2°C, and the first flow control valve 31 is controlled to adjust the flow rate of the medium so that the detection value (T5 value) of the temperature sensor T5, which is the temperature of the refrigerant flowing through the 10th region 53a, is around 3.5°C. Also, for example, the opening degree of the ejector 27 is controlled so that the temperature difference (superheat degree SH) between the Su value, which is the detection value of the temperature sensor Su, and the T3 value, which is the detection value of the temperature sensor T3, is SH = Su - T3 ≒ 2°C.

By the way, when performing stable and efficient heating operation in the indoor unit 12, it is desirable that the blowing temperature is as high as possible. In the case of the air conditioning device 10 of this embodiment, supercooling, which reduces the heat exchange rate, is not performed in the indoor heat exchanger 41. Also, as described above, during heating operation of the air conditioning device 10 of this embodiment, high-temperature, high-pressure gaseous refrigerant is supplied from the compressor 23 to the first inlet 71 of the ejector 27, but if too much refrigerant flows to the ejector 27 side, the amount of refrigerant supplied to the indoor heat exchanger 41 side will decrease. For this reason, the valve control unit 96 controls the second flow control valve drive circuit 87, and adjusts the opening degree of the second flow control valve 32 to balance the amount of refrigerant supplied to the indoor heat exchanger 41 and the ejector 27 so that the T1 value, which is the detection value of the temperature sensor T1, can be maintained at the desired temperature. This makes it possible to achieve a high blowing temperature in the indoor unit 12. In this case, for example, the operating frequency of the compressor 23 and the second flow control valve 32 are adjusted so that the difference (subcooling SC) between the refrigerant temperature (T2 value) near the refrigerant outlet (downstream side) of the indoor heat exchanger 41 and the refrigerant temperature (T1 value) inside the indoor heat exchanger 41 is SC = T2 - T1 ≒ 0°C. As a result, the refrigerant is not completely liquefied in the indoor heat exchanger 41 (not subcooled), and the refrigerant is discharged from the indoor heat exchanger 41 in a state that includes a gaseous state, and is supplied to the first inlet 71 of the ejector 27.

In this way, the air conditioning device 10 of this embodiment, which controls the circulation of the refrigerant during heating operation, uses the ejector 27, so that it is not necessary to completely liquefy the refrigerant by supercooling it in the indoor heat exchanger 41. In other words, the capacity of the indoor heat exchanger 41 can be reduced. As a result, the indoor heat exchanger 41 can be made smaller. In addition, since the liquid refrigerant is supplied to the outdoor heat exchanger 21 through the gas-liquid separator 61, the heat exchange efficiency in the outdoor heat exchanger 21 is improved. Therefore, it is possible to make the refrigerant supplied to the outdoor heat exchanger 21 higher than the dew point temperature. As a result, it is possible to make it difficult for frost to form during heat exchange in the outdoor heat exchanger 21. In other words, it is possible to provide an air conditioning device 10 that does not require defrosting processing. In addition, it is possible to make the outdoor heat exchanger 21 smaller while maintaining its performance. In addition, since the indoor heat exchanger 41 does not supercool, it is possible to make the indoor heat exchanger 41 smaller. In addition, if the outdoor heat exchanger 21 and the indoor heat exchanger 41 are made smaller in this way, the total amount of circulating refrigerant can be reduced. In addition, the pressurized refrigerant can be discharged from the outlet 73 of the ejector 27, so the refrigerant can be efficiently circulated to the outdoor heat exchanger 21. In other words, the function of the ejector 27 can compensate for part of the pressurization process that was previously performed by the compressor 23. In this way, the total amount of circulating refrigerant can be reduced, and the workload of the compressor 23 can be reduced by reducing the pressurization process, which contributes to energy savings during operation.

The air conditioning device 10 according to the embodiment described above includes an indoor heat exchanger 41, an outdoor heat exchanger 21, a first pipe 51, a second pipe 52, a compressor 23, a first four-way valve 25, an ejector 27, a second four-way valve 26, a gas-liquid separator 61, a third pipe 53, a fourth pipe 54, and a fifth pipe 55. The indoor heat exchanger 41 is provided in the indoor unit 12. The outdoor heat exchanger 21 is provided in the outdoor unit 11. 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 intake port 23a for sucking in the refrigerant and an exhaust port 23b for discharging the refrigerant. The first four-way valve 25 is provided in the first pipe 51 and can change the direction in which the refrigerant flows. The ejector 27 is provided in the second pipe 52 and has a first inlet 71 through which the refrigerant flows in from the upstream side of the second pipe 52 and a second inlet 72 through which the refrigerant flows in from a pipe different from the second pipe 52, and can mix the refrigerant supplied to the first inlet 71 and the refrigerant supplied to the second inlet 72 and supply the mixed refrigerant from the outlet 73 to the downstream side of the second pipe 52. The second four-way valve 26 is provided in the second pipe 52 and is connected to the first inlet 71 and the outlet 73 of the ejector 27 and can change the direction in which the refrigerant flows out of the outlet 73. The gas-liquid separator 61 is provided in the second pipe 52, and is provided with a first opening 61a connected to the second four-way valve 26, a second opening 61b connected to the outdoor heat exchanger 21, and a third opening 61c through which the gaseous refrigerant passes. The third pipe 53 connects the first pipe 51 connecting the first four-way valve 25 and the suction port 23a of the compressor 23, and the second inlet 72 of the ejector 27. The fourth pipe 54 connects the first pipe 51 connecting the first four-way valve 25 and the indoor heat exchanger 41, and the second pipe 52 connecting the first inlet 71 of the ejector 27 and the second four-way valve 26. The fifth pipe 55 connects the third opening 61c of the gas-liquid separator 61 to the third pipe 53 or the second pipe 52 that connects the first inlet 71 of the ejector 27 to the second four-way valve 26. With this configuration, for example, it is possible to compensate for part of the work of the compressor 23 with the ejector 27, which contributes to energy saving. In addition, it is possible to improve the heat exchange efficiency in the refrigeration cycle, making it possible to reduce the size of the outdoor heat exchanger 21 and the indoor heat exchanger 41, and contributing to a reduction (reduction) of the total amount of circulating refrigerant.

The air conditioning device 10 may also include, for example, a first flow control valve 31 that controls the flow rate of the refrigerant in the third pipe 53. With this configuration, for example, it is possible to easily and accurately control the flow rate of the refrigerant sucked into the ejector 27.

The air conditioning device 10 may also include, for example, a second flow control valve 32 that controls the flow rate of the refrigerant in the fourth pipe 54. With this configuration, for example, it becomes possible to easily balance the amount of refrigerant supplied to the indoor heat exchanger 41 and the amount of refrigerant supplied to the ejector 27 during heating operation, making it easy to perform efficient heating operation.

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 implemented 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, 11...outdoor unit, 12...indoor unit, 13...refrigerant piping, 14...control device, 21...outdoor heat exchanger, 23...compressor, 24...accumulator, 25...first four-way valve, 26...second four-way valve, 27...ejector, 31...first flow control valve, 32...second flow control valve, 33...three-way valve (switching valve), 41...indoor heat exchanger, 51...first pipe, 52...second pipe, 53...third pipe, 54...fourth pipe, 55...fifth pipe, 61...gas-liquid separator, 71...first inlet, 72...second inlet, 73...outlet.

Claims (3)

An indoor heat exchanger provided in the indoor unit;
An outdoor heat exchanger provided in the outdoor unit;
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 a suction port for sucking the refrigerant and a discharge port for discharging the refrigerant;
a first four-way valve provided in the first pipe and capable of changing a flow direction of the refrigerant;
an ejector provided in a second pipe, the ejector having a first inlet through which the refrigerant flows in from an upstream side of the second pipe and a second inlet through which the refrigerant flows in from a pipe different from the second pipe, the ejector being capable of mixing the refrigerant supplied to the first inlet and the refrigerant supplied to the second inlet and supplying the mixed refrigerant from an outlet to a downstream side of the second pipe;
a second four-way valve provided in the second pipe, connected to a first inlet and the outlet of the ejector, and capable of changing a flow direction of the refrigerant flowing out from the outlet;
a gas-liquid separator provided in the second pipe, the gas-liquid separator having a first opening connected to the second four-way valve, a second opening connected to the outdoor heat exchanger, and a third opening through which a gaseous refrigerant passes;
a third pipe connecting the first pipe connecting the first four-way valve and the suction port of the compressor and the second inlet of the ejector; and
a fourth pipe connecting the first pipe connecting the first four-way valve and the indoor heat exchanger and the second pipe connecting the first inlet of the ejector and the second four-way valve;
a fifth pipe connecting the third opening of the gas-liquid separator to the third pipe or the second pipe connecting the first inlet of the ejector to the second four-way valve;
An air conditioning device comprising: The air conditioner according to claim 1, further comprising a first flow control valve in the third pipe for controlling the flow rate of the refrigerant. The air conditioner according to claim 1 or 2, further comprising a second flow control valve in the fourth pipe for controlling the flow rate of the refrigerant.

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