Air conditioner

Abstract

To provide an air conditioner with cold place specifications.SOLUTION: An air conditioner includes an indoor heat exchanger, a first outdoor heat exchanger, a second outdoor heat exchanger, first piping, second piping, a compressor, a four-way valve, a first expansion valve, a receiver tank, third piping, a flow control valve, a first ejector, a second ejector, fourth piping, a first three-way valve, fifth piping, a second expansion valve and a second three-way valve. The first ejector includes: a first inflow port to which a refrigerant can flow in from the third piping; a first inflow / outflow port that is connected to the second outdoor heat exchanger and to / from which the refrigerant can flow in / out; and a second inflow / outflow port that is connected to the four-way valve and to / from which the refrigerant can flow in / out. The second ejector includes: a third inflow / outflow port that is connected to the receiver tank and to / from which the refrigerant can flow in / out; a second inflow port to which the refrigerant can flow in from the first outdoor heat exchanger; and a fourth inflow / outflow port from which the refrigerant can flow out to the second outdoor heat exchanger or to which the refrigerant can flow in from the first outdoor heat exchanger and the second outdoor heat exchanger.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] An embodiment of the present invention relates to an air conditioning apparatus. [Background technology]

[0002] Air conditioners, such as air conditioners, regulate the temperature inside a room 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). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-116124 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, when the above-mentioned air conditioner performs heating operation, the heat from the outside is absorbed and transported to the inside of the room to heat the room, so the heating capacity decreases as the outside temperature drops. This requires the compressor to have a higher rotation speed, which increases power consumption and the compressor load. This tendency is particularly noticeable in cold regions where the outside temperature drops.

[0005] One example of a problem to be solved by the present invention is to provide an air conditioner that is capable of performing good heating operation even in cold regions by suppressing increases in power consumption and operating load of a compressor. [Means for solving the problem]

[0006] An air conditioner according to one embodiment of the present invention includes an indoor heat exchanger, a first outdoor heat exchanger, a second outdoor heat exchanger, a first pipe, a second pipe, a compressor, a four-way valve, a first expansion valve, a receiver tank, a third pipe, a flow control valve, a first ejector, a second ejector, a fourth pipe, a first three-way valve, a fifth pipe, a second expansion valve, and a second three-way valve. The indoor heat exchanger is provided in an indoor unit. The first outdoor heat exchanger is provided in an outdoor unit. The second outdoor heat exchanger is provided in the outdoor unit. The first pipe connects the second outdoor heat exchanger and the indoor heat exchanger, or the first outdoor heat exchanger and the second outdoor heat exchanger and the indoor heat exchanger, and a refrigerant flows through the first pipe. A second pipe connects the indoor heat exchanger and the second outdoor heat exchanger or the indoor heat exchanger and the first outdoor heat exchanger and the second outdoor heat exchanger, and the refrigerant flows through the second pipe. A compressor is provided in the first pipe and has an intake port for sucking the refrigerant and an outlet port for discharging the refrigerant. A four-way valve is provided in the first pipe and is capable of changing the direction in which the refrigerant discharged from the outlet port of the compressor flows. A first expansion valve is provided in the second pipe. A receiver tank is provided between the first expansion valve and the second outdoor heat exchanger and is capable of storing the refrigerant. A third pipe connects the first pipe between the indoor heat exchanger and the four-way valve and the first pipe between the four-way valve and the second outdoor heat exchanger. A flow control valve is provided in the third pipe and controls the flow rate of the refrigerant. The first ejector is provided between the four-way valve and the second outdoor heat exchanger of the first piping, and includes a first inlet through which the refrigerant can flow from the third piping, a first inlet / outlet connected to the second outdoor heat exchanger and through which the refrigerant can flow in and out, and a second inlet / outlet connected to the four-way valve and through which the refrigerant can flow in and out. The second ejector includes a third inlet / outlet connected to the receiver tank and through which the refrigerant can flow in and out, a second inlet / outlet through which the refrigerant can flow in from the first outdoor heat exchanger, and a fourth inlet / outlet through which the refrigerant can flow out to the second outdoor heat exchanger or through which the refrigerant can flow in from the first outdoor heat exchanger and the second outdoor heat exchanger.A fourth pipe connects the first outdoor heat exchanger and the second inlet of the second ejector. A first three-way valve is provided at a connection between the fourth pipe and the first pipe, and switches a flow path between a case where the refrigerant flows from the first outdoor heat exchanger to the fourth pipe and a case where the refrigerant flows from the first pipe to the first outdoor heat exchanger. A fifth pipe connects the receiver tank and the first outdoor heat exchanger. A second expansion valve is provided in the fifth pipe and expands the refrigerant supplied to the first outdoor heat exchanger. A second three-way valve is provided at a connection between the fifth pipe and the second pipe, and switches a flow path between a case where the refrigerant flows from the fifth pipe to the first outdoor heat exchanger and a case where the refrigerant flows from the first outdoor heat exchanger to the second pipe.

[0007] Furthermore, the air conditioner may include, for example, a heat storage material in the first pipe between a connection portion of the third pipe and the four-way valve.

[0008] Furthermore, the second outdoor heat exchanger of an air conditioner may be disposed, for example, upstream of the first outdoor heat exchanger in a flow direction of outdoor air.

[0009] Furthermore, the first outdoor heat exchanger of the air conditioner may have a greater heat exchange capacity than the second outdoor heat exchanger, for example.

[0010] According to the above air conditioner, for example, it is possible to provide an air conditioner that can suppress increases in power consumption and operating load of the compressor and can perform good heating operation even in cold regions. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a refrigerant system diagram of an air conditioner according to an embodiment, and is also an illustrative and schematic diagram showing the flow of refrigerant during heating operation. [Diagram 2] FIG. 2 is an illustrative and schematic cross-sectional view illustrating the configuration of a first ejector mounted in the outdoor unit of the air conditioner according to the embodiment. [Diagram 3] FIG. 3 is an exemplary schematic block diagram showing a control device for an air conditioner according to an embodiment and a configuration controlled by the control device. [Figure 4] FIG. 4 is an illustrative schematic front view showing the appearance of the outdoor unit of the air conditioner according to the embodiment. [Diagram 5] FIG. 5 is an exemplary schematic cross-sectional view showing a cross section taken along line AA of FIG. [Figure 6] FIG. 6 is a refrigerant system diagram of an air conditioner according to an embodiment, and is also an illustrative and schematic diagram showing the flow of refrigerant during cooling operation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Several embodiments will be described below with reference to Figs. 1 to 6. In this specification, components according to the embodiments and their descriptions may be described in a number 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.

[0013] FIG. 1 is an exemplary schematic diagram showing a refrigerant system diagram of an air conditioner 10 according to an embodiment. The air conditioner 10 is, for example, a home air conditioner designed for cold climates. Note that the air conditioner 10 is not limited to this example, and may be another air conditioner such as a commercial air conditioner. Note that the air conditioner 10 can, of course, be used not only in cold climates, but also in normal climates.

[0014] 1, an 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 disposed, for example, outdoors. The indoor unit 12 is disposed, for example, indoors.

[0015] The air conditioner 10 includes a refrigeration cycle in which an outdoor unit 11 and an indoor unit 12 are connected by refrigerant piping 13. A 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.

[0016] The outdoor unit 11 includes an outdoor heat exchanger 21, an outdoor blower fan 22, a compressor 23, an accumulator 24, a four-way valve 25, a flow control valve 26, a first expansion valve 27, a second expansion valve 28, a first three-way valve 29 (switching valve), a second three-way valve 30 (switching valve), a first ejector 31, a second ejector 32, a receiver tank 33, a heat storage material 34, and flow dividing sections 35a to 35c, 36a to 36c. The indoor unit 12 includes an indoor heat exchanger 41 and an indoor blower fan 42. The heat storage material 34 may be omitted. The outdoor heat exchanger 21 includes a first outdoor heat exchanger 21A and a second outdoor heat exchanger 21B.

[0017] The refrigerant pipes 13 are pipes made of a metal such as copper or aluminum through which a refrigerant flows. The refrigerant pipes 13 include a first pipe 51, a second pipe 52, a third pipe 53, a fourth pipe 54, a fifth pipe 55, and the like.

[0018] The first piping 51 connects the second outdoor heat exchanger 21B and the indoor heat exchanger 41, or connects the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B and the indoor heat exchanger 41. The compressor 23, the accumulator 24, the four-way valve 25, the first three-way valve 29, the first ejector 31, and the flow dividing sections 35a to 35c are provided in the first piping 51. The first piping 51 has a first region 51a, a second region 51b, a third region 51c, a fourth region 51d, a fifth region 51e, a sixth region 51f, a seventh region 51g, an eighth region 51h, and a ninth region.

[0019] The first ejector 31 is provided between the four-way valve 25 of the first pipe 51 and the second outdoor heat exchanger 21B. The first ejector 31 includes a first inlet 31a through which the refrigerant can flow from the third pipe 53, a first inlet / outlet 31b connected to the second outdoor heat exchanger 21B through which the refrigerant can flow in and out, and a second inlet / outlet 31c connected to the four-way valve 25 through which the refrigerant can flow in and out.

[0020] The first area 51a is a piping area that connects the heat storage material 34 and the indoor heat exchanger 41. The second area 51b is a piping area that connects the four-way valve 25 and the heat storage material 34. When the heat storage material 34 is omitted, the first area 51a and the second area 51b are connected. The third area 51c is a piping area that connects the four-way valve 25 and the discharge port 23b of the compressor 23. The fourth area 51d is a piping area that connects the four-way valve 25 and the accumulator 24. The fifth area 51e is a piping area that connects the four-way valve 25 and the second inlet / outlet 31c of the first ejector 31. The sixth area 51f is a piping area that connects the first inlet / outlet 31b of the first ejector 31 and the flow dividing section 35a. The seventh region 51g is a piping region that connects the diverter 35a and the first three-way valve 29. The eighth region 51h is a piping region that connects the first three-way valve 29 and the diverter 35b of the first outdoor heat exchanger 21A. The ninth region 51i is a piping region that connects the diverter 35a and the diverter 35c of the second outdoor heat exchanger 21B. During heating operation, the high-pressure, high-temperature refrigerant discharged from the compressor 23 is supplied to the indoor heat exchanger 41 side. On the other hand, during cooling operation, the high-pressure, high-temperature refrigerant discharged from the compressor 23 is supplied to the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B side.

[0021] The second piping 52 connects the indoor heat exchanger 41 and the second outdoor heat exchanger 21B or connects the indoor heat exchanger 41 and the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B. The first expansion valve 27, the receiver tank 33, the second ejector 32, the second three-way valve 30, and the flow dividing sections 36a to 36c are provided in the second piping 52.

[0022] The second ejector 32 is equipped with a third inlet / outlet 32a through which the refrigerant can flow in and out from the receiver tank 33, a second inlet 32b through which the refrigerant can flow in from the first outdoor heat exchanger 21A, and a fourth inlet / outlet 32c through which the refrigerant can flow out to the second outdoor heat exchanger 21B or through which the refrigerant can flow in from the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B.

[0023] The second piping 52 has a tenth region 52a, an eleventh region 52b, a twelfth region 52c, a thirteenth region 52d, a fourteenth region 52e, a fifteenth region 52f, and a sixteenth region 52g. The tenth region 52a is a piping region that connects the first expansion valve 27 and the indoor heat exchanger 41. The eleventh region 52b is a piping region that connects the first expansion valve 27 and the first opening 33a of the receiver tank 33. The receiver tank 33 is a tank that temporarily stores the refrigerant circulating through the refrigerant piping 13, and includes a first opening 33a, a second opening 33b, and a third opening 33c through which the refrigerant can flow in and out. The twelfth region 52c is a piping region that connects the second opening 33b of the receiver tank 33 and the third inlet / outlet 32a of the second ejector 32. The thirteenth region 52d is a piping region that connects the fourth inlet / outlet 32c of the second ejector 32 and the diverter 36a. The fourteenth region 52e is a piping region that connects the diverter 36a and the second three-way valve 30. The fifteenth region 52f is a piping region that connects the second three-way valve 30 and the diverter 36b of the first outdoor heat exchanger 21A. The sixteenth region 52g is a piping region that connects the diverter 36a and the diverter 36c of the second outdoor heat exchanger 21B. During heating operation, the refrigerant that has undergone heat exchange and flows out of the indoor heat exchanger 41 is supplied to the second outdoor heat exchanger 21B side.

[0024] The third piping 53 connects the first piping 51 (first region 51a) between the indoor heat exchanger 41 and the four-way valve 25 (thermal storage material 34) and the first piping 51 (first inlet 31a of the first ejector 31) between the four-way valve 25 and the second outdoor heat exchanger 21B. The flow control valve 26 is provided in the third piping 53. The third piping 53 has a 17th region 53a and an 18th region 53b. The 17th region 53a is a piping region that connects the first region 51a and the flow control valve 26. The 18th region 53b is a piping region that connects the flow control valve 26 and the first inlet 31a of the first ejector 31. During heating operation, a part of the high-pressure, high-temperature refrigerant discharged from the compressor 23 is supplied to the first inlet 31a of the first ejector 31 through the third pipe 53. On the other hand, during cooling operation, the flow control valve 26 is closed, and the refrigerant does not flow through the third pipe 53.

[0025] The fourth pipe 54 connects the first outdoor heat exchanger 21A (first three-way valve 29) and the second inlet 32b of the second ejector. During heating operation, the refrigerant is supplied from the first outdoor heat exchanger 21A to the second inlet 32b of the second ejector 32. On the other hand, during cooling operation, the flow path of the first three-way valve 29 is switched so that the refrigerant does not flow through the fourth pipe 54.

[0026] The fifth pipe 55 connects the third opening 33c of the receiver tank 33 and the first outdoor heat exchanger 21A. The second expansion valve 28 is provided in the fifth pipe 55. The fifth pipe 55 has a 19th region 55a and a 20th region 55b. The 19th region 55a is a piping region that connects the third opening 33c of the receiver tank 33 and the second expansion valve 28. The 20th region 55b is a piping region that connects the second expansion valve 28 and the second three-way valve 30. During heating operation, the refrigerant is supplied from the third opening 33c of the receiver tank 33 to the first outdoor heat exchanger 21A via the second expansion valve 28. During cooling operation, the refrigerant does not flow through the fifth pipe 55 due to the flow path switching of the second three-way valve 30.

[0027] As described above, the outdoor heat exchanger 21 of the outdoor unit 11 is composed of the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B. The outdoor heat exchanger 21 absorbs heat from the refrigerant as an evaporator or releases heat from the refrigerant as a condenser depending on the direction of the refrigerant flow. The outdoor blower fan 22 blows air to the outdoor heat exchanger 21 and promotes heat exchange between the refrigerant and the 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. As shown in FIG. 1, the flow dividing sections 35b, 36b, 35c, and 36c are arranged before and after the inlet and outlet of the refrigerant of the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B, and are configured to divide the inside of the outdoor heat exchanger 21 into a plurality of paths so that the refrigerant can pass through efficiently. The number of paths can be set appropriately depending on the heat exchange capacity of the outdoor heat exchanger 21. In FIG. 1, the paths constituting the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B are depicted as vertically long rectangles with hatching. In order to show that there is a difference in heat exchange capacity between the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B, an example in which the first outdoor heat exchanger 21A is configured with, for example, four paths is shown, and an example in which the second outdoor heat exchanger 21B is configured with, for example, two paths is shown. These numbers of paths are schematic and can be set appropriately depending on the heat exchange capacity required by the outdoor heat exchanger 21. The same applies to FIG. 6 described later.

[0028] The compressor 23 has a suction port 23a and a discharge port 23b. The compressor 23 draws in a refrigerant from the suction port 23a and discharges the compressed refrigerant from the discharge port 23b. In this way, the compressor 23 compresses the refrigerant in a refrigeration cycle and causes the refrigerant to circulate.

[0029] 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.

[0030] The four-way valve 25 is connected to the indoor heat exchanger 41 and the flow control valve 26 via the outdoor heat exchanger 21, the accumulator 24, the compressor 23, and the heat storage material 34. The four-way valve 25 switches the flow paths connected to the outdoor heat exchanger 21, the accumulator 24, the compressor 23, and the indoor heat exchanger 41, respectively, during heating operation and cooling operation, to change the direction in which the refrigerant flows.

[0031] During heating operation, as shown in FIG. 1, the four-way valve 25 connects the discharge port 23b of the compressor 23 to the indoor heat exchanger 41 (heat storage material 34) and supplies a high-temperature, high-pressure gaseous refrigerant to the indoor heat exchanger 41. The indoor heat exchanger 41 functions as a condenser and releases warm air into the room as a result of heat exchange. The refrigerant that has passed through the indoor heat exchanger 41 is supplied as a driving flow to the second ejector 32 via the receiver tank 33. The refrigerant supplied to the receiver tank 33 is expanded and cooled when passing through the second expansion valve 28, and is supplied to the first outdoor heat exchanger 21A that functions as an evaporator. The refrigerant gasified in the first outdoor heat exchanger 21A is supplied to the second ejector 32 as a suction flow. The refrigerant that has passed through the second ejector 32 is supplied to the second outdoor heat exchanger 21B that functions as an evaporator and gasified. The gas refrigerant that has passed through the second outdoor heat exchanger 21B is supplied as a suction flow to the first ejector 31, mixed with a driving flow supplied to the first ejector 31 via the third piping 53, discharged from the first ejector 31, and returned to the compressor 23 via the accumulator 24. This achieves a heating operation cycle. Details of the outdoor heat exchanger 21 (the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B), the first ejector 31, and the second ejector 32 will be described later.

[0032] During cooling operation, the four-way valve 25 connects the discharge port 23b of the compressor 23 to the first ejector 31. The refrigerant that has passed through the first ejector 31 passes through the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B that function as condensers, is supplied to the receiver tank 33, and flows out from the first opening 33a. The refrigerant that has flowed out from the first opening 33a of the receiver tank 33 is expanded and cooled by the first expansion valve 27, and is supplied to the indoor heat exchanger 41. The indoor heat exchanger 41 functions as an evaporator and releases cold air into the room as a result of heat exchange. The refrigerant discharged from the indoor heat exchanger 41 is returned to the accumulator 24 (compressor 23). This achieves a cooling operation cycle.

[0033] The flow control valve 26 is basically controlled to be fully open during heating operation. The flow control valve 26 determines the distribution amount of high-temperature, high-pressure gas refrigerant to be flowed from the compressor 23 to the indoor heat exchanger 41 side and the first ejector 31 side during heating operation. On the other hand, the flow control valve 26 is closed during cooling operation to block the flow of refrigerant. Note that the flow control valve 26 may be another type of solenoid valve or the like as long as it can adjust the flow rate.

[0034] The first expansion valve 27 and the second expansion valve 28 are, for example, electromagnetic expansion valves. The first expansion valve 27 and the second expansion valve 28 may be other expansion valves. The first expansion valve 27 and the second expansion valve 28 adjust the amount of refrigerant passing through them by controlling the opening degree, thereby determining the expansion amount of the refrigerant and adjusting the refrigerant temperature. The first expansion valve 27 is fully opened during heating operation, and the refrigerant passes through without expanding. On the other hand, during cooling operation, the first expansion valve 27 adjusts the opening of the valve, expands the refrigerant, and supplies the low-temperature refrigerant to the indoor heat exchanger 41. The second expansion valve 28 adjusts the opening of the valve during heating operation, and adjusts the amount of refrigerant passing through them to determine the expansion amount of the refrigerant and adjusts the refrigerant temperature (low temperature). The second expansion valve 28 is closed during cooling operation, and blocks the flow of refrigerant through the fifth pipe 55.

[0035] The first three-way valve 29 and the second three-way valve 30 may be other types of solenoid valves etc. as long as they can switch the flow path. The first three-way valve 29 connects the first outdoor heat exchanger 21A (flow dividing section 35b) to the second inlet 32b of the second ejector 32 during heating operation, and connects the flow dividing section 35a (the first inlet / outlet 31b of the first ejector 31) to the first outdoor heat exchanger 21A (flow dividing section 35b) during cooling operation. That is, the first three-way valve 29 is provided at the connection section between the fourth pipe 54 and the first pipe 51, and switches the flow path between the case where the refrigerant flows from the first outdoor heat exchanger 21A to the fourth pipe 54 and the case where the refrigerant flows from the first pipe 51 to the first outdoor heat exchanger 21A. Moreover, the second three-way valve 30 connects the second expansion valve 28 and the first outdoor heat exchanger 21A (the branching section 36b) during heating operation, and connects the branching section 36b (the first outdoor heat exchanger 21A) and the branching section 36a (the fourth inlet / outlet 32c of the second ejector 32) during cooling operation. That is, the second three-way valve 30 is provided at the connection section between the fifth pipe 55 and the second pipe 52, and switches the flow path between the case where the refrigerant flows from the fifth pipe 55 to the first outdoor heat exchanger 21A and the case where the refrigerant flows from the first outdoor heat exchanger 21A to the second pipe 52.

[0036] The first ejector 31 is provided in the first pipe 51. The first ejector 31 includes a first inlet 31a, a first inlet / outlet 31b, and a second inlet / outlet 31c. The first inlet 31a receives a high-temperature, high-pressure gas refrigerant supplied from the compressor 23 through the third pipe 53 as a driving flow during heating operation. During cooling operation, the first inlet 31a is fully closed by a first ejector solenoid valve 61 described later to stop the ejector function. Specifically, the first inlet 31a is used to allow the refrigerant that has flowed in from the second inlet / outlet 31c to flow out from the first inlet / outlet 31b. The first inlet / outlet 31b receives the gas refrigerant discharged from the second outdoor heat exchanger 21B as a suction flow during heating operation. During cooling operation, the first inlet / outlet 31b allows the refrigerant that has flowed in from the second inlet / outlet 31c to flow out as it is. During heating operation, the second inlet / outlet 31c mixes the refrigerant supplied to the first inlet 31a and the refrigerant supplied to the first inlet / outlet 31b and discharges (supplies) the pressurized refrigerant to the compressor 23. During cooling operation, the second inlet / outlet 31c receives the high-temperature, high-pressure refrigerant discharged from the compressor 23 and causes it to flow out from the first inlet / outlet 31b.

[0037] The second ejector 32 is provided on the second pipe 52. The second ejector 32 includes a third inlet / outlet 32a, a second inlet 32b, and a fourth inlet / outlet 32c. The third inlet / outlet 32a receives liquid refrigerant from the second opening 33b of the receiver tank 33 as a driving flow during heating operation. During cooling operation, the third inlet / outlet 32a is fully opened by a second ejector solenoid valve 62 described later to stop the ejector function. Specifically, the refrigerant flowing in from the fourth inlet / outlet 32c is used to flow out from the third inlet / outlet 32a. The second inlet / outlet 32b receives gas refrigerant discharged from the first outdoor heat exchanger 21A as a suction flow during heating operation. During cooling operation, the flow of refrigerant is stopped in the fourth pipe 54 connected to the second inlet 32b by the flow path switching of the first three-way valve 29. During heating operation, the fourth inlet / outlet 32c mixes the refrigerant supplied to the third inlet / outlet 32a and the refrigerant supplied to the second inlet / outlet 32b and discharges (supplies) the refrigerant in a pressurized state to the second outdoor heat exchanger 21B. During cooling operation, the fourth inlet / outlet 32c receives the refrigerant that has been heat exchanged in the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B. The refrigerant that flows in from the fourth inlet / outlet 32c flows out directly from the third inlet / outlet 32a toward the receiver tank 33.

[0038] The first ejector 31 and the second ejector 32 have the same structure. Therefore, the structure of the first ejector 31 will be mainly described in FIG.

[0039] 2 is an exemplary and schematic cross-sectional view showing the structure of the first ejector 31 of this embodiment. As shown in FIG. 2, the first ejector 31 has a simple structure, and therefore is easy to maintain and to install in the air conditioning device 10. The structure of the first ejector 31 is not limited to the example shown in FIG. 2. As described above, the first ejector 31 is provided with the first inlet 31a, the first inlet outlet 31b, the second inlet outlet 31c, the nozzle portion 31d, the suction portion 31e, the mixer portion 31f, and the diffuser portion 31g.

[0040] 1 and 2, the first inlet 31a is connected to the flow control valve 26 via the first ejector solenoid valve 61 and the 18th region 53b of the third pipe 53. For example, during heating operation, the first ejector solenoid valve 61 is controlled to open so that the high-temperature, high-pressure gas refrigerant discharged from the compressor 23 is regulated and supplied to the first inlet 31a as a driving flow. During cooling operation, the ejector function is disabled by closing the first ejector solenoid valve 61 provided at the first inlet 31a.

[0041] The first inlet / outlet 31b is connected to the sixth region 51f of the first pipe 51. For example, during heating operation, the gaseous refrigerant discharged from the second outdoor heat exchanger 21B flows into the first inlet / outlet 31b as a suction flow. During cooling operation, the high-temperature, high-pressure gaseous refrigerant that flows in from the second inlet / outlet 31c flows out from the first inlet / outlet 31b.

[0042] The second inlet / outlet 31c is connected to the fifth region 51e of the first pipe 51. During heating operation, the second inlet / outlet 31c discharges the gas refrigerant pressurized by the first ejector 31. During cooling operation, the second inlet / outlet 31c is supplied with high-temperature, high-pressure gas refrigerant discharged from the compressor 23.

[0043] As described above, during heating operation, the first ejector 31 can mix the refrigerant (driving flow) supplied to the first inlet 31a with the refrigerant (suction flow) supplied to the first inlet 31b, increase the pressure of the refrigerant, and release it from the second inlet 31c. Therefore, the first ejector 31 can return the refrigerant that has been increased in pressure and temperature by mixing with the refrigerant to the compressor 23 side.

[0044] As shown in FIG. 2, the nozzle portion 31d is provided between the first inlet 31a and the mixing portion 31f. The nozzle portion 31d is a flow path having a portion tapering toward the mixing portion 31f and a portion gradually expanding toward the mixing portion 31f. The shape of the nozzle portion 31d 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 31d decompresses and expands the refrigerant that has flowed into the first inlet 31a, and sprays it into the mixing portion 31f. Since the pressure near the outlet of the nozzle portion 31d is low, the first inlet 31a connected to the nozzle portion 31d can suck in the refrigerant.

[0045] The suction section 31e is provided between the first inlet / outlet 31b and the mixing section 31f. The suction section 31e is provided around the nozzle section 31d and is a substantially cylindrical flow path having a portion tapered toward the mixing section 31f. The suction section 31e reduces the pressure of the refrigerant that has flowed into the first inlet / outlet 31b and expands it to eject it into the mixing section 31f. Since the pressure near the outlet of the suction section 31e is low, the first inlet / outlet 31b connected to the suction section 31e can suck in the refrigerant.

[0046] The mixing section 31f is provided between the nozzle section 31d and the suction section 31e and the diffuser section 31g. In the first ejector 31, the mixing section 31f mixes the refrigerant ejected from the suction section 31e with the refrigerant ejected from the nozzle section 31d.

[0047] The diffuser section 31g is provided between the mixing section 31f and the second inlet / outlet 31c. The diffuser section 31g is a flow path having a portion expanding toward the second inlet / outlet 31c. The refrigerant mixed in the mixing section 31f is decelerated and pressurized in the diffuser section 31g, and is discharged from the second inlet / outlet 31c.

[0048] The first ejector 31 has a first ejector solenoid valve 61. The first ejector solenoid valve 61 can adjust the ejector effect (refrigerant pressure, refrigerant temperature, etc.) by opening and closing the first inlet 31a. In FIG. 2, the first ejector solenoid valve 61 is shown to be located outside the nozzle portion 31d, but the first ejector solenoid valve 61 may be provided inside the nozzle portion 31d or in another portion. For example, the first ejector solenoid valve 61 may be a needle-shaped valve that is inserted into the nozzle portion 31d to adjust the opening degree. The first ejector solenoid valve 61 adjusts the amount of refrigerant supplied to the first inlet 31a by controlling the opening degree. The first ejector solenoid valve 61 may be omitted, and the flow rate of the first ejector 31 may be controlled by the flow control valve 26. In addition, in the first ejector 31, the amount of refrigerant supplied to the first inlet / outlet 31b can be adjusted by the amount of refrigerant discharged from the second outdoor heat exchanger 21B, but an ejector solenoid valve may be provided at or inside the first inlet / outlet 31b, similar to the first inlet 31a.

[0049] The second ejector 32 and the first ejector 31 have the same basic operation except for the piping to which they are connected, and therefore a detailed description of the second ejector 32 will be omitted here.

[0050] Returning to FIG. 1, the receiver tank 33 is an example of a gas-liquid separator having a simple structure, which is composed of a storage tank having a first opening 33a, a second opening 33b, and a third opening 33c, and can temporarily store a refrigerant. In heating operation, the refrigerant flows in from the first opening 33a, and flows out from the second opening 33b and the third opening 33c. In cooling operation, the refrigerant flows in from the second opening 33b, and flows out from the first opening 33a. When the refrigerant is in a gas-liquid two-phase state, the gas part of the refrigerant put into the storage tank moves to the top of the storage tank, and the liquid part moves to the bottom of the storage tank. As a result, the separated liquid refrigerant can be obtained by taking out the refrigerant from the bottom surface of the storage tank. In addition, the separated gaseous refrigerant can be obtained by taking out the refrigerant from an upper part such as the top surface of the storage tank.

[0051] The heat storage material 34 has, 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 34 may have other latent heat storage materials. The heat storage material 34 in this embodiment is, for example, a heat storage material that can be used in a temperature range of about 10°C to about 100°C. In the air conditioner 10 of this embodiment, the high-temperature and high-pressure gas refrigerant discharged from the compressor 23 during heating operation is distributed to the indoor heat exchanger 41 side and the third pipe 53 as a driving flow for the first ejector 31. Therefore, the amount of heat on the indoor heat exchanger 41 side may be insufficient. Therefore, for example, when the air conditioner 10 is stopped or there is no person in the room, heat is stored in the heat storage material 34, and the heat is used to compensate for the temperature of the refrigerant, contributing to improving the capacity during heating operation. Note that when the heating operation capacity can be sufficiently secured (when the blowing temperature of the indoor unit 12 can be set to, for example, 55°C), the heat storage material 34 may be omitted.

[0052] The flow dividing sections 35a and 36a are sections that divide the refrigerant between the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B, or combine the refrigerant that has flowed through the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B. The flow dividing sections 35b and 36b are sections that distribute the refrigerant to multiple paths formed inside the first outdoor heat exchanger 21A, or combine the refrigerant that has passed through multiple paths. The flow dividing sections 35c and 36c are sections that distribute the refrigerant to multiple paths formed inside the second outdoor heat exchanger 21B, or combine the refrigerant that has passed through multiple paths.

[0053] The control device 14 controls the outdoor blower fan 22, the indoor blower fan 42, the compressor 23, each valve, and the like 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, an indoor control device 14b provided in the indoor unit 12, and the like. The outdoor control device 14a and the indoor control device 14b are electrically connected to each other to transmit and receive control signals to each other, and cooperate 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, for example, 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 formed into 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.

[0054] 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.

[0055] Fig. 3 is an exemplary schematic block diagram showing the control device 14 of the air conditioner 10 of this embodiment and a configuration controlled by the control device 14. As shown in Fig. 3, the air conditioner 10 of this embodiment has an outdoor fan drive circuit 81, an indoor fan drive circuit 82, an inverter circuit 83, a four-way valve drive circuit 84, a flow control valve drive circuit 85, a first expansion valve drive circuit 86, a second expansion valve drive circuit 87, a first three-way valve drive circuit 88, a second three-way valve drive circuit 89, a first ejector solenoid valve drive circuit 90a, a second ejector solenoid valve drive circuit 90b, and the like.

[0056] 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 to change 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.

[0057] The four-way valve drive circuit 84 is a drive circuit for the four-way valve 25. The flow control valve drive circuit 85 is a drive circuit for the flow control valve 26. The first expansion valve drive circuit 86 is a drive circuit for the first expansion valve 27. The second expansion valve drive circuit 87 is a drive circuit for the second expansion valve 28. The first three-way valve drive circuit 88 is a drive circuit for the first three-way valve 29. The second three-way valve drive circuit 89 is a drive circuit for the second three-way valve 30. The first ejector solenoid valve drive circuit 90a is a drive circuit for the first ejector solenoid valve 61 of the first ejector 31. The second ejector solenoid valve drive circuit 90b is a drive circuit for the second ejector solenoid valve 62 of the second ejector 32.

[0058] The control device 14 is connected to a temperature sensor T (for example, a temperature sensor T1 for measuring the internal temperature of the heat storage material 34) provided in the refrigerant pipe 13, the indoor heat exchanger 41, the outdoor heat exchanger 21, the heat storage material 34, etc., an outdoor fan drive circuit 81, an indoor fan drive circuit 82, an inverter circuit 83, a four-way valve drive circuit 84, a flow control valve drive circuit 85, a first expansion valve drive circuit 86, a second expansion valve drive circuit 87, a first three-way valve drive circuit 88, a second three-way valve drive circuit 89, a first ejector solenoid valve drive circuit 90a, and a second ejector solenoid valve drive circuit 90b. 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.

[0059] The temperature acquisition unit 91 uses each temperature sensor T to measure the temperature of each part in the refrigeration cycle, and reflects the measured temperature in the control of each drive circuit.

[0060] The operation switching unit 92 switches the air conditioner 10 between cooling operation, heating operation, dehumidification operation, defrosting operation, and other operations.

[0061] The outdoor fan control section 93 controls the outdoor blower fan 22. For example, the outdoor fan control section 93 controls the outdoor fan drive circuit 81 to control the rotation speed of the motor of the outdoor blower fan 22.

[0062] The indoor fan control unit 94 controls the indoor blower fan 42. For example, the indoor fan control unit 94 controls the indoor fan drive circuit 82 to control the rotation speed of the motor of the indoor blower fan 42.

[0063] The compressor control unit 95 controls the compressor 23. For example, the compressor control unit 95 controls the inverter circuit 83 to control the frequency (operating frequency) of the compressor 23 by inverter control.

[0064] The valve control unit 96 controls the four-way valve 25, the flow control valve 26, the first expansion valve 27, the second expansion valve 28, the first three-way valve 29, the second three-way valve 30, the first ejector solenoid valve 61, and the second ejector solenoid valve 62. The valve control unit 96 controls the four-way valve drive circuit 84 to drive the actuator of the four-way valve 25 and change the direction in which the refrigerant flows through the four-way valve 25. The valve control unit 96 controls the flow control valve drive circuit 85 to drive the actuator of the flow control valve 26 and adjust the amount of refrigerant flowing through the flow control valve 26. The valve control unit 96 controls the first expansion valve drive circuit 86 and the second expansion valve drive circuit 87 to change the opening degrees of the first expansion valve 27 and the second expansion valve 28, and adjust the expansion amount of the refrigerant (refrigerant temperature, etc.). The valve control unit 96 controls the first three-way valve drive circuit 88 and the second three-way valve drive circuit 89 to drive the actuators of the first three-way valve 29 and the second three-way valve 30 and change the direction in which the refrigerant flows. The valve control unit 96 controls the first ejector solenoid valve drive circuit 90a and the second ejector solenoid valve drive circuit 90b to change the openings of the first ejector solenoid valve 61 and the second ejector solenoid valve 62, thereby adjusting the flow rates of the medium in the first ejector 31 and the second ejector 32 and adjusting the ejector effect amount.

[0065] Fig. 4 is an exemplary schematic front view showing the appearance of the outdoor unit 11 of the air conditioner 10. Fig. 5 is an exemplary schematic cross-sectional view showing the AA cross section of Fig. 4.

[0066] 1 inside a box-shaped housing 11A, and is installed outdoors (on a balcony, an exterior wall, a rooftop, etc.) to exchange heat with outdoor air. Note that in Figures 4 and 5, components other than the first outdoor heat exchanger 21A, the second outdoor heat exchanger 21B, and the outdoor blower fan 22 are not shown.

[0067] 5, the second outdoor heat exchanger 21B is disposed upstream of the first outdoor heat exchanger 21A with respect to the flow direction W of the outdoor air generated by the outdoor blower fan 22. In other words, the outdoor blower fan 22 is disposed on the rear face B side of the outdoor unit 11, and the outdoor air drawn into the housing 11A from the front face F side is first directed against the second outdoor heat exchanger 21B for heat exchange, and then directed against the first outdoor heat exchanger 21A disposed on the rear side thereof for heat exchange.

[0068] As described above, in the case of heating operation, the refrigerant flows from the second opening 33b of the receiver tank 33 to the third inlet / outlet 32a of the second ejector 32, and the refrigerant temperature is changed to, for example, -16°C by adjusting the flow rate of the second ejector 32, and is supplied to the second outdoor heat exchanger 21B. At this time, the refrigerant is supplied to the second expansion valve 28 from the third opening 33c of the receiver tank 33, and as a result of the expansion action, the refrigerant temperature is changed to, for example, -21°C, and is supplied to the first outdoor heat exchanger 21A. Then, it is assumed that the extremely low temperature condition of the outside air in a cold winter region is -15°C. At this time, as described above, for example, a refrigerant at -16°C flows through the second outdoor heat exchanger 21B. Since the dew point temperature at -15°C (humidity 90%) is -16.3°C, a refrigerant at a temperature higher than the dew point temperature flows through the second outdoor heat exchanger 21B. As a result, heat exchange is possible without condensation or frost on the second outdoor heat exchanger 21B, and the refrigerant can be gasified. As described above, for example, a refrigerant at -21°C flows through the first outdoor heat exchanger 21A. In a normal refrigerant circuit, the refrigerant will condense and freeze because it is below the dew point, making a defrosting operation necessary. However, air at, for example, -15.5°C that has passed through the second outdoor heat exchanger 21B flows through the first outdoor heat exchanger 21A of this embodiment. As a result, no condensation occurs in the first outdoor heat exchanger 21A, and no frost forms. In other words, basically, in the case of the air conditioning device 10 of this embodiment, a configuration can be configured in which a defrosting operation is not required even when a heating operation is performed under extremely low temperature conditions, that is, a heating operation is performed nonstop.

[0069] The first outdoor heat exchanger 21A is set to have a larger heat exchange capacity than the second outdoor heat exchanger 21B. For example, the area of ​​the fins for heat exchange formed on the surface of the heat exchanger is set to be larger in the first outdoor heat exchanger 21A than in the second outdoor heat exchanger 21B. In this case, heat exchange during heating operation is mainly performed in the first outdoor heat exchanger 21A, and the second outdoor heat exchanger 21B is configured to perform heat exchange for gasifying the refrigerant supplied to the first inlet / outlet 31b of the first ejector 31.

[0070] The heating operation of the air conditioner 10 of this embodiment configured as described above will be described based on the medium flow pattern shown in FIG.

[0071] In the case of heating operation, if the air conditioning apparatus 10 starts up 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 at the start of the heating operation.

[0072] 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.

[0073] When the heating operation is started, the valve control unit 96 controls the four-way valve drive circuit 84, the first three-way valve drive circuit 88, and the second three-way valve drive circuit 89 to change the direction of refrigerant flow in the four-way valve 25, the first three-way valve 29, and the second three-way valve 30 for heating. In addition, the valve control unit 96 controls the flow control valve drive circuit 85, the first expansion valve drive circuit 86, the second expansion valve drive circuit 87, the first ejector solenoid valve drive circuit 90a, and the second ejector solenoid valve drive circuit 90b to change the open / close valve states of the flow control valve 26, the first expansion valve 27, the second expansion valve 28, the first ejector solenoid valve 61, and the second ejector solenoid valve 62 for heating.

[0074] Specifically, the four-way valve 25 connects the third region 51c and the second region 51b of the first pipe 51, and connects the discharge port 23b of the compressor 23 and the indoor heat exchanger 41 via the heat storage material 34 and the first region 51a. 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, exchanges heat of the refrigerant, and releases hot air into the room. In addition, the valve control unit 96 controls the flow control valve drive circuit 85 to adjust the opening of the flow control valve 26 (basically adjusts it to full opening). As a result, a part of the high-temperature, high-pressure gaseous refrigerant (for example, gas refrigerant at 90°C) discharged from the compressor 23 is supplied as a driving flow to the first inlet 31a of the first ejector 31 via the third pipe 53. The refrigerant that has passed through the indoor heat exchanger 41 is supplied to the receiver tank 33 from the first opening 33a, and is supplied as a driving flow to the third inlet / outlet 32a of the second ejector 32 from the second opening 33b. The refrigerant supplied to the receiver tank 33 is supplied to the second expansion valve 28 from the third opening 33c through the fifth pipe 55. The refrigerant expands when passing through the second expansion valve 28 and is cooled to, for example, -21°C, and is supplied to the first outdoor heat exchanger 21A functioning as an evaporator through the second three-way valve 30. The refrigerant supplied to the first outdoor heat exchanger 21A is evaporated and gasified by heat exchange with the outside air (for example, -15.5°C, humidity 90%), and is supplied as a suction flow to the second inlet 32b of the second ejector 32 through the first three-way valve 29. As described above, a refrigerant at, for example, 40° C. is supplied as a driving flow from the third inlet / outlet 32a of the second ejector 32. In the second ejector 32, a refrigerant at about 40° C. and a refrigerant at about -21° C. are mixed and a refrigerant at, for example, about -16° C. in a pressurized state due to the ejector effect is supplied to the second outdoor heat exchanger 21B from the fourth inlet / outlet 32c. The refrigerant gasified by heat exchange in the second outdoor heat exchanger 21B (for example, a gas refrigerant at -16° C.) is supplied as a suction flow from the first inlet / outlet 31b of the first ejector 31.

[0075] In the case of the air conditioner 10 of this embodiment, for example, a gas refrigerant at 90°C supplied from the compressor 23 is supplied as a driving flow to the first inlet 31a of the first ejector 31, and a gas refrigerant at about -16°C that has passed through the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B is supplied as a suction flow to the first inlet 31b. As a result, a refrigerant (for example, a refrigerant at 0°C) that has been pressurized by the ejector effect and heated by mixing of the refrigerants is discharged from the second inlet 31c of the first ejector 31 and returned to the compressor 23 via the accumulator 24. In other words, even if heating operation is performed under extremely low temperature conditions such as -15°C, the pressurized and heated refrigerant is returned to the compressor 23. As a result, the operating load of the compressor 23 can be reduced compared to an air conditioner not including the first ejector 31, the second ejector 32, the first outdoor heat exchanger 21A, and the second outdoor heat exchanger 21B as in this embodiment. In other words, this contributes to reducing the power consumption of the compressor 23. In addition, the compressor 23 does not need to compress more than necessary, and the increase in refrigerant temperature due to the operation of the compressor 23 can be suppressed, thereby reducing the operating load of the compressor 23. As a result, it is possible to supply the indoor heat exchanger 41 with refrigerant for discharging hot air at a desired temperature in the indoor unit 12 while suppressing an increase in the load of the compressor 23.

[0076] Next, the defrosting operation of the air conditioner 10 will be described. As described above, the air conditioner 10 of this embodiment is configured so that defrosting is not necessary. However, snowfall or the like may cause snow to enter through the outdoor air intake port of the outdoor unit 11 and adhere to the outdoor unit 11. In such a case, a defrosting operation is temporarily performed. In the defrosting operation, the control state of each valve except for the control of the second expansion valve 28 is the same as that during the heating operation described above, and the flow of the refrigerant is also the same. In this case, the valve control unit 96 controls the second expansion valve drive circuit 87 to fully open the second expansion valve 28. In this case, the refrigerant supplied from the third opening 33c of the receiver tank 33 is not expanded by the second expansion valve 28, that is, is not cooled, and is supplied to the first outdoor heat exchanger 21A at, for example, 40°C. In other words, even if frost is attached to the first outdoor heat exchanger 21A, it can be defrosted. Furthermore, even if frost or snow has adhered to the second outdoor heat exchanger 21B, it can be defrosted (removed) by the warm refrigerant flowing through the first outdoor heat exchanger 21A. Also, since the refrigerant flows through each pipe in the same way as during heating operation, the heating operation can be continued, and non-stop heating operation can be performed.

[0077] Next, the cooling operation will be described based on the medium flow pattern shown in Fig. 6. For example, when the air conditioner 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 at the start of the cooling operation.

[0078] 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.

[0079] When the cooling operation is started, the valve control unit 96 controls the four-way valve drive circuit 84, the first three-way valve drive circuit 88, and the second three-way valve drive circuit 89 to change the direction of refrigerant flow in the four-way valve 25, the first three-way valve 29, and the second three-way valve 30 for cooling. In addition, the valve control unit 96 controls the flow control valve drive circuit 85, the first expansion valve drive circuit 86, the second expansion valve drive circuit 87, the first ejector solenoid valve drive circuit 90a, and the second ejector solenoid valve drive circuit 90b to change the open / close valve states of the flow control valve 26, the first expansion valve 27, the second expansion valve 28, the first ejector solenoid valve 61, and the second ejector solenoid valve 62 for cooling.

[0080] Specifically, the four-way valve 25 connects the third region 51c and the fifth region 51e of the first pipe 51, and connects the discharge port 23b of the compressor 23 and the second inlet / outlet 31c of the first ejector 31. At this time, the first ejector solenoid valve 61 of the first ejector 31 is fully closed. As a result, the high-temperature, high-pressure refrigerant supplied to the second inlet / outlet 31c of the first ejector 31 flows out directly from the first inlet / outlet 31b, and is supplied to the second outdoor heat exchanger 21B via the diverting sections 35a and 35c, where it is heat-exchanged with the outdoor air. At the same time, the high-temperature, high-pressure refrigerant is supplied to the first outdoor heat exchanger 21A via the diverting section 35a, the first three-way valve 29, and the diverting section 35b, where it is heat-exchanged with the outdoor air.

[0081] The refrigerant that has undergone heat exchange in the second outdoor heat exchanger 21B is supplied to the fourth inlet / outlet 32c of the second ejector 32 via the diverting sections 36c and 36a. The refrigerant that has undergone heat exchange in the first outdoor heat exchanger 21A is supplied to the fourth inlet / outlet 32c of the second ejector 32 via the diverting section 36b, the second three-way valve 30, and the diverting section 36a. At this time, the flow path is blocked by the flow path switching of the first three-way valve 29 provided in the fourth pipe 54 connected to the second inlet 32b of the second ejector 32, and the refrigerant does not flow through the fourth pipe 54. In other words, the refrigerant supplied to the fourth inlet / outlet 32c of the second ejector 32 is supplied to the receiver tank 33 as it is from the third inlet / outlet 32a of the second ejector 32 through the second opening 33b. The refrigerant stored in the receiver tank 33 is supplied from the first opening 33a to the first expansion valve 27. In this case, the fifth pipe 55 connected to the third opening 33c of the receiver tank 33 has its flow path blocked by flow path switching of the second three-way valve 30, so the refrigerant does not flow through the fifth pipe 55. In other words, the refrigerant supplied to the receiver tank 33 flows only to the first expansion valve 27 side.

[0082] The refrigerant expanded by the first expansion valve 27 and cooled is supplied to the indoor heat exchanger 41. As a result of heat exchange in the indoor heat exchanger 41, cool air can be exhausted into the room. The refrigerant discharged from the indoor heat exchanger 41 is returned to the compressor 23 via the accumulator 24.

[0083] In this way, the air conditioning apparatus 10 of this embodiment, which is capable of heating operation for cold climates, can achieve normal cooling operation during cooling operation by disabling the first ejector 31 and the second ejector 32 and using the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B in parallel.

[0084] The air conditioning device 10 according to the embodiment described above includes the indoor heat exchanger 41, the first outdoor heat exchanger 21A, the second outdoor heat exchanger 21B, the first pipe 51, the second pipe 52, the compressor 23, the four-way valve 25, the first expansion valve 27, the receiver tank 33, the third pipe 53, the flow control valve 26, the first ejector 31, the second ejector 32, the fourth pipe 54, the fifth pipe 55, and the second expansion valve 28. The indoor heat exchanger 41 is provided in the indoor unit 12. The first outdoor heat exchanger 21A is provided in the outdoor unit 11. The second outdoor heat exchanger 21B is provided in the outdoor unit 11. The first pipe 51 connects the second outdoor heat exchanger 21B and the indoor heat exchanger 41, or the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B and the indoor heat exchanger 41, and the refrigerant flows through the first pipe 51. The second pipe 52 connects the indoor heat exchanger 41 and the second outdoor heat exchanger 21B, or the indoor heat exchanger 41 and the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B, and the refrigerant flows through the first pipe 51. The compressor 23 is provided in the first pipe 51 and has an intake port 23a for sucking in the refrigerant and an outlet port 23b for discharging the refrigerant. The four-way valve 25 is provided in the first pipe 51 and can change the direction in which the refrigerant discharged from the outlet port 23b of the compressor 23 flows. The first expansion valve 27 is provided in the second pipe 52. The receiver tank 33 is provided between the first expansion valve 27 and the second outdoor heat exchanger 21B, and is capable of storing the refrigerant. The third pipe 53 connects the first pipe 51 between the indoor heat exchanger 41 and the four-way valve 25 to the first pipe 51 between the four-way valve 25 and the second outdoor heat exchanger 21B. The flow control valve 26 is provided in the third pipe 53, and controls the flow rate of the refrigerant. The first ejector 31 is provided between the four-way valve 25 of the first pipe 51 and the second outdoor heat exchanger 21B, and includes a first inlet 31a through which the refrigerant can flow from the third pipe 53, a first inlet / outlet 31b connected to the second outdoor heat exchanger 21B and through which the refrigerant can flow in and out, and a second inlet / outlet 31c connected to the four-way valve 25 and through which the refrigerant can flow in and out.The second ejector 32 includes a third inlet / outlet 32a connected to the receiver tank 33 and through which the refrigerant can flow, a second inlet 32b through which the refrigerant can flow from the first outdoor heat exchanger 21A, and a fourth inlet / outlet 32c through which the refrigerant can flow out to the second outdoor heat exchanger 21B or through which the refrigerant can flow in from the first outdoor heat exchanger 21A and the second outdoor heat exchanger 21B. A fourth pipe 54 connects the first outdoor heat exchanger 21A and the second inlet 32b of the second ejector 32. A fifth pipe 55 connects the receiver tank 33 and the first outdoor heat exchanger 21A. The second expansion valve 28 is provided in the fifth pipe 55 and expands the refrigerant to be supplied to the first outdoor heat exchanger 21A. According to this configuration, for example, the ejector effect of the first ejector 31 and the second ejector 32 makes it possible to increase the pressure and temperature of the refrigerant returned to the compressor 23 during heating operation, thereby providing an air conditioning apparatus that is capable of good heating operation even in cold regions while suppressing increases in power consumption and operating load.

[0085] Furthermore, the air conditioning device 10 may include, for example, a heat storage material 34 in the first pipe 51 between the connection portion of the third pipe 53 and the four-way valve 25. With this configuration, even if, for example, part of the high-temperature, high-pressure refrigerant discharged from the compressor 23 during heating operation is distributed to the third pipe 53 side, it is possible to supplement the temperature of the refrigerant supplied to the indoor heat exchanger 41 and contribute to maintaining the temperature of the hot air blown out from the indoor unit 12.

[0086] Furthermore, the second outdoor heat exchanger 21B of the air conditioning apparatus 10 may be disposed, for example, upstream of the first outdoor heat exchanger 21A in the flow direction of outdoor air. With this configuration, for example, it is possible to prevent outdoor air, snow, and the like from directly hitting the first outdoor heat exchanger 21A, making it easier to prevent frost from forming, and the like.

[0087] Furthermore, the first outdoor heat exchanger 21A of the air conditioning apparatus 10 may have a greater heat exchange capacity than the second outdoor heat exchanger 21B. With this configuration, for example, the heat exchange of the refrigerant can be efficiently performed during heating operation and cooling operation, which can contribute to improving the operating efficiency.

[0088] Although some 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 spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0089] 10...air conditioning device, 11...outdoor unit, 12...indoor unit, 13...refrigerant piping, 14...control device, 21...outdoor heat exchanger, 23...compressor, 24...accumulator, 25...four-way valve, 26...flow control valve, 27...first expansion valve, 28...second expansion valve, 29...first three-way valve, 30...second three-way valve, 31...first ejector, 32...second ejector, 33...receiver tank, 34...heat storage material, 41...indoor heat exchanger, 51...first piping, 52...second piping, 53...third piping, 54...fourth piping, 55...fifth piping.

Claims

1. An indoor heat exchanger provided in the indoor unit; a first outdoor heat exchanger provided in the outdoor unit; A second outdoor heat exchanger provided in the outdoor unit; a first pipe connecting the second outdoor heat exchanger and the indoor heat exchanger, or connecting the first outdoor heat exchanger and the second outdoor heat exchanger and the indoor heat exchanger, through which a refrigerant flows; a second pipe connecting the indoor heat exchanger and the second outdoor heat exchanger or connecting the indoor heat exchanger and the first outdoor heat exchanger and the second outdoor heat exchanger, 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 four-way valve provided in the first pipe and capable of changing a flow direction of the refrigerant discharged from the discharge port of the compressor; a first expansion valve provided in the second pipe; a receiver tank provided between the first expansion valve and the second outdoor heat exchanger and capable of storing the refrigerant; a third pipe connecting the first pipe between the indoor heat exchanger and the four-way valve and the first pipe between the four-way valve and the second outdoor heat exchanger; a flow control valve provided in the third pipe to control a flow rate of the refrigerant; a first ejector provided between the four-way valve and the second outdoor heat exchanger of the first piping, the first ejector including: a first inlet through which the refrigerant can flow from the third piping; a first inlet / outlet connected to the second outdoor heat exchanger through which the refrigerant can flow in and out; and a second inlet / outlet connected to the four-way valve through which the refrigerant can flow in and out; a second ejector including a third inlet / outlet connected to the receiver tank and through which the refrigerant can flow, a second inlet / outlet through which the refrigerant can flow from the first outdoor heat exchanger, and a fourth inlet / outlet through which the refrigerant can flow to the second outdoor heat exchanger or through which the refrigerant can flow from the first outdoor heat exchanger and the second outdoor heat exchanger; a fourth pipe connecting the first outdoor heat exchanger and the second inlet of the second ejector; a first three-way valve provided at a connection between the fourth pipe and the first pipe and configured to switch a flow path between a case where the refrigerant flows from the first outdoor heat exchanger to the fourth pipe and a case where the refrigerant flows from the first pipe to the first outdoor heat exchanger; a fifth pipe connecting the receiver tank and the first outdoor heat exchanger; a second expansion valve provided in the fifth pipe to expand the refrigerant to be supplied to the first outdoor heat exchanger; a second three-way valve that is provided at a connection portion between the fifth pipe and the second pipe and switches a flow path between a case where the refrigerant flows from the fifth pipe to the first outdoor heat exchanger and a case where the refrigerant flows from the first outdoor heat exchanger to the second pipe; An air conditioning device comprising:

2. The air conditioner according to claim 1 , further comprising a heat storage material in the first pipe between a connecting portion of the third pipe and the four-way valve.

3. The air-conditioning apparatus according to claim 1 , wherein the second outdoor heat exchanger is disposed upstream of the first outdoor heat exchanger in a flow direction of outdoor air.

4. The air conditioner according to claim 1 , wherein the first outdoor heat exchanger has a greater heat exchange capacity than the second outdoor heat exchanger.

Images