Refrigeration cycle device

Abstract

A refrigeration cycle device (1) comprises: a refrigerant circuit (C1) in which a refrigerant is circulated; a compressor (10) which is disposed in the refrigerant circuit (C1); an oil separator (20) which is disposed on the discharge port side of the compressor (10); an oil return flow path (R2) which returns a refrigerator oil from the oil separator (20) to the compressor (10); a first heat exchanger (30) which is connected to a refrigerant discharge port of the oil separator (20) and condenses the refrigerant, in the refrigerant circuit (C1); an expansion device (LEV1) which reduces the pressure of the refrigerant that has passed through the first heat exchanger (30); and a second heat exchanger (60) which evaporates the refrigerant that has passed through the expansion device (LEV1) and which sends the evaporated refrigerant to the compressor. In the refrigeration cycle device (1), while the compressor is being driven, the refrigerator oil is constantly stored in the oil separator (20).

Description

Refrigeration cycle equipment

[0001] The present disclosure relates to a refrigeration cycle device.

[0002] Some refrigeration cycle systems that use refrigerants are equipped with an oil return mechanism to prevent a shortage of refrigerant oil in the compressor. The oil return mechanism separates the refrigerant oil discharged from the compressor together with the refrigerant using an oil separator and returns it to the compressor.

[0003] In conventional oil return mechanisms of this type, when refrigeration oil separated from discharge gas is returned to the suction side, a pressure reducing device such as a capillary is used to minimize the inflow of discharge gas into the suction side, thereby preventing a decrease in the efficiency of the refrigeration cycle.

[0004] JP 2011-47525 A

[0005] In the oil return pipe from the oil separator, a small amount of refrigerant gas may be returned to the compressor suction pipe along with the oil. In this case, some refrigerant returns to the compressor without circulating through the refrigerant circuit (refrigerant bypass), resulting in heat and other energy losses. Furthermore, the high-temperature oil and return refrigerant raise the compressor suction temperature. In principle, an increase in the compressor suction temperature results in a loss of refrigeration cycle performance.

[0006] The refrigeration cycle device of the present disclosure is intended to solve the above-mentioned problems and has an object to improve the performance of the refrigeration cycle device.

[0007] The present disclosure relates to a refrigeration cycle device. The refrigeration cycle device includes a refrigerant circuit that circulates a refrigerant, a compressor arranged in the refrigerant circuit, an oil separator arranged in the refrigerant circuit on the discharge side of the compressor, an oil return path that returns refrigeration oil from the oil separator to the compressor, a first heat exchanger connected in the refrigerant circuit to the refrigerant discharge port of the oil separator and that condenses the refrigerant, an expansion device that decompresses the refrigerant that has passed through the first heat exchanger, and a second heat exchanger that evaporates the refrigerant that has passed through the expansion device and sends it to the compressor. In the refrigeration cycle device, a portion of the refrigeration oil is steadily stored in the oil separator when the compressor is operating.

[0008] According to the refrigeration cycle device of the present disclosure, the performance degradation due to the oil return path is suppressed, and therefore the performance of the refrigeration cycle device can be improved.

[0009] FIG. 1 is an overall configuration diagram of a refrigeration cycle apparatus of embodiment 1. FIG. 2 is a diagram of a reference example for explaining a path in which refrigerant is bypassed from an oil separator to a compressor. FIG. 3 is a diagram showing in detail the connection of the oil separator to its periphery in the refrigeration cycle apparatus of this embodiment. FIG. 4 is a reference diagram for explaining the relationship between cooling of the oil return path and air flow. FIG. 5 is a diagram showing the relationship between the temperature of the oil return pipe and the air temperature in the arrangement of FIG. 4. FIG. 6 is a diagram showing an example of a configuration in which the oil return pipe is cooled by natural convection. FIG. 7 is a diagram showing the relationship between the temperature of the oil return pipe and the air temperature in an improved configuration. FIG. 8 is a diagram showing a first modified example of a windbreak wall. FIG. 9 is a diagram showing a second modified example of a windbreak wall. FIG. 10 is a flowchart for explaining flow rate control of the oil return path.

[0010] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. While multiple embodiments will be described below, it is anticipated from the beginning that the configurations described in each embodiment will be appropriately combined. Note that identical or corresponding parts in the drawings will be designated by the same reference numerals, and their description will not be repeated.

[0011] Embodiment 1. Fig. 1 is an overall configuration diagram of a refrigeration cycle apparatus according to embodiment 1. Note that Fig. 1 functionally illustrates the connection relationships and arrangement of the devices in the refrigeration cycle apparatus 1, and does not necessarily illustrate the physical spatial arrangement.

[0012] The refrigeration cycle apparatus 1 shown in Fig. 1 includes a cold heat source unit 2, a load device 3, and extension pipes 83 and 87. The cold heat source unit 2 is usually placed outdoors and is therefore sometimes called an outdoor unit. In this embodiment, the cold heat source unit 2 operates as a cold heat source that discharges heat outdoors.

[0013] The cold heat source unit 2 of the refrigeration cycle device 1 is configured to be connected to the load device 3 by extension pipes 83 and 87 .

[0014] The cold heat source unit 2 includes a compressor 10, an oil separator 20, a first heat exchanger 30, pipes 80 to 82, 88, and a control device 100. In the first embodiment, the pipe 80 connects the discharge port of the compressor 10 to the oil separator 20. The pipe 81 connects the oil separator 20 to the first heat exchanger 30. The pipe 82 connects the first heat exchanger 30 to an extension pipe 83.

[0015] The load device 3 includes an expansion device LEV1, a second heat exchanger 60, and pipes 84, 85, and 86. The expansion device LEV1 may be, for example, a thermal expansion valve or an electronic expansion valve. Preferably, the expansion device LEV1 is a thermal expansion valve that is controlled independently of the cooling / heat source unit 2.

[0016] The refrigeration cycle apparatus 1 includes a refrigerant circuit C1. The refrigerant circuit C1 is a circulation flow path for refrigerant that runs from a pipe 88 through the compressor 10, a pipe 80, an oil separator 20, a pipe 81, a first heat exchanger 30, and a pipe 82 in this order to a refrigerant outlet of the cold heat source unit 2, and further through an extension pipe 83, a pipe 84, an expansion device LEV1, a pipe 85, a second heat exchanger 60, a pipe 86, and an extension pipe 87 before returning to the pipe 88.

[0017] The refrigeration cycle apparatus 1 further includes an oil return path R2. The oil return path R2 includes oil return pipes 91, 92 and a flow rate control device LEV2 disposed between the oil return pipes 91 and 92. The oil return pipe 91 is configured to allow refrigeration oil to flow from the oil outlet of the oil separator 20 in the circulation flow path to the flow rate control device LEV2. The oil return pipe 92 is configured to allow refrigeration oil to flow from the flow rate control device LEV2 to the suction port of the compressor 10. The oil return path R2 is a flow path that branches off from the refrigerant circuit C1 and sends refrigerant to the compressor 10 via the flow rate control device LEV2.

[0018] The compressor 10 compresses the refrigerant drawn through the pipe 88 and discharges the compressed refrigerant to the pipe 80. The compressor 10 has a suction port G1 and a discharge port G2. The compressor 10 is configured to draw in the refrigerant that has passed through the second heat exchanger 60 through the suction port G1 and discharge the compressed refrigerant from the discharge port G2 toward the first heat exchanger 30.

[0019] The flow rate adjustment device LEV2 may be, for example, an expansion valve. Preferably, the flow rate adjustment device LEV2 is an electronic expansion valve whose opening degree is changed in response to a signal provided from the control device 100.

[0020] The compressor 10 is configured to adjust the operating rotation speed Nc (also referred to as the operating frequency) in accordance with a control signal from the control device 100. By adjusting the operating rotation speed Nc of the compressor 10, the amount of refrigerant circulating is adjusted, and the refrigeration capacity of the refrigeration cycle device 1 can be adjusted. Various types of compressors 10 can be used, such as a scroll type, a rotary type, a screw type, etc.

[0021] The first heat exchanger 30 condenses the refrigerant discharged from the compressor 10 and passed through the oil separator 20, and sends the condensed refrigerant to the pipe 82. The first heat exchanger 30 is configured so that the high-temperature, high-pressure gas refrigerant discharged from the compressor 10 exchanges heat with outside air. Through this heat exchange, the gas refrigerant that has released heat condenses and changes into liquid refrigerant. A fan (not shown) supplies outside air to the first heat exchanger 30, with which the refrigerant exchanges heat in the first heat exchanger 30. The refrigerant pressure Pd on the discharge side of the compressor 10 can be adjusted by adjusting the rotation speed of the fan.

[0022] The cooling / heat source unit 2 further includes pressure sensors 160 and 161 and temperature sensors 170, 171 and 172.

[0023] The pressure sensor 160 detects the pressure Ps of the refrigerant sucked into the compressor 10 and outputs the detected value to the control device 100. The pressure sensor 161 detects the pressure Pd of the refrigerant discharged from the compressor 10 and outputs the detected value to the control device 100.

[0024] The temperature sensor 170 detects the temperature TL of the refrigerant drawn into the compressor 10 and outputs the detected value to the control device 100. The temperature sensor 171 detects the temperature TH of the refrigerant discharged from the compressor 10 and outputs the detected value to the control device 100. The temperature sensor 172 detects the temperature Ta of the outside air around the cold heat source unit 2 and outputs the detected value to the control device 100.

[0025] The control device 100 is configured to include a CPU (Central Processing Unit) 102, memory 104 (ROM (Read Only Memory) and RAM (Random Access Memory)), an input / output buffer (not shown) for inputting and outputting various signals, etc. The CPU 102 loads a program stored in the ROM into the RAM etc. and executes it. The program stored in the ROM is a program in which the processing procedures of the control device 100 are written. The control device 100 controls each device in the cooling / heat source unit 2 in accordance with these programs. This control is not limited to processing by software, but can also be processed by dedicated hardware (electronic circuitry).

[0026] CO ２ In refrigerators that use refrigerants with large differential pressures, flow control is necessary to prevent too much refrigerant from bypassing the oil return path from the oil separator.

[0027] 2 is a diagram illustrating a reference example of a bypass path for refrigerant from an oil separator to a compressor. In the reference example shown in FIG. 2, the discharge port of compressor 110 is connected to pipe 80, refrigerant and refrigerating machine oil are separated in oil separator 120, and the separated refrigerating machine oil returns to compressor 110 via a capillary tube. However, in this configuration, the flow rate of the capillary tube cannot be adjusted, so refrigerant gas often flows into the capillary tube along with the refrigerating machine oil, resulting in refrigerant bypassing compressor 110. Therefore, in this embodiment, a flow rate adjustment device LEV2 is provided in oil return path R2 to adjust the amount of oil stored in oil separator 20.

[0028] FIG. 3 is a diagram showing in detail the connections to the periphery of the oil separator in the refrigeration cycle device of this embodiment.

[0029] The control device 100 controls the opening degree of the flow rate control device LEV2 while the compressor 10 is in operation, and returns the necessary amount of refrigerating machine oil, neither too much nor too little, to the compressor 10.

[0030] In the refrigeration cycle apparatus 1, refrigeration oil is constantly stored in the oil separator 20 while the compressor is operating. Therefore, the amount of refrigeration oil sealed in the refrigerant circuit is greater than in the configuration shown in Fig. 2. If a large amount of oil is stored in the oil separator 20, it becomes difficult for refrigerant gas to enter the oil return pipe.

[0031] In the refrigeration cycle apparatus 1 of this embodiment, as shown in Figure 3, heights H1 and H2 are shown with the bottom surface of the oil separator 20 as the reference when the compressor 10 is operating. Height H1 is the liquid level of the refrigeration oil in the oil separator 20. Height H2 is the height of the oil outlet POO. Height H1 is at least higher than height H2. Furthermore, height H1 of the liquid level of the refrigeration oil is high enough to prevent refrigerant gas from being sucked in by negative pressure in the oil return path R2, so that the refrigerant gas is not discharged from the oil outlet POO.

[0032] FIG. 4 is a reference diagram illustrating the relationship between cooling in the oil return path and air flow. For example, in the refrigeration cycle device disclosed in Japanese Patent Application Laid-Open No. 2011-47525 (Patent Document 1), an oil return pipe is installed in the air path of the outdoor heat exchanger fan to cool the oil and suppress the intake temperature to avoid performance loss. However, the outdoor heat exchanger fan is generally positioned to draw air from the heat exchanger side. Therefore, if the fan, heat exchanger, and oil return pipe are arranged in this order as in Japanese Patent Application Laid-Open No. 2011-47525 (Patent Document 1), the oil return pipe would be located on the outer periphery of the housing, making it difficult to position the oil return pipe.

[0033] On the other hand, as shown in Figure 4, it is also possible to place an oil return pipe 92 between the fan 31 and the heat exchanger 30. However, even if this is done, the air reaches the oil return pipe 92 only after its temperature has risen due to the heat from the heat exchanger 30, so there is no temperature difference between the oil and the air, and it may not be possible to sufficiently cool the oil. In particular, the air temperature is high behind the condenser (downstream of the air flow). Placing the oil return pipe in this location will not provide sufficient cooling.

[0034] Figure 5 shows the relationship between the temperature of the oil return pipe and the temperature of the air in the arrangement shown in Figure 4. In particular, if there is a portion where the oil return pipe is arranged along the air flow direction, as shown in Figure 5, there will be no temperature difference downstream of the air, which may make it difficult to exchange heat between the oil return pipe and the air.

[0035] Fig. 6 is a diagram showing an example of a configuration for cooling the oil return pipe by natural convection. As shown in Fig. 6, the refrigeration cycle apparatus 1 of this embodiment includes a windbreak wall 181. As shown in Fig. 6, the windbreak wall 181 surrounds the oil return pipe 92, and is configured so that at least a portion of the surrounded wall is open.

[0036] Figure 7 shows the relationship between the temperature of the oil return pipe and the air temperature in the improved configuration. If air flows around the oil return pipe by natural convection, the temperature of the surrounding air will be warmed by the oil return pipe and move upward, replacing the unheated outside air. As shown in Figure 7, the air temperature will be constant, and heat dissipation from the oil return pipe will be promoted more than shown in Figure 5.

[0037] 8 is a diagram showing a first modified example of a windbreak wall. As shown in Fig. 8, a windbreak wall 181 surrounds the oil return pipe 92, and has slits 182 for ventilation provided in at least a portion of the surrounding area. The surface on which the slits are provided may be any of the upper, lower, side, and downwind surfaces, as long as it is not on the upwind side of the air flow generated by the fan 31.

[0038] FIG. 9 illustrates a second modified example of the windbreak wall. As shown in FIG. 9 , the refrigeration cycle apparatus 1 of this embodiment includes a fan 31 and a housing 200. The first heat exchanger 30 and at least a portion of the oil return path, the oil return pipe 92, are arranged upwind of the fan 31. A partition wall 201 is provided inside the housing 200 to separate a first air passage leading from the outside of the housing 200 to the fan 31 via the first air inlet FA and the first heat exchanger 30, and a second air passage leading from the outside of the housing 200 to the fan 31 via the second air inlet FB and the oil return pipe 92. By separating the air passages in this manner, even the air flow generated by the fan 31 can supply outside air that is not affected by the exhaust heat of the first heat exchanger 30 around the oil return pipe 92, thereby facilitating cooling of the oil return pipe 92 compared to the configuration of FIG. 4 .

[0039] Furthermore, as explained in Figure 3, if bypass of the refrigerant gas is suppressed, only refrigeration oil will flow through the oil return path, and if only oil flows, the flow rate will be very small, and the amount of heat required to be dissipated in the oil return pipe can be reduced, so the effect of using the configurations of Figures 6, 8, or 9 will be greater.

[0040] 9 shows a configuration in which the oil return pipe 92 is disposed below the first heat exchanger. However, the oil return pipe 92 may be disposed above the first heat exchanger as long as it is separated by a partition wall 201. Furthermore, the oil return pipe 92 may be disposed to the side of the first heat exchanger as long as it is separated by a partition wall 201.

[0041] The control of the flow control device LEV2 executed by the control device 100 will be described below with reference to a flowchart. FIG. 10 is a flowchart for explaining the flow control of the oil return path. When the processing of the flowchart in FIG. 10 starts, the control device 100 calculates the suction SH from the suction pressure Ps and suction temperature TL of the compressor 10 in step S1 and determines whether suction SH = 0. Alternatively, the control device 100 calculates the discharge SH from the discharge pressure Pd and discharge temperature TH of the compressor 10 in step S1 and determines whether discharge SH < 20 K. By processing step S1, the control device 100 can determine whether liquid return (liquid back), in which the compressor 10 draws liquid refrigerant, occurs.

[0042] If it is determined that liquid return has occurred (YES in S1), the control device 100 determines in step S2 whether the duration of liquid return has exceeded a determination time.

[0043] If the duration exceeds the determination time (YES in S2), the control device 100 controls the flow rate control device LEV2 in step S3 to set the oil return amount to large, thereby preventing the refrigerating machine oil from being diluted by the liquid refrigerant drawn into the compressor 10 and maintaining the reliability of the compressor 10.

[0044] On the other hand, if it is determined that there is no liquid return (NO in S1), or if the duration does not exceed the judgment time (NO in S2), the control device 100 controls the flow control device LEV2 in step S4 to set the oil return amount to small.

[0045] 10 , excess refrigeration oil may be stored in the oil separator 20 instead of the compressor 10. For example, even if liquid refrigerant returns to the compressor 10 and there is concern about dilution of the refrigeration oil, the refrigeration oil can be quickly returned from the oil separator 20 to the compressor 10, thereby preventing dilution of the refrigeration oil in the compressor 10.

[0046] While the flowchart in Fig. 10 shows an example in which the oil return rate is switched between two levels, large and small, it may be increased or decreased in multiple levels (more than two levels). However, even when the oil return rate is maximized by the processing in the flowchart in Fig. 10, as explained in Fig. 3, when the compressor 10 is operating, the refrigeration oil level H1 in the oil separator 20 is at least higher than the level H0 of the oil outlet POO. Furthermore, the opening of LEV2 is determined so that the refrigeration oil level H1 is high enough to prevent refrigerant gas from being sucked in, so that the refrigerant gas will not be discharged from the oil outlet POO even due to negative pressure from the oil return path R2.

[0047] (Summary) The above-described embodiment will be described again with reference to the drawings.

[0048] (1) The present disclosure relates to a refrigeration cycle apparatus. As shown in FIG. 1 , the refrigeration cycle apparatus 1 includes a refrigerant circuit C1 that circulates a refrigerant, a compressor 10 arranged in the refrigerant circuit C1, an oil separator 20 arranged on the discharge side of the compressor 10 in the refrigerant circuit C1, an oil return path R2 that returns refrigeration oil from the oil separator 20 to the compressor 10, a first heat exchanger 30 connected to the refrigerant discharge port of the oil separator 20 in the refrigerant circuit C1 and that condenses the refrigerant, an expansion device LEV1 that decompresses the refrigerant that has passed through the first heat exchanger 30, and a second heat exchanger 60 that evaporates the refrigerant that has passed through the expansion device LEV1 and sends the evaporated refrigerant to the compressor. In the refrigeration cycle apparatus 1, when the compressor is operating, a portion of the refrigeration oil is steadily stored in the oil separator 20.

[0049] (2) In the refrigeration cycle device described in paragraph 1, as shown in FIG. 3, when the compressor 10 is operating, the height H1 of the liquid level of the refrigeration oil in the oil separator 20 is at least higher than the height H0 of the oil discharge port POO, and is a height at which the refrigerant gas is not discharged from the oil discharge port POO.

[0050] (3) The refrigeration cycle apparatus of paragraph 1 or 2 further includes a fan 31 that is installed alongside the first heat exchanger 30 and draws air so that the air passes through the first heat exchanger 30. The fan 31 is disposed on the downwind side of the first heat exchanger 30 in the air flow generated by the fan 31. As shown in Fig. 7, the refrigeration cycle apparatus further includes a windbreak wall 181 that prevents the air that has passed through the first heat exchanger 30 from hitting at least a part of the oil return pipe 92 of the oil return path.

[0051] (4) In the refrigeration cycle apparatus described in paragraph 3, as shown in Fig. 7 or 8, the windbreak wall 181 surrounds the oil return pipe 92, and a portion of the surrounding area is open or provided with a slit 182 for ventilation. For example, one of the four windbreak walls 181 around the oil return pipe 92 is open, or one of the four windbreak walls 181 around the oil return pipe 92 is provided with a slit 182.

[0052] (5) As shown in Fig. 9, the refrigeration cycle apparatus described in paragraph 1 further includes a fan 31 that is provided adjacent to the first heat exchanger 30 and that draws air so that the air passes through the first heat exchanger 30, and a housing 200 that houses at least the fan 31, the first heat exchanger 30, and the oil return path R2. The fan 31 is disposed on the downwind side of the first heat exchanger 30 in the air flow generated by the fan 31. The first heat exchanger 30 and at least a part of the oil return pipe 92 of the oil return path R2 are disposed upwind of the fan 31. A partition wall 201 is provided inside the housing 200 to separate a first air passage that runs from the outside of the housing 200 to the fan via the first heat exchanger 30, from a second air passage that runs from the outside of the housing 200 to the fan via the oil return pipe 92.

[0053] (6) In the refrigeration cycle device according to any one of paragraphs 1 to 5, the refrigerant is CO ２An example of a refrigerant that increases compression power significantly when the suction temperature rises is CO. ２ These refrigerants have a higher specific heat ratio than, for example, R410A, and are more likely to experience loss when the intake temperature rises. Therefore, control such as that in this embodiment is expected to be highly effective in suppressing the rise in intake temperature.

[0054] (7) The refrigeration cycle device described in any one of paragraphs 1 to 6 further includes a flow control device LEV2 arranged in the oil return path R2, and a control device 100 that changes the opening degree of the flow control device LEV2 depending on the amount of liquid refrigerant returning to the compressor 10.

[0055] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present disclosure is defined by the claims, not by the description of the above embodiments, and is intended to include all modifications within the meaning and scope of the claims.

[0056] 1 Refrigeration cycle device, 2 Cold heat source unit, 3 Load device, 10 Compressor, 20 Oil separator, 30, 60 Heat exchanger, 31 Fan, 80, 81, 82, 84, 85, 86, 88 Piping, 83, 87 Extension piping, 91, 92 Oil return pipe, 100 Control device, 102 CPU, 104 Memory, 160, 161 Pressure sensor, 170, 171, 172 Temperature sensor, 181 Windbreak wall, 182 Slit, 200 Housing, 201 Partition wall, C1 Refrigerant circuit, FA, FB Intake port, G1 Intake port, G2 Discharge port, LEV1 Expansion device, LEV2 Flow rate adjustment device, R2 Oil return path.

Claims

1. A refrigeration cycle apparatus including a refrigerant circuit for circulating a refrigerant, a compressor disposed in the refrigerant circuit, an oil separator disposed on the discharge port side of the compressor in the refrigerant circuit, an oil return path for returning refrigeration oil from the oil separator to the compressor, a first heat exchanger connected to the refrigerant discharge port of the oil separator in the refrigerant circuit for condensing the refrigerant, an expansion device for decompressing the refrigerant that has passed through the first heat exchanger, and a second heat exchanger for evaporating the refrigerant that has passed through the expansion device and sending it to the compressor, wherein in a state where the compressor is operating, a part of the refrigeration oil is constantly stored in the oil separator.

2. The refrigeration cycle apparatus according to claim 1, wherein in a state where the compressor is operating, the height of the liquid level of the refrigeration oil in the oil separator is at least higher than the height of the oil discharge port and is a height at which refrigerant gas is not discharged from the oil discharge port.

3. The refrigeration cycle apparatus according to claim 1 or 2, further including a fan provided in parallel with the first heat exchanger, the fan being disposed on the leeward side of the first heat exchanger in the air flow generated by the fan, and further including a windbreak wall for preventing the air that has passed through the first heat exchanger from hitting at least a part of the oil return pipes of the oil return path.

4. The refrigeration cycle apparatus according to claim 3, wherein the windbreak wall surrounds the oil return pipe, and a part of the surrounded area is open or provided with slits for ventilation.

5. The refrigeration cycle apparatus according to claim 1, further including a fan provided in parallel with the first heat exchanger, and a housing that houses at least the fan, the first heat exchanger, and the oil return path, the fan being disposed on the leeward side of the first heat exchanger in the air flow generated by the fan, at least a part of the oil return pipes of the first heat exchanger and the oil return path being disposed above the fan in the windward direction, and a partition wall for dividing a first air passage from the outside of the housing to the fan via the first heat exchanger and a second air passage from the outside of the housing to the fan via the oil return pipe being provided inside the housing.

6. The refrigerant is a refrigerant containing CO ２ or R32, and the refrigeration cycle device according to any one of claims 1 to 5.

7. The refrigeration cycle apparatus according to any one of claims 1 to 6, further including a flow rate adjustment device disposed in the oil return path, and a control device for changing the opening degree of the flow rate adjustment device according to the amount of liquid refrigerant returned to the compressor.

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