JP6213299B2 - Refrigeration cycle equipment - Google Patents

Description

  The present invention relates to a refrigeration cycle apparatus including a compressor having a mechanism for performing injection in a compression process.

  In a refrigeration cycle apparatus that injects an intermediate-pressure gas refrigerant into a two-stage compressor as disclosed in Patent Document 1, the two-stage compressor, a radiator, an expansion valve, and an evaporator are annularly formed by a refrigerant pipe. It is connected to the. A branching section for branching a part of the high-pressure refrigerant is provided between the radiator and the expansion valve, and an injection circuit for reducing the branched high-pressure refrigerant to an intermediate pressure and then injecting it into the compressor is provided. With this injection circuit, the temperature of the refrigerant discharged from the compressor is lowered and the power consumption of the compressor is reduced to improve the operation efficiency.

JP 2009-229055 A

  In such a refrigeration cycle apparatus, the operation efficiency of the compressor can be further improved by increasing the flow rate of the refrigerant to be injected. However, when the flow rate of the refrigerant to be injected is increased, the flow rate of the refrigerant flowing through the evaporator is reduced, so that the heat exchange amount of the evaporator may be reduced.

  Therefore, the present invention has been made in view of the above problems, and an object thereof is to secure a heat exchange amount of an evaporator and increase a flow rate of a refrigerant to be injected.

  The refrigeration cycle apparatus of the present invention is a refrigeration cycle apparatus in which a compressor having an injection port, a radiator, and an evaporator are sequentially connected in an annular manner by a refrigerant pipe, and the refrigerant flowing out from the radiator is separated into gas and liquid A gas-liquid separator that flows out the liquid refrigerant to the evaporator, an evaporator-side expansion valve that depressurizes the liquid refrigerant flowing into the evaporator, an ejector that includes a nozzle part, a suction part, and a diffuser part, and a gas-liquid separator A suction circuit for leading the gaseous refrigerant flowing out from the ejector to the nozzle part of the ejector, a suction circuit for guiding a part of the low-pressure refrigerant flowing out from the evaporator to the suction part of the ejector, and the refrigerant ejected from the diffuser part of the ejector And an injection circuit leading to the injection port of the machine.

  According to the refrigeration cycle apparatus according to the present invention, it is possible to secure the heat exchange amount of the evaporator by securing the flow rate of the refrigerant flowing through the evaporator and to increase the flow rate of the refrigerant to be injected.

It is a figure which shows the refrigerating-cycle apparatus of embodiment which concerns on this invention.

  Hereinafter, an embodiment according to the present invention will be described in detail with reference to FIG.

FIG. 1 is a diagram illustrating a refrigeration cycle apparatus 100 according to the first embodiment.
As shown in FIG. 1, in the refrigeration cycle apparatus 100 of the present embodiment, a compressor 110, a four-way valve 120, an outdoor heat exchanger 130 serving as a radiator, a gas-liquid separator 140, and a room serving as an evaporator during cooling operation. The main refrigerant circuit is configured by sequentially connecting the heat exchanger 150 and the heat exchanger 150 in an annular manner. A first refrigerant pipe 310 is provided between the discharge port 110b of the compressor 110 and the four-way valve 120, and a second refrigerant pipe 320 is provided between the four-way valve 120 and the outdoor heat exchanger 130, and the outdoor heat exchanger. 130 and the gas-liquid separator 140 are provided with a third refrigerant pipe 330, and the gas-liquid separator 140 and the indoor heat exchanger 150 are provided with a fourth refrigerant pipe 340. A fifth refrigerant pipe 350 is provided between the four-way valves 120, and a sixth refrigerant pipe 360 is provided between the four-way valve 120 and the suction port 110 a of the compressor 110.

  A first expansion valve 181 is provided in the third refrigerant pipe 330 between the outdoor heat exchanger 130 and the gas-liquid separator 140 on the main refrigerant circuit, and between the indoor heat exchanger 150 and the gas-liquid separator 140. The fourth expansion pipe 340 is provided with a second expansion valve 182. The sixth refrigerant pipe 360 between the four-way valve 120 and the suction port 110a of the compressor 110 is provided with a branch portion 160 that branches a part of the low-pressure refrigerant. A suction circuit 230 is provided that guides the gas refrigerant separated by the gas-liquid separator 140 to an ejector 170 described later, and a suction circuit 220 that guides the low-pressure refrigerant branched by the branching unit 160 to the ejector 170 described later. The suction circuit 220 may be provided with a second check valve 185 that restricts the flow of the refrigerant in one direction. The gas refrigerant separated by the gas-liquid separator 140 is sucked in through the suction circuit 230, the low-pressure refrigerant branched in the branching section 160 is sucked in through the suction circuit 220, and the gas refrigerant and the low-pressure refrigerant are mixed to increase the pressure. An ejector 170 is provided for jetting. An injection circuit 210 for injecting the refrigerant ejected from the ejector 170 into the compressor 110 is provided. The injection circuit 210 may be provided with a first check valve 184 that restricts the flow of refrigerant in one direction.

Next, each structure of the refrigerating cycle apparatus 100 of this embodiment is demonstrated.
The compressor 110 compresses the refrigerant sucked from the suction port 110a and discharges it from the discharge port 110b as a high-temperature and high-pressure refrigerant. The compressor 110 is provided with an injection port 110c for injecting a refrigerant, and an injection circuit 210 is connected to the injection port 110c. An accumulator 190 is connected to the suction port 110 a of the compressor 110, and the refrigerant is gas-liquid separated by this accumulator 190 to prevent liquid back to the compressor 110.

  The four-way valve 120 switches the direction of the refrigerant flowing in the refrigeration cycle apparatus 100 between the cooling operation and the heating operation. In the four-way valve 120, the high-temperature and high-pressure refrigerant discharged from the compressor 110 during the cooling operation flows into the outdoor heat exchanger 130, and the refrigerant that flows out of the indoor heat exchanger 160 flows into the compressor 110. Further, during the heating operation, the high-temperature and high-pressure refrigerant discharged from the compressor 110 flows into the indoor heat exchanger 160, and the refrigerant flowing out from the outdoor heat exchanger 130 flows into the compressor 110.

  The outdoor heat exchanger 130 is provided in an outdoor unit (not shown), and exchanges heat between outdoor air and refrigerant, functions as a radiator during cooling operation, and functions as an evaporator during heating operation. To do.

  The first expansion valve 181 serves to depressurize the refrigerant. The first expansion valve 181 is fully opened during the cooling operation and does not function as an expansion valve. During the heating operation, the first expansion valve 181 serves as an evaporator-side expansion valve that depressurizes the high-pressure refrigerant to the low-pressure refrigerant. Function. If the refrigerant is a supercritical refrigerant such as CO2, it functions as a radiator-side expansion valve that reduces the high-pressure refrigerant to an intermediate-pressure refrigerant during cooling operation, and the intermediate-pressure refrigerant during heating operation. It functions as an evaporator-side expansion valve that decompresses the refrigerant into a low-pressure refrigerant.

  The gas-liquid separator 140 separates the refrigerant flowing from the inlet of the gas-liquid separator 140 (142b during cooling operation, 142a during heating operation) into gas refrigerant and liquid refrigerant. The gas-liquid separator 140 is provided with a gas outlet 141 through which the separated gas refrigerant flows out and a liquid outlet through which the separated liquid refrigerant flows out (142a during cooling operation and 142b during heating operation). The gas refrigerant flowing out from the gas outlet 141 passes through a suction circuit 230 provided with a third expansion valve 183, and is sucked into an inlet 171a of a nozzle portion 171 of an ejector 170 described later. The third expansion valve 183 is for depressurizing the refrigerant, and depressurizes the passing refrigerant to an intermediate pressure refrigerant.

  The second expansion valve 182 serves to depressurize the refrigerant. The second expansion valve 182 functions as an evaporator-side expansion valve that depressurizes the high-pressure refrigerant to the low-pressure refrigerant during the cooling operation, and fully opens during the heating operation and functions as the expansion valve. do not do. When the refrigerant is a supercritical refrigerant such as CO2, it functions as an evaporator side expansion valve that reduces the intermediate pressure refrigerant to a low pressure refrigerant during the cooling operation, and the high pressure refrigerant during the heating operation. Functions as a radiator-side expansion valve that reduces the pressure to a medium-pressure refrigerant.

  The indoor heat exchanger 160 is provided in an indoor unit (not shown), and exchanges heat between indoor air and refrigerant, functions as an evaporator during cooling operation, and functions as a radiator during heating operation. To do.

  The branch portion 160 is provided at a location where the sixth refrigerant pipe 360 and the suction circuit 220 are connected, and branches a part of the low-pressure refrigerant flowing from the four-way valve 120 to the suction port 110a of the compressor 110 to the suction circuit 220.

  The ejector 170 includes a nozzle part 171, an inlet 171a of the nozzle part 171, a suction part 172, a mixing part 173, a diffuser part 174, and an outlet 174a of the diffuser part 174. The gas refrigerant flowing out from the gas-liquid separator 140 is sucked from the inlet 171a of the nozzle part 171 via the suction circuit 230. Further, the low-pressure refrigerant flowing through the suction circuit 220 is sucked from the suction unit 172. The refrigerant sucked into the nozzle part 171 and the refrigerant sucked into the suction part 172 are mixed by the mixing part 173. The mixed refrigerant is converted by the diffuser unit 174 into the velocity energy of the refrigerant into pressure energy, and the pressure of the refrigerant is increased.

  Each configuration of the ejector 170 will be described. The nozzle part 171 converts the pressure energy of the gas refrigerant flowing out from the gas-liquid separator 140 into velocity energy, and expands the refrigerant under reduced pressure. The suction part 172 sucks the refrigerant flowing through the suction circuit into the ejector 170. The mixing unit 173 mixes the refrigerant injected from the nozzle unit 171 and the refrigerant sucked from the suction unit 172 while sucking the refrigerant from the suction unit 172 by a high-speed refrigerant flow (jet flow) injected from the nozzle unit 171. It is. The diffuser portion 174 is formed in a conical taper shape so that the passage cross-sectional area increases toward the refrigerant outlet side, and converts the velocity energy of the refrigerant flowing out from the mixing portion 173 into pressure energy to increase the pressure of the refrigerant.

Next, an operation during the cooling operation of the refrigeration cycle apparatus 100 will be described.
A high-temperature and high-pressure refrigerant is discharged from the compressor 110. The discharged high-temperature and high-pressure refrigerant passes through the four-way valve 120. The refrigerant that has passed through the four-way valve 120 passes through the outdoor heat exchanger 130 that functions as a radiator, and radiates heat to the outdoor air.

  The radiated refrigerant flows into the gas-liquid separator 140 and is separated into a gas refrigerant and a liquid refrigerant. The separated gas refrigerant flows out from the gas outlet 141 of the gas-liquid separator 140 and is sucked into the inlet 171a of the nozzle portion 171 of the ejector 170 via the suction circuit 230. The separated liquid refrigerant flows out from the liquid outlet 142a of the gas-liquid separator 140.

  The liquid refrigerant that has flowed out of the gas-liquid separator 140 passes through the second expansion valve 182 that functions as an evaporator-side expansion valve, and is reduced in pressure to become a low-pressure refrigerant. The low-pressure refrigerant passes through the indoor heat exchanger 150 functioning as an evaporator and absorbs heat from the indoor air. The refrigerant that has absorbed heat is branched into two at the branching section 160 via the four-way valve 120.

  One refrigerant branched by the branch part 160 flows into the suction circuit 220 and is sucked from the suction port 172 of the ejector 170. The other refrigerant branched by the branching section 160 is returned to the suction port 110 a of the compressor 110.

  The refrigerant sucked from the inlet 171a of the nozzle part 171 of the ejector 170 and the refrigerant sucked from the suction port 172 are mixed by the mixing part 173, and the speed energy of the refrigerant is converted into pressure energy by the diffuser part 174, so that the refrigerant The pressure is increased to a medium pressure refrigerant. The pressurized refrigerant is ejected from the outlet 174a of the diffuser portion 174. The jetted refrigerant is injected into the compressor 110 via the injection circuit 210. The refrigerant circulates through each configuration described above.

  During the heating operation, the refrigerant includes the compressor 110, the four-way valve 120, the indoor heat exchanger 150 serving as a radiator, the gas-liquid separator 140, the outdoor heat exchanger 130 serving as an evaporator, the four-way valve 120, and the compressor 110. Cycle through the configuration.

  With the above operation, the refrigeration cycle apparatus 100 of the present invention branches a part of the refrigerant that has flowed out of the evaporator into an injection refrigerant, so that the flow rate of the refrigerant flowing into the evaporator is ensured and the refrigerant to be injected A flow rate can be secured.

DESCRIPTION OF SYMBOLS 100 Refrigeration cycle apparatus 110 Compressor 120 Four-way valve 130 Outdoor heat exchanger 140 Gas-liquid separator 150 Indoor heat exchanger 160 Branch part 170 Ejector 210 Injection circuit 220 Suction circuit 230 Suction circuit

Claims (1)

A refrigeration cycle apparatus in which a compressor having an injection port, a radiator, and an evaporator are sequentially connected in an annular manner by a refrigerant pipe,
A gas-liquid separator that gas-liquid separates the refrigerant flowing out of the radiator, and the liquid refrigerant flows out to the evaporator;
An evaporator-side expansion valve that depressurizes the liquid refrigerant flowing into the evaporator;
An ejector comprising a nozzle part, a suction part and a diffuser part;
A suction circuit for guiding the gas refrigerant flowing out of the gas-liquid separator to the nozzle portion of the ejector;
A suction circuit for guiding a part of the low-pressure refrigerant flowing out of the evaporator to the suction part of the ejector;
An refrigeration cycle apparatus, comprising: an injection circuit that guides refrigerant ejected from the diffuser portion of the ejector to the injection port of the compressor.

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