JP2005037114A - Refrigerating cycle device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily switch cooling medium flow passages at the time of switching between a heating side and a cooling side in a refrigerating cycle using an ejector 5. <P>SOLUTION: High pressure inflow switching valves 8a, 8b and a low pressure inflow switching valve 9 which switch flow passages for a cooling medium which flows into an ejector 5 using a pressure difference therebetween are provided on the upstream sides of a high pressure inflow part 5a and a low pressure inflow part 5b, respectively, of the ejector, so that the high pressure cooling medium always flows into the high pressure inflow part 5a and the low pressure cooling medium always flows into the low pressure inflow part 5b even when a four-way valve 2 is switched. By virtue of such a simple configuration, the flow passages for the cooling medium which flows into the ejector 5 are automatically switched, so that the high pressure cooling medium always flows into the high pressure inflow part 5a and the low pressure cooling medium always flows into the low pressure inflow part 5b. Due to this, in the refrigerating cycle using the ejector 5, the switching between the heating side and the cooling side can be easily attained simply by providing the four-way valve 2 at an outlet of a compressor 1 to change the flowing direction of the cooling medium. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a refrigeration cycle apparatus using an ejector, and more particularly to a refrigeration cycle apparatus that facilitates switching of a refrigerant flow path when switching between a heating side and a cooling side.

  The switching between the heating side and the cooling side in a refrigeration cycle that does not use an ejector can be performed by using a decompression device that has a decompression function even if the refrigerant flow direction is reversed, as disclosed in Patent Document 1. It is only necessary to provide a four-way valve for changing the flow direction of the refrigerant. However, when an ejector is used to improve the efficiency of the refrigeration cycle, there are two refrigerant inflow portions on the high pressure side and the low pressure side, so the ejector will not operate simply by reversing the flow. .

As a conventional technique for switching between a heating side and a cooling side in a refrigeration cycle using such an ejector, there is one disclosed in Patent Document 2. In this system, a large number of switching means such as a three-way valve are used to switch the refrigerant flow path so as to switch between the heating side and the cooling side.
JP-A-8-254372 JP 2002-286326 A

  However, the above-described conventional technique has a problem that a large number of switching means are required and the switching means must be switched according to the operation mode, resulting in a complicated configuration and an increase in cost. The present invention has been made in view of the problems of the prior art, and its purpose is to facilitate switching of the refrigerant flow path when switching between the heating side and the cooling side in a refrigeration cycle using an ejector. An object of the present invention is to provide a refrigeration cycle apparatus.

In order to achieve the above object, the present invention employs technical means described in claims 1 to 8. That is, in the first aspect of the present invention, the compressor (1) that sucks the gas-phase refrigerant in the refrigeration cycle, pressurizes it to high pressure and discharges it, and the refrigerant flow path that is discharged from the compressor (1) are switched. Heat exchange between the four-way valve (2), the first heat exchanger (3) for exchanging heat between the refrigerant from the four-way valve (2) and the outside air, and the refrigerant and the cooled fluid from the four-way valve (2). The second heat exchanger (4) to be performed and the high-pressure refrigerant pressurized by the compressor (1) are decompressed to suck the refrigerant from the first heat exchanger (3) or the second heat exchanger (4). The ejector (5) that is mixed, pressurized and discharged, and the gas-liquid two-phase refrigerant discharged from the ejector (5) are gas-liquid separated, the gas-phase refrigerant is supplied to the compressor (1), and the liquid-phase refrigerant is the first heat. A refrigeration cycle apparatus comprising a gas-liquid separator (6) to be supplied to the exchanger (3) or the second heat exchanger (4);
High pressure inflow switching means (8a) for switching the refrigerant flow path flowing into the ejector (5) using the pressure difference of the refrigerant upstream of the high pressure inflow portion (5a) and the low pressure inflow portion (5b) of the ejector (5). 8b, 10) and a low-pressure inflow switching means (9), and the high-pressure refrigerant always flows into the high-pressure inflow portion (5a) even when the four-way valve (2) is switched, and the low-pressure refrigerant is always in the low-pressure inflow portion (5b). It is characterized by having flowed into

  According to the first aspect of the present invention, the ejector (5) has a simple configuration including the high pressure inflow switching means (8a, 8b, 10) and the low pressure inflow switching means (9) using the pressure difference of the refrigerant. ) Automatically flows into the refrigerant flow path, so that the high-pressure refrigerant always flows into the high-pressure inflow portion (5a) and the low-pressure refrigerant always flows into the low-pressure inflow portion (5b). Thus, in the refrigeration cycle using the ejector (5), just like the refrigeration cycle using the expansion valve or the like, the four-way valve (2) is provided at the outlet of the compressor (1), and the refrigerant flow direction is changed. The heating side and the cooling side can be easily switched.

According to the second aspect of the present invention, the compressor (1) that sucks the gas-phase refrigerant in the refrigeration cycle, pressurizes it to high pressure and discharges it, and the four-way switching of the refrigerant flow path discharged from the compressor (1). The heat exchange between the valve (2), the first heat exchanger (3) that exchanges heat between the refrigerant from the four-way valve (2) and the outside air, and the refrigerant and the cooled fluid from the four-way valve (2) The second heat exchanger (4) and the high-pressure refrigerant pressurized by the compressor (1) are depressurized, and the liquid-phase refrigerant from the gas-liquid separator (6) is sucked and mixed, and the pressure is increased to perform the first heat exchange. The ejector (5) discharged to the heat exchanger (3) or the second heat exchanger (4) and the refrigerant flowing out from the first heat exchanger (3) or the second heat exchanger (4) are separated into gas and liquid. In the refrigeration cycle apparatus comprising a gas-liquid separator (6) for supplying the phase refrigerant to the compressor (1) and supplying the liquid phase refrigerant to the ejector (5),
High pressure inflow switching means (10) for switching the refrigerant flow path flowing into the ejector (5) using the pressure difference of the refrigerant upstream of the high pressure inflow portion (5a) of the ejector (5), and a discharge portion of the ejector (5) When the four-way valve (2) is switched by providing low-pressure outflow switching means (9) for switching the flow path of the refrigerant flowing out from the ejector (5) using the pressure difference of the refrigerant downstream of (5f), the high-pressure refrigerant Always flows into the high pressure inflow section (5a) so that the gas-liquid two-phase refrigerant discharged from the ejector (5) flows into the first heat exchanger (3) or the second heat exchanger (4) on the low pressure side. It is characterized by that.

  In the refrigeration cycle according to the first aspect, the ejector (5) sucks the refrigerant flowing out from the first heat exchanger (3) or the second heat exchanger (4) on the low pressure side. In this configuration, when the expansion power is small, such as when the difference between high and low pressures is small, or when the flow resistance of the portion where the suction flow flows (low-pressure side heat exchanger or connecting pipe) is greater than the boosting performance of the ejector (5). Cannot flow the refrigerant flow rate required for the low pressure side (evaporation side) heat exchanger, making it difficult to operate the refrigeration cycle.

In a CO ₂ refrigerant that has been attracting attention as a de-fluorocarbon refrigerant, the pressure increase performance of the ejector (5) is 0. In contrast to the fact that it is several MPa, a CFC-based refrigerant such as R134a or R410a has a particularly high influence because the pressure increase performance is as low as 0.1 MPa or less. In addition, fluorocarbon refrigerants are generally used in room air conditioners for home use. In this refrigeration cycle, the height difference between the indoor unit and the outdoor unit is 10 m or more, the pipe length is increased, and the ejector (5 ) Is particularly susceptible to the lack of boosting performance.

  On the other hand, the refrigeration cycle of claim 2 allows the refrigerant flow driven by the compressor (1) to pass through the low-pressure side heat exchanger, and uses the ejector (5) as the refrigerant flowing into the low-pressure side heat exchanger. This is a refrigeration cycle configured to suck and inject the liquid refrigerant stored in the gas-liquid separator (6). By recirculating the refrigerant, a gas-liquid two-phase refrigerant having a high degree of dryness flows into the low-pressure side heat exchanger to improve boiling heat transfer. According to the second aspect of the present invention, the ejector (5) has a low boosting capability, a low-pressure side heat exchanger having a large flow path resistance, and a large height difference between the ejector (5) and the low-pressure side heat exchanger. Will work reliably.

  Further, with a simple configuration including a high pressure inflow switching means (10) and a low pressure outflow switching means (9) using the refrigerant pressure difference, the refrigerant flow path flowing into the ejector (5) and the low pressure side heat exchanger are provided. The refrigerant flow path is automatically switched, the high-pressure refrigerant always flows into the high-pressure inflow portion (5a), and the gas-liquid two-phase refrigerant discharged from the ejector (5) is the low-pressure side first heat exchanger ( 3) or the second heat exchanger (4). Thus, in the refrigeration cycle using the ejector (5), just like the refrigeration cycle using the expansion valve or the like, the four-way valve (2) is provided at the outlet of the compressor (1), and the refrigerant flow direction is changed. The heating side and the cooling side can be easily switched.

According to the third aspect of the present invention, the compressor (1) that sucks the gas-phase refrigerant in the refrigeration cycle, pressurizes it to high pressure and discharges it, and the four-way switching of the refrigerant flow path discharged from the compressor (1). The heat exchange between the valve (2), the first heat exchanger (3) that exchanges heat between the refrigerant from the four-way valve (2) and the outside air, and the refrigerant and the cooled fluid from the four-way valve (2) The high pressure refrigerant pressurized by the second heat exchanger (4) and the compressor (1) is depressurized and flows out of the first heat exchanger (3) or the second heat exchanger (4) on the low pressure side. In a refrigeration cycle apparatus comprising an ejector (5) that sucks, mixes, boosts pressure of a refrigerant, and discharges the refrigerant again to the first heat exchanger (3) or the second heat exchanger (4).
High pressure inflow switching means (10) for switching the refrigerant flow path flowing into the ejector (5) using the pressure difference of the refrigerant upstream of the high pressure inflow portion (5a) of the ejector (5), and a discharge portion of the ejector (5) When the four-way valve (2) is switched by providing low-pressure outflow switching means (9) for switching the flow path of the refrigerant flowing out from the ejector (5) using the pressure difference of the refrigerant downstream of (5f), the high-pressure refrigerant Always flows into the high pressure inflow section (5a) so that the gas-liquid two-phase refrigerant discharged from the ejector (5) flows into the first heat exchanger (3) or the second heat exchanger (4) on the low pressure side. It is characterized by that.

  The refrigeration cycle of claim 3 is configured by removing the gas-liquid separator (6) from the refrigeration cycle of claim 2. According to the third aspect of the invention, the same operation and effect as the refrigeration cycle of the second aspect can be obtained, and the refrigeration cycle can be configured more simply.

  In the invention according to claim 4, as the high pressure inflow switching means (8a, 8b), the refrigerant pressure on the first heat exchanger (3) side and the refrigerant pressure on the second heat exchanger (4) side are received, A first check valve (8a) that opens when the refrigerant pressure on the first heat exchanger (3) side is high, and a second valve that opens when the refrigerant pressure on the second heat exchanger (4) side is high. A high-pressure refrigerant always flows into the high-pressure inflow portion (5a) even when the four-way valve (2) is switched by using the check valve (8b) in combination.

  According to the invention described in claim 4, the high pressure inflow switching means (8a, 8b) is configured such that the high pressure refrigerant always flows into the high pressure inflow portion (5a) by combining simple check valves (8a, 8b). 8b) can be configured.

  In the fifth aspect of the invention, the low pressure inflow switching means (9) is movable by receiving the refrigerant pressure on the first heat exchanger (3) side and the refrigerant pressure on the second heat exchanger (4) side. A low pressure side differential pressure switching valve (9) provided with a valve body (92) that closes the flow path on the higher refrigerant pressure side by any high refrigerant pressure and opens the flow path on the lower refrigerant pressure side; The low-pressure refrigerant always flows into the low-pressure inflow portion (5b) even when the four-way valve (2) is switched.

  According to the fifth aspect of the present invention, by using the simple differential pressure switching valve (9) in which the valve body (92) is moved by the differential pressure and the low pressure side is communicated, the low-pressure refrigerant is always low in pressure. Low pressure inflow switching means (9) adapted to flow into the inflow portion (5b) can be provided, and the cycle configuration can be simplified.

  In the invention described in claim 6, the low-pressure outflow switching means (9) is movable by receiving the refrigerant pressure on the first heat exchanger (3) side and the refrigerant pressure on the second heat exchanger (4) side. A low pressure side differential pressure switching valve (9) provided with a valve body (92) that closes the flow path on the higher refrigerant pressure side by any high refrigerant pressure and opens the flow path on the lower refrigerant pressure side; When the four-way valve (2) is switched, the gas-liquid two-phase refrigerant discharged from the ejector (5) flows into the first heat exchanger (3) or the second heat exchanger (4) on the low pressure side. It is characterized by that.

  According to the sixth aspect of the present invention, by using the simple differential pressure switching valve (9) in which the valve body (92) is moved by the differential pressure and the low pressure side is communicated, the ejector (5) is discharged. The gas-liquid two-phase refrigerant can be low-pressure outflow switching means (9) adapted to flow into the first heat exchanger (3) or the second heat exchanger (4) on the low-pressure side. Simplification can be achieved.

  In the seventh aspect of the invention, the high pressure inflow switching means (10) is movable by receiving the refrigerant pressure on the first heat exchanger (3) side and the refrigerant pressure on the second heat exchanger (4) side. A high pressure side differential pressure switching valve (10) provided with a valve body (102) that opens a flow path on a higher refrigerant pressure side by any high refrigerant pressure and closes a flow path on a lower refrigerant pressure side. The high-pressure refrigerant always flows into the high-pressure inflow part (5a) even when the four-way valve (2) is switched.

  According to the seventh aspect of the present invention, by using the simple differential pressure switching valve (10) in which the valve body (102) is moved by the differential pressure and the high pressure side is communicated, the high pressure refrigerant always flows into the high pressure flow. It can be set as the high voltage | pressure inflow switching means (10) made to flow into a part (5a), and simplification of a cycle structure can be achieved.

  In the invention described in claim 8, the low pressure side differential pressure switching valve (9) and / or the high pressure side differential pressure switching valve (10) or both differential pressure switching valves (9, 10) are integrated with the ejector (5). It is characterized by having made it. According to the eighth aspect of the present invention, the refrigerant flow path is also formed in the housing of the ejector (5) by integrating the differential pressure switching valve (9, 10), so that the ejector (5) and the differential pressure switching valve are formed. (9, 10) can be configured in a small size, and these costs can be reduced.

  Further, the refrigerant flow path is connected to the gas-liquid separator (6) on the refrigerant discharge side in the same manner as in the cycle in which the heating side and the cooling side are fixed, and the differential pressure valve integrated ejector (50) is connected to the first heat. It is only necessary to connect between the exchanger (3) and the second heat exchanger (4). As a result, it is possible to omit connection piping and connection work between the functional components, and it is possible to reduce the cost as well as to reduce the size. Incidentally, the reference numerals in parentheses of the above means are examples showing the correspondence with the specific means described in the embodiments described later.

(First embodiment)
Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram of a refrigeration cycle apparatus according to a first embodiment of the present invention. In addition, although this embodiment demonstrates the refrigeration cycle apparatus of this invention as what is applied to the air-conditioning apparatus which heats / cools indoor air with the indoor heat exchanger 4, and heats and cools indoors, It may be water or the like, and may be applied to a device that performs hot water supply, warm storage, refrigeration, freezing, and the like.

  First, reference numeral 1 denotes a compressor that sucks gas pressure refrigerant in the refrigeration cycle, pressurizes the refrigerant to high pressure, and discharges it. Reference numeral 2 denotes a flow path of gas refrigerant discharged from the compressor 1 between heating and cooling. At the same time, it is a four-way valve that switches the flow path of the liquid refrigerant accumulated in the gas-liquid separator 6 to be described later between heating and cooling. 3 is an outdoor heat exchanger (first heat exchanger) for exchanging heat between the refrigerant from the four-way valve 2 and the outside air, and 4 is a heat exchange between the refrigerant from the four-way valve 2 and the indoor air. It is the indoor heat exchanger (2nd heat exchanger) to perform.

  Reference numeral 5 denotes an ejector that decompresses the high-pressure refrigerant pressurized by the compressor 1, sucks and mixes the refrigerant from the outdoor heat exchanger 3 or the indoor heat exchanger 4, and pressurizes and discharges the refrigerant. The gas-liquid two-phase refrigerant discharged from the gas-liquid separator is gas-liquid separated, the gas-phase refrigerant is supplied to the compressor 1, and the liquid-phase refrigerant is supplied to the outdoor heat exchanger 3 or the indoor heat exchanger 4. Reference numeral 7 denotes a throttle which depressurizes the liquid refrigerant flowing out of the gas-liquid separator 6.

  Here, the structure of the ejector 5 which is a premise of the present invention will be described with reference to a schematic cross-sectional view. The ejector 5 converts the pressure energy of the high-pressure refrigerant flowing from the high-pressure inflow portion 5a into velocity energy, and entrains the high-speed refrigerant flow ejected from the nozzle 51, which isentropically decompressed and expanded. While sucking the gas-phase refrigerant flowing in from the low-pressure inflow portion 5b by the action from the suction portion 5c, the mixing portion 5d that mixes the refrigerant flow injected from the nozzle 51, and the refrigerant injected from the nozzle 51 and the low-pressure inflow portion 5b It comprises a diffuser portion 5e, a discharge portion 5f, and the like that increase the pressure of the refrigerant by converting velocity energy into pressure energy while mixing with the refrigerant.

  At this time, in the mixing unit 5d, the driving flow and the suction flow are mixed so that the sum of the momentum of the driving flow and the momentum of the suction flow is preserved, so that the refrigerant pressure (static pressure) also exists in the mixing unit 5d. Rises. On the other hand, in the diffuser portion 5e, the velocity energy (dynamic pressure) of the refrigerant is converted into pressure energy (static pressure) by gradually increasing the cross-sectional area of the passage. Therefore, in the ejector 5, the mixing portion 5d and the diffuser portion 5e. Both increase the refrigerant pressure. Therefore, the mixing unit 5d and the diffuser unit 5e are collectively referred to as a boosting unit.

  By the way, in this embodiment, in order to accelerate the speed of the refrigerant ejected from the nozzle 51 to a sound speed or higher, a Laval nozzle having a throat portion 51a whose passage area is most reduced in the middle of the passage (see Fluid Engineering (Tokyo University Press)) Of course, it goes without saying that a tapered nozzle may be adopted.

  Next, the configuration of the main part according to the present invention in this embodiment will be described. First, in the present embodiment, high-pressure inflow switching means 8a and 8b for switching the refrigerant flow path that flows into the ejector 5 using the pressure difference of the refrigerant upstream of the high-pressure inflow portion 5a and the low-pressure inflow portion 5b of the ejector 5, respectively. Low pressure inflow switching means 9 is provided. Specifically, the high pressure inflow switching means 8a and 8b are opened when the refrigerant pressure on the outdoor heat exchanger 3 side and the refrigerant pressure on the indoor heat exchanger 4 side are received and the refrigerant pressure on the outdoor heat exchanger 3 side is high. The first check valve 8a to be valved and the second check valve 8b to be opened when the refrigerant pressure on the indoor heat exchanger 4 side is high are used in combination.

  Each check valve 8a, 8b has a structure in which a communication side inflow portion 81a and a sealing side inflow portion 81b are provided at both ends of the housing 81, and the valve body 82 faces toward the communication side inflow portion 81a. Is pressed by a spring 83. Accordingly, when the pressure from the communication side inflow portion 81a is high, the valve body 82 is pushed down to establish communication with the sealing side inflow portion 81b, and when the pressure from the sealing side inflow portion 81b is high, the valve body 82 is communicated. Sealing is performed by pressing against the side inflow portion 81a side.

  As shown in FIG. 1, the two check valves 8 a and 8 b are arranged opposite to the upstream side of the high pressure inflow portion 5 a so that the pressure of the outdoor heat exchanger 3 is higher than the pressure of the indoor heat exchanger 4. When the temperature is high, the first check valve 8a is opened to flow the refrigerant in the outdoor heat exchanger 3 to the high-pressure inflow portion 5a, and the second check valve 8b is closed to prevent backflow to the indoor heat exchanger 4. Conversely, when the pressure in the indoor heat exchanger 4 is higher than the pressure in the outdoor heat exchanger 3, the second check valve 8b is opened to allow the refrigerant in the indoor heat exchanger 4 to flow to the high-pressure inflow portion 5a. The check valve 8a is closed to prevent backflow to the outdoor heat exchanger 3.

  The low-pressure inflow switching means 9 includes a valve body 92 that is movable in response to the refrigerant pressure on the outdoor heat exchanger 3 side and the refrigerant pressure on the indoor heat exchanger 4 side. A low pressure side differential pressure switching valve 9 is used that closes the high flow path and opens the low refrigerant pressure flow path. FIG. 3 is a schematic diagram for explaining the structure of the low-pressure side differential pressure switching valve 9 in one embodiment of the present invention, and (a) is a cross-sectional view taken along line AA in (b).

  Specifically, a first inflow portion 91a and a second inflow portion 91b are provided at both ends of the housing 91, and the refrigerant flows into the outdoor heat exchanger 3 and the indoor heat exchanger 4 respectively. Further, an outflow portion 91c is provided on the central side surface of the housing 91, and communicates with the low pressure inflow portion 5b of the ejector 5 so that the low pressure refrigerant from the outdoor heat exchanger 3 or the indoor heat exchanger 4 flows out. It has become.

  91d is a valve seat, and 92 is a valve body. The high pressure side inflow portion is closed and the low pressure side inflow portion and the outflow portion 91c are communicated with each other by the differential pressure of the refrigerant flowing in from both inflow portions 91a and 91b. ing. Reference numeral 92a denotes a guide part for sliding, and a refrigerant passage 92b is provided between the guide parts 92a. Next, the refrigerant flow in each operation mode in the refrigeration cycle apparatus configured as described above will be described.

<Heating operation>
FIG. 1 shows a heating (heating) operation state in the indoor heat exchanger 4. In the following schematic cycle diagrams, the path through which the refrigerant flows is indicated by a thick line, and the path to which only pressure is applied is indicated by a thin line. In the heating mode, the high-temperature refrigerant exiting the compressor 1 is supplied to the indoor heat exchanger 4 side by the four-way valve 2. As a result, the refrigerant pressure on the indoor heat exchanger 4 side becomes higher than the refrigerant pressure on the outdoor heat exchanger 3 side, so the second check valve 8b is opened and the first check valve 8a is closed. . Further, in the low pressure side differential pressure switching valve 9, since the second inflow portion 91b side is high pressure and the first inflow portion 91a side is low pressure, the valve body 92 is pressed against the second inflow portion 91b side to close, The portion 91a and the outflow portion 91c communicate with each other.

  When each valve operates as described above, the high-temperature refrigerant exiting the compressor 1 passes through the four-way valve 2 and is radiated to the indoor air by the indoor heat exchanger 4 to be heated. Then, after passing through the second check valve 8b and entering the ejector 5 from the high pressure side inflow portion 5a and mixing with the refrigerant flowing in from the low pressure side inflow portion 5b, the gas-liquid separator 6 converts the refrigerant into a gas phase refrigerant and a liquid phase refrigerant. To be separated. Then, the gas phase refrigerant is compressed again by the compressor 1. On the other hand, the liquid refrigerant is decompressed by the throttle 7 and then reaches the outdoor heat exchanger 3 from the four-way valve 2 and absorbs heat from the outside air. Thereafter, the flow passes through the low pressure side differential pressure switching valve 9 and reaches the low pressure side inflow portion 5 b of the ejector 5.

<Cooling operation>
FIG. 4 shows a cooling (cooling) operation state in the indoor heat exchanger 4. In the cooling mode, the high-temperature refrigerant exiting the compressor 1 is supplied to the outdoor heat exchanger 3 side by the four-way valve 2. As a result, the refrigerant pressure on the outdoor heat exchanger 3 side becomes higher than the refrigerant pressure on the indoor heat exchanger 4 side, so the first check valve 8a is opened and the second check valve 8b is closed. . Further, in the low pressure side differential pressure switching valve 9, since the first inflow portion 91a side is high pressure and the second inflow portion 91b side is low pressure, the valve body 92 is pressed against the first inflow portion 91a side to close, The part 91b and the outflow part 91c communicate.

  When each valve operates as described above, the high-temperature refrigerant exiting the compressor 1 passes through the four-way valve 2 and radiates heat to the outside air on the outdoor heat exchanger 3 side. Then, after passing through the first check valve 8a and entering the ejector 5 from the high pressure side inflow portion 5a and mixing with the refrigerant flowing in from the low pressure side inflow portion 5b, the gas-liquid separator 6 converts the refrigerant into a gas phase refrigerant and a liquid phase refrigerant. To be separated. Then, the gas phase refrigerant is compressed again by the compressor 1. On the other hand, the liquid refrigerant is depressurized by the throttle 7, and then reaches the indoor heat exchanger 4 from the four-way valve 2 and absorbs heat from the room air to cool it. Thereafter, the flow passes through the low pressure side differential pressure switching valve 9 and reaches the low pressure side inflow portion 5 b of the ejector 5.

  Next, features in this embodiment will be described. First, the high pressure inflow switching means 8a and 8b and the low pressure inflow switching means for switching the refrigerant flow path flowing into the ejector 5 using the pressure difference of the refrigerant upstream of the high pressure inflow portion 5a and the low pressure inflow portion 5b of the ejector 5, respectively. 9 so that the high-pressure refrigerant always flows into the high-pressure inflow portion 5a and the low-pressure refrigerant always flows into the low-pressure inflow portion 5b even when the four-way valve 2 is switched.

  Thereby, the refrigerant flow path flowing into the ejector 5 is automatically switched with a simple configuration in which the high pressure inflow switching means 8a and 8b and the low pressure inflow switching means 9 using the pressure difference of the refrigerant are provided. The low-pressure refrigerant always flows into the high-pressure inflow portion 5a, and the low-pressure refrigerant always flows into the low-pressure inflow portion 5b. As a result, in the refrigeration cycle using the ejector 5, similarly to the refrigeration cycle using an expansion valve or the like, the four-way valve 2 is provided at the outlet of the compressor 1 and the refrigerant can be easily cooled by simply changing the flow direction of the refrigerant. Can be switched to the other side.

  The high pressure inflow switching means 8a and 8b are opened when the refrigerant pressure on the outdoor heat exchanger 3 side and the refrigerant pressure on the indoor heat exchanger 4 side are received and the refrigerant pressure on the outdoor heat exchanger 3 side is high. Even if the first check valve 8a and the second check valve 8b that opens when the refrigerant pressure on the indoor heat exchanger 4 side is high are used in combination, and the four-way valve 2 is switched, the high-pressure refrigerant is always in the high-pressure inflow section. It flows into 5a. Thus, by combining the simple check valves 8a and 8b, the high-pressure inflow switching means 8a and 8b can be configured such that the high-pressure refrigerant always flows into the high-pressure inflow portion 5a.

  The low-pressure inflow switching means 9 includes a valve body 92 that is movable in response to the refrigerant pressure on the outdoor heat exchanger 3 side and the refrigerant pressure on the indoor heat exchanger 4 side. Even when the four-way valve 2 is switched using the low pressure side differential pressure switching valve 9 that closes the high flow path and opens the low refrigerant pressure flow path, the low pressure refrigerant always flows into the low pressure inflow portion 5b. Like to do. Thus, by using the simple differential pressure switching valve 9 in which the valve body 92 is moved by the differential pressure to communicate the low pressure side, the low pressure inflow switching means is configured so that the low pressure refrigerant always flows into the low pressure inflow portion 5b. The cycle configuration can be simplified.

(Second Embodiment)
FIG. 5 is a schematic diagram of a refrigeration cycle apparatus according to the second embodiment of the present invention. Only the structure of the high pressure inflow switching means 10 provided upstream of the high pressure inflow portion 5a of the ejector 5 is different from the first embodiment described above. In the present embodiment, the high-pressure inflow switching means 10 includes a valve body 102 that is movable in response to the refrigerant pressure on the outdoor heat exchanger 3 side and the refrigerant pressure on the indoor heat exchanger 4 side. A high pressure side differential pressure switching valve 10 is used that opens the flow path on the high pressure side and closes the flow path on the low refrigerant pressure side.

  FIG. 6 is a schematic cross-sectional view illustrating the structure of the high-pressure side differential pressure switching valve 10 in one embodiment of the present invention. Specifically, a first inflow portion 101a and a second inflow portion 101b are provided at both ends of the housing 101, and the refrigerant flows into the outdoor heat exchanger 3 and the indoor heat exchanger 4 respectively. Further, an outflow portion 101c is provided on the central side surface of the housing 101 and communicates with the high pressure inflow portion 5a of the ejector 5 so that the high pressure refrigerant from the outdoor heat exchanger 3 or the indoor heat exchanger 4 flows out. It has become.

  A spherical valve body 102 is configured to open the high-pressure side inflow portion and communicate with the outflow portion 101c and close the low-pressure side inflow portion by the differential pressure of the refrigerant flowing in from both inflow portions 101a and 101b. Next, the refrigerant flow in each operation mode in the refrigeration cycle apparatus configured as described above will be described.

<Heating operation>
FIG. 5 shows a heating (heating) operation state in the indoor heat exchanger 4. In the heating mode, the high-temperature refrigerant exiting the compressor 1 is supplied to the indoor heat exchanger 4 side by the four-way valve 2. Accordingly, the refrigerant pressure on the indoor heat exchanger 4 side becomes higher than the refrigerant pressure on the outdoor heat exchanger 3 side. Therefore, in the high-pressure side differential pressure switching valve 10, the first inflow portion 101a side has a high pressure and the second inflow Since the part 101b side becomes a low pressure, the valve body 102 is pressed and closed to the second inflow part 101b side, and the first inflow part 101a and the outflow part 101c communicate with each other. Further, in the low pressure side differential pressure switching valve 9, since the second inflow portion 91b side is high pressure and the first inflow portion 91a side is low pressure, the valve body 92 is pressed against the second inflow portion 91b side to close, The portion 91a and the outflow portion 91c communicate with each other.

  When each valve operates as described above, the high-temperature refrigerant exiting the compressor 1 passes through the four-way valve 2 and is radiated to the indoor air by the indoor heat exchanger 4 to be heated. Then, after passing through the high-pressure side differential pressure switching valve 10 and entering the ejector 5 from the high-pressure side inflow portion 5a and mixing with the refrigerant flowing in from the low-pressure side inflow portion 5b, the gas-liquid separator 6 and the gas-phase refrigerant and liquid-phase refrigerant are mixed. Separated. Then, the gas phase refrigerant is compressed again by the compressor 1. On the other hand, the liquid refrigerant is decompressed by the throttle 7 and then reaches the outdoor heat exchanger 3 from the four-way valve 2 and absorbs heat from the outside air. Thereafter, the flow passes through the low pressure side differential pressure switching valve 9 and reaches the low pressure side inflow portion 5 b of the ejector 5.

<Cooling operation>
FIG. 7 shows a cooling (cooling) operation state in the indoor heat exchanger 4. In the cooling mode, the high-temperature refrigerant exiting the compressor 1 is supplied to the outdoor heat exchanger 3 side by the four-way valve 2. Accordingly, the refrigerant pressure on the outdoor heat exchanger 3 side becomes higher than the refrigerant pressure on the indoor heat exchanger 4 side. Therefore, in the high-pressure side differential pressure switching valve 10, the second inflow portion 101b side has a high pressure and the first inflow Since the part 101a side becomes a low pressure, the valve body 102 is pressed and closed to the first inflow part 101a side, and the first inflow part 101a and the outflow part 101c communicate with each other. Further, in the low pressure side differential pressure switching valve 9, since the first inflow portion 91a side is high pressure and the second inflow portion 91b side is low pressure, the valve body 92 is pressed against the first inflow portion 91a side to close, The part 91b and the outflow part 91c communicate.

  When each valve operates as described above, the high-temperature refrigerant exiting the compressor 1 passes through the four-way valve 2 and radiates heat to the outside air on the outdoor heat exchanger 3 side. Then, after passing through the high-pressure side differential pressure switching valve 10 and entering the ejector 5 from the high-pressure side inflow portion 5a and mixing with the refrigerant flowing in from the low-pressure side inflow portion 5b, the gas-liquid separator 6 and the gas-phase refrigerant and liquid-phase refrigerant are mixed. Separated. Then, the gas phase refrigerant is compressed again by the compressor 1. On the other hand, the liquid refrigerant is depressurized by the throttle 7, and then reaches the indoor heat exchanger 4 from the four-way valve 2 and absorbs heat from the room air to cool it. Thereafter, the flow passes through the low pressure side differential pressure switching valve 9 and reaches the low pressure side inflow portion 5 b of the ejector 5.

  Next, features in this embodiment will be described. The high-pressure inflow switching means 10 includes a valve body 102 that is movable in response to the refrigerant pressure on the outdoor heat exchanger 3 side and the refrigerant pressure on the indoor heat exchanger 4 side. Even when the four-way valve 2 is switched, the high-pressure refrigerant always flows into the high-pressure inflow portion 5a using the high-pressure side differential pressure switching valve 10 that opens the flow path of the refrigerant and closes the flow path on the low refrigerant pressure side. ing. Thus, by using the simple differential pressure switching valve 10 in which the valve body 102 is moved by the differential pressure and the high pressure side is communicated, the high pressure inflow switching means is configured so that the high pressure refrigerant always flows into the high pressure inflow portion 5a. The cycle configuration can be simplified.

(Third embodiment)
FIG. 8 is a schematic diagram of a refrigeration cycle apparatus according to the third embodiment of the present invention. In the refrigeration cycle of the first and second embodiments described above, the ejector 5 sucks the refrigerant flowing out of the outdoor heat exchanger 3 or the indoor heat exchanger 4 on the low pressure side. In this configuration, when the expansion power is small, such as when the high-low pressure difference is small, or when the flow resistance of the portion where the suction flow flows (low-pressure side heat exchanger or connection pipe) is larger than the boosting performance of the ejector 5, the low pressure The refrigerant flow required for the side (evaporation side) heat exchanger cannot be flowed, and the operation of the refrigeration cycle becomes difficult.

With a CO ₂ refrigerant that has been attracting attention as a de-fluorocarbon refrigerant, the pressurization performance of the ejector 5 is 0. In contrast to the fact that it is several MPa, a CFC-based refrigerant such as R134a or R410a has a particularly high influence because the pressure increase performance is as low as 0.1 MPa or less. In addition, chlorofluorocarbon refrigerants are generally used in room air conditioners for home use. In this refrigeration cycle, the height difference between the indoor unit and the outdoor unit is 10 m or more, the pipe length is long, and the ejector 5 Insufficient boosting performance is particularly susceptible.

  In contrast, the refrigeration cycle of the present embodiment allows the refrigerant flow driven by the compressor 1 to pass through the low-pressure side heat exchanger, and uses the ejector 5 for the refrigerant flowing into the low-pressure side heat exchanger to perform gas-liquid separation. This is a refrigeration cycle configured to suck and inject liquid phase refrigerant stored in the vessel 6. By recirculating the refrigerant, a gas-liquid two-phase refrigerant having a high degree of dryness flows into the low-pressure side heat exchanger to improve boiling heat transfer.

  Considering the energy balance of inflow / outflow in the gas-liquid separator 6, in a steady state, the flow rate of the inflowing gas phase / liquid phase refrigerant must match the outflow of the gas phase / liquid phase refrigerant. When only the gas-phase refrigerant flows out into the compressor 1 and only the liquid-phase refrigerant flows out into the ejector 5, the flow rate of the liquid-phase refrigerant flowing into the gas-liquid separator 6 is the flow rate of the liquid-phase refrigerant flowing out toward the ejector 5. Matches. That is, the dryness of the refrigerant flowing in the low-pressure side heat exchanger, which is the evaporator, is reduced by the amount of the liquid-phase refrigerant sucked by the ejector 5, and the flow rate is increased by increasing the refrigerant flow rate.

  The heat transfer coefficient of the refrigerant is higher for the liquid phase refrigerant than for the gas phase refrigerant, and the higher the flow rate, the thinner the temperature boundary layer and the higher the heat transfer coefficient. As a result, the temperature difference between the fluid that exchanges heat with the low-pressure side heat exchanger (in the case of this embodiment, air) is reduced, and the internal pressure of the low-pressure side heat exchanger is increased. Therefore, the suction pressure of the compressor 1 is increased, the compression power is reduced, and the COP can be improved.

  Further, when the difference between the high and low pressures of the refrigeration cycle is small and the boosting capacity of the ejector 5 is weak, the distance between the indoor heat exchanger 4 and the ejector 5 or the gas-liquid separator 6 is long, or the indoor heat exchanger 4 is high. Even if the refrigeration cycle of the first and second embodiments does not allow the ejector 5 to flow a sufficient refrigerant flow rate to the indoor heat exchanger 4, according to the present embodiment, the indoor heat exchanger 4 is Since the flowing refrigerant can be driven by the compressor 1, the liquid refrigerant flow sucked by the ejector 5 is only reduced, so that it does not fall into a situation where it cannot be operated as a cycle. Next, the refrigerant flow in each operation mode in the refrigeration cycle apparatus configured as described above will be described.

<Heating operation>
FIG. 8 shows a heating (heating) operation state in the indoor heat exchanger 4. In the heating mode, the high-temperature refrigerant exiting the compressor 1 is supplied to the indoor heat exchanger 4 side by the four-way valve 2. Accordingly, the refrigerant pressure on the indoor heat exchanger 4 side becomes higher than the refrigerant pressure on the outdoor heat exchanger 3 side. Therefore, in the high-pressure side differential pressure switching valve 10, the first inflow portion 101a side has a high pressure and the second inflow Since the part 101b side becomes low pressure, the valve body 102 is pressed against the second inflow part 101b side (outdoor heat exchanger 3 side) and closed, and the first inflow part 101a (indoor heat exchanger 4 side), the outflow part 101c, Communicate.

  Further, in the low pressure side differential pressure switching valve 9, the relationship between the inflow / outflow is opposite to that in the first and second embodiments, the first outflow portion 91a side is at a high pressure, and the second outflow portion 91b side is at a low pressure. 92 is pressed and closed to the first outflow part 91a (indoor heat exchanger 4 side) side, and the inflow part 91c and the second outflow part 91b (outdoor heat exchanger 3 side) communicate with each other.

  When each valve operates as described above, the high-temperature refrigerant exiting the compressor 1 passes through the four-way valve 2 and is radiated to the indoor air by the indoor heat exchanger 4 to be heated. Thereafter, the refrigerant passes through the high-pressure side differential pressure switching valve 10 and enters the ejector 5 from the high-pressure side inflow portion 5a, and the liquid-phase refrigerant stored in the gas-liquid separator 6 is sucked from the low-pressure side inflow portion 5b to be mixed and pressurized. Then, the refrigerant discharged from the discharge unit 5f passes through the low pressure side differential pressure switching valve 9, reaches the outdoor heat exchanger 3, and absorbs heat from the outside air. Thereafter, the gas-liquid separator 6 separates the gas-phase refrigerant and the liquid-phase refrigerant again through the four-way valve 2, and the gas-phase refrigerant is compressed again by the compressor 1, while the liquid-phase refrigerant is in the low pressure side inflow portion of the ejector 5. Suctioned to 5b.

<Cooling operation>
FIG. 9 shows a cooling (cooling) operation state in the indoor heat exchanger 4. In the cooling mode, the high-temperature refrigerant exiting the compressor 1 is supplied to the outdoor heat exchanger 3 side by the four-way valve 2. Accordingly, the refrigerant pressure on the outdoor heat exchanger 3 side becomes higher than the refrigerant pressure on the indoor heat exchanger 4 side. Therefore, in the high-pressure side differential pressure switching valve 10, the second inflow portion 101b side has a high pressure and the first inflow Since the part 101a side becomes a low pressure, the valve body 102 is pressed and closed to the first inflow part 101a side (indoor heat exchanger 4 side), the second inflow part 101b (outdoor heat exchanger 3 side), the outflow part 101c, Communicate.

  Further, in the low pressure side differential pressure switching valve 9, since the first outflow portion 91a side is low pressure and the second outflow portion 91b side is high pressure, the valve body 92 is on the second outflow portion 91b side (outdoor heat exchanger 3 side). The first outflow portion 91b (inside the indoor heat exchanger 4) and the inflow portion 91c communicate with each other by being pressed and closed.

  When each valve operates as described above, the high-temperature refrigerant exiting the compressor 1 passes through the four-way valve 2 and radiates heat to the outside air on the outdoor heat exchanger 3 side. Thereafter, the refrigerant passes through the high-pressure side differential pressure switching valve 10 and enters the ejector 5 from the high-pressure side inflow portion 5a, and the liquid-phase refrigerant stored in the gas-liquid separator 6 is sucked from the low-pressure side inflow portion 5b to be mixed and pressurized. Then, the refrigerant discharged from the discharge part 5f passes through the low pressure side differential pressure switching valve 9, reaches the indoor heat exchanger 4, and absorbs heat from the room air to cool it. Thereafter, the gas-liquid separator 6 separates the gas-phase refrigerant and the liquid-phase refrigerant again through the four-way valve 2, and the gas-phase refrigerant is compressed again by the compressor 1, while the liquid-phase refrigerant is in the low pressure side inflow portion of the ejector 5. Suctioned to 5b.

  Next, features in this embodiment will be described. A high pressure side differential pressure switching valve 10 that switches a refrigerant flow path that flows into the ejector 5 using a pressure difference of the refrigerant upstream of the high pressure inflow portion 5a of the ejector 5, and a refrigerant pressure difference downstream of the outflow portion 5f of the ejector 5 When the four-way valve 2 is switched by providing a low pressure side differential pressure switching valve 9 that switches the flow path of the refrigerant that has flowed out of the ejector 5 by using the high pressure refrigerant, the high pressure refrigerant always flows into the high pressure inflow portion 5a, and the ejector 5 discharges The gas-liquid two-phase refrigerant to flow into the outdoor heat exchanger 3 or the indoor heat exchanger 4 on the low pressure side. According to this, even if the ejector 5 has a low boosting capability, the flow resistance of the low-pressure side heat exchanger or the height difference between the ejector 5 and the low-pressure side heat exchanger is surely operated.

  Further, with a simple configuration provided with a high-pressure side differential pressure switching valve 10 and a low-pressure side differential pressure switching valve 9 utilizing the pressure difference of the refrigerant, the refrigerant flows into the ejector 5 and flows out to the low-pressure side heat exchanger. The refrigerant flow automatically switches, the high-pressure refrigerant always flows into the high-pressure inflow portion 5a, and the gas-liquid two-phase refrigerant discharged from the ejector 5 enters the outdoor heat exchanger 3 or the indoor heat exchanger 4 on the low pressure side. Inflow. As a result, in the refrigeration cycle using the ejector 5, similarly to the refrigeration cycle using an expansion valve or the like, the four-way valve 2 is provided at the outlet of the compressor 1 and the refrigerant can be easily cooled by simply changing the refrigerant flow direction. Can be switched to the other side.

(Fourth embodiment)
FIG. 10 is a schematic diagram of the refrigeration cycle apparatus according to the fourth embodiment of the present invention, and shows a heating operation state in the indoor heat exchanger 4. FIG. 11 shows a cooling operation state in the indoor heat exchanger 4 in the refrigeration cycle apparatus of FIG. The refrigeration cycle of the present embodiment is configured by removing the gas-liquid separator 6 from the refrigeration cycle of the third embodiment. Also with this configuration, the same operation and effect as the refrigeration cycle of the third embodiment can be obtained, and the refrigeration cycle can be configured more simply.

(Fifth embodiment)
FIG. 12 is a schematic cross-sectional view illustrating the structure of the selector valve integrated ejector 50 according to the fifth embodiment of the present invention. This is because the low pressure side differential pressure switching valve 9, the high pressure side differential pressure switching valve 10, or both of the differential pressure switching valves 9, 10 described in the first and second embodiments are placed in the main body housing of the ejector 5. It is constructed integrally.

  The first inflow portion 50 a communicating with the outdoor heat exchanger 3 branches inside and communicates with the first inflow portion 91 a of the low pressure side differential pressure switching valve 9 and the second inflow portion 101 b of the high pressure side differential pressure switching valve 10. is doing. In addition, the second inflow portion 50 b communicating with the indoor heat exchanger 4 is branched inside to the second inflow portion 91 b of the low pressure side differential pressure switching valve 9 and the first inflow portion 101 a of the high pressure side differential pressure switching valve 10. Communicating with The outflow portion 91 c of the low pressure side differential pressure switching valve 9 communicates with the low pressure side inflow portion 5 b of the ejector 5, and the outflow portion 101 c of the high pressure side differential pressure switching valve 10 communicates with the low pressure side inflow portion 5 a of the ejector 5. is doing.

  Reference numerals 92 and 102 denote valve bodies that are operated by the differential pressure of the refrigerant flowing in from both the inflow portions. FIG. 13 is a schematic diagram of a refrigeration cycle apparatus using the selector valve integrated ejector 50 of FIG. 12, and shows a cooling operation state in the indoor heat exchanger 4. Since the operation is the same as in the first and second embodiments described above, a description thereof will be omitted.

  Next, features in this embodiment will be described. A low pressure side differential pressure switching valve 9, a high pressure side differential pressure switching valve 10, or both differential pressure switching valves 9, 10 are integrally formed in the ejector 5. Thus, by forming the differential pressure switching valves 9 and 10 together with the refrigerant flow path in the housing of the ejector 5, the ejector 5 and the differential pressure switching valves 9 and 10 can be configured in a small size, and their costs are also reduced. Can be suppressed.

  Similarly to the cycle in which the refrigerant flow path is fixed on the heating side and the cooling side, the refrigerant discharge side is connected to the gas-liquid separator 6, and the differential pressure valve integrated ejector 50 is connected to the outdoor heat exchanger 3 and the indoor heat exchanger 3. Simply connecting to the heat exchanger 4 is sufficient. As a result, it is possible to omit connection piping and connection work between the functional components, and it is possible to reduce the cost as well as to reduce the size.

(Other embodiments)
In the first embodiment described above, the first check valve 8a and the second check valve 8b are combined to form the high pressure inflow switching means. Of course, the first check valve 8a and the second check valve 8a are combined. The valve 8b may be integrated to form two inflow portions, two valve body portions, and one outflow portion in one housing. Further, the valve body 102 of the high-pressure side differential pressure switching valve 10 is not limited to a spherical shape, and may be, for example, a cylindrical shape.

It is a schematic diagram of the refrigeration cycle apparatus in 1st Embodiment of this invention, and represents the heating operation state in the indoor heat exchanger 4. FIG. It is a cross-sectional schematic diagram explaining the structure of the ejector 5. FIG. It is a schematic diagram explaining the structure of the low pressure side differential pressure switching valve 9 in one Embodiment of this invention, (a) is AA sectional drawing in (b). The cooling operation state in the indoor heat exchanger 4 in the refrigeration cycle apparatus of FIG. 1 is represented. It is a schematic diagram of the refrigerating cycle device in 2nd Embodiment of this invention, and represents the heating operation state in the indoor heat exchanger 4. FIG. It is a cross-sectional schematic diagram explaining the structure of the high pressure side differential pressure switching valve 10 in one Embodiment of this invention. The cooling operation state in the indoor heat exchanger 4 in the refrigeration cycle apparatus of FIG. 5 is represented. It is a schematic diagram of the refrigerating cycle device in 3rd Embodiment of this invention, and the heating operation state in the indoor heat exchanger 4 is represented. The cooling operation state in the indoor heat exchanger 4 in the refrigeration cycle apparatus of FIG. 8 is represented. It is a schematic diagram of the refrigeration cycle apparatus in 4th Embodiment of this invention, and the heating operation state in the indoor heat exchanger 4 is represented. The cooling operation state in the indoor heat exchanger 4 in the refrigeration cycle apparatus of FIG. 10 is represented. It is a cross-sectional schematic diagram explaining the structure of the switching valve integrated ejector 50 in 5th Embodiment of this invention. FIG. 13 is a schematic diagram of a refrigeration cycle apparatus using the switching valve integrated ejector 50 of FIG. 12, and represents a cooling operation state in the indoor heat exchanger 4.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Compressor 2 ... Four-way valve 3 ... Outdoor heat exchanger (1st heat exchanger)
4 ... Indoor heat exchanger (second heat exchanger)
DESCRIPTION OF SYMBOLS 5 ... Ejector 5a ... High pressure inflow part 5b ... Low pressure inflow part 5f ... Discharge part 6 ... Gas-liquid separator 8a ... 1st check valve (high pressure inflow switching means)
8b ... Second check valve (high pressure inflow switching means)
9 ... Low pressure side differential pressure switching valve (low pressure inflow switching means, low pressure outflow switching means)
10 ... High pressure side differential pressure switching valve (High pressure inflow switching means)
92 ... Valve 102 ... Valve

Claims (8)

A compressor (1) for sucking in a gas-phase refrigerant in the refrigeration cycle, pressurizing it to a high pressure and discharging it;
A four-way valve (2) for switching the flow path of the refrigerant discharged from the compressor (1);
A first heat exchanger (3) for exchanging heat between the refrigerant from the four-way valve (2) and the outside air;
A second heat exchanger (4) for exchanging heat between the refrigerant from the four-way valve (2) and the cooled heat fluid;
An ejector that depressurizes the high-pressure refrigerant pressurized by the compressor (1), sucks and mixes the refrigerant from the first heat exchanger (3) or the second heat exchanger (4), and pressurizes and discharges the refrigerant. (5) and
The gas-liquid two-phase refrigerant discharged from the ejector (5) is gas-liquid separated, the gas-phase refrigerant is supplied to the compressor (1), and the liquid-phase refrigerant is the first heat exchanger (3) or the second heat. A refrigeration cycle apparatus comprising a gas-liquid separator (6) to be supplied to the exchanger (4),
High pressure inflow switching means for switching the refrigerant flow path flowing into the ejector (5) using the pressure difference of the refrigerant upstream of the high pressure inflow portion (5a) and the low pressure inflow portion (5b) of the ejector (5). (8a, 8b, 10) and low-pressure inflow switching means (9) are provided, and even when the four-way valve (2) is switched, the high-pressure refrigerant always flows into the high-pressure inflow portion (5a), and the low-pressure refrigerant is always in the low pressure A refrigeration cycle apparatus characterized by flowing into the inflow portion (5b). A compressor (1) for sucking in a gas-phase refrigerant in the refrigeration cycle, pressurizing it to a high pressure and discharging it;
A four-way valve (2) for switching the flow path of the refrigerant discharged from the compressor (1);
A first heat exchanger (3) for exchanging heat between the refrigerant from the four-way valve (2) and the outside air;
A second heat exchanger (4) for exchanging heat between the refrigerant from the four-way valve (2) and the cooled heat fluid;
The high-pressure refrigerant pressurized by the compressor (1) is depressurized, the liquid-phase refrigerant from the gas-liquid separator (6) is sucked and mixed, and the pressure is increased to increase the first heat exchanger (3) or the second An ejector (5) for discharging to the heat exchanger (4);
The refrigerant flowing out of the first heat exchanger (3) or the second heat exchanger (4) is gas-liquid separated, the gas-phase refrigerant is supplied to the compressor (1), and the liquid-phase refrigerant is the ejector (5). In the refrigeration cycle apparatus comprising the gas-liquid separator (6) supplied to
High pressure inflow switching means (10) for switching the refrigerant flow path flowing into the ejector (5) using the pressure difference of the refrigerant upstream of the high pressure inflow portion (5a) of the ejector (5), and the ejector (5) And a low-pressure outflow switching means (9) for switching the flow path of the refrigerant that has flowed out of the ejector (5) using the refrigerant pressure difference downstream of the discharge section (5f), and switching the four-way valve (2) In this case, the high-pressure refrigerant always flows into the high-pressure inflow portion (5a), and the gas-liquid two-phase refrigerant discharged from the ejector (5) is the first heat exchanger (3) or the second heat that is on the low-pressure side. A refrigeration cycle apparatus characterized by flowing into the exchanger (4). A compressor (1) for sucking in a gas-phase refrigerant in the refrigeration cycle, pressurizing it to a high pressure and discharging it;
A four-way valve (2) for switching the flow path of the refrigerant discharged from the compressor (1);
A first heat exchanger (3) for exchanging heat between the refrigerant from the four-way valve (2) and the outside air;
A second heat exchanger (4) for exchanging heat between the refrigerant from the four-way valve (2) and the cooled heat fluid;
The high-pressure refrigerant pressurized by the compressor (1) is depressurized and a part of the refrigerant flowing out from the first heat exchanger (3) or the second heat exchanger (4) on the low pressure side is sucked. In a refrigeration cycle apparatus comprising an ejector (5) that is mixed, boosted and discharged again to the first heat exchanger (3) or the second heat exchanger (4),
High pressure inflow switching means (10) for switching the refrigerant flow path flowing into the ejector (5) using the pressure difference of the refrigerant upstream of the high pressure inflow portion (5a) of the ejector (5), and the ejector (5) And a low-pressure outflow switching means (9) for switching the flow path of the refrigerant that has flowed out of the ejector (5) using the refrigerant pressure difference downstream of the discharge section (5f), and switching the four-way valve (2) Even in this case, the high-pressure refrigerant always flows into the high-pressure inflow portion (5a), and the gas-liquid two-phase refrigerant discharged from the ejector (5) is the first heat exchanger (3) or the second heat exchange on the low-pressure side. A refrigeration cycle apparatus characterized in that it flows into the vessel (4).   The high-pressure inflow switching means (8a, 8b) receives the refrigerant pressure on the first heat exchanger (3) side and the refrigerant pressure on the second heat exchanger (4) side, and receives the first heat exchanger ( 3) a first check valve (8a) that opens when the refrigerant pressure on the side is high, and a second check valve (8b) that opens when the refrigerant pressure on the second heat exchanger (4) side is high. 2), the high-pressure refrigerant always flows into the high-pressure inflow portion (5a) even when the four-way valve (2) is switched.   The low-pressure inflow switching means (9) includes a valve body (92) that is movable in response to the refrigerant pressure on the first heat exchanger (3) side and the refrigerant pressure on the second heat exchanger (4) side. The low pressure side differential pressure switching valve (9) is used to close the flow path on the higher refrigerant pressure side and open the flow path on the lower refrigerant pressure side by any high refrigerant pressure, and the four-way valve (2 2), the low-pressure refrigerant always flows into the low-pressure inflow portion (5b).   The low-pressure outflow switching means (9) includes a valve body (92) that is movable in response to the refrigerant pressure on the first heat exchanger (3) side and the refrigerant pressure on the second heat exchanger (4) side. The low pressure side differential pressure switching valve (9) is used to close the flow path on the higher refrigerant pressure side and open the flow path on the lower refrigerant pressure side by any high refrigerant pressure, and the four-way valve (2 ), The gas-liquid two-phase refrigerant discharged from the ejector (5) flows into the first heat exchanger (3) or the second heat exchanger (4) on the low pressure side. The refrigeration cycle apparatus according to claim 2 or claim 3, wherein   The high pressure inflow switching means (10) includes a valve body (102) that is movable in response to the refrigerant pressure on the first heat exchanger (3) side and the refrigerant pressure on the second heat exchanger (4) side. The high-pressure side differential pressure switching valve (10) that opens the flow path on the higher refrigerant pressure side and closes the flow path on the lower refrigerant pressure side by any high refrigerant pressure is used, and the four-way valve (2 4) The refrigeration cycle apparatus according to any one of claims 1 to 3, wherein the high-pressure refrigerant always flows into the high-pressure inflow portion (5a) even when switching is performed.   The ejector (5) is constructed by integrating the low pressure side differential pressure switching valve (9) and / or the high pressure side differential pressure switching valve (10) or both differential pressure switching valves (9, 10). The refrigeration cycle apparatus according to any one of claims 1 to 3 and 5 to 7.

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