JP4400533B2 - Ejector refrigeration cycle - Google Patents

Description

  The present invention relates to an ejector-type refrigeration cycle including a plurality of heat exchangers that exchange heat between refrigerant and air blown into an air-conditioning target space, and is suitable for, for example, a vehicle air conditioner.

  In Japanese Patent Application No. 2005-37645, the present applicant has mounted two evaporators in an ejector-type refrigeration cycle that cools a common space to be cooled by combining an ejector downstream-side evaporator and an ejector suction-side evaporator. Proposals were made to improve the performance and improve the cooling performance with two evaporators.

  However, the above Japanese Patent Application No. 2005-37645 application does not disclose any specific configuration for performing dehumidifying heating or heating.

  In view of the above points, an object of the present invention is to enable dehumidification heating without using a hot water heat source in an ejector refrigeration cycle. Another object of the present invention is to enable heating without using a hot water heat source in an ejector refrigeration cycle.

  The present invention includes a first heat exchanger (17) connected to the downstream side of the ejector (16), a second heat exchanger (23) connected to the refrigerant suction port (16b) of the ejector (16), The first branch passage (19) for guiding the refrigerant on the downstream side of the radiator (13) to the second heat exchanger (23) and the high-pressure refrigerant discharged from the compressors (11, 12, 51) are combined with the radiator (13 ) And a path setting means (20, 27, 41, 42, 52, S102, S105) for switching and setting a plurality of refrigerant flow paths, and a second branch path (26) that leads to the second heat exchanger (23). , S203, S206, S210), and the path setting means performs the first heat exchange of the high-pressure refrigerant discharged from the compressor (11, 12, 51) via the radiator (13) and the ejector (16). To the radiator (17) and the radiator (13) and The first refrigerant flow path guided to the second heat exchanger (23) through the one branch passage (19) and the high-pressure refrigerant discharged from the compressor (11, 12, 51) are connected to the radiator (13) and The second refrigerant flow path that is led to the first heat exchanger (17) via the ejector (16) and led to the second heat exchanger (23) via the second branch passage (26) is switched and set. This is a first feature.

  According to this, when the first refrigerant flow path is set, both of the two heat exchangers function as an evaporator for cooling, and when the second refrigerant flow path is set, the first heat exchange is performed. The dehumidifying heating is performed by the function of the evaporator as the evaporator and the function of the second heat exchanger as the radiator. That is, dehumidifying heating can be performed without using a hot water heat source in the ejector refrigeration cycle.

  In the present invention, the route setting means (20, 41, 42, 52, S203, S206, S210) is configured such that all the high-pressure refrigerant discharged from the compressor (11, 12, 51) is supplied to the second branch passage (26). A second feature is that the third refrigerant flow path guided to the second heat exchanger (23) via the second can be set.

  According to this, when the 3rd refrigerant | coolant flow path is set, two heat exchangers function as a heat radiator, and both are heated. That is, heating can be performed in the ejector refrigeration cycle without using a hot water heat source.

  The present invention includes a plurality of compressors (11, 12), and when the second refrigerant flow path is set, the high-pressure refrigerant discharged from some of the compressors (11) is discharged from the radiator (13) and the ejector. The high-pressure refrigerant that is guided to the first heat exchanger (17) through (16) and discharged from the other compressor (12) passes through the second branch passage (26) to the second heat exchanger (23 ) Is a third feature.

  According to this, at the time of dehumidifying heating, the cooling capacity can be controlled by some compressors, and the heating capacity can be controlled by other compressors. That is, since the cooling capacity and the heating capacity can be controlled independently, the dehumidifying capacity control and the temperature control of the blown air during the dehumidifying heating can be easily and accurately performed.

  In the present invention, the first heat exchanger (17) and the second heat exchanger (23) are arranged in series along the flow of air blown into the air-conditioning target space, and the first heat exchanger (17) is provided. The fourth feature is that the second heat exchanger (23) is disposed upstream of the air flow.

  According to this, during cooling operation, the refrigerant evaporation temperature of the second heat exchanger is lower than the refrigerant evaporation temperature of the first heat exchanger, and the first heat exchanger having a high refrigerant evaporation temperature. Is located on the upstream side of the air flow and the second heat exchanger having a low refrigerant evaporation temperature is located on the downstream side of the air flow, so that the temperature of the air to be cooled gradually increases from the upstream side to the downstream side in the air flow direction. Even if the temperature decreases, the temperature difference between the refrigerant evaporation temperature and the air temperature can be secured in both the first and second heat exchangers. Thereby, a cooling effect improves with the combination of two heat exchangers.

  Further, the temperature of the refrigerant during the heating operation is higher on the second heat exchanger side on the downstream side of the air flow than the first heat exchanger, so the air flow and the refrigerant flow are in a counterflow relationship, and each heat exchange The temperature difference between the refrigerant and the air can be ensured in the cooler to increase the heat exchange efficiency.

  In addition, the code | symbol in the bracket | parenthesis of each means described in a claim and this column shows the correspondence with the specific means as described in embodiment mentioned later.

(First embodiment)
A first embodiment of the present invention will be described. FIG. 1 is a configuration diagram of an ejector refrigeration cycle according to a first embodiment of the present invention. In the present embodiment, the ejector refrigeration cycle 10 is applied to a vehicle air conditioner. In the ejector refrigeration cycle 10 of the present embodiment, a first compressor 11 and a second compressor 12 for sucking, compressing, and discharging refrigerant are arranged in parallel to the refrigerant flow. Each of the compressors 11 and 12 has an electric motor, and the refrigerant discharge capacity of each of the compressors 11 and 12 can be adjusted by adjusting the rotation speed of the electric motor.

  The refrigerant discharge sides of both the compressors 11 and 12 are connected to the radiator 13 after joining at the junction Z. The radiator 13 is a heat exchanger having a well-known configuration having a heat exchange core part and a tank part, and the vehicle exterior air blown by the high-pressure refrigerant discharged from the compressors 11 and 12 and the first electric blower 14 (that is, The high-pressure refrigerant is cooled by exchanging heat with the outside air.

In the present embodiment, a normal chlorofluorocarbon refrigerant is used as the refrigerant of the ejector refrigeration cycle 10. In this case, since the high pressure pressure is a subcritical cycle that does not exceed the critical pressure, the radiator 13 acts as a condenser that condenses the refrigerant. Note that a refrigerant having a high pressure exceeding the critical pressure, such as carbon dioxide (CO ₂ ), may be used as the refrigerant. In this case, the ejector refrigeration cycle 10 becomes a supercritical cycle, so that the refrigerant is in a supercritical state. It just dissipates heat and does not condense.

  A mechanical expansion valve 15 is connected to the downstream side of the refrigerant flow with respect to the radiator 13 as pressure reducing means for adjusting the refrigerant flow rate to the first heat exchanger 17 (details will be described later). The mechanical expansion valve 15 includes a temperature sensitive cylinder 15 a disposed on the outlet side of the first heat exchanger 17. A gas is sealed in the temperature sensing cylinder 15a, and the gas has a pressure corresponding to the temperature of the outlet side refrigerant of the first heat exchanger 17. Then, the mechanical expansion valve 15 displaces a valve body (not shown) according to the gas pressure of the temperature sensing cylinder 15a, thereby adjusting the flow rate of the refrigerant passing through the mechanical expansion valve 15 and adjusting the first heat. Control is performed so that the degree of superheat of the outlet side refrigerant of the exchanger 17 approaches a predetermined value.

  An ejector 16 is connected to the downstream side of the refrigerant flow with respect to the mechanical expansion valve 15. The ejector 16 is a pressure reducing means for reducing the pressure of the refrigerant, and is also a refrigerant circulating means for circulating the refrigerant by a suction action (winding action) of the refrigerant flow ejected at a high speed.

  The ejector 16 is arranged in the same space as the nozzle portion 16a for reducing the passage area of the high-pressure refrigerant flowing from the radiator 13 to be isentropically decompressed and expanded, and the refrigerant outlet of the nozzle portion 16a. A refrigerant suction port 16b for sucking a gas-phase refrigerant from a second heat exchanger 23 to be described later is provided.

  Furthermore, the ejector 16 is provided with a mixing portion 16c that mixes the high-speed refrigerant flow from the nozzle portion 16a and the suction refrigerant from the refrigerant suction port 16b at the downstream portion of the refrigerant flow of the nozzle portion 16a and the refrigerant suction port 16b. It has been. And the diffuser part 16d which makes a pressure | voltage rise part is arrange | positioned in the refrigerant | coolant flow downstream of the mixing part 16c. The diffuser portion 16d is formed in a shape that gradually increases the refrigerant passage area, and acts to decelerate the refrigerant flow to increase the refrigerant pressure, that is, to convert the velocity energy of the refrigerant into pressure energy.

  A first heat exchanger 17 is connected to the downstream side of the refrigerant flow of the diffuser portion 16 d of the ejector 16. An accumulator 18 that separates the liquid-phase refrigerant and the gas-phase refrigerant is connected to the downstream side of the refrigerant flow of the first heat exchanger 17. The accumulator 18 is connected to the suction side of the compressors 11 and 12, and the gas phase refrigerant separated by the accumulator 18 is sucked into the compressors 11 and 12.

  On the other hand, a first branch passage 19 is branched from between the radiator 13 and the ejector 16, more specifically from between the mechanical expansion valve 15 and the nozzle portion 16 a of the ejector 16. The downstream end of the flow is connected to the refrigerant suction port 16 b of the ejector 16. The high-pressure refrigerant that has passed through the radiator 13 is guided to the second heat exchanger 23 by bypassing the ejector 16 by the first branch passage 19. Y indicates a branch point of the first branch passage 19.

  In the first branch passage 19, a first on-off valve 20, a first check valve 21, an electric expansion valve 22, and a second heat exchanger 23 are sequentially arranged along the refrigerant flow. The first on-off valve 20 opens and closes the first branch passage 19 and specifically comprises an electromagnetic valve. The electric expansion valve 22 is a pressure reducing means for adjusting the flow rate of the refrigerant to the second heat exchanger 23. Specifically, the valve opening degree can be adjusted by an electric actuator.

  The first heat exchanger 17 and the second heat exchanger 23 are heat exchangers having a known configuration having a heat exchange core part and a tank part, and are housed in one case. Then, air is blown into the air passage formed in the case by the suction-type second electric blower 24, and heat exchange is performed between the blown air and the refrigerant. The heat-exchanged air is blown out into the passenger compartment that is an air-conditioning target space. Here, the first heat exchanger 17 and the second heat exchanger 23 are arranged in series along the air flow, and the first heat exchanger 17 connected to the main flow path on the downstream side of the ejector 16 includes: The second heat exchanger 23 connected to the refrigerant suction port 16b of the ejector 16 is disposed upstream of the air flow. In addition, a temperature sensor 25 that detects the temperature of the air blown into the passenger compartment is disposed downstream of the second heat exchanger 23 in the air flow.

  Further, the second branch passage 26 is branched from between the second compressor 12 and the junction Z, and the downstream end of the refrigerant flow downstream of the second branch passage 26 is a first check valve in the first branch passage 19. 21 and the electric expansion valve 22. The high-pressure refrigerant discharged from the second compressor 12 is guided to the second heat exchanger 23 by bypassing the radiator 13 by the second branch passage 26.

  An electric switching valve 27 that switches the flow direction of the refrigerant discharged from the second compressor 12 is disposed at a branch portion of the second branch passage 26. A second check valve 28 is disposed between the switching valve 27 and the junction Z, and a third check valve 29 is disposed in the second branch passage 26. The first on-off valve 20 and the switching valve 27 form part of the route setting means of the present invention.

  The ECU 30 includes a known microcomputer including a CPU, a ROM, a RAM, and the like (not shown), performs predetermined arithmetic processing according to a program stored in the microcomputer, and performs the first compressor 11, the second compressor 12, and the first compressor. The operation of the electric blower 14, the first on-off valve 20, the electric expansion valve 22, the second electric blower 24, and the switching valve 27 is controlled.

  The ECU 30 receives a signal from the temperature sensor 25 described above and a signal from the sensor / switch group 31. The sensor / switch group 31 includes an internal air temperature sensor that detects the vehicle interior temperature (that is, the internal air temperature), an external air temperature sensor that detects the external air temperature, a humidity sensor that detects the vehicle interior humidity, and a passenger command to execute / stop the cooling operation. And a dehumidifying switch that instructs the occupant to execute / stop the dehumidifying and heating operation, a temperature setting switch that allows the occupant to set a desired vehicle interior temperature (hereinafter referred to as a set temperature), and the like.

  Next, the operation of the first embodiment will be described. FIG. 2 is a block diagram showing a cooling mode state, and FIG. 3 is a block diagram showing a dehumidifying heating mode state.

  In the refrigeration cycle of the present embodiment, the refrigerant flow path is switched by the first on-off valve 20 and the switching valve 27, whereby the cooling mode and the dehumidifying heating mode are set.

  (Cooling mode) First, the operation in the cooling mode will be described. When performing the cooling operation, the first on-off valve 20 opens the first branch passage 19 and the switching valve 27 operates to a position where the second compressor 12 and the junction Z are in communication. Thus, in the cooling mode, the refrigerant flows in the direction indicated by the arrow in the portion indicated by the thick line in FIG. 2, and the refrigerant flow path in the cooling mode is set. This refrigerant flow path in the cooling mode corresponds to the first refrigerant flow path of the present invention.

  When both compressors 11 and 12 are driven, the high-temperature and high-pressure refrigerant compressed and discharged by the compressors 11 and 12 flows into the radiator 13. In the radiator 13, the high-temperature refrigerant is cooled and condensed by the outside air. The high-pressure liquid-phase refrigerant that has flowed out of the radiator 13 is divided into a refrigerant flow toward the ejector 16 and a refrigerant flow toward the first branch passage 19 at the branch point Y.

  The refrigerant flow flowing into the ejector 16 is decompressed and expanded by the nozzle portion 16a. Accordingly, the pressure energy of the refrigerant is converted into velocity energy at the nozzle portion 16a, and the refrigerant is ejected at a high velocity from the outlet of the nozzle portion 16a. Due to the refrigerant pressure drop at this time, the gas-phase refrigerant after passing through the second heat exchanger 23 is sucked from the refrigerant suction port 16b.

  The refrigerant ejected from the nozzle portion 16a and the refrigerant sucked into the refrigerant suction port 16b are mixed in the mixing portion 16c on the downstream side of the nozzle portion 16a and flow into the diffuser portion 16d. In the diffuser portion 16d, the passage area is enlarged, so that the velocity energy of the refrigerant is converted into pressure energy, so that the pressure of the refrigerant rises.

  Then, the refrigerant that has flowed out of the diffuser portion 16 d of the ejector 16 flows into the first heat exchanger 17. In the first heat exchanger 17, the low-temperature low-pressure refrigerant absorbs heat from the blown air and evaporates. The vapor phase refrigerant after evaporation is sucked into the compressors 11 and 12 and compressed again.

  On the other hand, the refrigerant flow flowing into the first branch passage 19 is decompressed by the electric expansion valve 22 to become a low-pressure refrigerant, and this low-pressure refrigerant flows into the second heat exchanger 23. In the second heat exchanger 23, the refrigerant absorbs heat from the blown air after passing through the first heat exchanger 17 and evaporates. The vapor phase refrigerant after evaporation is sucked into the ejector 16 from the refrigerant suction port 16b.

  Next, control in the cooling mode will be described. FIG. 4 is a flowchart showing a program executed by the ECU 30. When a cooling operation execution command is issued by the cooling switch (Yes in Step S101), the refrigerant flow path in the cooling mode is changed in Step S102. Set. Specifically, the first on-off valve 20 is controlled to open the first branch passage 19, and the switching valve 27 is controlled to a position at which the second compressor 12 and the junction Z are communicated. Step S102 forms part of the route setting means of the present invention.

  Next, in step S103, the first electric blower 14 is operated, and the first compressor 11, the second compressor 12, the electric expansion valve 22, and the second electric blower 24 are used to adjust the cooling capacity. Control the operation of Specifically, the refrigerant discharge capacity of each of the compressors 11 and 12, the valve opening degree of the electric expansion valve 22, so that the inside air temperature detected by the inside air temperature sensor approaches the set temperature set by the temperature setting switch, And the ventilation volume of the 2nd electric blower 24 is adjusted.

  As described above, in the cooling mode, since both the heat exchangers 17 and 23 function as an evaporator and simultaneously exhibit a cooling action, the cold air cooled by both the heat exchangers 17 and 23 is blown out into the vehicle interior. To cool the passenger compartment.

  At that time, the refrigerant evaporating pressure of the first heat exchanger 17 is the pressure after being increased by the diffuser portion 16d, while the outlet side of the second heat exchanger 23 is connected to the refrigerant suction port 16b of the ejector 16. Therefore, the lowest pressure immediately after the pressure reduction at the nozzle portion 16 a can be applied to the second heat exchanger 23.

  Accordingly, the refrigerant evaporation pressure (refrigerant evaporation temperature) of the second heat exchanger 23 can be made lower than the refrigerant evaporation pressure (refrigerant evaporation temperature) of the first heat exchanger 17. And since the 1st heat exchanger 17 with a high refrigerant | coolant evaporation temperature is arrange | positioned in the upstream with respect to the flow direction of blowing air, and the 2nd heat exchanger 23 with a low refrigerant | coolant evaporation temperature is arrange | positioned in the downstream, Both the temperature difference between the refrigerant evaporation temperature and the blown air in the first heat exchanger 17 and the temperature difference between the refrigerant evaporation temperature and the blown air in the second heat exchanger 23 can be ensured. For this reason, both the cooling performances of the heat exchangers 17 and 23 can be effectively exhibited. Therefore, the cooling performance for the common vehicle compartment can be effectively improved by the combination of the heat exchangers 17 and 23.

  Moreover, the suction pressure of both the compressors 11 and 12 can be raised by the pressure | voltage rise effect | action in the diffuser part 16d, and the drive power of both the compressors 11 and 12 can be reduced.

  (Dehumidifying Heating Mode) Next, the operation in the dehumidifying heating mode will be described. When the dehumidifying and heating operation is performed, the first on-off valve 20 closes the first branch passage 19 and the switching valve 27 operates to a position where the second compressor 12 and the second branch passage 26 are communicated with each other. Thereby, at the time of dehumidification heating mode, a refrigerant | coolant will flow through the site | part shown by the thick line in FIG. 3 in the direction of the arrow, and the refrigerant | coolant flow path | route of dehumidification heating mode is set. This refrigerant flow path in the dehumidifying and heating mode corresponds to the second refrigerant flow path of the present invention.

  When the compressors 11 and 12 are driven, the high-temperature and high-pressure refrigerant compressed and discharged by the first compressor 11 flows into the radiator 13. In the radiator 13, the high-temperature refrigerant is cooled and condensed by the outside air. All the high-pressure liquid-phase refrigerant that has flowed out of the radiator 13 flows into the ejector 16.

  The refrigerant that has flowed into the ejector 16 is decompressed and expanded by the nozzle portion 16a, and is ejected from the ejection port of the nozzle portion 16a at a high speed. The refrigerant ejected from the nozzle portion 16a and the refrigerant sucked into the refrigerant suction port 16b are mixed in the mixing portion 16c on the downstream side of the nozzle portion 16a and flow into the diffuser portion 16d. Then, the refrigerant that has flowed out of the diffuser portion 16 d flows into the first heat exchanger 17. In the first heat exchanger 17, the low-temperature low-pressure refrigerant absorbs heat from the blown air and evaporates. The vapor phase refrigerant after evaporation is sucked into the compressors 11 and 12 and compressed again.

  On the other hand, the high-temperature and high-pressure refrigerant compressed and discharged by the second compressor 12 flows into the second heat exchanger 23 through the second branch passage 26, the electric expansion valve 22 and the first branch passage 19. At this time, after performing a predetermined pressure reduction by the electric expansion valve 22, the refrigerant flows into the second heat exchanger 23 in a hot gas state. Therefore, in the second heat exchanger 23, the refrigerant releases heat to the blown air after passing through the first heat exchanger 17 to heat the blown air. The heat-dissipated gas-phase refrigerant is sucked into the ejector 16 from the refrigerant suction port 16b.

  Next, the control at the time of dehumidification heating mode is demonstrated. In FIG. 4, when a cooling operation stop command is issued by the cooling switch (No in step S101) and a dehumidifying heating operation execution command is issued by the dehumidifying switch (Yes determination in step S104), In step S105, a refrigerant flow path in the dehumidifying and heating mode is set. Specifically, the first on-off valve 20 is controlled to close the first branch passage 19, and the switching valve 27 is controlled to a position where the second compressor 12 and the second branch passage 26 are communicated. Step S105 forms part of the route setting means of the present invention.

  Subsequently, it progresses to step S106 and the 1st electric blower 14 and the 2nd electric blower 24 are operated.

  Next, the process proceeds to step S107, where the required dehumidifying capacity is calculated based on the humidity inside the vehicle detected by the humidity sensor and the target humidity stored in advance in the ROM of the ECU 30, and the first dehumidifying capacity is obtained so that the required dehumidifying capacity is obtained. The refrigerant discharge capacity of the compressor 11 is controlled.

  Next, the process proceeds to step S108, and the refrigerant discharge of the second compressor 12 is performed so that the temperature of the blown air detected by the temperature sensor 25 becomes a target temperature determined based on the outside air temperature detected by the outside air temperature sensor. Control capacity and control heating capacity. A map that defines the relationship between the target temperature and the outside air temperature is stored in the ROM of the ECU 30, and the target temperature is obtained from the map. The target temperature may be obtained by other methods, for example, based on the difference between the internal temperature and the set temperature.

  As described above, in the dehumidifying heating mode, the first heat exchanger 17 functions as an evaporator and the second heat exchanger 23 functions as a radiator, so that dehumidifying heating can be performed. That is, dehumidifying heating can be performed without using a hot water heat source in the ejector refrigeration cycle.

  Thus, since a hot water heat source is unnecessary, it is not necessary to provide a hot water heating heat exchanger or hot water piping unlike a conventional vehicle air conditioner. In particular, in a large vehicle such as a bus, since the hot water pipe connecting the heat exchanger for heating and the hot water heat source (that is, the water-cooled internal combustion engine) tends to be long, the ejector refrigeration cycle of the present embodiment is particularly Suitable for large vehicles such as buses.

  Moreover, the suction pressure of both the compressors 11 and 12 can be raised by the pressure | voltage rise effect | action in the diffuser part 16d, and the drive power of both the compressors 11 and 12 can be reduced.

  Further, at the time of dehumidifying heating, the cooling capacity can be controlled by the first compressor 11, and the heating capacity can be controlled by the second compressor 12. That is, since the cooling capacity and the heating capacity can be controlled independently, the dehumidifying capacity control and the temperature control of the blown air during the dehumidifying heating can be easily and accurately performed.

(Second Embodiment)
A second embodiment of the present invention will be described. FIG. 5 is a block diagram showing the cooling mode state of the ejector refrigeration cycle according to the second embodiment of the present invention, FIG. 6 is a block diagram showing the dehumidifying heating mode state, and FIG. 7 is a block diagram showing the heating mode state. The same or equivalent parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In the present embodiment, a second on-off valve 41 and a third on-off valve 42 are provided instead of the switching valve 27 in the first embodiment. The second on-off valve 41 opens and closes between the second compressor 12 and the junction Z, and the third on-off valve 42 opens and closes the second branch passage 26. Specifically, the second on-off valve 41 and the third on-off valve 42 are constituted by electromagnetic valves.

  Further, in the first embodiment, the ejector 16 having a constant refrigerant flow area of the nozzle 16a is used, but in this embodiment, the variable ejector 16 that adjusts the refrigerant flow area of the nozzle 16a by an electric actuator is used. Yes. Moreover, the ejector 16 of this embodiment can fully close the nozzle 16a. The ejector 16 that can fully close the nozzle 16a and the first to third on-off valves 20, 41, and 42 form a part of the path setting means of the present invention.

  In the present embodiment, the mechanical expansion valve 15 and the second check valve 28 in the first embodiment are eliminated. Further, the sensor / switch group 31 of the present embodiment includes an air conditioner switch that instructs the occupant to execute and stop the cooling and heating operation instead of the cooling switch in the first embodiment.

  Next, the operation of the second embodiment will be described. As described below, in the refrigeration cycle of the present embodiment, a cooling mode, a dehumidifying heating mode, and a heating mode are set.

  (Cooling mode) First, the operation in the cooling mode will be described. When performing the cooling operation, the first on-off valve 20 opens the first branch passage 19, the second on-off valve 41 communicates the second compressor 12 and the junction Z, and the third on-off valve 42 The branch passage 26 is closed. Thus, in the cooling mode, the refrigerant flows in the direction indicated by the arrow in the part indicated by the thick line in FIG. 5, and the refrigerant flow path in the cooling mode is set. This refrigerant flow path in the cooling mode corresponds to the first refrigerant flow path of the present invention.

  When both compressors 11 and 12 are driven, the high-temperature and high-pressure refrigerant compressed and discharged by the compressors 11 and 12 flows into the radiator 13. In the radiator 13, the high-temperature refrigerant is cooled and condensed by the outside air. The high-pressure liquid-phase refrigerant that has flowed out of the radiator 13 is divided into a refrigerant flow toward the ejector 16 and a refrigerant flow toward the first branch passage 19 at the branch point Y.

  The refrigerant flowing into the ejector 16 is decompressed by the nozzle portion 16a and flows into the first heat exchanger 17, where the low-temperature low-pressure refrigerant absorbs heat from the blown air and evaporates.

  On the other hand, the refrigerant flowing into the first branch passage 19 is decompressed by the electric expansion valve 22 and flows into the second heat exchanger 23, and the second heat exchanger 23 blows air after passing through the first heat exchanger 17. The refrigerant absorbs heat from the air and evaporates.

  Next, control in the cooling mode will be described. FIG. 8 is a flowchart showing a program executed by the ECU 30, in which a cooling and heating operation execution command is issued by the air conditioner switch (Yes in step S <b> 201), and the inside air temperature detected by the inside air temperature sensor is the temperature. If the temperature is equal to or higher than the set temperature set by the setting switch (Yes in step S202), the refrigerant flow path in the cooling mode is set in step S203. Specifically, the first on-off valve 20 is controlled to open the first branch passage 19, the second on-off valve 41 is controlled to communicate the second compressor 12 and the junction point Z, and the third on-off valve The valve 42 is controlled to close the second branch passage 26. Note that step S203 forms part of the route setting means of the present invention.

  Next, the process proceeds to step S204 to operate the first electric blower 14 and to adjust the cooling capacity, the first compressor 11, the second compressor 12, the ejector 16, the electric expansion valve 22, and the second The operation of the electric blower 24 is controlled. Specifically, the refrigerant discharge capacity of each of the compressors 11 and 12 and the refrigerant flow area of the nozzle 16a of the ejector 16 so that the inside air temperature detected by the inside air temperature sensor approaches the set temperature set by the temperature setting switch. The valve opening degree of the electric expansion valve 22 and the blast volume of the second electric blower 24 are adjusted.

  As described above, in the cooling mode, since both the heat exchangers 17 and 23 function as an evaporator and simultaneously exhibit a cooling action, the cold air cooled by both the heat exchangers 17 and 23 is blown out into the vehicle interior. To cool the passenger compartment.

  (Dehumidifying Heating Mode) Next, the operation in the dehumidifying heating mode will be described. When performing the dehumidifying and heating operation, the first on-off valve 20 closes the first branch passage 19, the second on-off valve 41 shuts off between the second compressor 12 and the junction Z, and the third on-off valve 42. Opens the second branch passage 26. Thereby, at the time of dehumidification heating mode, a refrigerant | coolant will flow through the site | part shown by the thick line in FIG. 6 in the direction of the arrow, and the refrigerant | coolant flow path | route of dehumidification heating mode is set. This refrigerant flow path in the dehumidifying and heating mode corresponds to the second refrigerant flow path of the present invention.

  When the compressors 11 and 12 are driven, the high-temperature and high-pressure refrigerant compressed and discharged by the first compressor 11 flows into the radiator 13. In the radiator 13, the high-temperature refrigerant is cooled and condensed by the outside air. All the high-pressure liquid-phase refrigerant that has flowed out of the radiator 13 flows into the ejector 16. The refrigerant flowing into the ejector 16 is decompressed by the nozzle portion 16a and flows into the first heat exchanger 17, where the low-temperature low-pressure refrigerant absorbs heat from the blown air and evaporates.

  On the other hand, the high-temperature and high-pressure refrigerant compressed and discharged by the second compressor 12 flows into the second heat exchanger 23 through the second branch passage 26, the electric expansion valve 22 and the first branch passage 19. At this time, after performing a predetermined pressure reduction by the electric expansion valve 22, the refrigerant flows into the second heat exchanger 23 in a hot gas state. Therefore, in the second heat exchanger 23, the refrigerant releases heat to the blown air after passing through the first heat exchanger 17 to heat the blown air. The heat-dissipated gas-phase refrigerant is sucked into the ejector 16 from the refrigerant suction port 16b.

  Next, the control at the time of dehumidification heating mode is demonstrated. In FIG. 8, when the air conditioning switch issues a stop command for cooling and heating operation (No in step S201) and the dehumidification switch issues an execution command for dehumidifying and heating operation (Yes in step S205) ) In step S206, the refrigerant flow path in the dehumidifying heating mode is set. Specifically, the first on-off valve 20 is controlled to close the first branch passage 19, the second on-off valve 41 is controlled to shut off the second compressor 12 and the junction Z, The 3 on-off valve 42 is controlled to open the second branch passage 26. Note that step S206 forms part of the route setting means of the present invention.

  Subsequently, it progresses to step S207 and the 1st electric blower 14 and the 2nd electric blower 24 are operated.

  Next, the process proceeds to step S208, where the required dehumidifying capacity is calculated based on the vehicle interior humidity detected by the humidity sensor and the target humidity stored in advance in the ROM of the ECU 30, and the required dehumidifying capacity is obtained. The refrigerant discharge capacity of one compressor 11 and the refrigerant flow area of the nozzle 16a of the ejector 16 are controlled.

  Next, the process proceeds to step S209, and the refrigerant discharge of the second compressor 12 is performed so that the temperature of the blown air detected by the temperature sensor 25 becomes a target temperature determined based on the outside air temperature detected by the outside air temperature sensor. Control capacity and control heating capacity.

  As described above, in the dehumidifying heating mode, the first heat exchanger 17 functions as an evaporator and the second heat exchanger 23 functions as a radiator, so that dehumidifying heating can be performed. That is, dehumidifying heating can be performed without using a hot water heat source in the ejector refrigeration cycle.

  (Heating mode) Next, the operation in the heating mode will be described. When performing the heating operation, the first on-off valve 20 closes the first branch passage 19, the second on-off valve 41 communicates the second compressor 12 and the junction Z, and the third on-off valve 42 The branch passage 26 is opened, and the ejector 16 fully closes the nozzle 16a. Thereby, in the heating mode, the refrigerant flows in the direction of the arrow through the portion indicated by the thick line in FIG. 7, and the refrigerant flow path in the heating mode is set. This refrigerant flow path in the heating mode corresponds to the third refrigerant flow path of the present invention.

  When both the compressors 11 and 12 are driven, all the refrigerant in the high temperature and high pressure state compressed and discharged by the two compressors 11 and 12 is discharged from the second branch passage 26, the electric expansion valve 22 and the first branch passage 19. It flows into the 2nd heat exchanger 23 via. At this time, after performing a predetermined pressure reduction by the electric expansion valve 22, the refrigerant flows into the second heat exchanger 23 in a hot gas state. Accordingly, in the second heat exchanger 23, the high-temperature refrigerant radiates heat to the blown air and heats the blown air. The refrigerant that has passed through the second heat exchanger 23 passes through the ejector 16 and flows into the first heat exchanger 17 while maintaining a high temperature state. Accordingly, in the first heat exchanger 17, the high-temperature refrigerant dissipates heat to the blown air and heats the blown air.

  Next, control in the heating mode will be described. In FIG. 8, execution commands for cooling and heating operations are issued by the air conditioner switch (Yes in step S201), and the inside air temperature detected by the inside air temperature sensor is less than the set temperature set by the temperature setting switch. In this case (No at Step S202), the refrigerant flow path in the heating mode is set at Step S210. Specifically, the first on-off valve 20 is controlled to close the first branch passage 19, the second on-off valve 41 is controlled to communicate the second compressor 12 and the junction Z, and the third on-off valve is controlled. The valve 42 is controlled to open the second branch passage 26, and the nozzle 16a of the ejector 16 is controlled to be fully closed. Step S210 forms part of the route setting means of the present invention.

  Subsequently, it progresses to step S211 and operates the 1st electric blower 14 and controls the action | operation of the 1st compressor 11, the 2nd compressor 12, and the 2nd electric blower 24 in order to adjust a heating capability. Specifically, the refrigerant discharge capacity of each of the compressors 11 and 12 and the air flow rate of the second electric blower 24 are adjusted so that the inside air temperature detected by the inside air temperature sensor approaches the set temperature set by the temperature setting switch. To do.

  As described above, in the heating mode, since both the heat exchangers 17 and 23 function as a radiator and simultaneously exert a heating action, the warm air heated by both the heat exchangers 17 and 23 is put into the vehicle interior. The vehicle interior can be heated by blowing it out. That is, heating can be performed in the ejector refrigeration cycle without using a hot water heat source.

  In addition, since the temperature of the refrigerant during the heating operation is higher on the second heat exchanger 23 side on the downstream side of the air flow than the first heat exchanger 17, the air flow and the refrigerant flow are in a counterflow relationship, In the heat exchangers 17 and 23, the temperature difference between the refrigerant and air can be ensured to increase the heat exchange efficiency.

(Third embodiment)
A third embodiment of the present invention will be described. FIG. 9 is a block diagram showing a cooling mode state of an ejector refrigeration cycle according to a third embodiment of the present invention, FIG. 10 is a block diagram showing a dehumidifying heating mode state, and FIG. 11 is a block diagram showing a heating mode state. The same or equivalent parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In the first embodiment, two compressors 11 and 12 are used, but in the present embodiment, one compressor 51 is used.

  Further, in this embodiment, a flow rate adjustment valve 52 that distributes the refrigerant discharged from the compressor 51 to the radiator 13 side and the second branch passage 26 side is used instead of the switching valve 27 in the first embodiment. . The valve position of the flow rate adjusting valve 52 is adjusted by an electric actuator so that the refrigerant distribution ratio can be adjusted. The first on-off valve 20 and the flow rate adjustment valve 52 form part of the path setting means of the present invention.

  In this embodiment, the accumulator 18 and the second check valve 28 in the first embodiment are eliminated. Further, the sensor / switch group 31 of the present embodiment includes an air conditioner switch that instructs the occupant to execute and stop the cooling and heating operation instead of the cooling switch in the first embodiment.

  Next, the operation of the third embodiment will be described. As described below, in the refrigeration cycle of the present embodiment, a cooling mode, a dehumidifying heating mode, and a heating mode are set.

  (Cooling mode) First, the operation in the cooling mode will be described. When the air conditioner switch issues a cooling and heating operation execution command and the internal air temperature detected by the internal air temperature sensor is equal to or higher than the set temperature set by the temperature setting switch, the cooling mode refrigerant flow path is Is set. That is, the first on-off valve 20 opens the first branch passage 19, and the flow rate adjustment valve 52 is controlled so that all the refrigerant discharged from the compressor 51 flows to the radiator 13 side. Thus, in the cooling mode, the refrigerant flows in the direction indicated by the arrow in the portion indicated by the thick line in FIG. 9, and the refrigerant flow path in the cooling mode is set. This refrigerant flow path in the cooling mode corresponds to the first refrigerant flow path of the present invention.

  When the compressor 51 is driven, the high-temperature and high-pressure refrigerant compressed and discharged by the compressor 51 flows into the radiator 13. In the radiator 13, the high-temperature refrigerant is cooled and condensed by the outside air. The high-pressure liquid-phase refrigerant that has flowed out of the radiator 13 is divided into a refrigerant flow toward the ejector 16 and a refrigerant flow toward the first branch passage 19 at the branch point Y.

  The refrigerant flowing into the ejector 16 is decompressed by the nozzle portion 16a and flows into the first heat exchanger 17, where the low-temperature low-pressure refrigerant absorbs heat from the blown air and evaporates.

  On the other hand, the refrigerant flowing into the first branch passage 19 is decompressed by the electric expansion valve 22 and flows into the second heat exchanger 23, and the second heat exchanger 23 blows air after passing through the first heat exchanger 17. The refrigerant absorbs heat from the air and evaporates.

  Note that the refrigerant discharge capacity of the compressor 51, the valve opening degree of the electric expansion valve 22, and the air flow rate of the second electric blower 24 are adjusted so that the inside air temperature approaches the set temperature set by the temperature setting switch. Adjust the cooling capacity.

  (Dehumidifying Heating Mode) Next, the operation in the dehumidifying heating mode will be described. When a command for stopping the cooling and heating operation is issued by the air conditioner switch and a command for executing the dehumidifying heating operation is issued by the dehumidifying switch, the refrigerant flow path in the dehumidifying heating mode is set. That is, the first on-off valve 20 closes the first branch passage 19 and the flow rate adjustment valve 52 is controlled so that the refrigerant discharged from the compressor 51 flows to both the radiator 13 side and the second branch passage 26 side. . Thereby, at the time of dehumidification heating mode, a refrigerant | coolant flows through the site | part shown by the thick line in FIG. 10 in the direction of the arrow, and the refrigerant | coolant flow path | route of dehumidification heating mode is set. This refrigerant flow path in the dehumidifying and heating mode corresponds to the second refrigerant flow path of the present invention.

  When the compressor 51 is driven, the refrigerant distributed to the radiator 13 among the high-temperature and high-pressure refrigerant compressed and discharged by the compressor 51 is cooled by the outside air and condensed by the radiator 13. All the high-pressure liquid-phase refrigerant that has flowed out of the radiator 13 flows into the ejector 16. The refrigerant flowing into the ejector 16 is decompressed by the nozzle portion 16a and flows into the first heat exchanger 17, where the low-temperature low-pressure refrigerant absorbs heat from the blown air and evaporates.

  On the other hand, the refrigerant distributed to the second branch passage 26 among the high-temperature and high-pressure refrigerant compressed and discharged by the compressor 51 passes through the second branch passage 26, the electric expansion valve 22, and the first branch passage 19. Into the second heat exchanger 23. At this time, after performing a predetermined pressure reduction by the electric expansion valve 22, the refrigerant flows into the second heat exchanger 23 in a hot gas state. Therefore, in the second heat exchanger 23, the refrigerant releases heat to the blown air after passing through the first heat exchanger 17 to heat the blown air. The heat-dissipated gas-phase refrigerant is sucked into the ejector 16 from the refrigerant suction port 16b.

  In addition, the refrigerant | coolant discharge capability of the compressor 11 and the refrigerant | coolant distribution amount to the radiator 13 side are controlled so that required dehumidification capability may be obtained. Further, when the temperature of the blown air is lower than the target temperature, the refrigerant discharge capacity of the compressor 11 and the refrigerant distribution amount to the second branch passage 26 side are controlled so that the temperature of the blown air rises to the target temperature. .

  As described above, in the dehumidifying heating mode, the first heat exchanger 17 functions as an evaporator and the second heat exchanger 23 functions as a radiator, so that dehumidifying heating can be performed. That is, dehumidifying heating can be performed without using a hot water heat source in the ejector refrigeration cycle.

  (Heating mode) Next, the operation in the heating mode will be described. When the air conditioner switch issues a cooling and heating operation execution command and the internal air temperature detected by the internal air temperature sensor is lower than the set temperature set by the temperature setting switch, the refrigerant flow path in the heating mode is Is set. That is, the first on-off valve 20 closes the first branch passage 19, and the flow rate adjustment valve 52 is controlled so that all the refrigerant discharged from the compressor 51 flows to the second branch passage 26 side. Thus, in the heating mode, the refrigerant flows in the direction of the arrow through the portion indicated by the thick line in FIG. 11, and the refrigerant flow path in the heating mode is set. This refrigerant flow path in the heating mode corresponds to the third refrigerant flow path of the present invention.

  When the compressor 51 is driven, all the high-temperature and high-pressure refrigerant compressed and discharged by the compressor 51 passes through the second branch passage 26, the electric expansion valve 22, and the first branch passage 19 to generate the second heat. It flows into the exchanger 23. At this time, after performing a predetermined pressure reduction by the electric expansion valve 22, the refrigerant flows into the second heat exchanger 23 in a hot gas state. Accordingly, in the second heat exchanger 23, the high-temperature refrigerant radiates heat to the blown air and heats the blown air. The refrigerant that has passed through the second heat exchanger 23 passes through the ejector 16 and flows into the first heat exchanger 17 while maintaining a high temperature state. Accordingly, in the first heat exchanger 17, the high-temperature refrigerant dissipates heat to the blown air and heats the blown air.

  It should be noted that the heating capacity is adjusted by adjusting the refrigerant discharge capacity of the compressor 51 and the blast volume of the second electric blower 24 so that the inside air temperature approaches the set temperature.

  As described above, in the heating mode, since both the heat exchangers 17 and 23 function as a radiator and simultaneously exert a heating action, the warm air heated by both the heat exchangers 17 and 23 is put into the vehicle interior. The vehicle interior can be heated by blowing it out. That is, heating can be performed in the ejector refrigeration cycle without using a hot water heat source.

(Other embodiments)
(1) In each of the above embodiments, the compressors 11, 12, and 51 may be rotationally driven by a vehicle travel engine (not shown). In this case, a variable capacity capable of adjusting the refrigerant discharge capacity by changing the discharge capacity. Either a type compressor or a fixed capacity type compressor that adjusts the refrigerant discharge capacity by changing the operating rate of the compressor operation by switching of the electromagnetic clutch may be used.

  (2) The first embodiment shown in FIG. 1 may be modified as follows. First, the mechanical expansion valve 15 may be eliminated. Further, the mechanical expansion valve 15 may be eliminated, and instead, the ejector 16 may be changed to a variable type ejector 16 in which the refrigerant flow area of the nozzle 16a is adjusted by an electric actuator. Further, the electric expansion valve 22 may be changed to a fixed throttle having a constant refrigerant flow area. Further, instead of the switching valve 27, a second on-off valve 41 and a third on-off valve 42 may be used as in the second embodiment. Further, the accumulator 18 may be eliminated.

  (3) The second embodiment shown in FIG. 5 may be modified as follows. First, the ejector 16 is changed to the ejector 16 having a constant refrigerant flow area of the nozzle 16a, and a control device such as an electronic expansion valve capable of stopping the refrigerant flow to the ejector 16 is installed on the upstream side of the ejector 16. May be. Further, the accumulator 18 may be eliminated.

  (4) The third embodiment shown in FIG. 9 may be modified as follows. First, the mechanical expansion valve 15 may be eliminated. Further, the mechanical expansion valve 15 may be eliminated, and instead, the ejector 16 may be changed to a variable type ejector 16 in which the refrigerant flow area of the nozzle 16a is adjusted by an electric actuator.

(5) Moreover, although the above embodiment demonstrated the refrigeration cycle for vehicles, it cannot be overemphasized that this invention can be similarly applied not only to vehicles but to refrigeration cycles for stationary use. In the above embodiment, the type of the refrigerant was not specified, but the refrigerant may be any one of a supercritical cycle and a subcritical cycle of vapor compression type such as CFC-based, HC-based alternative CFC, carbon dioxide (CO ₂ ). It may be applicable.

  Here, chlorofluorocarbon is a general term for organic compounds composed of carbon, fluorine, chlorine, and hydrogen, and is widely used as a refrigerant. Fluorocarbon refrigerants include HCFC (hydro-chloro-fluoro-carbon) refrigerants, HFC (hydro-fluoro-carbon) refrigerants, etc., and these are refrigerants called substitute chlorofluorocarbons because they do not destroy the ozone layer. is there.

  The HC (hydrocarbon) refrigerant is a refrigerant substance that contains hydrogen and carbon and exists in nature. Examples of the HC refrigerant include R600a (isobutane) and R290 (propane).

1 is a configuration diagram of an ejector refrigeration cycle according to a first embodiment of the present invention. It is a block diagram which shows the air_conditioning | cooling mode state of the ejector-type refrigerating cycle which concerns on 1st Embodiment. It is a block diagram which shows the dehumidification heating mode state of the ejector-type refrigerating cycle which concerns on 1st Embodiment. It is a flowchart which shows the program run by ECU30 of FIG. It is a block diagram which shows the air_conditioning | cooling mode state of the ejector-type refrigerating cycle which concerns on 2nd Embodiment of this invention. It is a block diagram which shows the dehumidification heating mode state of the ejector-type refrigerating cycle which concerns on 2nd Embodiment. It is a block diagram which shows the heating mode state of the ejector-type refrigerating cycle which concerns on 2nd Embodiment. It is a flowchart which shows the program performed with ECU30 of FIG. It is a block diagram which shows the air_conditioning | cooling mode state of the ejector-type refrigerating cycle which concerns on 3rd Embodiment of this invention. It is a block diagram which shows the dehumidification heating mode state of the ejector-type refrigeration cycle which concerns on 3rd Embodiment. It is a block diagram which shows the heating mode state of the ejector-type refrigerating cycle which concerns on 3rd Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11, 12, 51 ... Compressor, 13 ... Radiator, 16 ... Ejector, 16a ... Nozzle part, 16b ... Refrigerant suction port, 16c ... Mixing part, 16d ... Diffuser part, 17 ... First heat exchanger, 19 ... First 1 branch passage, 20 ... first on-off valve (path setting means), 23 ... second heat exchanger, 26 ... second branch passage, 27 ... switching valve (path setting means), 41 ... second on-off valve (path setting) Means), 42... Third on-off valve (path setting means), 52. Flow rate adjusting valve (path setting means).

Claims (9)

A compressor (11, 12, 51) for sucking and compressing refrigerant;
A radiator (13) for radiating heat of the high-pressure refrigerant discharged from the compressor (11, 12, 51);
Nozzle part (16a) for decompressing and expanding the refrigerant on the downstream side of the radiator (13), refrigerant suction port (16b) for sucking the refrigerant into the interior by the refrigerant flow injected from the nozzle part (16a), ) And a suction unit (16c) for mixing the refrigerant flow sucked from the refrigerant suction port (16b), and a booster unit for converting the velocity energy of the refrigerant flow mixed in the mixing unit (16c) into pressure energy ( An ejector (16) having 16d);
A first heat exchanger (17) connected to the downstream side of the ejector (16) and exchanging heat between the refrigerant and the air blown into the air-conditioning target space;
A second heat exchanger (23) connected to the refrigerant suction port (16b) for exchanging heat between the refrigerant and the air blown into the air-conditioning target space;
A first branch passage (19) for guiding the refrigerant on the downstream side of the radiator (13) to the second heat exchanger (23);
A second branch passage (26) for guiding the high-pressure refrigerant discharged from the compressor (11, 12, 51) to the second heat exchanger (23), bypassing the radiator (13),
Path setting means (20, 27, 41, 42, 52, S102, S105, S203, S206, S210) for switching and setting a plurality of refrigerant flow paths,
The path setting means guides the high-pressure refrigerant discharged from the compressor (11, 12, 51) to the first heat exchanger (17) through the radiator (13) and the ejector (16). And the first refrigerant flow path led to the second heat exchanger (23) via the radiator (13) and the first branch passage (19), and the compressor (11, 12, 51) The high-pressure refrigerant discharged from the heat exchanger is guided to the first heat exchanger (17) through the radiator (13) and the ejector (16), and the second refrigerant passage through the second branch passage (26). 2. An ejector-type refrigeration cycle, wherein the second refrigerant flow path led to the two heat exchanger (23) is switched and set. The route setting means (20, 41, 42, 52, S203, S206, S210) is such that all the high-pressure refrigerant discharged from the compressor (11, 12, 51) passes through the second branch passage (26). 2. The ejector refrigeration cycle according to claim 1, wherein the third refrigerant flow path guided to the second heat exchanger via the second heat exchanger is settable. When a plurality of the compressors (11, 12) are provided and the second refrigerant flow path is set, the high-pressure refrigerant discharged from some of the compressors (11) becomes the radiator (13) and the ejector. The high-pressure refrigerant that is guided to the first heat exchanger (17) through (16) and discharged from the other compressor (12) passes through the second branch passage (26) to the second heat exchange. The ejector refrigeration cycle according to claim 1, wherein the ejector refrigeration cycle is guided to a vessel (23). The path setting means changes the flow direction of the high pressure refrigerant discharged from the first on-off valve (20) for opening and closing the first branch passage (19) and the other compressor (12) to the radiator (13 ) Or the switching valve (27) for switching to the second branch passage (26). The ejector refrigeration cycle according to claim 3, The path setting means opens and closes a first on-off valve (20) that opens and closes the first branch passage (19), and a discharge side of the other compressor (12) and the radiator (13). The ejector refrigeration cycle according to claim 3, further comprising a second on-off valve (42) for opening and closing between the second on-off valve (41) and the second branch passage (26). The path setting means includes a first on-off valve (20) that opens and closes the first branch passage (19), and a high-pressure refrigerant discharged from the other compressor (12) to the radiator (13) side. The ejector refrigeration cycle according to claim 1, further comprising a flow rate adjustment valve (52) that distributes to the second branch passage (26) side. The first heat exchanger (17) and the second heat exchanger (23) are arranged in series along the flow of air blown into the air-conditioning target space, and the first heat exchanger (17) is The ejector refrigeration cycle according to any one of claims 1 to 6, wherein the ejector refrigeration cycle is disposed upstream of the second heat exchanger (23) in the air flow. The ejector according to any one of claims 1 to 7, wherein the compressor (11, 12, 51) is a variable capacity compressor capable of adjusting a refrigerant discharge capacity by changing a discharge capacity. Refrigeration cycle. The compressor (11, 12, 51) is a compressor which is driven by an electric motor and whose refrigerant discharge capacity is adjusted by adjusting the rotational speed of the electric motor. The ejector-type refrigeration cycle according to any one of the above.

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