WO2023166951A1 - Dispositif à cycle de réfrigération - Google Patents

Dispositif à cycle de réfrigération Download PDF

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Publication number
WO2023166951A1
WO2023166951A1 PCT/JP2023/004540 JP2023004540W WO2023166951A1 WO 2023166951 A1 WO2023166951 A1 WO 2023166951A1 JP 2023004540 W JP2023004540 W JP 2023004540W WO 2023166951 A1 WO2023166951 A1 WO 2023166951A1
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WIPO (PCT)
Prior art keywords
refrigerant
condenser
expansion valve
dryness
compressor
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PCT/JP2023/004540
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English (en)
Japanese (ja)
Inventor
康太 武市
祐一 加見
賢吾 杉村
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株式会社デンソー
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Publication of WO2023166951A1 publication Critical patent/WO2023166951A1/fr

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60H—ARRANGEMENTS OF HEATING, COOLING, VENTILATING OR OTHER AIR-TREATING DEVICES SPECIALLY ADAPTED FOR PASSENGER OR GOODS SPACES OF VEHICLES
    • B60H1/00—Heating, cooling or ventilating [HVAC] devices
    • B60H1/22—Heating, cooling or ventilating [HVAC] devices the heat being derived otherwise than from the propulsion plant
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B6/00—Compression machines, plants or systems, with several condenser circuits
    • F25B6/04—Compression machines, plants or systems, with several condenser circuits arranged in series

Definitions

  • the present disclosure relates to a refrigeration cycle device that has two condensers and can switch between a refrigerant circulation circuit that uses one condenser and a refrigerant circulation circuit that does not use one condenser.
  • Patent Document 1 describes a refrigeration cycle device having an indoor condenser and an outdoor heat exchanger as two condensers.
  • the refrigerant discharged from the compressor flows through an outdoor heat exchanger and is condensed by the outdoor heat exchanger in a refrigerant circulation circuit, and the refrigerant discharged from the compressor bypasses the outdoor heat exchanger. It is possible to switch to a refrigerant circulation circuit that does not condense in the outdoor heat exchanger.
  • the refrigerant circulation circuit in other words, the first circulation circuit in which the refrigerant is condensed in the outdoor heat exchanger (in other words, the second condenser) is changed to the refrigerant circulation circuit (in which the refrigerant is not condensed by the outdoor heat exchanger).
  • the liquid refrigerant may remain in the outdoor heat exchanger, and the refrigerant circulating in the cycle may run short in the switched refrigerant circulation circuit.
  • the present disclosure provides liquid refrigerant in the second condenser when switching from the first circulation circuit in which the refrigerant is condensed in the second condenser to the second circulation circuit in which the refrigerant is not condensed in the second condenser.
  • the purpose is to suppress the remaining
  • a refrigeration cycle device includes a compressor, a first condenser and a second condenser, an evaporator, a first expansion valve, a second expansion valve, a refrigerant path switching section, and a control unit.
  • the compressor compresses and discharges the refrigerant.
  • a 1st condenser and a 2nd condenser heat-exchange and condense a refrigerant
  • the evaporator heat-exchanges the refrigerant to evaporate the refrigerant.
  • the first expansion valve decompresses and expands the refrigerant flowing into the second condenser.
  • the second expansion valve decompresses and expands the refrigerant flowing into the evaporator.
  • the refrigerant path switching unit includes a first circulation path through which refrigerant circulates in the order of a compressor, a first condenser, a first expansion valve, a second condenser, a second expansion valve, an evaporator, and a compressor; 1 condenser, the second expansion valve, the evaporator, and the second circulation path in which the refrigerant circulates in the order of the compressor is switched.
  • the control unit performs dryness increase control to increase the dryness of the refrigerant in the second condenser when switching from the first circulation path to the second circulation path.
  • the dryness of the refrigerant in the second condenser increases when switching from the first circulation path to the second circulation path, so the amount of liquid refrigerant in the second condenser decreases. Therefore, it is possible to prevent the liquid refrigerant from remaining in the second condenser when switching from the first circulation path to the second circulation path.
  • a refrigeration cycle device includes a compressor, a first condenser, a second condenser, an evaporator, a first expansion valve, a second expansion valve, a low-pressure refrigerant passage, A refrigerant route switching unit and a control unit are provided.
  • the compressor compresses and discharges the refrigerant.
  • the first condenser exchanges heat between the air blown into the air-conditioned space and the refrigerant, and releases heat from the refrigerant.
  • the second condenser exchanges heat between the refrigerant and the outside air.
  • the evaporator heat-exchanges the air before passing through the first condenser with the refrigerant to evaporate the refrigerant.
  • the first expansion valve decompresses and expands the refrigerant flowing into the second condenser.
  • the second expansion valve decompresses and expands the refrigerant flowing into the evaporator.
  • the low-pressure refrigerant passage bypasses the second expansion valve and the evaporator and guides the refrigerant that has flowed out of the second condenser to the suction side of the compressor.
  • the refrigerant path switching unit includes a first circulation path through which refrigerant circulates in the order of a compressor, a first condenser, a first expansion valve, a second condenser, a second expansion valve, an evaporator, and a compressor;
  • the second circulation path through which the refrigerant circulates in the order of the first condenser, the second expansion valve, the evaporator, and the compressor is switched, and the low-pressure refrigerant passage is opened and closed.
  • the control unit controls the refrigerant path switching unit so that the low-pressure refrigerant passage opens when switching from the first circulation path to the second circulation path.
  • the outlet side of the second condenser is connected to the low-pressure refrigerant circuit, so the refrigerant inside the second condenser is actively discharged, and the inside of the second condenser of liquid refrigerant is further reduced. Therefore, it is possible to prevent the liquid refrigerant from remaining in the second condenser when switching from the first circulation path to the second circulation path.
  • FIG. 4 is a time chart showing an example of control processing executed by the control device of the refrigeration cycle apparatus of the first embodiment;
  • FIG. 4 is a Mollier diagram showing changes in the state of refrigerant in the refrigeration cycle apparatus of the first embodiment; It is a graph explaining the upper limit storage amount in the dryness increase control of the first embodiment.
  • FIG. 7 is a graph for explaining the lower limit of dryness in the dryness increasing control of the first embodiment; 9 is a time chart showing an example of control processing executed by the control device of the refrigeration cycle apparatus of the second embodiment; 9 is a time chart showing an example of control processing executed by a control device for a refrigeration cycle apparatus according to a third embodiment; It is a whole block diagram which shows the refrigerating-cycle apparatus of 4th Embodiment. It is a whole block diagram which shows the refrigerating-cycle apparatus of 5th Embodiment. It is a whole block diagram which shows the refrigerating-cycle apparatus of 6th Embodiment.
  • a refrigeration cycle apparatus 10 of the present embodiment will be described with reference to the drawings.
  • a refrigeration cycle device 10 shown in FIG. 1 is applied to a vehicle air conditioner for a hybrid vehicle.
  • a vehicle air conditioner to which the refrigeration cycle device 10 is applied cools or heats air blown into a vehicle interior, which is a space to be air-conditioned.
  • the refrigeration cycle device 10 can be switched between a cooling mode refrigerant flow path, a dehumidifying heating mode refrigerant flow path, and a heating mode refrigerant flow path.
  • the cooling mode is an operation mode during cooling operation for cooling the vehicle interior.
  • the dehumidification/heating mode is an operation mode during dehumidification operation in which heating is performed while dehumidifying the vehicle interior.
  • the heating mode is an operation mode during heating operation for heating the vehicle interior.
  • the refrigeration cycle device 10 can execute a first dehumidifying and heating mode, a second dehumidifying and heating mode, and a third dehumidifying and heating mode as dehumidifying and heating modes.
  • the refrigerant in the refrigeration cycle device 10 is a freon-based refrigerant
  • the refrigeration cycle device 10 is configured as a subcritical refrigeration cycle in which the pressure of the high-pressure refrigerant does not exceed the critical pressure of the refrigerant.
  • the refrigeration cycle device 10 includes a compressor 11, an indoor condenser 12, a first refrigerant passage 13, a first expansion valve 14, an outdoor heat exchanger 15, a second refrigerant passage 16, a first on-off valve 17, and a third refrigerant passage 18. , a second expansion valve 19, an indoor evaporator 20, an accumulator 21, a bypass passage 22, a second on-off valve 23, a check valve 24, a constant pressure valve 25, a control device 40, and the like.
  • the compressor 11 is arranged in the engine room of the vehicle, sucks the refrigerant in the refrigeration cycle device 10, compresses it, and discharges it.
  • the compressor 11 is an electric compressor that includes an electric motor and a compression mechanism that is driven by the electric motor and compresses a refrigerant, and that changes compression power in accordance with the rotation speed of the electric motor.
  • the compression mechanism of the compressor 11 is, for example, various compression mechanisms such as a scroll compression mechanism or a vane compression mechanism.
  • the inlet side of the indoor condenser 12 is connected to the outlet side of the compressor 11 .
  • the indoor condenser 12 is arranged inside the casing 31 of the indoor air conditioning unit 30 .
  • the indoor condenser 12 is a first condenser that causes the high-pressure refrigerant discharged from the compressor 11 to exchange heat with the air that is blown into the vehicle interior to condense the refrigerant, thereby releasing heat from the high-pressure refrigerant.
  • a first refrigerant passage 13 that guides the refrigerant flowing out of the indoor condenser 12 to the outdoor heat exchanger 15 is connected to the outlet side of the indoor condenser 12 .
  • a first expansion valve 14 configured to change the passage area of the first refrigerant passage 13 is arranged in the first refrigerant passage 13 .
  • the first expansion valve 14 is an electric variable throttle mechanism that includes a valve body that can change the throttle opening and an electric actuator that is a stepping motor that changes the throttle opening of the valve body.
  • the first expansion valve 14 increases or decreases the throttle opening degree of the first expansion valve 14 according to a control signal output from the control device 40 .
  • the passage area of the first refrigerant passage 13 increases as the throttle opening of the first expansion valve 14 increases.
  • the first expansion valve 14 decompresses and expands the refrigerant passing through it by throttling it according to the opening degree of the throttle.
  • the first expansion valve 14 allows the refrigerant to pass through without being decompressed and expanded.
  • the first expansion valve 14 blocks the flow of the refrigerant in the fully closed state so that the refrigerant does not flow into the outdoor heat exchanger 15 .
  • the inlet side of the outdoor heat exchanger 15 is connected to the outlet side of the first expansion valve 14 .
  • the outdoor heat exchanger 15 is a refrigerant outside air heat exchanger that exchanges heat between the refrigerant and the outside air.
  • the outdoor heat exchanger 15 functions as an evaporator that evaporates the refrigerant to exhibit heat absorption in the heating mode, etc., and functions as a second condenser that condenses the refrigerant to exhibit the heat dissipation effect in the cooling mode, etc.
  • a second refrigerant passage 16 and a third refrigerant passage 18 are connected to the outlet side of the outdoor heat exchanger 15 .
  • the second refrigerant passage 16 is a low-pressure refrigerant passage that guides the refrigerant that has flowed out of the outdoor heat exchanger 15 to the inlet side of the accumulator 21 .
  • the third refrigerant passage 18 is a refrigerant passage that guides the refrigerant that has flowed out of the outdoor heat exchanger 15 to the inlet side of the indoor evaporator 20 .
  • a first on-off valve 17 is arranged in the second refrigerant passage 16 .
  • the first on-off valve 17 is an electromagnetic valve that opens and closes the second refrigerant passage 16 .
  • the first on-off valve 17 is a refrigerant path switching unit that switches refrigerant paths. Operation of the first on-off valve 17 is controlled by a control signal output from the control device 40 .
  • a second expansion valve 19 configured to change the passage area of the third refrigerant passage 18 is arranged in the third refrigerant passage 18 .
  • the second expansion valve 19 is an electric variable throttle mechanism similar to the first expansion valve 14 , and increases or decreases the throttle opening of the second expansion valve 19 according to a control signal output from the control device 40 . Specifically, the second expansion valve 19 decompresses and expands the refrigerant by throttling the passing refrigerant according to the opening degree of the throttle. The second expansion valve 19 allows the refrigerant to pass through without being decompressed and expanded in the fully open state. The second expansion valve 19 blocks the flow of the refrigerant in the fully closed state.
  • the inlet side of the indoor evaporator 20 is connected to the outlet side of the second expansion valve 19 .
  • the indoor evaporator 20 is arranged on the air flow upstream side of the indoor condenser 12 in the casing 31 of the indoor air conditioning unit 30 .
  • Refrigerant flows through the indoor evaporator 20 in, for example, the cooling mode and the dehumidifying and heating mode.
  • the indoor evaporator 20 is an evaporator that cools the air by exchanging heat with the air that has not passed through the indoor condenser 12 to evaporate the refrigerant that flows through the interior of the indoor evaporator 20, thereby exerting an endothermic effect.
  • the outlet side of the indoor evaporator 20 is connected to the inlet side of the accumulator 21 via a constant pressure valve 25 .
  • the constant pressure valve 25 is a mechanical decompression device that mechanically decompresses the refrigerant passing through it. Specifically, the constant pressure valve 25 reduces the pressure of the refrigerant passing through it while maintaining the pressure of the refrigerant on the outlet side of the indoor evaporator 20 at a predetermined value.
  • the accumulator 21 is a gas-liquid separator that separates the gas-liquid refrigerant that has flowed into it and stores excess refrigerant in the cycle.
  • the gas-phase refrigerant outlet of the accumulator 21 is connected to the suction port side of the compressor 11 .
  • the accumulator 21 suppresses the liquid-phase refrigerant from being sucked into the compressor 11 and prevents liquid compression in the compressor 11 .
  • the refrigeration cycle device 10 is provided with a bypass passage 22 that guides the refrigerant on the upstream side of the first expansion valve 14 to the inlet side of the second expansion valve 19 in the first refrigerant passage 13 .
  • the bypass passage 22 is a refrigerant passage that guides the refrigerant flowing out of the indoor condenser 12 to the inlet side of the second expansion valve 19 by bypassing the first expansion valve 14 and the outdoor heat exchanger 15 .
  • a second on-off valve 23 is arranged in the bypass passage 22 .
  • the second on-off valve 23 is an electromagnetic valve that opens and closes the bypass passage 22 .
  • the second on-off valve 23 is a refrigerant path switching unit that switches refrigerant paths. The operation of the second on-off valve 23 is controlled by a control signal output from the controller 40 .
  • a check valve 24 is arranged on the upstream side of the confluence with the bypass passage 22.
  • the check valve 24 allows the refrigerant to flow from the outlet side of the outdoor heat exchanger 15 to the inlet side of the second expansion valve 19, while allowing the refrigerant to flow from the inlet side of the second expansion valve 19 to the outlet of the outdoor heat exchanger 15. Prohibit the flow of refrigerant to the side.
  • the check valve 24 prevents the refrigerant that has joined the third refrigerant passage 18 from the bypass passage 22 from flowing toward the outdoor heat exchanger 15 .
  • the indoor air conditioning unit 30 is arranged inside the instrument panel in the frontmost part of the vehicle interior.
  • a casing 31 forming an outer shell of the indoor air conditioning unit 30 accommodates a blower 32, a heater core 34, an indoor condenser 12, an indoor evaporator 20, and the like.
  • the casing 31 forms a passage for the air blown into the passenger compartment, and is molded from a resin (for example, polypropylene) that has a certain degree of elasticity and excellent strength.
  • An inside/outside air switching device 33 is arranged on the most upstream side of the air flow inside the casing 31 to switch between the outside air, which is the air outside the vehicle compartment, and the inside air, which is the air inside the vehicle compartment.
  • the inside/outside air switching device 33 is formed with an inside air introduction port for introducing inside air into the casing 31 and an outside air introduction port for introducing outside air. Inside the inside/outside air switching device 33, an inside/outside air switching door is arranged that adjusts the opening areas of the inside air introduction port and the outside air introduction port to change the air volume ratio between the inside air volume and the outside air volume.
  • a blower 32 that blows the air introduced via the inside/outside air switching device 33 toward the vehicle interior is arranged downstream of the inside/outside air switching device 33 in the air flow.
  • the blower 32 is, for example, an electric sirocco fan.
  • the amount of air blown by the blower 32 is controlled by a control signal output from the control device 40 .
  • the indoor evaporator 20, the heater core 34, and the indoor condenser 12 are arranged in this order in the air flow direction downstream of the blower 32 in the air flow.
  • the indoor evaporator 20 is arranged on the upstream side of the air flow with respect to the indoor condenser 12 and the heater core 34 .
  • the heater core 34 is a heating heat exchanger that exchanges heat between the cooling water of the engine that outputs the driving force for running the vehicle and the air that is blown into the vehicle interior.
  • the heater core 34 is arranged on the upstream side of the air flow with respect to the indoor condenser 12 .
  • a cold air bypass passage 35 is formed in the casing 31 so that the air that has passed through the indoor evaporator 20 bypasses the indoor condenser 12 and the heater core 34 .
  • An air mix door 36 is arranged to adjust the air volume ratio with the air passing through the cold air bypass passage 35 .
  • a mixing space for mixing the air that has passed through the indoor condenser 12 and the air that has passed through the cold wind bypass passage 35 is provided on the downstream side of the indoor condenser 12 and the downstream side of the cold wind bypass passage 35 in the air flow. .
  • An air outlet for blowing out air into the vehicle interior is provided on the most downstream side of the blown air flow of the casing 31, and the conditioned air mixed in the mixing space is blown into the vehicle interior through the air outlet.
  • the air mix door 36 is driven by a servomotor (not shown) operated by a control signal output from the controller 40 .
  • the refrigeration cycle apparatus 10 includes a first temperature sensor 42, a first pressure sensor 44, a second temperature sensor 46, a third temperature sensor 48, a fourth temperature sensor 50 and an outside air temperature sensor 52, as shown in FIG. there is
  • the first temperature sensor 42 and the first pressure sensor 44 are provided between the indoor condenser 12 and the first expansion valve 14 in the first refrigerant passage 13 .
  • the first temperature sensor 42 detects the temperature of the refrigerant that has flowed out of the indoor condenser 12 .
  • a first pressure sensor 44 detects the pressure of the refrigerant that has flowed out of the indoor condenser 12 .
  • the second temperature sensor 46 is provided at the refrigerant outlet of the outdoor heat exchanger 15 and detects the temperature of the refrigerant flowing out of the outdoor heat exchanger 15 .
  • the third temperature sensor 48 is provided downstream of the indoor evaporator 20 in the air flow inside the casing 31 of the indoor air conditioning unit 30, and is the temperature Te of the air blown out from the indoor evaporator 20 (hereinafter referred to as the evaporator outlet temperature Te). say.) is detected.
  • the fourth temperature sensor 50 is provided in the refrigerant flow path from the indoor evaporator 20 to the constant pressure valve 25 and detects the temperature of the refrigerant flowing out from the indoor evaporator 20 .
  • the outside air temperature sensor 52 is provided outside the passenger compartment and detects the outside air temperature Tam.
  • the control device 40 is an electronic control device composed of a microcomputer comprising a CPU, ROM, RAM, etc. and its peripheral circuits.
  • the control device 40 is a control unit that executes various control processes according to a computer program pre-stored in a ROM or the like.
  • a detection signal representing a detection value is input to the control device 40 from each sensor 42 , 44 , 46 , 48 , 50 , 52 .
  • the control device 40 receives detection signals representing detection values from various sensors for air conditioning control, such as an inside air sensor, a solar radiation sensor, a discharge temperature sensor, and a blowout temperature sensor.
  • the internal air sensor detects the vehicle interior temperature Tr.
  • a solar radiation sensor detects the amount of solar radiation Ts in the passenger compartment.
  • a discharge temperature sensor detects the temperature Td of the refrigerant discharged from the compressor 11 .
  • the blowout temperature sensor detects the blowout temperature TAV of the air blown out from the indoor air conditioning unit 30 into the vehicle interior.
  • An operation panel (not shown) arranged on the instrument panel is connected to the control device 40, and operation signals are input from various operation switches provided on the operation panel.
  • Various operation switches provided on the operation panel include an air conditioner switch for setting whether or not to cool the air in the indoor air conditioning unit 30, a temperature setting switch for setting the preset temperature in the passenger compartment, and the like.
  • the air conditioner switch is turned on by the occupant when the vehicle air conditioner is in cooling operation or dehumidifying operation. That is, when the air conditioner switch is on, the air is cooled by the indoor evaporator 20 in the cooling mode or the dehumidifying and heating mode.
  • the air conditioner switch When the air conditioner switch is off, the air is heated by the indoor condenser 12 without being cooled by the indoor evaporator 20 in the heating mode.
  • the control device 40 sets the operation mode of the vehicle air conditioner to any one of the cooling mode, the first dehumidifying heating mode, the second dehumidifying heating mode, and the third dehumidifying heating mode based on the target air temperature TAO. decide whether
  • the target blowout temperature TAO is determined by the vehicle interior set temperature Tset set by the temperature setting switch in the operation panel, the vehicle interior temperature Tr detected by the inside air sensor, the outside air temperature Tam detected by the outside air temperature sensor 52, and the solar radiation sensor. It is calculated from a predetermined calculation formula based on the detected solar radiation amount Ts.
  • the control device 40 determines the operation mode of the vehicle air conditioner to be the cooling mode.
  • the cooling reference temperature ⁇ is the maximum value of the target outlet temperature TAO to be achieved in the cooling mode.
  • the control device 40 determines the operation mode of the vehicle air conditioner to be the first dehumidifying and heating mode. .
  • the first judgment value T1 is the maximum value of the target blowout temperature TAO to be achieved in the first dehumidifying and heating mode.
  • the first determination value T1 is a value greater than the cooling reference temperature ⁇ .
  • the controller 40 determines that the heating capacity of the indoor condenser 12 is insufficient due to the dehumidifying operation in the first dehumidifying and heating mode. It determines that it is, and determines the operation mode of the vehicle air conditioner to be either the second dehumidifying/heating mode or the third dehumidifying/heating mode.
  • the second dehumidifying and heating mode is determined.
  • the second determination value T2 is the minimum value of the target blowout temperature TAO to be achieved in the second dehumidifying and heating mode.
  • the second determination value T2 is a value equal to or greater than the first determination value T1.
  • the third dehumidification and heating mode is determined. That is, when trying to match the blow-out temperature TAV into the passenger compartment with the target blow-out temperature TAO while maintaining the required dehumidifying capacity of the indoor evaporator 20, the second dehumidifying/heating mode dehumidifies. It is determined that the heating capacity of the indoor condenser 12 will be excessive if it is operated, and the third dehumidifying and heating mode is determined.
  • the control device 40 shuts off the second refrigerant passage 16 with the first on-off valve 17, shuts off the bypass passage 22 with the second on-off valve 23, and fully opens the first expansion valve 14.
  • the controller 40 allows the refrigerant discharged from the compressor 11 to flow through the indoor condenser 12, the first expansion valve 14, the outdoor heat exchanger 15, and the check valve 24, as indicated by the white arrows in FIG. , the second expansion valve 19 , the indoor evaporator 20 , the constant pressure valve 25 and the accumulator 21 , and return to the compressor 11 .
  • control device 40 closes the air passages of the heater core 34 and the indoor condenser 12 with the air mix door 36 so that the entire flow of the blown air after passing through the indoor evaporator 20 is directed to the cold air bypass passage 35. will flow.
  • the refrigerant that has flowed into the indoor condenser 12 flows out of the indoor condenser 12 without substantially exchanging heat with air.
  • the control device 40 refers to a control map stored in advance in the control device 40 based on the target outlet temperature TAO, and sets the target evaporator temperature, which is the target value of the air temperature blown out from the indoor evaporator 20. Determine the outlet temperature TEO. Then, based on the deviation between the target evaporator outlet temperature TEO and the evaporator outlet temperature Te detected by the third temperature sensor 48, the compressor 11 is adjusted so that the outlet temperature TAV into the passenger compartment approaches the target outlet temperature TAO. to control the rotation speed of the
  • the control device 40 controls the degree of supercooling of the refrigerant flowing into the second expansion valve 19 to approach a predetermined target degree of supercooling so that the coefficient of performance (hereinafter referred to as COP) of the cycle approaches the maximum value.
  • the throttle opening degree of the second expansion valve 19 is controlled.
  • the degree of subcooling of the refrigerant flowing into the second expansion valve 19 is, for example, the refrigerant temperature at the outlet of the outdoor heat exchanger 15 detected by the second temperature sensor 46 and the outdoor heat exchange temperature detected by the first pressure sensor 44. It is calculated from the refrigerant pressure at the outlet of the vessel 15 .
  • the first expansion valve 14 is fully open, the pressure of the refrigerant at the outlet of the outdoor heat exchanger 15 can be detected by the first pressure sensor 44 provided at the outlet of the indoor condenser 12 .
  • the air mix door 36 closes the air passage of the indoor condenser 12 and the heater core 34, so the air cooled by the indoor evaporator 20 can be blown out into the passenger compartment. Thereby, cooling of the passenger compartment can be achieved.
  • the control device 40 blocks the second refrigerant passage 16 by the first on-off valve 17, blocks the bypass passage 22 by the second on-off valve 23, and closes the first expansion valve 14 and the second expansion valve. 19 and 19 are respectively in a throttled state or a fully open state.
  • the controller 40 allows the refrigerant discharged from the compressor 11 to flow through the indoor condenser 12, the first expansion valve 14, the outdoor heat exchanger 15, and the check valve, as indicated by the white horizontal line arrows in FIG. 24 , the second expansion valve 19 , the indoor evaporator 20 , the constant pressure valve 25 and the accumulator 21 to establish a first circulation path returning to the compressor 11 .
  • the outdoor heat exchanger 15 and the indoor evaporator 20 are connected in series in the refrigerant flow.
  • the first circulation route is the same route as the cooling circulation route described above.
  • the controller 40 controls the rotation speed of the compressor 11 in the same manner as in the cooling mode.
  • the control device 40 closes the cold air bypass passage 35 with the air mix door 36, so that the entire flow rate of the blown air after passing through the indoor evaporator 20 passes through the heater core 34 and the air passage of the indoor condenser 12. make it
  • the control device 40 changes the throttle opening degree of the first expansion valve 14 and the throttle opening degree of the second expansion valve 19 according to the target blowout temperature TAO. Specifically, the controller 40 causes the first expansion valve 14 to reduce the passage area of the first refrigerant passage 13 and causes the second expansion valve 19 to reduce the passage area of the third refrigerant passage 13 as the target blowout temperature TAO rises. Increase the passage area of the passage 18.
  • the outdoor heat exchanger 15 in the first dehumidifying and heating mode may function as an evaporator or may function as a condenser.
  • the outdoor heat exchanger 15 is arranged upstream of the indoor evaporator 20 in the refrigerant flow, and from the viewpoint of preventing the indoor evaporator 20 from frosting, the refrigerant pressure of the indoor evaporator 20 is set to 0°C. Since the pressure cannot be lowered below the saturation pressure, the refrigerant pressure in the outdoor heat exchanger 15 cannot be lowered below the 0° C. saturation pressure.
  • the outdoor air temperature Tam is extremely low, such as below freezing point, even if the second expansion valve 19 is fully opened or substantially fully opened to reduce the temperature of the refrigerant in the outdoor heat exchanger 15 to the lowest possible level, the outdoor air temperature Tam is lower than the refrigerant temperature of the outdoor heat exchanger 15, and the outdoor heat exchanger 15 functions as a condenser.
  • the air that has been cooled and dehumidified by the indoor evaporator 20 can be heated by the indoor condenser 12 and blown out into the passenger compartment. As a result, dehumidification and heating of the passenger compartment can be realized.
  • the control device 40 opens the second refrigerant passage 16 by opening the first on-off valve 17, opens the bypass passage 22 by opening the second on-off valve 23, and opens the first expansion valve 14 and The second expansion valve 19 and the second expansion valve 19 are respectively throttled. As a result, the control device 40 establishes the second circulation path indicated by the outline hatched arrows in FIG.
  • the second circulation path is the refrigerant discharged from the compressor 11 flows to the indoor condenser 12, and from the indoor condenser 12, the first expansion valve 14, the outdoor heat exchanger 15, the first on-off valve 17, and the accumulator 21. While flowing in order, the refrigerant flows in order from the indoor condenser 12 to the second on-off valve 23, the second expansion valve 19, the indoor evaporator 20, the constant pressure valve 25, and the accumulator 21. is the route back to That is, in the second circulation path, the outdoor heat exchanger 15 and the indoor evaporator 20 are connected in parallel in the refrigerant flow. Therefore, in the refrigeration cycle of the second dehumidifying and heating mode, the outdoor heat exchanger 15 always functions as an evaporator.
  • the action of the check valve 24 prevents the refrigerant from flowing back from the bypass passage 22 to the outlet side of the outdoor heat exchanger 15 . Also, due to the action of the constant pressure valve 25 , the refrigerant pressure inside the indoor evaporator 20 is maintained higher than the refrigerant pressure inside the outdoor heat exchanger 15 .
  • control device 40 controls the rotation speed of the compressor 11 so that the air temperature TAV into the passenger compartment approaches the target air temperature TAO, and closes the cold air bypass passage 35 with the air mix door 36. do.
  • the control device 40 adjusts the respective throttle opening degrees so that the throttle opening degrees of the first expansion valve 14 and the throttle opening degrees of the second expansion valve 19 become predetermined opening degrees for the second dehumidifying and heating mode. control the electric actuator that adjusts the
  • the refrigerant flow path is such that the outdoor heat exchanger 15 and the indoor evaporator 20 are connected in parallel with respect to the refrigerant flow.
  • the refrigerant flow rate to the evaporator 20 can be reduced. Therefore, the amount of heat absorbed by the refrigerant in the indoor evaporator 20 can be reduced, and the temperature of the air dehumidified by the indoor evaporator 20 in the indoor condenser 12 can be adjusted in a higher temperature range than in the first dehumidifying and heating mode. can be done.
  • control device 40 closes the first on-off valve 17 to block the second refrigerant passage 16, opens the second on-off valve 23 to open the bypass passage 22, and opens the first expansion valve 14. is fully closed to prevent the refrigerant from flowing into the outdoor heat exchanger 15, and the second expansion valve 19 is throttled.
  • the controller 40 causes the refrigerant discharged from the compressor 11 to flow through the indoor condenser 12, the second on-off valve 23, the second expansion valve 19, and the indoor evaporator, as indicated by the dotted arrows in FIG. 20 , constant pressure valve 25 , accumulator 21 , and returns to compressor 11 .
  • the action of the check valve 24 prevents the refrigerant from flowing back from the bypass passage 22 to the outlet side of the outdoor heat exchanger 15 .
  • the pressure of the refrigerant inside the indoor evaporator 20 is maintained at a constant pressure by the action of the constant pressure valve 25 .
  • the refrigerant pressure in the indoor evaporator 20 is maintained at a predetermined pressure higher than the 0° C. saturation pressure so as to prevent frosting of the indoor evaporator 20 .
  • the control device 40 controls the rotational speed of the compressor 11 and closes the cold air bypass passage 35 with the air mix door 36 in the same manner as in the first dehumidifying and heating mode.
  • the control device 40 increases the rotational speed of the compressor 11 to increase the compression power of the compressor 11, so that the heat dissipation capacity of the indoor condenser 12 to dissipate heat from the refrigerant, in other words, the heating capacity of the indoor condenser 12 can be increased. That is, it is possible to control the heating capacity while preventing the indoor evaporator 20 from frosting.
  • control device 40 can increase the heating capacity of the indoor condenser 12 by increasing the compression power of the compressor 11 while maintaining the refrigerant pressure in the indoor evaporator 20 constant. can.
  • control device 40 operates an electric actuator that adjusts the throttle opening so that the throttle opening of the second expansion valve 19 becomes a predetermined opening for the third dehumidifying and heating mode. Control.
  • the heat exchange amount of the outdoor heat exchanger 15 becomes zero. Therefore, in the third dehumidifying and heating mode, intermediate heating capacity between the first dehumidifying and heating mode and the second dehumidifying and heating mode can be obtained.
  • the operation mode of the vehicle air conditioner is changed to the third dehumidification and heating mode in addition to the first dehumidification and heating mode and the second dehumidification and heating mode. can be switched, it is possible to smoothly control the blow-out temperature TAV into the passenger compartment while maintaining the required dehumidification capability.
  • the control device 40 opens the second refrigerant passage 16 by opening the first on-off valve 17, shuts off the bypass passage 22 with the second on-off valve 23, and puts the first expansion valve 14 in the throttle state. Furthermore, the second expansion valve 19 is fully closed, thereby preventing the refrigerant from flowing into the indoor evaporator 20 . Then, the first expansion valve 14 is throttled. As a result, the controller 40 allows the refrigerant discharged from the compressor 11 to flow through the indoor condenser 12, the first expansion valve 14, the outdoor heat exchanger 15, and the first on-off valve, as indicated by the black arrows in FIG. 17 and accumulator 21 to establish a heating circulation path returning to the compressor 11 . In the heating circulation path, the outdoor heat exchanger 15 functions as an evaporator.
  • control device 40 controls the rotational speed of the compressor 11 so that the temperature TAV of air blown into the vehicle interior approaches the target air temperature TAO, and the air mix door 36 The cold air bypass passage 35 is blocked.
  • the control device 40 adjusts the degree of throttle opening of the first expansion valve 14 so that the degree of supercooling of the refrigerant flowing into the first expansion valve 14 approaches a predetermined target degree of supercooling so as to bring the COP closer to the maximum value. to control.
  • the degree of supercooling of the refrigerant flowing into the first expansion valve 14 is, for example, the temperature of the refrigerant at the outlet of the indoor condenser 12 detected by the first temperature sensor 42 and the temperature of the indoor condenser 12 detected by the first pressure sensor 44. is calculated from the refrigerant pressure at the outlet of .
  • the indoor condenser 12 radiates the heat of the high-pressure refrigerant discharged from the compressor 11 to the air, and the heater core 34 radiates the heat of the cooling water to the air, The heated air can be blown into the passenger compartment. This makes it possible to heat the vehicle interior.
  • control device 40 When switching from the first dehumidification/heating mode to the third dehumidification/heating mode, the control device 40 performs dryness increase control as shown in the time chart of FIG.
  • FIG. 3 is a Mollier chart showing changes in the state of the refrigerant in the refrigeration cycle device 10 due to dryness increase control.
  • a two-dot chain line in FIG. 3 indicates a change in the state of the refrigerant in the refrigeration cycle device 10 before the dryness increase control is executed.
  • the dryness of the refrigerant at the inlet of the outdoor heat exchanger 15 is increased, and the dryness of the refrigerant flowing into the outdoor heat exchanger 15 is increased. Therefore, the liquid refrigerant inside the outdoor heat exchanger 15 is reduced. As a result, it is possible to prevent a shortage of the refrigerant circulating in the refrigerant circulation path in the third dehumidifying and heating mode.
  • the outlet side of the outdoor heat exchanger 15 is connected to the low-pressure refrigerant circuit, so the refrigerant inside the outdoor heat exchanger 15 is actively discharged, and the inside of the outdoor heat exchanger 15 Liquid refrigerant is further reduced.
  • the shortage of the refrigerant circulating in the refrigerant circulation path in the third dehumidifying and heating mode can be further suppressed.
  • the control device 40 sets the opening degree of the throttle of the first expansion valve 14 to an opening degree at which the dryness of the refrigerant in the outdoor heat exchanger 15 is equal to or higher than the lower limit dryness Xmin.
  • the control device 40 performs the dryness increasing control until the dryness of the refrigerant in the outdoor heat exchanger 15 reaches or exceeds the minimum dryness Xmin.
  • the lower limit dryness Xmin is the dryness when the amount of refrigerant stored in the outdoor heat exchanger 15 (hereinafter referred to as the amount of refrigerant stored) reaches the upper limit storage amount Rmax.
  • the upper limit storage amount Rmax is a refrigerant amount determined so that the refrigerant does not run short in the third dehumidifying and heating mode.
  • the upper limit storage amount Rmax is the amount of refrigerant that is obtained by subtracting the amount of refrigerant required in the third dehumidifying and heating mode from the amount of refrigerant enclosed in the refrigeration cycle device 10 .
  • FIG. 5 is a graph showing the correlation between the amount of liquid refrigerant stored in the outdoor heat exchanger 15 of the present embodiment and the dryness of the refrigerant (specifically, the average dryness).
  • the threshold value of the amount of refrigerant that can be stored in the outdoor heat exchanger 15 depends on the amount of refrigerant charged in the refrigeration cycle device 10 and the amount of refrigerant required in the third dehumidifying and heating mode (in other words, the operation mode to be switched to). Determined.
  • the amount of refrigerant stored in the outdoor heat exchanger 15 has a correlation with the average dryness in the outdoor heat exchanger 15 and the volume of the outdoor unit.
  • the upper limit storage amount Rmax is determined from the amount of refrigerant charged in the refrigeration cycle device 10, and control is performed so that the upper limit storage amount Rmax is equal to or higher than the uniquely determined lower limit dryness Xmin.
  • the shortage of the refrigerant circulating in the refrigerant circulation path in the third dehumidifying and heating mode can be reliably suppressed.
  • control device 40 performs dryness increase control when switching from the first dehumidifying and heating mode to the third dehumidifying and heating mode. Dryness increase control is control for increasing the dryness of the refrigerant in the outdoor heat exchanger 15 .
  • the outdoor heat when switching from the first dehumidification heating mode to the third dehumidification heating mode It is possible to suppress the liquid refrigerant from remaining in the exchanger 15 . Therefore, it is possible to suppress the shortage of the refrigerant circulating in the refrigerant circulation path in the third dehumidifying and heating mode.
  • the control device 40 controls the first on-off valve 17 so that the second refrigerant passage 16 opens when switching from the first dehumidifying and heating mode to the third dehumidifying and heating mode.
  • the outlet side of the outdoor heat exchanger 15 is connected to the second refrigerant passage 16 (in other words, the low-pressure refrigerant circuit), so the refrigerant inside the outdoor heat exchanger 15 is actively discharged, and the liquid refrigerant inside the outdoor heat exchanger 15 is further reduced. Therefore, it is possible to further suppress the shortage of the refrigerant circulating in the refrigerant circulation path in the third dehumidifying and heating mode.
  • control device 40 increases the throttle opening of the first expansion valve 14 to a degree at which the dryness of the refrigerant in the outdoor heat exchanger 15 is equal to or higher than the minimum dryness Xmin in the dryness increase control. do.
  • the shortage of the refrigerant circulating in the refrigerant circulation path in the third dehumidifying and heating mode can be reliably suppressed.
  • control device 40 performs the dryness increasing control until the dryness of the refrigerant in the outdoor heat exchanger 15 reaches or exceeds the minimum dryness Xmin.
  • the flow rate of the refrigerant discharged from the compressor 11 is decreased, and the flow rate of the refrigerant flowing into the first expansion valve 14 is decreased. becomes relatively large.
  • the dryness of the refrigerant at the inlet of the outdoor heat exchanger 15 increases, and the dryness of the refrigerant flowing into the outdoor heat exchanger 15 increases. Therefore, the liquid refrigerant inside the outdoor heat exchanger 15 is reduced.
  • the outlet side of the outdoor heat exchanger 15 is connected to the low-pressure refrigerant circuit, so the refrigerant inside the outdoor heat exchanger 15 is actively discharged, and the inside of the outdoor heat exchanger 15 Liquid refrigerant is further reduced. As a result, it is possible to prevent a shortage of the refrigerant circulating in the refrigerant circulation path in the third dehumidifying and heating mode.
  • the degree of opening of the first expansion valve 14 is not lowered in the dryness increase control of the present embodiment. This is for suppressing a decrease in the dryness of the refrigerant due to a decrease in the degree of opening of the first expansion valve 14 .
  • the flow rate of the refrigerant discharged from the compressor 11 is decreased, and the flow rate of the refrigerant flowing into the first expansion valve 14 is decreased. becomes relatively large.
  • the dryness of the refrigerant at the inlet of the outdoor heat exchanger 15 increases, and the dryness of the refrigerant flowing into the outdoor heat exchanger 15 increases. Therefore, the liquid refrigerant inside the outdoor heat exchanger 15 is reduced. As a result, it is possible to prevent a shortage of the refrigerant circulating in the refrigerant circulation path in the third dehumidifying and heating mode.
  • the pressure on the outlet side of the outdoor heat exchanger 15 is lowered, so the refrigerant inside the outdoor heat exchanger 15 is actively discharged, and the inside of the outdoor heat exchanger 15 of liquid refrigerant is further reduced.
  • the shortage of the refrigerant circulating in the refrigerant circulation path in the third dehumidifying and heating mode can be further suppressed.
  • the refrigeration cycle device 10 of this embodiment includes a fourth refrigerant passage 26, a third expansion valve 27 and a chiller 28. As shown in FIG. 8,
  • the fourth refrigerant passage 26 is connected in parallel with the third refrigerant passage 18 to the outlet side of the outdoor heat exchanger 15 .
  • the fourth refrigerant passage 26 is a refrigerant passage that guides the refrigerant that has flowed out of the outdoor heat exchanger 15 to the inlet side of the indoor evaporator 20 .
  • a third expansion valve 27 configured to change the passage area of the fourth refrigerant passage 26 is arranged in the fourth refrigerant passage 26 .
  • the third expansion valve 27 is an electric variable throttle mechanism similar to the first expansion valve 14 , and increases or decreases the throttle opening of the third expansion valve 27 according to a control signal output from the control device 40 . Specifically, the third expansion valve 27 decompresses and expands the refrigerant by throttling the passing refrigerant according to the opening degree of the throttle.
  • the third expansion valve 27 allows the refrigerant to pass through without being decompressed and expanded in the fully open state.
  • the third expansion valve 27 blocks the flow of the refrigerant in the fully closed state.
  • the inlet side of the chiller 28 is connected to the outlet side of the third expansion valve 27 .
  • the chiller 28 is a battery cooler that cools the battery mounted on the vehicle. Refrigerant flows through the chiller 28 during, for example, the battery cooling mode and the battery cooling heating mode.
  • the chiller 28 is an evaporator that cools the battery by evaporating the refrigerant flowing through the inside thereof with the heat of the battery and exerting an endothermic effect.
  • the outlet side of the indoor evaporator 20 is connected to the inlet side of the accumulator 21 .
  • the refrigeration cycle device 10 performs a battery cooling mode and a heating battery cooling mode in addition to the same cooling mode, first dehumidifying heating mode, second dehumidifying heating mode, third dehumidifying heating mode and heating mode as in the above embodiment. be able to.
  • the control device 40 shuts off the second refrigerant passage 16 by the first on-off valve 17, shuts off the bypass passage 22 by the second on-off valve 23, fully opens the first expansion valve 14, and opens the second The expansion valve 19 is fully closed to prevent the refrigerant from flowing into the evaporator 20 .
  • the controller 40 causes the refrigerant discharged from the compressor 11 to flow through the indoor condenser 12, the first expansion valve 14, the outdoor heat exchanger 15, and the check valve 24, as indicated by the white arrows in FIG. , the third expansion valve 27 and the chiller 28 in this order to establish a cooling circulation path returning to the compressor 11 .
  • the control device 40 stops the blower 32.
  • the refrigerant that has flowed into the indoor condenser 12 flows out of the indoor condenser 12 without substantially exchanging heat with air.
  • the outdoor heat exchanger 15 functions as a condenser
  • the chiller 28 functions as an evaporator.
  • the control device 40 shuts off the second refrigerant passage 16 by the first on-off valve 17, shuts off the bypass passage 22 by the second on-off valve 23, and fully closes the first expansion valve 14.
  • the refrigerant is prevented from flowing into the heat exchanger 15 and the second expansion valve 19 is fully closed to prevent the refrigerant from flowing into the evaporator 20 .
  • the controller 40 causes the refrigerant discharged from the compressor 11 to flow in the order of the indoor condenser 12, the third expansion valve 27, and the chiller 28 to the compressor 11, as indicated by the black arrows in FIG. Establish a return cooling circulation path.
  • the indoor condenser 12 radiates the heat of the high-pressure refrigerant discharged from the compressor 11 to the air, and the chiller 28 absorbs heat from the battery. This makes it possible to heat the passenger compartment and cool the battery.
  • the same dryness increase control as in the first embodiment is performed.
  • the same dryness increasing control as in the first embodiment is performed.
  • the dryness of the refrigerant at the inlet of the outdoor heat exchanger 15 is increased, and the dryness of the refrigerant flowing into the outdoor heat exchanger 15 is increased. Therefore, the liquid refrigerant inside the outdoor heat exchanger 15 is reduced. As a result, it is possible to prevent a shortage of the refrigerant circulating in the refrigerant circulation path in the battery cooling/heating mode.
  • the outlet side of the outdoor heat exchanger 15 is connected to the low-pressure refrigerant circuit, so the refrigerant inside the outdoor heat exchanger 15 is actively discharged, and the inside of the outdoor heat exchanger 15 Liquid refrigerant is further reduced.
  • the shortage of the refrigerant circulating in the refrigerant circulation path in the battery cooling/heating mode can be further suppressed.
  • the second expansion valve 19 and the indoor evaporator 20 are arranged upstream in series with respect to the first expansion valve 14 and the outdoor heat exchanger 15 and in parallel with the third expansion valve 27 and the chiller 28 in the refrigerant flow. are placed in
  • An outlet-side bypass passage 29 is connected to the refrigerant outlet side of the indoor evaporator 20 .
  • the exit-side bypass passage 29 is a refrigerant passage that guides the refrigerant flowing out of the indoor evaporator 20 to the suction side of the compressor 11 by bypassing the first expansion valve 14 and the outdoor heat exchanger 15 .
  • a bypass opening/closing valve 60 is arranged in the outlet-side bypass passage 29 .
  • the bypass opening/closing valve 60 is an electromagnetic valve that opens and closes the outlet side bypass passage 29 .
  • the bypass on-off valve 60 is a refrigerant route switching unit that switches the refrigerant route. The operation of bypass opening/closing valve 60 is controlled by a control signal output from control device 40 . By opening the bypass on-off valve 60 by the controller 40 , the refrigerant flowing out of the indoor evaporator 20 bypasses the outdoor heat exchanger 15 and is sucked into the compressor 11 .
  • the refrigeration cycle device 10 can execute a heating mode and a waste heat recovery mode.
  • the control device 40 shuts off the outlet-side bypass passage 29 by the bypass opening/closing valve 60 and prevents the refrigerant from flowing into the chiller 28 by setting the third expansion valve 27 to a fully closed state.
  • the controller 40 causes the refrigerant discharged from the compressor 11 to flow through the indoor condenser 12, the second expansion valve 19, the indoor evaporator 20, and the first expansion valve 14, as indicated by the white arrows in FIG. , the outdoor heat exchanger 15 and return to the compressor 11 .
  • the outdoor heat exchanger 15 functions as an evaporator
  • the indoor evaporator 20 functions as a condenser
  • the air heated by the indoor evaporator 20 can be blown into the vehicle interior. . This makes it possible to heat the vehicle interior.
  • the control device 40 prevents the refrigerant from flowing into the indoor evaporator 20 and the outdoor heat exchanger 15 by fully closing the second expansion valve 19 .
  • the controller 40 causes the refrigerant discharged from the compressor 11 to flow in the order of the indoor condenser 12, the third expansion valve 27, and the chiller 28 to the compressor 11, as indicated by the black arrows in FIG. Establish a return refrigerant circulation path.
  • the refrigerant is prevented from flowing into the indoor evaporator 20, and the chiller 28 can absorb heat from the battery. Thereby, waste heat recovery from the battery can be realized.
  • the same dryness increase control as in the first embodiment is performed. That is, when switching from the operation mode in which the indoor evaporator 20 functions as a condenser to the operation mode in which the refrigerant does not flow into the indoor evaporator 20, dryness increase control is performed.
  • the dryness of the refrigerant at the inlet of the indoor evaporator 20 is increased, and the dryness of the refrigerant flowing into the indoor evaporator 20 is increased. Therefore, the liquid refrigerant inside the indoor evaporator 20 is reduced. Thereby, it is possible to suppress the shortage of the refrigerant circulating in the refrigerant circulation path in the waste heat recovery mode.
  • the outlet side of the indoor evaporator 20 is connected to the low-pressure refrigerant circuit (specifically, the outlet side bypass passage 29), so the refrigerant inside the indoor evaporator 20 is actively discharged. , the liquid refrigerant inside the indoor evaporator 20 is further reduced. As a result, the shortage of the refrigerant circulating in the refrigerant circulation path in the waste heat recovery mode can be further suppressed.
  • FIG. 10 shows a refrigeration cycle apparatus 10 of this embodiment.
  • the outlet side of the indoor condenser 12 is connected to the inlet side of a first three-way joint 61a having three inlets and outlets communicating with each other.
  • a three-way joint one formed by joining a plurality of pipes or one formed by providing a plurality of refrigerant passages in a metal block or a resin block can be adopted.
  • the refrigeration cycle apparatus 10 includes a second three-way joint 61b, a third three-way joint 61c, a fourth three-way joint 61d, a fifth three-way joint 61e, a sixth three-way joint 61f, a seventh three-way joint 61g, and an eighth three-way joint 61h.
  • the basic configuration of each of the second three-way joint 61b to the eighth three-way joint 61h is the same as that of the first three-way joint 61a.
  • the first three-way joint 61a to the eighth three-way joint 61h use one of the three inflow ports as the inflow port, and when two of the three inflow ports are used as the outflow ports, the flow of the refrigerant flowing in from one inflow port is controlled. It functions as a branching branch.
  • the first three-way joint 61a to the eighth three-way joint 61h use two of the three inflow ports as inflow ports, and when one of the three inflow ports is used as an outflow port, the flow of the refrigerant flowing in from the two inflow ports is controlled. It functions as a merging section for merging.
  • the first three-way joint 61a, the third three-way joint 61c, the sixth three-way joint 61f, and the seventh three-way joint 61g are connected so as to function as branch portions.
  • the second three-way joint 61b, the fourth three-way joint 61d, the fifth three-way joint 61e, and the eighth three-way joint 61h are connected so as to function as a confluence.
  • the inlet side of the receiver 63 is connected to one outflow port of the first three-way joint 61a via the first on-off valve 62 and the fifth three-way joint 61e.
  • the inlet side of the first expansion valve 14 is connected to the other outflow port of the first three-way joint 61a via the second on-off valve 64 and the second three-way joint 61b.
  • the first on-off valve 62 is an electromagnetic valve that opens and closes an inlet-side passage 65 a that extends from one outflow port of the first three-way joint 61 a to the inlet of the receiver 63 .
  • the first on-off valve 62 is a refrigerant path switching unit that switches refrigerant paths.
  • the opening/closing operation of the first opening/closing valve 62 is controlled by a control voltage output from the control device 40 .
  • One inflow port of the fifth three-way joint 61e is connected to the outlet side of the first on-off valve 62 in the inlet-side passage 65a.
  • One outflow port of the fifth three-way joint 61e is connected to the inlet side of the receiver 63 in the inlet side passage 65a.
  • the receiver 63 is a liquid reservoir having a gas-liquid separation function.
  • the receiver 63 separates the gas-liquid refrigerant that has flowed out of the heat exchange section that functions as a condenser that condenses the refrigerant in the refrigeration cycle device 10 .
  • the receiver 63 causes part of the separated liquid-phase refrigerant to flow downstream, and stores the remaining liquid-phase refrigerant as surplus refrigerant in the cycle.
  • the second on-off valve 64 is an electromagnetic valve that opens and closes the outside air passage 65b from the other outflow port of the first three-way joint 61a to one inflow port of the second three-way joint 61b.
  • the second on-off valve 64 is a refrigerant path switching unit that switches refrigerant paths.
  • the basic configuration of the second on-off valve 64 is similar to that of the first on-off valve 62 .
  • the opening/closing operation of the second opening/closing valve 64 is also controlled by the control voltage output from the control device 40 .
  • the refrigerant outlet side of the receiver 63 is connected to the other inlet of the second three-way joint 61b.
  • a sixth three-way joint 61f and a first check valve 66a are arranged in an outlet-side passage 65c that connects the refrigerant outlet of the receiver 63 and the other inlet of the second three-way joint 61b.
  • the inlet of the sixth three-way joint 61f is connected to the refrigerant outlet side of the receiver 63 via the outlet side passage 65c.
  • One outflow port of the sixth three-way joint 61f is connected to the other inflow port of the second three-way joint 61b via an outlet-side passage 65c and a first check valve 66a.
  • the inlet side of the seventh three-way joint 61g is connected to the other outlet of the sixth three-way joint 61f.
  • the refrigerant inlet side of the outdoor heat exchanger 15 is connected via the first expansion valve 14 to the outlet of the second three-way joint 61b.
  • the refrigerant outlet of the outdoor heat exchanger 15 is connected to the inlet side of the third three-way joint 61c.
  • the third on-off valve 67 is an electromagnetic valve that opens and closes the suction side passage 65d from one outflow port of the third three-way joint 61c to one inflow port of the fourth three-way joint 61d.
  • the third on-off valve 67 is a refrigerant path switching unit that switches refrigerant paths. The opening/closing operation of the third opening/closing valve 67 is controlled by a control voltage output from the control device 40 .
  • the inlet side of the compressor 11 is connected to the outflow port of the fourth three-way joint 61d.
  • the other outflow port of the third three-way joint 61c is connected to the other inflow port side of the fifth three-way joint 61e via a second check valve 66b.
  • the second check valve 66b is arranged in the refrigerant passage from the other outflow port of the third three-way joint 61c to the other inflow port of the fifth three-way joint 61e.
  • the second check valve 66b allows the refrigerant to flow from the refrigerant outlet side of the outdoor heat exchanger 15 to the inlet side of the receiver 63 via the third three-way joint 61c.
  • the refrigerant is prohibited from flowing to the refrigerant outlet side of the .
  • the third on-off valve 67 can adjust the flow rate of refrigerant flowing out of the outdoor heat exchanger 15 into the receiver 63 and the flow rate of refrigerant flowing into the compressor 11 as it is.
  • the inlet side of the seventh three-way joint 61g is connected to the other outlet of the sixth three-way joint 61f arranged in the outlet-side passage 65c.
  • One outflow port of the sixth three-way joint 61f is connected to the other inflow port of the second three-way joint 61b via a first check valve 66a.
  • the first check valve 66a allows the refrigerant to flow from the refrigerant outlet side of the receiver 63 to the first expansion valve 14, and prohibits the refrigerant to flow from the second three-way joint 61b side to the receiver 63.
  • the inlet side of the second expansion valve 19 is connected to one outlet of the seventh three-way joint 61g.
  • the inlet side of the third expansion valve 27 is connected to the other outflow port of the seventh three-way joint 61g.
  • the refrigerant inlet side of the indoor evaporator 20 is connected to the outlet of the second expansion valve 19 .
  • One inlet of the eighth three-way joint 61h is connected to the refrigerant outlet of the indoor evaporator 20 via the third check valve 66c.
  • the third check valve 66c allows the refrigerant to flow from the refrigerant outlet side of the indoor evaporator 20 to the eighth three-way joint 61h, and prohibits the refrigerant to flow from the eighth three-way joint 61h side to the indoor evaporator 20.
  • the outlet of the third expansion valve 27 is connected to the inlet side of the refrigerant passage 24 a of the chiller 28 .
  • the refrigerant outlet side of the chiller 28 is connected to the other inlet port of the eighth three-way joint 61h.
  • the suction port side of the compressor 11 is connected to the outflow port of the eighth three-way joint 61h via the fourth three-way joint 61d.
  • the refrigerant circuit can be switched by opening and closing the refrigerant passage with the first on-off valve 62, the second on-off valve 64, and the third on-off valve 67.
  • the refrigeration cycle device 10 can execute a cooling/dehumidifying heating mode, a battery cooling mode, a dehumidifying heating mode, and a heating battery cooling mode by switching the refrigerant circuit.
  • the control device 40 blocks the inlet side passage 65a by the first on/off valve 62, opens the second on/off valve 64 to open the outside air side passage 65b, and fully opens the first expansion valve 14. , and the third expansion valve 27 is fully closed to prevent the refrigerant from flowing into the chiller 28 .
  • the controller 40 causes the refrigerant discharged from the compressor 11 to flow through the indoor condenser 12, the first expansion valve 14, the outdoor heat exchanger 15, and the second non-return valve, as indicated by the white arrows in FIG.
  • a refrigerant circulation path is established in which the refrigerant flows through the valve 66 b , the receiver 63 , the second expansion valve 19 and the indoor evaporator 20 in this order and returns to the compressor 11 .
  • the outdoor heat exchanger 15 functions as a condenser, and the air cooled and dehumidified by the indoor evaporator 20 can be blown out into the passenger compartment. Thereby, cooling or dehumidification/heating of the passenger compartment can be realized.
  • the control device 40 blocks the inlet side passage 65a by the first on-off valve 62, opens the second on-off valve 64 to open the outside air side passage 65b, fully opens the first expansion valve 14, The second expansion valve 19 is fully closed to prevent the refrigerant from flowing into the indoor evaporator 20 .
  • the controller 40 causes the refrigerant discharged from the compressor 11 to flow through the indoor condenser 12, the first expansion valve 14, the outdoor heat exchanger 15, and the second non-return valve, as indicated by black arrows in FIG.
  • a refrigerant circulation path is established in which the refrigerant flows through the valve 66 b , the receiver 63 , the third expansion valve 27 and the chiller 28 in this order and returns to the compressor 11 .
  • the control device 40 stops the blower 32.
  • the refrigerant that has flowed into the indoor condenser 12 flows out of the indoor condenser 12 without substantially exchanging heat with air.
  • the outdoor heat exchanger 15 functions as a condenser
  • the chiller 28 functions as an evaporator.
  • the control device 40 blocks the inlet side passage 65a by the first on-off valve 62, opens the second on-off valve 64 to open the outside air side passage 65b, fully opens the first expansion valve 14,
  • the third expansion valve 27 is fully closed to prevent the refrigerant from flowing into the chiller 28 .
  • the controller 40 causes the refrigerant discharged from the compressor 11 to flow through the indoor condenser 12, the first expansion valve 14, the outdoor heat exchanger 15, and the second non-return valve, as indicated by the white arrows in FIG.
  • a refrigerant circulation path is established in which the refrigerant flows through the valve 66 b , the receiver 63 , the second expansion valve 19 and the indoor evaporator 20 in this order and returns to the compressor 11 .
  • the outdoor heat exchanger 15 functions as a condenser
  • the chiller 28 functions as an evaporator.
  • the control device 40 opens the inlet side passage 65a by opening the first on-off valve 62, blocks the outside air side passage 65b by the second on-off valve 64, fully opens the first expansion valve 14,
  • the third expansion valve 27 is fully closed to prevent the refrigerant from flowing into the chiller 28 .
  • the controller 40 causes the refrigerant discharged from the compressor 11 to pass through the indoor condenser 12, the receiver 63, the second expansion valve 19, and the indoor evaporator 20 in this order, as indicated by the white horizontal arrows in FIG. Establishes a refrigerant circulation path that flows back to the compressor 11 .
  • the refrigerant is prevented from flowing into the outdoor heat exchanger 15, and the air cooled and dehumidified by the indoor evaporator 20 can be blown out into the passenger compartment.
  • dehumidification and heating of the passenger compartment can be achieved.
  • the control device 40 opens the inlet side passage 65a by opening the first on-off valve 62, shuts off the outside air side passage 65b by the second on-off valve 64, and fully opens the first expansion valve 14. , the second expansion valve 19 is fully closed to prevent the refrigerant from flowing into the indoor evaporator 20 .
  • the control device 40 causes the refrigerant discharged from the compressor 11 to flow through the indoor condenser 12, the receiver 63, the third expansion valve 27, and the chiller 28 in this order, as indicated by the hatched white arrows in FIG. A refrigerant circulation path returning to the compressor 11 is established.
  • the refrigerant is prevented from flowing into the outdoor heat exchanger 15, and the air cooled and dehumidified by the indoor evaporator 20 can be blown out into the vehicle compartment. As a result, dehumidification and heating of the passenger compartment can be achieved.
  • control device 40 When switching from the cooling/dehumidifying heating mode or the battery cooling mode to the dehumidifying heating mode or the heating battery cooling mode, the control device 40 performs the same dryness increasing control as in the above embodiment.
  • the dryness of the refrigerant at the inlet of the outdoor heat exchanger 15 is increased, and the dryness of the refrigerant flowing into the outdoor heat exchanger 15 is increased. Therefore, the liquid refrigerant inside the outdoor heat exchanger 15 is reduced. As a result, it is possible to suppress the shortage of the refrigerant circulating in the refrigerant circulation path in the dehumidifying heating mode and the heating battery cooling mode.
  • the outlet side of the outdoor heat exchanger 15 is connected to the low-pressure refrigerant circuit (specifically, the suction side passage 65d), so the refrigerant inside the outdoor heat exchanger 15 is actively The liquid refrigerant inside the outdoor heat exchanger 15 is further reduced. As a result, it is possible to suppress the shortage of the refrigerant circulating in the refrigerant circulation path in the dehumidifying heating mode and the heating battery cooling mode.
  • the refrigeration cycle device 10 includes the indoor condenser 12 that exchanges heat between the high-pressure refrigerant discharged from the compressor 11 and the air blown into the vehicle interior.
  • a condenser that exchanges heat between the high-pressure refrigerant discharged from the machine 11 and the cooling water in the high-temperature cooling water circuit and air, and a heater core that exchanges heat between the cooling water heated by the condenser and the air blown into the passenger compartment. may be provided.
  • the refrigeration cycle device 10 includes the chiller 28 that evaporates the refrigerant with the heat of the battery.
  • the battery may be cooled with cooled cooling water.
  • the operation mode of the vehicle air conditioner when the air conditioner switch is off, the operation mode of the vehicle air conditioner is switched to the heating mode, and when the air conditioner switch is on, the operation mode is switched to the cooling mode or the dehumidifying heating mode.
  • an operation mode setting switch for setting each operation mode may be provided on the operation panel, and the heating mode, cooling mode, and dehumidifying heating mode may be switched according to the operation signal of the operation mode setting switch.
  • the various on-off valves 17, 23, 60, 62, 64, and 67 of the above embodiments may be three-way valves provided at branch points of the refrigerant passage.
  • the three-way valve is an electric three-way flow control valve that has one inlet and two outlets and can adjust the passage area ratio of the two outlets. The operation of the three-way valve is controlled by control signals output from the controller 40 .
  • the refrigeration cycle device 10 of the above embodiment is used for vehicle air conditioning and battery cooling
  • the application target of the refrigeration cycle device 10 is not limited to this.
  • the cooling water cooled by the refrigeration cycle device 10 may be used to cool various equipment to be cooled such as an inverter and a running motor.
  • the refrigeration cycle device 10 may be applied to a stationary air conditioner, a freezer/refrigerator, or the like.
  • the dryness increase control is a control to set the throttle opening degree of the first expansion valve to an opening degree that makes the dryness of the refrigerant in the second condenser equal to or higher than the lower limit dryness (Xmin),
  • the lower limit dryness is a dryness at which the amount of the refrigerant stored in the second condenser is equal to or lower than the upper limit storage amount (Rmax), 5.
  • the refrigeration cycle device according to item 4, wherein the upper limit storage amount is a refrigerant amount that is determined so that the refrigerant does not run short in the second circulation path.
  • the control unit performs the dryness increase control until the dryness of the refrigerant in the second condenser becomes equal to or higher than the minimum dryness (Xmin),
  • the lower limit dryness is a dryness at which the amount of the refrigerant stored in the second condenser is equal to or lower than the upper limit storage amount (Rmax), 6.
  • the refrigeration cycle apparatus according to any one of items 1, 3, 4, and 5, wherein the upper limit storage amount is a refrigerant amount determined so that the refrigerant does not run short in the second circulation path.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Air-Conditioning For Vehicles (AREA)

Abstract

La présente invention comprend : un compresseur (11) qui comprime et évacue un fluide frigorigène ; un premier condenseur (12) et un second condenseur (15) qui condensent le fluide frigorigène par échange de chaleur ; un évaporateur (20) qui évapore le fluide frigorigène par échange de chaleur ; un premier détendeur (14) qui décomprime et dilate le fluide frigorigène s'écoulant dans le second condenseur ; un second détendeur (19) qui décomprime et dilate le fluide frigorigène s'écoulant dans l'évaporateur ; une unité de commutation de trajet de fluide frigorigène (17, 23) qui commute entre un premier trajet de circulation dans lequel le fluide frigorigène circule dans l'ordre du compresseur, du premier condenseur, du premier détendeur, du second condenseur, du second détendeur, de l'évaporateur et du compresseur, et un second trajet de circulation dans lequel le fluide frigorigène circule dans l'ordre du compresseur, du premier condenseur, du second détendeur, de l'évaporateur et du compresseur ; et une unité de commande (40) qui effectue une commande d'augmentation de siccité pour augmenter la siccité du fluide frigorigène dans le second condenseur lors de la commutation du premier trajet de circulation au second trajet de circulation.
PCT/JP2023/004540 2022-03-04 2023-02-10 Dispositif à cycle de réfrigération WO2023166951A1 (fr)

Applications Claiming Priority (2)

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JP2022-033458 2022-03-04
JP2022033458 2022-03-04

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WO2023166951A1 true WO2023166951A1 (fr) 2023-09-07

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2018077020A (ja) * 2016-11-11 2018-05-17 株式会社デンソー 冷凍サイクル装置
WO2022024721A1 (fr) * 2020-07-27 2022-02-03 株式会社デンソー Dispositif à cycle de réfrigération
JP2022033453A (ja) * 2020-08-17 2022-03-02 株式会社デンソー 冷凍サイクル装置

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2018077020A (ja) * 2016-11-11 2018-05-17 株式会社デンソー 冷凍サイクル装置
WO2022024721A1 (fr) * 2020-07-27 2022-02-03 株式会社デンソー Dispositif à cycle de réfrigération
JP2022033453A (ja) * 2020-08-17 2022-03-02 株式会社デンソー 冷凍サイクル装置

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