WO2018042859A1

WO2018042859A1 - Refrigeration cycle device

Info

Publication number: WO2018042859A1
Application number: PCT/JP2017/023912
Authority: WO
Inventors: 慧伍佐藤; 加藤　吉毅; 竹内　雅之; 橋村　信幸; 功嗣三浦; 憲彦榎本; 賢吾杉村; アリエルマラシガン
Original assignee: 株式会社デンソー
Priority date: 2016-08-29
Filing date: 2017-06-29
Publication date: 2018-03-08
Also published as: JP2018035951A

Abstract

A refrigeration cycle device comprises: a compressor (11); a radiator (14) that dissipates heat from refrigerant delivered from the compressor (11); a pressure reducing unit (15) that reduces the pressure of the refrigerant for which the heat has been dissipated by the radiator (14); an evaporator (17) that cools a heating medium by exchanging heat between the heating medium and the refrigerant for which the pressure has been reduced by the pressure reducing unit (15); a first machine to be cooled (32) and a second machine to be cooled (27) that are cooled by using the cold of the refrigerant for which the pressure has been reduced by the pressure reducing unit (15); a heating medium circuit (30) that circulates the heating medium cooled by the evaporator (17) to only the first machine to be cooled (32) of the first machine to be cooled (32) and the second machine to be cooled (27); and a flow rate adjusting unit (31) that adjusts the flow rate of the heating medium flowing to the first machine to be cooled (32).

Description

Refrigeration cycle equipment

Cross-reference of related applications

This application is based on Japanese Patent Application No. 2016-166594 filed on Aug. 29, 2016, the disclosure of which is incorporated herein by reference.

This disclosure relates to a refrigeration cycle apparatus that cools a plurality of devices to be cooled.

Conventionally, Patent Document 1 describes a refrigeration cycle apparatus in which two evaporators are connected in parallel with each other in a refrigerant flow. This prior art includes two sets of solenoid valves, an expansion valve, and an evaporator connected in parallel to each other. Each set of solenoid valves, expansion valves and evaporators are arranged in series with each other in the refrigerant flow, and each set of solenoid valves and expansion valves is controlled to distribute the cold heat of the refrigerant to the two evaporators.

In this conventional technology, one of the two evaporators cools the conditioned air by exchanging heat between the conditioned air and the refrigerant. In the other evaporator of the two evaporators, the air blown to the battery is heat-exchanged with the refrigerant to cool the air blown to the battery.

Conventionally, Patent Document 2 describes a refrigeration cycle apparatus that cools cooling water by exchanging heat between refrigerant and cooling water in an evaporator. In this prior art, the temperature adjustment object apparatus is cooled by circulating the cooling water cooled by the evaporator to the temperature adjustment object apparatus. When a plurality of temperature adjustment target devices are provided, the plurality of temperature adjustment target devices are cooled by circulating the cooling water cooled by the evaporator through the plurality of temperature adjustment target devices.

JP 2003-279180 A JP 2014-218237 A

In the prior art disclosed in Patent Document 1, since the two sets of expansion valve and evaporator are connected in parallel to each other, the refrigerant circuit becomes complicated. In addition, it is difficult to properly control the temperature of the two evaporators by appropriately distributing the refrigerant to the two sets of expansion valves and evaporators. Moreover, in the evaporator with the smaller refrigerant flow rate of the two evaporators, the refrigerant and the refrigerating machine oil tend to stay.

In the prior art of the above-mentioned Patent Document 2, since the same cooling water is circulated through a plurality of temperature adjustment target devices, if the requirements for a plurality of temperature adjustment target devices, for example, temperature zones and insulation requirements are different from each other, It is difficult to satisfy these requirements simultaneously.

In view of the above points, the present disclosure simplifies the configuration of a refrigerant circuit, facilitates temperature control, suppresses retention of refrigerant and refrigerating machine oil, and easily satisfies the requirements of a plurality of cooling target devices. With the goal.

A refrigeration cycle apparatus according to an example of the present disclosure includes a compressor that sucks in, compresses and discharges a refrigerant, a radiator that dissipates heat from the refrigerant discharged from the compressor, and a decompression unit that depressurizes the refrigerant dissipated by the radiator. An evaporator that cools the heat medium by exchanging heat between the refrigerant depressurized by the depressurization unit and the heat medium, a first cooling target device that is cooled by using the cold heat of the refrigerant depressurized by the depressurization unit, and a second A cooling target device, a heat medium circuit that circulates the heat medium cooled by the evaporator only to the first cooling target device among the first cooling target device and the second cooling target device, and heat flowing into the first cooling target device A flow rate adjusting unit for adjusting the flow rate of the medium.

According to this, since the temperature of the first cooling target device among the first cooling target device and the second cooling target device can be controlled by the flow rate adjusting unit, the prior art of the above-described Patent Document 1 that distributes the refrigerant to two evaporators. In comparison with the above, the configuration of the refrigerant circuit can be simplified, the temperature control can be facilitated, and the retention of refrigerant and refrigerating machine oil can be suppressed.

In addition, since the heat medium of the heat medium circuit circulates only to the first cooling target device among the first cooling target device and the second cooling target device and does not circulate to the second cooling target device, the first cooling target device and the first cooling target device 2 It becomes easy to satisfy the requirements of the equipment to be cooled.

It is a whole lineblock diagram of the refrigerating cycle device in a 1st embodiment. It is a Mollier diagram which shows the state of the refrigerant | coolant at the time of the air_conditioning | cooling mode of the refrigerating-cycle apparatus in 1st Embodiment. It is a Mollier diagram which shows the state of the refrigerant | coolant at the time of the heating mode of the refrigeration cycle apparatus in 1st Embodiment. It is a whole block diagram of the refrigerating-cycle apparatus in 2nd Embodiment. It is a whole block diagram of the refrigerating-cycle apparatus in 3rd Embodiment.

Hereinafter, embodiments will be described with reference to the drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings.

(First embodiment)
A refrigeration cycle apparatus 10 shown in FIG. 1 is a vehicular refrigeration cycle apparatus used for adjusting a vehicle interior space to an appropriate temperature. In the present embodiment, the refrigeration cycle apparatus 10 is applied to a hybrid vehicle that obtains driving force for vehicle travel from an engine (in other words, an internal combustion engine) and a travel electric motor.

The hybrid vehicle of the present embodiment is configured as a plug-in hybrid vehicle capable of charging power supplied from an external power source (in other words, commercial power source) when the vehicle is stopped to a battery (in other words, an in-vehicle battery) mounted on the vehicle. Has been. As the battery, for example, a lithium ion battery can be used.

The driving force output from the engine is used not only for driving the vehicle but also for operating the generator. And the electric power generated by the generator and the electric power supplied from the external power source can be stored in the battery, and the electric power stored in the battery constitutes the refrigeration cycle apparatus 10 as well as the electric motor for traveling. It is supplied to various in-vehicle devices such as electric components.

The refrigeration cycle apparatus 10 includes a compressor 11, a condenser 12, a first expansion valve 13, an outdoor heat exchanger 14, a second expansion valve 15, a battery evaporator 16, and a cooler core evaporator 17. It is. In the refrigeration cycle apparatus 10 of the present embodiment, a chlorofluorocarbon refrigerant is used as the refrigerant, and a subcritical refrigeration cycle in which the high-pressure side refrigerant pressure does not exceed the refrigerant critical pressure is configured.

The compressor 11, the condenser 12, the first expansion valve 13, the outdoor heat exchanger 14, the second expansion valve 15, the battery evaporator 16 and the cooler core evaporator 17 are arranged in series with each other in the refrigerant flow. . For example, as shown in FIG. 1, the battery evaporator 16 and the cooler core evaporator 17 are directly connected without any other components. Therefore, the refrigerant that has passed through the pond evaporator 16 flows directly to the cooler core evaporator 17.

The compressor 11 is an electric compressor that is driven by electric power supplied from a battery, and sucks, compresses and discharges the refrigerant of the refrigeration cycle apparatus 10. The compressor 11 may be a variable capacity compressor driven by a belt.

The condenser 12 is a condenser that condenses the high-pressure side refrigerant by exchanging heat between the high-pressure side refrigerant discharged from the compressor 11 and the cooling water of the high-temperature cooling water circuit 20.

The high-temperature coolant circuit 20 is a heat medium circuit in which coolant as a heat medium circulates. In this embodiment, a liquid containing at least ethylene glycol, dimethylpolysiloxane or nanofluid, or an antifreeze liquid is used as the cooling water of the high-temperature cooling water circuit 20.

In the high temperature cooling water circuit 20, a condenser 12, a high temperature side pump 21 and a heater core 22 are arranged. The high temperature side pump 21 is a heat medium pump that sucks and discharges cooling water. The high temperature side pump 21 is an electric pump. The high temperature side pump 21 is a flow rate adjusting unit that adjusts the flow rate of the cooling water circulating in the high temperature cooling water circuit 20.

The heater core 22 is an air heating heat exchanger that heats the air blown into the vehicle interior by exchanging heat between the cooling water of the high-temperature coolant circuit 20 and the air blown into the vehicle interior. In the heater core 22, the cooling water radiates heat to the air blown into the vehicle interior due to a change in sensible heat. That is, in the heater core 22, even if the cooling water dissipates heat to the air blown into the passenger compartment, the cooling water remains in a liquid phase and does not change phase.

The first expansion valve 13 is a first decompression unit that decompresses and expands the liquid refrigerant that has flowed out of the condenser 12. The first expansion valve 13 is an electric variable throttle mechanism, and includes a valve body and an electric actuator. The valve body is configured to be able to change the passage opening (in other words, the throttle opening) of the refrigerant passage. The electric actuator has a stepping motor that changes the throttle opening of the valve body.

The first expansion valve 13 is composed of a variable throttle mechanism with a fully open function that fully opens the refrigerant passage when the throttle opening is fully opened. That is, the first expansion valve 13 can prevent the refrigerant from depressurizing by fully opening the refrigerant passage. The operation of the first expansion valve 13 is controlled by a control signal output from the control device 40.

The outdoor heat exchanger 14 is a refrigerant outdoor air heat exchanger that exchanges heat between the refrigerant flowing out of the first expansion valve 13 and the outside air. Outside air is blown to the outdoor heat exchanger 14 by an outdoor blower 18.

The outdoor blower 18 is a blower that blows outside air toward the outdoor heat exchanger 14. The outdoor blower 18 is an electric blower that drives a fan with an electric motor. The outdoor heat exchanger 14 and the outdoor blower 18 are disposed in the foremost part of the vehicle. Therefore, traveling wind can be applied to the outdoor heat exchanger 14 when the vehicle is traveling.

When the temperature of the refrigerant flowing through the outdoor heat exchanger 14 is lower than the temperature of the outside air, the outdoor heat exchanger 14 functions as a heat absorber that causes the refrigerant to absorb the heat of the outside air. When the temperature of the refrigerant flowing through the outdoor heat exchanger 14 is higher than the temperature of the outside air, the outdoor heat exchanger 14 functions as a radiator that radiates the heat of the refrigerant to the outside air.

The outdoor heat exchanger 14 has a heat exchange part 141, a liquid storage part 142, and a supercooling part 143. The heat exchanging unit 141 of the outdoor heat exchanger 14 exchanges heat between the refrigerant flowing out of the first expansion valve 13 and the outside air. The liquid storage part 142 of the outdoor heat exchanger 14 is a refrigerant storage part that separates the gas-liquid refrigerant flowing out from the heat exchange part 141 of the outdoor heat exchanger 14 and stores excess refrigerant. The supercooling unit 143 of the outdoor heat exchanger 14 supercools the liquid phase refrigerant by exchanging heat between the liquid refrigerant flowing out of the liquid storage unit 142 of the outdoor heat exchanger 14 and the outside air.

The supercooling bypass pipe 19 is connected to the liquid storage part 142 of the outdoor heat exchanger 14. The supercooling bypass pipe 19 is a supercooling section bypass section in which the refrigerant that has flowed through the liquid storage section 142 of the outdoor heat exchanger 14 flows bypassing the supercooling section 143.

The supercooling bypass pipe 19 is provided with a supercooling bypass opening / closing valve 19a. The supercooling bypass opening / closing valve 19 a is a supercooling bypass opening adjustment unit that adjusts the flow opening of the supercooling bypass pipe 19. The supercooling bypass opening / closing valve 19 a is an electromagnetic valve and is controlled by the control device 40.

The second expansion valve 15 is a second decompression unit that decompresses and expands the liquid-phase refrigerant that has flowed out of the outdoor heat exchanger 14. The second expansion valve 15 is an electric variable throttle mechanism, and includes a valve body and an electric actuator. The valve body is configured to be able to change the passage opening (in other words, the throttle opening) of the refrigerant passage. The electric actuator has a stepping motor that changes the throttle opening of the valve body.

The second expansion valve 15 is composed of a variable throttle mechanism with a fully open function that fully opens the refrigerant passage when the throttle opening is fully opened. That is, the second expansion valve 15 can prevent the refrigerant from depressurizing by fully opening the refrigerant passage. The operation of the second expansion valve 15 is controlled by a control signal output from the control device 40.

The cooling mode and the heating mode are switched by changing the throttle openings of the first expansion valve 13 and the second expansion valve 15. The cooling mode is a heat dissipation mode in which the refrigerant is radiated by the outdoor heat exchanger 14. The heating mode is an endothermic mode in which the refrigerant is absorbed by the outdoor heat exchanger 14. The first expansion valve 13 and the second expansion valve 15 are operation mode switching units that switch between a cooling mode and a heating mode.

The battery evaporator 16 is an evaporator that evaporates the low-pressure refrigerant by exchanging heat between the low-pressure refrigerant flowing out of the second expansion valve 15 and the insulating oil of the insulating oil circuit 25. The battery evaporator 16 is disposed upstream of the cooler core evaporator 17 in the refrigerant flow. The low-pressure refrigerant that has flowed out of the battery evaporator 16 flows into the cooler core evaporator 17.

The insulating oil in the insulating oil circuit 25 is a fluid as a heat medium. The insulating oil of the insulating oil circuit 25 is an insulating heat medium having insulating properties. In the insulating oil circuit 25, a battery evaporator 16, an insulating oil pump 26, and a battery 27 are arranged.

The insulating oil pump 26 is a heat medium pump that sucks and discharges insulating oil. The insulating oil pump 26 is an electric pump. The insulating oil pump 26 is an insulating oil flow rate adjusting unit that adjusts the flow rate of the insulating oil circulating in the insulating oil circuit 25.

The battery 27 is an in-vehicle device mounted on the vehicle. The battery 27 is a heat-generating device that generates heat when activated. The battery 27 has an insulating oil passage through which insulating oil flows, and is a device to be cooled that is cooled by the insulating oil. The required cooling temperature of the battery 27 is, for example, about 10 ° C. to 40 ° C.

In the battery 27, the insulating oil absorbs heat by sensible heat change. That is, in the battery 27, even if the insulating oil absorbs heat, the insulating oil remains in a liquid phase and does not change in phase. Since the insulating oil has an insulating property, the insulating property inside the battery 27 can be maintained even if the insulating oil is passed through the battery 27 in order to cool the battery 27.

The cooler core evaporator 17 is disposed downstream of the battery evaporator 16 in the refrigerant flow. The cooler core evaporator 17 is an evaporator that evaporates the low-pressure refrigerant by exchanging heat between the low-pressure refrigerant flowing out of the battery evaporator 16 and the cooling water of the low-temperature cooling water circuit 30. The cooler core evaporator 17 is a first evaporator, and the battery evaporator 16 is a second evaporator. The gas-phase refrigerant evaporated in the cooler core evaporator 17 is sucked into the compressor 11 and compressed.

The low-temperature cooling water circuit 30 is a heat medium circuit in which cooling water as a heat medium circulates. The cooling water of the low-temperature cooling water circuit 30 is a first heat medium, and the insulating oil of the insulating oil circuit 25 is a second heat medium. The low-temperature coolant circuit 30 is a first heat medium circuit, and the insulating oil circuit 25 is a second heat medium circuit.

In the present embodiment, a liquid containing at least ethylene glycol, dimethylpolysiloxane or nanofluid, or an antifreeze liquid is used as the cooling water of the low-temperature cooling water circuit 30.

In the low-temperature cooling water circuit 30, a cooler core evaporator 17, a low temperature side pump 31, and a cooler core 32 are arranged.

The low temperature side pump 31 is a heat medium pump that sucks and discharges cooling water. The low temperature side pump 31 is an electric pump. The low temperature side pump 31 is a flow rate adjusting unit that adjusts the flow rate of the cooling water circulating in the low temperature cooling water circuit 30. The low temperature side pump 31 is a first flow rate adjusting unit, and the insulating oil pump 26 is a second flow rate adjusting unit.

The cooler core 32 is an air cooling heat exchanger that cools the air blown into the vehicle interior by exchanging heat between the cooling water of the low-temperature cooling water circuit 30 and the air blown into the vehicle interior. In the cooler core 32, the cooling water absorbs heat from the air blown into the vehicle interior due to a change in sensible heat. That is, in the cooler core 32, even if the cooling water absorbs heat from the air blown into the passenger compartment, the cooling water remains in a liquid phase and does not change phase. The cooler core 32 is a device to be cooled that is cooled by cooling water. The cooler core 32 is a first cooling target device, and the battery 27 is a second cooling target device.

The required cooling temperature of the cooler core 32 is, for example, about 0 ° C. That is, the required cooling temperature is different between the battery 27 and the cooler core 32 which are the devices to be cooled. Specifically, the battery 27 has a higher required cooling temperature than the cooler core 32, and the cooler core 32 has a lower required cooling temperature than the battery 27.

The cooler core 32 and the heater core 22 are accommodated in a casing (hereinafter referred to as an air conditioning casing) of an indoor air conditioning unit (not shown). The air conditioning casing is an air passage forming member that forms an air passage.

The heater core 22 is disposed on the air flow downstream side of the cooler core 32 in the air passage in the air conditioning casing. The air conditioning casing is disposed in the vehicle interior space.

In the air conditioning casing, an inside / outside air switching box (not shown) and an indoor fan (not shown) are arranged. The inside / outside air switching box is an inside / outside air switching unit that switches between introduction of inside air and outside air into an air passage in the air conditioning casing. The indoor blower sucks and blows the inside air and the outside air introduced into the air passage in the air conditioning casing through the inside / outside air switching box.

An air mix door (not shown) is disposed between the cooler core 32 and the heater core 22 in the air passage in the air conditioning casing. The air mix door adjusts the air volume ratio between the cool air that has passed through the cooler core 32 and the cool air that flows into the heater core 22 and the cool air that bypasses the heater core 22 and flows.

The air mix door is a rotary door that is rotatably supported with respect to the air conditioning casing. By adjusting the opening position of the air mix door, the temperature of the conditioned air blown from the air conditioning casing into the vehicle compartment can be adjusted to a desired temperature. The air mix door is driven by a servo motor. The operation of the servo motor is controlled by the control device 40.

One end of a bypass pipe 35 is connected to the refrigerant outlet side of the outdoor heat exchanger 14 and the refrigerant inlet side of the second expansion valve 15. The bypass pipe 35 is an evaporator bypass section in which the refrigerant flowing out of the outdoor heat exchanger 14 flows by bypassing the second expansion valve 15, the battery evaporator 16, and the cooler core evaporator 17. The other end of the bypass pipe 35 is connected to the refrigerant outlet side of the cooler core evaporator 17 and the refrigerant suction side of the compressor 11.

The bypass pipe 35 is provided with a bypass opening / closing valve 36. The bypass opening / closing valve 36 is a bypass opening adjustment unit that adjusts the opening of the bypass pipe 35. The bypass opening / closing valve 36 is an electromagnetic valve and is controlled by the control device 40.

The control device 40 has a known microcomputer including a CPU, a ROM, a RAM, and the like and peripheral circuits thereof. The control device 40 performs various calculations and processes based on a control program stored in the ROM. Various devices to be controlled are connected to the output side of the control device 40. The control device 40 is a control unit that controls operations of various devices to be controlled.

The control target devices controlled by the control device 40 include the compressor 11, the first expansion valve 13, the second expansion valve 15, the outdoor blower 18, the supercooling bypass on-off valve 19a, the high temperature side pump 21, the insulating oil pump 26, and the low temperature. A side pump 31 and the like.

Software and hardware for controlling the electric motor of the compressor 11 in the control device 40 is a refrigerant discharge capacity control unit. Software and hardware for controlling the first expansion valve 13 in the control device 40 is a first throttle control unit. Software and hardware for controlling the second expansion valve 15 in the control device 40 is a second throttle control unit.

Software and hardware for controlling the outdoor blower 18 in the control device 40 are an outside air blowing capacity control unit. Software and hardware for controlling the supercooling bypass opening / closing valve 19a in the control device 40 is a bypass opening control unit.

The software and hardware for controlling the high temperature side pump 21 in the control device 40 is a high temperature side heat medium flow control unit. Software and hardware for controlling the insulating oil pump 26 in the control device 40 is an insulating heat medium flow control unit. Software and hardware for controlling the low temperature side pump 31 in the control device 40 is a low temperature side heat medium flow control unit.

The input side of the control device 40 is connected to various air conditioning control sensors such as an inside air temperature sensor (not shown), an outside air temperature sensor (not shown), and a solar radiation amount sensor (not shown). The inside air temperature sensor detects the passenger compartment temperature Tr. The outside air temperature sensor detects the outside air temperature Tam. The solar radiation amount sensor detects the solar radiation amount Ts in the passenger compartment.

Various control switches (not shown) are connected to the input side of the control device 40. Various operation switches are provided on an operation panel (not shown) and are operated by a passenger. The operation panel is arranged near the instrument panel at the front of the passenger compartment. Operation signals from various operation switches are input to the control device 40.

The various operation switches are air conditioner switches, temperature setting switches, etc. The air conditioner switch sets whether to cool the air in the indoor air conditioning unit. The temperature setting switch sets a set temperature in the passenger compartment.

Next, the operation in the above configuration will be described. The control device 40 switches the air conditioning mode to either the heating mode or the cooling mode based on the target blowing temperature TAO or the like.

The target blowing temperature TAO is the target temperature of the blowing air blown out into the passenger compartment. The control device 40 calculates the target blowing temperature TAO based on the following mathematical formula.

TAO = Kset × Tset−Kr × Tr−Kam × Tam−Ks × Ts + C
In this equation, Tset is the vehicle interior set temperature set by the temperature setting switch on the operation panel, Tr is the inside air temperature detected by the inside air temperature sensor, Tam is the outside air temperature detected by the outside air temperature sensor, and Ts is the solar radiation amount sensor. Is the amount of solar radiation detected by. Kset, Kr, Kam, Ks are control gains, and C is a correction constant.

Next, the operation in the cooling mode and the heating mode will be described. The cooling mode is a first mode in which the outdoor heat exchanger 14 releases heat from the refrigerant. The heating mode is a second mode in which the outdoor heat exchanger 14 absorbs heat from the refrigerant.

(Cooling mode)
In the cooling mode, the control device 40 sets the first expansion valve 13 to a fully open state and sets the second expansion valve 15 to a throttle state. In the cooling mode, the control device 40 stops the high temperature side pump 21 and drives the low temperature side pump 31.

The control device 40 determines the operating states of the various control devices connected to the control device 40 (control signals output to the various control devices) based on the target blowing temperature TAO, the detection signal of the sensor group, and the like.

With respect to the control signal output to the second expansion valve 15, a target excess value determined in advance so that the degree of supercooling of the refrigerant flowing into the second expansion valve 15 approaches the maximum coefficient of performance (so-called COP) of the cycle. It is determined to approach the degree of cooling.

For the control signal output to the servo motor of the air mix door (not shown), the air mix door closes the air passage of the heater core 22 so that the total flow rate of the blown air that has passed through the cooler core 32 bypasses the heater core 22 and flows. It is determined.

In the refrigeration cycle apparatus 10 in the cooling mode, the state of the refrigerant circulating in the cycle changes as shown in the Mollier diagram of FIG.

That is, the high-pressure refrigerant discharged from the compressor 11 flows into the condenser 12 as indicated by a point a1 in FIG. At this time, since the high temperature side pump 21 is stopped, the cooling water of the high temperature cooling water circuit 20 does not circulate in the condenser 12. Therefore, the refrigerant that has flowed into the condenser 12 flows out of the condenser 12 with almost no heat exchange with the cooling water in the high-temperature cooling water circuit 20.

The refrigerant that has flowed out of the condenser 12 flows into the first expansion valve 13. At this time, since the first expansion valve 13 fully opens the refrigerant passage, the refrigerant flowing out of the condenser 12 flows into the outdoor heat exchanger 14 without being depressurized by the first expansion valve 13.

As shown at points a1 and a2 in FIG. 2, the refrigerant flowing into the outdoor heat exchanger 14 dissipates heat to the outside air blown from the outdoor blower 18 by the outdoor heat exchanger 14.

In the cooling mode, the control device 40 closes the bypass on-off valve 36. Thus, as shown at points a2 and a3 in FIG. 2, the refrigerant flowing out of the outdoor heat exchanger 14 flows into the second expansion valve 15 and is depressurized until it becomes a low-pressure refrigerant at the second expansion valve 15. Inflated. As shown at points a3 and a4 in FIG. 2, the low-pressure refrigerant decompressed by the second expansion valve 15 flows into the battery evaporator 16, and absorbs heat from the insulating oil in the insulating oil circuit 25 to evaporate. Thereby, since the insulating oil of the insulating oil circuit 25 is cooled, the battery 27 is cooled.

2, the low-pressure refrigerant that has flowed out of the battery evaporator 16 flows into the cooler core evaporator 17, absorbs heat from the cooling water in the low-temperature cooling water circuit 30, and evaporates. Thereby, since the cooling water of the low-temperature cooling water circuit 30 is cooled, the air is cooled by the cooler core 32.

2, the refrigerant flowing out of the cooler core evaporator 17 flows to the suction side of the compressor 11 and is compressed again by the compressor 11.

In the outdoor heat exchanger 14, the refrigerant condensed in the heat exchange unit 141 is gas-liquid separated in the liquid storage unit 142, and excess liquid phase refrigerant is stored. In the cooling mode, the control device 40 closes the supercooling bypass opening / closing valve 19a. As a result, the liquid-phase refrigerant flowing out of the liquid storage unit 142 flows through the supercooling unit 143 and is supercooled.

As described above, in the cooling mode, the low-pressure refrigerant absorbs heat from the insulating oil in the insulating oil circuit 25 and the insulating oil in the insulating oil circuit 25 absorbs heat from the battery 27 in the battery evaporator 16. In the cooling mode, the low-pressure refrigerant absorbs heat from the cooling water in the low-temperature cooling water circuit 30 in the cooler core evaporator 17, and the cooling water in the low-temperature cooling water circuit 30 is cooled in the cooler core 32 from the air blown into the vehicle interior. It absorbs heat. Therefore, in the cooling mode, the battery 27 can be cooled and the vehicle interior can be cooled.

In the cooling mode, as shown from point a3 to point a5 in FIG. 2, the refrigerant pressure in the battery evaporator 16 and the cooler core evaporator 17 decreases due to pressure loss. It becomes lower than the refrigerant pressure in the evaporator 16 for use.

Therefore, since the refrigerant temperature in the cooler core evaporator 17 is lower than the refrigerant temperature in the battery evaporator 16, the cooling water temperature in the low-temperature cooling water circuit 30 is lower than the insulating oil temperature in the insulating oil circuit 25. Therefore, the cooler core 32 can be set to a temperature lower than that of the battery 27.

In the cooling mode, the control device 40 adjusts the flow rate of the insulating oil in the insulating oil circuit 25 with the insulating oil pump 26. Thereby, the temperature of the battery 27 can be appropriately adjusted to the required cooling temperature (for example, about 10 to 40 ° C.).

In the cooling mode, the control device 40 adjusts the flow rate of the cooling water in the low temperature cooling water circuit 30 with the low temperature side pump 31. Thereby, the temperature of the air cooled by the cooler core 32 can be appropriately adjusted to the required cooling temperature, for example, about 0 ° C.

(Heating mode)
In the heating mode, the control device 40 brings the first expansion valve 13 into a throttled state and the second expansion valve 15 into a fully opened state. In the heating mode, the control device 40 drives the high temperature side pump 21 and stops the low temperature side pump 31.

The control signal output to the first expansion valve 13 is determined so that the supercooling degree of the refrigerant flowing into the first expansion valve 13 approaches a predetermined target supercooling degree. The target degree of supercooling is determined so that the coefficient of performance of the cycle (so-called COP) approaches the maximum value.

As for a control signal output to a servo motor of an air mix door (not shown), the air mix door fully opens the air passage of the heater core 22 so that the total flow rate of the blown air that has passed through the cooler core 32 passes through the air passage of the heater core 22. To be determined.

In the heating mode, the state of the refrigerant circulating in the cycle changes as shown in the Mollier diagram of FIG.

That is, as indicated by points b1 and b2 in FIG. 3, the high-pressure refrigerant discharged from the compressor 11 flows into the condenser 12 and exchanges heat with the cooling water in the high-temperature cooling water circuit 20 to dissipate heat. Thereby, the cooling water of the high temperature cooling water circuit 20 is heated.

As shown at points b2 and b3 in FIG. 3, the refrigerant flowing out of the condenser 12 flows into the first expansion valve 13 and is depressurized until it becomes a low-pressure refrigerant. As shown at points b3 and b4 in FIG. 3, the low-pressure refrigerant decompressed by the first expansion valve 13 flows into the outdoor heat exchanger 14 and absorbs heat from the outside air blown from the outdoor blower 18. Evaporate.

In the heating mode, the control device 40 opens the bypass opening / closing valve 36. As a result, as shown at points b4 and b1 in FIG. 3, the refrigerant flowing out of the outdoor heat exchanger 14 bypasses the second expansion valve 15, the battery evaporator 16, and the cooler core evaporator 17, thereby compressing the compressor. 11 flows to the suction side and is compressed again by the compressor 11.

In the heating mode, the control device 40 opens the supercooling bypass opening / closing valve 19a. Thereby, since the refrigerant | coolant which flowed out from the liquid storage part 142 of the outdoor heat exchanger 14 bypasses the supercooling part 143, and flows through the supercooling part bypass piping 35, the pressure loss of a refrigerant | coolant can be reduced.

As described above, in the heating mode, the condenser 12 radiates heat from the high-pressure refrigerant to the cooling water of the high-temperature cooling water circuit 20, and the heater core 22 converts the cooling water of the high-temperature cooling water circuit 20 into the air blown into the vehicle interior. Dissipate heat. Thereby, a vehicle interior can be heated.

Thus, in the vehicle air conditioner 1 of the present embodiment, appropriate cooling and heating of the vehicle interior can be performed by changing the throttle opening of the first expansion valve 13 and the second expansion valve 15. As a result, comfortable air conditioning in the passenger compartment can be realized.

The refrigeration cycle apparatus of the present embodiment includes a cooler core 32, a battery 27, a low-temperature cooling water circuit 30, and a low-temperature side pump 31. The cooler core 32 and the battery 27 are cooled using the cold heat of the refrigerant decompressed by the second expansion valve 15. The low-temperature cooling water circuit 30 circulates the cooling water cooled by the cooler core evaporator 17 only to the cooler core 32 of the cooler core 32 and the battery 27. The low temperature side pump 31 adjusts the flow rate of the cooling water flowing into the cooler core 32.

According to this, the cooler core 32 and the battery 27 can be cooled without distributing the refrigerant, and the temperature of the cooler core 32 can be controlled by the low temperature side pump 31. Therefore, compared with the prior art disclosed in Patent Document 1 in which the refrigerant is distributed to the two evaporators, the refrigerant circuit can be simplified, temperature control can be facilitated, and stagnation of the refrigerant and refrigerating machine oil can be suppressed.

In addition, the cooling water of the low-temperature cooling water circuit 30 circulates only to the cooler core 32 of the cooler core 32 and the battery 27 and does not circulate to the battery 27. Therefore, requirements of the cooler core 32 and the battery 27 (for example, required cooling temperature, insulation, etc.) It is easy to satisfy (request).

The refrigeration cycle apparatus of the present embodiment includes an insulating oil circuit 25 and an insulating oil pump 26. The insulating oil circuit 25 circulates the insulating oil cooled by the battery evaporator 16 to the battery 27. The insulating oil pump 26 adjusts the flow rate of the insulating oil flowing into the battery 27. The battery evaporator 16 and the cooler core evaporator 17 are arranged in series with each other in the refrigerant flow.

According to this, the temperature of the battery 27 can be easily adjusted by the insulating oil pump 26 adjusting the flow rate of the insulating oil.

In the present embodiment, the battery evaporator 16 is disposed upstream of the cooler core evaporator 17 in the refrigerant flow. According to this, since the refrigerant pressure in the battery evaporator 16 becomes higher than the refrigerant pressure in the cooler core evaporator 17 due to the pressure loss in the battery evaporator 16 and the cooler core evaporator 17, in the battery evaporator 16 The refrigerant temperature becomes higher than the refrigerant temperature in the cooler core evaporator 17. Therefore, the temperature zone of the battery 27 can be made higher than the temperature zone of the cooler core 32 in accordance with the respective required cooling temperatures of the battery 27 and the cooler core 32.

(Second Embodiment)
In the above embodiment, the battery 27 has an insulating oil passage through which the insulating oil flows, and is cooled by the insulating oil. However, in this embodiment, as shown in FIG. The battery 50 is placed in contact with the battery 50 so as to conduct heat and is cooled by the battery cooler 50.

The battery cooler 50 is an evaporator that evaporates low-pressure refrigerant by causing the low-pressure refrigerant flowing out of the second expansion valve 15 to absorb heat from the battery 27. The battery cooler 50 is disposed upstream of the cooler core evaporator 17 in the refrigerant flow. The battery cooler 50 is directly connected to the cooler core evaporator 17 without any other components. Therefore, the low-pressure refrigerant flowing out from the battery cooler 50 flows into the cooler core evaporator 17.

The battery cooler 50 is a refrigerant circulation device through which the low-pressure refrigerant that has flowed out of the second expansion valve 15 circulates. The battery cooler 50 is a device to be cooled that is cooled by the low-pressure refrigerant that has flowed out of the second expansion valve 15. The battery cooler 50 is a second cooling target device. The battery cooler 50 is an in-vehicle device cooler for cooling the in-vehicle device.

In the battery cooler 50 and the cooler core evaporator 17, the refrigerant pressure decreases due to pressure loss, so the refrigerant pressure in the cooler core evaporator 17 is lower than the refrigerant pressure in the battery cooler 50.

Therefore, since the refrigerant temperature in the cooler core evaporator 17 is lower than the refrigerant temperature in the battery cooler 50, the cooling water temperature in the low-temperature cooling water circuit 30 is lower than the insulating oil temperature in the battery cooler 50. Therefore, the cooler core 32 can be set to a temperature lower than that of the battery 27.

One end of a battery bypass pipe 51 is connected to the refrigerant outlet side of the second expansion valve 15 and the refrigerant inlet side of the battery cooler 50. The other end of the battery bypass pipe 51 is connected to the refrigerant outlet side of the battery cooler 50 and the refrigerant inlet side of the cooler core evaporator 17. The battery bypass pipe 51 is a battery bypass section in which the refrigerant flowing out from the second expansion valve 15 flows by bypassing the battery cooler 50.

A battery bypass opening / closing valve 52 is disposed in the battery bypass pipe 51. The battery bypass opening / closing valve 52 is a battery bypass opening degree adjusting unit that adjusts the opening degree of the battery bypass pipe 51. The battery bypass on-off valve 52 is an electromagnetic valve and is controlled by the control device 40.

The battery bypass pipe 51 and the battery bypass on / off valve 52 are a second flow rate adjusting unit that adjusts the flow rate of the insulating oil flowing into the battery 27. That is, when the battery bypass opening / closing valve 52 increases the opening degree of the battery bypass pipe 51, the flow rate of the refrigerant flowing through the battery cooler 50 is reduced. Therefore, the battery bypass opening / closing valve 52 can adjust the temperature of the battery cooler 50 by adjusting the opening degree of the battery bypass pipe 51, and thus the temperature of the battery 27 can be adjusted.

The refrigeration cycle apparatus of the present embodiment includes a battery cooler 50. The battery cooler 50 is in contact with the battery 27 so as to conduct heat, and the refrigerant flowing out of the second expansion valve 15 flows. The battery cooler 50 and the cooler core evaporator 17 are arranged in series with each other in the flow of the refrigerant. According to this, the battery 27 can be cooled as in the first embodiment.

In the present embodiment, the battery cooler 50 is disposed upstream of the cooler core evaporator 17 in the refrigerant flow.

According to this, since the refrigerant pressure in the battery cooler 50 becomes higher than the refrigerant pressure in the cooler core evaporator 17 due to the pressure loss in the battery cooler 50 and the cooler core evaporator 17, the refrigerant temperature in the battery cooler 50 is increased. It becomes higher than the refrigerant temperature in the cooler core evaporator 17. Therefore, the temperature zone of the battery 27 can be made higher than the temperature zone of the cooler core 32 in accordance with the respective required cooling temperatures of the battery 27 and the cooler core 32.

In the present embodiment, the battery bypass pipe 51 forms a refrigerant flow path through which the refrigerant bypasses the battery cooler 50. Thereby, the temperature of the battery 27 can be adjusted favorably.

(Third embodiment)
In the first embodiment, the insulating oil of the insulating oil circuit 25 is cooled by the low-pressure refrigerant of the refrigeration cycle apparatus 10, but in this embodiment, as shown in FIG. Cooled by the cooling water of the low-temperature cooling water circuit 30.

The refrigeration cycle apparatus 10 of the present embodiment includes an insulating oil cooling heat exchanger 55 instead of the battery evaporator 16 of the first embodiment. The heat exchanger 55 for cooling the insulating oil cools the insulating oil of the insulating oil circuit 25 (in other words, the second heat medium) by exchanging heat between the cooling water of the low-temperature cooling water circuit 30 and the insulating oil of the insulating oil circuit 25. The second heat medium cooling heat exchanger.

In the heat exchanger 55 for cooling the insulating oil, the cooling water absorbs heat from the insulating oil by sensible heat change. That is, in the heat exchanger 55 for cooling the insulating oil, even if the cooling water absorbs heat from the insulating oil, the cooling water remains in a liquid phase and does not change phase. The insulating oil in the insulating oil circuit 25 cooled by the insulating oil cooling heat exchanger 55 flows through the battery 27, whereby the battery 27 is cooled.

The insulating oil cooling heat exchanger 55 is arranged on the downstream side of the cooler core 32 in the flow of the cooling water in the low-temperature cooling water circuit 30. In the cooler core 32 and the insulating oil cooling heat exchanger 55, the cooling water absorbs heat by sensible heat change, so that the cooling water temperature in the insulating oil cooling heat exchanger 55 is higher than the cooling water temperature in the cooler core 32. Therefore, the temperature zone of the battery 27 can be made higher than the temperature zone of the cooler core 32 in accordance with the respective required cooling temperatures of the battery 27 and the cooler core 32.

In the low-temperature cooling water circuit 30, one end of a cooler core bypass pipe 56 is connected to the cooling water outlet side of the cooler core evaporator 17 and the cooling water inlet side of the cooler core 32. The other end of the cooler core bypass pipe 56 is connected to the coolant outlet side of the cooler core 32 and to the coolant inlet side of the heat exchanger 55 for cooling the insulating oil. The cooler core bypass pipe 56 is a cooler core bypass section in which the cooling water flowing out from the cooler core evaporator 17 flows by bypassing the cooler core 32.

In the cooler core bypass pipe 56, a cooler core bypass opening / closing valve 57 is arranged. The cooler core bypass opening / closing valve 57 is a cooler core bypass opening degree adjusting unit that adjusts the opening degree of the cooler core bypass pipe 56. The cooler core bypass opening / closing valve 57 is an electromagnetic valve and is controlled by the control device 40.

The cooler core bypass pipe 56 and the cooler core bypass opening / closing valve 57 are a first flow rate adjusting unit that adjusts the flow rate of the cooling water flowing into the cooler core 32. That is, when the cooler core bypass opening / closing valve 57 increases the opening degree of the cooler core bypass pipe 56, the flow rate of the refrigerant flowing through the cooler core 32 decreases. Therefore, the temperature of the cooler core 32 can be adjusted by the cooler core bypass opening / closing valve 57 adjusting the opening degree of the cooler core bypass pipe 56.

The refrigeration cycle apparatus of the present embodiment includes a heat exchanger 55 for insulating oil cooling and an insulating oil circuit 25. The heat exchanger 55 for cooling the insulating oil cools the insulating oil by exchanging heat between the cooling water and the insulating oil. The insulating oil circuit 25 circulates the insulating oil cooled by the insulating oil cooling heat exchanger 55 to the battery 27. Thereby, the battery 27 can be cooled similarly to the said embodiment.

In this embodiment, the insulating oil cooling heat exchanger 55 is disposed downstream of the cooler core 32 in the flow of the cooling water. According to this, when the cooling water exchanges heat between the cooler core 32 and the insulating oil cooling heat exchanger 55, the cooling water temperature in the insulating oil cooling heat exchanger 55 becomes higher than the cooling water temperature in the cooler core 32. Therefore, the temperature zone of the battery 27 can be made higher than the temperature zone of the cooler core 32 in accordance with the respective required cooling temperatures of the battery 27 and the cooler core 32.

In the present embodiment, the cooler core bypass pipe 56 forms a cooling water flow path in which the cooling water flows through the cooler core 32 in the low-temperature cooling water circuit 30. Thereby, since the flow volume of the cooling water in the cooler core 32 can be adjusted independently with respect to the flow volume of the cooling water in the heat exchanger 55 for insulating oil cooling, the temperature of the cooler core 32 can be adjusted favorably.

In this embodiment, an insulating oil pump 26 is provided. The insulating oil pump 26 adjusts the flow rate of the insulating oil flowing into the battery 27. Thereby, the temperature of the battery 27 can be adjusted favorably.

(Other embodiments)
The above embodiments can be combined as appropriate. The above embodiment can be variously modified as follows, for example.

(1) In each of the above embodiments, the battery 27 is cooled with insulating oil, but may be cooled with various insulating media. For example, the battery 27 may be cooled with an insulating heat medium such as a fluorine-based inert liquid.

(2) A battery cooling heat exchanger may be disposed in the refrigeration cycle apparatus 10 instead of the battery 27 of each of the above embodiments. The battery cooling heat exchanger is an in-vehicle device cooler for cooling a battery (in other words, an in-vehicle device). For example, a battery-cooling heat exchanger is a heat exchanger that cools air blown to a battery by exchanging heat between air blown to the battery and insulating oil.

(3) In the above embodiments, the cooling target devices are the battery 27 and the cooler core 32, but the cooling target devices may be various in-vehicle devices such as an inverter and an intercooler.

The inverter is a power conversion unit that converts DC power supplied from the battery into AC power and outputs it to the traveling motor. The intercooler is a heat exchanger that cools the engine intake air by exchanging heat between the engine intake air that has been compressed by the supercharger and has reached a high temperature and the coolant.

(4) In each of the above embodiments, cooling water is used as the heat medium, but various media such as oil may be used as the heat medium.

Nano fluid may be used as the heat medium. A nanofluid is a fluid in which nanoparticles having a particle size of the order of nanometers are mixed. By mixing the nanoparticles with the heat medium, the following effects can be obtained in addition to the effect of lowering the freezing point and making the antifreeze liquid like cooling water using ethylene glycol.

That is, the effect of improving the thermal conductivity in a specific temperature range, the effect of increasing the heat capacity of the heat medium, the effect of preventing the corrosion of metal pipes and the deterioration of rubber pipes, and the heat medium at an extremely low temperature The effect which improves the fluidity | liquidity of can be acquired.

Such operational effects vary depending on the particle configuration, particle shape, blending ratio, and additional substances of the nanoparticles.

According to this, since the thermal conductivity can be improved, it is possible to obtain the same cooling efficiency even with a small amount of heat medium as compared with the cooling water using ethylene glycol.

Also, since the heat capacity of the heat medium can be increased, it is possible to increase the amount of cold stored heat due to sensible heat of the heat medium itself.

Even if the compressor 11 is not operated by increasing the amount of cold storage heat, it is possible to control the temperature and cooling of the equipment using the cold storage heat for a certain amount of time. Can be realized.

The aspect ratio of the nanoparticles is preferably 50 or more. This is because sufficient thermal conductivity can be obtained. The aspect ratio is a shape index that represents the ratio of the vertical and horizontal dimensions of the nanoparticles.

Nanoparticles containing any of Au, Ag, Cu, and C can be used. Specifically, Au nanoparticle, Ag nanowire, CNT, graphene, graphite core-shell nanoparticle, Au nanoparticle-containing CNT, and the like can be used as the constituent atoms of the nanoparticle.

CNT is a carbon nanotube. The graphite core-shell nanoparticle is a particle body having a structure such as a carbon nanotube surrounding the atom.

(5) In the refrigeration cycle apparatus 10 of each of the above embodiments, a chlorofluorocarbon refrigerant is used as the refrigerant. However, the type of the refrigerant is not limited to this, and various refrigerants may be used.

Claims

A compressor (11) for sucking and compressing and discharging refrigerant;
A radiator (14) for radiating heat from the refrigerant discharged from the compressor;
A decompression section (15) for decompressing the refrigerant radiated by the radiator;
An evaporator (17) for exchanging heat between the refrigerant decompressed by the decompression unit and the heat medium to cool the heat medium;
A first cooling target device (32) and a second cooling target device (27) that are cooled using the cold of the refrigerant decompressed by the decompression unit;
A heat medium circuit (30) for circulating the heat medium cooled by the evaporator only to the first cooling target device among the first cooling target device and the second cooling target device;
A refrigeration cycle apparatus comprising: a flow rate adjusting unit (31, 56, 57) for adjusting a flow rate of the heat medium flowing into the first cooling target device.
The heat medium is a first heat medium;
The evaporator (17) is a first evaporator,
The heat medium circuit (30) is a first heat medium circuit;
The flow rate adjusting unit (31) is a first flow rate adjusting unit,
Furthermore, a second evaporator (16) that cools the second heat medium by exchanging heat between the refrigerant flowing out of the decompression unit and the second heat medium;
A second heat medium circuit (25) for circulating the second heat medium cooled by the second evaporator to the second object to be cooled;
A second flow rate adjustment unit (26) for adjusting the flow rate of the second heat medium flowing into the second cooling target device,
The refrigeration cycle apparatus according to claim 1, wherein the first evaporator and the second evaporator are arranged in series with each other in the flow of the refrigerant.
The first cooling target device (32) is an air cooling heat exchanger that exchanges heat between the air blown into the vehicle interior and the first heat medium,
The second cooling target device (27) is a vehicle-mounted device mounted on a vehicle or a vehicle-mounted device cooler for cooling the vehicle-mounted device,
The refrigeration cycle apparatus according to claim 2, wherein the second evaporator is disposed upstream of the first evaporator in the refrigerant flow.
A refrigerant circulation device (50) that is in contact with the second cooling target device so as to be capable of conducting heat and through which the refrigerant that has flowed out of the decompression unit flows,
The refrigeration cycle apparatus according to claim 1, wherein the refrigerant circulation device and the evaporator are arranged in series with each other in the flow of the refrigerant.
The first cooling target device is an air cooling heat exchanger (32) for exchanging heat between the air blown into the passenger compartment and the heat medium,
The second cooling target device (27) is a vehicle-mounted device mounted on a vehicle or a vehicle-mounted device cooler for cooling the vehicle-mounted device,
The refrigeration cycle apparatus according to claim 4, wherein the refrigerant circulation device is disposed upstream of the evaporator in the refrigerant flow.
The refrigeration cycle apparatus according to claim 4 or 5, wherein the flow rate adjustment unit includes a bypass unit (51) in which the refrigerant flows by bypassing the refrigerant circulation device.
The heat medium is a first heat medium;
The heat medium circuit is a first heat medium circuit (30);
Furthermore, a second heat medium cooling heat exchanger (55) that heat-exchanges the first heat medium and the second heat medium to cool the second heat medium;
The refrigeration cycle apparatus according to claim 1, further comprising a second heat medium circuit (25) that circulates the second heat medium cooled by the second heat medium cooling heat exchanger to the second object to be cooled.
The first cooling target device (32) is an air cooling heat exchanger that exchanges heat between the air blown into the vehicle interior and the second heat medium,
The second cooling target device (27) is a vehicle-mounted device mounted on a vehicle or a vehicle-mounted device cooler for cooling the vehicle-mounted device,
The refrigeration cycle apparatus according to claim 7, wherein the second heat medium cooling heat exchanger is disposed downstream of the air cooling heat exchanger (32) in the flow of the first heat medium.
The flow rate adjusting section includes a bypass section (56) in the first heat medium circuit (30), wherein the first heat medium flows bypassing the air cooling heat exchanger (32). The refrigeration cycle apparatus according to 8.
The flow rate adjusting units (56, 57) are first flow rate adjusting units,
Furthermore, the refrigerating-cycle apparatus as described in any one of Claim 7 thru | or 9 provided with the 2nd flow volume adjustment part (26) which adjusts the flow volume of the said 2nd heat medium which flows into a said 2nd cooling object apparatus.