JP5917966B2 - Cooling device and vehicle including the same - Google Patents

Description

  The present invention relates to a cooling device and a vehicle including the same, and more particularly to a cooling device that cools a heat generation source using a vapor compression refrigeration cycle and a vehicle including the same.

  In recent years, attention has been focused on hybrid vehicles, fuel cell vehicles, electric vehicles, and the like that travel with the driving force of a motor as one of the environmental countermeasures. In such a vehicle, electric devices such as a motor, a generator, an inverter, a converter, and a battery generate heat when power is transferred. Therefore, it is necessary to cool these electric devices.

  Japanese Unexamined Patent Publication No. 2000-73763 (Patent Document 1) discloses a cooling device for a hybrid vehicle. The cooling device includes a first cooling circuit, a second cooling circuit, and a third cooling circuit. The first cooling circuit selectively or simultaneously cools the high-power system control unit that performs drive control of the drive motor, the engine cylinder head, and the drive motor. The second cooling circuit cools the engine cylinder block. The third cooling circuit cools the high voltage control unit. This cooling device switches the circulation path of the cooling water in the cooling circuit based on the operating states of the engine, the motor, and the air conditioning (see Patent Document 1).

JP 2000-73763 A JP-A-2005-90862 JP-A-11-223406 JP 2007-69733 A

  In the cooling device as described above, an engine-type cooling system and a hybrid-type cooling system that cools the high-power control unit and the like are provided, and a flow path between these cooling systems is switched by a control valve. For this reason, there exists a problem that the structure of a cooling device becomes complicated and cost becomes high.

  Therefore, an object of the present invention is to provide a cooling device that can simplify the cooling system and reduce the cost, and a vehicle including the same.

  According to this invention, the cooling device includes a heat exchanger, a compressor, a first condenser, a second condenser, an expansion valve, a cooling unit, a first branch pipe, and a second branch pipe. And a switching device. A heat exchanger is a heat exchanger for performing air conditioning using a refrigerant. The compressor compresses the refrigerant output from the heat exchanger. The first condenser is provided on the discharge side of the compressor. The second condenser is connected to the first condenser via the first pipe. The expansion valve is provided between the second condenser and the heat exchanger, and is connected to the second condenser via a second pipe. The cooling unit cools the heat generation source using a refrigerant. The first branch pipe branches from the first pipe and is connected to one end of the cooling unit. The second branch pipe is connected to the other end of the cooling unit. The switching device is provided between the second branch pipe and the second condenser, and is configured to be able to switch the refrigerant passage between the second branch pipe and the second condenser. The switching device is configured to be able to switch the first flow path to the second flow path. The first flow path is formed between the third branch pipe and the second branch pipe. The third branch pipe is branched from the first pipe between the branch point of the first branch pipe in the first pipe and the second condenser. The second flow path is formed between the fourth branch pipe and the second branch pipe. The fourth branch pipe is branched from the second pipe.

  Preferably, when the air conditioning is stopped, the switching device switches the first flow path to the second flow path. When the air conditioning stops, the expansion valve is closed.

  Preferably, the switching device includes a first valve and a second valve. The first valve is provided in the third branch pipe. The second valve is provided in the fourth branch pipe. When air conditioning stops, the first valve is closed, the second valve is opened, and the expansion valve is closed.

  Preferably, the switching device includes a three-way valve. The three-way valve is connected to the second branch pipe, the third branch pipe, and the fourth branch pipe. When the air conditioning is stopped, the three-way valve switches the flow path between the second branch pipe and the third branch pipe to the flow path between the second branch pipe and the fourth branch pipe. When the air conditioning stops, the expansion valve is closed.

  Preferably, the cooling device further includes a check valve. The check valve blocks the flow of the refrigerant from the first condenser to the compressor.

  Preferably, the cooling device further includes a gas-liquid separator. The gas-liquid separator is provided at the branch point of the first branch pipe in the first pipe. The gas-liquid separator is for separating the refrigerant cooled by the first condenser into a gas and a liquid, flowing the gas to the second condenser, and flowing the liquid to the cooling unit.

  Preferably, the cooling device further includes a third valve. The third valve is provided between the branch point of the first branch pipe and the branch point of the third branch pipe in the first pipe.

Preferably, the cooling unit is disposed on the lower side in the vertical direction than the second condenser.
Preferably, the heat dissipation capability of the first condenser is higher than the heat dissipation capability of the second condenser.

Preferably, the heat generation source is an electric device mounted on the vehicle.
According to the invention, the vehicle includes any one of the cooling devices described above.

  In the present invention, the cooling device cools the heat source using the vapor compression refrigeration cycle provided for air conditioning using the heat exchanger, and therefore, a dedicated water circulation is used for cooling the heat source. There is no need to provide equipment such as a pump or cooling fan. Thereby, a structure required in order to cool a heat source can be simplified. Therefore, according to the present invention, it is possible to provide a cooling device that can simplify the cooling system and reduce the cost, and a vehicle including the same.

It is a schematic diagram which shows the structure of the cooling device by Embodiment 1 of this invention. It is a Mollier diagram which shows the state of the refrigerant | coolant of a vapor compression refrigeration cycle. It is a schematic diagram which shows the flow of the refrigerant | coolant which cools HV apparatus during the driving | operation of a vapor compression refrigeration cycle. It is a schematic diagram which shows the flow of the refrigerant | coolant which cools HV apparatus in the stop of a vapor compression refrigeration cycle. It is a figure which shows the opening degree of the valve for every operation mode of a cooling device. It is a flowchart which shows an example of the control method of a cooling device. It is a schematic diagram which shows the structure of the cooling device by the modification of Embodiment 1 of this invention. It is a schematic diagram which shows the structure of the cooling device by Embodiment 2 of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

[Embodiment 1]
FIG. 1 is a schematic diagram showing a configuration of a cooling device according to Embodiment 1 of the present invention. The cooling device according to the present embodiment is applied to a hybrid vehicle that uses an engine that is an internal combustion engine and a drive unit that is an electric motor as power sources, and is used to cool an electric device mounted on the hybrid vehicle.

  Referring to FIG. 1, cooling device 1 includes a vapor compression refrigeration cycle 10 (hereinafter, also simply referred to as “refrigeration cycle 10”). The refrigeration cycle 10 is mounted on a hybrid vehicle, for example, to cool the inside of the hybrid vehicle. For cooling using the refrigeration cycle 10, for example, when a switch for performing cooling is turned on, or an automatic control mode for automatically adjusting the indoor temperature of the hybrid vehicle to a set temperature is selected. And when the temperature in the passenger compartment is higher than the set temperature.

  The refrigeration cycle 10 includes a compressor 12, a first condenser 14, a second condenser 15, an expansion valve 16, and a heat exchanger 18. The refrigeration cycle 10 includes a gas-liquid separator 40 disposed on the refrigerant path between the first condenser 14 and the second condenser 15.

  The compressor 12 operates using a motor or engine mounted on the hybrid vehicle as a power source, and compresses the refrigerant gas in an adiabatic manner to obtain a superheated refrigerant gas. The compressor 12 sucks and compresses refrigerant flowing from the heat exchanger 18 when the refrigeration cycle 10 is operated, and discharges high-temperature and high-pressure gas-phase refrigerant into the refrigerant passage 21. The compressor 12 circulates the refrigerant in the refrigeration cycle 10 by discharging the refrigerant into the refrigerant passage 21.

  The first condenser 14 and the second condenser 15 cause the superheated refrigerant gas compressed in the compressor 12 to dissipate heat to the external medium in an isobaric manner to obtain a refrigerant liquid. The high-pressure gas-phase refrigerant discharged from the compressor 12 is condensed (liquefied) by releasing heat to the surroundings and cooling in the first condenser 14 and the second condenser 15. Each of the first condenser 14 and the second condenser 15 includes a tube through which the refrigerant flows, and fins for exchanging heat between the refrigerant flowing through the tube and the air around the condenser.

  The first condenser 14 and the second condenser 15 exchange heat between the cooling air and the refrigerant. The cooling air may be supplied to the first condenser 14 and the second condenser 15 by forced air from a radiator fan provided in a cooling circuit for cooling the engine. The cooling air may be supplied to the first condenser 14 and the second condenser 15 by natural ventilation generated by traveling of the hybrid vehicle. By the heat exchange in the first condenser 14 and the second condenser 15, the temperature of the refrigerant is lowered and the refrigerant is liquefied.

  The expansion valve 16 is expanded by injecting a high-pressure liquid-phase refrigerant flowing through the refrigerant passage 25 from a small hole, and changes into a low-temperature and low-pressure mist refrigerant. The expansion valve 16 depressurizes the refrigerant liquid condensed by the first condenser 14 and the second condenser 15 to obtain wet vapor in a gas-liquid mixed state. Note that the decompressor for decompressing the refrigerant liquid is not limited to the expansion valve 16 that is squeezed and expanded, and may be a capillary tube. Further, the expansion valve 16 can adjust the flow rate of the refrigerant flowing to the heat exchanger 18 by adjusting the valve opening degree. Here, the opening degree of the expansion valve 16 is adjusted according to the refrigerant temperature at the outlet of the heat exchanger 18. Thereby, the amount of refrigerant | coolant according to the cooling capability which the heat exchanger 18 requires in order to cool the air for an air conditioning can be supplied to the heat exchanger 18. FIG.

  The heat exchanger 18 absorbs heat of ambient air introduced so as to come into contact with the heat exchanger 18 by vaporizing the mist refrigerant flowing through the heat exchanger 18. The air-conditioning equipment uses the refrigerant decompressed by the expansion valve 16 to absorb the heat of vaporization when the refrigerant's wet vapor evaporates into refrigerant gas from the air-conditioning air flowing into the interior of the hybrid vehicle. Cool the interior of the vehicle. The air-conditioning air whose temperature has been reduced by the heat being absorbed by the heat exchanger 18 is returned again to the interior of the hybrid vehicle, thereby cooling the interior of the hybrid vehicle. The refrigerant absorbs heat from the surroundings in the heat exchanger 18 and is heated.

  The heat exchanger 18 includes tubes that circulate refrigerant and fins. The fin is a fin for exchanging heat between the refrigerant circulating in the tube and the air around the heat exchanger 18. A wet steam refrigerant circulates in the tube. When the refrigerant circulates in the tube, it evaporates by absorbing the heat of the air in the interior of the hybrid vehicle as latent heat of evaporation via the fins, and further becomes superheated steam by sensible heat. The vaporized refrigerant flows to the compressor 12 via the refrigerant passage 27. The compressor 12 compresses the refrigerant flowing from the heat exchanger 18.

  The refrigeration cycle 10 includes a refrigerant passage 21 that communicates the compressor 12 and the first condenser 14, a refrigerant passage 22, 23, and 24 that communicates the first condenser 14 and the second condenser 15, and a second condensation. A refrigerant passage 25 that communicates between the heat exchanger 15 and the expansion valve 16, a refrigerant passage 26 that communicates between the expansion valve 16 and the heat exchanger 18, and a refrigerant passage 27 that communicates between the heat exchanger 18 and the compressor 12. Including.

  The refrigerant passage 21 is a passage for circulating the refrigerant from the compressor 12 to the first condenser 14. The refrigerant flows between the compressor 12 and the first condenser 14 via the refrigerant passage 21 from the outlet of the compressor 12 toward the inlet of the first condenser 14. The refrigerant passages 22 to 25 are passages for circulating the refrigerant from the first condenser 14 to the expansion valve 16. The refrigerant flows from the first condenser 14 to the second condenser 15 via the refrigerant passage 22 and the refrigerant passages 23 and 24. The refrigerant passage 22 includes a refrigerant passage 22 a from the first condenser 14 to the gas-liquid separator 40, a refrigerant passage 22 b from the gas-liquid separator 40 to the branch point of the refrigerant passage 24, and a branch point of the refrigerant passage 24. To the refrigerant passage 22c from the second condenser 15 to the second condenser 15.

  The refrigerant passage 23 is provided between the gas-liquid separator 40 and the cooling unit 30. The refrigerant passage 24 is provided between the cooling unit 30 and the refrigerant passage 22. The refrigerant passage 25 is provided between the second condenser 15 and the expansion valve 16.

  The refrigerant passage 26 is a passage for circulating the refrigerant from the expansion valve 16 to the heat exchanger 18. The refrigerant flows between the expansion valve 16 and the heat exchanger 18 from the outlet of the expansion valve 16 toward the inlet of the heat exchanger 18 via the refrigerant passage 26. The refrigerant passage 27 is a passage for circulating the refrigerant from the heat exchanger 18 to the compressor 12. The refrigerant flows between the heat exchanger 18 and the compressor 12 from the outlet of the heat exchanger 18 toward the inlet of the compressor 12 via the refrigerant passage 27.

  The refrigeration cycle 10 is configured by connecting the compressor 12, the first condenser 14, the cooling unit 30, the second condenser 15, the expansion valve 16, and the heat exchanger 18 through the refrigerant passages 21 to 27. As the refrigerant of the refrigeration cycle 10, for example, carbon dioxide, hydrocarbons such as propane and isobutane, ammonia, chlorofluorocarbons or water can be used.

  When the refrigerant flowing from the first condenser 14 is in a gas-liquid two-phase state, the gas-liquid separator 40 separates the refrigerant into a gas phase refrigerant and a liquid phase refrigerant. Inside the gas-liquid separator 40, a refrigerant liquid that is a liquid phase refrigerant and a refrigerant vapor that is a gas phase refrigerant are stored. A refrigerant passage 22a, a refrigerant passage 22b, and a refrigerant passage 23 are connected to the gas-liquid separator 40.

  On the outlet side of the first condenser 14, the refrigerant is in a gas-liquid two-phase wet steam state in which a saturated liquid and a saturated steam are mixed. The refrigerant flowing out of the first condenser 14 is supplied to the gas-liquid separator 40 through the refrigerant passage 22a. The gas-liquid two-phase refrigerant flowing into the gas-liquid separator 40 from the refrigerant passage 22 a is separated into a gas phase and a liquid phase inside the gas-liquid separator 40. The gas-liquid separator 40 separates the refrigerant condensed by the first condenser 14 into liquid refrigerant liquid and gaseous refrigerant vapor and temporarily stores them.

  The separated refrigerant liquid flows out of the gas-liquid separator 40 via the refrigerant passage 23. An end portion of the refrigerant passage 23 arranged in the liquid phase in the gas-liquid separator 40 forms an outlet for the liquid-phase refrigerant from the gas-liquid separator 40. The separated refrigerant vapor flows out of the gas-liquid separator 40 via the refrigerant passage 22b. The end of the refrigerant passage 22b disposed in the gas phase in the gas-liquid separator 40 forms an outlet for the gas-phase refrigerant from the gas-liquid separator 40. The vapor-phase refrigerant vapor derived from the gas-liquid separator 40 is condensed by releasing heat to the surroundings and cooling in the second condenser 15.

  Inside the gas-liquid separator 40, the refrigerant liquid accumulates on the lower side and the refrigerant vapor accumulates on the upper side. An end portion of the refrigerant passage 23 for leading the refrigerant liquid from the gas-liquid separator 40 is connected to the bottom of the gas-liquid separator 40. Only the refrigerant liquid is sent out of the gas-liquid separator 40 from the bottom side of the gas-liquid separator 40 via the refrigerant passage 23. An end portion of the refrigerant passage 22 b for leading the refrigerant vapor from the gas-liquid separator 40 is connected to the ceiling portion of the gas-liquid separator 40. Only the refrigerant vapor is sent out of the gas-liquid separator 40 from the ceiling side of the gas-liquid separator 40 via the refrigerant passage 22b. As a result, the gas-liquid separator 40 can reliably separate the gas-phase refrigerant and the liquid-phase refrigerant.

  The path of the refrigerant flowing between the first condenser 14 and the second condenser 15 includes a first path and a second path provided in parallel with the first path. The first path includes a refrigerant passage 22 that is connected from the first condenser 14 to the second condenser 15 via the gas-liquid separator 40. The second path includes refrigerant passages 23 and 24 connected to the refrigerant passage 22 from the gas-liquid separator 40 via the cooling unit 30.

  The liquid refrigerant in the gas-liquid separator 40 flows to the cooling unit 30 via the refrigerant passage 23. The refrigerant that has passed through the cooling unit 30 returns to the refrigerant passage 22 via the refrigerant passage 24. The cooling unit 30 is provided on the second path of the refrigerant that flows from the first condenser 14 toward the second condenser 15.

  A point D shown in FIG. 1 indicates a connection point between the refrigerant passage 22 and the refrigerant passage 24, that is, an end portion on the downstream side of the refrigerant passage 24.

  The cooling unit 30 includes an HV (Hybrid Vehicle) device 31 that is an electric device mounted on the hybrid vehicle, and a refrigerant passage 32 that is a pipe through which the refrigerant flows. The HV device 31 is an example of a heat source. One end of the refrigerant passage 32 is connected to the refrigerant passage 23. The other end of the refrigerant passage 32 is connected to the refrigerant passage 24.

  The refrigerant path connected in parallel with the refrigerant passage 22b includes the refrigerant passage 23 upstream of the cooling unit 30 (the side close to the gas-liquid separator 40), the refrigerant passage 32 included in the cooling unit 30, and cooling. And a refrigerant passage 24 on the downstream side (side closer to the second condenser 15) than the section 30. The refrigerant passage 23 is a passage for allowing a liquid-phase refrigerant to flow from the gas-liquid separator 40 to the cooling unit 30. The refrigerant passage 24 is a passage for circulating the refrigerant from the cooling unit 30 to the point D.

  The refrigerant liquid that has flowed out of the gas-liquid separator 40 flows through the refrigerant passage 23 toward the cooling unit 30. The refrigerant flowing to the cooling unit 30 and flowing through the refrigerant passage 32 takes heat from the HV device 31 as a heat source. The cooling unit 30 cools the HV device 31 using a liquid-phase refrigerant separated in the gas-liquid separator 40 and flowing to the refrigerant passage 32 via the refrigerant passage 23. In the cooling unit 30, the HV equipment 31 is cooled and the refrigerant is heated by heat exchange between the refrigerant flowing through the refrigerant passage 32 and the HV equipment 31. The refrigerant flows from the cooling unit 30 toward the point D via the refrigerant passage 24 and reaches the second condenser 15 via the refrigerant passage 22c.

  The cooling unit 30 is provided in the refrigerant passage 32 so as to have a structure capable of exchanging heat between the HV device 31 and the refrigerant. In the present embodiment, the cooling unit 30 includes, for example, a refrigerant passage 32 formed so that the outer peripheral surface of the refrigerant passage 32 is in direct contact with the housing of the HV device 31. The refrigerant passage 32 has a portion adjacent to the housing of the HV device 31. In this portion, heat exchange can be performed between the refrigerant flowing through the refrigerant passage 32 and the HV device 31.

  The HV device 31 is directly connected to the outer peripheral surface of the refrigerant passage 32 that forms part of the refrigerant path from the first condenser 14 to the second condenser 15 of the refrigeration cycle 10 and is cooled. Since the HV device 31 is disposed outside the refrigerant passage 32, the HV device 31 does not interfere with the flow of the refrigerant flowing through the refrigerant passage 32. Therefore, since the pressure loss of the refrigeration cycle 10 does not increase, the HV equipment 31 can be cooled without increasing the power of the compressor 12.

  Alternatively, the cooling unit 30 may include any known heat pipe that is disposed between the HV device 31 and the refrigerant passage 32. In this case, the HV device 31 is connected to the outer peripheral surface of the refrigerant passage 32 via a heat pipe, and is cooled by transferring heat from the HV device 31 to the refrigerant passage 32 via the heat pipe. Since the heat transfer efficiency between the refrigerant passage 32 and the HV device 31 is increased by using the HV device 31 as a heat pipe heating unit and the refrigerant passage 32 as a heat pipe cooling unit, the cooling efficiency of the HV device 31 is increased. It can be improved. For example, a wick-type heat pipe can be used.

  Since heat can be reliably transferred from the HV device 31 to the refrigerant passage 32 by the heat pipe, there may be a distance between the HV device 31 and the refrigerant passage 32, and the refrigerant passage 32 is brought into contact with the HV device 31. It is not necessary to arrange the refrigerant passage 32 in a complicated manner. As a result, the degree of freedom of arrangement of the HV device 31 can be improved.

  The HV device 31 includes an electrical device that generates heat when power is transferred. The electrical equipment includes, for example, an inverter for converting DC power to AC power, a motor generator that is a rotating electrical machine, a battery that is a power storage device, a boost converter that boosts the voltage of the battery, and a voltage that lowers the voltage of the battery. It includes at least one of a DC / DC converter and the like. The battery is a secondary battery such as a lithium ion battery or a nickel metal hydride battery. A capacitor may be used instead of the battery.

  The heat exchanger 18 is disposed inside a duct 90 through which air flows. The heat exchanger 18 exchanges heat between the refrigerant and the air-conditioning air flowing through the duct 90 to adjust the temperature of the air-conditioning air. The duct 90 has a duct inlet 91 that is an inlet through which air-conditioning air flows into the duct 90 and a duct outlet 92 that is an outlet through which air-conditioning air flows out from the duct 90. A fan 93 is disposed in the vicinity of the duct inlet 91 inside the duct 90.

  When the fan 93 is driven, air flows in the duct 90. When the fan 93 is in operation, air for air conditioning flows into the duct 90 via the duct inlet 91. The air flowing into the duct 90 may be outside air or indoor air of the hybrid vehicle. An arrow 95 in FIG. 1 indicates the flow of air-conditioning air that flows through the heat exchanger 18 and exchanges heat with the refrigerant in the refrigeration cycle 10. During the cooling operation, the air-conditioning air is cooled in the heat exchanger 18, and the refrigerant is heated by receiving heat transfer from the air-conditioning air. An arrow 96 indicates the flow of air-conditioning air that is temperature-adjusted by the heat exchanger 18 and flows out of the duct 90 via the duct outlet 92.

  The refrigerant passes through a refrigerant circulation passage in which the compressor 12, the first condenser 14, the cooling unit 30, the second condenser 15, the expansion valve 16, and the heat exchanger 18 are sequentially connected by refrigerant passages 21 to 27. Circulates in the refrigeration cycle 10. The refrigerant flows through the refrigeration cycle 10 through the points A, B, C, D, E, and F shown in FIG. 1 in order, and the compressor 12, the first condenser 14, and the cooling unit 30. The refrigerant circulates through the second condenser 15, the expansion valve 16, and the heat exchanger 18.

  FIG. 2 is a Mollier diagram showing the state of the refrigerant in the refrigeration cycle 10. The horizontal axis in FIG. 2 indicates the specific enthalpy of the refrigerant, and the vertical axis indicates the absolute pressure of the refrigerant. The unit of specific enthalpy is kJ / kg, and the unit of absolute pressure is MPa. The curves in the figure are the saturated vapor line and saturated liquid line of the refrigerant.

  In FIG. 2, the refrigerant flows from the refrigerant passage 22 at the outlet of the first condenser 14 into the refrigerant passage 23 via the gas-liquid separator 40, cools the HV equipment 31, and passes through the point D from the refrigerant passage 24. Thus, the thermodynamic state of the refrigerant at each point in the refrigeration cycle 10 (ie, points A, B, C, D, E, and F) returning to the inlet of the second condenser 15 is shown. A path through which the refrigerant flows at this time, that is, the refrigerant paths 21 to 27 form a first path.

  As shown in FIG. 2, the superheated vapor refrigerant (point A) sucked into the compressor 12 is adiabatically compressed along the isentropic line in the compressor 12. As the refrigerant is compressed, the pressure and temperature of the refrigerant rise, and the superheated steam is heated to a high temperature and high superheat degree (point B), and the refrigerant flows to the first condenser 14. The gas-phase refrigerant discharged from the compressor 12 is condensed (liquefied) by releasing heat to the surroundings in the first condenser 14 and being cooled. By the heat exchange with the outside air in the first condenser 14, the temperature of the refrigerant is lowered and the refrigerant is liquefied. The high-pressure refrigerant vapor that has entered the first condenser 14 changes from superheated vapor to dry saturated vapor with constant pressure in the first condenser 14, releases condensation latent heat, gradually liquefies, and is vaporized in a gas-liquid mixed state. become. Of the refrigerant in the gas-liquid two-phase state, the condensed refrigerant is in a saturated liquid state (point C).

  The refrigerant is separated into a gas phase refrigerant and a liquid phase refrigerant in the gas-liquid separator 40. Among the gas-liquid separated refrigerant, the liquid-phase refrigerant liquid flows from the gas-liquid separator 40 through the refrigerant passage 23 to the refrigerant passage 32 of the cooling unit 30 to cool the HV equipment 31. In the cooling unit 30, the HV equipment 31 is cooled by releasing heat to the liquid refrigerant in the saturated liquid state that has been condensed through the first condenser 14. By the heat exchange with the HV equipment 31, the refrigerant is heated and the dryness of the refrigerant increases. The refrigerant receives the latent heat from the HV device 31 and partially evaporates to become wet steam in which the saturated liquid and saturated steam are mixed (point D).

  Thereafter, the refrigerant flows into the second condenser 15. The wet steam of the refrigerant is condensed again by exchanging heat with the outside air in the second condenser 15 and cooled, and when all of the refrigerant condenses, it becomes a saturated liquid and further releases sensible heat to supercool the supercooled supercooled liquid. It becomes a cooling liquid (E point). Thereafter, the refrigerant flows into the expansion valve 16 via the refrigerant passage 25. In the expansion valve 16, the refrigerant in the supercooled liquid state is squeezed and expanded, the specific enthalpy does not change, the temperature and pressure are reduced, and the low temperature and low pressure gas-liquid mixed vapor is obtained (point F).

  The wet steam refrigerant that has flowed out of the expansion valve 16 flows into the heat exchanger 18 via the refrigerant passage 26. A wet steam refrigerant flows into the tube of the heat exchanger 18. When the refrigerant flows through the tube of the heat exchanger 18, it absorbs the heat of the air in the interior of the hybrid vehicle through the fins as latent heat of vaporization, and evaporates at a constant pressure. When all the refrigerants are dry and become saturated vapor, the temperature of the refrigerant vapor further rises due to sensible heat and becomes superheated vapor (point A). Thereafter, the refrigerant is sucked into the compressor 12 via the refrigerant passage 27. The compressor 12 compresses the refrigerant flowing from the heat exchanger 18.

  In accordance with such a cycle, the refrigerant continuously repeats the compression, condensation, throttle expansion, and evaporation state changes. In the description of the vapor compression refrigeration cycle described above, the theoretical refrigeration cycle is described. However, in the actual refrigeration cycle 10, it is necessary to consider the loss in the compressor 12, the pressure loss of the refrigerant, and the heat loss. Of course.

  During operation of the refrigeration cycle 10, the refrigerant absorbs heat of vaporization from the air in the cabin of the hybrid vehicle when it evaporates in the heat exchanger 18 acting as an evaporator, thereby cooling the cabin. In addition, the high-pressure liquid refrigerant that flows out from the first condenser 14 and is gas-liquid separated by the gas-liquid separator 40 flows to the cooling unit 30, and heat-exchanges with the HV equipment 31 to cool the HV equipment 31. The cooling device 1 cools the HV equipment 31 that is a heat source mounted on the hybrid vehicle by using the air-conditioning refrigeration cycle 10 in the interior of the hybrid vehicle. Note that the temperature required for cooling the HV device 31 is desirably at least lower than the upper limit value of the target temperature range as the temperature range of the HV device 31.

  Since the HV equipment 31 is cooled by using the refrigeration cycle 10 provided to cool the part to be cooled in the heat exchanger 18, a dedicated water circulation pump or cooling fan is used to cool the HV equipment 31. There is no need to provide such equipment. Therefore, the configuration necessary for the cooling device 1 of the HV equipment 31 can be reduced and the device configuration can be simplified, so that the manufacturing cost of the cooling device 1 can be reduced. In addition, there is no need to operate a power source such as a pump or a cooling fan for cooling the HV equipment 31, and no power consumption is required to operate the power source. Therefore, power consumption for cooling the HV equipment 31 can be reduced.

  In the first condenser 14, it is only necessary to cool the refrigerant to a wet vapor state, the gas-liquid mixed refrigerant is separated by the gas-liquid separator 40, and only the saturated liquid refrigerant is supplied to the cooling unit 30. The The refrigerant in the state of wet steam that has received vaporization latent heat from the HV device 31 and partially vaporized is cooled again by the second condenser 15. The refrigerant changes its state at a constant temperature until the wet vapor state refrigerant is condensed and completely saturated. The second condenser 15 further supercools the liquid-phase refrigerant to the degree of supercooling necessary for cooling the interior of the hybrid vehicle. Since it is not necessary to excessively increase the degree of supercooling of the refrigerant, the capacities of the first condenser 14 and the second condenser 15 can be reduced. Therefore, it is possible to obtain the cooling device 1 that can secure the cooling capacity for the passenger compartment and can reduce the size of the first condenser 14 and the second condenser 15, which is advantageous for in-vehicle use. it can.

  The refrigerant flow path from the gas-liquid separator 40 to the expansion valve 16 is a refrigerant path 22 that does not pass through the cooling unit 30 and a refrigerant path that cools the HV equipment 31 via the cooling unit 30. Refrigerant passages 23 and 24 are provided in parallel. Therefore, only a part of the refrigerant that has flowed out of the first condenser 14 flows to the cooling unit 30. An amount of refrigerant necessary for cooling the HV device 31 is circulated to the cooling unit 30, and the HV device 31 is appropriately cooled. Therefore, it is possible to prevent the HV device 31 from being overcooled.

  A refrigerant path flowing directly from the first condenser 14 to the second condenser 15 and a refrigerant path flowing from the first condenser 14 to the second condenser 15 via the cooling unit 30 are provided in parallel. By allowing only the refrigerant to flow through the refrigerant passages 23 and 24, it is possible to reduce pressure loss when the refrigerant flows into the cooling system of the HV equipment 31. Since all the refrigerant does not flow to the cooling unit 30, it is possible to reduce pressure loss related to the circulation of the refrigerant passing through the cooling unit 30, and accordingly, consumption necessary for the operation of the compressor 12 for circulating the refrigerant. Electric power can be reduced.

  If the low-temperature and low-pressure refrigerant after passing through the expansion valve 16 is used for cooling the HV equipment 31, the cooling capacity of the air in the passenger compartment in the heat exchanger 18 decreases, and the cooling capacity for the passenger compartment decreases. In contrast, in the cooling device 1 of the present embodiment, in the refrigeration cycle 10, the high-pressure refrigerant discharged from the compressor 12 is condensed by both the first condenser 14 and the second condenser 15. The The first condenser 14 and the second condenser 15 are disposed between the compressor 12 and the expansion valve 16, and the cooling unit 30 that cools the HV equipment 31 includes the first condenser 14 and the second condenser 15. It is provided in between. The second condenser 15 is provided on the path of the refrigerant that flows from the cooling unit 30 toward the expansion valve 16.

  By sufficiently cooling the refrigerant heated by the latent heat of vaporization from the HV device 31 in the second condenser 15, the refrigerant is originally required for cooling the interior of the hybrid vehicle at the outlet of the expansion valve 16. Temperature and pressure. Therefore, the amount of heat received from the outside when the refrigerant evaporates in the heat exchanger 18 can be sufficiently increased. Thus, by determining the heat dissipation capability of the second condenser 15 that can sufficiently cool the refrigerant, the HV device 31 can be cooled without affecting the cooling capability of cooling the air in the vehicle compartment. Therefore, both the cooling capacity of the HV device 31 and the cooling capacity for the passenger compartment can be ensured reliably.

  The refrigerant flowing from the first condenser 14 to the cooling unit 30 receives heat from the HV device 31 and is heated when the HV device 31 is cooled. When the refrigerant is heated to the saturated vapor temperature or higher in the cooling unit 30 and the entire amount of the refrigerant is vaporized, the amount of heat exchange between the refrigerant and the HV device 31 is reduced, and the HV device 31 cannot be efficiently cooled. Pressure loss during flow increases. Therefore, it is desirable that the refrigerant is sufficiently cooled in the first condenser 14 so that the entire amount of the refrigerant is not vaporized after the HV device 31 is cooled.

  Specifically, the state of the refrigerant at the outlet of the first condenser 14 is brought close to the saturated liquid, and typically, the refrigerant is on the saturated liquid line at the outlet of the first condenser 14. As a result of the first condenser 14 having the ability to sufficiently cool the refrigerant in this way, the heat radiation ability for releasing heat from the refrigerant of the first condenser 14 is higher than the heat radiation ability of the second condenser 15. By sufficiently cooling the refrigerant in the first condenser 14 having a relatively large heat dissipation capability, the refrigerant that has received heat from the HV device 31 can be kept in a wet steam state, and the heat of the refrigerant and the HV device 31 can be maintained. Since reduction of the exchange amount can be avoided, the HV device 31 can be cooled sufficiently efficiently. The refrigerant in the wet vapor state after cooling the HV device 31 is efficiently cooled again in the second condenser 15 and is cooled to the state of the supercooled liquid below the saturation temperature. Therefore, it is possible to provide the cooling device 1 that secures both the cooling capacity for the passenger compartment and the cooling capacity of the HV device 31.

  The refrigerant in a gas-liquid two-phase state at the outlet of the first condenser 14 is separated into a gas phase and a liquid phase in the gas-liquid separator 40. The gas-phase refrigerant separated by the gas-liquid separator 40 flows through the refrigerant passage 22 and is directly supplied to the second condenser 15. The liquid phase refrigerant separated by the gas-liquid separator 40 flows through the refrigerant passage 23 and is supplied to the cooling unit 30 to cool the HV equipment 31. This liquid-phase refrigerant is a truly saturated liquid refrigerant with no excess or deficiency. By taking out only the liquid-phase refrigerant from the gas-liquid separator 40 and flowing it to the cooling unit 30, efficient cooling using the latent heat of the refrigerant becomes possible. The device 31 can be cooled. Therefore, the cooling device 1 in which the cooling capacity of the HV device 31 is improved can be provided.

  By introducing the refrigerant in a saturated liquid state at the outlet of the gas-liquid separator 40 into the refrigerant passage 32 that cools the HV equipment 31, the refrigerant flows through the cooling system of the HV equipment 31 including the refrigerant passages 23 and 24 and the refrigerant passage 32. Among the refrigerants, the gas-phase refrigerant can be minimized. Therefore, the flow velocity of the refrigerant vapor flowing through the cooling system of the HV device 31 can be prevented from increasing and the pressure loss can be suppressed, and the power consumption of the compressor 12 for circulating the refrigerant can be reduced. Deterioration can be avoided.

  A refrigerant liquid in a saturated liquid state is stored inside the gas-liquid separator 40. The gas-liquid separator 40 functions as a liquid accumulator that temporarily stores a liquid refrigerant that is a liquid refrigerant. By storing a predetermined amount of the refrigerant liquid in the gas-liquid separator 40, the flow rate of the refrigerant flowing from the gas-liquid separator 40 to the cooling unit 30 can be maintained even when the load changes. Since the gas-liquid separator 40 has a liquid reservoir function and becomes a buffer against load fluctuations and can absorb the load fluctuations, the cooling performance of the HV equipment 31 can be stabilized.

  Referring to FIG. 1 again, the cooling device 1 includes a communication path 51 and a switching device constituted by the expansion valve 16 and the switching valve 53. The communication passage 51 communicates the refrigerant passage 24 and the refrigerant passage 25. The refrigerant passage 24 is divided into a refrigerant passage 24a from the cooling unit 30 to the branch point with the communication passage 51 and a refrigerant passage 24b from the branch point with the communication passage 51 to the refrigerant passage 22b side.

  The switching valve 53 includes a valve 57 and a valve 58. The valve 57 is provided in the refrigerant passage 24b and regulates the flow of the refrigerant in the refrigerant passage 24b. The valve 58 is provided in the communication path 51 and restricts the flow of the refrigerant in the communication path 51. By opening and closing the valves 57 and 58, a path through which the refrigerant flows after cooling the HV device 31 is routed to the second condenser 15 via the refrigerant paths 24b and 22c, and via the communication path 51 and the refrigerant path 25. Thus, it is possible to switch to one of the paths leading to the second condenser 15.

  More specifically, during the cooling operation of the refrigeration cycle 10, the valve 58 is fully closed (valve opening 0%), the valve 57 is fully opened, and the valve opening of the expansion valve 16 is set to the outlet of the heat exchanger 18. Adjust according to the refrigerant temperature. Thereby, the refrigerant flowing through the refrigerant passage 24 after cooling the HV device 31 can be reliably circulated to the second condenser 15 via the refrigerant passage 22.

  On the other hand, while the refrigeration cycle 10 is stopped, the valve 58 is fully opened and the expansion valve 16 and the valve 57 are fully closed. As a result, the refrigerant flowing through the refrigerant passage 24a after cooling the HV equipment 31 is circulated to the second condenser 15 via the communication passage 51, and the second cooling unit 30 and the second refrigerant are not circulated through the compressor 12. An annular path for circulating the refrigerant can be formed between the condenser 15 and the condenser 15.

  FIG. 3 is a schematic diagram showing the flow of the refrigerant that cools the HV equipment 31 during operation of the refrigeration cycle 10. FIG. 4 is a schematic diagram showing the flow of the refrigerant that cools the HV equipment 31 while the refrigeration cycle 10 is stopped. FIG. 5 is a view showing the opening degree of the switching device (expansion valve 16, valves 57, 58) for each operation mode of the cooling device 1. Of the operation modes shown in FIG. 5, the “air conditioner operation mode” indicates a case where the refrigeration cycle 10 shown in FIG. 3 is operated, that is, a case where the compressor 12 is operated and the refrigerant is circulated throughout the refrigeration cycle 10. . On the other hand, the “heat pipe operation mode” refers to the case where the refrigeration cycle 10 shown in FIG. 4 is stopped, that is, the compressor 12 is stopped and the cooling unit 30 and the second condenser 15 are connected via an annular path. The case where the refrigerant is circulated is shown. In the heat pipe operation mode, the compressor 12 may temporarily operate when dryout occurs. Thereby, the amount of refrigerant in the heat pipe cycle can be increased to suppress dryout.

  As shown in FIGS. 3 and 5, when in the “air conditioner operation mode” in which the compressor 12 is driven and the refrigeration cycle 10 is operating, the expansion valve 16 is operated according to the refrigerant temperature at the outlet of the heat exchanger 18. The opening is adjusted. The valve 57 is fully opened and the valve 58 is fully closed. As described above, the switching device is operated so that the refrigerant flows from the cooling unit 30 to the expansion valve 16 via the second condenser 15. Thereby, the path | route of a refrigerant | coolant is selected so that a refrigerant | coolant may flow the whole cooling device 1. FIG. Therefore, the cooling capacity of the refrigeration cycle 10 can be secured and the HV equipment 31 can be efficiently cooled.

  As shown in FIGS. 4 and 5, in the “heat pipe operation mode” in which the compressor 12 is stopped and the refrigeration cycle 10 is stopped, the refrigerant circulates between the cooling unit 30 and the second condenser 15. The switching device is operated as follows. That is, when the expansion valve 16 and the valve 57 are fully closed and the valve 58 is fully opened, the refrigerant flows through the communication passage 51 without flowing from the refrigerant passage 24a to the refrigerant passage 24b. As a result, the second condenser 15 reaches the cooling unit 30 through the refrigerant passage 25, the communication passage 51, and the refrigerant passage 24a in this order, and further the refrigerant passage 23, the gas-liquid separator 40, and the refrigerant passage 22 in order. A closed annular path is formed which passes back to the second condenser 15. The path through which the refrigerant flows, that is, the refrigerant path 22, the refrigerant path 23, the refrigerant path 24a, the refrigerant path 25, and the communication path 51 form a second path.

  Through this annular path, the refrigerant can be circulated between the second condenser 15 and the cooling unit 30 without the compressor 12 operating. The refrigerant vapor evaporated by heat exchange in the cooling unit 30 flows to the second condenser 15 through the refrigerant passage 23, the gas-liquid separator 40, and the refrigerant passage 22 in order. In the second condenser 15, the refrigerant vapor is cooled and condensed by the traveling wind of the hybrid vehicle or the ventilation from the radiator fan. The refrigerant liquid liquefied by the second condenser 15 returns to the cooling unit 30 via the refrigerant passage 25, the communication passage 51, and the refrigerant passage 24a.

  Thus, a heat pipe is formed by the annular path passing through the cooling unit 30 and the second condenser 15, with the HV device 31 as a heating unit and the second condenser 15 as a cooling unit. Therefore, even when the refrigeration cycle 10 is stopped, that is, when cooling for the hybrid vehicle is stopped, the HV equipment 31 can be cooled without having to always start the compressor 12. Since it is not necessary to always operate the compressor 12 for cooling the HV equipment 31, the power consumption of the compressor 12 can be reduced and the fuel efficiency of the hybrid vehicle can be improved. Since the life can be extended, the reliability of the compressor 12 can be improved.

  3 and 4 show the ground surface 60. In the vertical direction perpendicular to the ground surface 60, the cooling unit 30 is disposed below the second condenser 15.

  In this case, the refrigerant vapor heated and vaporized in the cooling unit 30 ascends in the annular path and reaches the second condenser 15, is cooled in the second condenser 15, is condensed, and becomes a liquid refrigerant. Due to the action, it descends in the annular path and returns to the cooling unit 30. That is, a thermosiphon heat pipe is formed by the cooling unit 30, the second condenser 15, and the refrigerant path (that is, the second passage) connecting them. Since the heat transfer efficiency from the HV device 31 to the second condenser 15 can be improved by forming the heat pipe, the HV device 31 can be used without applying power even when the refrigeration cycle 10 is stopped. Can be cooled more efficiently.

  When in the heat pipe operation mode, there may be a phenomenon of dryout in which all of the refrigerant dries out if the amount of refrigerant in the second passage is insufficient with respect to the amount of heat radiation required to protect the HV equipment 31. . When dryout occurs, the ability to cool the HV device 31 decreases, and the temperature of the HV device 31 may increase. Therefore, the refrigerant is supplied into the second passage via the refrigerant passage 21 and the first condenser 14 by temporarily operating the compressor 12. Thereby, the refrigerant | coolant amount in a 2nd channel | path can be increased.

  The cooling device 1 further includes a check valve 54. The check valve 54 is disposed in the refrigerant passage 21. The check valve 54 allows the refrigerant flow from the compressor 12 toward the first condenser 14 and prohibits the reverse refrigerant flow. In this way, in the heat pipe operation mode shown in FIG. 4, a closed loop refrigerant path for circulating the refrigerant between the second condenser 15 and the cooling unit 30 can be reliably formed.

  By providing the check valve 54, the flow of the refrigerant from the first condenser 14 toward the compressor 12 can be surely prohibited. Therefore, when the refrigeration cycle 10 is stopped using the heat pipe formed by the annular refrigerant path. Of the cooling capacity of the HV equipment 31 can be prevented. Therefore, the HV device 31 can be efficiently cooled even when the cooling for the passenger compartment of the hybrid vehicle is stopped.

  FIG. 6 is a flowchart illustrating an example of a method for controlling the cooling device 1. Note that the control is not limited to processing by software, and processing by dedicated hardware (electronic circuit) is also possible.

  As shown in FIG. 6, first, in step (S10), it is determined whether or not the air conditioner is turned on. The on / off switching of the air conditioner is performed by an occupant operating an air conditioning control panel provided on the instrument panel in front of the hybrid vehicle.

  When it is determined in step (S10) that the air conditioner is on, the process proceeds to step (S20), and the cooling device 1 cools the HV device 31 in the air conditioner operation mode. That is, a signal for commanding opening / closing of the switching device is transmitted to the expansion valve 16 and the valves 57, 58, the valve 57 is fully opened, the valve 58 is fully closed, and the opening degree of the expansion valve 16 is adjusted. Thereby, the liquid refrigerant separated by the gas-liquid separator 40 among the refrigerant after being cooled by exchanging heat with the outside air by the first condenser 14 is circulated to the cooling unit 30. The HV device 31 is cooled by exchanging heat between the refrigerant flowing through the refrigerant passage 32 and the HV device 31. Thereafter, the refrigerant is cooled again by the second condenser 15, and a sufficient amount of refrigerant is circulated to the heat exchanger 18 to cool the air for air conditioning.

  In addition, when it is judged that the passenger of the hybrid vehicle operates the control panel to turn on the air conditioner, or the HV equipment 31 needs to be cooled in the air conditioner operation mode, the HV equipment is operated in the air conditioner operation mode. 31 may be cooled. For example, when the outside air temperature is higher than a predetermined temperature (for example, 25 ° C.), when the air-conditioning air is higher than a predetermined temperature (for example, 20 ° C.), or when the amount of the refrigerant liquid in the gas-liquid separator 40 is predetermined. The compressor 12 may be activated when it is less than the amount of the compressor 12.

  Alternatively, the HV device 31 may be cooled in the air conditioner operation mode even when the hybrid vehicle travels in a situation where the amount of heat generated by the HV device 31 is large, for example, when traveling on an uphill. The cooling capacity with which the cooling device 1 cools the HV equipment 31 is relatively greater in the air conditioner operation mode in which the compressor 12 is operated than in the heat pipe operation mode. Therefore, when the heat generation amount of the HV device 31 is large, the HV device 31 can be reliably prevented from being overheated by operating the cooling device 1 in the air conditioner operation mode to cool the HV device 31.

  When it is determined in step (S10) that the air conditioner is off, the process proceeds to step (S30), and the cooling device 1 cools the HV equipment 31 in the heat pipe operation mode. That is, a signal instructing opening / closing of the switching device is transmitted to the expansion valve 16 and the valves 57 and 58, the expansion valve 16 and the valve 57 are fully closed, and the valve 58 is fully opened. Thus, an annular path for circulating the refrigerant is formed between the cooling unit 30 and the second condenser 15 to form a thermosiphon heat pipe. The liquid phase refrigerant cooled in the second condenser 15 is circulated to the cooling unit 30 by the action of gravity, and the HV equipment 31 is cooled by exchanging heat between the refrigerant flowing in the refrigerant passage 32 and the HV equipment 31. To do. The refrigerant vapor heated and vaporized by the cooling unit 30 rises in the annular path and reaches the second condenser 15 again.

  Subsequently, in step (S40), it is determined whether or not the occurrence of dryout is detected. For example, the cooling device 1 determines that the dryout has occurred when the temperature detected by the sensor that detects the temperature of the heat generating component of the HV device 31 exceeds the upper limit value. The cooling device 1 may determine the occurrence of dryout based on the difference between the temperature of the refrigerant flowing into the cooling unit 30 and the temperature of the refrigerant flowing out of the cooling unit 30. Furthermore, the cooling device 1 may determine that the dryout has occurred when the temperature detected by the sensor that detects the surface temperature of the cooling unit 30 exceeds the upper limit value. In this case, the temperature sensor may be installed in the vicinity of the refrigerant flow path and the heat generating component.

  If it is determined in step (S40) that a dryout has occurred, the process proceeds to step (S50), and the cooling device 1 temporarily operates the compressor 12. Thereby, the refrigerant compressed by the compressor 12 is supplied into the second passage via the first condenser 14. Thereby, the quantity of the refrigerant | coolant which flows through the 2nd channel | path increases. Therefore, the temperature rise of the HV device 31 can be suppressed.

  When it is determined in step (S40) that no dryout has occurred, the process proceeds to step (S60), and the cooling device 1 stops the compressor 12.

  As described above, in the first embodiment, the HV equipment 31 is cooled using the refrigeration cycle 10 provided to perform air conditioning using the heat exchanger 18, and therefore, the HV equipment 31 is cooled. Therefore, it is not necessary to provide a device such as a dedicated water circulation pump or a cooling fan. Thereby, a structure required in order to cool the HV apparatus 31 can be simplified. Therefore, according to this Embodiment 1, a cooling system can be simplified and cost can be reduced.

  Further, in the first embodiment, the cooling device 1 is an HV device 31 that is a heat source in both the “air conditioner operation mode” in which air conditioning is performed and the “heat pipe operation mode” in which air conditioning is stopped. Can be cooled. In the heat pipe operation mode, it is not necessary to always operate the compressor 12 for cooling the HV equipment 31. Therefore, the power consumption of the compressor 12 can be reduced and the fuel efficiency of the hybrid vehicle can be improved. In addition, the life of the compressor 12 can be extended, so the reliability of the compressor 12 can be improved.

  In the first embodiment, the cooling device 1 controls the switching device in accordance with the operation or stop of the air conditioning. As a result, switching between the air conditioner operation mode and the heat pipe operation mode can be performed more reliably, and the refrigerant can be circulated through an appropriate route for each operation mode.

  In the first embodiment, the heat dissipation capability of the first condenser 14 is higher than the heat dissipation capability of the second condenser 15. Thus, by sufficiently cooling the refrigerant in the first condenser 14 having a relatively large heat dissipation capability, the refrigerant that has received heat from the HV device 31 can be kept in a wet steam state. Therefore, the HV device 31 can be cooled sufficiently efficiently. The refrigerant in the wet vapor state after cooling the HV device 31 is efficiently cooled again in the second condenser 15 and is cooled to the state of the supercooled liquid below the saturation temperature. Therefore, according to this Embodiment 1, both the cooling capacity for vehicle interiors and the cooling capacity of the HV equipment 31 can be ensured.

  Further, in the first embodiment, a heat pipe cycle is formed between the second condenser 15 and the cooling unit 30 in the heat pipe operation mode. This configuration can be configured with a smaller number of valves than the configuration in which a heat pipe cycle is formed between the first condenser 14 and the cooling unit 30. Therefore, cost can be reduced.

  In the first embodiment, when the air conditioner operation mode is switched to the heat pipe operation mode, a path is formed in which the refrigerant that has been supercooled by the second condenser flows into the cooling unit 30. Thereby, the HV equipment 31 can be cooled with the refrigerant in a low temperature state. Therefore, it can suppress that the HV apparatus 31 becomes high temperature until the operation | movement of a heat pipe cycle starts.

  Moreover, in this Embodiment 1, the cooling device 1 is provided with the gas-liquid separator 40 which isolate | separates the refrigerant | coolant which flows in from the 1st condenser 14 into a gaseous-phase refrigerant | coolant and a liquid phase refrigerant | coolant. As a result, only the liquid phase refrigerant can be taken out from the gas-liquid separator 40 and flowed to the cooling unit 30. For this reason, since the capability of the 1st condenser 14 can be utilized to the maximum and the HV apparatus 31 can be cooled, the cooling device 1 which improved the cooling capability of the HV apparatus 31 can be provided.

  In the first embodiment, the cooling device 1 further includes a check valve that blocks the flow of the refrigerant from the first condenser 14 to the compressor 12. Thereby, in the heat pipe operation mode, a closed-loop refrigerant path for circulating the refrigerant between the second condenser 15 and the cooling unit 30 can be reliably formed.

  In the first embodiment, the cooling unit 30 is arranged on the lower side in the vertical direction than the second condenser 15. As a result, the refrigerant vapor heated and vaporized in the cooling unit 30 rises in the annular path and reaches the second condenser 15, is cooled in the second condenser 15, is condensed, and becomes a liquid refrigerant. Due to the action, it descends in the annular path and returns to the cooling unit 30. For this reason, since the heat transfer efficiency from the HV device 31 to the second condenser 15 can be improved by forming the heat pipe, even when the refrigeration cycle 10 is stopped, without applying power, The HV device 31 can be cooled more efficiently.

[Modification]
The modification of the first embodiment of the present invention differs from the first embodiment in that a valve 59 is provided in the refrigerant passage 22b instead of the gas-liquid separator 40. Thereby, it is possible to reliably flow the refrigerant through the cooling unit 30 in the air conditioner operation mode without providing the gas-liquid separator 40.

  FIG. 7 is a schematic diagram showing a configuration of a cooling device according to a modification of the first embodiment of the present invention. With reference to FIG. 7, the cooling device 1 includes a valve 59. The valve 59 is provided in the refrigerant passage 22b.

  When the cooling device 1 is in the air conditioner operation mode, the amount of refrigerant necessary for cooling the HV device 31 is allowed to flow from the first condenser 14 to the cooling unit 30 by adjusting the opening of the valve 59. it can. Thereby, since a refrigerant | coolant can be reliably flowed through the cooling unit 30, the capability of the 1st condenser 14 can be utilized to the maximum and the HV apparatus 31 can be cooled. Therefore, the cooling device 1 in which the cooling capacity of the HV device 31 is improved can be provided. On the other hand, the cooling device 1 fully opens the valve 59 in the heat pipe operation mode. Thereby, a heat pipe cycle can be formed reliably.

  As described above, also in the modified example of the first embodiment, the HV device 31 can be cooled by reliably flowing the coolant through the cooling unit 30 in the air conditioner operation mode.

[Embodiment 2]
The second embodiment of the present invention is different from the first embodiment in that a three-way valve 55 is provided instead of the valves 57 and 58. Thereby, the number of valves for switching the refrigerant passage can be reduced.

  FIG. 8 is a schematic diagram showing a configuration of a cooling device according to Embodiment 2 of the present invention. Referring to FIG. 8, cooling device 1 </ b> A includes a three-way valve 55. The three-way valve 55 is provided at a branch point between the refrigerant passage 36 and the communication passage 51.

  The cooling device 1A operates the three-way valve 55 so that the refrigerant flows between the refrigerant passage 24a and the refrigerant passage 24b in the air conditioner operation mode. Thereby, the refrigerating cycle 10 is formed. On the other hand, the cooling device 1A operates the three-way valve 55 so that the refrigerant flows between the refrigerant passage 24a and the communication passage 51 in the heat pipe operation mode. Thereby, a heat pipe cycle is formed.

  As described above, in the second embodiment, the number of valves for switching between the air conditioner operation mode and the heat pipe operation mode can be reduced as compared with the first embodiment. Therefore, according to the second embodiment, the cost of the cooling device can be further reduced.

  The cooling device of the present invention can be applied not only to a hybrid vehicle using an engine and an electric motor as a power source, but also to an electric vehicle and a fuel cell vehicle using only an electric motor as a power source.

  In the embodiments described so far, the cooling apparatuses 1 and 1 </ b> A for cooling the electric devices mounted on the hybrid vehicle have been described using the HV device 31 as an example. The electric device is not limited to the exemplified electric device such as an inverter and a motor generator as long as it is an electric device that generates heat at least by operation, and may be any electric device.

  In the embodiments described so far, the cooling apparatuses 1 and 1A including the check valve 54 have been described. However, a configuration without the check valve 54 may be employed.

  In the above, the HV device 31 corresponds to an example of the “heat generation source” in the present invention. The valve 57 corresponds to an embodiment of the “first valve” in the present invention, the valve 58 corresponds to an embodiment of the “second valve” in the present invention, and the valve 59 corresponds to the “first valve” in the present invention. This corresponds to an example of the “third valve”. The refrigerant passage 22 corresponds to an example of “first piping” in the present invention, and the refrigerant passage 25 corresponds to an example of “second piping” in the present invention. The refrigerant passage 23 corresponds to an example of the “first branch pipe” in the present invention, and the refrigerant passage 24a corresponds to an example of the “second branch pipe” in the present invention. The refrigerant passage 24b corresponds to one embodiment of the “third branch pipe” in the present invention, and the communication passage 51 corresponds to one embodiment of the “fourth branch pipe” in the present invention.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.

  1, 1A cooling device, 10 vapor compression refrigeration cycle, 12 compressor, 14 first condenser, 15 second condenser, 16 expansion valve, 18 heat exchanger, 30 cooling section, 31 HV equipment, 40 gas-liquid separation , 51 communication path, 53 switching valve, 54 check valve, 55 three-way valve, 57, 58, 59 valve, 60 ground.

Claims (11)

A heat exchanger for air conditioning using a refrigerant;
A compressor that compresses the refrigerant output from the heat exchanger;
A first condenser and a second condenser provided on the discharge side of the compressor ;
An expansion valve that is provided between the heat exchanger and the second condenser,
A first refrigerant passage provided between the first condenser and the second condenser;
A second refrigerant passage provided between the second condenser and the expansion valve;
A cooling unit that cools the heat source using the refrigerant;
A third refrigerant passage provided between the first branch portion provided in the first refrigerant passage and the cooling portion;
A fourth refrigerant passage provided between the cooling portion and a second branch portion provided downstream of the first branch portion in the first refrigerant passage;
A fifth refrigerant passage provided between a third branch portion provided in the second refrigerant passage and a fourth branch portion provided in the fourth refrigerant passage;
A switching valve for switching between the flow of the first refrigerant and the flow of the second refrigerant,
The fourth refrigerant passage is
A sixth refrigerant passage between the cooling part and the fourth branch part;
A seventh refrigerant passage between the fourth branch part and the second branch part,
The flow of the first refrigerant is the flow of the refrigerant from the first condenser toward the expansion valve via the third refrigerant passage, the cooling unit, the fourth refrigerant passage, and the second condenser. Yes,
When the expansion valve is closed, the flow of the second refrigerant is such that the fifth refrigerant passage, the sixth refrigerant passage, and the third refrigerant are between the second condenser and the cooling unit. A cooling device, which is a flow of the refrigerant in an annular path formed by a passage and the first refrigerant passage . When the air conditioning stops,
The switching valve switches the flow of the first refrigerant to the flow of the second refrigerant ,
The cooling device according to claim 1, wherein the expansion valve is closed. The switching valve is
A first valve provided in the seventh refrigerant passage ;
A second valve provided in the fifth refrigerant passage ,
When the air conditioning stops,
The first valve is closed;
The second valve is opened;
The cooling device according to claim 1, wherein the expansion valve is closed. The switching valve includes a three-way valve connected to the sixth refrigerant passage , the seventh refrigerant passage, and the fifth refrigerant passage ,
When the air conditioning stops,
The three-way valve allows the sixth refrigerant passage and the fifth refrigerant passage to flow,
The cooling device according to claim 1, wherein the expansion valve is closed.   The cooling device according to any one of claims 1 to 4, further comprising a check valve that blocks the flow of the refrigerant from the first condenser to the compressor. The first branch part includes a gas-liquid separator,
The gas-liquid separator, the refrigerant cooled in the first condenser and separated into gas and liquid, flowing the gas into the second condenser, is configured to flow the liquid into said cooling unit that, the cooling device according to any one of claims 1 to 5. The cooling device according to any one of claims 1 to 5, further comprising a third valve provided between the first branch portion and the second branch portion .   The cooling device according to any one of claims 1 to 7, wherein the cooling unit is disposed on a lower side in the vertical direction than the second condenser.   The cooling device according to any one of claims 1 to 8, wherein the heat dissipation capability of the first condenser is higher than the heat dissipation capability of the second condenser.   The cooling device according to any one of claims 1 to 9, wherein the heat source is an electrical device mounted on a vehicle.   A vehicle comprising the cooling device according to claim 1.

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