JP2001030743A - Heat pump air conditioner for electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To configure an air conditioner such that visibility can be assured by defogging window glasses while a heater is on. SOLUTION: This air conditioner is provided with a compressor 1 driven by an electric motor, a four-way valve 2, a heat exchanger for exterior of cabin 3, a heat exchanger for interior of cabin for absorbing heat 4, and an expansion valve 5 disposed between the two heat exchangers 3, 4. A heat exchanger for interior of cabin for discharging heat 6, into which high- temperature high-pressure refrigerant gas pressurized by the compressor 1 during heating is guided, is disposed downstream of indoor circulating air flow of the heat exchanger for interior of cabin for absorbing heat 4. An expansion valve 7 is disposed in a refrigerant piping between the heat exchanger for interior of cabin for discharging heat 6 and the four-way valve 2. Structure to throttle control at least either one of the two expansion valves 5, 7 provides the heat pump air conditioner for an electric vehicle with functions of heating, cooling, and dehumidifying.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pump type air conditioner for an electric vehicle, and more particularly to a heat pump type air conditioner configured to perform desired dehumidification and heating.

[0002]

2. Description of the Related Art FIG. 3 shows a refrigerant system diagram of a conventional air conditioner for an electric vehicle. 3, reference numeral 1 denotes a compressor driven by an electric motor (not shown);
Denotes a four-way valve, 3 denotes a heat exchanger outside the vehicle compartment, 4 denotes a heat exchanger for absorbing heat in the vehicle interior, and 5 denotes an expansion valve, and these are connected by refrigerant piping as shown in the figure. 10 is a fan for the heat exchanger 3 outside the vehicle compartment, 11 is a fan for air circulation in the vehicle compartment provided in the heat exchanger 4 for absorbing heat inside the vehicle compartment, 20 is a drain pan, 21
Indicates a drain discharge pipe.

In the air conditioner of FIG. 3 having the above configuration, when the compressor 1 is driven by an electric motor driven by a battery, the high temperature compressed by the compressor 1 when the air conditioner is in a cooling operation. The high-pressure gas refrigerant flows in the direction indicated by the solid arrow of the four-way valve 2 through the refrigerant pipe, is pressure-fed to the exterior heat exchanger 3, and is cooled and condensed and liquefied by the outside air introduced by the exterior heat exchanger fan 10. I do.

When the condensed and liquefied liquid refrigerant exits the exterior heat exchanger 3, it is sent via a refrigerant pipe to an expansion valve 5, which is also disposed outside the interior of the vehicle, where it becomes an adiabatic expanded low-temperature, low-pressure liquid refrigerant. . The low-temperature and low-pressure liquid refrigerant enters the heat exchanger 4 for absorbing heat inside the vehicle through a refrigerant pipe connecting the heat exchanger 4 for absorbing heat inside the vehicle and the outside of the vehicle. The fan 11 exchanges heat with the circulating air in the passenger compartment sent into the heat exchanger 4 for absorbing heat in the passenger compartment, and cools the circulating air to cool the passenger compartment. The condensed water of the circulating air generated on the surface of the heat exchanger 4 for absorbing heat in the vehicle interior during heat exchange drops into a drain pan 20 which is a receiver for the condensed water, and is discharged outside the vehicle interior via a drain discharge pipe 21. .

On the other hand, the refrigerant which has exchanged heat with the circulating air evaporates and evaporates and passes through the refrigerant pipe connecting the heat exchanger 4 for absorbing heat in the vehicle interior and the four-way valve 2 provided outside the vehicle interior to the four-way valve 2 through a solid arrow. , And returns to the compressor 1 also arranged outside the vehicle compartment.

On the other hand, when the air conditioner is in a heating operation,
The high-temperature and high-pressure gas refrigerant compressed by the compressor 1 is
During the cooling operation via the refrigerant pipe, the four-way valve 2 in which the refrigerant flow path is electrically switched flows in the direction shown by the dashed arrow, is pressure-fed to the heat exchanger 4 for absorbing heat inside the vehicle, and the fan 1 for circulating the inside air.
1 exchanges heat with the circulating air in the passenger compartment sent to the heat exchanger 4 for absorbing heat in the passenger compartment, and heats the circulating air to heat the passenger compartment.

The refrigerant that has exchanged heat with the circulating air is condensed and liquefied and sent to an expansion valve 5 disposed outside the vehicle cabin through a refrigerant pipe to adiabatically expand to become a low-temperature and low-pressure liquid refrigerant. The heat is sent to the outside heat exchanger 3 via the pipe, where the heat is exchanged with the outside air introduced by the outside heat exchanger fan 10 to evaporate to become a low-temperature and low-pressure gas refrigerant. The low-temperature and low-pressure gas refrigerant flows through the four-way valve 2 in the direction of the dashed arrow through the refrigerant pipe and returns to the compressor 1.

[0008]

In the above-mentioned conventional heat pump type air conditioner for an electric vehicle, the heat exchanger 4 for absorbing heat inside the vehicle compartment during the heating operation is provided with the circulating air sent by the fan 11 for circulating the inside air. Only heats the vehicle interior to heat the passenger compartment.However, in the case of heat pump air conditioners for electric vehicles, dehumidifying Heating needs to be done. In this case, it is conceivable to provide an air conditioner in which a heating heat exchanger is separately provided in the vehicle interior and the conventional heat absorbing heat exchanger 4 in the vehicle interior is used as a cooling heat exchanger. A large number of parts such as valves are added, which complicates the system and raises costs.

An object of the present invention is to provide a heat pump type air conditioner for an electric vehicle which has a simple structure so as to perform a dehumidifying / heating operation during a heating operation. .

[0010]

According to the present invention, there is provided an electric motor-driven compressor, a four-way valve,
In a heat pump type air conditioner for an electric vehicle having a heat exchanger for heat absorption outside the vehicle compartment, a heat exchanger for heat absorption inside the vehicle, and an expansion valve provided between the heat exchanger for heat absorption outside the vehicle and the heat absorption space inside the vehicle, A heat exchanger for radiating heat in the vehicle compartment, which is disposed on the downstream side of the circulating air flow of the heat exchanger for absorbing heat in the vehicle compartment and in which a high-temperature and high-pressure gas refrigerant pressurized by the compressor during heating is guided; A heat pump air for an electric vehicle, comprising: an indoor heat dissipation heat exchanger; and an expansion valve disposed in a refrigerant pipe between the four-way valve, and configured to throttle-control at least one of the two expansion valves. Provide a harmony device.

According to the heat pump type air conditioner for an electric vehicle of the present invention, the circulating air heated by the high-temperature and high-pressure gas refrigerant in the vehicle interior heat-exchanger during the heating operation is: Since the air is dehumidified by the heat exchanger for absorbing heat inside the vehicle compartment, it becomes possible to remove the fogging of the window glass during the heating operation.

The present invention also relates to the heat pump type air conditioner for an electric vehicle described above, wherein an outlet of the expansion valve and a suction side of a compressor are connected between a four-way valve and a heat exchanger for radiating heat in the vehicle interior. Another object of the present invention is to provide an air conditioner having a configuration in which an electromagnetic valve that opens during a cooling operation is provided. With this configuration, at the time of cooling operation, the refrigerant remaining in the heat exchanger for heat radiation inside the vehicle and the expansion valve, or the refrigerant pipe connecting them flows to the suction side of the compressor and is effectively used as the refrigerant for cooling. It will be.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a heat pump type air conditioner for an electric vehicle according to the present invention will be specifically described with reference to the embodiments shown in FIGS. In the following embodiments, the same components as those of the conventional apparatus shown in FIG. 3 are denoted by the same reference numerals for simplicity of description, and redundant description thereof will be omitted.

(First Embodiment) First, the first embodiment shown in FIG.
An embodiment will be described. In FIG. 1, reference numeral 6 denotes a heat exchanger for radiating heat in the vehicle compartment, which is disposed downstream of the heat exchanger 4 for absorbing heat in the vehicle compartment with respect to the circulating air from the fan 11 for circulating air in the vehicle compartment. Reference numeral 7 denotes an expansion valve. The heat radiation heat exchanger 6 and the expansion valve 7 are connected to the refrigerant pipe via the four-way valve 2 as shown in the figure. Other configurations are substantially the same as those of the air-conditioning apparatus shown in FIG. 3, and a description thereof will be omitted.

In the air-conditioning apparatus shown in FIG. 1, in the case of cooling operation, the high-temperature and high-pressure gas refrigerant compressed by the compressor 1 is connected to the four-way valve 2 switched to the cooling position by a solid line as in the conventional case. It flows in the direction of the arrow, first heat exchanges in the exterior heat exchanger 3, condenses and liquefies, is throttled by the expansion valve 5, adiabatically expanded, and becomes a low-temperature and low-pressure liquid refrigerant. The liquid refrigerant exchanges heat with the circulating air sent by the vehicle interior air circulation fan 11 in the vehicle interior heat absorption heat exchanger 4 to evaporate and evaporate to become a low-temperature and low-pressure gas refrigerant.
Return to the suction side.

On the other hand, in the heating operation, the high-temperature and high-pressure gas refrigerant compressed by the compressor 1 passes through the four-way valve 2 in which the refrigerant circuit is switched for heating. The cooling air is sent to the heat exchanger 6 for heat radiation through the refrigerant through the refrigerant pipe connecting the heat exchanger 6 and the heat exchanger 6 for heat radiation provided inside the vehicle. This condenses and liquefies and heats the circulating air.

The condensed and liquefied liquid refrigerant passes through the expansion valve 7, passes through the four-way valve 2, returns to the suction side of the compressor 1 through the heat exchanger 3 outside the vehicle compartment, the expansion valve 5, and the heat exchanger 4 for absorbing heat inside the vehicle compartment.
In this case, when the expansion valve 7 is fully opened and the expansion valve 5 is throttled, the outside heat exchanger 3 is on the high-pressure refrigerant side, and is cooled by the outside air introduced by the outside heat exchanger fan 10 to condense and liquefy. Since the heat is dissipated, the heat dissipated by the heat exchanger 6 for radiating the vehicle interior is reduced by that much, and the heating of the circulating air sent by the fan 11 for circulating the air in the vehicle interior is reduced.

The refrigerant condensed and liquefied in the exterior heat exchanger 3 is:
The refrigerant is throttled and adiabatically expanded by the expansion valve 5 whose throttle is controlled, becomes a low-temperature and low-pressure liquid refrigerant, and reaches the heat exchanger 4 for absorbing heat inside the vehicle compartment.
The heat exchange with the circulating air in the cabin sent by the fan 11 for circulating the air in the cabin cools the circulating air in the cabin. The condensed water generated on the surface of the heat exchanger 4 for absorbing heat in the vehicle compartment due to the cooling is dripped on a drain pan 20 serving as a tray thereof, and is discharged outside the vehicle compartment via a drain discharge pipe 21. Thus, the circulating air in the passenger compartment that has passed through the heat exchanger for absorbing heat in the passenger compartment 4 is cooled and cooled.
Dehumidified. The low-temperature and low-pressure gas refrigerant evaporated and vaporized by the heat exchanger 4 for absorbing heat inside the vehicle compartment returns to the suction side of the compressor 1.

On the other hand, when the expansion valve 7 is throttle-controlled and the expansion valve 5 is fully opened, the refrigerant throttle-controlled by the expansion valve 7 has a low temperature.
It becomes a low-pressure liquid refrigerant, reaches the exterior heat exchanger 3, absorbs heat from the outside air introduced by the exterior heat exchanger fan 10,
It reaches the heat exchanger 4 for heat absorption of the vehicle interior through the expansion valve 5 which is fully open.
Then, the heat exchange with the cabin circulating air sent by the cabin air circulating fan 11 is performed to absorb heat from the cabin circulating air, thereby cooling and dehumidifying the cabin circulating air to return to the compressor 1 as a low-temperature and low-pressure gas refrigerant. .

In this case, since the cooling / dehumidifying performance is shared with the heat exchanger 3 outside the vehicle, the cooling / dehumidifying performance of the heat exchanger 4 for absorbing heat inside the vehicle is controlled by fully opening the expansion valve 7 and restricting the expansion valve 5. Is smaller than the case where The expansion valve 7
And 5 are simultaneously subjected to the throttle control, the outside heat exchanger 3 has an intermediate pressure in the above-described case, and the cooling / dehumidifying ability of the heat absorbing heat exchanger 4 in the vehicle compartment can be arbitrarily controlled.

As described above, the air conditioner according to the present embodiment is different from the conventional air conditioner in that the heat exchanger 6 for radiating heat in the vehicle compartment and the expansion valve 7 and the refrigerant pipe connecting them are added to the vehicle. By arranging the indoor air circulation fan 11, the vehicle interior heat absorption heat exchanger 4, and the vehicle interior heat radiation heat exchanger 6 as shown in the drawing, the vehicle interior circulation air sent by the vehicle interior air circulation fan 11 is Although it is cooled and dehumidified by the heat exchanger 4 for absorbing heat in the vehicle compartment, it is heated by the heat exchanger 6 for heat dissipation in the vehicle compartment, thereby enabling dehumidification without lowering the temperature in the vehicle.

Therefore, in the air-conditioning apparatus according to the present embodiment, the circulating air heated by the heat-exchanger 6 in the vehicle interior during heating is cooled and dehumidified by the heat-exchanger 4 in the vehicle interior. It is possible to remove the fogging of the window glass required particularly during the heating period of the air conditioner for use, and to ensure the visibility of the driver. Further, according to the present refrigerant system, the heat exchanger 4 for absorbing heat in the vehicle compartment is always on the low pressure side, so that a laminate evaporator (laminated evaporator) can be used, and the cost can be reduced.

Further, in the air conditioner of the present embodiment, during the cooling operation, the four-way valve 2 is switched to the cooling side so that the refrigerant does not flow through the heat exchanger 6 for heat radiation inside the vehicle compartment and the expansion valve 7; Since the refrigerant that has exited the indoor heat absorbing heat exchanger 4 flows directly into the compressor 1 without passing through the four-way valve 2, the refrigerant cycle is simplified, and pressure loss is reduced.

(Second Embodiment) Next, the second embodiment shown in FIG.
An embodiment will be described. In FIG. 2, reference numeral 8 denotes an electromagnetic valve, and the electromagnetic valve 8 includes the four-way valve 2 and the expansion valve 7.
And a suction line of the compressor 1. The other configuration is substantially the same as the configuration of the air conditioner according to the first embodiment, and a description thereof will be omitted.

In the air conditioner according to the present embodiment having the above configuration, in the heating operation, the solenoid valve 8 provided in the middle of the refrigerant pipe connecting the expansion valve 7 and the suction side of the compressor 1 is closed. The operation of each device,
The flow path of the refrigerant is exactly the same as that of the air conditioner according to the first embodiment shown in FIG. 1, and the dehumidification and heating are performed.

On the other hand, in the cooling operation, the solenoid valve 8 and the expansion valve 7 are controlled to be opened, and the high-temperature and high-pressure gas refrigerant compressed by the compressor 1 by switching the four-way valve 2 is indicated by a solid arrow. Flows in the direction shown in FIG.
The flow returns to the suction side of the compressor 1 through the same route as in the cooling operation of the embodiment.

However, in this case, since the solenoid valve 8 and the expansion valve 7 are open, the four-way valve 2 is switched, and the refrigerant pipe between the four-way valve 2 and the heat exchanger 6 for radiating the vehicle interior, the interior of the vehicle interior, The refrigerant remaining in the refrigerant pipe extending to the four-way valve 2 including the heat exchanger 6 for heat radiation and the heat exchanger 6 for heat radiation inside the vehicle and the expansion valve 7 flows into the suction side of the compressor 1. It is possible to effectively use the charged refrigerant and obtain a predetermined cooling capacity.

[0028]

As described above, the present invention relates to a compressor driven by an electric motor, a four-way valve, a heat exchanger outside the vehicle compartment, a heat exchanger for heat absorption in the vehicle interior, and a heat exchanger outside the vehicle interior and the vehicle interior heat absorption. In a heat pump type air conditioner for an electric vehicle having an expansion valve provided between heat exchangers, the heat exchanger for absorbing heat inside the vehicle cabin is disposed on the downstream side of the circulating air flow of the heat exchanger, and the compressor operates during heating. A heat exchanger for radiating the interior of the vehicle in which the pressurized high-temperature and high-pressure gas refrigerant is guided, and an expansion valve disposed in a refrigerant pipe between the heat exchanger for radiating the interior of the vehicle and the four-way valve, Provided is a heat pump type air conditioner for an electric vehicle, wherein at least one of the two expansion valves is controlled to be throttled.

According to the heat pump type air conditioner for an electric vehicle of the present invention configured as described above, the vehicle interior circulating air is heated by the vehicle interior heat-exchanging heat exchanger into which the high-temperature and high-pressure gas refrigerant is introduced during the heating operation. Is dehumidified by the heat exchanger for absorbing heat inside the vehicle, so that the windowpane can be clouded during the heating operation and the visibility to the driver can be secured.

Further, in the air conditioner according to the present invention, an expansion valve provided between the heat exchanger for absorbing heat inside the vehicle compartment and the heat exchanger for absorbing heat inside the vehicle, and a heat exchanger for heat radiation between the vehicle compartment and the four-way valve. By changing the throttle control of the expansion valve arranged, it is possible to adjust the cooling / dehumidifying capacity in the heat exchanger for heat absorption in the vehicle interior and the heating capacity in the heat exchanger for heat radiation in the vehicle interior. Desired dehumidification can be performed.

Further, in the air conditioner of the present invention, the solenoid valve is connected to the outlet of the expansion valve between the four-way valve and the heat exchanger for radiating the vehicle interior via the suction side of the compressor, and is opened during the cooling operation. In the cooling operation, the refrigerant remaining in the heat exchanger for heat radiation inside the vehicle, the expansion valve and the refrigerant pipe connecting these components flows into the suction side of the compressor and is effectively used as the cooling refrigerant during the cooling operation. Will be.

[Brief description of the drawings]

FIG. 1 is a refrigerant system diagram of a heat pump air conditioner for an electric vehicle according to a first embodiment of the present invention.

FIG. 2 is a refrigerant system diagram of a heat pump air conditioner for an electric vehicle according to a second embodiment of the present invention.

FIG. 3 is a refrigerant system diagram of a conventional heat pump air conditioner for an electric vehicle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 2 Four-way valve 3 Heat exchanger outside a vehicle compartment 4 Heat exchanger for heat absorption inside a vehicle 5 Expansion valve 6 Heat exchanger for heat radiation inside a vehicle 7 Expansion valve 8 Solenoid valve 10 Fan for a heat exchanger outside a vehicle 11 Fan for a vehicle interior air circulation 20 drain pan 21 drain discharge pipe

Claims (2)

[Claims] 1. An electric motor-driven compressor, a four-way valve, a heat exchanger for heat absorption outside a vehicle compartment, a heat exchanger for heat absorption inside a vehicle, and a heat exchanger for heat absorption outside the vehicle and heat radiation for heat absorption inside a vehicle room. In a heat pump type air conditioner for an electric vehicle having an expansion valve, a high-temperature high-pressure gas refrigerant which is disposed on the downstream side of the circulating air flow of the cabin heat absorbing heat exchanger and is pressurized by the compressor during heating. And a expansion valve arranged in a refrigerant pipe between the four-way valve and the heat exchanger for heat radiation inside the vehicle, and at least one of the two expansion valves. A heat pump type air conditioner for an electric vehicle having a heating / cooling and dehumidifying function, characterized in that a throttle control is performed. 2. An electromagnetic valve, which is connected between the four-way valve and the heat exchanger for radiating heat in the vehicle interior through an outlet of the expansion valve and a suction side of the compressor, and is opened during a cooling operation. The heat pump type air conditioner for an electric vehicle according to claim 1, wherein: