JPH10315755A - Air conditioner for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry out defrosting operation rapidly and positively and improve heating performance effectively. SOLUTION: An air conditioner for a vehicle is provided with an outdoor heat exchanger 64 that absorbs heat by evaporating a cooling medium at the time of heating operation, and a radiator 92 that cools cooling water becoming high in temperature after cooling a driving system 90. The radiator 92 is arranged in front of the outdoor heat exchanger 64 in the lengthwise direction of the vehicle. The outdoor heat exchanger 64 therefore absorbs exhaust heat from the radiator 92 so as to positively impede frosting of the outdoor heat exchanger 64 and to improve heating performance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle air conditioner having a compressor for compressing and sending out a heat medium.

[0002]

2. Description of the Related Art In general, various types of air conditioners such as a semi-auto air conditioner system, a full auto air conditioner system, and a reheat system are employed for performing air conditioning in a vehicle cabin.

In a refrigeration cycle of this type of air conditioner, a cooling medium is generally compressed by a compressor and discharged as a high-temperature and high-pressure gas refrigerant, and the high-temperature and high-pressure gas refrigerant is sent to an outdoor heat exchanger. After being condensed, the cooling medium in the form of a low-temperature and low-pressure mist is supplied to an evaporator (indoor heat exchanger) through an expansion valve (or a capillary tube) as an expansion means. Therefore, the cooling medium absorbs heat from the air around the evaporator, evaporates, becomes a gaseous refrigerant, and is sucked into the compressor again.

When the above air conditioner is used in a heating mode, heat is absorbed by exchanging heat of a cooling medium with the outside air in an outdoor heat exchanger outside the vehicle compartment. Frost is likely to be caused. As a result, the amount of heat absorbed by the outdoor heat exchanger may decrease, and the heating capacity may decrease. Therefore, the defrosting operation is usually performed.
However, during the defrosting operation, the heating operation is stopped, and there is a problem that it takes a considerable time until the defrosting operation is completed and a stable operation state by the heating operation is reached.

Therefore, for example, Japanese Patent Application Laid-Open No. 8-258548
As disclosed in Japanese Patent Application Laid-Open Publication No. H10-115, there is known a technique in which a first passage for flowing a first fluid and a second passage for flowing a second fluid are provided inside an outdoor heat exchanger. Therefore, for example, when a low-temperature and low-pressure refrigerant and a coolant for a heat-generating component such as a drive motor are caused to flow through the first and second passages, heat exchange between them is performed using a metal having high heat conductivity as a medium. It is stated that frost formation can be prevented.

[0006]

However, in the above-mentioned prior art, since heat exchange between two kinds of fluids is performed indirectly using a metal as a medium, the metal is a material having a high thermal conductivity. However, it is difficult to quickly heat the frosted portion. As a result, a problem has been pointed out that the defrosting operation is not efficiently performed, and it is not possible to immediately shift from the defrosting operation to a desired heating operation.

An object of the present invention is to solve such a problem, and an object of the present invention is to provide a vehicle air conditioner capable of performing defrosting work quickly and surely and effectively improving heating performance. And

[0008]

In order to solve the above-mentioned problems, in a vehicle air conditioner according to the present invention, a first heat exchanger for evaporating a heat medium during a heating operation to absorb heat and a heat source are provided. A second heat exchanger for cooling the cooling water whose temperature has been increased by cooling is arranged close to the vehicle length direction.
For this reason, the surrounding temperature of the first heat exchanger is increased via the exhaust heat from the second heat exchanger, and the first heat exchanger can be effectively prevented from being frosted. In addition, the heat medium absorbs waste heat generated around the first heat exchanger as evaporation heat, so that the heating efficiency is greatly improved.

Further, a second heat exchanger is disposed in front of the first heat exchanger in the vehicle length direction, and the first and second heat exchangers are arranged.
A heat exchanger is provided outside the cabin. Therefore, it is possible to effectively prevent water and mud from being applied to the first heat exchanger from the outside, and it is possible to reliably avoid frost and icing of the first heat exchanger. The heat source has a traveling motor and can be effectively applied to an electric vehicle air conditioner.

[0010]

FIG. 1 is a schematic perspective explanatory view of an electric vehicle 12 incorporating a vehicular automatic air conditioner (air conditioner) 10 according to an embodiment of the present invention, and FIG. FIG.

The auto air conditioner 10 has a duct body 14 for blowing air of which temperature and humidity have been adjusted into the vehicle interior, and heat exchange between the air flowing through the duct body 14 and a cooling medium (heat medium). A cooling medium circuit for cooling the air, a heating medium circuit for heating the air by exchanging heat between air flowing through the duct body and hot water, and a heating medium circuit disposed in the duct body; And an air mixing means 20 for performing air mix control of cold air and hot air.

As shown in FIG. 2, the duct main body 14 is disposed on the front side of the vehicle cabin via an instrument panel (not shown). The inside air inlet 24 for introducing the outside air and the outside air inlet 26 for introducing the air outside the vehicle compartment are provided by the switching damper 2.
8 is provided to be freely opened and closed.

The switching damper 2 is provided in the duct body 14.
The blower 30 is disposed adjacent to the side of the blower 30.
An evaporator (indoor heat exchanger) 32 that forms the cooling medium circuit 16 is disposed downstream of the evaporator. Evaporator 32
A heater core 34 constituting the heating medium circuit 18 is provided downstream of the heater core 34, and an air mixing means 20 is mounted on the inlet side of the heater core 34. The air mix means 20 includes an air mix damper 36, and the air mix damper 36 is rotatable via an air mix motor 38 to an arbitrary angle within a range from a position of 0% opening to a position of 100% opening. It is.

Downstream of the duct body 14, a differential outlet 40 for blowing air toward the inner surface of the front windshield of the electric vehicle 12, a face outlet 42 for blowing air toward the head of the occupant, Foot outlet 44 for blowing air toward the feet of the occupant
Are provided. A differential damper 46, a face damper 48, and a foot damper 50 are rotatably attached to the differential outlet 40, the face outlet 42, and the foot outlet 44, respectively.

The evaporator 32 evaporates the cooling medium by exchanging heat between the cooling medium flowing into the inside and the air sent from the blower 30 into the duct body 14, and cools the air. It has a function to do. The cooling medium circuit 16 including the evaporator 32
Is equipped with an electric compressor 52, and an accumulator 5 is connected to a refrigerant line 54a on the low pressure side connecting the suction side of the electric compressor 52 and the outlet side of the evaporator 32.
6 are interposed.

The electric compressor 52 compresses a cooling medium (gas refrigerant) sucked into the inside from the suction port and discharges it as a high-temperature, high-pressure cooling medium from the discharge port side to the refrigerant pipe 54b side. The accumulator 56 separates the cooling medium into a liquid refrigerant and a gas refrigerant, and separates only the gas refrigerant from the electric compressor 5.
2 is provided.

The refrigerant pipe 54b branches at its distal end into refrigerant pipes 54c and 54d.
c branches into refrigerant pipes 54e and 54f. Refrigerant line 54
A first solenoid valve 60 is provided in c, a second solenoid valve 62 is provided in the refrigerant line 54f, and the refrigerant line 54f is connected to the refrigerant line 54a. Refrigerant line 54
e, an outdoor heat exchanger (first heat exchanger) 64 is disposed. The outdoor heat exchanger 64 is blown by a cooling medium in a low-temperature, low-pressure gas-liquid two-phase state and an outdoor fan 66 during a heating operation. The cooling medium has a function of evaporating and evaporating the cooling medium by exchanging heat with the outside air, and a function of exchanging heat between the high-temperature and high-pressure gas refrigerant and the outside air blown by the outdoor fan 66 during the cooling operation to condense and liquefy the gas refrigerant.

A first capillary tube 70 for heating is provided in the refrigerant line 54d.
d and the refrigerant pipe 54e are integrated as a refrigerant pipe 54g and connected to the introduction side of the evaporator 32. A third solenoid valve 68 and a second capillary tube 72 for cooling are arranged in parallel with the refrigerant pipe 54g.

The heating medium circuit 18 has a hot water circulating path 74 for circulating and supplying hot water to the heater core 34. The hot water circulating path 74 includes a water pump 76 and a combustion heater 7.
8 are provided. A part of the hot water circulation path 74 is provided with an outer pipe section 80 having a double pipe structure surrounding the refrigerant pipe 54b of the cooling medium circuit 16 over a predetermined length, and the refrigerant pipe 54b and the outer pipe section 80 are provided. A medium heat exchanger 82 is constituted by the pipe section 80. When the high-temperature, high-pressure cooling medium discharged from the electric compressor 52 and flowing to the refrigerant pipe 54b flows through the refrigerant pipe 54b, the medium heat exchanger 82 includes the hot water as a heating medium passing through the outer pipe 80 of the hot water circulation path 74 and the above-described hot water. It has a function of heating the hot water by exchanging heat with a cooling medium.

The outdoor heat exchanger 64 has a drive system (heat source).
A radiator (second heat exchanger) 92 for cooling the high-temperature cooling water by cooling 90 is provided in parallel. Radiator 9
2 and the outdoor heat exchanger 64 are arranged close to each other in the vehicle length direction of the electric vehicle 12, and the radiator 92.
Is disposed in front of the outdoor heat exchanger 64 in the vehicle length direction (direction of arrow A).

As shown in FIG. 1 and FIG.
Comprises a running motor 94 and a battery 96 for supplying electric energy to the motor 94.
A cooling circuit 98 for circulating and supplying cooling water to the battery 96 is provided. The cooling circuit 98 circulates cooling water along the cooling water circulation path 100 and the cooling water circulation path 100, and supplies the cooling water to the battery storage box 102 that houses the radiator 92, the motor 94, and the battery 96. And a pump 104. The cooling water circulation path 100 has a three-way valve 10 near the radiator 92.
6 has a water channel 108 that branches off.

The thus configured auto air conditioner 10
Will be described below.

First, the operation modes are cooling operation, heating operation,
Table 1 shows the routes of the respective cooling medium circuits 16 in the case of the dehumidifying operation and the air blowing operation.

[0024]

[Table 1]

Therefore, when the operation mode is the heating operation, Table 1
And as shown in FIG. 2, the first and third solenoid valves 60,
68 is closed, and the second solenoid valve 62 is opened. For this reason, the cooling medium discharged from the electric compressor 52 is decompressed from the refrigerant pipes 54b and 54d through the first capillary tube 70 and vaporized through the outdoor heat exchanger 64 in a two-phase airflow state. The refrigerant is circulated from the accumulator 56 to the electric compressor 52 through the two solenoid valves 62 and the refrigerant pipes 54f and 54a.

At this time, in the heating medium circuit 18, the hot water is circulated along the hot water circulation path 74 under the driving action of the water pump 76, and the hot water is supplied to the outer tube 80 constituting the medium heat exchanger 82. Supplied. Therefore, the outer tube portion 80
The hot water in the outer pipe portion 80 is heated by flowing a high-temperature and high-pressure cooling medium through the refrigerant pipe 54b inward. This hot water is introduced into the heater core 34,
The air passing through the heater core 34 is heated to a predetermined temperature.

On the other hand, as shown in FIG.
The motor 94 is driven via electric energy supplied from a battery 96, and a cooling circuit 98 is driven to cool the battery 96 and the motor 94. That is, as shown in FIGS. 1 and 3, the cooling water is circulated along the cooling water circulation path 100 under the driving action of the pump 104. As a result, the cooling water that has cooled the motor 94 and the battery 96 and the like has become high temperature,
Since it passes through the radiator 92 and exchanges heat with external air to be at a low temperature, the motor 94 and the battery 96 can be continuously cooled.

When the heating operation is performed by the automatic air conditioner 10, the cooling medium in the two-phase air flow exchanges heat with the outside air in the outdoor heat exchanger 64, thereby absorbing heat and evaporating. For this reason, the outside air temperature is reduced, and frost is easily caused on the outdoor heat exchanger 64.

However, in the present embodiment, a radiator 92 for cooling the drive system 90 to cool the high-temperature cooling water is provided in front of the outdoor heat exchanger 64 in the vehicle length direction (direction of arrow A). Have been. Accordingly, since the ambient temperature of the outdoor heat exchanger 64 is increased via the exhaust heat from the radiator 92, the effect of reliably preventing the outdoor heat exchanger 64 from forming frost can be obtained.

Moreover, in the outdoor heat exchanger 64, when the cooling medium vaporizes by absorbing heat from the outside air, it becomes possible to absorb the exhaust heat generated around the outdoor heat exchanger 64 as evaporation heat. Thereby, there is an advantage that the heating efficiency in the cooling medium circuit 16 is greatly improved.

Further, a radiator 92 is disposed in front of the outdoor heat exchanger 64 (in the direction of arrow A). Therefore, even when rainwater or the like is sprayed from the front on the traveling electric vehicle 12, it is possible to effectively prevent the outdoor heat exchanger 64 from being exposed to water or mud. Thereby, it is possible to reliably prevent frost and icing from being caused on the outdoor heat exchanger 64, and to greatly reduce the defrosting operation due to frost on the outdoor heat exchanger 64 during the heating operation. Therefore, the advantage that the heating performance can be significantly improved can be obtained.

[0032]

As described above, in the vehicle air conditioner according to the present invention, the cooling water for cooling the heat source is provided in parallel with the first heat exchanger for evaporating the heat medium and absorbing heat during the heating operation. A second heat exchanger for cooling is arranged, and the ambient temperature of the first heat exchanger is increased via waste heat from the second heat exchanger. For this reason, it is possible to effectively prevent the first heat exchanger from frosting, and to absorb the exhaust heat generated around the first heat exchanger as evaporation heat, thereby significantly increasing the heating efficiency. improves.

In addition, since the second heat exchanger is disposed in front of the first heat exchanger in the vehicle length direction, it is possible to prevent the first heat exchanger from being exposed to water or mud from outside. .
Therefore, frost and icing of the first heat exchanger can be reliably avoided.

[Brief description of the drawings]

FIG. 1 is a schematic perspective explanatory view of an electric vehicle incorporating a vehicular auto air conditioner according to an embodiment of the present invention.

FIG. 2 is a schematic diagram illustrating the configuration of the automatic air conditioner.

FIG. 3 is an explanatory diagram of a cooling circuit of a drive system.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Automatic air conditioner 12 ... Electric vehicle 16 ... Cooling medium circuit 18 ... Heating medium circuit 32 ... Evaporator 52 ... Electric compressor 74 ... Hot water circulation path 90 ... Drive system 92 ... Radiator 94 ... Motor 96 ... Battery 100 ... Cooling water circulation path 104 ... pump

Claims (3)

[Claims] 1. A compressor for compressing and sending out a heat medium, and radiating heat by condensing the heat medium discharged from the compressor during a cooling operation, and evaporating the heat medium during a heating operation. A first heat exchanger that absorbs heat, and a second heat exchanger that cools the cooling water having a higher temperature by cooling the heat source, wherein the first and second heat exchangers are mounted on a vehicle. An air conditioner for a vehicle, wherein the air conditioner is arranged in the longitudinal direction and the second heat exchanger is disposed forward of the first heat exchanger in the vehicle length direction. 2. An air conditioner for a vehicle according to claim 1, wherein said first and second heat exchangers are disposed outside a vehicle compartment. 3. An air conditioner according to claim 1, wherein said heat source includes a traveling motor.