JP2001248932A - Air conditioner for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly adjust the quantity of a refrigerant in supplementary heating, in an air conditioner for a vehicle of simple and inexpensive circuit constitution which can perform supplementary heating operation using the hot gas in a refrigerating cycle, in addition to a main heater. SOLUTION: The refrigerant system of an air conditioner for a vehicle, which switches a cooling operation mode for leading the refrigerant sent out of a refrigerant compressor 1 to a condenser 2 and a supplementary heating operation mode for leading it to an evaporator 3 by operating a four-way valve 5, is provided with a first bypass passage 11 which is connected to the refrigerant entry side of the condenser 2, bypassing the four-way valve 5 from the discharge side of the refrigerant compressor 1, the first solenoid valve 12 which is provided in that first bypass passage 11, the second bypass passage 13 which is connected to the suction side of the refrigerant compressor 1, bypassing the first expansion valve 6, the four-way valve 5, and the evaporator 3 from the refrigerant delivery side of the condenser 2, and the second solenoid valve 41 and a check valve 15 which are provided in that second bypass passage 13.

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 mounted on a vehicle such as an automobile, and more particularly to a technique suitable for use in auxiliary heating operation.

[0002]

2. Description of the Related Art Conventionally, a compressor for compressing a low-temperature and low-pressure gas refrigerant to deliver a high-temperature and high-pressure gas refrigerant (hot gas) and a heat for condensing the high-temperature and high-pressure gas refrigerant into a high-temperature and high-pressure liquid refrigerant An exchanger (condenser), a throttling mechanism that decompresses and expands high-temperature and high-pressure liquid refrigerant into low-temperature and low-pressure liquid refrigerant (mist), and heat that evaporates low-temperature and low-pressure liquid refrigerant into low-temperature and low-pressure gas refrigerant 2. Description of the Related Art A vehicle air conditioner using a refrigeration cycle formed by connecting an exchanger (evaporator) with a refrigerant flow path is known. This refrigeration cycle is used as a cooling device for performing cooling and dehumidification in an ordinary vehicle air conditioner. Further, as a heating device, a heat exchanger (heater core) using waste heat of a vehicle traveling engine (internal combustion engine) is generally used. The waste heat in this case utilizes the heat of the engine cooling water, which is heated by cooling the engine and becomes hot water, and is also called a hot water heater.

In such an air conditioner for a vehicle, an evaporator having a cooling capacity for cooling and dehumidifying and a heater core having a heating capacity for heating are provided in a flow path of conditioned air, for example, HVAC (Heating, Ventilation). , and Ai
r-Conditioning)
A cooling operation, a heating operation, a dehumidification heating operation, and the like can be performed by switching a flow path of air to be air-conditioned by a damper or the like. Also, in a heating device using the waste heat of an internal combustion engine,
Since the amount of waste heat tends to decrease with the recent increase in efficiency of engines, it is difficult to obtain sufficient heating capacity, or the temperature of engine cooling water is low immediately after starting operation,
There is a problem that the heating operation cannot be performed until the temperature rises to some extent.

In order to solve the above-mentioned problem, in a conventional vehicle air conditioner using a hot water heater or the like as a main heating device, an electric heater or a combustion heater is used as an auxiliary heating device to supplement the heating capacity of the main heating device. And those utilizing a heat pump or the like are known. In addition, instead of the known technology of such an auxiliary heating device, there is a device that uses a hot gas in a refrigeration cycle, that is, a high-temperature and high-pressure gas refrigerant sent from a refrigerant compressor, by guiding it to an evaporator. As shown, an air conditioner for a vehicle having a simple and inexpensive circuit configuration has been proposed.

[0005] In this circuit configuration, the evaporator 3 connected to the refrigerant circuit 10 and the hot water heater 21 of the main heating device are arranged in series in the HVAC unit 20. The refrigerant circuit 10 includes a refrigerant compressor 1, a condenser 2 connected to a discharge side of the refrigerant compressor, an evaporator 3 connected to a suction side of the refrigerant compressor, and a four-way valve 5. Have been. Each connection port of the four-way valve 5 is connected to the first port 5
a to the discharge side of the refrigerant compressor 1, the second port 5 b to the refrigerant inlet 2 a of the condenser 2, the third port 5 c to the refrigerant outlet 5 c of the condenser 2, and the fourth port 5 d to the evaporator 3.
Respectively connected to the refrigerant inlets 3a. Further, a first throttle mechanism 6 is provided between the refrigerant outlet 2b of the condenser 2 and the third port 5c of the four-way valve 5, and further, between the fourth port 5d of the four-way valve 5 and the refrigerant inlet 3a of the evaporator 3. Is the second
Each of the aperture mechanisms 7 is provided.

In the vehicle air conditioner having such a circuit configuration, the flow path of the refrigerant can be switched by operating the four-way valve 5, and the high-temperature and high-pressure gas refrigerant (hot It is possible to selectively switch between a cooling operation mode in which gas (gas) is introduced to the condenser 2 and an auxiliary heating operation mode in which hot gas sent from the refrigerant compressor 1 is introduced to the evaporator 3. In the cooling operation mode, the flow path in the four-way valve 5 is
Port 5a and second port 5b, and third port 5c and fourth port
The hot gas discharged from the refrigerant compressor 1 communicates with the port 5d, and the hot gas discharged from the refrigerant compressor 1 is supplied to the condenser 2, the four-way valve 5, and the evaporator 3
In order. In the other auxiliary heating mode, as shown by the solid line in the figure, the flow path in the four-way valve 5 includes the first port 5a, the fourth port 5d, and the second port 5d.
b communicates with the third port 5c, and the hot gas delivered from the refrigerant compressor 1 flows to the evaporator 3 by bypassing the condenser 2.

[0007]

However, in the above-mentioned prior art, since the amount of refrigerant cannot be sufficiently adjusted in the auxiliary heating operation mode, there is a possibility that the refrigerant compressor is operated in a gas low or overcharged state. is there. This is because the refrigerant circuit for flowing the hot gas sent from the refrigerant compressor 1 to the evaporator 3 is provided by the second port 5b of the four-way valve 5,
This is because the circuit is completely separated from the closed circuit connecting the capacitor 2 and the third port 5c of the four-way valve 5. Therefore, it has not been possible to adjust the refrigerant capacity by replenishing the refrigerant in the condenser 2 when the gas is low or by moving the refrigerant to the condenser 2 when the gas is overcharged. If the operation of the refrigerant compressor is continued in such a gas-low or overcharged state, the refrigerant compressor itself may be damaged or the compression performance may be reduced. desired.

The present invention has been made in view of the above circumstances, and has as its object to provide a vehicle air conditioner capable of adjusting a refrigerant capacity in an auxiliary heating operation mode.

[0009]

The present invention employs the following means in order to solve the above-mentioned problems. The vehicle air conditioner according to claim 1, further comprising an evaporator and a main heating device connected to a refrigerant system in a flow path of the conditioned air, wherein the refrigerant system includes a refrigerant compressor and a refrigerant compressor. A condenser connected to the discharge side, an evaporator connected to the suction side of the refrigerant compressor, and each connection port is a discharge side of the refrigerant compressor,
A four-way valve connected to a refrigerant inlet of the condenser, a refrigerant outlet of the condenser, and a refrigerant inlet of the evaporator; a first throttle mechanism disposed between the refrigerant outlet of the condenser and the four-way valve; and the four-way valve And a second throttle mechanism disposed between a refrigerant inlet of the evaporator and a cooling operation mode in which the four-way valve is operated to guide refrigerant discharged from the refrigerant compressor to the condenser, and An air conditioner for a vehicle that switches between an auxiliary heating operation mode that guides a refrigerant delivered from a refrigerant compressor to an evaporator, and that bypasses the four-way valve from a discharge side of the refrigerant compressor to the refrigerant system. A first bypass flow path connected to the refrigerant inlet side of the condenser, a first opening / closing valve provided in the first bypass flow path, A second bypass passage connected to the suction side of the refrigerant compressor bypassing the first throttle mechanism, the four-way valve and the evaporator, and a second opening / closing provided in the second bypass passage A valve and a check valve are provided.

According to such a vehicle air conditioner,
If the first and second on-off valves and the second on-off valve are opened to make both the first bypass flow path and the second bypass flow path in communication, the refrigerant in the condenser is expelled to the evaporator side for replenishment. Further, if the first on-off valve is opened to open the first bypass flow path, excess refrigerant can be moved into the condenser.

[0011] The vehicle air conditioner according to claim 2 is
An evaporator and a main heating device connected to a refrigerant system are provided in a flow path of the conditioned air, and the refrigerant system includes a refrigerant compressor, a condenser connected to a discharge side of the refrigerant compressor, and the refrigerant compressor An evaporator connected to the suction side of the refrigerant compressor, a four-way valve having each connection port connected to a discharge side of the refrigerant compressor, a refrigerant inlet of the condenser, a refrigerant outlet of the condenser, and a refrigerant inlet of the evaporator, and the four-way valve And an electronic expansion valve disposed between a refrigerant inlet of the evaporator and a cooling operation mode in which the four-way valve is operated to guide refrigerant discharged from the refrigerant compressor to the condenser.
An air conditioner for a vehicle that switches between an auxiliary heating operation mode that guides a refrigerant delivered from the refrigerant compressor to the evaporator and that bypasses the four-way valve from a discharge side of the refrigerant compressor to the refrigerant system. A first bypass flow path connected to the refrigerant inlet side of the condenser, a first on-off valve provided in the first bypass flow path, and the four-way valve and the evaporator from the refrigerant outlet side of the condenser. A second bypass compressor connected to the suction side of the refrigerant compressor.
, And a second on-off valve and a check valve provided in the second bypass flow path.

According to such a vehicle air conditioner,
If the first and second on-off valves and the second on-off valve are opened to make both the first bypass flow path and the second bypass flow path in communication, the refrigerant in the condenser is expelled to the evaporator side for replenishment. Further, if the first on-off valve is opened to open the first bypass flow path, excess refrigerant can be moved into the condenser.

In the air conditioner for a vehicle according to the first and second aspects, when the suction pressure of the refrigerant compressor becomes lower than a predetermined value, the first on-off valve and the second on-off valve are turned off.
It is preferable to control the on-off valve to open for a predetermined time,
As a result, the hot gas is supplied to the condenser through the first bypass passage when the gas is low, so that the refrigerant accumulated in the condenser is expelled and the evaporator passes through the second bypass passage. Replenished to the side. Accordingly, the gas low state can be eliminated by this replenishment. Further, in the air conditioner for a vehicle according to the first and second aspects, when the discharge pressure of the refrigerant compressor becomes a high pressure equal to or higher than a predetermined value, control is performed to open the first on-off valve. This allows hot gas to flow to the condenser through the first bypass flow path at the time of overcharging. Further, since the refrigerant outlet side of the condenser is closed, excess refrigerant is introduced into the condenser. You can move and stay. Therefore,
By moving the excess refrigerant into the condenser, the amount of the refrigerant is adjusted to an appropriate amount, and an overcharged state can be eliminated.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a vehicle air conditioner according to the present invention will be described with reference to the drawings. FIG.
In the first embodiment shown in FIG. 1, reference numeral 1 denotes a refrigerant compressor, 2 denotes a condenser, 3 denotes an evaporator, 4 denotes an accumulator, 5 denotes a four-way valve, 6 denotes a first expansion valve, and 7 denotes a second expansion valve. The refrigerant circuit 10A of the refrigeration cycle in which the refrigerant changes its state and circulates is formed by connecting these devices with the refrigerant pipe 8. In this embodiment, an engine E for driving a vehicle is used as a drive source of the refrigerant compressor 1, and a hot water heater (heater core) 21 using waste heat of the engine E is used as a main heating device.

The refrigerant compressor 1 compresses a low-temperature and low-pressure gas refrigerant and sends out a high-temperature and high-pressure gas refrigerant (hot gas). The refrigerant compressor 1 is connected to an output shaft of the engine E via a belt 22 and an electromagnetic clutch 23. ing. The discharge side of the refrigerant compressor 1 is connected to a first port 5 a of the four-way valve 5 by a refrigerant pipe 8. The second port 5b and the third port 5c of the four-way valve 5 are connected to the refrigerant inlet 2a and the refrigerant outlet 2b of the condenser 2 by a refrigerant pipe 8, respectively. The condenser 2 has a function of condensing a high-temperature and high-pressure gas refrigerant supplied from the refrigerant compressor 1 by heat exchange with air and sending it out as a high-temperature and high-pressure liquid refrigerant. Reference numeral 9 in the drawing indicates a condenser fan.

A fourth port 5d of the four-way valve 5 is connected to a refrigerant inlet 3a of the evaporator 3 by a refrigerant pipe 8. The evaporator 3 includes a condenser 2 and a first expansion valve 6 provided as a throttle mechanism during a normal cooling operation.
And a function of receiving the supply of the low-temperature and low-pressure liquid refrigerant that has passed through the second expansion valve 7, vaporizing the liquid refrigerant by heat exchange with the conditioned air, and sending it out as a low-temperature and low-pressure gas refrigerant. As a result, the conditioned air passing through the evaporator 3 is deprived of the heat of vaporization and cooled, so that the cooling and dehumidifying effects of the conditioned air can be obtained. The refrigerant outlet 3b of the evaporator 3
Is connected to the suction side of the refrigerant compressor 1 by a refrigerant pipe 8, and an accumulator 4 is installed in the refrigerant pipe 8 to adjust the amount of refrigerant and separate gas and liquid.

The refrigerant circuit 10A thus configured is
By switching the four-way valve 5, it is possible to switch between a normal cooling operation mode (broken line display) and an auxiliary heating operation mode (solid line display). In the cooling operation mode, the flow path of the refrigerant passing through the four-way valve 5 is between the first port 5a and the second port 5b and the third port 5 as indicated by broken lines.
Since the connection between c and the fourth port 5d is respectively made, the high-temperature and high-pressure gas refrigerant sent from the refrigerant compressor 1 is guided to the condenser 2. On the other hand, in the auxiliary heating operation mode, the flow path of the refrigerant passing through the four-way valve 5 is between the first port 5a and the fourth port 5d and between the second port 5b and the third port 5d as indicated by solid lines. The connection with the port 5c changes to a connected state. Therefore, the high-temperature and high-pressure gas refrigerant sent from the refrigerant compressor 1 is guided to the evaporator 3 without passing through the condenser 2. The high-temperature and high-pressure gas refrigerant (hot gas) introduced into the evaporator 3 heats by exchanging heat with the conditioned air, so that the evaporator 3 in this case functions as an auxiliary heating device.

In the illustrated embodiment, the refrigerant outlet 2b of the condenser 2 and the third port 5c of the four-way valve 5 are provided.
A first expansion valve 6 is provided as a first throttle mechanism in a refrigerant pipe 8 that connects between the refrigerant pipe 8 and a refrigerant pipe that connects between a fourth port 5 d of the four-way valve 5 and a refrigerant inlet 3 a of the evaporator 3. 8, a second expansion valve 7 is provided as a second throttle mechanism. Although a fixed throttle is used for the first expansion valve 6 and the second expansion valve 7, a variable throttle can also be used. The first expansion valve 6 allows the high-temperature and high-pressure liquid refrigerant delivered from the condenser 2 to pass in the cooling operation mode. Therefore, the first expansion valve 6 causes the high-temperature and high-pressure liquid refrigerant to expand under reduced pressure, and the low-temperature and low-pressure liquid refrigerant (fog) to expand.
The throttle opening degree set so as to be transmitted as is used. The first expansion valve 6 in the cooling operation mode is
Since it is in a state of being arranged in series with a second expansion valve 7, which will be described later, it is only necessary to set both so as to cooperate to exhibit a desired function. The second expansion valve 7 is provided mainly for the purpose of reducing the pressure of the high-temperature and high-pressure gas refrigerant (hot gas) sent from the refrigerant compressor 1 in the auxiliary heating operation mode. Therefore, the second expansion valve 7 has a throttle opening set to reduce the hot gas to a predetermined pressure. That is, since the low-temperature and low-pressure liquid refrigerant is supplied in the normal cooling operation, the refrigerant has a function of limiting and protecting the refrigerant pressure acting on the evaporator 3 not designed to have a high pressure resistance.

A first bypass flow path 11 connected to the refrigerant inlet 2a of the condenser 2 is provided from the discharge side of the refrigerant compressor 1 bypassing the four-way valve 5, and the first bypass flow path 11 is connected to the first bypass flow path 11. Has a first solenoid valve 12 as a first on-off valve. Further, a second bypass flow path 13 connected to the suction side of the refrigerant compressor 1 from the refrigerant outlet 2b side of the condenser 2 by bypassing the four-way valve 5, the first expansion valve 6, the second expansion valve 7, and the evaporator 3 The second bypass flow path 13 is provided with a second solenoid valve 14 and a check valve 15 as a second on-off valve. The check valve 15 is provided for the purpose of preventing hot gas flowing out of the evaporator 3 from flowing back to the second solenoid valve 14 and the condenser 2 in the auxiliary heating operation mode. First solenoid valve 12 described above
The second solenoid valve 14 is connected to the control unit 16 and controlled to open and close, but is normally in a closed state. The control unit 16 is connected to a suction pressure sensor 17 for detecting a suction pressure of the refrigerant compressor 1 and a discharge pressure sensor 18 for detecting a discharge pressure of the refrigerant compressor 1. Monitoring.

The above-described evaporator 3 is arranged in series with the hot water heater 21 in the HVAC unit 20 on the upstream side in the flow direction of the conditioned air. The HVAC unit 20 includes, in addition to the evaporator 3, the hot water heater 21, and the blower 24, an inside / outside air switching damper (not shown), an air mix damper, and a damper that selectively switches an air-conditioning air outlet according to various blowing modes. It has a kind. The hot water heater 21 is connected to an engine cooling water system of the engine E through a hot water pipe 25, and an opening / closing valve 26 is provided at an appropriate position of the hot water pipe 25. The on-off valve 26 is opened when heating such as a heating operation is required. The on-off valve 26 shunts engine cooling water, which has become high temperature by cooling the engine E, and introduces it into the hot water heater 21. The engine cooling water thus guided to the hot water heater 21 is heated by exchanging heat with the conditioned air passing through the hot water heater 21, and then returned to the engine cooling water system again.

According to the vehicle air conditioner having the above-described configuration, a normal cooling operation mode in which hot gas is guided to the condenser 2 and an auxiliary heating mode in which hot gas is guided to the evaporator and used as a heating device for auxiliary heating. Can be switched only by operating the four-way valve 5. Then, in the auxiliary heating operation mode, when the suction pressure sensor 17 detects a low pressure equal to or lower than a predetermined value, that is, when it is determined that the gas is in the gas low state, the control unit 16 controls the first solenoid valve 12 and the second solenoid valve 14 to operate. Open. As a result, the hot gas sent from the refrigerant compressor 1 also flows to the condenser 2 through the first bypass 11, so that the refrigerant in the condenser 2 is heated and vaporized, The refrigerant merges into the suction side of the refrigerant compressor 1 through the flow path 13. Therefore, by continuing such an operation for a predetermined time, the refrigerant amount is replenished, the gas-low state is eliminated, and the auxiliary heating operation with the appropriate refrigerant amount can be performed.

In the auxiliary heating operation mode, when the discharge pressure sensor 18 detects a high pressure higher than a predetermined value, that is, when it is determined that the battery is overcharged, the control unit 16 opens only the first solenoid valve 12. And As a result, the hot gas delivered from the refrigerant compressor 1 also flows to the condenser 2 through the first bypass 11, but the second bypass passage 13 is closed by the second solenoid valve 14. Therefore, the refrigerant is accumulated in the condenser 2. Therefore, by continuing such an operation, the amount of refrigerant compressed by the refrigerant compressor 1 is reduced, the overcharged state is eliminated, and the auxiliary heating operation with the appropriate refrigerant amount can be performed.

Next, a second embodiment of the present invention will be described with reference to FIG. This embodiment differs from the above-described first embodiment in that an electric refrigerant compressor 1A driven by an electric motor M is employed, and an electronic expansion valve 7A is employed as a throttle mechanism. Since other basic configurations are substantially the same, they are denoted by the same reference numerals as in FIG. 1 and detailed description thereof is omitted. In the illustrated example, as the refrigerant compressor 1A, a so-called hermetic type having an electric motor M built in a casing is used instead of the engine E for driving the vehicle as a drive source.
The electric motor M includes a control unit 16 and an inverter control unit 19
Thus, the rotation speed is variable by inverter control, and accordingly, the operation (rotation) speed of the refrigerant compressor 1A driven by the inverter and the compressor capacity related thereto are also variable.

The electronic expansion valve 7A is a fourth
It is installed in a refrigerant pipe 8 that connects the port 5d and the refrigerant inlet 3a of the evaporator 3. The electronic expansion valve 7A is a throttle mechanism that can variably control the throttle opening in accordance with a pulse signal input from the control unit 16, and can be used for a wide range of refrigerants from high-temperature and high-pressure liquid refrigerant to high-temperature and high-pressure gas refrigerant. . Therefore, the single electronic expansion valve 7A can cope with both the cooling operation mode and the auxiliary heating operation mode.
The first expansion valve 6 installed between the refrigerant outlet 2a and the third port 5c of the four-way valve 5 can be eliminated and eliminated.

As described above, even if the refrigerant compressor 1A or the electronic expansion valve 7A driven by the inverter-controlled electric motor M is employed, the refrigerant circuit 10B has a simple and small number of parts, and the hot gas is supplied to the condenser 2A. The operation switching between the normal cooling operation mode for guiding to the evaporator and the auxiliary heating mode for guiding the hot gas to the evaporator and using it as a heating device for auxiliary heating can be performed only by operating the four-way valve 5. Further, by using the inverter-controlled refrigerant compressor 1A, the refrigerant capacity itself discharged from the compressor can be finely controlled, and the electronic expansion valve 7A is connected to the fourth port 5d of the four-way valve 5.
And the refrigerant inlet 3a of the evaporator 3, the hot gas can be supplied to the evaporator 3 after the pressure is reduced during the auxiliary heating operation. Therefore, the pressure-resistant design of the evaporator 3 is reduced to a conventionally low value. Can be set.

In the vehicle air conditioner 10B having such a configuration, the first bypass passage 11, the first
Solenoid valve 12, second bypass flow path 13, second solenoid valve 14
In addition, since the check valve 15 is provided, the auxiliary heating operation can be performed by returning the refrigerant amount in the gas low state or the overcharge state to an appropriate amount in the same manner as in the first embodiment.

The electronic expansion valve 7A can be applied to the first embodiment and combined with the refrigerant compressor 1 using the engine E as a driving source. Alternatively, the first expansion valve 6 and the second expansion valve 7 having a fixed throttle can be applied instead of the electronic expansion valve 7A. The electric motor M according to the second embodiment does not necessarily need to be inverter-controlled, and the refrigerant compressor 1A is not limited to a hermetic type in which the electric motor M is built in a casing. May be driven by the electric motor.

In the above embodiment, the main heating device is the hot water heater 21. However, in the above-described present invention, the vehicle air conditioner using another heating device such as an electric heater or a combustion heater as the main heating device. It is needless to say that the present invention can be applied not only to the HVAC unit 20 having a configuration in which the main heating device and the evaporator 3 are arranged in a horizontal direction but also to a configuration in which the main heating device and the evaporator 3 are arranged vertically. Nor.

[0029]

According to the air conditioner for a vehicle of the present invention described above, a simple cooling operation mode and an auxiliary heating operation mode can be selectively switched by the switching operation of the refrigerant flow path by the four-way valve. As a circuit configuration, the heating capacity can be improved by effectively using the hot gas of the refrigerant circuit for auxiliary heating, and the gas low state and overcharge state during auxiliary heating can be easily eliminated by operating the on-off valve can do. Therefore, by properly maintaining the refrigerant amount during the auxiliary heating operation, it is possible to prevent the refrigerant compressor itself from being damaged, and to prevent a decrease in compression performance. It has an excellent effect of improving the durability and reliability of the provided air conditioner for a vehicle.

[Brief description of the drawings]

FIG. 1 is a diagram showing one embodiment of a vehicle air conditioner according to the present invention, and is a system diagram showing a first embodiment.

FIG. 2 is a view showing one embodiment of a vehicle air conditioner according to the present invention, and is a system diagram showing a second embodiment.

FIG. 3 is a system diagram showing a configuration example of a conventional vehicle air conditioner.

[Explanation of symbols]

 1, 1A refrigerant compressor 2 condenser 3 evaporator 4 accumulator 5 four-way valve 6 first expansion valve (first throttle mechanism) 7 second expansion valve (second throttle mechanism) 7A electronic expansion valve 8 refrigerant pipe 10A, 10B refrigerant Circuit 11 First bypass flow path 12 First solenoid valve (first open / close valve) 13 Second bypass flow path 14 Second solenoid valve (second open / close valve) 15 Check valve 16 Control unit 17 Suction pressure sensor 18 Discharge pressure sensor 19 Inverter control unit 20 HVAC unit 21 Hot water heater (main heating device) E Engine M Electric motor

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kiyoto Yasui 3-1-1 Asahicho, Nishibiwajima-cho, Nishi-Kasugai-gun, Aichi Prefecture Inside the Air Conditioning Works of Mitsubishi Heavy Industries, Ltd. (72) Inventor Tomoyasu Adachi Tomoyasu Adachi 3-1 Asahicho Mitsubishi Heavy Industries, Ltd. Air Conditioner Works F-term (reference) 3L092 AA07 AA13 BA05 BA27 DA01 DA14 EA03 EA05 EA18 FA23

Claims (4)

[Claims] 1. An evaporator and a main heating device connected to a refrigerant system are provided in a flow path of air-conditioned air, and the refrigerant system comprises:
A refrigerant compressor, a condenser connected to a discharge side of the refrigerant compressor, an evaporator connected to a suction side of the refrigerant compressor, and each connection port is a discharge side of the refrigerant compressor, a refrigerant inlet of the condenser. A four-way valve connected to a refrigerant outlet of the condenser and a refrigerant inlet of the evaporator; a first throttle mechanism disposed between the refrigerant outlet of the condenser and the four-way valve; and a refrigerant of the four-way valve and the evaporator. And a second throttle mechanism disposed between the refrigerant compressor and a cooling operation mode in which the four-way valve is operated to guide the refrigerant discharged from the refrigerant compressor to the condenser. An air conditioning apparatus for a vehicle that switches between an auxiliary heating operation mode and an auxiliary heating operation mode in which refrigerant is guided to the evaporator, wherein the four-way valve is bypassed to the refrigerant system from a discharge side of the refrigerant compressor. A first bypass flow path connected to the refrigerant inlet side of the condenser, a first on-off valve provided in the first bypass flow path, and the first throttle from a refrigerant outlet side of the condenser. A second bypass passage connected to the suction side of the refrigerant compressor, bypassing the mechanism, the four-way valve and the evaporator, a second on-off valve provided in the second bypass passage, and a check valve An air conditioner for a vehicle, comprising a valve. 2. An evaporator and a main heating device connected to a refrigerant system are provided in a flow path of conditioned air, and the refrigerant system has
A refrigerant compressor, a condenser connected to a discharge side of the refrigerant compressor, an evaporator connected to a suction side of the refrigerant compressor, and each connection port is a discharge side of the refrigerant compressor, a refrigerant inlet of the condenser. A refrigerant outlet of the condenser, and a four-way valve connected to the refrigerant inlet of the evaporator, and an electronic expansion valve disposed between the four-way valve and the refrigerant inlet of the evaporator, operating the four-way valve An air conditioner for a vehicle that switches between a cooling operation mode that guides a refrigerant delivered from the refrigerant compressor to the condenser and an auxiliary heating operation mode that guides a refrigerant delivered from the refrigerant compressor to the evaporator, A first bypass flow path connected to a refrigerant inlet side of the condenser by bypassing the four-way valve from a discharge side of the refrigerant compressor to the refrigerant system; A first on-off valve provided in the bypass flow path, a second bypass flow path connected to the suction side of the refrigerant compressor by bypassing the four-way valve and the evaporator from the refrigerant outlet side of the condenser, An air conditioner for a vehicle, comprising a second on-off valve and a check valve provided in the second bypass flow path. 3. The control device according to claim 1, wherein when the suction pressure of the refrigerant compressor becomes lower than a predetermined value, the first and second on-off valves are controlled to open for a predetermined time. Item 3. The air conditioner for vehicles according to Item 1 or 2. 4. The vehicle air according to claim 1, wherein when the discharge pressure of the refrigerant compressor becomes higher than a predetermined value, the first on-off valve is controlled to open. Harmony equipment.