WO2017146267A1

WO2017146267A1 - Air-conditioning device for vehicle

Info

Publication number: WO2017146267A1
Application number: PCT/JP2017/008040
Authority: WO
Inventors: 鈴木　謙一; 竜宮腰; 耕平山下
Original assignee: サンデン・オートモーティブクライメイトシステム株式会社
Priority date: 2016-02-26
Filing date: 2017-02-21
Publication date: 2017-08-31
Also published as: JP6738156B2; JP2017149364A

Abstract

Provided is an air-conditioning device for vehicle, comprising an opening/closing valve and a bypass pipe that bypasses a radiator and an outdoor expansion valve, wherein the noise generated when opening the opening/closing valve when switching between heating mode and dehumidifying heating mode is reduced or eliminated. Two modes are executed: a heating mode in which solenoid valve (30) is opened and solenoid valve (40) is closed, and a dehumidifying heating mode in which the solenoid valve (30) is closed and the solenoid valve (40) is opened and heat is dissipated from the coolant in an outdoor heat exchanger (7), heat is absorbed by a heat sink (9), and an auxiliary heater (23) is made to generate heat. When switching from heating mode to dehumidifying heating mode, after reducing the pressure differential before and after the solenoid valve (40), control is performed to reduce the noise level associated with the opening of the solenoid valve (40) and the closing of the solenoid valve (30).

Description

Air conditioner for vehicles

The present invention relates to a heat pump type air conditioner that air-conditions the interior of a vehicle, and more particularly to an air conditioner that can be applied to a hybrid vehicle or an electric vehicle.

Recently, hybrid vehicles and electric vehicles have become popular due to the emergence of environmental problems. As an air conditioner that can be applied to such a vehicle, a compressor that compresses and discharges the refrigerant, an internal condenser that is provided on the vehicle interior side and dissipates the refrigerant, and is provided on the vehicle interior side. An evaporator that absorbs the refrigerant, an external condenser that dissipates or absorbs heat from the passenger compartment, a first expansion valve that expands the refrigerant that flows into the external condenser, and a refrigerant that flows into the evaporator A second expansion valve for expanding the internal combustion engine, piping for bypassing the internal condenser and the first expansion valve, and flowing the refrigerant discharged from the compressor to the internal condenser or bypassing the internal condenser and the first expansion valve A first valve that switches between direct flow from the pipe to the external condenser, the refrigerant discharged from the compressor is caused to flow through the internal condenser by the first valve to dissipate the heat, and the discharged refrigerant is passed through the first expansion valve. After heating, the refrigerant discharged from the compressor is radiated in the internal condenser by the first valve, the radiated refrigerant is depressurized by the second expansion valve, and the refrigerant absorbs heat in the evaporator. The dehumidification mode to be performed, and the refrigerant discharged from the compressor bypasses the internal condenser and the first expansion valve by the first valve and flows to the external condenser to radiate heat, and after the pressure is reduced by the second expansion valve, A device that switches and executes a cooling mode for absorbing heat has been developed (see, for example, Patent Document 1).

JP2013-23210A JP 2014-88151 A

Here, when the first valve of Patent Document 1 is configured with two on-off valves provided in each refrigerant pipe branched from the discharge side of the compressor, when switching between the heating mode, the dehumidifying mode, and the cooling mode, One of the on-off valves is opened and the other is closed. However, since the pressure difference before and after these on-off valves is large, there is a problem that a relatively large noise is generated by the refrigerant that flows suddenly to the on-off valves that are opened.
Here, when switching between heating and cooling, there has been proposed one that suppresses the generation of abnormal noise by lowering the pressure difference between the high pressure side and the low pressure side of the refrigerant circuit and then opening the on-off valve (for example, Patent Documents). 2).
The present invention has been made to solve the conventional technical problems, and is equipped with a bypass pipe that bypasses a radiator and an outdoor expansion valve, and an air conditioner for a vehicle that includes an on-off valve for switching a flow path. An object of the present invention is to eliminate or reduce noise generated when the on-off valve is opened when switching between the heating mode and the dehumidifying heating mode, and a decrease in the blowing temperature.

An air conditioner for a vehicle according to a first aspect of the present invention includes a compressor that compresses a refrigerant, an air flow passage through which air supplied to the vehicle interior flows, and air that radiates the refrigerant and supplies the refrigerant to the vehicle interior from the air flow passage. A heat sink for heating the air, a heat absorber for absorbing the refrigerant to cool the air supplied from the air flow passage to the vehicle interior, an outdoor heat exchanger provided outside the vehicle interior, and the radiator An outdoor expansion valve for decompressing the refrigerant flowing into the outdoor heat exchanger, a first on-off valve provided between the discharge side of the compressor and the inlet side of the radiator, and upstream of the first on-off valve A bypass pipe for passing the refrigerant discharged from the compressor bypassing the radiator and the outdoor expansion valve to the outdoor heat exchanger, a second on-off valve provided in the bypass pipe, and air An auxiliary heating device for heating the air supplied from the flow passage to the vehicle interior; And a control device that opens the first on-off valve and closes the second on-off valve to allow the refrigerant discharged from the compressor to flow through the radiator to dissipate the heat and to dissipate the released refrigerant. After the pressure is reduced by the expansion valve, the heating mode in which heat is absorbed by the outdoor heat exchanger, the outdoor expansion valve is fully closed, the first on-off valve is closed, and the second on-off valve is opened. This is performed by switching the dehumidifying and heating mode in which the auxiliary heating device generates heat while the refrigerant is depressurized after flowing through the outdoor heat exchanger through the bypass pipe, and the radiated refrigerant is decompressed and then absorbed by the heat absorber. When the control device switches from the heating mode to the dehumidifying heating mode, after reducing the pressure difference before and after the second on-off valve, the control device opens the second on-off valve, closes the first on-off valve, and closes the outdoor expansion valve. Execute noise improvement control with fully closed And wherein the Rukoto.
The vehicle air conditioner according to a second aspect of the present invention is the vehicle air conditioner according to the second aspect of the present invention, wherein in the noise improvement control, the control device increases the valve opening of the outdoor expansion valve and controls the rotational speed of the compressor. When the pressure difference before and after the on / off valve is reduced and the pressure difference falls below a predetermined value, the second on / off valve is opened, the first on / off valve is closed, and the outdoor expansion valve is fully closed. It is characterized by.
According to a third aspect of the present invention, there is provided a vehicular air conditioner according to the first aspect of the present invention, wherein the control device is configured to fully open the outdoor expansion valve and set the rotational speed of the compressor to a low value in the noise improvement control. Thus, when the pressure difference before and after the second on-off valve is reduced and the pressure difference becomes equal to or less than the predetermined value, or after the predetermined time has elapsed since the rotation speed of the compressor is reduced to the low value, the second on-off valve Is opened, the first on-off valve is closed, and the outdoor expansion valve is fully closed.
The vehicle air conditioner according to a fourth aspect of the present invention is the air conditioning apparatus for a vehicle according to the second or third aspect, wherein when the control device switches from the heating mode to the dehumidifying heating mode, the auxiliary heating device generates heat and the temperature of the auxiliary heating device is increased. When the value becomes equal to or greater than a predetermined value, the refrigerant is switched to a state in which the refrigerant discharged from the outdoor heat exchanger flows to the heat absorber, and the control of the outdoor expansion valve and the compressor in the noise improvement control is started.
A vehicle air conditioner according to a fifth aspect of the present invention includes a compressor that compresses a refrigerant, an air flow passage through which air supplied to the vehicle interior flows, and air that radiates the refrigerant and supplies the refrigerant from the air flow passage to the vehicle interior. A heat sink for heating the air, a heat absorber for absorbing the refrigerant to cool the air supplied from the air flow passage to the vehicle interior, an outdoor heat exchanger provided outside the vehicle interior, and the radiator An outdoor expansion valve for decompressing the refrigerant flowing into the outdoor heat exchanger, a first on-off valve provided between the discharge side of the compressor and the inlet side of the radiator, and upstream of the first on-off valve A bypass pipe for passing the refrigerant discharged from the compressor bypassing the radiator and the outdoor expansion valve to the outdoor heat exchanger, a second on-off valve provided in the bypass pipe, and air An auxiliary heating device for heating the air supplied from the flow passage to the vehicle interior; And a control device that opens the first on-off valve and closes the second on-off valve to allow the refrigerant discharged from the compressor to flow through the radiator to dissipate the heat and to dissipate the released refrigerant. After the pressure is reduced by the expansion valve, the heating mode in which heat is absorbed by the outdoor heat exchanger, the outdoor expansion valve is fully closed, the first on-off valve is closed, and the second on-off valve is opened. This is performed by switching the dehumidifying and heating mode in which the auxiliary heating device generates heat while the refrigerant is depressurized after flowing through the outdoor heat exchanger through the bypass pipe, and the radiated refrigerant is decompressed and then absorbed by the heat absorber. When the control device switches from the dehumidifying / heating mode to the heating mode, the control device reduces the pressure difference before and after the first on-off valve, then opens the first on-off valve and closes the second on-off valve. It is characterized by performing.
According to a sixth aspect of the present invention, in the vehicle air conditioner according to the sixth aspect of the present invention, the control device opens the outdoor expansion valve and controls the rotational speed of the compressor or stops the compressor in the noise improvement control. Thus, the pressure difference before and after the first on-off valve is reduced, and when the pressure difference becomes a predetermined value or less, the first on-off valve is opened and the second on-off valve is closed.
According to a seventh aspect of the present invention, there is provided a vehicle air conditioner according to the fifth aspect of the present invention, wherein the control device is configured to control the outdoor expansion valve in the heating mode and stop the compressor in the noise improvement control. When the pressure difference before and after the on / off valve is reduced and the pressure difference becomes a predetermined value or less, or after a predetermined time has elapsed since the compressor was stopped, the first on / off valve is opened. It is characterized by closing.
In addition to the inventions of claims 5 to 7, the vehicle air conditioner of the invention of claim 8 opens in the heating mode and causes the refrigerant drawn from the outdoor heat exchanger to be sucked into the compressor. In the dehumidifying and heating mode, a third opening / closing valve is provided to close the refrigerant that flows out of the outdoor heat exchanger and flows into the heat absorber, and the control device opens the first opening / closing valve in the noise improvement control. The third on-off valve is opened when the pressure difference before and after the third on-off valve becomes a predetermined value or less after the on-off valve is closed.
According to a ninth aspect of the present invention, in the vehicle air conditioner according to the ninth aspect of the present invention, in the noise improvement control, the control device increases heat generation of the auxiliary heating device, opens the third on-off valve, and then generates heat of the auxiliary heating device. It is characterized by lowering.
According to a tenth aspect of the present invention, there is provided an air conditioning apparatus for a vehicle according to the present invention, wherein the control device reduces the heat generation of the auxiliary heating device when the high pressure side pressure becomes a predetermined value or higher after opening the third on-off valve. It is characterized by making it.

According to the first aspect of the present invention, the compressor for compressing the refrigerant, the air flow passage through which the air supplied to the vehicle interior flows, and the air supplied to the vehicle interior from the air flow passage by radiating the refrigerant are heated. Radiator, a heat absorber for absorbing the refrigerant to cool the air supplied from the air flow passage to the vehicle interior, an outdoor heat exchanger provided outside the vehicle compartment, and an outdoor heat exchanger exiting the radiator An outdoor expansion valve for depressurizing the refrigerant flowing into the compressor, a first on-off valve provided between the discharge side of the compressor and the inlet side of the radiator, and a branch on the upstream side of the first on-off valve. A bypass pipe for bypassing the radiator and the outdoor expansion valve and allowing the refrigerant discharged from the compressor to flow to the outdoor heat exchanger, a second on-off valve provided in the bypass pipe, and an air flow passage from the vehicle Auxiliary heating device for heating the air supplied to the room and a control device By this control device, the first on-off valve is opened and the second on-off valve is closed, whereby the refrigerant discharged from the compressor is caused to flow through the radiator to dissipate the heat, and the radiated refrigerant is decompressed by the outdoor expansion valve. After that, the heating mode in which heat is absorbed by the outdoor heat exchanger, the outdoor expansion valve is fully closed, the first on-off valve is closed, and the second on-off valve is opened to bypass the refrigerant discharged from the compressor. In the vehicle air conditioner that performs switching by switching the dehumidifying heating mode for causing the auxiliary heating device to generate heat while depressurizing the refrigerant that has been radiated to the outdoor heat exchanger and depressurizing the radiated refrigerant, When the device switches from the heating mode to the dehumidifying heating mode, after reducing the pressure difference before and after the second on-off valve, the second on-off valve is opened, the first on-off valve is closed, and the outdoor expansion valve is fully closed. Execute noise improvement control When switching from the heating mode to the dehumidifying heating mode, when the second on-off valve is opened, drastic suppression or elimination of the sudden flow of refrigerant toward the outdoor heat exchanger when the second on-off valve is opened can do. Thereby, at the time of switching from the heating mode to the dehumidifying heating mode, noise generated when the second on-off valve is opened can be eliminated or reduced.
In this case, in the noise improvement control, the control device as in the second aspect of the invention expands the valve opening of the outdoor expansion valve and controls the rotational speed of the compressor to control the pressure before and after the second on-off valve. If the difference is reduced and the pressure difference becomes equal to or less than a predetermined value, the second on-off valve is opened, the first on-off valve is closed, and the outdoor expansion valve is fully closed. By increasing the valve opening degree, the pressure on the refrigerant downstream side of the second on-off valve is increased, and by reducing the pressure on the refrigerant upstream side of the second on-off valve by controlling the rotation speed of the compressor, before and after the second on-off valve It is possible to effectively reduce the pressure difference, to quickly switch to the dehumidifying heating mode, and to effectively eliminate or reduce noise generated at the time of switching.
According to the third aspect of the present invention, in the noise improvement control, the control device fully opens the outdoor expansion valve and sets the rotation speed of the compressor to a predetermined low value so that the pressure before and after the second on-off valve is reduced. When the difference is reduced and the pressure difference becomes equal to or less than the predetermined value, or after the predetermined time has elapsed since the rotation speed of the compressor is reduced to the low value, the second on-off valve is opened and the first on-off valve is closed. Even if the outdoor expansion valve is fully closed, the pressure on the refrigerant downstream side of the second on-off valve is increased by fully opening the outdoor expansion valve, and the refrigerant upstream side of the second on-off valve is reduced by reducing the rotational speed of the compressor. The pressure difference before and after the second on-off valve can be quickly reduced by reducing the pressure of the gas, so that the dehumidifying / heating mode can be accurately switched, and noise generated at the time of switching can be effectively eliminated or reduced. Become.
In these, when the control device switches from the heating mode to the dehumidifying heating mode as in the invention of the fourth aspect, the auxiliary heating device generates heat, and the outdoor heat exchange is performed when the temperature of the auxiliary heating device becomes a predetermined value or more. If the refrigerant discharged from the cooler is switched to the state where it flows to the heat absorber, and the control of the outdoor expansion valve and the compressor in the noise improvement control is started, the temperature of the blowout temperature is reduced when switching from the heating mode to the dehumidifying heating mode. Can also be suppressed.
According to the invention of claim 5, the compressor for compressing the refrigerant, the air flow passage through which the air supplied to the vehicle interior flows, and the air supplied to the vehicle interior from the air flow passage by radiating the refrigerant are heated. Radiator, a heat absorber for absorbing the refrigerant to cool the air supplied from the air flow passage to the vehicle interior, an outdoor heat exchanger provided outside the vehicle compartment, and an outdoor heat exchanger exiting the radiator An outdoor expansion valve for depressurizing the refrigerant flowing into the compressor, a first on-off valve provided between the discharge side of the compressor and the inlet side of the radiator, and a branch on the upstream side of the first on-off valve. A bypass pipe for bypassing the radiator and the outdoor expansion valve and allowing the refrigerant discharged from the compressor to flow to the outdoor heat exchanger, a second on-off valve provided in the bypass pipe, and an air flow passage from the vehicle Auxiliary heating device for heating the air supplied to the room and a control device By this control device, the first on-off valve is opened and the second on-off valve is closed, whereby the refrigerant discharged from the compressor is caused to flow through the radiator to dissipate the heat, and the radiated refrigerant is decompressed by the outdoor expansion valve. After that, the heating mode in which heat is absorbed by the outdoor heat exchanger, the outdoor expansion valve is fully closed, the first on-off valve is closed, and the second on-off valve is opened to bypass the refrigerant discharged from the compressor. In the vehicle air conditioner that performs switching by switching the dehumidifying heating mode for causing the auxiliary heating device to generate heat while depressurizing the refrigerant that has been radiated to the outdoor heat exchanger and depressurizing the radiated refrigerant, When the apparatus switches from the dehumidifying / heating mode to the heating mode, after reducing the pressure difference before and after the first on-off valve, the noise improvement control is executed to open the first on-off valve and close the second on-off valve. So When switching from the heating mode to the heating mode, it is possible when opening the first on-off valve, the refrigerant toward the radiator side is greatly suppressed or eliminated in that rapidly flows. Thereby, at the time of switching from the dehumidifying and heating mode to the heating mode, noise generated when the first on-off valve is opened can be eliminated or reduced.
In this case, in the noise improvement control, the controller opens the outdoor expansion valve and controls the rotation speed of the compressor, or stops the compressor to perform the first opening / closing operation. If the pressure difference before and after the valve is reduced and the pressure difference falls below a predetermined value, the first on-off valve is opened and the second on-off valve is closed. The pressure difference before and after the first on-off valve is increased by increasing the pressure on the refrigerant downstream side of the first on-off valve and lowering the pressure on the refrigerant upstream side of the first on-off valve by controlling the rotational speed of the compressor or stopping. Can be effectively reduced, the heating mode can be quickly switched, and noise generated at the time of switching can be effectively eliminated or reduced.
According to the seventh aspect of the present invention, in the noise improvement control, the control device reduces the pressure difference before and after the first on-off valve by controlling the outdoor expansion valve in the heating mode and stopping the compressor. The outdoor expansion valve may be used when the pressure difference is equal to or less than a predetermined value, or when the first on-off valve is opened and the second on-off valve is closed after a predetermined time has elapsed since the compressor was stopped. The pressure difference between the front and rear of the first on-off valve is quickly increased by increasing the pressure downstream of the first on-off valve by lowering the pressure and lowering the pressure on the upstream side of the refrigerant by stopping the compressor. It is possible to reduce the size and switch accurately to the heating mode, and to effectively eliminate or reduce the noise generated at the time of switching.
Further, in these, as in the invention of claim 8, the refrigerant is opened in the heating mode and the refrigerant discharged from the outdoor heat exchanger is sucked into the compressor, and the refrigerant discharged from the outdoor heat exchanger is closed in the dehumidifying heating mode. In the case of providing the third on-off valve in a state where it flows to the heat absorber, the control device opens and closes the third on-off valve after opening the first on-off valve and closing the second on-off valve in the noise improvement control. If the third on-off valve is opened when the pressure difference of the pressure becomes equal to or less than a predetermined value, when the third on-off valve is opened when switching from the dehumidifying heating mode to the heating mode, the compressor side It is possible to greatly suppress or eliminate the sudden flow of the refrigerant toward the. Thereby, at the time of switching from the dehumidifying / heating mode to the heating mode, noise generated when the third on-off valve is opened can be eliminated or reduced.
Further, according to the ninth aspect of the present invention, if the control device increases the heat generation of the auxiliary heating device and opens the third on-off valve in the noise improvement control, the heat generation of the auxiliary heating device is reduced. Further, it is possible to suppress a decrease in the blowing temperature that occurs when switching from the dehumidifying heating mode to the heating mode.
In this case, as in the invention of claim 10, if the control device reduces the heat generation of the auxiliary heating device when the high-pressure side pressure exceeds a predetermined value after opening the third on-off valve, After switching to the heating mode, the passenger compartment can be heated by the radiator and auxiliary heating device until the high-pressure side pressure rises. Comfortable vehicle interior heating can be realized.

It is a block diagram of the air conditioning apparatus for vehicles of one Embodiment to which this invention is applied (heating mode, dehumidification heating mode, dehumidification cooling mode, and cooling mode). It is a block diagram of the electric circuit of the controller of the vehicle air conditioner of FIG. It is a block diagram at the time of the MAX cooling mode (maximum cooling mode) of the vehicle air conditioner of FIG. It is a timing chart of each apparatus explaining an example of the noise improvement control which the controller of FIG. 2 performs when switching from heating mode to dehumidification heating mode. It is a timing chart of each apparatus explaining an example of the noise improvement control which the controller of FIG. 2 performs when switching from dehumidification heating mode to heating mode.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a configuration diagram of a vehicle air conditioner 1 according to an embodiment of the present invention. A vehicle according to an embodiment to which the present invention is applied is an electric vehicle (EV) in which an engine (internal combustion engine) is not mounted, and travels by driving an electric motor for traveling with electric power charged in a battery. Yes (both not shown), the vehicle air conditioner 1 of the present invention is also driven by the power of the battery. That is, the vehicle air conditioner 1 of the embodiment performs a heating mode by a heat pump operation using a refrigerant circuit in an electric vehicle that cannot be heated by engine waste heat, and further includes a dehumidifying heating mode, a dehumidifying cooling mode, a cooling mode, Each operation mode of the MAX cooling mode (maximum cooling mode) is selectively executed.
The present invention is effective not only for electric vehicles but also for so-called hybrid vehicles that use an engine and an electric motor for traveling, and is also applicable to ordinary vehicles that run on an engine. Needless to say.
The vehicle air conditioner 1 according to the embodiment performs air conditioning (heating, cooling, dehumidification, and ventilation) in a vehicle interior of an electric vehicle, and includes an electric compressor 2 that compresses refrigerant and vehicle interior air. Is provided in the air flow passage 3 of the HVAC unit 10 through which air is circulated, and the high-temperature and high-pressure refrigerant discharged from the compressor 2 flows in through the refrigerant pipe 13G, and dissipates the refrigerant into the vehicle compartment. And an outdoor expansion valve 6 comprising an electric valve that decompresses and expands the refrigerant during heating, and functions as a radiator during cooling and functions as a radiator during heating, and exchanges heat between the refrigerant and the outside air so as to function as an evaporator during heating. An outdoor heat exchanger 7 that performs the above operation, an indoor expansion valve 8 that is an electric valve that decompresses and expands the refrigerant, and a heat absorber 9 that is provided in the air flow passage 3 and absorbs heat from outside the vehicle interior to the refrigerant during cooling and dehumidification. And accumulator 12 etc. Are sequentially connected by a refrigerant pipe 13, the refrigerant circuit R is formed.
The refrigerant circuit R is filled with a predetermined amount of refrigerant and lubricating oil. The outdoor heat exchanger 7 is provided with an outdoor blower 15. The outdoor blower 15 exchanges heat between the outside air and the refrigerant by forcibly passing outside air through the outdoor heat exchanger 7, so that the outdoor air blower 15 can also be used outdoors even when the vehicle is stopped (that is, the vehicle speed is 0 km / h). It is comprised so that external air may be ventilated by the heat exchanger 7. FIG.
The outdoor heat exchanger 7 has a receiver dryer section 14 and a supercooling section 16 sequentially on the downstream side of the refrigerant, and the refrigerant pipe 13A exiting from the outdoor heat exchanger 7 is received via an electromagnetic valve 17 opened during cooling. The refrigerant pipe 13 B connected to the dryer unit 14 and on the outlet side of the supercooling unit 16 is connected to the inlet side of the heat absorber 9 via the indoor expansion valve 8. In addition, the receiver dryer part 14 and the supercooling part 16 structurally constitute a part of the outdoor heat exchanger 7.
The refrigerant pipe 13B between the subcooling section 16 and the indoor expansion valve 8 is provided in a heat exchange relationship with the refrigerant pipe 13C on the outlet side of the heat absorber 9, and constitutes an internal heat exchanger 19 together. Thus, the refrigerant flowing into the indoor expansion valve 8 through the refrigerant pipe 13B is cooled (supercooled) by the low-temperature refrigerant that has exited the heat absorber 9.
Further, the refrigerant pipe 13A exiting from the outdoor heat exchanger 7 is branched into a refrigerant pipe 13D, and this branched refrigerant pipe 13D is downstream of the internal heat exchanger 19 via an electromagnetic valve 21 opened during heating. The refrigerant pipe 13C is connected in communication. The refrigerant pipe 13 C is connected to the accumulator 12, and the accumulator 12 is connected to the refrigerant suction side of the compressor 2. Further, the refrigerant pipe 13E on the outlet side of the radiator 4 is connected to the inlet side of the outdoor heat exchanger 7 via the outdoor expansion valve 6.
A refrigerant pipe 13G between the discharge side of the compressor 2 and the inlet side of the radiator 4 is provided with a solenoid valve 30 (which constitutes a flow path switching device) that is closed during dehumidification heating and MAX cooling described later. Yes. In this case, the refrigerant pipe 13G is branched into a bypass pipe 35 on the upstream side of the electromagnetic valve 30, and the bypass pipe 35 is opened by the electromagnetic valve 40 (which also constitutes a flow path switching device) during dehumidifying heating and MAX cooling. ) Through the refrigerant pipe 13E on the downstream side of the outdoor expansion valve 6. These bypass pipe 35, electromagnetic valve 30 and electromagnetic valve 40 constitute a bypass device 45 in the present invention.
Since the bypass device 45 is configured by the bypass pipe 35, the electromagnetic valve 30, and the electromagnetic valve 40, the dehumidifying heating mode or the MAX for allowing the refrigerant discharged from the compressor 2 to directly flow into the outdoor heat exchanger 7 as will be described later. Switching between the cooling mode and the heating mode in which the refrigerant discharged from the compressor 2 flows into the radiator 4, the dehumidifying cooling mode, and the cooling mode can be performed smoothly.
The air flow passage 3 on the air upstream side of the heat absorber 9 is formed with each of an outside air inlet and an inside air inlet (represented by the inlet 25 in FIG. 1). 25 is provided with a suction switching damper 26 for switching the air introduced into the air flow passage 3 between the inside air (inside air circulation mode) which is air inside the passenger compartment and the outside air (outside air introduction mode) which is outside the passenger compartment. Yes. Furthermore, an indoor blower (blower fan) 27 for supplying the introduced inside air or outside air to the air flow passage 3 is provided on the air downstream side of the suction switching damper 26.
Moreover, in FIG. 1, 23 is an auxiliary heater as an auxiliary heating device provided in the vehicle air conditioner 1 of the embodiment. The auxiliary heater 23 of the embodiment is composed of a PTC heater which is an electric heater, and is provided in the air flow passage 3 on the air upstream side of the radiator 4 with respect to the air flow in the air flow passage 3. Yes. When the auxiliary heater 23 is energized and generates heat, the air in the air flow passage 3 flowing into the radiator 4 through the heat absorber 9 is heated. In other words, the auxiliary heater 23 serves as a so-called heater core, which heats or complements the passenger compartment.
In addition, air in the air flow passage 3 on the upstream side of the auxiliary heater 23 flows into the air flow passage 3 and assists air (inside air or outside air) in the air flow passage 3 after passing through the heat absorber 9. An air mix damper 28 is provided for adjusting the ratio of ventilation through the heater 23 and the radiator 4. Further, FOOT (foot), VENT (vent), and DEF (def) outlets (represented by the outlet 29 as a representative in FIG. 1) are formed in the air flow passage 3 on the air downstream side of the radiator 4. The air outlet 29 is provided with an air outlet switching damper 31 that performs switching control of air blowing from the air outlets.
Next, in FIG. 2, reference numeral 32 denotes a controller (ECU) as a control device composed of a microcomputer which is an example of a computer provided with a processor. The controller 32 detects the outside air temperature (Tam) of the vehicle. The outside air temperature sensor 33 for detecting the outside air humidity, the HVAC suction temperature sensor 36 for detecting the temperature of the air sucked into the air flow passage 3 from the suction port 25, and the air (inside air) in the passenger compartment. An inside air temperature sensor 37 that detects the temperature, an inside air humidity sensor 38 that detects the humidity of the air in the vehicle interior, an indoor CO ₂ concentration sensor 39 that detects the carbon dioxide concentration in the vehicle interior, and an air outlet from the air outlet 29 And a discharge pressure sensor 41 for detecting the discharge refrigerant pressure (discharge pressure Pd) of the compressor 2. , A discharge temperature sensor 43 that detects the discharge refrigerant temperature of the compressor 2, a suction pressure sensor 44 that detects the suction refrigerant pressure of the compressor 2, and a suction temperature sensor 55 that detects the suction refrigerant temperature of the compressor 2. And a radiator temperature sensor 46 that detects the temperature of the radiator 4 (the temperature of the air that has passed through the radiator 4 or the temperature of the radiator 4 itself: the radiator temperature TH), and the refrigerant pressure (the radiator of the radiator 4). 4 or a radiator pressure sensor 47 that detects the pressure of the refrigerant immediately after exiting the radiator 4: the radiator pressure PCI, and the temperature of the heat absorber 9 (the temperature of the air passing through the heat absorber 9 or the heat absorption). The temperature of the heat exchanger 9 itself: a heat absorber temperature sensor 48 that detects the heat absorber temperature Te) and the refrigerant pressure of the heat absorber 9 (the pressure of the refrigerant in the heat absorber 9 or immediately after leaving the heat absorber 9). A heat absorber pressure sensor 49 for detecting the amount of solar radiation into the passenger compartment For example, a photosensor-type solar radiation sensor 51, a vehicle speed sensor 52 for detecting the moving speed (vehicle speed) of the vehicle, an air conditioning (air conditioner) operation unit 53 for setting a set temperature and an operation mode, and outdoor heat An outdoor heat exchanger temperature sensor 54 for detecting the temperature of the exchanger 7 (the temperature of the refrigerant immediately after leaving the outdoor heat exchanger 7 or the temperature of the outdoor heat exchanger 7 itself: the outdoor heat exchanger temperature TXO); The pressure of the outdoor heat exchanger pressure sensor 56 that detects the refrigerant pressure of the outdoor heat exchanger 7 (the pressure of the refrigerant in the outdoor heat exchanger 7 or immediately after exiting the outdoor heat exchanger 7: outdoor heat exchanger pressure PXO). Each output is connected. Further, the input of the controller 32 further includes an auxiliary heater temperature sensor for detecting the temperature of the auxiliary heater 23 (the temperature of the air immediately after being heated by the auxiliary heater 23 or the temperature of the auxiliary heater 23 itself: the auxiliary heater temperature Tptc). 50 outputs are also connected.
On the other hand, the output of the controller 32 includes the compressor 2, the outdoor blower 15, the indoor blower (blower fan) 27, the suction switching damper 26, the air mix damper 28, the outlet switching damper 31, and the outdoor expansion. Solenoid valve 6, indoor expansion valve 8, auxiliary heater 23, solenoid valve 30 (for dehumidification), solenoid valve 17 (for cooling), solenoid valve 21 (for heating), solenoid valve 40 (also for dehumidification) Is connected. And the controller 32 controls these based on the output of each sensor, and the setting input in the air-conditioning operation part 53. FIG.
Next, the operation of the vehicle air conditioner 1 having the above-described configuration will be described. In the embodiment, the controller 32 switches between the operation modes of the heating mode, the dehumidifying heating mode, the dehumidifying cooling mode, the cooling mode, and the MAX cooling mode (maximum cooling mode). First, an outline of refrigerant flow and control in each operation mode will be described.
(1) Heating mode When the heating mode is selected by the controller 32 (auto mode) or by the manual operation (manual mode) to the air conditioning operation unit 53, the controller 32 opens the solenoid valve 21 (for heating) and opens the solenoid valve. Close 17 (for cooling). Further, the electromagnetic valve 30 (for dehumidification) is opened, and the electromagnetic valve 40 (for dehumidification) is closed.
Then, the compressor 2 and each of the

blowers

15 and 27 are operated, and the air mix damper 28 is blown out from the indoor blower 27 and passes through the heat absorber 9 as shown by a broken line in FIG. It is assumed that air is passed through the auxiliary heater 23 and the radiator 4. As a result, the high-temperature and high-pressure gas refrigerant discharged from the compressor 2 flows into the radiator 4 from the refrigerant pipe 13G via the electromagnetic valve 30. Since the air in the airflow passage 3 is passed through the radiator 4, the air in the airflow passage 3 is converted into the high-temperature refrigerant in the radiator 4 (when the auxiliary heater 23 operates, the auxiliary heater 23 and the radiator 4. On the other hand, the refrigerant in the radiator 4 is cooled by being deprived of heat by the air, and is condensed and liquefied.
The refrigerant liquefied in the radiator 4 exits the radiator 4 and then reaches the outdoor expansion valve 6 through the refrigerant pipe 13E. The refrigerant flowing into the outdoor expansion valve 6 is decompressed there and then flows into the outdoor heat exchanger 7. The refrigerant flowing into the outdoor heat exchanger 7 evaporates, and pumps up heat from the outside air that is ventilated by traveling or by the outdoor blower 15. That is, the refrigerant circuit R becomes a heat pump. Then, the low-temperature refrigerant exiting the outdoor heat exchanger 7 enters the accumulator 12 from the refrigerant pipe 13C through the refrigerant pipe 13A, the electromagnetic valve 21 and the refrigerant pipe 13D, and is separated into gas and liquid there. Repeated circulation inhaled. Since the air heated by the radiator 4 (when the auxiliary heater 23 is operated, the auxiliary heater 23 and the radiator 4) is blown out from the outlet 29, the vehicle interior is thereby heated.
The controller 32 calculates a target radiator pressure PCO (target value of the radiator pressure PCI) from a target radiator temperature TCO (target value of the radiator temperature TH) calculated from a target outlet temperature TAO described later, and this target heat dissipation. The number of revolutions of the compressor 2 is controlled based on the compressor pressure PCO and the refrigerant pressure of the radiator 4 detected by the radiator pressure sensor 47 (radiator pressure PCI; high pressure of the refrigerant circuit R). Further, the controller 32 determines the valve opening degree of the outdoor expansion valve 6 based on the temperature of the radiator 4 (the radiator temperature TH) detected by the radiator temperature sensor 46 and the radiator pressure PCI detected by the radiator pressure sensor 47. And the supercooling degree SC of the refrigerant at the outlet of the radiator 4 is controlled. The target radiator temperature TCO is basically set to TCO = TAO, but a predetermined restriction on control is provided.
Further, in this heating mode, when the heating capacity by the radiator 4 is insufficient with respect to the heating capacity required for the vehicle interior air conditioning, the controller 32 assists so that the shortage is supplemented by the heat generated by the auxiliary heater 23. The energization of the heater 23 is controlled. Thereby, comfortable vehicle interior heating is realized and frost formation of the outdoor heat exchanger 7 is also suppressed. At this time, since the auxiliary heater 23 is disposed on the air upstream side of the radiator 4, the air flowing through the air flow passage 3 is vented to the auxiliary heater 23 before the radiator 4.
Here, when the auxiliary heater 23 is disposed on the air downstream side of the radiator 4, when the auxiliary heater 23 is configured by a PCT heater as in the embodiment, the temperature of the air flowing into the auxiliary heater 23 is determined by the radiator. 4, the resistance value of the PTC heater increases, the current value also decreases, and the heat generation amount decreases. However, by arranging the auxiliary heater 23 on the air upstream side of the radiator 4, Thus, the capacity of the auxiliary heater 23 composed of the PTC heater can be sufficiently exhibited.
(2) Dehumidification heating mode Next, in the dehumidification heating mode, the controller 32 opens the electromagnetic valve 17 and closes the electromagnetic valve 21. Further, the electromagnetic valve 30 is closed, the electromagnetic valve 40 is opened, and the valve opening degree of the outdoor expansion valve 6 is fully closed. Then, the compressor 2 and each of the

blowers

15 and 27 are operated, and the air mix damper 28 is blown out from the indoor blower 27 and passes through the heat absorber 9 as shown by a broken line in FIG. It is assumed that air is passed through the auxiliary heater 23 and the radiator 4.
Accordingly, the high-temperature and high-pressure gas refrigerant discharged from the compressor 2 to the refrigerant pipe 13G flows into the bypass pipe 35 without going to the radiator 4, passes through the electromagnetic valve 40, and is connected to the refrigerant pipe on the downstream side of the outdoor expansion valve 6. 13E. At this time, since the outdoor expansion valve 6 is fully closed, the refrigerant flows into the outdoor heat exchanger 7. The refrigerant flowing into the outdoor heat exchanger 7 is cooled and condensed by running there or by the outside air ventilated by the outdoor blower 15. The refrigerant that has exited the outdoor heat exchanger 7 sequentially flows from the refrigerant pipe 13 A through the electromagnetic valve 17 into the receiver dryer unit 14 and the supercooling unit 16. Here, the refrigerant is supercooled.
The refrigerant that has exited the supercooling section 16 of the outdoor heat exchanger 7 enters the refrigerant pipe 13 B, reaches the indoor expansion valve 8 through the internal heat exchanger 19. After the refrigerant is depressurized by the indoor expansion valve 8, it flows into the heat absorber 9 and evaporates. The air blown out from the indoor blower 27 by the heat absorption action at this time is cooled, and moisture in the air condenses and adheres to the heat absorber 9, so that the air in the air flow passage 3 is cooled, and Dehumidified. The refrigerant evaporated in the heat absorber 9 reaches the accumulator 12 through the refrigerant pipe 13C through the internal heat exchanger 19, and repeats circulation that is sucked into the compressor 2 there through.
At this time, since the valve opening degree of the outdoor expansion valve 6 is fully closed, it is possible to suppress or prevent inconvenience that the refrigerant discharged from the compressor 2 flows backward from the outdoor expansion valve 6 into the radiator 4. It becomes. Thereby, the fall of a refrigerant | coolant circulation amount can be suppressed or eliminated and air-conditioning capability can be ensured now. Further, in this dehumidifying and heating mode, the controller 32 energizes the auxiliary heater 23 to generate heat. As a result, the air cooled and dehumidified by the heat absorber 9 is further heated in the process of passing through the auxiliary heater 23 and the temperature rises, so that the dehumidifying heating in the passenger compartment is performed.
The controller 32 controls the rotational speed of the compressor 2 on the basis of the temperature of the heat absorber 9 (heat absorber temperature Te) detected by the heat absorber temperature sensor 48 and the target heat absorber temperature TEO that is the target value, and the auxiliary heater temperature. By controlling the energization (heat generation) of the auxiliary heater 23 based on the auxiliary heater temperature Tptc detected by the sensor 50 and the target radiator temperature TCO described above, while appropriately cooling and dehumidifying the air in the heat absorber 9, A decrease in the temperature of the air blown from the outlet 29 into the passenger compartment by heating by the auxiliary heater 23 is accurately prevented.
As a result, it is possible to control the temperature to an appropriate heating temperature while dehumidifying the air blown into the vehicle interior, and it is possible to realize comfortable and efficient dehumidification heating in the vehicle interior. Further, as described above, in the dehumidifying heating mode, the air mix damper 28 is in a state where all the air in the air flow passage 3 is passed through the auxiliary heater 23 and the radiator 4, so that the air passing through the heat absorber 9 is efficiently assisted. Heating by the heater 23 can improve the energy saving performance, and the controllability of the dehumidifying heating air conditioning can also be improved.
In addition, since the auxiliary heater 23 is disposed on the air upstream side of the radiator 4, the air heated by the auxiliary heater 23 passes through the radiator 4. In this dehumidifying heating mode, the refrigerant is supplied to the radiator 4. Therefore, the disadvantage that the radiator 4 absorbs heat from the air heated by the auxiliary heater 23 is also eliminated. That is, the temperature of the air blown out into the vehicle compartment by the radiator 4 is suppressed, and the COP is improved.
(3) Dehumidifying and Cooling Mode Next, in the dehumidifying and cooling mode, the controller 32 opens the electromagnetic valve 17 and closes the electromagnetic valve 21. Further, the electromagnetic valve 30 is opened and the electromagnetic valve 40 is closed. Then, the compressor 2 and each of the

blowers

15 and 27 are operated, and the air mix damper 28 is blown out from the indoor blower 27 and passes through the heat absorber 9 as shown by a broken line in FIG. It is assumed that air is passed through the auxiliary heater 23 and the radiator 4. As a result, the high-temperature and high-pressure gas refrigerant discharged from the compressor 2 flows into the radiator 4 from the refrigerant pipe 13G via the electromagnetic valve 30. Since the air in the air flow passage 3 is passed through the radiator 4, the air in the air flow passage 3 is heated by the high-temperature refrigerant in the radiator 4, while the refrigerant in the radiator 4 heats the air. It is deprived and cooled, and condensates.
The refrigerant that has exited the radiator 4 reaches the outdoor expansion valve 6 through the refrigerant pipe 13E, and flows into the outdoor heat exchanger 7 through the outdoor expansion valve 6 that is controlled to open. The refrigerant flowing into the outdoor heat exchanger 7 is cooled and condensed by running there or by the outside air ventilated by the outdoor blower 15. The refrigerant that has exited the outdoor heat exchanger 7 sequentially flows from the refrigerant pipe 13 A through the electromagnetic valve 17 into the receiver dryer unit 14 and the supercooling unit 16. Here, the refrigerant is supercooled.
The refrigerant that has exited the supercooling section 16 of the outdoor heat exchanger 7 enters the refrigerant pipe 13 B, reaches the indoor expansion valve 8 through the internal heat exchanger 19. After the refrigerant is depressurized by the indoor expansion valve 8, it flows into the heat absorber 9 and evaporates. Since the moisture in the air blown out from the indoor blower 27 by the heat absorption action at this time condenses and adheres to the heat absorber 9, the air is cooled and dehumidified.
The refrigerant evaporated in the heat absorber 9 reaches the accumulator 12 through the refrigerant pipe 13C through the internal heat exchanger 19, and repeats circulation that is sucked into the compressor 2 there through. In this dehumidifying and cooling mode, the controller 32 does not energize the auxiliary heater 23, so the air cooled by the heat absorber 9 is reheated in the process of passing through the radiator 4 (the heat dissipation capability is lower than that during heating). The As a result, dehumidifying and cooling in the passenger compartment is performed.
The controller 32 controls the rotational speed of the compressor 2 based on the temperature of the heat absorber 9 (heat absorber temperature Te) detected by the heat absorber temperature sensor 48, and also uses the outdoor expansion valve based on the high pressure of the refrigerant circuit R described above. 6 is controlled to control the refrigerant pressure of the radiator 4 (radiator pressure PCI).
(4) Cooling Mode Next, in the cooling mode, the controller 32 fully opens the valve opening degree of the outdoor expansion valve 6 in the dehumidifying and cooling mode. The controller 32 controls the air mix damper 28, and the air in the air flow passage 3 after being blown out from the indoor blower 27 and passing through the heat absorber 9 as shown by a solid line in FIG. The rate of ventilation through the vessel 4 is adjusted. Further, the controller 32 does not energize the auxiliary heater 23.
As a result, the high-temperature and high-pressure gas refrigerant discharged from the compressor 2 flows into the radiator 4 from the refrigerant pipe 13G via the electromagnetic valve 30, and the refrigerant exiting the radiator 4 passes through the refrigerant pipe 13E and the outdoor expansion valve 6. To. At this time, since the outdoor expansion valve 6 is fully opened, the refrigerant passes through it and flows into the outdoor heat exchanger 7 as it is, where it is cooled by air or by outside air that is ventilated by the outdoor blower 15 and condensed. Liquefaction. The refrigerant that has exited the outdoor heat exchanger 7 sequentially flows from the refrigerant pipe 13 A through the electromagnetic valve 17 into the receiver dryer unit 14 and the supercooling unit 16. Here, the refrigerant is supercooled.
The refrigerant that has exited the supercooling section 16 of the outdoor heat exchanger 7 enters the refrigerant pipe 13 B, reaches the indoor expansion valve 8 through the internal heat exchanger 19. After the refrigerant is depressurized by the indoor expansion valve 8, it flows into the heat absorber 9 and evaporates. The air blown out from the indoor blower 27 by the heat absorption action at this time is cooled. Further, moisture in the air condenses and adheres to the heat absorber 9.
The refrigerant evaporated in the heat absorber 9 reaches the accumulator 12 through the refrigerant pipe 13C through the internal heat exchanger 19, and repeats circulation that is sucked into the compressor 2 there through. Since the air cooled and dehumidified by the heat absorber 9 is blown into the vehicle interior from the air outlet 29 (partly passes through the radiator 4 to exchange heat), the vehicle interior is thereby cooled. become. In this cooling mode, the controller 32 rotates the compressor 2 based on the temperature of the heat absorber 9 (heat absorber temperature Te) detected by the heat absorber temperature sensor 48 and the target heat absorber temperature TEO that is the target value. To control.
(5) MAX cooling mode (maximum cooling mode)
Next, in the MAX cooling mode as the maximum cooling mode, the controller 32 opens the electromagnetic valve 17 and closes the electromagnetic valve 21. Further, the electromagnetic valve 30 is closed, the electromagnetic valve 40 is opened, and the valve opening degree of the outdoor expansion valve 6 is fully closed. Then, the compressor 2 and the

blowers

15 and 27 are operated, and the air mix damper 28 keeps the air in the air flow passage 3 from passing through the auxiliary heater 23 and the radiator 4 as shown in FIG. However, there is no problem even if it is ventilated somewhat. Further, the controller 32 does not energize the auxiliary heater 23.
Accordingly, the high-temperature and high-pressure gas refrigerant discharged from the compressor 2 to the refrigerant pipe 13G flows into the bypass pipe 35 without going to the radiator 4, passes through the electromagnetic valve 40, and is connected to the refrigerant pipe on the downstream side of the outdoor expansion valve 6. 13E. At this time, since the outdoor expansion valve 6 is fully closed, the refrigerant flows into the outdoor heat exchanger 7. The refrigerant flowing into the outdoor heat exchanger 7 is cooled and condensed by running there or by the outside air ventilated by the outdoor blower 15. The refrigerant that has exited the outdoor heat exchanger 7 sequentially flows from the refrigerant pipe 13 A through the electromagnetic valve 17 into the receiver dryer unit 14 and the supercooling unit 16. Here, the refrigerant is supercooled.
The refrigerant that has exited the supercooling section 16 of the outdoor heat exchanger 7 enters the refrigerant pipe 13 B, reaches the indoor expansion valve 8 through the internal heat exchanger 19. After the refrigerant is depressurized by the indoor expansion valve 8, it flows into the heat absorber 9 and evaporates. The air blown out from the indoor blower 27 by the heat absorption action at this time is cooled. In addition, since moisture in the air condenses and adheres to the heat absorber 9, the air in the air flow passage 3 is dehumidified. The refrigerant evaporated in the heat absorber 9 reaches the accumulator 12 through the refrigerant pipe 13C through the internal heat exchanger 19, and repeats circulation that is sucked into the compressor 2 there through. At this time, since the outdoor expansion valve 6 is fully closed, similarly, it is possible to suppress or prevent the disadvantage that the refrigerant discharged from the compressor 2 flows backward from the outdoor expansion valve 6 into the radiator 4. . Thereby, the fall of a refrigerant | coolant circulation amount can be suppressed or eliminated and air-conditioning capability can be ensured now.
Here, since the high-temperature refrigerant flows through the radiator 4 in the cooling mode described above, direct heat conduction from the radiator 4 to the HVAC unit 10 occurs not a little, but in this MAX cooling mode, the refrigerant flows into the radiator 4. Therefore, the air in the air flow passage 3 from the heat absorber 9 is not heated by the heat transmitted from the radiator 4 to the HVAC unit 10. Therefore, powerful cooling of the passenger compartment is performed, and particularly in an environment where the outside air temperature Tam is high, the passenger compartment can be quickly cooled to realize comfortable air conditioning in the passenger compartment. Also in this MAX cooling mode, the controller 32 rotates the compressor 2 based on the temperature of the heat absorber 9 (heat absorber temperature Te) detected by the heat absorber temperature sensor 48 and the target heat absorber temperature TEO that is the target value. Control the number.
(6) Switching of operation mode The air flowing through the air flow passage 3 is cooled by the heat absorber 9 and heated by the heat radiator 4 (and the auxiliary heater 23) in each of the operation modes (adjusted by the air mix damper 28). ) And is blown out from the air outlet 29 into the passenger compartment. The controller 32 is set by the air-conditioning operation unit 53, the outside air temperature Tam detected by the outside air temperature sensor 33, the temperature in the vehicle interior detected by the inside air temperature sensor 37, the blower voltage, the amount of solar radiation detected by the solar radiation sensor 51, and the like. The target blowout temperature TAO is calculated based on the target passenger compartment temperature (set temperature) in the passenger compartment, and the temperature of the air blown from the blowout port 29 is controlled to this target blowout temperature TAO by switching each operation mode.
In this case, the controller 32 determines whether the outside air temperature Tam, the humidity in the vehicle interior, the target outlet temperature TAO, the radiator temperature TH, the target radiator temperature TCO, the heat absorber temperature Te, the target heat absorber temperature TEO, or the dehumidification request in the vehicle interior. By switching each operation mode based on parameters such as, etc., it switches between heating mode, dehumidifying heating mode, dehumidifying cooling mode, cooling mode and MAX cooling mode accurately according to the environmental conditions and necessity of dehumidification. In addition, efficient cabin air conditioning is realized.
(7) Noise improvement control when switching from heating mode to dehumidifying heating mode Next, referring to FIG. 4, when switching the operation mode of the vehicle air conditioner 1 from the heating mode described above to the dehumidifying heating mode. An example of the noise improvement control executed by the controller 32 will be described. The timing chart of FIG. 4 shows the pressure difference ΔPdx before and after the electromagnetic valve 40 (second on-off valve of the present invention) when switching from the heating mode to the dehumidifying heating mode, and the blowing temperature detected by the blowing temperature sensor 41 (described above). The temperature of the air blown into the vehicle compartment from the outlet 29), the auxiliary heater temperature Tptc detected by the auxiliary heater temperature sensor 50, the rotational speed NC of the compressor 2, the valve opening degree of the outdoor expansion valve 6, and The output (energization amount or heat generation amount) of the auxiliary heater 23, the solenoid valve 40, the solenoid valve 30 (first on-off valve of the present invention), the solenoid valve 17, and the solenoid valve 21 (third on-off valve of the present invention). Shows the state.
The pressure difference ΔPdx before and after the electromagnetic valve 40 (second on-off valve) is determined by the pressure Pd on the upstream side (front) of the refrigerant of the electromagnetic valve 40 detected by the discharge pressure sensor 42 and the outdoor heat exchanger temperature sensor 54. The outdoor heat exchanger pressure PXO on the downstream side (rear side) of the solenoid valve 40 converted from the temperature of the refrigerant immediately after coming out of the outdoor heat exchanger 7 to be detected (outdoor heat exchanger temperature TXO) (outdoor as in the embodiment) When the heat exchanger pressure sensor 56 is provided, the difference (ΔPdx = Pd−PXO) with respect to the outdoor heat exchanger pressure PCO detected by the outdoor heat exchanger pressure sensor 56 may be used. The controller 32 calculates.
The controller 32 also calculates a pressure difference ΔPix before and after the electromagnetic valve 30 (first on-off valve) in noise improvement control described later. In this case, the controller 32 uses the pressure Pd on the refrigerant upstream side (front) of the electromagnetic valve 30 detected by the discharge pressure sensor 42 and the pressure on the refrigerant downstream side (rear) of the electromagnetic valve 30 detected by the radiator pressure sensor 47. Based on a certain radiator pressure PCI, the difference ΔPix (ΔPix = Pd−PCI) is defined as a pressure difference before and after the solenoid valve 30.
Furthermore, the controller 32 also calculates a pressure difference ΔPxs before and after the solenoid valve 21 (third on-off valve) in noise improvement control described later. In this case, the controller 32 is on the refrigerant upstream side of the solenoid valve 21 (outdoor heat exchanger temperature TXO) converted from the refrigerant temperature (outdoor heat exchanger temperature TXO) immediately after coming out of the outdoor heat exchanger 7 detected by the outdoor heat exchanger temperature sensor 54. Previous heat exchanger pressure PXO (when the outdoor heat exchanger pressure sensor 56 is provided as in the embodiment, the outdoor heat exchanger pressure PCO detected by the outdoor heat exchanger pressure sensor 56 may be used. The difference (ΔPxs = PXO−Ps) between the suction pressure Ps on the refrigerant downstream side (rear) of the solenoid valve 21 calculated from the suction temperature of the compressor 2 detected by the suction temperature sensor 55 and the solenoid valve 21 The pressure difference between the front and rear is the same (the same applies to the noise improvement control below).
(7-1) Noise improvement control when switching from heating mode to dehumidifying heating mode (Part 1)
When the operation mode is switched from the heating mode to the dehumidifying heating mode, in the heating mode, the pressure difference ΔPdx before and after the electromagnetic valve 40 has a large value as shown in FIG. Therefore, when the electromagnetic valve 40 that is closed in the heating mode is opened to enter the dehumidifying heating mode with such a pressure difference, the direction from the discharge side of the compressor 2 through the electromagnetic valve 40 to the inlet side of the outdoor heat exchanger 7 Then, the refrigerant suddenly flows through the bypass pipe 35, and a large noise (noise) is generated in the solenoid valve 40.
Therefore, the controller 32 executes noise improvement control described below when switching the operation mode from the heating mode to the dehumidifying heating mode. When switching from the heating mode to the dehumidifying heating mode, the controller 32 first causes the auxiliary heater 23 to generate heat and increase its output (energization amount or heat generation amount). In this case, the controller 32 increases the output to the predetermined value D (FIG. 4) that is higher than the target value C (FIG. 4) of the output of the auxiliary heater 23 in the dehumidifying heating mode. Thereby, the auxiliary heater temperature Tptc rises.
When the auxiliary heater temperature Tptc becomes equal to or higher than the predetermined value B in FIG. 4, the controller 32 opens the electromagnetic valve 17 and closes the electromagnetic valve 21. As a result, the refrigerant circuit R is switched to a state in which the refrigerant discharged from the outdoor heat exchanger 7 flows to the heat absorber 9 via the receiver dryer section 14, the supercooling section 16, the internal heat exchanger 19, and the indoor expansion valve 8. The controller 32 then controls the output of the auxiliary heater 23 to be the target value C in the dehumidifying and heating mode described above.
In addition, when the auxiliary heater temperature Tptc is equal to or higher than the predetermined value B, the controller 32 sets the pressure difference Pdx before and after the electromagnetic valve 40 to the predetermined value A (for example, before switching the electromagnetic valve 40 and the electromagnetic valve 30). The opening degree of the outdoor expansion valve 6 is increased and the rotational speed NC of the compressor 2 is adjusted (controlled in a decreasing direction) so as to be equal to or lower than 0.2 MPa. By increasing the valve opening degree of the outdoor expansion valve 6, the outdoor heat exchanger pressure PXO increases, and by controlling the rotational speed NC of the compressor 2 to decrease, the discharge pressure Pd decreases. The pressure difference Pdx before and after the valve 40 (= Pd−PXO) becomes smaller.
When the pressure difference ΔPdx is reduced below the predetermined value A in FIG. 4, the controller 32 opens the electromagnetic valve 40, closes the electromagnetic valve 30, fully closes the outdoor expansion valve 6, and controls the compressor 2. Is controlled during dehumidifying heating to shift to the air conditioning operation in the dehumidifying heating mode.
(7-2) Noise improvement control when switching from heating mode to dehumidifying heating mode (part 2)
Here, in the noise improvement control of the above embodiment, the controller 32 increases the valve opening degree of the outdoor expansion valve 6 so that the pressure difference ΔPdx before and after the electromagnetic valve 40 is equal to or less than the predetermined value A, and the compressor 2 However, the present invention is not limited to this, and the valve opening degree of the outdoor expansion valve 6 is fully opened (FIG. 4), and the rotation speed NC of the compressor 2 is a predetermined low speed that is a predetermined low value. NC1 (FIG. 4. For example, 800 rpm) may be used. Since the outdoor expansion valve 6 is fully opened and the rotational speed NC of the compressor 2 is controlled to a low predetermined rotational speed NC1, the outdoor heat exchanger pressure PXO increases and the discharge pressure Pd decreases. The pressure difference Pdx before and after becomes smaller. Also in this case, when the pressure difference ΔPdx is reduced to the predetermined value A or less, the controller 32 opens the electromagnetic valve 40, closes the electromagnetic valve 30, and fully closes the outdoor expansion valve 6, thereby dehumidifying. Transition to air conditioning operation in heating mode.
(7-3) Noise improvement control at the time of switching from the heating mode to the dehumidifying heating mode (part 3)
Further, in the noise improvement control, the controller 32 fully opens the outdoor expansion valve 6 and sets the rotational speed NC of the compressor 2 to the predetermined rotational speed NC1, for a predetermined time (for example, 10 seconds, etc. FIG. 4). After the elapse of time, the electromagnetic valve 40 may be opened, the electromagnetic valve 30 may be closed, and the outdoor expansion valve 6 may be fully closed to start the air conditioning operation in the dehumidifying heating mode.
Thus, when switching the operation mode from the heating mode to the dehumidifying heating mode, the controller 32 reduces the pressure difference ΔPdx before and after the electromagnetic valve 40 (second on-off valve), then opens the electromagnetic valve 40, and opens the electromagnetic valve 30. Since the noise improvement control for closing the (first on-off valve) and fully closing the outdoor expansion valve 6 is performed, when switching from the heating mode to the dehumidifying heating mode, when the electromagnetic valve 40 is opened, bypass is performed. It is possible to greatly suppress or eliminate the sudden flow of the refrigerant through the pipe 35 toward the outdoor heat exchanger 7 side. Thereby, at the time of switching from the heating mode to the dehumidifying heating mode, noise generated when the electromagnetic valve 40 is opened can be eliminated or reduced.
In particular, in the noise improvement control (noise improvement control at the time of switching from the heating mode to the dehumidifying heating mode (1)), the controller 32 increases the valve opening of the outdoor expansion valve 6 and rotates the compressor 2. By controlling the number NC, the pressure difference ΔPdx before and after the electromagnetic valve 40 is reduced, and when the pressure difference ΔPdx becomes a predetermined value A or less, the electromagnetic valve 40 is opened, the electromagnetic valve 30 is closed, and the outdoor expansion is performed. Since the valve 6 is fully closed, the pressure on the refrigerant downstream side of the electromagnetic valve 40 is increased by increasing the valve opening of the outdoor expansion valve 6, and the refrigerant upstream of the electromagnetic valve 40 is controlled by controlling the rotational speed NC of the compressor 2. By reducing the pressure on the side, the pressure difference ΔPdx before and after the electromagnetic valve 40 can be effectively reduced, the mode can be quickly switched to the dehumidifying heating mode, and the noise generated at the time of switching can be effectively eliminated or reduced. I can .
In the noise improvement control (noise improvement control at the time of switching from the heating mode to the dehumidifying heating mode (No. 2), (No. 3)), the controller 32 fully opens the outdoor expansion valve 6 and the compressor 2 The pressure difference ΔPdx before and after the electromagnetic valve 40 is reduced by setting the rotational speed NC to a predetermined low value, and when the pressure difference ΔPdx becomes a predetermined value A or less, or the rotational speed NC of the compressor 2 Since the solenoid valve 40 is opened, the solenoid valve 30 is closed, and the outdoor expansion valve 6 is fully closed after a lapse of a predetermined time since the low value is reduced, the outdoor expansion valve 6 is fully opened. The pressure difference ΔPdx before and after the solenoid valve 40 is quickly reduced by raising the pressure and lowering the pressure upstream of the refrigerant of the solenoid valve 40 by reducing the rotational speed NC of the compressor 2 and switching to the dehumidifying heating mode accurately. And cut Effectively eliminate noise generated during recombination, or made so that it is possible to reduce.
Here, in the noise improvement control, since the rotational speed NC of the compressor 2 is lowered, there is a risk that the temperature of the air blown into the passenger compartment (blowing temperature) is lowered and the comfort is deteriorated. However, as described above, in the embodiment, when the controller 32 switches from the heating mode to the dehumidifying heating mode, first, the auxiliary heater 23 generates heat, and when the temperature Tptc of the auxiliary heater 23 becomes a predetermined value B or more, the outdoor heat Since the solenoid valve 17 and the solenoid valve 21 are switched to a state where the refrigerant discharged from the exchanger 7 flows to the heat absorber 9, the control of the outdoor expansion valve 6 and the compressor 2 in the noise improvement control is started. As shown in Fig. 5, the blowout temperature is kept substantially constant even in the process of switching from the heating mode to the dehumidifying heating mode. Thereby, the fall of the blowing temperature produced at the time of switching from heating mode to dehumidification heating mode is suppressed, and it becomes possible to implement | achieve comfortable vehicle interior air conditioning.
(8) Noise improvement control at the time of switching from the dehumidifying and heating mode to the heating mode Next, referring to FIG. 5, when switching the operation mode of the vehicle air conditioner 1 from the dehumidifying and heating mode to the heating mode described above. An example of the noise improvement control executed by the controller 32 will be described. The timing chart of FIG. 5 shows the pressure difference ΔPxs before and after the electromagnetic valve 21 (the third on-off valve of the present invention) when switching from the dehumidifying heating mode to the heating mode, and the electromagnetic valve 30 (the first on-off opening of the present invention). Pressure difference ΔPix before and after the valve), the blow-out temperature, the auxiliary heater temperature Tptc, the rotational speed NC of the compressor 2, the valve opening degree of the outdoor expansion valve 6, the output of the auxiliary heater 23, and the electromagnetic valve The state of 40 (second on-off valve of the present invention), solenoid valve 30, solenoid valve 17, and solenoid valve 21 is shown. It is assumed that the controller 32 calculates the pressure difference ΔPxs before and after the solenoid valve 21 and the pressure difference ΔPix before and after the solenoid valve 30 as described above.
(8-1) Noise improvement control at the time of switching from the dehumidifying heating mode to the heating mode (part 1)
When the operation mode is switched from the dehumidifying and heating mode to the heating mode, the pressure difference ΔPix before and after the electromagnetic valve 30 is a large value as shown in FIG. 5 in the dehumidifying and heating mode. Therefore, when the electromagnetic valve 30 that is closed in the dehumidifying heating mode is opened to enter the heating mode with such a pressure difference, the refrigerant flows from the discharge side of the compressor 2 through the electromagnetic valve 30 to the inlet side of the radiator 4. The refrigerant suddenly flows in the pipe 13G, and a large noise (noise) is generated in the solenoid valve 30.
In the dehumidifying and heating mode, the pressure difference ΔPxs before and after the solenoid valve 21 is also a large value as shown in FIG. Therefore, when the electromagnetic valve 21 that is closed in the dehumidifying heating mode is opened to enter the heating mode with such a pressure difference, the refrigerant suddenly flows from the outdoor heat exchanger 7 through the electromagnetic valve 21 toward the inlet side of the accumulator 12. Similarly, a large sound (noise) is generated in the solenoid valve 21.
Therefore, the controller 32 executes the noise improvement control described below also when switching the operation mode from the dehumidifying heating mode to the heating mode. Even when the controller 32 switches from the dehumidifying heating mode to the heating mode, first, the output (energization amount or heat generation amount) of the auxiliary heater 23 is increased. In this case, the controller 32 increases the output of the auxiliary heater 23 to a predetermined value D (FIG. 5) that is higher by a predetermined value than the target value C (FIG. 5) of the output of the auxiliary heater 23 executed in the dehumidifying heating mode. Let Thereby, auxiliary heater temperature Tptc rises.
In addition, before switching the solenoid valve 40 and the solenoid valve 30, the controller 32 expands the outdoor so that the pressure difference Pix before and after the solenoid valve 30 is equal to or less than a predetermined value A (for example, 0.2 MPa). The valve 6 is shifted from the closed state to the opened state, and the rotational speed NC of the compressor 2 is adjusted (controlled in a decreasing direction). By opening the outdoor expansion valve 6, the radiator pressure PCI increases, and the discharge pressure Pd decreases by controlling the rotational speed NC of the compressor 2 so that the pressure difference before and after the solenoid valve 30 is reduced. Pix (= Pd-PCI) becomes smaller.
When the pressure difference ΔPix is reduced below the predetermined value A in FIG. 5, the controller 32 opens the electromagnetic valve 30 and closes the electromagnetic valve 40. Since the solenoid valve 30 is opened and the solenoid valve 40 is closed, the refrigerant is depressurized by the outdoor expansion valve 6 via the radiator 4, and therefore the outdoor heat exchanger pressure PXO is reduced. The pressure difference ΔPxs (= PXO−Ps) before and after the valve 21 also decreases. Then, when the pressure difference ΔPxs before and after the electromagnetic valve 21 is reduced to a predetermined value E or less in FIG. 5, the controller 32 opens the electromagnetic valve 21 and closes the electromagnetic valve 17. As a result, the refrigerant circuit R switches to a state in which the refrigerant discharged from the outdoor heat exchanger 7 flows to the accumulator 12. In addition, the output (heat generation) of the auxiliary heater 23 is also reduced (output stop in this embodiment), and the operation is shifted to the air conditioning operation in the heating mode.
(8-2) Noise improvement control when switching from dehumidifying heating mode to heating mode (Part 2)
Here, in the noise improvement control of the above embodiment, the controller 32 opens the outdoor expansion valve 6 so that the pressure difference ΔPix before and after the electromagnetic valve 30 is equal to or less than the predetermined value A, and the rotational speed NC of the compressor 2 is set. Although the control is performed, when the pressure difference ΔPix does not become the predetermined value A or less, the compressor 2 may be further stopped (that is, the outdoor expansion valve 6 is opened and the compressor 2 is stopped). (FIG. 5). By opening the outdoor expansion valve 6 and stopping the compressor 2, the radiator pressure PCI and the discharge pressure Pd are in an equilibrium state, so the pressure difference Pix before and after the electromagnetic valve 30 becomes smaller. When the pressure difference ΔPix is reduced to a predetermined value A or less, the controller 32 opens the electromagnetic valve 30 and closes the electromagnetic valve 40. Then, the pressure difference ΔPxs before and after the electromagnetic valve 21 becomes equal to or less than a predetermined value E, the electromagnetic valve 17 is closed, the electromagnetic valve 21 is opened, the compressor 2 is started, and the output of the auxiliary heater 23 is also reduced (in the embodiment) The output is stopped), and the air-conditioning operation in the heating mode is started.
(8-3) Noise improvement control at the time of switching from the dehumidifying heating mode to the heating mode (part 3)
In addition, the outdoor expansion valve 6 may be shifted to the control state in the heating mode by the controller 32 from the start of the noise improvement control in this case (FIG. 5), and the compressor 2 may be stopped ( FIG. 5). Since the outdoor expansion valve 6 is opened and the control state during heating is set, and the compressor 2 is stopped, the radiator pressure PCI and the discharge pressure Pd are in an equilibrium state, so the pressure difference Pix before and after the electromagnetic valve 30 is It gets smaller.
When the pressure difference ΔPix is reduced to a predetermined value A or less, the controller 32 opens the electromagnetic valve 30 and closes the electromagnetic valve 40. Then, the pressure difference ΔPxs before and after the electromagnetic valve 21 becomes equal to or less than a predetermined value E, the electromagnetic valve 17 is closed, the electromagnetic valve 21 is opened, the compressor 2 is started, and the output of the auxiliary heater 23 is also reduced (in the embodiment) The output is stopped), and the air-conditioning operation in the heating mode is started.
(8-4) Noise improvement control at the time of switching from the dehumidifying heating mode to the heating mode (No. 4)
In the noise improvement control, the controller 32 sets the outdoor expansion valve 6 to the control state during heating, and after a predetermined time (for example, 10 seconds, FIG. 5) has elapsed since the compressor 2 was stopped. The electromagnetic valve 30 may be opened and the electromagnetic valve 40 may be closed. Also in this case, the pressure difference ΔPxs before and after the solenoid valve 21 becomes equal to or less than the predetermined value E, the solenoid valve 17 is closed, the solenoid valve 21 is opened, the compressor 2 is started, and the output of the auxiliary heater 23 is also reduced (implementation). In the example, the output is stopped), and the air-conditioning operation in the heating mode is started.
Thus, when switching from the dehumidifying and heating mode to the heating mode, the controller 32 reduces the pressure difference ΔPix before and after the electromagnetic valve 30 and then performs noise improvement control that opens the electromagnetic valve 30 and closes the electromagnetic valve 40. Therefore, when switching from the dehumidifying heating mode to the heating mode, when the electromagnetic valve 30 is opened, it is possible to greatly suppress or eliminate the sudden flow of refrigerant toward the radiator 4 side. Thereby, at the time of switching from the dehumidifying heating mode to the heating mode, noise generated when the electromagnetic valve 30 is opened can be eliminated or reduced.
In particular, in the noise improvement control (noise improvement control at the time of switching from the dehumidifying heating mode to the heating mode (part 1), (part 2)), the controller 32 opens the outdoor expansion valve 6 in the noise improvement control, and When the rotational speed NC of the compressor 2 is controlled or the pressure difference ΔPix before and after the electromagnetic valve 30 is reduced by stopping the compressor 2, and the pressure difference ΔPix becomes a predetermined value A or less, Since the electromagnetic valve 30 is opened and the electromagnetic valve 40 is closed, the pressure on the downstream side of the refrigerant of the electromagnetic valve 30 is increased by opening the outdoor expansion valve 6, and the rotational speed of the compressor 2 is controlled or stopped. By reducing the pressure on the upstream side of the refrigerant, the pressure difference before and after the solenoid valve 30 is effectively reduced, the heating mode is quickly switched, and the noise generated at the time of switching is effectively eliminated or reduced. Be able to.
Further, in the noise improvement control (noise improvement control at the time of switching from the dehumidifying heating mode to the heating mode (No. 3), (No. 4)), the controller 32 controls the outdoor expansion valve 6 in the heating mode in the noise improvement control. The pressure difference ΔPix before and after the solenoid valve 30 is reduced by stopping the compressor 2 and the compressor 2 is stopped when the pressure difference ΔPix becomes a predetermined value A or less. Since the solenoid valve 30 is opened and the solenoid valve 40 is closed after a lapse of a predetermined time from the beginning, the pressure on the refrigerant downstream side of the solenoid valve 30 is increased by opening the outdoor expansion valve 6, and the refrigerant upstream side of the solenoid valve 30 is stopped by stopping the compressor 2. The pressure difference ΔPix before and after the solenoid valve 30 is rapidly reduced by reducing the pressure of the solenoid valve 30 to accurately switch to the heating mode, and noise generated at the time of switching can be effectively eliminated or reduced. So as you can.
Furthermore, in addition to the noise improvement control in this case, the controller 32 opens the electromagnetic valve 30 and closes the electromagnetic valve 40, and when the pressure difference ΔPxs before and after the electromagnetic valve 21 becomes a predetermined value E or less, Since the solenoid valve 21 is opened and the solenoid valve 17 is opened, when switching from the dehumidifying and heating mode to the heating mode, the refrigerant may suddenly flow toward the compressor 2 when the solenoid valve 21 is opened. It can be greatly suppressed or eliminated. Thereby, at the time of switching from the dehumidifying heating mode to the heating mode, noise generated when the electromagnetic valve 21 is opened can be eliminated or reduced.
Here, even with such noise improvement control, the rotational speed NC of the compressor 2 is reduced or stopped, so that there is a risk that the temperature of the air blown into the passenger compartment (blowing temperature) is lowered and the comfort is deteriorated. is there. However, in the embodiment, when switching from the dehumidifying and heating mode to the heating mode, the controller 32 first increases the heat generation of the auxiliary heater 23 and opens (opens) the electromagnetic valve 21 and then decreases (stops) the heat generation. As shown in FIG. 5, the blowing temperature is maintained substantially constant even in the process of switching from the dehumidifying and heating mode to the heating mode. Thereby, the fall of the blowing temperature produced at the time of switching from dehumidification heating mode to heating mode is suppressed, and it becomes possible to implement | achieve comfortable vehicle interior air conditioning.
(8-5) Noise improvement control when switching from dehumidifying heating mode to heating mode (5)
Here, in the noise improvement control at the time of switching from the dehumidifying and heating mode to the heating mode, the controller 32 reduces the heat generation of the auxiliary heater 23 (stops in the embodiment) after opening the electromagnetic valve 21. Not limited to this, the auxiliary heater 23 is caused to generate heat even after shifting to the heating mode, for example, the stage where the radiator pressure PCI (high pressure side pressure, which may be the radiator temperature TH) has risen to a predetermined value (may be a target value) or more. Thus, the heat generation may be reduced (including stoppage). As a result, after switching to the heating mode, the vehicle interior can be heated by the radiator 4 and the auxiliary heater 23 until the high-pressure side pressure of the refrigerant circuit R rises. It is possible to more reliably eliminate the decrease and to realize comfortable vehicle interior heating.
In the noise improvement control at the time of switching from the dehumidifying heating mode to the heating mode as described above, the air flow rate of the indoor blower 27 is reduced, and after shifting to the heating mode, the radiator pressure PCI (or the radiator temperature TH is the target value). It may be made to return to the original air volume after it has risen to 1. As the air volume of the indoor blower 27 decreases, it is possible to further suppress the decrease in the blowing temperature.
Further, in the embodiment, the present invention is applied to the vehicle air conditioner 1 that switches between the operation modes of the heating mode, the dehumidifying heating mode, the dehumidifying cooling mode, the cooling mode, and the MAX cooling mode, but is not limited thereto. The present invention is also effective for a vehicle air conditioner that switches between a heating mode and a dehumidifying heating mode.
Furthermore, the switching control of each operation mode shown in the embodiment is not limited thereto, and the outside air temperature Tam, the humidity in the passenger compartment, the target outlet temperature TAO, depending on the capability and usage environment of the vehicle air conditioner, Adopt any one of parameters such as radiator temperature TH, target radiator temperature TCO, heat absorber temperature Te, target heat absorber temperature TEO, presence / absence of dehumidification request in vehicle interior, or a combination thereof, or all of them. Appropriate conditions should be set.
Furthermore, the auxiliary heating device is not limited to the auxiliary heater 23 shown in the embodiment, and a heat medium circulation circuit for heating the air in the air flow passage by circulating the heat medium heated by the heater, an engine You may utilize the heater core etc. which circulate the radiator water heated by. Further, the configuration of the refrigerant circuit R described in each of the above embodiments is not limited thereto, and it is needless to say that the refrigerant circuit R can be changed without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 Vehicle air conditioner 2 Compressor 3 Air flow path 4 Radiator 6 Outdoor expansion valve 7 Outdoor heat exchanger 8 Indoor expansion valve 9 Heat absorber 21 Solenoid valve (3rd on-off valve)
23 Auxiliary heater (auxiliary heating device)
27 Indoor blower
28 Air mix damper 30 Solenoid valve (first on-off valve)
40 Solenoid valve (second on-off valve)
31 Outlet switching damper 32 Controller (control device)
35 Bypass piping 45 Bypass device R Refrigerant circuit

Claims

A compressor for compressing the refrigerant;
An air flow passage through which air to be supplied into the passenger compartment flows;
A radiator for radiating the refrigerant to heat the air supplied from the air flow passage to the vehicle interior;
A heat absorber for absorbing the refrigerant and cooling the air supplied from the air flow passage to the vehicle interior;
An outdoor heat exchanger provided outside the vehicle compartment;
An outdoor expansion valve for decompressing the refrigerant flowing out of the radiator and flowing into the outdoor heat exchanger;
A first on-off valve provided between the discharge side of the compressor and the inlet side of the radiator;
A bypass pipe for branching upstream of the first on-off valve, bypassing the radiator and the outdoor expansion valve, and allowing the refrigerant discharged from the compressor to flow to the outdoor heat exchanger;
A second on-off valve provided in the bypass pipe;
An auxiliary heating device for heating the air supplied from the air flow passage to the vehicle interior;
Equipped with a control device,
The control device opens the first on-off valve and closes the second on-off valve, thereby allowing the refrigerant discharged from the compressor to flow through the radiator to dissipate the heat and dissipate the refrigerant that has been radiated. A heating mode for absorbing heat in the outdoor heat exchanger after depressurizing with an expansion valve;
The outdoor expansion valve is fully closed, the first on-off valve is closed, and the second on-off valve is opened, so that the refrigerant discharged from the compressor flows to the outdoor heat exchanger through the bypass pipe. In the vehicle air conditioner that performs heat dissipation by switching the dehumidifying heating mode for causing the auxiliary heating device to generate heat after depressurizing the refrigerant that has dissipated and absorbing heat with the heat absorber,
When the control device switches from the heating mode to the dehumidifying heating mode, after reducing the pressure difference before and after the second on-off valve, the control device opens the second on-off valve, and closes the first on-off valve, A vehicle air conditioner that performs noise improvement control for fully closing the outdoor expansion valve.
In the noise improvement control, the control device expands the valve opening of the outdoor expansion valve, and reduces the pressure difference before and after the second on-off valve by controlling the rotation speed of the compressor. The said 2nd on-off valve is opened when the said pressure difference becomes below a predetermined value, the said 1st on-off valve is closed, The said outdoor expansion valve is made into a full closure, The 1st aspect is characterized by the above-mentioned. Air conditioner for vehicles.
In the noise improvement control, the control device reduces the pressure difference before and after the second on-off valve by fully opening the outdoor expansion valve and setting the rotation speed of the compressor to a predetermined low value. , When the pressure difference is equal to or less than a predetermined value, or after a predetermined time has elapsed since the rotation speed of the compressor is set to the low value, the second on-off valve is opened, and the first on-off valve is closed, The vehicle air conditioner according to claim 1, wherein the outdoor expansion valve is fully closed.
The control device causes the auxiliary heating device to generate heat when switching from the heating mode to the dehumidifying heating mode, and when the temperature of the auxiliary heating device becomes a predetermined value or more, the refrigerant discharged from the outdoor heat exchanger 4. The vehicle air conditioner according to claim 2, wherein control of the outdoor expansion valve and the compressor in the noise improvement control is started while switching to a state in which the heat is passed through the heat absorber. 5.
A compressor for compressing the refrigerant;
An air flow passage through which air to be supplied into the passenger compartment flows;
A radiator for radiating the refrigerant to heat the air supplied from the air flow passage to the vehicle interior;
A heat absorber for absorbing the refrigerant and cooling the air supplied from the air flow passage to the vehicle interior;
An outdoor heat exchanger provided outside the vehicle compartment;
An outdoor expansion valve for decompressing the refrigerant flowing out of the radiator and flowing into the outdoor heat exchanger;
A first on-off valve provided between the discharge side of the compressor and the inlet side of the radiator;
A bypass pipe for branching upstream of the first on-off valve, bypassing the radiator and the outdoor expansion valve, and allowing the refrigerant discharged from the compressor to flow to the outdoor heat exchanger;
A second on-off valve provided in the bypass pipe;
An auxiliary heating device for heating the air supplied from the air flow passage to the vehicle interior;
Equipped with a control device,
The control device opens the first on-off valve and closes the second on-off valve, thereby allowing the refrigerant discharged from the compressor to flow through the radiator to dissipate the heat and dissipate the refrigerant that has been radiated. A heating mode for absorbing heat in the outdoor heat exchanger after depressurizing with an expansion valve;
The outdoor expansion valve is fully closed, the first on-off valve is closed, and the second on-off valve is opened, so that the refrigerant discharged from the compressor flows to the outdoor heat exchanger through the bypass pipe. In the vehicle air conditioner that performs heat dissipation by switching the dehumidifying heating mode for causing the auxiliary heating device to generate heat after depressurizing the refrigerant that has dissipated and absorbing heat with the heat absorber,
The control device, when switching from the dehumidifying heating mode to the heating mode, reduces the pressure difference before and after the first on-off valve, then opens the first on-off valve, and closes the second on-off valve. An air conditioner for a vehicle that performs improvement control.
In the noise improvement control, the control device opens the outdoor expansion valve and controls the rotation speed of the compressor, or stops the compressor so that the pressure difference between before and after the first on-off valve. The vehicle air conditioner according to claim 5, wherein when the pressure difference becomes equal to or smaller than a predetermined value, the first on-off valve is opened and the second on-off valve is closed. .
In the noise improvement control, the control device controls the outdoor expansion valve in the heating mode and reduces the pressure difference before and after the first on-off valve by stopping the compressor. 6. The first on-off valve is opened and the second on-off valve is closed when a difference is equal to or less than a predetermined value, or after a predetermined time has elapsed since the compressor was stopped. The air conditioning apparatus for vehicles described in 2.
A state in which the refrigerant opened from the outdoor heat exchanger is sucked into the compressor in the heating mode, and a state in which the refrigerant discharged from the outdoor heat exchanger is closed and flows to the heat absorber in the dehumidifying heating mode. A third on-off valve
In the noise improvement control, the control device opens the first on-off valve, closes the second on-off valve, and then a pressure difference before and after the third on-off valve becomes a predetermined value or less. 8. The vehicle air conditioner according to claim 5, wherein the third on-off valve is opened.
The said control apparatus increases the heat_generation | fever of the said auxiliary heating apparatus in the said noise improvement control, and opens the said 3rd on-off valve, Then, the heat generation of the said auxiliary heating apparatus is reduced. The vehicle air conditioning apparatus described.
10. The vehicle according to claim 9, wherein after the third on-off valve is opened, the control device reduces heat generation of the auxiliary heating device when the high-pressure side pressure becomes a predetermined value or more. Air conditioning equipment.