WO2018225486A1 - Air-conditioning device for vehicles - Google Patents

Abstract

Provided is an air-conditioning device for vehicles which is capable of eliminating the inconvenience of a compression malfunction occurring upon a compressor starting up when outside air temperature is low. The air-conditioning device for vehicles is provided with a compressor 2 and a control device 11 for controlling the rotation speed of the compressor 2 so as to be at a prescribed target rotation speed. An air-conditioning controller 20 of the control device 11 is provided with an outside air temperature sensor 33 for detecting the outside air temperature. In the event that the outside air temperature is no higher than a prescribed value at the time of the compressor 2 starting up, a heat pump controller 32 of the control device 11 executes control restricting the lower limit of the compressor rotation speed such that the target rotation speed of the compressor 2 is set to at least a prescribed lower rotation-speed limit A1.

Description

Air conditioner for vehicles

The present invention relates to a heat pump type vehicle air conditioner that air-conditions a vehicle interior.

Hybrid vehicles and electric vehicles have come into widespread use due to the emergence of environmental problems in recent years. And as an air conditioner that can be applied to such a vehicle, an electric compressor that compresses and discharges the refrigerant, a radiator that is provided on the vehicle interior side to dissipate the refrigerant, and on the vehicle interior side A heat absorber that absorbs the refrigerant and an outdoor heat exchanger that is provided outside the passenger compartment and dissipates or absorbs heat from the passenger compartment, dissipates the refrigerant discharged from the compressor in the radiator, and dissipates heat in the radiator A heating mode that absorbs heat in the outdoor heat exchanger, a dehumidifying heating mode in which the refrigerant discharged from the compressor dissipates heat in the radiator, and the refrigerant dissipated in the radiator absorbs heat in the heat absorber and the outdoor heat exchanger, The internal cycle mode in which the refrigerant discharged from the compressor is dissipated by a radiator, the refrigerant that has been radiated is depressurized, and heat is absorbed by a heat absorber, and the refrigerant discharged from the compressor is Heat is dissipated by the heat exchanger and outdoor heat exchanger, and after the decompressed refrigerant is depressurized, the dehumidifying and cooling mode in which heat is absorbed by the heat absorber, and the refrigerant discharged from the compressor is dissipated by the outdoor heat exchanger, and the heat is dissipated After the pressure of the refrigerant is reduced, a cooling mode in which each operation mode of the cooling mode in which heat is absorbed by the heat absorber is switched and executed has been developed (for example, see Patent Document 1).
For example, in the heating mode, the target rotational speed of the compressor is calculated based on the pressure of the radiator, which is the pressure on the high pressure side of the refrigerant circuit, and in the dehumidifying heating mode, based on the temperature of the heat absorber. The number of rotations of the compressor is controlled between a maximum number of rotations and a minimum number of rotations in a predetermined control so that the number of rotations becomes the same.

JP 2017-13652 A JP 2009-281279 A

Here, in the heating mode, for example, when the temperature in the passenger compartment is relatively high and the outside air temperature is low due to the influence of solar radiation or passengers, the target rotational speed when starting the compressor is the above-mentioned minimum rotational speed. Will increase. In addition, in the dehumidifying and heating mode, the target rotational speed is often the minimum rotational speed when the compressor is started in an environment where the outside air temperature is low due to the control by the temperature of the heat absorber. In such a heating mode or dehumidifying heating mode, when the compressor is started under a low outside air temperature environment, the density of the refrigerant sucked into the compressor becomes small, and it becomes difficult to form a compression chamber particularly when the rotation speed is low. The discharge pressure is difficult to increase. When such a state occurs, in addition to being unable to exhibit the required capability, there is a concern that abnormal noise may occur and internal damage may occur in the compressor because the operating state becomes abnormal.
For example, in the scroll type compressor described in the above-mentioned Patent Document 2, the scroll is pressed against the fixed scroll without using the back pressure. There was a problem that compression could not be achieved due to the inability to adhere to each other.
The present invention has been made to solve the conventional technical problem, and provides an air conditioner for a vehicle that can eliminate the disadvantage that compression failure occurs when the compressor is started at a low outside air temperature. The purpose is to provide.

An air conditioner for a vehicle according to the present invention includes a compressor that compresses a refrigerant, and a control device that controls the rotational speed of the compressor to a predetermined target rotational speed. An outside temperature sensor for detecting is provided. When the outside temperature is not more than a predetermined value at the time of starting the compressor, a compressor lower limit rotation speed limiting control is performed so that the target rotation speed of the compressor is not less than a predetermined lower limit rotation speed A1. It is characterized by doing.
The vehicle air conditioner according to a second aspect of the present invention is characterized in that, in the above invention, the control device has a minimum rotational speed A2 for control, and the lower limit rotational speed A1 is greater than the minimum rotational speed A2. To do.
According to a third aspect of the present invention, there is provided a vehicle air conditioner according to each of the first and second aspects of the present invention, wherein the control device starts the compressor lower limit rotation until a predetermined time t1 elapses after the rotation speed of the compressor is set as the target rotation speed. The number limiting control is continued.
According to a fourth aspect of the present invention, in the vehicle air conditioner of the present invention, the control device changes the direction to increase the lower limit rotational speed A1 and / or to increase the predetermined time t1 as the outside air temperature is lower. It is characterized by.
According to a fifth aspect of the present invention, there is provided a vehicle air conditioner that cools the air supplied to the vehicle interior by absorbing heat from the heat radiator that dissipates the refrigerant and heats the air supplied to the vehicle interior. And a heat exchanger that is provided outside the passenger compartment. The control device dissipates the refrigerant discharged from the compressor with a radiator and decompresses the radiated refrigerant. The vehicle interior is heated by absorbing heat with the heat exchanger, and a heating mode is calculated in which the target rotation speed of the compressor is calculated based on the pressure on the high pressure side, and the compressor lower limit rotation speed limit control is performed in this heating mode. It is characterized by performing.
According to a sixth aspect of the present invention, there is provided an air conditioner for a vehicle that cools air supplied to the vehicle interior by absorbing heat from the heat radiator that dissipates the refrigerant and heats the air supplied to the vehicle interior. A heat absorber, an outdoor heat exchanger provided outside the vehicle interior, and an auxiliary heating device for heating the air supplied to the vehicle interior, and the control device dissipates the refrigerant discharged from the compressor. Do not flow to the heater, let it flow to the outdoor heat exchanger to dissipate heat, depressurize the dissipated refrigerant, absorb heat with the heat absorber, and heat the auxiliary heating device to dehumidify and heat the interior of the vehicle, the temperature of the heat absorber The dehumidifying and heating mode for calculating the target rotational speed of the compressor is executed based on the above, and the compressor lower limit rotational speed limiting control is executed in the dehumidifying and heating mode.
According to a seventh aspect of the present invention, there is provided a vehicle air conditioner according to any one of the first to fifth aspects of the present invention, wherein the refrigerant dissipates heat and heats the air supplied to the vehicle interior, and the refrigerant absorbs heat into the vehicle interior. A heat absorber for cooling the air supplied to the vehicle and an outdoor heat exchanger provided outside the passenger compartment, and the control device causes the refrigerant discharged from the compressor to dissipate heat by the radiator and dissipates the refrigerant. After the pressure is reduced, the vehicle interior is dehumidified and heated by absorbing heat only with the heat absorber or with this heat absorber and the outdoor heat exchanger, and the target of the compressor is based on the pressure on the high pressure side or the temperature of the heat absorber. The dehumidifying and heating mode for calculating the rotation speed is executed, and the compressor lower limit rotation speed limiting control is executed in the dehumidifying and heating mode.

According to the present invention, in a vehicle air conditioner including a compressor that compresses a refrigerant and a control device that controls the rotational speed of the compressor to a predetermined target rotational speed, the control device detects an outside air temperature. An outside air temperature sensor is provided, and when the compressor is started, if the outside air temperature is equal to or lower than a predetermined value, compressor lower limit rotation speed limitation control is performed so that the target rotation speed of the compressor is equal to or higher than a predetermined lower limit rotation speed A1 Therefore, for example, when the compressor is started in the heating mode or the dehumidifying heating mode as in claims 5 to 7, the target rotational speed of the compressor is forcibly set to a lower limit in an environment where the outside air temperature is a predetermined value or less. The rotation speed is set to A1 or more.
This eliminates or suppresses inconvenience that the compressor falls into a poorly compressed state when starting up in a low outside air temperature environment and the required ability cannot be exhibited, and the problem that noise and durability deteriorate. Will be able to.
In this case, the lower limit rotational speed A1 is a value larger than the minimum rotational speed A2 in the control of the compressor as in the second aspect of the invention.
Then, after the start of the compressor, the control device continues the compressor lower limit rotation speed limit control until a predetermined time t1 elapses after the rotation speed of the compressor is set as the target rotation speed. Thus, it is possible to reliably eliminate the inconvenience caused by the compression failure state of the compressor.
Further, if the control device is changed to a direction in which the lower limit rotational speed A1 is increased and / or the predetermined time t1 is increased as the outside air temperature is lower as in the invention of claim 4, the minimum necessary The occurrence of inconvenience due to a change in the rotational speed of the compressor or a poorly compressed state of the compressor over time can be effectively eliminated.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram of the air conditioning apparatus for vehicles of one Embodiment to which this invention is applied (Example 1). It is a block diagram of the control apparatus of the air conditioning apparatus for vehicles of FIG. It is a schematic diagram of the airflow path of the vehicle air conditioner of FIG. It is a control block diagram regarding the compressor control in the heating mode of the heat pump controller of FIG. It is a control block diagram regarding the compressor control in the dehumidification heating mode of the heat pump controller of FIG. It is a control block diagram regarding auxiliary heater (auxiliary heating apparatus) control in the dehumidification heating mode of the heat pump controller of FIG. It is a flowchart explaining the compressor lower limit rotation speed limitation control by the heat pump controller of FIG. It is a figure which shows the change of TGNCh (TGNCc) at the time of the compressor starting by the heat pump controller of FIG. It is a block diagram of the air conditioning apparatus for vehicles of the other Example of this invention (Example 2).

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 (the thickest cooling mode) and the auxiliary heater single 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 passenger compartment of an electric vehicle, and includes an electric (battery-driven) compressor 2 that compresses refrigerant. The high-temperature and high-pressure refrigerant discharged from the compressor 2 flows in through the refrigerant pipe 13G and is dissipated to dissipate the vehicle. A radiator 4 as a heater for heating the air supplied to the room, an outdoor expansion valve 6 (pressure reducing device) composed of an electric valve that decompresses and expands the refrigerant during heating, and a heat radiator that is provided outside the vehicle compartment and is cooled. An indoor expansion valve 8 comprising an outdoor heat exchanger 7 that performs heat exchange between the refrigerant and the outside air to function as an evaporator during heating, and an electric valve (may be mechanical) that decompresses and expands the refrigerant. Decompressor) and air A heat absorber 9 that is provided in the passage 3 and absorbs heat from the outside of the vehicle interior during cooling and dehumidification to cool the air supplied to the vehicle interior and an accumulator 12 are sequentially connected by a refrigerant pipe 13. The refrigerant circuit R is configured. The refrigerant circuit R is filled with a predetermined amount of refrigerant and lubricating oil.
In addition, the compressor 2 of an Example is a scroll type compressor shown by the patent document 2 mentioned above. The outdoor heat exchanger 7 is provided with an outdoor blower 15, and the outdoor blower 15 forcibly ventilates the outside air through the outdoor heat exchanger 7 to exchange heat between the outside air and the refrigerant. Thereby, the outside air is ventilated to the outdoor heat exchanger 7 even when the vehicle is stopped (that is, the vehicle speed is 0 km / h).
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 an electromagnetic as an on-off valve that is opened during cooling or dehumidification. The refrigerant pipe 13 </ b> B on the refrigerant outlet side of the supercooling section 16 is connected to the refrigerant 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.
In addition, the refrigerant pipe 13B between the supercooling unit 16 and the indoor expansion valve 8 is provided in a heat exchange relationship with the refrigerant pipe 13C on the refrigerant 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 exchanges internal heat via an electromagnetic valve 21 as an on-off valve that is opened in the heating mode. The refrigerant pipe 13 </ b> C is connected to the downstream side of the vessel 19. Thus, the electromagnetic valve 21 is connected to the refrigerant outlet side of the outdoor heat exchanger 7, and the refrigerant outlet side of the heat absorber 9 is connected to the refrigerant outlet side of the electromagnetic valve 21. The refrigerant pipe 13 </ b> 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 13 </ b> E on the refrigerant outlet side of the radiator 4 is connected to the refrigerant inlet side of the outdoor heat exchanger 7 via the outdoor expansion valve 6.
A refrigerant pipe 13G between the refrigerant discharge side of the compressor 2 and the refrigerant inlet side of the radiator 4 is an electromagnetic valve 30 (a flow path switching device is configured as an on-off valve that is closed during dehumidifying heating and MAX cooling described later. ) Is provided. 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 an electromagnetic valve 40 as an on-off valve that is opened during dehumidifying heating and MAX cooling (also a flow path switching). Through the refrigerant pipe 13E on the refrigerant outlet side of the outdoor expansion valve 6 through the refrigerant pipe 13E.
That is, the bypass pipe 35 communicates the refrigerant discharge side of the compressor 2 and the refrigerant outlet side of the outdoor expansion valve 6, and is discharged from the compressor 2 when the electromagnetic valve 30 is closed and the electromagnetic valve 40 is opened. The flowed refrigerant is caused to flow directly into the outdoor heat exchanger 7 without flowing through the radiator 4 and the outdoor expansion valve 6. The bypass pipe 45, the electromagnetic valve 30, and the electromagnetic valve 40 constitute a bypass device 45.
Since the bypass device 45 is configured by the bypass pipe 35, the electromagnetic valve 30, and the electromagnetic valve 40, the refrigerant discharged from the compressor 2 is not allowed to flow to the radiator 4 and the outdoor expansion valve 6 as described later. It is possible to smoothly switch between the dehumidifying heating mode and the MAX cooling mode for directly flowing into the heat exchanger 7 and the heating mode, the dehumidifying cooling mode and the cooling mode for flowing the refrigerant discharged from the compressor 2 into the radiator 4. become able to.
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. Further, on the air downstream side of the suction switching damper 26, an indoor blower (blower fan) for supplying the introduced inside air or outside air (air supplied into the vehicle interior) to the air flow passage 3 and ventilating the heat absorber 9. ) 27 is provided.
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 in the air flow passage 3 which is on the windward side (air upstream side) of the radiator 4 with respect to the air flow in the air flow passage 3. Is provided. 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.
Here, the air flow passage 3 on the leeward side (air downstream side) from the heat absorber 9 of the HVAC unit 10 is partitioned by a partition wall 10A, and a heating heat exchange passage 3A and a bypass passage 3B that bypasses it are formed. The radiator 4 and the auxiliary heater 23 described above are disposed in the heating heat exchange passage 3A.
Further, the air (inside air or outside air) in the air flow passage 3 after flowing into the air flow passage 3 and passing through the heat absorber 9 is supplemented into the air flow passage 3 on the windward side of the auxiliary heater 23. An air mix damper 28 is provided for adjusting the rate of ventilation through the heating heat exchange passage 3A in which the heater 23 and the radiator 4 are disposed.
Further, the HVAC unit 10 on the leeward side of the radiator 4 includes a FOOT (foot) outlet 29A (first outlet) and a VENT (vent) outlet 29B (FOOT outlet 29A). For the outlet and the DEF outlet 29C, first outlets) and DEF (def) outlets 29C (second outlets) are formed. The FOOT air outlet 29A is an air outlet for blowing air under the feet in the passenger compartment, and is at the lowest position. Further, the VENT outlet 29B is an outlet for blowing out air near the driver's chest and face in the passenger compartment, and is located above the FOOT outlet 29A. The DEF air outlet 29C is an air outlet for blowing air to the inner surface of the windshield of the vehicle, and is located at the highest position above the other air outlets 29A and 29B.
The FOOT air outlet 29A, the VENT air outlet 29B, and the DEF air outlet 29C are respectively provided with a FOOT air outlet damper 31A, a VENT air outlet damper 31B, and a DEF air outlet damper 31C that control the amount of air blown out. It has been.
Next, FIG. 2 shows a block diagram of the control device 11 of the vehicle air conditioner 1 of the embodiment. The control device 11 includes an air-conditioning controller 20 and a heat pump controller 32 each of which is a microcomputer that is an example of a computer including a processor, and these include a CAN (Controller Area Network) and a LIN (Local Interconnect Network). Is connected to a vehicle communication bus 65. The compressor 2 and the auxiliary heater 23 are also connected to the vehicle communication bus 65, and the air conditioning controller 20, the heat pump controller 32, the compressor 2 and the auxiliary heater 23 are configured to transmit and receive data via the vehicle communication bus 65. Has been.
The air conditioning controller 20 is an upper controller that controls the air conditioning of the vehicle interior of the vehicle. The input of the air conditioning controller 20 detects an outside air temperature sensor 33 that detects the outside air temperature (Tam) of the vehicle and an outside air humidity. An outside air humidity sensor 34, an HVAC suction temperature sensor 36 that detects the temperature of the air (suction air temperature Tas) that is sucked into the air flow passage 3 from the suction port 25 and flows into the heat sink 9, and the air in the vehicle interior (inside air) An indoor air temperature sensor 37 that detects the temperature of the vehicle (indoor temperature Tin), an indoor air humidity sensor 38 that detects the humidity of the air in the vehicle interior, and an indoor CO that detects the carbon dioxide concentration in the vehicle interior ₂ Concentration sensor 39 and the temperature of the air blown into the passenger compartment
A blowout temperature sensor 41 to detect, a discharge pressure sensor 42 to detect the discharge refrigerant pressure (discharge pressure Pd) of the compressor 2, for example, a photosensor type solar radiation sensor 51 for detecting the amount of solar radiation into the passenger compartment, Each output of the vehicle speed sensor 52 for detecting the moving speed (vehicle speed) of the vehicle and an air conditioning (air conditioner) operation unit 53 for setting the set temperature and switching of the operation mode are connected.
The output of the air conditioning controller 20 is connected to an outdoor fan 15, an indoor fan 27, a suction switching damper 26, an air mix damper 28, and air outlet dampers 31A to 31C, which are controlled by the air conditioning controller 20. Is done.
The heat pump controller 32 is a controller that mainly controls the refrigerant circuit R. The input of the heat pump controller 32 includes a discharge temperature sensor 43 that detects a refrigerant temperature discharged from the compressor 2 and a suction refrigerant pressure of the compressor 2. A suction pressure sensor 44 that detects the refrigerant, a suction temperature sensor 55 that detects the suction refrigerant temperature Ts of the compressor 2, a radiator temperature sensor 46 that detects the refrigerant temperature (radiator temperature TCI) of the radiator 4, and a radiator 4, a radiator pressure sensor 47 for detecting the refrigerant pressure (radiator pressure PCI), a heat absorber temperature sensor 48 for detecting the refrigerant temperature (heat absorber temperature Te) of the heat absorber 9, and a refrigerant pressure of the heat absorber 9 are detected. A heat absorber pressure sensor 49 that detects the temperature of the auxiliary heater 23 (auxiliary heater temperature Tptc), and a refrigerant temperature at the outlet of the outdoor heat exchanger 7. Each of an outdoor heat exchanger temperature sensor 54 that detects (outdoor heat exchanger temperature TXO) and an outdoor heat exchanger pressure sensor 56 that detects refrigerant pressure (outdoor heat exchanger pressure PXO) at the outlet of the outdoor heat exchanger 7. The output is connected.
The output of the heat pump controller 32 includes an outdoor expansion valve 6, an indoor expansion valve 8, an electromagnetic valve 30 (for reheating), an electromagnetic valve 17 (for cooling), an electromagnetic valve 21 (for heating), and an electromagnetic valve 40 (bypass). Are connected to each other and are controlled by the heat pump controller 32. The compressor 2 and the auxiliary heater 23 each have a built-in controller, and the controllers of the compressor 2 and the auxiliary heater 23 send and receive data to and from the heat pump controller 32 via the vehicle communication bus 65. Be controlled.
The heat pump controller 32 and the air conditioning controller 20 transmit / receive data to / from each other via the vehicle communication bus 65, and control each device based on the output of each sensor and the setting input by the air conditioning operation unit 53. In the embodiment in this case, the outside air temperature sensor 33, the discharge pressure sensor 42, the vehicle speed sensor 52, the volumetric air volume Ga of air flowing into the air flow passage 3 (calculated by the air conditioning controller 20), and the air volume ratio SW ( The output from the air conditioning controller 53 is transmitted from the air conditioning controller 20 to the heat pump controller 32 via the vehicle communication bus 65, and is used for control by the heat pump controller 32.
Next, the operation of the vehicle air conditioner 1 having the above-described configuration will be described. In this embodiment, the control device 11 (the air conditioning controller 20 and the heat pump controller 32) has each operation mode of heating mode, dehumidifying heating mode, dehumidifying cooling mode, cooling mode, MAX cooling mode (maximum cooling mode), and auxiliary heater single mode. Switch and execute. 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 heat pump controller 32 (auto mode) or the manual operation (manual mode) to the air conditioning operation unit 53, the heat pump controller 32 opens the electromagnetic valve 21 (for heating) and the electromagnetic valve 17 (cooling). Close). Further, the electromagnetic valve 30 (for reheating) is opened, and the electromagnetic valve 40 (for bypass) is closed. Then, the compressor 2 is operated. The air conditioning controller 20 operates each of the blowers 15 and 27, and the air mix damper 28 basically heats all the air in the air flow passage 3 that is blown out from the indoor blower 27 and passes through the heat absorber 9 to the heat exchange passage 3A for heating. The auxiliary heater 23 and the radiator 4 are ventilated, but the air volume may be adjusted.
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. 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 outlets 29A to 29C, so that the vehicle interior is heated. become.
The heat pump controller 32 calculates the target radiator pressure PCO (target value of the radiator pressure PCI) from the target heater temperature TCO (target value of the radiator temperature TCI) calculated by the air conditioning controller 20 from the target outlet temperature TAO, and this target. The number of revolutions NC of the compressor 2 is controlled based on the radiator pressure PCO and the refrigerant pressure of the radiator 4 detected by the radiator pressure sensor 47 (radiator pressure PCI. Pressure on the high pressure side of the refrigerant circuit R) to radiate heat. The heating by the vessel 4 is controlled. Further, the heat pump controller 32 opens the outdoor expansion valve 6 based on the refrigerant temperature (radiator temperature TCI) of the radiator 4 detected by the radiator temperature sensor 46 and the radiator pressure PCI detected by the radiator pressure sensor 47. The degree of supercooling of the refrigerant at the outlet of the radiator 4 is controlled.
Further, in this heating mode, when the heating capability by the radiator 4 is insufficient with respect to the heating capability required for the cabin air conditioning, the heat pump controller 32 supplements the shortage with the heat generated by the auxiliary heater 23. The energization of the auxiliary 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 PTC 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 dehumidifying heating mode, the heat pump 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 is operated. The air conditioning controller 20 operates each of the blowers 15 and 27, and the air mix damper 28 basically heats all the air in the air flow passage 3 that is blown out from the indoor blower 27 and passes through the heat absorber 9 to the heat exchange passage 3A for heating. The auxiliary heater 23 and the radiator 4 are ventilated, but the air volume is also adjusted.
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 directly into the outdoor heat exchanger 7 without flowing into the radiator 4 and the outdoor expansion valve 6. 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 </ b> 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> 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 heat pump 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 heat pump controller 32 is a compressor based on the temperature of the heat absorber 9 (heat absorber temperature Te) detected by the heat absorber temperature sensor 48 and a target heat absorber temperature TEO that is a target value of the heat absorber temperature Te calculated by the air conditioning controller 20. 2, and the auxiliary heater temperature Tptc detected by the auxiliary heater temperature sensor 50 and the above-described target heater temperature TCO (in this case, the target value of the auxiliary heater temperature Tptc) is used. By controlling energization (heating by heat generation), the air temperature of the air blown out from the outlets 29A to 29C by the heating by the auxiliary heater 23 while appropriately cooling and dehumidifying the air in the heat absorber 9 is controlled. Prevent the decline accurately. 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.
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 heat pump 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 is operated. The air conditioning controller 20 operates each of the blowers 15 and 27, and the air mix damper 28 basically heats all the air in the air flow passage 3 that is blown out from the indoor blower 27 and passes through the heat absorber 9 to the heat exchange passage 3A for heating. The auxiliary heater 23 and the radiator 4 are ventilated, but the air volume is also adjusted.
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 </ b> 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> 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 heat pump controller 32 does not energize the auxiliary heater 23, so that the air that has been cooled and dehumidified 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). Is done. As a result, dehumidifying and cooling in the passenger compartment is performed.
The heat pump controller 32 determines the temperature 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 the target heat absorber temperature TEO (transmitted from the air conditioning controller 20) that is the target value. The rotational speed NC is controlled. The heat pump controller 32 calculates the target radiator pressure PCO from the target heater temperature TCO described above, and the target radiator pressure PCO and the refrigerant pressure (radiator pressure PCI) of the radiator 4 detected by the radiator pressure sensor 47. Based on the high pressure of the refrigerant circuit R), the valve opening degree of the outdoor expansion valve 6 is controlled, and heating by the radiator 4 is controlled.
(4) Cooling mode
Next, in the cooling mode, the heat pump controller 32 fully opens the opening degree of the outdoor expansion valve 6 in the dehumidifying and cooling mode. Then, the compressor 2 is operated and the auxiliary heater 23 is not energized. The air-conditioning controller 20 operates each of the blowers 15 and 27, and the air mix damper 28 is blown from the indoor blower 27 and the air in the air flow passage 3 that has passed through the heat absorber 9 is used as the auxiliary heater 23 in the heating heat exchange passage 3A. And it is set as the state which adjusts the ratio ventilated by the heat radiator 4. FIG.
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 </ b> 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> 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. Air that has been cooled and dehumidified by the heat absorber 9 is blown into the vehicle interior from each of the air outlets 29A to 29C (partly passes through the radiator 4 to exchange heat), thereby cooling the vehicle interior. Will be done. Further, in this cooling mode, the heat pump controller 32 uses the temperature of the heat absorber 9 (heat absorber temperature Te) detected by the heat absorber temperature sensor 48 and the above-described target heat absorber temperature TEO which is the target value of the compressor 2. The number of revolutions NC is controlled.
(5) MAX cooling mode (maximum cooling mode)
Next, in the MAX cooling mode (maximum cooling mode), the heat pump 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 is operated and the auxiliary heater 23 is not energized. The air conditioning controller 20 operates each of the blowers 15 and 27, and the air mix damper 28 is blown from the indoor blower 27 and the air in the air flow passage 3 passing through the heat absorber 9 is used as an auxiliary heater for the heating heat exchange passage 3 </ b> A. 23 and the rate of ventilation through the radiator 4 are adjusted.
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 directly into the outdoor heat exchanger 7 without flowing into the radiator 4 and the outdoor expansion valve 6. 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 </ b> 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> 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 heat pump controller 32 is also connected to the compressor 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, which is the target value. 2 is controlled.
(6) Auxiliary heater single mode
Note that the control device 11 of the embodiment stops the compressor 2 and the outdoor blower 15 of the refrigerant circuit R and energizes the auxiliary heater 23 when, for example, excessive frost formation occurs in the outdoor heat exchanger 7. The auxiliary heater single mode for heating the passenger compartment with only 23 is provided. Also in this case, the heat pump controller 32 controls energization (heat generation) of the auxiliary heater 23 based on the auxiliary heater temperature Tptc detected by the auxiliary heater temperature sensor 50 and the target heater temperature TCO described above.
The air conditioning controller 20 operates the indoor blower 27, and the air mix damper 28 passes the air in the air flow passage 3 blown out from the indoor blower 27 to the auxiliary heater 23 of the heat exchange passage 3A for heating, and the air volume is reduced. The state to be adjusted. Since the air heated by the auxiliary heater 23 is blown into the vehicle interior from each of the air outlets 29A to 29C, the vehicle interior is thereby heated.
(7) Switching operation mode
The air conditioning controller 20 calculates the target blowing temperature TAO described above from the following formula (I). This target blowing temperature TAO is a target value of the temperature of the air blown into the passenger compartment.
TAO = (Tset−Tin) × K + Tbal (f (Tset, SUN, Tam))
.. (I)
Here, Tset is a set temperature in the passenger compartment set by the air conditioning operation unit 53, Tin is a room temperature detected by the inside air temperature sensor 37, K is a coefficient, Tbal is a set temperature Tset, and a solar radiation amount detected by the solar radiation sensor 51. SUN is a balance value calculated from the outside air temperature Tam detected by the outside air temperature sensor 33. And generally this target blowing temperature TAO is so high that the outside temperature Tam is low, and it falls as the outside temperature Tam rises.
When the heat pump controller 32 is activated, the heat pump controller 32 determines which one of the above operation modes based on the outside air temperature Tam (detected by the outside air temperature sensor 33) transmitted from the air conditioning controller 20 via the vehicle communication bus 65 and the target outlet temperature TAO. The operation mode is selected and each operation mode is transmitted to the air conditioning controller 20 via the vehicle communication bus 65.
In addition, the heat pump controller 32, after startup, the outside air temperature Tam, the humidity in the vehicle interior, the target blowing temperature TAO, the heating temperature TH (the temperature of the air on the leeward side of the radiator 4), the target heater temperature TCO, By switching each operation mode based on parameters such as the endothermic temperature Te, the target endothermic temperature TEO, whether there is a dehumidification request in the passenger compartment, the heating mode accurately according to the environmental conditions and the necessity of dehumidification, Dehumidifying heating mode, dehumidifying cooling mode, cooling mode, MAX cooling mode and auxiliary heater single mode are switched to control the temperature of the air blown into the passenger compartment to the target outlet temperature TAO, realizing comfortable and efficient passenger compartment air conditioning To do.
(8) Control of the compressor 2 in the heating mode by the heat pump controller 32
Next, the control of the compressor 2 in the heating mode described above will be described in detail with reference to FIG. FIG. 4 is a control block diagram of the heat pump controller 32 that determines the target rotational speed (compressor target rotational speed) TGNCh of the compressor 2 for heating mode. The F / F (feed forward) manipulated variable calculation unit 58 of the heat pump controller 32 has an outside air temperature Tam obtained from the outside air temperature sensor 33, a blower voltage BLV of the indoor blower 27, and SW = (TAO−Te) / (TH−Te). ) Obtained by the air mix damper 28, the target supercooling degree TGSC that is the target value of the supercooling degree SC at the outlet of the radiator 4, and the target heater that is the target value of the temperature of the radiator 4 described above. Based on the temperature TCO (transmitted from the air conditioning controller 20) and the target radiator pressure PCO that is the target value of the pressure of the radiator 4, the F / F manipulated variable TGNChff of the compressor target rotational speed is calculated.
Here, the above-mentioned TH for calculating the air volume ratio SW is the temperature of the leeward air of the radiator 4 (hereinafter referred to as the heating temperature), and the heat pump controller 32 calculates the first-order lag calculation formula (II) shown below. presume.
TH = (INTL × TH0 + Tau × THz) / (Tau + INTL) (II)
Here, INTL is the calculation cycle (constant), Tau is the time constant of the primary delay, TH0 is the steady value of the heating temperature TH in the steady state before the primary delay calculation, and THz is the previous value of the heating temperature TH. By estimating the heating temperature TH in this way, there is no need to provide a special temperature sensor.
The heat pump controller 32 changes the time constant Tau and the steady value TH0 according to the operation mode described above, thereby making the above-described estimation formula (II) different depending on the operation mode, and estimates the heating temperature TH. The heating temperature TH is transmitted to the air conditioning controller 20 via the vehicle communication bus 65.
The target radiator pressure PCO is calculated by the target value calculator 59 based on the target subcooling degree TGSC and the target heater temperature TCO. Further, the F / B (feedback) manipulated variable calculation unit 60 performs the compressor target rotation based on the target radiator pressure PCO and the radiator pressure PCI (pressure on the high pressure side of the refrigerant circuit R) that is the refrigerant pressure of the radiator 4. The F / B manipulated variable TGNChfb is calculated. Then, the F / F manipulated variable TGNCnff computed by the F / F manipulated variable computing unit 58 and the F / B manipulated variable TGNChfb computed by the F / B manipulated variable computing unit 60 are added by the adder 61, and the limit setting unit 62 After limiting the minimum control speed ECNpdLimLo (hereinafter referred to as A2) and the maximum control speed ECNpdLimHi, the compressor target speed TGNCh is determined. In the heating mode, the heat pump controller 32 controls the rotational speed NC of the compressor 2 based on the compressor target rotational speed TGNCh.
(9) Control of the compressor 2 and the auxiliary heater 23 in the dehumidifying heating mode by the heat pump controller 32
On the other hand, FIG. 5 is a control block diagram of the heat pump controller 32 that determines the target rotational speed (compressor target rotational speed) TGNCc of the compressor 2 for the dehumidifying and heating mode. The F / F manipulated variable calculation unit 63 of the heat pump controller 32 is a target heat release that is a target value of the outside air temperature Tam, the volumetric air volume Ga of the air flowing into the air flow passage 3, and the pressure of the radiator 4 (radiator pressure PCI). Based on the compressor pressure PCO and the target heat absorber temperature TEO which is the target value of the temperature of the heat absorber 9 (heat absorber temperature Te), the F / F manipulated variable TGNCcff of the compressor target rotational speed is calculated.
Further, the F / B operation amount calculation unit 64 calculates the F / B operation amount TGNCcfb of the compressor target rotational speed based on the target heat absorber temperature TEO (transmitted from the air conditioning controller 20) and the heat absorber temperature Te. Then, the F / F manipulated variable TGNCcff computed by the F / F manipulated variable computing unit 63 and the F / B manipulated variable TGNCcfb computed by the F / B manipulated variable computing unit 64 are added by the adder 66, and the limit setting unit 67 After the control minimum rotational speed TGNCcLimLo (hereinafter referred to as A2) and the maximum control rotational speed TGNCcLimHi are set, the compressor target rotational speed TGNCc is determined. In the dehumidifying and heating mode, the heat pump controller 32 controls the rotational speed NC of the compressor 2 based on the compressor target rotational speed TGNCc.
FIG. 6 is a control block diagram of the heat pump controller 32 that determines the auxiliary heater required capacity TGQPTC of the auxiliary heater 23 in the dehumidifying heating mode. The subtractor 73 of the heat pump controller 32 receives the target heater temperature TCO and the auxiliary heater temperature Tptc, and calculates a deviation (TCO−Tptc) between the target heater temperature TCO and the auxiliary heater temperature Tptc. This deviation (TCO-Tptc) is input to the F / B control unit 74. The F / B control unit 74 eliminates the deviation (TCO-Tptc) so that the auxiliary heater temperature Tptc becomes the target heater temperature TCO. The required capacity F / B manipulated variable is calculated.
The auxiliary heater required capacity F / B manipulated variable calculated by the F / B control unit 74 is set by the limit setting unit 76 after the limit of the control lower limit value QptcLimLo and the control upper limit value QptcLimHi are set. Determined as capability TGQPTC. In the dehumidifying heating mode, the controller 32 controls energization of the auxiliary heater 23 based on the auxiliary heater required capacity TGQPTC, thereby generating heat (heating) of the auxiliary heater 23 so that the auxiliary heater temperature Tptc becomes the target heater temperature TCO. To control.
Thus, in the dehumidifying heating mode, the heat pump controller 32 controls the operation of the compressor based on the heat absorber temperature Te and the target heat absorber temperature TEO, and controls the heat generation of the auxiliary heater 23 based on the target heater temperature TCO. Thus, cooling and dehumidification by the heat absorber 9 and heating by the auxiliary heater 23 in the dehumidifying heating mode are accurately controlled. As a result, it is possible to control the temperature to a more accurate heating temperature while more appropriately dehumidifying the air blown into the passenger compartment, thereby realizing more comfortable and efficient dehumidifying heating in the passenger compartment. Will be able to.
(10) Control of the air mix damper 28
Next, the control of the air mix damper 28 by the air conditioning controller 20 will be described with reference to FIG. In FIG. 3, Ga is the volumetric volume of the air flowing into the air flow passage 3 described above, Te is the heat absorber temperature, and TH is the heating temperature described above (the temperature of the air on the leeward side of the radiator 4).
The air conditioning controller 20 is based on the air volume ratio SW that is passed through the radiator 4 and the auxiliary heater 23 in the heating heat exchange passage 3A calculated by the above-described expression (the following expression (III)) so that the air volume of the ratio is obtained. Further, by controlling the air mix damper 28, the amount of ventilation to the radiator 4 (and the auxiliary heater 23) is adjusted.
SW = (TAO-Te) / (TH-Te) (III)
That is, the air flow rate ratio SW passing through the radiator 4 and the auxiliary heater 23 in the heat exchange passage 3A for heating changes in a range of 0 ≦ SW ≦ 1, and when “0”, the air is not passed through the heat exchange passage 3A for heating. The air mix fully closed state in which all the air in the air flow passage 3 is passed through the bypass passage 3B, and the air mix fully open state in which all the air in the air flow passage 3 is passed through the heating heat exchange passage 3A with "1" It becomes. That is, the air volume to the radiator 4 is Ga × SW.
(11) Compressor lower limit rotation speed limit control in heating mode and dehumidifying heating mode
Next, referring to FIG. 7 and FIG. 8, when the operation mode of the vehicle air conditioner 1 is the heating mode and the dehumidifying heating mode described above, the compressor lower limit rotation speed limit control executed by the heat pump controller 32 is performed. An example will be described. As described above, when the compressor 2 is started in the heating mode or the dehumidifying heating mode, a compression failure of the compressor 2 is likely to occur in an environment where the outside air temperature Tam is low. Therefore, the heat pump controller 32 executes the control described below when the compressor 2 is started in the heating mode or the dehumidifying heating mode.
That is, when the vehicle air conditioner 1 is activated (vehicle activation), the heat pump controller 32 resets a flag and a timer, which will be described later, and then a compressor lower limit rotational speed restriction control flag, which will be described later in step S1 of FIG. It is determined whether fNCLLim has been reset. Since it has been reset at this point, it is next determined whether or not the compressor 2 has been started in step S2. If it is assumed that the vehicle air conditioner 1 (vehicle) is currently activated or restarted after the compressor 2 is temporarily stopped, the heat pump controller 32 determines that the compressor 2 is activated. And it progresses to step S3 and it is judged whether the present operation mode is heating mode or dehumidification heating mode which were mentioned above.
And when it is at the time of starting of the compressor 2 in heating mode or dehumidification heating mode, the heat pump controller 32 progresses to step S4 from step S2, S3, and the external temperature Tam transmitted from the air-conditioning controller 20 is predetermined value T1 (for example, 10 ° C.) or less. When the outside air temperature Tam is a low environment equal to or lower than the predetermined value T1 when the compressor 2 is started, the heat pump controller 32 proceeds from step S4 to step S5, and sets the above-described flag (compressor lower limit rotation speed limit control flag) fNCLLim. Set and start the compressor lower limit rotation speed limit control.
Next, the heat pump controller 32 proceeds to step S6, and as described above, the compressor target rotation speed TGNCh calculated in the heating mode (FIG. 4) or the compressor target rotation speed TGNCc calculated in the dehumidifying heating mode (FIG. 5). In any case, it is determined whether or not the target rotational speed of the compressor 2 is lower than a predetermined lower limit rotational speed A1. The lower limit rotation speed A1 is set to a value greater than at least the above-described minimum control rotation speed A2 (ECNpdLimLo in the heating mode, TGNCcLimLo in the dehumidifying heating mode. Both are 800 rpm in the embodiment), and 1500 rpm in the embodiment.
If the compressor target rotational speeds TGNCh and TGNCh calculated in FIGS. 4 and 5 are lower than the lower limit rotational speed A1 (for example, 800 rpm), the heat pump controller 32 proceeds to step S7, and the compressor target rotational speed TGNCh Or TGNCc is forcibly increased to the lower limit rotational speed A1 (1500 rpm).
When the compressor target rotational speeds TGNCh and TGNCc calculated in FIGS. 4 and 5 are higher than the lower limit rotational speed A1, for example, 3000 rpm, the heat pump controller 32 proceeds to step S8, which will be described later, instead of step S7. Therefore, the compressor target rotational speeds TGNCh and TGNCc are set to the calculated 3000 rpm. That is, the heat pump controller 32 restricts the compressor target rotational speeds TGNCh and TGNCc from becoming lower than the lower limit rotational speed A1, and prevents the compressor from entering a poorly compressed state by making it equal to or higher than the lower limit rotational speed A1.
The heat pump controller 32 next starts the compressor 2 in step S8, and after setting the rotational speed NC of the compressor 2 to the target rotational speed TGNCh or TGNCc (target rotational speeds TGNCh, TGNCc greater than the lower limit rotational speed A1) for a predetermined time. It is determined whether t1 has elapsed. The predetermined time t1 is set to 10 seconds in the embodiment, and the elapsed time is measured by a timer that the heat pump controller 32 has as its function.
If it is assumed that the predetermined time t1 has not elapsed since the rotational speed NC of the compressor 2 is set to the target rotational speed TGNCh or TGNCc (more than the lower limit rotational speed A1) at the present time, the heat pump controller 32 performs other control from step S8. The process returns to step S1 again. However, since the flag fNCLLim is set at this time, the process proceeds from step S1 to step S6. Thereafter, the compressor target rotational speeds TGNCh and TGNCc calculated in FIGS. 4 and 5 are lower than the lower limit rotational speed A1. As long as it is low, the heat pump controller 32 proceeds to step S7 to forcibly increase the compressor target rotational speeds TGNCh, TGNCc to the lower limit rotational speed A1, and if the compressor target rotational speeds TGNCh, TGNCc are equal to or higher than the lower limit rotational speed A1, The compressor target rotation speeds are TGNCh and TGNCc.
When a predetermined time t1 (10 seconds) has elapsed since the rotation speed NC of the compressor 2 is set to the target rotation speed TGNCh or TGNCc (more than the lower limit rotation speed A1), the heat pump controller 32 proceeds from step S8 to step S9, and the flag fNCLLim To reset. As a result, the compressor lower limit rotational speed restriction control is terminated, and thereafter, the process proceeds from step S1 to step S2. If the present time is not when the compressor 2 is started, the process does not proceed from step S3. Therefore, the rotation speed NC of the compressor 2 is determined by the F / F operation amount TGNCnff calculated by the F / F operation amount calculation unit 58 of FIG. 4 and the F / B operation amount calculated by the F / B operation amount calculation unit 60. Compressor target rotation speed TGNCh (heating mode) obtained by adding TGNChfb, F / F operation amount TGNCcff and F / B operation amount calculation unit 64 calculated by F / F operation amount calculation unit 63 in FIG. It is controlled by the compressor target rotational speed TGNCc (dehumidification heating mode) obtained by adding the F / B manipulated variable TGNCcfb.
This is shown in FIG. In addition, the vertical axis | shaft of FIG. 8 is compressor target rotation speed TGNCh and TGNCc, and a horizontal axis is time. When starting in the heating mode or the dehumidifying heating mode, the compressor target rotational speeds TGNCh and TGNCc calculated in FIGS. 4 and 5 are set to the minimum rotational speed A2 (from the lower limit rotational speed A1 as shown by a thick broken line in FIG. 8, for example). In the case of a low value), the heat pump controller 32 increases the compressor target rotational speeds TGNCh and TGNCc to the lower limit rotational speed A1, and sets the rotational speed NC to a predetermined value from the start of the compressor 2 as shown by a thick solid line in FIG. Increase at the rate of increase to the lower limit rotational speed A1.
The compressor target rotational speed TGNCh calculated in FIG. 4 and FIG. 5 until the predetermined time t1 elapses after the rotational speed NC of the compressor 2 is set to the compressor target rotational speed TGNCh or TGNCh (lower limit rotational speed A1). As long as TGNCc is lower than the lower limit rotational speed A1, the compressor target rotational speeds TGNCh and TGNCc are maintained at the lower limit rotational speed A1, and after the predetermined time t1 has elapsed, the compressor target rotational speed calculated in FIG. 4 and FIG. The minimum rotational speed A2 that is TGNCh or TGNCc is set, and the rotational speed NC of the compressor 2 is lowered to the compressor target rotational speed TGNCh or TGNCc (minimum rotational speed A2) (indicated by AUTO in FIG. 8).
(11-1) Change control of lower limit rotational speed A1 and predetermined time t1
Here, since the compression failure state of the compressor 2 is more likely to occur as the outside air temperature Tam is lower, the heat pump controller 32 increases the lower limit rotational speed A1 as the outside air temperature Tam is lower in the embodiment. change. For example, when the outside air temperature Tam is in the range of 0 ° C. ≦ Tam <10 ° C. lower than the predetermined value T1 (10 ° C.) of the embodiment, the heat pump controller 32 has a lower limit rotational speed A1 higher than 1500 rpm of the above-described embodiment. When the outside air temperature Tam is lower than 0 ° C., for example, the lower limit rotational speed A1 is set to 2000 rpm, for example. Such a change may be performed stepwise as described above, or may be changed linearly according to a change in the outside air temperature Tam.
For the same reason, in the embodiment, the heat pump controller 32 changes the direction in which the predetermined time t1 is increased as the outside air temperature Tam is lower. For example, when the outside air temperature Tam is in the range of 0 ° C. ≦ Tam <10 ° C. lower than the predetermined value T1 (10 ° C.) of the embodiment, the heat pump controller 32 sets the predetermined time t1 higher than 10 seconds of the above-described embodiment. When the outside air temperature Tam is lower than 0 ° C., for example, the predetermined time t1 is set to 20 seconds, for example. Such a change may be a stepwise change as described above, or may be a linear change according to a change in the outside air temperature Tam. In the above embodiment, both the lower limit rotational speed A1 and the predetermined time t1 are changed according to the outside air temperature Tam. However, the present invention is not limited to this, and only one of them may be changed.
As described above, in the present invention, the air-conditioning controller 20 configuring the control device 11 includes the outside air temperature sensor 33 that detects the outside air temperature Tam, and the heat pump controller 32 configuring the control device 11 is configured to open the outside air when the compressor 2 is started. When the temperature Tam is equal to or lower than the predetermined value T1, the compressor lower limit rotational speed restriction control is performed so that the target rotational speeds TGNCh and TGNCc of the compressor 2 are equal to or higher than the predetermined lower limit rotational speed A1, so for example, heating When the compressor 2 is started in the mode or the dehumidifying heating mode, the target rotational speeds TGNCh and TGNCc of the compressor 2 are forcibly set to the lower limit rotational speed A1 or more in an environment where the outside air temperature Tam is equal to or lower than the predetermined value T1. Become.
As a result, the compressor 2 falls into a poorly compressed state at the time of start-up in a low outside air temperature environment, and the problem that the required capacity cannot be exhibited and the problem that noise and durability are deteriorated are obviated or suppressed. Will be able to. In this case, the lower limit rotational speed A1 is larger than the minimum rotational speed A2 in the control of the compressor 2.
Then, in the embodiment, after the compressor 2 is started, the heat pump controller 32 sets the rotation speed NC of the compressor 2 to the target rotation speeds TGNCh and TGNCc (lower limit rotation speed A1 or more) until a predetermined time t1 elapses. Since the rotation speed limit control is continued, it is possible to reliably eliminate the occurrence of inconvenience due to the compression failure state of the compressor 2.
In the embodiment, the heat pump controller 32 changes the direction to increase the lower limit rotational speed A1 and / or to increase the predetermined time t1 as the outside air temperature Tam is lower. It becomes possible to effectively eliminate the occurrence of inconvenience due to the change in the number or the compression failure state of the compressor 2 over time.

Next, FIG. 9 shows a configuration diagram of a vehicle air conditioner 1 of another embodiment to which the present invention is applied. In this figure, the same reference numerals as those in FIG. 1 indicate the same or similar functions. In the case of this embodiment, the outlet of the supercooling section 16 is connected to the check valve 18, and the outlet of the check valve 18 is connected to the refrigerant pipe 13B. The check valve 18 has a forward direction on the refrigerant pipe 13B (indoor expansion valve 8) side.
A refrigerant pipe 13E on the refrigerant outlet side of the radiator 4 is branched in front of the outdoor expansion valve 6. This branched refrigerant pipe (hereinafter referred to as a second bypass pipe) 13F is an electromagnetic valve 22 (for dehumidification). Is connected to the refrigerant pipe 13B on the downstream side of the check valve 18 via the on-off valve. Further, the refrigerant pipe 13C on the refrigerant outlet side of the heat absorber 9 is connected to an evaporation pressure adjusting valve 70 on the refrigerant downstream side of the internal heat exchanger 19 and upstream of the refrigerant from the junction with the refrigerant pipe 13D. Yes. The electromagnetic valve 22 and the evaporation pressure adjusting valve 70 are also connected to the output of the heat pump controller 32. Note that the bypass device 45 including the bypass pipe 35, the electromagnetic valve 30, and the electromagnetic valve 40 in FIG. 1 of the above-described embodiment is not provided. Others are the same as in FIG.
With the above configuration, the operation of the vehicle air conditioner 1 of this embodiment will be described. In this embodiment, the heat pump controller 32 switches between the heating mode, the dehumidifying heating mode, the internal cycle mode, the dehumidifying cooling mode, the cooling mode, and the auxiliary heater single mode (the MAX cooling mode is present in this embodiment). do not do). The operation when the heating mode, the dehumidifying and cooling mode, and the cooling mode are selected, the refrigerant flow, and the auxiliary heater single mode are the same as those in the above-described embodiment (embodiment 1), and thus the description thereof is omitted. However, in this embodiment (Example 2), the solenoid valve 22 is closed in the heating mode, the dehumidifying cooling mode, and the cooling mode.
(12) Dehumidifying and heating mode of vehicle air conditioner 1 of FIG. 9 On the other hand, when the dehumidifying and heating mode is selected, in this embodiment (Example 2), heat pump controller 32 opens electromagnetic valve 21 (for heating). The electromagnetic valve 17 (for cooling) is closed. Further, the electromagnetic valve 22 (for dehumidification) is opened. Then, the compressor 2 is operated. The air conditioning controller 20 operates each of the blowers 15 and 27, and the air mix damper 28 basically heats all the air in the air flow passage 3 that is blown out from the indoor blower 27 and passes through the heat absorber 9 to the heat exchange passage 3A for heating. The auxiliary heater 23 and the radiator 4 are ventilated, but the air volume is also adjusted.
Thereby, the high-temperature and high-pressure gas refrigerant discharged from the compressor 2 flows into the radiator 4 from the refrigerant pipe 13G. Since the air in the air flow path 3 that has flowed into the heat exchange path 3A for heating is passed through the heat radiator 4, the air in the air flow path 3 is heated by the high-temperature refrigerant in the heat radiator 4, while the heat radiator The refrigerant in 4 is deprived of heat by the air and cooled to condense.
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 through the refrigerant pipe 13C through the refrigerant pipe 13A, the solenoid valve 21 and the refrigerant pipe 13D, and is gas-liquid separated there. Repeated circulation inhaled.
Further, a part of the condensed refrigerant flowing through the refrigerant pipe 13E through the radiator 4 is diverted, passes through the electromagnetic valve 22, and reaches the indoor expansion valve 8 through the internal heat exchanger 19 from the second bypass pipe 13F and the refrigerant pipe 13B. It becomes like this. 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 sequentially passes through the internal heat exchanger 19 and the evaporation pressure adjusting valve 70 and then merges with the refrigerant from the refrigerant pipe 13D in the refrigerant pipe 13C. Then, the refrigerant is sucked into the compressor 2 through the accumulator 12. repeat. Since the air dehumidified by the heat absorber 9 is reheated in the process of passing through the radiator 4, dehumidifying heating in the passenger compartment is thereby performed.
The heat pump controller 32 selects the smaller one of the compressor target rotational speed TGNCh calculated in FIG. 4 and the compressor target rotational speed TGNCh calculated in FIG. 5 to control the rotational speed NC of the compressor 2. To do. Further, the heat pump 32 increases the valve opening degree of the outdoor expansion valve 6 based on the temperature Te of the heat absorber 9 detected by the heat absorber temperature sensor 48 and the target heat absorber temperature TEO transmitted from the air conditioning controller 20 (for control purposes). Simple control is performed in two stages, ie, the maximum opening) and the small diameter (minimum opening for control). Further, the heat pump controller 32 opens (enlarges the flow path) / closes (flows a small amount of refrigerant) the heat absorber 9 based on the temperature Te of the heat absorber 9 detected by the heat absorber temperature sensor 48. The inconvenience of freezing due to too low temperature is prevented.
(13) Internal cycle mode of the vehicle air conditioner 1 of FIG. 9 In the internal cycle mode, the heat pump controller 32 fully closes the outdoor expansion valve 6 in the state of the dehumidifying heating mode (fully closed position), The solenoid valve 21 is closed. Since the outdoor expansion valve 6 and the electromagnetic valve 21 are closed, the inflow of refrigerant to the outdoor heat exchanger 7 and the outflow of refrigerant from the outdoor heat exchanger 7 are blocked. The condensed refrigerant flowing through the refrigerant pipe 13E through the refrigerant flows through the electromagnetic valve 22 to the second bypass pipe 13F. The refrigerant flowing through the second bypass pipe 13F reaches the indoor expansion valve 8 via the internal heat exchanger 19 from the refrigerant pipe 13B. 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 sequentially flows through the refrigerant pipe 13C through the internal heat exchanger 19 and the evaporation pressure adjustment valve 70, and repeats circulation that is sucked into the compressor 2 through the accumulator 12. Since the air dehumidified by the heat absorber 9 is reheated in the process of passing through the radiator 4, dehumidifying heating in the passenger compartment is thereby performed. Since the refrigerant is circulated between the radiator 4 (radiation) and the heat absorber 9 (heat absorption) in the passage 3, heat from the outside air is not pumped up, and heating for the consumed power of the compressor 2 is performed. Ability is demonstrated. Since the entire amount of the refrigerant flows through the heat absorber 9 that exhibits the dehumidifying action, the dehumidifying capacity is higher than that in the dehumidifying and heating mode, but the heating capacity is lowered.
And since the heat pump controller 32 controls the compressor 2, the outdoor expansion valve 6, and the evaporation pressure regulating valve 70 similarly to the said dehumidification heating mode, this internal cycle mode can also be considered as a part of dehumidification heating mode.
(14) Compressor lower limit rotation speed limit control in heating mode and dehumidifying heating mode And also in this embodiment, when starting up the compressor 2 in the heating mode and dehumidifying heating mode (including the internal cycle mode), the heat pump controller 32 The compressor lower limit rotational speed limit control similar to (11) of the above-described embodiment is executed, and the lower limit rotational speed A1 and the predetermined time t1 are changed similarly to (11-1).
As described above, even in the dehumidifying and heating mode of this embodiment, the target number of rotations (TGNCh, TGNCc) of the compressor 2 is controlled based on the high-pressure side pressure and the temperature of the heat absorber temperature Te. Although it is likely to be in a poorly compressed state at the start-up in a temperature environment, the compressor 2 falls into a poorly-compressed state at the start-up in a low outside air temperature environment by executing the compressor lower limit rotation speed limit control, which is required. Inconvenience that the ability to perform the function cannot be exhibited, and the problem that noise and durability are deteriorated can be solved or suppressed in advance.
It should be noted that the numerical values shown in the embodiments are not limited thereto, and should be appropriately set according to the apparatus to be applied. Further, the auxiliary heating device is not limited to the auxiliary heater 23 shown in the embodiment, and a heat medium circulation circuit that heats the air in the air flow passage 3 by circulating the heat medium heated by the heater or an engine. You may utilize the heater core etc. which circulate through the heated radiator water.

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 11 Control apparatus 20 Air conditioning controller 23 Auxiliary heater (auxiliary heating apparatus)
27 Indoor blower
32 heat pump controller 33 outside temperature sensor 65 vehicle communication bus R refrigerant circuit

Claims (7)

1. In a vehicle air conditioner including a compressor that compresses a refrigerant, and a control device that controls the rotational speed of the compressor to a predetermined target rotational speed,
   The control device includes an outside air temperature sensor that detects an outside air temperature. When the outside air temperature is equal to or lower than a predetermined value when the compressor is started, the target rotation speed of the compressor is set to a predetermined lower limit rotation speed A1 or more. An air conditioner for a vehicle that performs compressor lower limit rotational speed restriction control.
2. 2. The vehicle air conditioner according to claim 1, wherein the control device has a minimum rotational speed A2 for control, and the lower limit rotational speed A1 is larger than the minimum rotational speed A2.
3. The said control apparatus continues the said compressor lower limit rotation speed limitation control until predetermined time t1 passes after making the rotation speed of the said compressor into the said target rotation speed after starting of the said compressor. The vehicle air conditioner according to claim 1 or 2.
4. 4. The vehicle air according to claim 3, wherein the control device changes the direction to increase the lower limit rotational speed A <b> 1 and / or to increase the predetermined time t <b> 1 as the outside air temperature is lower. Harmony device.
5. A radiator for heating the air supplied to the passenger compartment by dissipating the refrigerant;
   A heat absorber for absorbing the refrigerant to cool the air supplied to the vehicle interior;
   An outdoor heat exchanger provided outside the vehicle compartment,
   The control device radiates the refrigerant discharged from the compressor with the radiator, depressurizes the radiated refrigerant, heats the vehicle interior by absorbing heat with the outdoor heat exchanger, A heating mode for calculating a target rotational speed of the compressor based on the pressure on the side, and
   The vehicle air conditioner according to any one of claims 1 to 4, wherein the compressor lower limit rotation speed limit control is executed in the heating mode.
6. A radiator for heating the air supplied to the passenger compartment by dissipating the refrigerant;
   A heat absorber for absorbing the refrigerant to cool the air supplied to the vehicle interior;
   An outdoor heat exchanger installed outside the passenger compartment,
   An auxiliary heating device for heating the air supplied to the vehicle interior,
   The control device does not flow the refrigerant discharged from the compressor to the radiator, but flows it to the outdoor heat exchanger to radiate heat, depressurizes the radiated refrigerant, and then absorbs heat by the heat absorber. While dehumidifying and heating the vehicle interior by causing the auxiliary heating device to generate heat, executing a dehumidifying heating mode that calculates a target rotational speed of the compressor based on the temperature of the heat absorber,
   The vehicle air conditioner according to any one of claims 1 to 5, wherein the compressor lower limit rotation speed restriction control is executed in the dehumidifying heating mode.
7. A radiator for heating the air supplied to the passenger compartment by dissipating the refrigerant;
   A heat absorber for absorbing the refrigerant to cool the air supplied to the vehicle interior;
   An outdoor heat exchanger provided outside the vehicle compartment,
   The control device radiates the refrigerant discharged from the compressor with the radiator, depressurizes the radiated refrigerant, and then absorbs heat with the heat absorber alone or with the heat absorber and the outdoor heat exchanger. The vehicle interior is dehumidified and heated, and a dehumidifying heating mode for calculating a target rotational speed of the compressor based on the pressure on the high pressure side or the temperature of the heat absorber is executed,
   The vehicle air conditioner according to any one of claims 1 to 5, wherein the compressor lower limit rotation speed restriction control is executed in the dehumidifying heating mode.

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