JP6767856B2 - Vehicle air conditioner - Google Patents

Description

The present invention relates to a heat pump type air conditioner for air-conditioning the interior of a vehicle.

Due to the emergence of environmental problems in recent years, hybrid vehicles and electric vehicles have become widespread. As an air conditioner that can be applied to such a vehicle, a compressor that compresses and discharges the refrigerant, a radiator that is provided on the vehicle interior side to dissipate the refrigerant, and a radiator that is provided on the vehicle interior side are provided. It is equipped with a heat absorber that absorbs the refrigerant and an outdoor heat exchanger that is installed outside the vehicle interior to dissipate or absorb the refrigerant. The refrigerant discharged from the compressor is dissipated in the radiator, and the refrigerant dissipated in this radiator is dissipated. A heating mode in which heat is absorbed in the outdoor heat exchanger, and dehumidification in which the refrigerant discharged from the compressor is dissipated in the radiator and the refrigerant dissipated in the radiator is absorbed only in the heat exchanger or in this heat exchanger and the outdoor heat exchanger. The heating mode, the dehumidifying / cooling mode in which the refrigerant discharged from the compressor is dissipated in the radiator and the outdoor heat exchanger and absorbed in the heat exchanger, and the dehumidifying / cooling mode in which the refrigerant discharged from the compressor is dissipated in the outdoor heat exchanger to absorb heat. A device has been developed that switches between a cooling mode in which heat is absorbed in a vessel and executes it (see, for example, Patent Document 1).

Then, in the dehumidifying / cooling mode, the cooling (dehumidifying) capacity of the heat absorber is controlled by controlling the rotation speed of the compressor based on the temperature of the heat absorber. Further, the heating capacity of the radiator is controlled by controlling the valve opening degree of the outdoor expansion valve that reduces the pressure of the refrigerant flowing into the outdoor heat exchanger based on the temperature of the radiator.

Japanese Unexamined Patent Publication No. 2014-205563

That is, in the dehumidifying / cooling mode, the temperature of the radiator can be raised by reducing the valve opening degree of the outdoor expansion valve. However, when the valve opening of the outdoor expansion valve becomes smaller, the amount of refrigerant circulating in the heat absorber decreases, so the temperature distribution of the heat absorber (the temperature varies depending on the part of the heat absorber) increases, and the dehumidification performance deteriorates. At the same time, there is a problem that it becomes difficult to establish the target blowing temperature.

The present invention has been made to solve the above-mentioned conventional technical problems, and by eliminating or suppressing the temperature distribution (temperature variation) that occurs in the heat absorber in the dehumidifying / cooling mode, the air conditioning performance in the vehicle interior is improved. It is an object of the present invention to provide an air conditioner for vehicles having an improved temperature.

The vehicle air conditioner of the present invention heats a compressor that compresses the refrigerant, an air flow passage through which the air supplied to the vehicle interior flows, and air supplied from the air flow passage to the vehicle interior by dissipating the refrigerant. A heat exchanger for absorbing heat of the refrigerant and cooling the air supplied to the passenger compartment from the air flow passage, an outdoor heat exchanger provided outside the passenger compartment for dissipating the refrigerant, and this outdoor An outdoor expansion valve for reducing the pressure of the refrigerant flowing into the heat exchanger, an indoor expansion valve for reducing the pressure of the refrigerant flowing into the heat exchanger, and a control device are provided, and the control device at least discharges the refrigerant from the compressor. A dehumidifying / cooling mode is executed in which the radiated refrigerant is radiated by a radiator and an outdoor heat exchanger, the radiated refrigerant is decompressed by an indoor expansion valve, and then heat is absorbed by a heat absorber. The control device dehumidifies. In the cooling mode, the capacity of the compressor is controlled based on the temperature of the heat exchanger, the valve opening of the outdoor expansion valve is controlled based on the temperature or pressure of the radiator, and the temperature distribution does not occur in the heat exchanger. Alternatively, the minimum valve opening degree of the outdoor expansion valve is changed so that the temperature distribution becomes smaller.

In the vehicle air conditioner according to the second aspect of the present invention, in the above invention, the control device is the minimum of the outdoor expansion valve so that the temperature distribution of the heat absorber satisfies a predetermined threshold value allowed for the temperature distribution of the heat absorber. It is characterized in that the valve opening degree is changed.

The vehicle air conditioner according to claim 3 is provided with an indoor blower for circulating air in the air flow passage in each of the above inventions, and the control device is based on the amount of ventilation to the heat absorber by the indoor blower. The feature is that the minimum valve opening degree of the outdoor expansion valve is changed in the direction of increasing the number.

In the vehicle air conditioner according to the fourth aspect of the present invention, in each of the above inventions, the control device is based on the valve opening degree of the indoor expansion valve, and the larger the valve opening degree is, the smaller the opening of the outdoor expansion valve is. It is characterized by changing the degree.

In the vehicle air conditioner according to the invention of claim 5, in each of the above inventions, the control device controls the capacity of the compressor based on the temperature of the heat absorber and the target temperature of the heat absorber in the dehumidifying / cooling mode, and also absorbs heat. The lower the target temperature of the vessel, the smaller the minimum valve opening degree of the outdoor expansion valve.

The vehicle air conditioner according to claim 6 is characterized in that, in each of the above inventions, the control device has a predetermined hysteresis when changing the minimum valve opening degree of the outdoor expansion valve.

According to the present invention, a compressor that compresses the refrigerant, an air flow passage through which the air supplied to the vehicle interior flows, and a radiator for radiating the refrigerant and heating the air supplied from the air flow passage to the vehicle interior. In addition, a heat absorber for absorbing the refrigerant and cooling the air supplied to the passenger compartment from the air flow passage, an outdoor heat exchanger provided outside the passenger compartment for dissipating the refrigerant, and this outdoor heat exchanger. An outdoor expansion valve for reducing the pressure of the inflowing refrigerant, an indoor expansion valve for reducing the pressure of the refrigerant flowing into the heat absorber, and a control device are provided, and the control device dissipates at least the refrigerant discharged from the compressor. In the vehicle air conditioner that executes the dehumidifying / cooling mode in which the heat is dissipated by the device and the outdoor heat exchanger, the radiated refrigerant is decompressed by the indoor expansion valve, and then the heat is absorbed by the heat absorber, the control device is in the dehumidifying / cooling mode. In, the capacity of the compressor is controlled based on the temperature of the heat absorber, the valve opening of the outdoor expansion valve is controlled based on the temperature or pressure of the radiator, and the temperature distribution does not occur in the heat absorber, or Since the minimum valve opening of the outdoor expansion valve is changed so that the temperature distribution becomes smaller, the valve opening of the outdoor expansion valve becomes smaller, the amount of refrigerant circulating to the heat absorber decreases, and the temperature distribution to the heat exchanger. , Or the inconvenience that the temperature distribution of the heat exchanger becomes large can be solved.

As a result, the temperature of the radiator can be expanded in a range that can be taken while maintaining the dehumidifying performance of the heat absorber in the dehumidifying / cooling mode, which can contribute to energy saving. In addition, since the target blowing temperature of the air supplied to the passenger compartment can be easily established, the air conditioning performance in the passenger compartment can be improved and the comfort of the passengers can be improved as a whole.

In this case, as in the invention of claim 2, the control device changes the minimum valve opening degree of the outdoor expansion valve so that the temperature distribution of the heat absorber satisfies a predetermined threshold value allowed for the temperature distribution of the heat absorber. By doing so, the temperature distribution of the heat absorber due to the reduction of the valve opening degree of the outdoor expansion valve can be accurately eliminated or suppressed.

Here, an indoor blower that circulates air in the air flow passage is provided, and when the indoor blower ventilates the heat absorber, the larger the amount of ventilation, the more actively the refrigerant evaporates. The temperature distribution also increases. Therefore, as in the invention of claim 3, the control device changes the minimum valve opening degree of the outdoor expansion valve in the direction of increasing the amount of ventilation based on the amount of ventilation to the heat absorber by the indoor blower. For example, the temperature distribution of the heat absorber due to the reduction of the valve opening degree of the outdoor expansion valve can be effectively eliminated or suppressed.

Further, when the valve opening degree of the indoor expansion valve for reducing the pressure of the refrigerant flowing into the heat absorber is large, the amount of refrigerant circulating in the heat absorber increases, so that the temperature distribution of the heat absorber becomes small. Therefore, as in the invention of claim 4, the control device may change the minimum valve opening degree of the outdoor expansion valve in the direction of decreasing the valve opening degree, based on the valve opening degree of the indoor expansion valve. It becomes possible to raise the temperature of the radiator without any trouble while eliminating or suppressing the temperature distribution of the heat absorber.

Furthermore, since the control device controls the compressor based on the temperature of the heat absorber and its target temperature in the dehumidifying and cooling mode, the lower the target temperature of the heat absorber, the greater the capacity of the compressor, and the amount of refrigerant circulating in the heat absorber. Will also increase. Therefore, if the control device changes the minimum valve opening degree of the outdoor expansion valve in the direction of decreasing the target temperature of the heat absorber as the target temperature of the heat absorber is lowered as in the invention of claim 5, the temperature distribution of the heat absorber can be eliminated. Alternatively, the temperature of the radiator can be raised without any trouble while suppressing the temperature.

Then, when the control device changes the minimum valve opening degree of the outdoor expansion valve as in the invention of claim 6, hunting is performed when changing the minimum valve opening degree of the outdoor expansion valve by providing a predetermined hysteresis. It becomes possible to avoid the inconvenience that occurs.

It is a block diagram of the air conditioner for a vehicle of one Embodiment to which this invention was applied. It is a block diagram of the control device of the air conditioner for a vehicle of FIG. It is a schematic diagram of the air flow passage of the air conditioner for a vehicle of FIG. It is a control block diagram concerning the compressor control in the heating mode of the heat pump controller of FIG. It is a control block diagram concerning the compressor control in the dehumidifying heating mode, the dehumidifying cooling mode, the cooling mode, and the MAX cooling mode of the heat pump controller of FIG. It is a control block diagram concerning the control of the auxiliary heater (auxiliary heating device) in the dehumidifying heating mode of the heat pump controller of FIG. It is a figure which shows the relationship between the valve opening degree of the outdoor expansion valve, and the temperature of a radiator in the dehumidifying cooling mode of the air conditioner for a vehicle of FIG. It is a figure which shows the relationship between the valve opening degree of the outdoor expansion valve, and the temperature distribution of a heat absorber in the dehumidifying cooling mode of the air conditioner for a vehicle of FIG. It is a figure which shows the relationship between the valve opening degree of an outdoor expansion valve, and the temperature distribution of a heat absorber when the ventilation amount of a heat absorber changes in the dehumidifying cooling mode of the air conditioner for a vehicle of FIG. It is a figure explaining the hysteresis at the time of changing the minimum valve opening degree of the outdoor expansion valve by the ventilation amount of a heat absorber in the dehumidifying cooling mode of the air conditioner for a vehicle of FIG. It is a figure explaining the control which changes the minimum valve opening degree of an outdoor expansion valve by the valve opening degree of an indoor expansion valve in the dehumidifying cooling mode of the air conditioner for a vehicle of FIG. It is a timing chart explaining the situation when the target temperature of the heat absorber is lowered in the dehumidifying cooling mode of the air conditioner for a vehicle of FIG. It is a figure explaining the control which changes the minimum valve opening degree of the outdoor expansion valve by the target temperature of the heat absorber in the dehumidifying cooling mode of the air conditioner for a vehicle of FIG. It is a block diagram of the air conditioner for a vehicle of another Example of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a configuration diagram of an air conditioner 1 for a vehicle according to an embodiment of the present invention. The vehicle of the 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 (neither is shown), and 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 the heating mode by the heat pump operation using the refrigerant circuit in the electric vehicle that cannot be heated by the waste heat of the engine, and further, the dehumidifying heating mode, the dehumidifying cooling mode, the cooling mode, Each operation mode of the MAX cooling mode (maximum cooling mode) and the auxiliary heater independent mode is selectively executed.

It should be noted that the present invention is effective not only for electric vehicles as vehicles but also for so-called hybrid vehicles that use an engine and an electric motor for traveling, and further, it can be applied to ordinary vehicles traveling with an engine. Needless to say.

The vehicle air conditioner 1 of the embodiment air-conditions (heating, cooling, dehumidifying, and ventilating) the interior of the electric vehicle, and includes an electric compressor 2 that compresses the refrigerant and the interior air of the vehicle. 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, dissipates this refrigerant, and supplies the refrigerant into the vehicle interior. An outdoor expansion valve 6 (decompression device) consisting of a radiator 4 for heating air and an electric valve that decompresses and expands the refrigerant during heating, and an evaporator that is provided outside the vehicle interior and functions as a radiator during cooling and during heating. An outdoor heat exchanger 7 for exchanging heat between the refrigerant and the outside air, an indoor expansion valve 8 (pressure reducing device) including an electric valve for decompressing and expanding the refrigerant, and an air flow passage 3 are provided. A heat absorber 9 for absorbing heat of the refrigerant during cooling and dehumidification to cool the air supplied from the inside and outside of the vehicle interior and an accumulator 12 and the like are sequentially connected by a refrigerant pipe 13 to form a refrigerant circuit R. Has been done.

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 forcibly ventilates the outdoor air to the outdoor heat exchanger 7 to exchange heat between the outside air and the refrigerant, whereby the outdoor air is outdoors even when the vehicle is stopped (that is, the vehicle speed is 0 km / h). The heat exchanger 7 is configured to ventilate outside air.

Further, the outdoor heat exchanger 7 has a receiver dryer portion 14 and a supercooling portion 16 in sequence on the downstream side of the refrigerant, and the refrigerant pipe 13A discharged from the outdoor heat exchanger 7 receives the receiver via an electromagnetic valve 17 that is opened during cooling. The refrigerant pipe 13B on the outlet side of the supercooling unit 16 is connected to the dryer unit 14 and is connected to the inlet side of the heat exchanger 9 via the indoor expansion valve 8. The receiver dryer section 14 and the supercooling section 16 structurally form a part of the outdoor heat exchanger 7.

Further, 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 outlet side of the heat absorber 9, and both of them constitute the internal heat exchanger 19. As a result, the refrigerant flowing into the indoor expansion valve 8 via the refrigerant pipe 13B is configured to be cooled (supercooled) by the low-temperature refrigerant leaving the heat absorber 9.

Further, the refrigerant pipe 13A coming out of the outdoor heat exchanger 7 is branched into the refrigerant pipe 13D, and the branched refrigerant pipe 13D is on the downstream side of the internal heat exchanger 19 via an electromagnetic valve 21 opened during heating. Is connected to the refrigerant pipe 13C in the above. The refrigerant pipe 13C 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.

Further, the 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) which is closed during dehumidifying heating and MAX cooling, which will be described later. There is. In this case, the refrigerant pipe 13G branches to the bypass pipe 35 on the upstream side of the solenoid valve 30, and the bypass pipe 35 also constitutes the solenoid valve 40 (which also constitutes the flow path switching device) that is opened during dehumidifying heating and MAX cooling. ) Is communicated with the refrigerant pipe 13E on the downstream side of the outdoor expansion valve 6. The bypass device 45 is composed of the bypass pipe 35, the solenoid valve 30, and the solenoid valve 40.

By configuring the bypass device 45 with such a bypass pipe 35, an electromagnetic valve 30, and an electromagnetic valve 40, a dehumidifying heating mode or MAX in which the refrigerant discharged from the compressor 2 directly flows into the outdoor heat exchanger 7 as described later. It becomes possible to smoothly switch between the cooling mode and the heating mode, the dehumidifying cooling mode, and the cooling mode in which the refrigerant discharged from the compressor 2 flows into the radiator 4.

Further, in the air flow passage 3 on the air upstream side of the heat absorber 9, each suction port of the outside air suction port and the inside air suction port is formed (represented by the suction port 25 in FIG. 1), and this suction port is formed. The suction switching damper 26 for switching the air introduced into the air flow passage 3 into the inside air (inside air circulation mode), which is the air inside the vehicle interior, and the outside air (outside air introduction mode), which is the air outside the vehicle interior, is provided. There is. Further, on the downstream side of the air of the suction switching damper 26, an indoor blower fan 27 for supplying the introduced inside air and outside air to the air flow passage 3 and ventilating the heat absorber 9 is provided.

Further, 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 inside the air flow passage 3 which is on the windward side (air upstream side) of the radiator 4 with respect to the air flow of the air flow passage 3. It is provided in. Then, when the auxiliary heater 23 is energized to generate heat, the air in the air flow passage 3 flowing into the radiator 4 via the heat absorber 9 is heated. That is, the auxiliary heater 23 serves as a so-called heater core, which heats or complements the interior of the vehicle.

Here, the air flow passage 3 on the leeward side (downstream side of the air) of the heat absorber 9 of the HVAC unit 10 is partitioned by the partition wall 10A, and the heat exchange passage 3A for heating and the bypass passage 3B bypassing the heat exchange passage 3A are formed. The above-mentioned radiator 4 and auxiliary heater 23 are arranged in the heating heat exchange passage 3A.

Further, in the air flow passage 3 on the wind side of the auxiliary heater 23, the air (inside air or outside air) in the air flow passage 3 that flows into the air flow passage 3 and passes through the heat absorber 9 is assisted. An air mix damper 28 for adjusting the ratio of ventilation to the heating heat exchange passage 3A in which the heater 23 and the radiator 4 are arranged is provided.

Further, the HVAC unit 10 on the leeward side of the radiator 4 has a FOOT (foot) outlet 29A (first outlet) and a VENT (vent) outlet 29B (a second outlet for the FOOT outlet 29A). Each outlet is formed with respect to the outlet and the DEF outlet 29C (the first outlet) and the DEF (def) outlet 29C (the second outlet). The FOOT outlet 29A is an outlet for blowing air under the feet in the vehicle interior, and is located at the lowest position. The VENT outlet 29B is an outlet for blowing air near the driver's chest and face in the vehicle interior, and is above the FOOT outlet 29A. The DEF outlet 29C is an outlet for blowing air onto the inner surface of the windshield of the vehicle, and is located at the highest position above the other outlets 29A and 29B.

The FOOT outlet 29A, the VENT outlet 29B, and the DEF outlet 29C are provided with the FOOT outlet damper 31A, the VENT outlet damper 31B, and the DEF outlet damper 31C, respectively, which control the amount of air blown out. Has been done.

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 is composed of an air conditioning controller 20 and a heat pump controller 32, each of which is composed of a microcomputer which is an example of a computer equipped with a processor, and these are CAN (Control Area Network) and LIN (Local Interconnect Network). It is connected to the vehicle communication bus 65 constituting the above. Further, 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 done.

The air conditioner controller 20 is a higher-level controller that controls the air conditioning inside the vehicle interior, and the input of the air conditioner controller 20 includes an outside air temperature sensor 33 that detects the outside air temperature Tam of the vehicle and an outside air humidity that detects the outside air humidity. The sensor 34, the HVAC suction temperature sensor 36 that detects the temperature of the air sucked into the air flow passage 3 from the suction port 25 and flows into the heat absorber 9 (suction air temperature Tas), and the temperature of the air (inside air) in the vehicle interior. An inside air temperature sensor 37 that detects (indoor temperature Tin), an inside air humidity sensor 38 that detects the humidity of the air inside the vehicle, an indoor CO ₂ concentration sensor 39 that detects the carbon dioxide concentration inside the vehicle, and a blowout into the vehicle interior. A blowout temperature sensor 41 that detects the temperature of the air to be generated, a discharge pressure sensor 42 that detects the discharge refrigerant pressure Pd of the compressor 2, and a photosensor type solar radiation sensor 51 for detecting the amount of solar radiation into the vehicle interior. Each output of the vehicle speed sensor 52 for detecting the moving speed (vehicle speed) of the vehicle is connected to the air conditioner (air conditioner) operation unit 53 for setting the set temperature and the switching of the operation mode.

Further, an outdoor blower 15, an indoor blower (blower fan) 27, a suction switching damper 26, an air mix damper 28, and outlet dampers 31A to 31C are connected to the output of the air conditioning controller 20, and they are air-conditioned. It is controlled by the controller 20.

The heat pump controller 32 is a controller that mainly controls the refrigerant circuit R, and the input of the heat pump controller 32 includes a discharge temperature sensor 43 that detects the discharge refrigerant temperature Td of the compressor 2 and a suction refrigerant of the compressor 2. A suction pressure sensor 44 that detects the pressure Ps, 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 the heat exchanger temperature sensor 46. The radiator pressure sensor 47 that detects the refrigerant pressure (radiator pressure PCI) of the radiator 4, the heat exchanger temperature sensor 48 that detects the refrigerant temperature (heat exchanger temperature Te) of the heat exchanger 9, and the refrigerant pressure of the heat exchanger 9. The heat absorber pressure sensor 49 that detects the above, the auxiliary heater temperature sensor 50 that detects the temperature of the auxiliary heater 23 (auxiliary heater temperature Tptc), and the refrigerant temperature (outdoor heat exchanger temperature TXO) at the outlet of the outdoor heat exchanger 7. Each output of the outdoor heat exchanger temperature sensor 54 to be detected and the output of the outdoor heat exchanger pressure sensor 56 to detect the refrigerant pressure (outdoor heat exchanger pressure PXO) at the outlet of the outdoor heat exchanger 7 are connected.

Further, the output of the heat pump controller 32 includes an outdoor expansion valve 6, an indoor expansion valve 8, a solenoid valve 30 (for reheating), a solenoid valve 17 (for cooling), a solenoid valve 21 (for heating), and a solenoid valve 40 (bypass). Each solenoid valve is connected and they 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 transmit and receive data to and from the heat pump controller 32 via the vehicle communication bus 65, and the heat pump controller 32 transmits and receives data. Be controlled.

The heat pump controller 32 and the air conditioning controller 20 send and receive data to and from each other via the vehicle communication bus 65, and control each device based on the output of each sensor and the settings 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 volume air volume Ga of the air flowing into the air flow passage 3 (calculated by the air conditioning controller 20), and the air volume ratio SW by the air mix damper 28 ( The output of the air conditioning operation unit 53 (calculated by the air conditioning controller 20) 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.

With the above configuration, the operation of the vehicle air conditioner 1 of the embodiment will be described next. In this embodiment, the control device 11 (air conditioning controller 20, heat pump controller 32) sets each operation mode of heating mode, dehumidifying heating mode, dehumidifying cooling mode, cooling mode, MAX cooling mode (maximum cooling mode), and auxiliary heater independent mode. Switch and execute. First, the outline of the flow and control of the refrigerant 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 by manual operation to the air conditioning operation unit 53 (manual mode), the heat pump controller 32 opens the solenoid valve 21 (for heating). Close the solenoid valve 17 (for cooling). Further, the solenoid valve 30 (for reheating) is opened, and the solenoid valve 40 (for bypass) is closed. Then, the compressor 2 is operated. The air conditioning controller 20 operates the blowers 15 and 27, and the air mix damper 28 basically heats all the air in the air flow passage 3 that has been blown out from the indoor blower 27 and passed through the heat absorber 9 for heating the heat exchange passage 3A. The auxiliary heater 23 and the radiator 4 of the above 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 solenoid valve 30. Since the air in the air flow passage 3 is ventilated through the radiator 4, the air in the air flow passage 3 is the high-temperature refrigerant in the radiator 4 (when the auxiliary heater 23 operates, the auxiliary heater 23 and the radiator 4 are used. ), On the other hand, the refrigerant in the radiator 4 is deprived of heat by air and cooled to be condensed.

The refrigerant liquefied in the radiator 4 exits the radiator 4 and then reaches the outdoor expansion valve 6 via the refrigerant pipe 13E. The refrigerant that has flowed into the outdoor expansion valve 6 is decompressed there, and then flows into the outdoor heat exchanger 7. The refrigerant that has flowed into the outdoor heat exchanger 7 evaporates and draws heat from the outside air that is ventilated by the outdoor blower 15 or by running. That is, the refrigerant circuit R serves as a heat pump. Then, the low-temperature refrigerant that has exited the outdoor heat exchanger 7 enters the accumulator 12 from the refrigerant pipe 13C via the refrigerant pipe 13A, the electromagnetic valve 21, and the refrigerant pipe 13D, and after gas-liquid separation there, the gas refrigerant is used in the compressor 2. Repeat the circulation sucked into. Since the air heated by the radiator 4 (when the auxiliary heater 23 operates, the auxiliary heater 23 and the radiator 4) is blown out from the outlets 29A to 29C, the interior of the vehicle is heated by this. 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 rotations NC of the compressor 2 is controlled based on the radiator pressure PCO and the refrigerant pressure of the radiator 4 (radiator pressure PCI. High pressure of the refrigerant circuit R) detected by the radiator pressure sensor 47, and the radiator 4 Control the heating by. 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 is controlled, and the degree of supercooling SC of the refrigerant at the outlet of the radiator 4 is controlled.

Further, in this heating mode, when the heating capacity of the radiator 4 is insufficient for the heating capacity required for the air conditioning in the vehicle interior, the heat pump controller 32 compensates for the shortage with the heat generated by the auxiliary heater 23. Controls the energization of the auxiliary heater 23. As a result, 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 arranged on the upstream side of the air of the radiator 4, the air flowing through the air flow passage 3 is ventilated to the auxiliary heater 23 in front of the radiator 4.

Here, if the auxiliary heater 23 is arranged on the downstream side of the air of the radiator 4, when the auxiliary heater 23 is configured by the PTC heater as in the embodiment, the temperature of the air flowing into the auxiliary heater 23 is the radiator. Since the temperature is increased by 4, the resistance value of the PTC heater becomes large, the current value also becomes low, and the calorific value decreases. However, by arranging the auxiliary heater 23 on the air upstream side of the radiator 4, in the embodiment, As described above, the ability of the auxiliary heater 23 composed of the PTC heater can be fully exhibited.

(2) Dehumidifying and heating mode Next, in the dehumidifying and heating mode, the heat pump controller 32 opens the solenoid valve 17 and closes the solenoid valve 21. Further, the solenoid valve 30 is closed, the solenoid 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 the blowers 15 and 27, and the air mix damper 28 basically heats all the air in the air flow passage 3 that has been blown out from the indoor blower 27 and passed through the heat absorber 9 for heating the heat exchange passage 3A. 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 to the refrigerant pipe 13G flows into the bypass pipe 35 without going to the radiator 4, passes through the solenoid valve 40, and flows into the refrigerant pipe on the downstream side of the outdoor expansion valve 6. It will reach 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 air-cooled and condensed by traveling there or by the outside air ventilated by the outdoor blower 15. The refrigerant exiting the outdoor heat exchanger 7 flows sequentially from the refrigerant pipe 13A through the solenoid valve 17 to the receiver dryer section 14 and the supercooling section 16. Here the refrigerant is supercooled.

The refrigerant exiting the supercooling section 16 of the outdoor heat exchanger 7 enters the refrigerant pipe 13B, passes through the internal heat exchanger 19, and reaches the indoor expansion valve 8. 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 is cooled by the heat absorption action at this time, and the 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 It is dehumidified. The refrigerant evaporated in the heat absorber 9 passes through the internal heat exchanger 19 and reaches the accumulator 12 via the refrigerant pipe 13C, and is repeatedly sucked into the compressor 2 through the accumulator 12.

At this time, since the valve opening degree of the outdoor expansion valve 6 is fully closed, it is possible to suppress or prevent the inconvenience that the refrigerant discharged from the compressor 2 flows back from the outdoor expansion valve 6 into the radiator 4. It becomes. As a result, it becomes possible to suppress or eliminate the decrease in the amount of refrigerant circulation and secure the air conditioning capacity. Further, in this dehumidifying / 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 and heating of the vehicle interior is performed.

The heat pump controller 32 has a target heat absorption that is a target value of the heat absorber temperature Te calculated by the air conditioner controller 20 and the temperature of the heat absorber 9 (heat absorber temperature Te) detected by the heat absorber temperature sensor 48 (target temperature of the heat absorber 9). The rotation speed NC of the compressor 2 is controlled based on the vessel temperature TEO, and the auxiliary heater temperature Tptc detected by the auxiliary heater temperature sensor 50 and the target heater temperature TCO described above (in this case, the target value of the auxiliary heater temperature Tptc) are obtained. ) By controlling the energization of the auxiliary heater 23 (heating by heat generation), while appropriately cooling and dehumidifying the air in the heat absorber 9, the auxiliary heater 23 heats the vehicle from each outlet 29A to 29C. Accurately prevent the temperature of the air blown into the room from dropping. As a result, it becomes possible to control the temperature to an appropriate heating temperature while dehumidifying the air blown into the vehicle interior, and it becomes possible to realize comfortable and efficient dehumidification heating in the vehicle interior.

Since the auxiliary heater 23 is arranged on the upstream side of the air of the radiator 4, the air heated by the auxiliary heater 23 passes through the radiator 4, but in this dehumidifying and heating mode, the refrigerant is sent to the radiator 4. Since the air is not washed away, the inconvenience that the radiator 4 absorbs heat from the air heated by the auxiliary heater 23 is also eliminated. That is, it is suppressed that the temperature of the air blown into the vehicle interior is lowered by the radiator 4, and the COP is also improved.

(3) Dehumidifying / cooling mode Next, in the dehumidifying / cooling mode, the heat pump controller 32 opens the solenoid valve 17 and closes the solenoid valve 21. Further, the solenoid valve 30 is opened and the solenoid valve 40 is closed. Then, the compressor 2 is operated. The air conditioning controller 20 operates the blowers 15 and 27, and the air mix damper 28 basically heats all the air in the air flow passage 3 that has been blown out from the indoor blower 27 and passed through the heat absorber 9 for heating the heat exchange passage 3A. 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 solenoid valve 30. Since the air in the air flow passage 3 is ventilated 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, cooled, and condensed.

The refrigerant leaving the radiator 4 reaches the outdoor expansion valve 6 via the refrigerant pipe 13E, and flows into the outdoor heat exchanger 7 via the outdoor expansion valve 6 which is slightly opened and controlled. The refrigerant flowing into the outdoor heat exchanger 7 is air-cooled and condensed by traveling there or by the outside air ventilated by the outdoor blower 15. The refrigerant exiting the outdoor heat exchanger 7 flows sequentially from the refrigerant pipe 13A through the solenoid valve 17 to the receiver dryer section 14 and the supercooling section 16. Here the refrigerant is supercooled.

The refrigerant exiting the supercooling section 16 of the outdoor heat exchanger 7 enters the refrigerant pipe 13B, passes through the internal heat exchanger 19, and reaches the indoor expansion valve 8. After the refrigerant is depressurized by the indoor expansion valve 8, it flows into the heat absorber 9 and evaporates. Due to the endothermic action at this time, the moisture in the air blown out from the indoor blower 27 condenses and adheres to the heat absorber 9, so that the air is cooled and dehumidified.

The refrigerant evaporated in the heat absorber 9 passes through the internal heat exchanger 19 and reaches the accumulator 12 via the refrigerant pipe 13C, and is repeatedly sucked into the compressor 2 through the accumulator 12. In this dehumidifying / cooling mode, since the heat pump controller 32 does not energize the auxiliary heater 23, it is cooled by the heat absorber 9, and the dehumidified air is reheated in the process of passing through the radiator 4 (the heat dissipation capacity is lower than that during heating). Will be done. As a result, the interior of the vehicle is dehumidified and cooled.

The heat pump controller 32 is transmitted from the target heat absorber temperature TEO (air conditioner controller 20) which is the temperature of the heat absorber 9 (heat absorber temperature Te) detected by the heat absorber temperature sensor 48 and its target value (target temperature of the heat absorber 9). ), The rotation speed NC of the compressor 2 (capacity of the compressor 2) is controlled. That is, when the heat absorber temperature Te is higher than the target heat absorber temperature TEO, the rotation speed NC of the compressor 2 is increased, and when the heat absorber temperature Te is lower than the target heat absorber temperature TEO, the rotation speed NC is decreased. Further, the heat pump controller 32 calculates the target radiator pressure PCO from the above-mentioned target heater temperature TCO, and the target radiator pressure PCO and the refrigerant pressure (radiator pressure PCI) of the radiator 4 detected by the radiator pressure sensor 47. The valve opening degree of the outdoor expansion valve 6 is controlled based on the high pressure of the refrigerant circuit R), and the heating by the radiator 4 is controlled.

Here, in the embodiment, the heat pump controller 32 has a valve opening degree of the outdoor expansion valve 6 based on the target radiator pressure PCO and the radiator pressure PCI calculated from the target heater temperature TCO which is the target value of the radiator temperature TCI. However, the valve opening degree of the outdoor expansion valve 6 may be controlled based on the radiator temperature TCI and the target heater temperature TCO. In any case, the heat pump controller 32 reduces the valve opening degree of the outdoor expansion valve 6 when the pressure (or temperature) of the radiator 4 is lower than the target value. When the valve opening degree of the outdoor expansion valve 6 becomes small, the supercooling degree SC of the refrigerant in the radiator 4 becomes large, so that the temperature of the radiator 4 rises and the heating capacity becomes large. On the other hand, when it is higher than the target value, the valve opening degree of the outdoor expansion valve 6 is increased to lower the temperature of the radiator 4 and the heating capacity is reduced.

(4) Cooling Mode Next, in the cooling mode, the heat pump controller 32 fully opens the valve opening degree of the outdoor expansion valve 6 in the state of the dehumidifying cooling mode. Then, the compressor 2 is operated and the auxiliary heater 23 is not energized. The air conditioning controller 20 operates the blowers 15 and 27, and in the air mix damper 28, the air in the air flow passage 3 blown out from the indoor blower 27 and passed through the heat absorber 9 is the auxiliary heater 23 of the heat exchange passage 3A for heating. And the ratio of ventilation to the radiator 4 is 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 solenoid valve 30, and the refrigerant discharged from the radiator 4 passes through the refrigerant pipe 13E and the outdoor expansion valve 6 To reach. 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 air-cooled by running or by the outside air ventilated by the outdoor blower 15 and condensed. Liquefaction. The refrigerant exiting the outdoor heat exchanger 7 flows sequentially from the refrigerant pipe 13A through the solenoid valve 17 to the receiver dryer section 14 and the supercooling section 16. Here the refrigerant is supercooled.

The refrigerant exiting the supercooling section 16 of the outdoor heat exchanger 7 enters the refrigerant pipe 13B, passes through the internal heat exchanger 19, and reaches the indoor expansion valve 8. 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 is cooled by the endothermic action at this time. Further, the moisture in the air condenses and adheres to the heat absorber 9.

The refrigerant evaporated in the heat absorber 9 passes through the internal heat exchanger 19 and reaches the accumulator 12 via the refrigerant pipe 13C, and is repeatedly sucked into the compressor 2 through the accumulator 12. The dehumidified air cooled by the heat absorber 9 is blown out into the vehicle interior from the outlets 29A to 29C (a part of the air passes through the radiator 4 to exchange heat), which cools the vehicle interior. It will be done. Further, in this cooling mode, the heat pump controller 32 uses 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 above-mentioned target heat absorber temperature TEO which is the target value thereof. Controls the number of rotations NC.

(5) MAX cooling mode (maximum cooling mode)
Next, in the MAX cooling mode as the maximum cooling mode, the heat pump controller 32 opens the solenoid valve 17 and closes the solenoid valve 21. Further, the solenoid valve 30 is closed, the solenoid 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 the blowers 15 and 27, and in the air mix damper 28, the air in the air flow passage 3 blown out from the indoor blower 27 and passed through the heat absorber 9 is an auxiliary heater of the heat exchange passage 3A for heating. The ratio of ventilation to 23 and the radiator 4 is adjusted.

As a result, 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 solenoid valve 40, and flows into the refrigerant pipe on the downstream side of the outdoor expansion valve 6. It will reach 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 air-cooled and condensed by traveling there or by the outside air ventilated by the outdoor blower 15. The refrigerant exiting the outdoor heat exchanger 7 flows sequentially from the refrigerant pipe 13A through the solenoid valve 17 to the receiver dryer section 14 and the supercooling section 16. Here the refrigerant is supercooled.

The refrigerant exiting the supercooling section 16 of the outdoor heat exchanger 7 enters the refrigerant pipe 13B, passes through the internal heat exchanger 19, and reaches the indoor expansion valve 8. 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 is cooled by the endothermic action at this time. Further, since the 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 passes through the internal heat exchanger 19 and reaches the accumulator 12 via the refrigerant pipe 13C, and is repeatedly sucked into the compressor 2 through the accumulator 12. At this time, since the outdoor expansion valve 6 is fully closed, it is possible to suppress or prevent the inconvenience that the refrigerant discharged from the compressor 2 flows back from the outdoor expansion valve 6 into the radiator 4. .. As a result, it becomes possible to suppress or eliminate the decrease in the amount of refrigerant circulation and secure the air conditioning capacity.

Here, since the high-temperature refrigerant flows through the radiator 4 in the above-mentioned cooling mode, direct heat conduction from the radiator 4 to the HVAC unit 10 occurs to some extent, but in this MAX cooling mode, the refrigerant flows through the radiator 4. Does not flow, so that the heat transferred from the radiator 4 to the HVAC unit 10 does not heat the air in the air flow passage 3 from the heat absorber 9. Therefore, the vehicle interior is strongly cooled, and particularly in an environment where the outside air temperature Tam is high, the vehicle interior can be quickly cooled and comfortable vehicle interior air conditioning can be realized. Further, even in this MAX cooling mode, 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 the above-mentioned target heat absorber temperature TEO which is the target value thereof. The number of rotations NC of 2 is controlled.

(6) Auxiliary heater independent mode The control device 11 of the embodiment stops the compressor 2 and the outdoor blower 15 of the refrigerant circuit R when over-frost occurs in the outdoor heat exchanger 7, and the auxiliary heater 23 Has an auxiliary heater independent mode in which the vehicle interior is heated only by the auxiliary heater 23. Also in this case, the heat pump controller 32 controls the 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.

Further, the air conditioning controller 20 operates the indoor blower 27, and the air mix damper 28 ventilates the air in the air flow passage 3 blown from the indoor blower 27 to the auxiliary heater 23 of the heating heat exchange passage 3A to increase the air volume. It is in a state to be adjusted. Since the air heated by the auxiliary heater 23 is blown out into the vehicle interior from the outlets 29A to 29C, the interior of the vehicle is heated by this.

(7) Switching of operation mode The air conditioning controller 20 calculates the target blowout 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 vehicle interior.
TAO = (Tset-Tin) x K + Tbal (f (Tset, SUN, Tam))
・ ・ (I)
Here, Tset is the set temperature in the vehicle interior set by the air conditioning operation unit 53, Tin is the indoor temperature detected by the inside air temperature sensor 37, K is a coefficient, Tbal is the set temperature Tset, and the amount of solar radiation detected by the solar radiation sensor 51. It is a balance value calculated from the outside air temperature Tam detected by the SUN and the outside air temperature sensor 33. In general, the target outlet temperature TAO increases as the outside air temperature Tam decreases, and decreases as the outside air temperature Tam increases.

The heat pump controller 32 is any 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 at the time of activation and the target blowout 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. After startup, the outside air temperature Tam, the humidity inside the vehicle, the target blowout temperature TAO, the heating temperature TH (the temperature of the air on the leeward side of the radiator 4; estimated value), the target heater temperature TCO, the heater temperature Te, By switching each operation mode based on parameters such as the target heat absorber temperature TEO and the presence or absence of dehumidification request in the vehicle interior, the heating mode, dehumidification heating mode, and dehumidification can be performed accurately according to the environmental conditions and the necessity of dehumidification. By switching between the cooling mode, the cooling mode, the MAX cooling mode, and the auxiliary heater independent mode, the temperature of the air blown into the vehicle interior is controlled to the target outlet temperature TAO, and comfortable and efficient vehicle interior air conditioning is realized.

(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 rotation speed (compressor target rotation speed) TGNCh of the compressor 2 for the heating mode. The F / F (feed forward) operation amount calculation unit 58 of the heat pump controller 32 has the outside air temperature Tam obtained from the outside air temperature sensor 33, the blower voltage BLV of the indoor blower 27, and SW = (TAO-Te) / (TH-Te). ), The air volume ratio SW by the air mix damper 28, the target supercooling degree TGSC which is the target value of the supercooling degree SC at the outlet of the radiator 4, and the above-mentioned target heater which is the target value of the temperature of the radiator 4 The F / F operation amount TGNChff of the compressor target rotation speed is calculated based on the temperature TCO (transmitted from the air conditioning controller 20) and the target radiator pressure PCO which is the target value of the pressure of the radiator 4.

Here, the TH for calculating the air volume ratio SW is the temperature of the air on the leeward side of the radiator 4 (hereinafter referred to as the heating temperature), and the heat pump controller 32 uses the equation (II) for the primary delay calculation shown below. presume.
TH = (INTL x TH0 + Tau x THz) / (Tau + INTL) ... (II)
Here, INTL is the calculation period (constant), Tau is the time constant of the first-order delay, TH0 is the steady-state value of the heating temperature TH in the steady state before the first-order delay calculation, and THH is the previous value of the heating temperature TH. By estimating the heating temperature TH in this way, it is not necessary to provide a special temperature sensor.

By changing the time constant Tau and the steady-state value TH0 according to the operation mode described above, the heat pump controller 32 makes the estimation formula (II) described above different depending on the operation mode, and estimates the heating temperature TH. Then, this 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 calculation unit 59 based on the target supercooling degree TGSC and the target heater temperature TCO. Further, the F / B (feedback) operation amount calculation unit 60 calculates the F / B operation amount TGNChfb of the compressor target rotation speed based on the target radiator pressure PCO and the radiator pressure PCI which is the refrigerant pressure of the radiator 4. To do. Then, the F / F operation amount TGNCnff calculated by the F / F operation amount calculation unit 58 and the TGNChfb calculated by the F / B operation amount calculation unit 60 are added by the adder 61, and are controlled by the limit setting unit 62 as the control upper limit value. After the lower limit is set, it is determined as the compressor target rotation speed TGNCh. In the heating mode, the heat pump controller 32 controls the rotation speed NC of the compressor 2 based on the compressor target rotation speed TGNCh.

(9) Control of the compressor 2 in the dehumidifying / heating mode, the dehumidifying / cooling mode, the cooling mode, and the MAX cooling mode by the heat pump controller 32 On the other hand, FIG. It is a control block diagram of the heat pump controller 32 which determines the target rotation speed (compressor target rotation speed) TGNCc of the compressor 2. The F / F operation amount calculation unit 63 of the heat pump controller 32 has an outside air temperature Tam, a volume air volume Ga of the air flowing into the air flow passage 3, and a target heat dissipation which is a target value of the pressure of the radiator 4 (radiator pressure PCI). The F / F manipulated variable TGNCcff of the compressor target rotation speed is calculated based on the instrument pressure PCO and the target heater temperature TEO which is the target value of the temperature of the heat absorber 9 (heat absorber temperature Te).

Further, the F / B operation amount calculation unit 64 calculates the F / B operation amount TGNCcfb of the compressor target rotation 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 operation amount TGNCcff calculated by the F / F operation amount calculation unit 63 and the F / B operation amount TGNCcffb calculated by the F / B operation amount calculation unit 64 are added by the adder 66, and are added by the limit setting unit 67. After the limit of the control upper limit value and the control lower limit value is set, it is determined as the compressor target rotation speed TGNCc. In the dehumidifying / heating mode, the heat pump controller 32 controls the rotation speed NC of the compressor 2 based on the compressor target rotation speed TGNCc.

(10) Control of Auxiliary Heater 23 in Dehumidifying and Heating Mode by Heat Pump Controller 32 Next, 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 and heating mode. The target heater temperature TCO and the auxiliary heater temperature Tptc are input to the subtractor 73 of the heat pump controller 32, and the deviation (TCO-Tptc) between the target heater temperature TCO and the auxiliary heater temperature Tptc is calculated. This deviation (TCO-Tptc) is input to the F / B control unit 74, and the F / B control unit 74 eliminates the deviation (TCO-Tptc) so that the auxiliary heater temperature Tptc becomes the target heater temperature TCO. Calculate the required capacity F / B operation amount.

The auxiliary heater requesting capacity F / B operation amount calculated by the F / B control unit 74 is determined as the auxiliary heater requesting capacity TGQPTC after the limit setting unit 76 limits the control upper limit value and the control lower limit value. .. In the dehumidifying / heating mode, the controller 32 controls the energization of the auxiliary heater 23 based on the auxiliary heater required capacity TGQPTC, so that the auxiliary heater temperature Tptc becomes the target heater temperature TCO and the auxiliary heater 23 generates heat (heating). To control.

In this way, 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 in the dehumidifying heating mode, and also controls the heat generation of the auxiliary heater 23 based on the target heater temperature TCO. As a result, the cooling and dehumidification by the heat absorber 9 and the heating by the auxiliary heater 23 in the dehumidification and heating mode are accurately controlled. As a result, it is possible to control the temperature to a more accurate heating temperature while dehumidifying the air blown into the vehicle interior more appropriately, and to realize more comfortable and efficient dehumidification and heating of the vehicle interior. Will be able to.

(11) Control of Air Mix Damper 28 Next, 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 air volume of the air flowing into the air flow passage 3 described above, Te is the temperature of the heat absorber, 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 has an air volume of that ratio based on the air volume ratio SW that ventilates the radiator 4 and the auxiliary heater 23 of the heat exchange passage 3A for heating calculated by the above-mentioned formula (the following formula (III)). 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 volume ratio SW that ventilates the radiator 4 and the auxiliary heater 23 of the heat exchange passage 3A for heating changes in the range of 0 ≦ SW ≦ 1, and “0” does not allow ventilation to 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 ventilated to the bypass passage 3B, and the air mix fully open state in which all the air in the air flow passage 3 is ventilated to the heating heat exchange passage 3A in "1". It becomes. That is, the air volume to the radiator 4 is Ga × SW.

(12) Control of changing the minimum valve opening degree of the outdoor expansion valve 6 in the dehumidifying / cooling mode by the heat pump controller 32 (No. 1)
Next, an example of control for changing the minimum valve opening degree ECCVpcmin of the outdoor expansion valve 6 in the dehumidifying / cooling mode by the heat pump controller 32 will be described with reference to FIGS. 7 to 10. As described above, the heat pump controller 32 controls the valve opening ECCVpc of the outdoor expansion valve 6 based on the target radiator pressure PCO and the radiator pressure PCI in the dehumidifying / cooling mode in the embodiment. In this case, the heat pump controller 32 controls the valve opening ECCVpc of the outdoor expansion valve 6. Reference numeral 32 denotes a valve opening degree ECCVpc of the outdoor expansion valve 6 is controlled between a predetermined maximum valve opening degree ECCVpcmax and a minimum valve opening degree ECCVpcmin.

If the valve opening ECCVpc of the outdoor expansion valve 6 is reduced (the outdoor expansion valve 6 is throttled), the temperature of the radiator 4 (radiator temperature TCI) increases and the heating capacity also increases as shown in FIG. .. However, when the valve opening degree ECCVpc of the outdoor expansion valve 6 becomes smaller, the amount of refrigerant circulating in the heat absorber 9 decreases by that amount, so that the refrigerant completely evaporates at an early stage when it flows into the heat absorber 9. Therefore, the temperature of the heat absorber 9 is low and high, and the temperature distribution is generated (temperature variation). As shown in FIG. 8, the smaller the valve opening ECCVpc of the outdoor expansion valve 6, the lower the temperature. The distribution becomes large.

When the temperature distribution occurs in the heat absorber 9, the dehumidifying performance deteriorates, and it becomes difficult to cool the ventilated air in some parts, making it difficult to establish the target blowout temperature TAO, and the air conditioning performance in the vehicle interior. Will get worse.

On the other hand, there is a correlation between the amount of ventilation to the heat absorber 9 by the indoor blower 27 and the temperature distribution, and the larger the amount of ventilation, the easier it is for the temperature distribution to occur (note that all the air blown from the indoor blower 27 is the heat absorber. Since the air is ventilated to 9, the above-mentioned volume air volume Ga becomes the air volume to the heat absorber 9). This situation is shown in FIG. In the embodiment, for example, the amount of ventilation to the heat absorber 9 is divided into three stages. In FIG. 9, L1 is the temperature distribution of the heat absorber 9 when the ventilation amount is high, and L2 is the temperature distribution when the ventilation amount is medium. L3 shows the temperature distribution when the air volume is low. For example, assuming that the valve opening degree ECCVpc of the outdoor expansion valve 6 is B (FIG. 9), the larger the amount of ventilation to the heat absorber 9, the more actively the refrigerant in the heat absorber 9 evaporates. The temperature distribution of the heat absorber 9 also increases, and the difference between the temperature distribution L1 when the air volume is high and the temperature distribution L2 when the air volume is medium is X1 (FIG. 9).

Therefore, in the embodiment, a predetermined threshold value X2 allowed for the temperature distribution of the heat absorber 9 is set. In the embodiment, this threshold value X2 is a temperature distribution when the difference between the temperature of the air blown to the driver's seat side in the vehicle interior and the temperature of the air blown to the passenger's seat side is a predetermined value (for example, 5 deg). , This shall be obtained by experiment in advance. Not limited to this, for example, the temperature of a plurality of locations of the heat absorber 9 may be measured in advance, and the threshold value X2 may be set directly from the difference between them.

As shown in FIG. 9, when the ventilation volume of the heat absorber 9 is high, the temperature distribution L1 of the heat absorber 9 increases to the threshold value X2. The valve opening degree of the outdoor expansion valve 6 is A, and the ventilation volume of the heat absorber 9 is medium. The temperature distribution L2 of the heat absorber 9 increases to the threshold X2 when the air volume is high. The valve opening of the outdoor expansion valve 6 is B, and the temperature distribution L3 of the heat absorber 9 is the threshold X2 when the ventilation volume of the heat absorber 9 is low. Assuming that the valve opening degree of the outdoor expansion valve 6 is increased to C, the heat pump controller 32 uses the outdoor expansion valve 6 in which the temperature distribution L1 of the heat absorber 9 becomes the threshold value X2 when the ventilation amount of the heat absorber 9 is high. The valve opening A (FIG. 9) is set to the minimum valve opening ECCVpcmin of the outdoor expansion valve 6, and when the ventilation volume of the heat absorber 9 is medium air volume, the temperature distribution L2 of the heat absorber 9 becomes the threshold value X2. The valve opening degree B (FIG. 9) of the outdoor expansion valve 6 is set to the minimum valve opening degree ECCVpcmin of the outdoor expansion valve 6, and when the ventilation volume of the heat absorber 9 is low, the temperature distribution L3 of the heat absorber 9 becomes the threshold value X2. The minimum valve opening degree ECCVpcmin of the outdoor expansion valve 6 is changed so that the valve opening degree C (FIG. 9) of No. 6 is set to the minimum valve opening degree ECCVpcmin of the outdoor expansion valve 6. As is clear from FIG. 9, the relationship of each valve opening degree (minimum valve opening degree ECCVpcmin) is A> B> C. Further, although the ventilation amount is determined in three stages in the embodiment, it may be determined in two stages, and conversely, it may be determined in more stages (four or more stages).

As a result, the valve opening degree of the outdoor expansion valve 6 is not reduced to a value at which the temperature distribution of the heat absorber 9 becomes larger than the threshold value X2 at any ventilation amount. That is, the heat pump controller 32 minimizes the outdoor expansion valve 6 so that the temperature distribution of the heat absorber 9 satisfies the threshold value X2 (the temperature distribution is equal to or less than the threshold value X2) based on the ventilation amount (volume air volume Ga) of the heat absorber 9. The valve opening ECCVpcmin will be changed. However, when the heat pump controller 32 changes the minimum valve opening degree ECCVpcmin of the outdoor expansion valve 6 according to the ventilation amount of the heat absorber 9, the heat pump controller 32 gives a predetermined hysteresis to the ventilation amount as shown in FIG. Although the arrow line indicating the changing direction is shown diagonally in FIG. 10, it actually changes in the vertical direction.

As described above, in the heat pump controller 32, the minimum valve opening degree of the outdoor expansion valve 6 is increased in the direction of increasing the ventilation amount (high air volume) and decreasing in the smaller amount (low air volume) according to the ventilation amount of the heat absorber 9. Since the ECCVpcmin is changed, the temperature distribution does not occur in the heat absorber 9, or the temperature distribution becomes smaller. As a result, the valve opening ECCVpc of the outdoor expansion valve 6 becomes smaller, the amount of refrigerant circulating to the heat absorber 9 decreases, a temperature distribution occurs in the heat absorber 9, or the temperature distribution of the heat absorber 9 becomes larger. It will be possible to eliminate it. Then, while maintaining the dehumidifying performance of the heat absorber 9 in the dehumidifying / cooling mode, the temperature of the radiator 4 (radiator temperature TCI) can also be expanded in a range that can be taken, which can contribute to energy saving. It will be possible. Further, since the target blowing temperature TAO of the air supplied to the vehicle interior can be easily established, the air conditioning performance in the vehicle interior can be improved and the comfort of the passenger can be improved as a whole.

In this case, in the embodiment, the heat pump controller 32 changes the minimum valve opening ECCVpcmin of the outdoor expansion valve 6 so that the temperature distribution of the heat absorber 9 satisfies a predetermined threshold value X2 allowed for the temperature distribution of the heat absorber 9. Therefore, the temperature distribution of the heat absorber 9 due to the reduction of the valve opening degree ECCVpc of the outdoor expansion valve 6 can be accurately eliminated or suppressed.

Further, in this embodiment, the heat pump controller 32 changes the minimum valve opening degree ECCVpcmin of the outdoor expansion valve 6 in the direction of increasing the amount of ventilation to the heat absorber 9 by the indoor blower 6. Therefore, the temperature distribution of the heat absorber 9 due to the reduction of the valve opening degree ECCVpc of the outdoor expansion valve 6 can be effectively eliminated or suppressed.

Further, in the embodiment, since the heat pump controller 32 has a predetermined hysteresis when changing the minimum valve opening degree ECCVpcmin of the outdoor expansion valve 6, the minimum valve opening degree ECCVpc of the outdoor expansion valve 6 is changed. At that time, the inconvenience of hunting can be avoided in advance.

(13) Control of changing the minimum valve opening degree of the outdoor expansion valve 6 in the dehumidifying / cooling mode by the heat pump controller 32 (Part 2)
Further, when the valve opening TXV of the indoor expansion valve 8 for reducing the pressure of the refrigerant flowing into the heat absorber 9 is large, the amount of refrigerant circulating in the heat absorber 9 increases, so that the temperature distribution of the heat absorber 9 becomes small. Therefore, the heat pump controller 32 changes the minimum valve opening degree ECCVpcmin of the outdoor expansion valve 6 in place of or in addition to the above embodiment (No. 1) or based on the valve opening degree TXV of the indoor expansion valve 8.

FIG. 11 is a diagram illustrating an example of control for changing the minimum valve opening degree ECCVpcmin of the outdoor expansion valve 6 by the valve opening degree TXV of the indoor expansion valve 8 in addition to the above embodiment (No. 1). In this embodiment, the ventilation to the heat absorber 9 described above depends on whether the valve opening TXV of the indoor expansion valve 8 is on the open side (large valve opening), the reference, or the closed side (small valve opening). The valve openings A, B, and C, which are the minimum valve opening ECCVpcmin based on the volume (high air volume, medium air volume, low air volume), are further changed.

That is, when the valve opening TXV of the indoor expansion valve 8 is on the opening side (the valve opening is large) and the amount of ventilation to the heat absorber 9 is high, the minimum valve of the outdoor expansion valve 6 is The opening degree ECCVpcmin is A-α smaller than the valve opening degree A described above, B-β smaller than the valve opening degree B described above when the air volume is medium, and the valve described above when the air volume is low. Let C-γ be smaller than the opening degree C (however, α, β, and γ are positive numbers).

When the valve opening TXV of the indoor expansion valve 8 is a reference value, the minimum valve opening ECCVpcmin of the outdoor expansion valve 6 is set by the valve opening A set from the amount of ventilation to the heat absorber 9 described above. , B, C.

On the other hand, when the valve opening TXV of the indoor expansion valve 8 is on the closing side (the valve opening is small) and the amount of ventilation to the heat absorber 9 is high, the minimum valve of the outdoor expansion valve 6 is The opening degree ECCVpcmin is set to A + δ, which is larger than the valve opening degree A described above, B + ε is set to be larger than the valve opening degree B described above when the air volume is medium, and when the air volume is low, the valve opening degree C is larger than the valve opening degree C described above. Is also large C + ζ (however, δ, ε, and ζ are positive numbers).

In this way, the heat pump controller 32 changes the minimum valve opening ECCVpcmin of the outdoor expansion valve 6 in the direction of decreasing the valve opening TXV based on the valve opening TXV of the indoor expansion valve 8. It becomes possible to raise the temperature of the radiator 4 without any trouble while eliminating or suppressing the temperature distribution of the heat absorber 9.

Regardless of this embodiment, the minimum valve opening ECCVpcmin of the outdoor expansion valve 6 is changed based only on the valve opening TXV of the indoor expansion valve 8 without making the change based on the amount of ventilation to the heat absorber 9. You may try to do it. In that case, for example, based only on the valve opening B described above, when the valve opening TXV of the indoor expansion valve 8 is on the opening side, the minimum valve opening ECCVpcmin of the outdoor expansion valve 6 is set to B-β, and the valve opening is set. B is set when TXV is the reference, B + ε is set when the valve opening TXV is on the closing side, and so on.

(14) Control of changing the minimum valve opening degree of the outdoor expansion valve 6 in the dehumidifying / cooling mode by the heat pump controller 32 (No. 3)
Further, as described above, in the dehumidifying / cooling mode, the heat pump controller 32 controls the rotation speed NC of the compressor 2 based on the temperature of the heat absorber 9 (heat absorber temperature Te) and the target heat absorber temperature TEO which is the target temperature thereof. As shown in FIG. 12, when the target heat absorber temperature TEO (target temperature of the heat absorber 9) becomes low, the rotation speed NC of the compressor 2 becomes high, its capacity is increased, and the refrigerant circulation amount of the heat absorber 9 is also increased. More. As a result, the temperature distribution of the heat absorber 9 becomes smaller (the portion indicated by X3 in FIG. 12), and the temperature of the radiator 4 (radiator temperature TCI) also rises.

Therefore, even if the minimum valve opening ECCVpcmin of the outdoor expansion valve 6 is lowered (the portion shown by X4 in FIG. 12, the radiator temperature TCI also rises), the temperature distribution of the heat absorber 9 is before the target heat absorber temperature TEO drops. It grows only to the state (the part indicated by X5 in FIG. 12).

Therefore, the heat pump controller 32 changes the minimum valve opening degree ECCVpcmin of the outdoor expansion valve 6 in place of or in addition to the above embodiments (No. 1) and (No. 2) based on the target heat absorber temperature TEO. ..

FIG. 13 is a diagram illustrating an example of control for changing the minimum valve opening degree ECCVpcmin of the outdoor expansion valve 6 depending on the target heat absorber temperature TEO in addition to the above embodiment (No. 1). In this embodiment, the minimum valve opening ECCVpcmin based on the above-mentioned air flow rate (high air volume, medium air volume, low air volume) to the heat absorber 9 according to whether the target heat absorber temperature TEO is low, medium, or high. The valve openings A, B, and C are further changed. Although FIG. 13 shows only the valve opening A when the air volume is high, the valve opening B when the air volume is medium and the valve opening C when the air volume is low are also changed in the same manner.

That is, when the target heat absorber temperature TEO is low and the amount of ventilation to the heat absorber 9 is high, the minimum valve opening ECCVpcmin of the outdoor expansion valve 6 is set to A-η, which is smaller than the valve opening A described above. And. When the target heat absorber temperature TEO is medium, the minimum valve opening degree ECCVpcmin of the outdoor expansion valve 6 is set to the valve opening degree A set from the high air volume to the heat absorber 9 described above. Further, when the target heat absorber temperature TEO is high and the amount of ventilation to the heat absorber 9 is high, the minimum valve opening ECCVpcmin of the outdoor expansion valve 6 is set to A + θ, which is larger than the valve opening A described above. (However, η and θ are positive numbers).

In this way, the heat pump controller 32 changes the minimum valve opening degree ECCVpcmin of the outdoor expansion valve 6 in the direction of decreasing the target temperature (target heat absorber temperature TEO) of the heat absorber 9, so that the temperature of the heat absorber 9 is increased. It becomes possible to raise the temperature of the radiator 4 (radiator temperature TCI) without any trouble while eliminating or suppressing the distribution (FIG. 12).

In the case of this embodiment as well, regardless of the above, the minimum valve opening degree ECCVpcmin of the outdoor expansion valve 6 is set based only on the target heat absorber temperature TEO without making a change based on the amount of ventilation to the heat absorber 9. You may change it. In that case, for example, as shown in FIG. 13, based only on the valve opening A described above, when the target heat absorber temperature TEO is low, the minimum valve opening ECCVpcmin of the outdoor expansion valve 6 is set to A-η, and when it is medium. Is A, and when it is high, it is A + θ.

Next, FIG. 14 shows a block diagram of the vehicle air conditioner 1 of another embodiment to which the present invention is applied. In this figure, those shown by the same reference numerals as those in FIG. 1 have the same or similar functions. In the case of this embodiment, the outlet of the supercooling unit 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.

Further, the refrigerant pipe 13E on the outlet side of the radiator 4 is branched in front of the outdoor expansion valve 6, and the branched refrigerant pipe (hereinafter referred to as the second bypass pipe) 13F is the solenoid valve 22 (for dehumidification). It is communicated with the refrigerant pipe 13B on the downstream side of the check valve 18 via the check valve 18. Further, an evaporation pressure adjusting valve 70 is connected to the refrigerant pipe 13C on the outlet side of the heat absorber 9 on the downstream side of the refrigerant of the internal heat exchanger 19 and on the upstream side of the refrigerant from the confluence with the refrigerant pipe 13D. ..

The solenoid valve 22 and the evaporation pressure adjusting valve 70 are also connected to the output of the heat pump controller 32. The bypass device 45 including the bypass pipe 35, the solenoid valve 30, and the solenoid valve 40 in FIG. 1 of the above-described embodiment is not provided. Others are the same as in FIG. 1, and the description thereof will be omitted.

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 and executes each operation mode of the heating mode, the dehumidifying heating mode, the internal cycle mode, the dehumidifying cooling mode, the cooling mode, and the auxiliary heater independent mode (MAX cooling mode exists in this embodiment). do not do). Since the operation and the flow of the refrigerant when the heating mode, the dehumidifying cooling mode, and the cooling mode are selected, and the auxiliary heater independent mode are the same as those in the above-described embodiment (Example 1), the description thereof will be 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.

(15) Dehumidifying and heating mode of the vehicle air conditioner 1 of FIG. 14 On the other hand, when the dehumidifying and heating mode is selected, in this embodiment, the heat pump controller 32 opens the solenoid valve 21 (for heating) and the solenoid valve 17 (for heating). Close (for cooling). In addition, the solenoid valve 22 (for dehumidification) is opened. Then, the compressor 2 is operated. The air conditioning controller 20 operates the blowers 15 and 27, and the air mix damper 28 basically heats all the air in the air flow passage 3 that has been blown out from the indoor blower 27 and passed through the heat absorber 9 for heating the heat exchange passage 3A. 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. Since the air in the air flow passage 3 flowing into the heating heat exchange passage 3A is ventilated 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 radiator The refrigerant in 4 is deprived of heat by air, cooled, and condensed.

The refrigerant liquefied in the radiator 4 exits the radiator 4 and then reaches the outdoor expansion valve 6 via the refrigerant pipe 13E. The refrigerant that has flowed into the outdoor expansion valve 6 is decompressed there, and then flows into the outdoor heat exchanger 7. The refrigerant that has flowed into the outdoor heat exchanger 7 evaporates and draws heat from the outside air that is ventilated by the outdoor blower 15 or by running. That is, the refrigerant circuit R serves as a heat pump. Then, the low-temperature refrigerant that has exited the outdoor heat exchanger 7 enters the accumulator 12 from the refrigerant pipe 13C via the refrigerant pipe 13A, the electromagnetic valve 21, and the refrigerant pipe 13D, and after gas-liquid separation there, the gas refrigerant is used in the compressor 2. Repeat the circulation sucked into.

Further, a part of the condensed refrigerant flowing through the refrigerant pipe 13E via the radiator 4 is diverted, and reaches the indoor expansion valve 8 from the second bypass pipe 13F and the refrigerant pipe 13B via the solenoid valve 22 via the internal heat exchanger 19. Will be. After the refrigerant is depressurized by the indoor expansion valve 8, it flows into the heat absorber 9 and evaporates. Due to the endothermic action at this time, the moisture in the air blown out from the indoor blower 27 condenses and adheres to the heat absorber 9, so that the air is cooled and dehumidified.

The refrigerant evaporated in the heat absorber 9 joins the refrigerant from the refrigerant pipe 13D in the refrigerant pipe 13C through the internal heat exchanger 19 and the evaporation pressure adjusting valve 70 in that order, and then is sucked into the compressor 2 through the accumulator 12. repeat. The air dehumidified by the heat absorber 9 is reheated in the process of passing through the radiator 4, so that the dehumidifying and heating of the vehicle interior is performed.

The air conditioning controller 20 transmits the target heater temperature TCO (target value of radiator outlet temperature TCI) calculated from the target outlet temperature TAO to the heat pump controller 32. The heat pump controller 32 calculates the target radiator pressure PCO (target value of the radiator pressure PCI) from the target heater temperature TCO, and the target radiator pressure PCO and the refrigerant of the radiator 4 detected by the radiator pressure sensor 47. The rotation speed NC of the compressor 2 is controlled based on the pressure (radiator pressure PCI; high pressure of the refrigerant circuit R), and the heating by the radiator 4 is controlled. Further, the heat pump controller 32 controls 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. Further, the heat pump controller 32 opens (expands the flow path) / closes (a small amount of refrigerant flows) the evaporation pressure adjusting valve 70 based on the temperature Te of the heat absorber 9 detected by the heat absorber temperature sensor 48, and the heat absorber 9 Prevents the inconvenience of freezing due to the temperature of the

(16) Internal Cycle Mode of Vehicle Air Conditioning Device 1 of FIG. 14 In the internal cycle mode, the heat pump controller 32 fully closes the outdoor expansion valve 6 (fully closed position) in the dehumidifying and heating mode. The solenoid valve 21 is closed. By closing the outdoor expansion valve 6 and the solenoid valve 21, the inflow of the refrigerant into the outdoor heat exchanger 7 and the outflow of the refrigerant from the outdoor heat exchanger 7 are prevented, so that the radiator 4 All of the condensed refrigerant flowing through the refrigerant pipe 13E flows through the solenoid valve 22 to the second bypass pipe 13F. Then, the refrigerant flowing through the second bypass pipe 13F reaches the indoor expansion valve 8 from the refrigerant pipe 13B via 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. Due to the endothermic action at this time, the moisture in the air blown out from the indoor blower 27 condenses and adheres to the heat absorber 9, so that the air is cooled and dehumidified.

The refrigerant evaporated by the heat absorber 9 flows through the refrigerant pipe 13C in sequence through the internal heat exchanger 19 and the evaporation pressure adjusting valve 70, and repeats the circulation of being 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 and heating the interior of the vehicle is performed by this, but in this internal cycle mode, the air flow on the indoor side. Since the refrigerant is circulated between the radiator 4 (heat dissipation) and the heat absorber 9 (heat absorption) in the path 3, the heat from the outside air is not pumped up, and the heating for the power consumed by the compressor 2 is not performed. The ability is demonstrated. Since the entire amount of the refrigerant flows through the heat absorber 9 that exerts a dehumidifying action, the dehumidifying capacity is high but the heating capacity is low as compared with the dehumidifying and heating mode.

The air conditioning controller 20 transmits the target heater temperature TCO (target value of radiator outlet temperature TCI) calculated from the target outlet temperature TAO to the heat pump controller 32. The heat pump controller 32 calculates the target radiator pressure PCO (target value of the radiator pressure PCI) from the transmitted target heater temperature TCO, and the target radiator pressure PCO and the radiator 4 detected by the radiator pressure sensor 47. The rotation speed NC of the compressor 2 is controlled based on the refrigerant pressure (radiator pressure PCI; high pressure of the refrigerant circuit R), and the heating by the radiator 4 is controlled.

Since the flow and control of the refrigerant in the dehumidifying / cooling mode of the vehicle air conditioner 1 of the second embodiment are the same as those in the above-described first embodiment, the heat pump controller 32 is also used in the dehumidifying / cooling mode in this embodiment. By controlling the change of the minimum valve opening degree of the outdoor expansion valve 6 (No. 1) to (No. 3) described above (12) to (14), the temperature distribution does not occur in the heat absorber 9 as described above, or , The temperature distribution becomes smaller. As a result, the valve opening ECCVpc of the outdoor expansion valve 6 is similarly reduced, the amount of refrigerant circulating to the heat absorber 9 is reduced, a temperature distribution is generated in the heat absorber 9, or the temperature distribution of the heat absorber 9 is increased. You will be able to eliminate the inconvenience.

Similarly, in this case as well, the temperature of the radiator 4 (radiator temperature TCI) can be expanded in a range that can be taken while maintaining the dehumidifying performance of the heat absorber 9 in the dehumidifying / cooling mode. It is possible to contribute to energy saving. Further, since the target blowing temperature TAO of the air supplied to the vehicle interior can be easily established, the air conditioning performance in the vehicle interior can be improved and the comfort of the passenger can be improved as a whole.

The numerical values and the like shown in each embodiment are not limited to those, and should be appropriately set according to the device to be applied. Further, the auxiliary heating device is not limited to the auxiliary heater 23 shown in the embodiment, but is used in a heat medium circulation circuit that circulates a heat medium heated by the heater to heat the air in the air flow passage 3, or an engine. A heater core or the like that circulates the heated radiator water may be used.

1 Vehicle air conditioner 2 Compressor 3 Air flow passage 4 Heater 6 Outdoor expansion valve 7 Outdoor heat exchanger 8 Indoor expansion valve 9 Heat absorber 10 HVAC unit 11 Control unit 20 Air conditioning controller 27 Indoor blower (blower fan)
28 Air mix damper 32 Heat pump controller 41 Blow-out temperature sensor 65 Vehicle communication bus R Refrigerant circuit

Claims (6)

A compressor that compresses the refrigerant and
An air flow passage through which the air supplied to the passenger compartment flows, and
A radiator for radiating the refrigerant and heating the air supplied from the air flow passage to the passenger compartment,
A heat absorber for absorbing heat from the refrigerant and cooling the air supplied from the air flow passage to the vehicle interior.
An outdoor heat exchanger installed outside the vehicle interior to dissipate heat from the refrigerant,
An outdoor expansion valve for reducing the pressure of the refrigerant flowing into the outdoor heat exchanger,
An indoor expansion valve for reducing the pressure of the refrigerant flowing into the heat absorber,
Equipped with a control device
With the control device, at least the refrigerant discharged from the compressor is radiated by the radiator and the outdoor heat exchanger, the radiated refrigerant is decompressed by the indoor expansion valve, and then the heat is absorbed by the heat absorber. In a vehicle air conditioner that executes a cooling mode
In the dehumidifying / cooling mode, the control device controls the capacity of the compressor based on the temperature of the heat absorber, and controls the valve opening degree of the outdoor expansion valve based on the temperature or pressure of the radiator. ,
An air conditioner for a vehicle, characterized in that the minimum valve opening degree of the outdoor expansion valve is changed so that the temperature distribution does not occur in the heat absorber or the temperature distribution becomes small. The control device is characterized in that the minimum valve opening degree of the outdoor expansion valve is changed so that the temperature distribution of the heat absorber satisfies a predetermined threshold value allowed for the temperature distribution of the heat absorber. The vehicle air conditioner according to 1. An indoor blower for circulating air in the air flow passage is provided.
Claim 1 is characterized in that the control device changes the minimum valve opening degree of the outdoor expansion valve in a direction of increasing the amount of ventilation to the heat absorber by the indoor blower as the amount of ventilation increases. Alternatively, the vehicle air conditioner according to claim 2. Claims 1 to claim that the control device changes the minimum valve opening degree of the outdoor expansion valve in a direction of decreasing the valve opening degree as the valve opening degree increases, based on the valve opening degree of the indoor expansion valve. The vehicle air conditioner according to any one of item 3. In the dehumidifying / cooling mode, the control device controls the capacity of the compressor based on the temperature of the heat absorber and the target temperature of the heat absorber, and also controls the capacity of the compressor.
The vehicle air conditioning according to any one of claims 1 to 4, wherein the minimum valve opening degree of the outdoor expansion valve is changed in the direction of decreasing the target temperature of the heat absorber. apparatus. The vehicle air conditioner according to any one of claims 1 to 5, wherein the control device has a predetermined hysteresis when changing the minimum valve opening degree of the outdoor expansion valve. ..

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