There is disclosed an air-conditioning apparatus for vehicle which is capable of selecting an appropriate operation mode while inhibiting the operation mode from being unnecessarily changed, and achieving rapid and stable vehicle interior air conditioning. A controller has respective operation modes of a heating mode, a dehumidifying and heating mode, a dehumidifying and cooling mode, and a cooling mode, and selects and executes these operation modes. The controller has a dehumidifying and heating mode maximum radiator temperature MAP and a dehumidifying and cooling mode maximum radiator temperature MAP. The controller selects an operation mode in which a radiator target temperature TCO is achievable by heat radiation in a radiator 4 with reference to each MAP, on startup or at a time of change of the operation mode.

An air conditioning system of a vehicle having an internal combustion engine includes a condenser configured to receive refrigerant output by an electric compressor and transfer heat from the refrigerant within the condenser to air passing the condenser. A first evaporator is configured to receive refrigerant from the condenser when a first control valve is open and transfer heat from air passing the first evaporator to the refrigerant within the first evaporator. A first blower is configured to blow air across the first evaporator to a first section of a cabin of the vehicle. A second evaporator is configured to receive refrigerant from the condenser when a second control valve is open and transfer heat from air passing the second evaporator to the refrigerant within the second evaporator. A second blower is configured to blow air across the second evaporator to a second section of the cabin of the vehicle.

An air conditioning system of a vehicle having an internal combustion engine includes a condenser configured to receive refrigerant output by an electric compressor and transfer heat from the refrigerant within the condenser to air passing the condenser. A first evaporator is configured to receive refrigerant from the condenser when a first control valve is open and transfer heat from air passing the first evaporator to the refrigerant within the first evaporator. A first blower is configured to blow air across the first evaporator to a first section of a cabin of the vehicle. A second evaporator is configured to receive refrigerant from the condenser when a second control valve is open and transfer heat from air passing the second evaporator to the refrigerant within the second evaporator. A second blower is configured to blow air across the second evaporator to a second section of the cabin of the vehicle.

An air conditioning system of a vehicle having an internal combustion engine includes a condenser configured to receive refrigerant output by an electric compressor and transfer heat from the refrigerant within the condenser to air passing the condenser. A first evaporator is configured to receive refrigerant from the condenser when a first control valve is open and transfer heat from air passing the first evaporator to the refrigerant within the first evaporator. A first blower is configured to blow air across the first evaporator to a first section of a cabin of the vehicle. A second evaporator is configured to receive refrigerant from the condenser when a second control valve is open and transfer heat from air passing the second evaporator to the refrigerant within the second evaporator. A second blower is configured to blow air across the second evaporator to a second section of the cabin of the vehicle.

An air conditioning system of a vehicle having an internal combustion engine includes a condenser configured to receive refrigerant output by an electric compressor and transfer heat from the refrigerant within the condenser to air passing the condenser. A first evaporator is configured to receive refrigerant from the condenser when a first control valve is open and transfer heat from air passing the first evaporator to the refrigerant within the first evaporator. A first blower is configured to blow air across the first evaporator to a first section of a cabin of the vehicle. A second evaporator is configured to receive refrigerant from the condenser when a second control valve is open and transfer heat from air passing the second evaporator to the refrigerant within the second evaporator. A second blower is configured to blow air across the second evaporator to a second section of the cabin of the vehicle.

An air conditioning system of a vehicle having an internal combustion engine includes a condenser configured to receive refrigerant output by an electric compressor and transfer heat from the refrigerant within the condenser to air passing the condenser. A first evaporator is configured to receive refrigerant from the condenser when a first control valve is open and transfer heat from air passing the first evaporator to the refrigerant within the first evaporator. A first blower is configured to blow air across the first evaporator to a first section of a cabin of the vehicle. A second evaporator is configured to receive refrigerant from the condenser when a second control valve is open and transfer heat from air passing the second evaporator to the refrigerant within the second evaporator. A second blower is configured to blow air across the second evaporator to a second section of the cabin of the vehicle.

An inside-outside air switching unit includes a switching member in an inside-outside air case and a drive unit that is configured to operate the switching member. The switching member is configured to open and close an outside-air inlet and an inside-air inlet. The switching member includes a first switching door and the second switching door. The first switching door is configured to be positioned by the drive unit to open the outside-air inlet in the inside-outside air intake mode. The second switching door is configured to be positioned by the drive unit to open the inside-air inlet in the inside-outside air intake mode. The drive unit is configured to move the first switching door to close an inside-outside communication passage, which is defined in the inside-outside case between the outside-air inlet and the inside-air inlet, in the inside-outside air intake mode.

Vehicle air conditioner avoids operation when short of refrigerant or oil due to backflow of refrigerant from an outdoor expansion valve to a radiator and which previously prevents lowering of air conditioning performance or deterioration of reliability. A first operation mode sends, to radiator 4, refrigerant discharged from compressor 2. A second operation mode shuts off outdoor expansion valve 6 and sends refrigerant directly into outdoor heat exchanger 7, passing the radiator and the outdoor expansion valve with bypass device 45. In the second operation mode, based on difference Pdc between pressures on outlet and inlet sides of the outdoor expansion valve 6, a controller controls a number of revolutions of compressor 2 so that pressure difference Pdc is not in excess of a predetermined reverse pressure limit ULPdcH of outdoor expansion valve 6.

A vehicle air conditioning apparatus is provided that can prevent temperature variations of the air after the heat exchange in a radiator to reliably control the temperature of the air supplied to the vehicle interior. During the heating operation and the heating and dehumidifying operation, target degree of supercooling SCt when target air-blowing temperature TAO is a predetermined temperature or higher is set to SCt1 that is greater than SCt2 when the target air-blowing temperature TAO is lower than the predetermined temperature. When amount of air Ga supplied from indoor fan 12 is lower than a predetermined value, the target degree of supercooling SCt is corrected, which is set such that the degree of supercooling is lower than target degree of supercooling corrected when the amount of air Ga supplied from the indoor fan 12 is a predetermined value or higher.

A vehicle climate control system has a control strategy which controls temperature of an evaporator in a refrigeration circuit to achieve a target temperature/relative humidity within a comfort zone which is defined by upper and lower temperature boundaries and upper and lower relative humidity boundaries. Several system embodiments are disclosed, including an all-electric system. All systems operate with improved efficiency.