A vehicle air conditioning device which is capable of inhibiting liquid return to a compressor and generation of noise due to bumping in an accumulator. There are executed a heating mode to close a solenoid valve 17, open a solenoid valve 21, let a refrigerant from a compressor 2 radiate heat in a radiator 4, decompress the refrigerant through an outdoor expansion valve 6, let the refrigerant absorb heat in an outdoor heat exchanger 7, and send the refrigerant to an accumulator 12, and a dehumidifying and cooling mode to open the solenoid valve 17, close the solenoid valve 21, decompress the refrigerant through an indoor expansion valve 8, let the refrigerant absorb heat in a heat absorber, and send the refrigerant to the accumulator. When shifting from the heating mode to the dehumidifying and cooling mode, the solenoid valve 21 is opened for a predetermined period of time.

A vehicle air conditioner which is capable of inhibiting liquid return to a compressor and generation of noise due to bumping in an accumulator. There are executed a heating mode to close a solenoid valve 17, open a solenoid valve 21, let a refrigerant radiate heat in a radiator 4, decompress the refrigerant through an outdoor expansion valve 6, let the refrigerant absorb heat in an outdoor heat exchanger 7, and send the refrigerant to an accumulator 12, and a dehumidifying and heating mode to open the solenoid valve 17, close the solenoid valve 21, decompress the refrigerant through an indoor expansion valve 8, let the refrigerant absorb heat in a heat absorber, and generate heat in an auxiliary heater 23. A valve position of the outdoor expansion valve 6 is reduced for a predetermined period of time before shifting from the heating mode to the dehumidifying and heating mode.

The invention relates to a displacement machine according to the spiral principle, in particular a scroll compressor or scroll expander, with a high-pressure chamber, a low-pressure chamber and an orbiting displacement spiral, which engages in a counter-spiral such that chambers are formed between the displacement spiral and the counter-spiral for receiving a working medium, wherein a counter-pressure chamber is formed between the low-pressure chamber and the displacement spiral. According to the invention a pressure regulating device which is fluidically connected to the counter-pressure chamber sets a pressure difference between the counter-pressure chamber and the low-pressure chamber by means of a set value specified by the computing unit.

There is disclosed a vehicle air conditioning device which inhibits generation of noise in a solenoid valve 30 disposed on an inlet side of a radiator 4 and improves durability of the solenoid valve. A second operation mode is executed to shut off an outdoor expansion valve 6, close the solenoid valve 30, open a solenoid valve 40 and thereby send a refrigerant discharged from a compressor 2 through a bypass pipe 35 to an outdoor heat exchanger 7. When a first operation mode to open the solenoid valve 30 and close the solenoid valve 40 and thereby send the refrigerant to the radiator 4 is shifted to the second operation mode, a controller opens the solenoid valve 30 at a timing to stop the compressor 2.

A method for adaptive power engine control of a transport refrigeration unit (TRU) is provided. The method includes determining a current compressor power of a compressor of the TRU. The method also includes determining an adaptive compressor power error of the compressor. Also, the method includes calculating and setting a target compressor power of the compressor based on the current compressor power and the adaptive compressor power error. Further, the method includes determining a suction pressure control point of the compressor based on the target compressor power and a compressor curve map. Moreover, the method includes operating the compressor with the suction pressure control point of the compressor.

A refrigeration unit includes an evaporator circulating a flow of refrigerant therethrough to cool a flow of compartment air flowing over the evaporator, a compressor in fluid communication with the evaporator to compress the flow of refrigerant, an engine operably connected to the compressor to drive operation of the compressor, an expansion device in fluid communication with the flow of refrigerant, and a controller operably connected to at least the engine and the expansion device. The controller is configured to determine an available power to drive the compressor, determine a compressor discharge pressure upper limit based on the available power, compare the compressor discharge pressure upper limit to a requested compressor discharge pressure, and initiate adjustment of the expansion device such that an actual compressor discharge pressure is the lesser of the requested compressor discharge pressure or the compressor discharge pressure upper limit.

A vehicle air conditioning apparatus is provided that can extend the mileage of a vehicle by reducing the power consumed by the operation of a compressor and a heater. When a required quantity of heating Q_req is acquired, the minimum power sharing ratio between quantity of heat release Q_hpof a water-refrigerant heat exchanger 22 and quantity of heat release Q_htrof a water heater 32 is calculated, which allows the power consumption W_total to be minimized, and a compressor 21 and the water heater 32 are operated based on the result of the calculation.

A vehicle air conditioning apparatus is provided that can extend the mileage of a vehicle by reducing the power consumed by the operation of a compressor and a heater. When a required quantity of heating Q_req is acquired, the minimum power sharing ratio between quantity of heat release Q_hpof a water-refrigerant heat exchanger 22 and quantity of heat release Q_htrof a water heater 32 is calculated, which allows the power consumption W_total to be minimized, and a compressor 21 and the water heater 32 is operated based on the result of the calculation.

A torque estimating device of a gas compressor includes a reference torque characteristic storage unit that stores a reference torque characteristic of the gas compressor as a torque characteristic of the gas compressor in a specific operation state, a torque setting unit that sets a torque corresponding to an input speed of rotation of the gas compressor and pressure of a refrigerant discharged from the gas compressor, on the basis of the reference torque characteristic stored in the reference torque characteristic storage unit, and a torque correcting unit that sets a torque at startup of the gas compressor among the torques set by the torque setting unit, by correcting the torque set by the torque setting unit, in accordance with the speed of rotation and an elapsed time from startup.

An air-conditioner may include an evaporator, a compressor configured to compress refrigerant supplied to the evaporator and a clutch configured to transmit power needed to operate the compressor to the compressor or to prevent power from being supplied to the compressor, wherein the clutch prevents power from being supplied to the compressor when an actual measurement temperature of the evaporator reaches a lower limit threshold temperature selected among the lower limit threshold temperature and an upper limit threshold temperature and the lower limit threshold temperature is changeable, and the upper limit threshold temperature is relatively higher than the lower limit threshold temperature and is changeable.