Abstract: A refrigeration cycle device includes a charged-amount determination unit that executes a charged-amount determination to determine whether the refrigeration cycle device is in a refrigerant shortage state or not, a compressor control unit that controls a compressor, and a decompression control unit that controls a throttle opening degree of a decompression device. The charged-amount determination unit determines that the refrigeration cycle device is in the refrigerant shortage state when a heat dissipation capacity of a radiator shows a tendency to decrease in a case where the decompression control unit decreases a throttle opening degree of the decompression device while the compressor control unit operates the compressor.

Abstract: A refrigeration cycle device includes a charged-amount determination unit that executes a charged-amount determination to determine whether the refrigeration cycle device is in a refrigerant shortage state or not, a compressor control unit that controls a compressor, and a decompression control unit that controls a throttle opening degree of a decompression device. The charged-amount determination unit determines that the refrigeration cycle device is in the refrigerant shortage state when a heat dissipation capacity of a radiator shows a tendency to decrease in a case where the decompression control unit decreases a throttle opening degree of the decompression device while the compressor control unit operates the compressor.

Abstract: A vehicular air-conditioning system provided with a vapor compression type refrigerating machine improved in practicality, provided with a vapor compression type refrigeration cycle 10 having a compressor 11 compressing and discharging a refrigerant and an outside heat exchanger 16 exchanging heat with the air outside of the cabin and the refrigerant and designed to be able to switch between a cooler cycle cooling vented air blown into the cabin and a heat pump cycle heating the vented air, a heating means 36 for using cooling water of an internal combustion engine EG as a heat source for heating the vented air, a vent mode switch 60c setting a defogging mode blowing out vented air toward the vehicle window glass by operation by a passenger, and a control means 50 controlling switching between the cooler cycle and heat pump cycle, the control means 50 selecting the cooler cycle and outputting a signal requesting operation to the internal combustion engine EG when the vent mode switch 60c is used to set the de

Abstract: An air conditioner for a vehicle includes a vapor compression refrigeration cycle configured to have a heat pump cycle for heating air to be blown into an interior of a vehicle compartment, and a heating member for heating the air using a coolant of an internal combustion engine of the vehicle as a heat source. In the air conditioner, an operation request signal is output by an air conditioning controller to the internal combustion engine when an outside air temperature is lower than a predetermined threshold.

Abstract: A vapor-compression refrigerant cycle includes a variable displacement compressor for compressing refrigerant, a control unit for controlling the displacement of the compressor. The control unit includes a lock determining means for determining a lock of a sliding portion of the compressor, and the lock determining means determines that the sliding portion of the compressor is locked, when a control signal where the displacement of the compressor is equal to or larger than a predetermined value is output from the control unit, and when an absolute value of a temperature difference between an air temperature before being heat-exchanged in a low-pressure heat exchanger of the vapor-compression refrigerant cycle and the air temperature after being heat-exchanged in the low-pressure heat exchanger is equal to or smaller than a predetermined temperature. Therefore, the lock of the compressor can be accurately detected.

Abstract: A vapor-compression refrigerant cycle includes a variable displacement compressor for compressing refrigerant, a control unit for controlling the displacement of the compressor. The control unit includes a lock determining means for determining a lock of a sliding portion of the compressor, and the lock determining means determines that the sliding portion of the compressor is locked, when a control signal where the displacement of the compressor is equal to or larger than a predetermined value is output from the control unit, and when an absolute value of a temperature difference between an air temperature before being heat-exchanged in a low-pressure heat exchanger of the vapor-compression refrigerant cycle and the air temperature after being heat-exchanged in the low-pressure heat exchanger is equal to or smaller than a predetermined temperature. Therefore, the lock of the compressor can be accurately detected.