Patent ID: 6125643
Filing Date: 2000-10-03
Classification: B60H,F25B

Abstract:
A heat pump type air conditioning system for an automotive vehicle, comprising:a compressor, an exterior condenser disposed outside a passenger compartment of the vehicle, an interior condenser disposed inside the passenger compartment, a pressure-reducing device, and an interior evaporator disposed inside the passenger compartment which are connected in series with each other through a refrigerant piping;a bypass passage which is formed bypassing said exterior condenser to allow the refrigerant discharged from said compressor to be introduced to said interior condenser bypassing said exterior condenser;a flow passage change-over device for introducing the refrigerant discharged from said compressor to said exterior condenser during a refrigeration operation of said air conditioning system and to said bypass passage during a heating operation of said air conditioning system;a refrigerant recovery passage through which the refrigerant stayed in said exterior condenser is returned to a suction side of said compressor, said refrigerant recovery passage being located to connect the outlet side of said exterior condenser and the suction side of said compressor;a valve disposed in said refrigerant recovery passage to be opened to allow the refrigerant to flow through the refrigerant recovery passage and to be closed to prevent the refrigerant from flowing through the refrigerant recovery passage, said valve being a pilot pressure differential-operated electromagnetic valve that is located to be directed to control flow of the refrigerant in a refrigerant recovery direction in which the refrigerant to be recovered flows; anda check valve disposed in said refrigerant recovery passage to prevent the refrigerant from flowing in an opposite direction to the refrigerant recovery direction, said check valve being located downstream of said pilot pressure differential-operated electromagnetic valve relative to the refrigerant recovery direction.