Patent ID: 6467296
Filing Date: 2002-10-22
Classification: B60H,F04B,F25B

Abstract:
An air conditioning apparatus used for a vehicle, the apparatus comprising:a compressor, wherein the compressor includes: a first cylinder bore; a second cylinder bore, wherein the second cylinder bore is smaller in diameter than the first cylinder bore; a first piston located in the first cylinder bore; a second piston located in the second cylinder bore; an intermediate chamber connecting the first and second cylinder bores to one another; a suction chamber connected to the first cylinder bore; a discharge chamber connected to the second cylinder bore; a drive mechanism for driving the first and second pistons; a first intake valve for conducting refrigerant from the suction chamber to the first cylinder bore; a first exhaust valve for conducting refrigerant from the first cylinder bore to the intermediate chamber; a second intake valve for conducting refrigerant from the intermediate chamber to the second cylinder bore; and a second exhaust valve for conducting refrigerant from the second cylinder bore to the discharge chamber, wherein the compressor has a clearance volumetric ratio that is greater than 0.05; an internal heat exchanger located in a passenger compartment of the vehicle, wherein the internal heat exchanger has first and second ends; an external heat exchanger located outside the passenger compartment, wherein the external heat exchanger has first and second ends; a heat exchanger change-over circuit including: a cooling passage, by which the suction chamber of the compressor is connected to the first field of the internal heat exchanger and by which the discharge chamber is connected to the first end of the external heat exchanger; and a heating passage, by which the discharge chamber of the compressor is connected to the first end of the internal heat exchanger and by which the suction chamber is connected to the first end of the external heat exchanger, wherein the cooling passage is blocked and the heating passage is open during a heating operation, and the heating passage is blocked and the cooling passage is open during a cooling operation; and an expansion valve change-over circuit including: a heating expansion passage to expand refrigerant flowing from the internal heat exchanger; and a cooling expansion passage to expand refrigerant flowing from the external heat exchanger, wherein the heating expansion passage is open and the cooling expansion passage is closed during the heating operation, and the cooling expansion passage is open and the heating expansion passage is closed during the cooling operation.