Patent ID: 6971246
Filing Date: 2005-12-06
Classification: B60H,F25B

Abstract:
1. An air conditioner for a vehicle comprising: a front air conditioning unit for air-conditioning a front area in a passenger compartment of the vehicle; a rear air conditioning unit for air-conditioning a rear area in a passenger compartment; a compressor for compressing refrigerant; a condenser for condensing gas refrigerant discharged from the compressor in a cooling mode; a front evaporator disposed in the front air conditioning unit, for cooling air in the cooling mode and for heating air in a first heating mode; a rear evaporator disposed in the rear air conditioning unit for cooling air in the cooling mode; a hot-gas bypass passage through which the gas refrigerant discharged from the compressor flows into the front evaporator while bypassing the condenser in the heating mode; a front decompression unit, disposed between the condenser and the front evaporator, for decompressing refrigerant flowing from the condenser in the cooling mode; a rear decompression unit, disposed between the condenser and the rear evaporator, for decompressing refrigerant flowing from the condenser in the cooling mode; a refrigerant pipe to which a refrigerant outlet side of the front decompression unit and a refrigerant outlet side of the hot-gas bypass passage are joined; and a low-pressure gas-liquid separator for separating refrigerant into gas refrigerant and liquid refrigerant, the low-pressure gas-liquid separator being coupled to a refrigerant outlet of the front evaporator and a refrigerant outlet of the rear evaporator, the low-pressure gas-liquid separator having a refrigerant outlet portion through which gas refrigerant is introduced to a suction port of the compressor, wherein the refrigerant pipe has a refrigerant outlet that is connected to a refrigerant inlet of the front evaporator; the condenser includes first and second heat-exchanging units which are disposed in this order in a refrigerant flow direction, and a high-pressure gas-liquid separator disposed between the first heat-exchanging unit and the second heat-exchanging unit for separating refrigerant into gas refrigerant and liquid refrigerant; the front decompression unit is a fixed throttle; the high-pressure gas-liquid separator regulates a stored amount of liquid refrigerant in response to a superheating degree of the gas refrigerant discharged from the compressor that is controlled to regulate a superheating degree of the gas refrigerant at an outlet of the front evaporator when at least the front air conditioning unit is operated under the cooling mode; the rear decompression unit regulates a superheating degree of gas refrigerant at an outlet of the rear evaporator independently from an operation of the front evaporator when the rear air conditioning unit is operated under the cooling mode; a check valve is disposed between the rear evaporator and the low-pressure gas-liquid separator so as to shut a reverse flow from the low-pressure gas-liquid separator toward the rear evaporator; the low-pressure gas-liquid separator has a first inlet coupled to the refrigerant outlet of the front evaporator and a second inlet independently formed from the first inlet and coupled to the refrigerant outlet of the rear evaporator; and the check valve is located adjacent to the second inlet.