Vehicle air-conditioning device

Abstract

There is disclosed a vehicle air-conditioning device in which a heating qualification by gas injection can sufficiently be obtained. The vehicle air-conditioning device comprises a compressorwhich compresses a refrigerant, an air flow passagethrough which air to be supplied into a vehicle interior flows, a radiatordisposed in the air flow passage to let the refrigerant radiate heat, a heat absorberdisposed in the air flow passage to let the refrigerant absorb heat, an outdoor heat exchangerdisposed outside the vehicle interior to let the refrigerant radiate or absorb heat, and a controller. The controller executes a heating mode in which the refrigerant discharged from the compressorradiates heat in the radiatorand the refrigerant by which heat has been radiated is decompressed and then absorbs heat in the outdoor heat exchanger. The vehicle air-conditioning device comprises an injection circuitwhich distributes a part of the refrigerant flowing out from the radiatorto return the refrigerant to the middle of compression by the compressor, and the injection circuithas an expansion valve, and a discharge side heat exchangerwhich performs heat exchange between the refrigerant decompressed by the expansion valveand the refrigerant discharged from the compressorbefore flowing into the radiator