| 摘要 |
<p>Provided is a vehicle air-conditioning device capable of preventing a decline in the amount of coolant discharged from a compressor when in a low-outside-temperature environment, obtaining the necessary heating capability when performing a heating operation, and dehumidifying without causing a decline in heating capability when performing a dehumidifying-and-heating operation. The vehicle air-conditioning device is provided with: a bypass circuit (31; coolant channels (20l, 20m)) for causing some of the coolant discharged from a radiator (15) to be drawn into a compressor (21), when performing a heating operation or a dehumidifying-and-heating operation; a second-internal-heat-exchanger expansion valve (29) for decompressing coolant passing through the bypass circuit (31); and a second internal heat exchanger (25) for performing a heat exchange between the coolant passing through the bypass circuit (31) and decompressed by the second-internal-heat-exchanger expansion valve (29), and the rest of the coolant discharged from the radiator (15). Therein, coolant which has entered a gas-liquid two-phase state is drawn into the section of the compressor (21) through which the coolant flows during compression.</p> |
