HEAT PUMP AIR-CONDITIONING SYSTEM FOR VEHICLE

摘要

Provided is a heat pump air-conditioning system for a vehicle that is capable of ensuring a temperature linearity characteristic during dehumidifying heating, slowing the progression of frost formation on an exterior evaporator during heating, and stably continuing the heating operation while suppressing fluctuations in blowout temperature. An interior condenser (8) provided inside an HVAC unit (2) is connected via a switching means (15) in parallel to an exterior condenser (10) for a cooling refrigeration cycle (14) serving as a base cycle, an exterior evaporator (17) is connected via a second decompression means (16) in parallel to a first decompression means (12) and an interior evaporator (7) so as to form a heating heat pump cycle (18), and the first decompression means (12) and the second decompression means (16) are provided with an on-off valve function. Consequently, this configuration allows the exterior evaporator (17) and the interior evaporator (7) to be simultaneously used during dehumidifying heating and during heating.