| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a heat-pump vehicular air conditioner that shares with the existing vehicular air conditioner having the original cooling cycle, circuits and equipment and the like having the same pressure conditions as those of the original cooling cycle of the existing vehicular air conditioner, and that is obtained only by adding a minimum amount of heating circuits and equipment to the existing vehicular air conditioner, and that is therefore inexpensive and excellent in mountability, and that can solve the problem occurring in frost formation on a vehicle exterior evaporator and that is therefore suitable for an electric vehicle etc., and to provide a defrosting method of the heat-pump vehicular air conditioner. <P>SOLUTION: A second heating circuit 34 including an in-vehicle condenser 9, a first heating circuit 29, a second expansion valve 31 and the vehicle exterior evaporator 32 is additionally provided in a cooling refrigeration cycle 27 of the existing vehicular air conditioner, consequently a heat pump cycle 35 for heating is configured in which circuits and equipment and the like having the same pressure conditions as those of the cooling cycle 27 are shared. When frost formation is detected on the vehicle exterior evaporator 32 at the heating time by the heat pump cycle 35 for heating, refrigerant flow to the second heating circuit 34 is interrupted, and the refrigerant is flowed to an in-vehicle evaporator 8, and the heat-pump vehicular air conditioner is switched to defrosting heating utilizing the in-vehicle evaporator 8. <P>COPYRIGHT: (C)2012,JPO&INPIT</p> |
