Patent ID: 9707930
Date: 2017-07-18
CPC Classifications: B60H,B60S,F25D

Claim:
1. An air conditioner for a vehicle comprising: a control unit; a compressor that compresses a heat exchange medium; an internal heat exchanger that performs heat exchange between the heat exchange medium expelled from the compressor and air for air conditioning introduced inside a vehicle compartment; and an external heat exchanger that performs heat exchange between the heat exchange medium expelled from the internal heat exchanger and external air, wherein said control unit is configured to: calculate a first moving average value of a temperature difference between an external air temperature and a temperature of the external heat exchanger for a first period of time; calculate a second moving average value of a temperature difference between an external air temperature and a temperature of the external heat exchanger for a second period of time; calculate a moving average value difference between the second moving average value and the first moving average value; perform a defrosting operation which melts frost adhered to the external heat exchanger when the moving average value difference is equal to or greater than a first predetermined value; wherein the air conditioner is operable to perform the defrosting operation even during the middle of the second period of time when the moving average value difference becomes equal to or greater than the first predetermined value.