PURPOSE: To improve reliability of a compressor without damaging indoor comfortability as well as to carry out energy saving drive on an air conditioner of an automobile.

CONSTITUTION: This is as regards a freezing cycle of a heat pump type equipped with a closed type electric compressor 1 installed with an inclination sensor 5, a four-way valve 10, an outdoor heat exchanger 11, an electric expansion valve 9 and an indoor heat exchanger 12 as freezing cycle main parts. A piping on the discharge side of the closed type electric compressor 1 and a piping on the suction side are connected to each other. A piping installed with an electromagnetic valve 6 is provided, furthermore an electromagnetic valve 8 is provided on a piping part to connect the closed type electric compressor 1 and the indoor heat exchange 12 to each other, an electric expansion valve 9 is provided on a piping part to connect the indoor heat exchanger 12 and the outdoor heat exchanger 11 to each other, and an electromagnetic valve 7 is set on a piping part to connect the outdoor heat exchanger 11 and the closed type electric compressor 12 to each other.