PURPOSE: To prevent the occurrence of a vibration due to a refrigerant pump, and stably support the refrigerant pump by integrally fixing the pump to a compressor of large mass resiliently supported with a buffer spring, and positioning the pump at the opposite side of an accumulator fastened to the compressor.

CONSTITUTION: A refrigerant pump 14 is integrally fixed to a compressor 2 supported with a buffer spring 15, using fixtures 16. Also, the pump 14 is fixed at the opposite side of an accumulator 10. In this way, the pump 14 is fixed to the compressor 2 having large mass, and the compressor 2 itself is supported with the buffer spring 15, thereby enabling the vibration of the pump 14 to be dampened effectively. Furthermore, the weight balance of the compressor 2 itself can be improved by fixing the pump 14 at the opposite side of the accumulator 10.