Helium compressor apparatus

摘要

A helium compressor apparatus wherein a compressor and a motor driving the compressor are disposed in a hermetically-sealed casing and helium gas is used as a refrigerant. The helium compressor apparatus of the invention comprises a separate cooling system attached to the compressor apparatus which forcibly cools down a part of the high-pressure gas discharged outside the casing by the compressor. The cooled down portion of the gas is reintroduced into the casing to cool down the compressor and the motor effectively and to thereby lengthen the life of the helium compressor apparatus.