PURPOSE: To improve the operational efficiency and the reliability by directly pushing up a nonreturn valve at the time of 100% operation to open a discharge passage and close the nonreturn valve by a back pressure at the time of 50% operation to intercept the discharge passage for simplifying the structure of the nonreturn valve and increasing the strength.
CONSTITUTION: A part of refrigerant gas compressed on a front side is sent into a pressure operation chamber 25, and a spool 24 is moved to the direction of a rear valve plate 10R, while a discharge valve 14R closes a discharge port 12R and an escape hole 21. This construction permits to obtain the compressing work of refrigerant gas also on the side of a rear housing 15R. Meanwhile, the refrigerant gas compressed on the side of a discharge chamber 18R like this is sent into a pressurizing chamber 30b via a connecting hole 31. When the compressed refrigerant gas is sent into the pressurizing chamber 30b, a nonreturn valve 29 is pushed up by the discharge pressure of this refrigerant gas to obtain a state to open a passage 20R.
KATOU KIMIO
OONO MAKOTO
