To solve a problem that working fluid shut in a first stage working chamber in an instance of completion of communication between the first stage working chamber and a second stage working chamber exist and loss and noise are generated by compression action of the working fluid in former two stage rotary type expanders.
This two stage rotary type expander 101 is provided with a valve piston 126, and a cylindrical valve cylinder 125 storing a valve spring 127 arranged at a back surface of the valve piston 126 at an upper bearing member 107, and is provided with a valve back pressure supply path 130 leading intake pressure to a back surface side of the valve piston 126, and an intake pressure supply path 131 at a side surface side of the valve piston 126. Consequently, working fluid shut in the first delivery side space 115b is discharged to the valve cylinder 125 when pressure in the first delivery side space 115b gets higher than intake pressure.
WADA MASANOBU
TAGUCHI HIDETOSHI
OYAGI SHINGO
SAKUMA FUMIYORI
Hiroki Naito
Daisuke Nagano
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