Patent ID: 6945050

Claim:
A rotary fluid machine comprising a rotor chamber ( 14 ) formed in a casing ( 11 ), a rotor ( 41 ) rotatably housed within the rotor chamber ( 14 ), and a plurality of vane piston units supported on the rotor ( 41 ) so as to be radially movable, the vane piston units including a vane ( 48 ) that slides within the rotor chamber ( 14 ) and is guided by a vane channel ( 49 ) formed in the rotor ( 41 ), a piston ( 47 ) that is slidably fitted in a cylinder ( 44 ) provided in the rotor ( 41 ), and a roller ( 71 ) that rollably engages with an annular channel ( 74 ) formed in the casing ( 11 ), the rotary fluid machine interconverting pressure energy of a gas-phase working medium and rotational energy of the rotor ( 41 ) via the roller ( 71 ) and the annular channel ( 74 ) by reciprocation of the pistons ( 47 ) and interconverting the pressure energy of the gas-phase working medium and the rotational energy of the rotor ( 41 ) by rotation of the vanes ( 48 ); characterized in that the roller ( 71 ) is supported via a hydrostatic bearing ( 70 ) employing a liquid-phase working medium, and a portion of the liquid-phase working medium that is supplied to another hydrostatic bearing is supplied to the hydrostatic bearing ( 70 ) that supports the roller ( 71 ).