Fluid Machine

Abstract

A fluid machine ( 29 A) including: a casing section ( 56 ) having a suction port ( 55 ) into which a working fluid that becomes a high pressure heated vapor flows; a housing section ( 54 ) having a discharge port ( 53 ); and a scroll section ( 51, 52 ) driven by the working fluid suctioned from the suction port ( 55 ). A bypass section ( 80 ) including: a bypass passage ( 81 ) allowing the suction port ( 55 ) to communicate with the discharge port ( 53 ); and a valve mechanism ( 83 ) opening and closing the bypass passage ( 81 ), is supported between the sections ( 56, 54 ). When the bypass passage ( 81 ) is opened, the working fluid is circulated while bypassing a driving section including the scroll section ( 51, 52 ) and a sliding section such as an anti-rotation mechanism ( 60 ). Therefore, even when the working fluid in a liquid phase flows, degradation of lubricity in the sliding section can be reduced.

1 . A fluid machine comprising:
 a suction port into which a working fluid that becomes a heated vapor and has a high pressure flows;   a driving section which is driven by expansion of the working fluid suctioned from the suction port;   a discharge port from which the working fluid that has a low pressure while passing through the driving section flows; and   a bypass passage which guides the working fluid suctioned from the suction port to the discharge port while allowing the working fluid to bypass a sliding section of the fluid machine and the driving section.   
     
     
         2 . The fluid machine according to  claim 1 ,
 wherein the bypass passage is a communication passage which allows the suction port and the discharge port to communicate with each other.   
     
     
         3 . The fluid machine according to  claim 2 ,
 wherein the suction port and the discharge port extend in a radial direction of a rotating shaft of the driving section and are arranged in an axial direction of the rotating shaft, and   wherein the bypass passage extends in the axial direction of the rotating shaft of the driving section and allows the suction port and the discharge port to communicate with each other.   
     
     
         4 . The fluid machine according to  claim 3 , further comprising:
 a valve mechanism which opens and closes the bypass passage,   wherein the valve mechanism opens and closes the bypass passage by displacing a valve body in the radial direction of the rotating shaft of the driving section.   
     
     
         5 . The fluid machine according to  claim 1 ,
 wherein the fluid machine includes, as the driving section, a scroll section including a fixed scroll and an orbiting scroll, and includes, as the sliding section, an anti-rotation mechanism that prevents the orbiting scroll from rotating.   
     
     
         6 . The fluid machine according to  claim 5 ,
 wherein the fluid machine is a scroll type expander, and is incorporated in a Rankine cycle device which recovers waste heat of an engine for a vehicle for use.