Turbo fluid machine

Abstract

A turbo fluid machine includes: a housing; an electric motor; an impeller that compresses fluid; and a drive shaft connecting the impeller and the electric motor in the housing. The impeller chamber includes a first impeller chamber and a second impeller chamber distanced from each other in an axial direction of the drive shaft. The impeller includes: a first impeller that compresses the fluid to produce first compressed fluid; and a second impeller that compresses the first compressed fluid to produce second compressed fluid. The turbo fluid machine further includes: a compressed fluid passage through which the first compressed fluid is supplied to the second impeller chamber; and a plurality of flow straightening passages that extends inside the compressed fluid passage in a direction in which the compressed fluid passage extends, and through which the first compressed fluid is straightened and supplied to the second impeller chamber.

What is claimed is: 
     
         1 . A turbo fluid machine comprising:
 a housing including an impeller chamber and a motor chamber;   an electric motor accommodated in the motor chamber,   an impeller that is accommodated in the impeller chamber and compresses fluid with rotation of the electric motor; and   a drive shaft that is accommodated in the housing and connects the impeller and the electric motor, wherein   the impeller chamber includes a first impeller chamber and a second impeller chamber distanced from each other in an axial direction of the drive shaft,   the impeller includes:
 a first impeller that is accommodated in the first impeller chamber and compresses the fluid to produce first compressed fluid; and 
 a second impeller that is accommodated in the second impeller chamber and compresses the first compressed fluid to produce second compressed fluid, and 
   the turbo fluid machine further includes:
 a compressed fluid passage through which the first compressed fluid is supplied to the second impeller chamber; and 
 a plurality of flow straightening passages that extends inside the compressed fluid passage in a direction in which the compressed fluid passage extends, and through which the first compressed fluid is straightened and supplied to the second impeller chamber. 
   
     
     
         2 . The turbo fluid machine according to  claim 1 , wherein
 each of the flow straightening passages is disposed at a position closer to the second impeller chamber than to the first impeller chamber.   
     
     
         3 . The turbo fluid machine according to  claim 1 , wherein
 each of the flow straightening passages is formed of a cylindrical body extending straight.   
     
     
         4 . The turbo fluid machine according to  claim 1 , wherein
 the compressed fluid passage includes a cooling portion configured to cool the first compressed fluid flowing through each of the flow straightening passages.