Turbo compressor and turbo refrigerator

Abstract

Provided is a turbo compressor configured to compress a gas in cooperation with a rotatable impeller and a diffuser formed around the impeller and to discharge the compressed gas to the outside thereof through a scroll chamber communicating with the diffuser, the turbo compressor including: an impeller casing which is formed by integrally molding a body portion surrounding the impeller and forming a part of a the scroll chamber and a partition plate provided at the rear surface side of the impeller; and a shroud cover which is provided at the inside of the body portion to surround the impeller and forming the scroll chamber in cooperation with the body portion.

1 . A turbo compressor configured to compress a gas in cooperation with a rotatable impeller and a diffuser formed around the impeller and to discharge the compressed gas the outside thereof through a scroll chamber communicating with the diffuser, the turbo compressor comprising:
 an impeller casing which is formed by integrally molding a body portion surrounding the impeller and forms a part of a the scroll chamber and a partition plate provided at the rear surface side of the impeller; and   a shroud cover which is provided at the inside of the body portion to surround the impeller and forming the scroll chamber in cooperation with the body portion.   
     
     
         2 . The turbo compressor according to  claim 1 ,
 wherein the body portion includes an inner peripheral surface contacting the shroud cover, and   wherein the shroud cover includes an annular fitting frame portion fitted to the inner peripheral surface, an annular shroud portion provided at the inside of the fitting frame portion with a predetermined gap between the shroud portion and the impeller, and a partition plate facing portion connecting the fitting frame portion and the shroud portion to each other and forming the diffuser in cooperation with the partition plate.   
     
     
         3 . The turbo compressor according to  claim 2 ,
 wherein at least a part of the fitting frame is closely fitted to the inner peripheral surface.   
     
     
         4 . The turbo compressor according to  claim 2 ,
 wherein the shroud cover includes a plurality of reinforcement portions connecting the fitting frame portion and the shroud portion to each other and extending in the radial direction of the shroud portion.   
     
     
         5 . The turbo compressor according to  claim 1 , further comprising:
 an adjustment portion which adjusts the position of the shroud cover with respect to the impeller casing in the rotation axis direction of the impeller.   
     
     
         6 . The turbo compressor according to  claim 2 ,
 wherein the inner peripheral surface of the scroll chamber is formed by a part of the outer peripheral surface of the shroud cover and a part of the inner peripheral surface of the body portion, and   wherein the inner peripheral surface portion of the scroll chamber formed by the outer peripheral surface of the shroud cover is disposed closer to the rotation shaft of the impeller than the inner peripheral surface portion of the scroll chamber formed by the inner peripheral surface of the casing body portion, and protrudes toward the diffuser along the inner peripheral surface of the scroll chamber.   
     
     
         7 . The turbo compressor according to  claim 1 ,
 wherein the shroud cover further includes a suction port suctioning a gas toward the impeller, and   wherein the shroud cover is inserted from the suction port into the body portion, and is fixed to the body portion at the side of the suction port.   
     
     
         8 . The turbo compressor according to  claim 1 ,
 wherein the diffuser is formed by the impeller casing and the shroud cover.   
     
     
         9 . A turbo refrigerator comprising:
 a condenser which cools and liquefies a compressed refrigerant;   an evaporator which evaporates the liquefied refrigerant and takes evaporation heat from a cooling object to cool the cooling object; and   a compressor which compresses the refrigerant evaporated from the evaporator and supplies the compressed refrigerant to the condenser,   wherein the turbo compressor according to  claim 1  is used as the compressor.