Turbo compressor and refrigerator with the compressor

Abstract

A turbo-type compressor having an improved performance which may be produced without increasing its size or cost, and the performance of a refrigeration unit is also improved when it is provided with such a turbo-type compressor. The turbo-type compressor includes a casing ( 55 ) provided with an intake opening and a discharge opening; a rotation shaft ( 41 ) operated by a driving mechanism; an impeller ( 19 ) provided integrally with the rotation shaft ( 41 ); a diffuser section ( 46 ) constituted by a pair of a first wall section ( 56 ) and a second wall section ( 58 ), located at the outer periphery side of the impeller ( 19 ) to serve as a fluid passage for a refrigerant driven towards the outer side by the rotation action of the impeller ( 19 ). The refrigerant is drawn in through the intake opening, by the action of the impeller ( 19 ) which is rotated together with the rotation shaft ( 41 ) and driven by a motor, to be compressed and discharged through the outlet opening. In this compressor, the diffuser section ( 46 ) is constructed in such a way that the width dimension in the axial direction of the outlet opening ( 46 b ) is made larger than the width dimension of the inlet opening ( 46 a ).

1 . A refrigeration apparatus, comprising: a compressor for compressing a refrigerant admitted from an intake opening and discharging the refrigerant from a discharge opening; a condenser for condensing and liquefying the refrigerant and forwarding a resultant liquefied refrigerant; a throttling mechanism for reducing the pressure of the liquefied refrigerant; and a vaporizer for cooling an object to be cooled by exchanging heat between the object to be cooled and a resultant condensed and pressure-reduced liquefied refrigerant, and evaporating and vaporizing the liquefied refrigerant, wherein 
 the compressor is a turbo-type compressor comprising: a casing provided with an intake opening and a discharge opening; a rotation shaft operated by a driving mechanism; an impeller provided integrally with the rotation shaft; a diffuser section comprised of a pair of wall sections at outer peripheries of the impeller to serve as a fluid passage for a fluid driven towards the outer periphery side by the rotation of the impeller so that the fluid is drawn in from the intake opening, by the action of the impeller which is rotated together with the rotation shaft and driven by the driving mechanism, to be compressed and discharged from the discharge opening through the diffuser section; wherein    the diffuser section is formed in such a way that the width dimension in the axial direction of an outlet opening located at the outer periphery side is made larger than the width dimension of an inlet opening for the fluid which is driven by the impeller.    
     
     
         2 . A refrigeration apparatus according to  claim 1 , wherein 
 the width dimension of the outlet opening is made larger than the width dimension of the inlet opening without altering the area ratio of the inlet opening to the outlet opening of the diffuser section.    
     
     
         3 . A refrigeration apparatus according to  claim 1 , wherein 
 the pair of wall sections forming the diffuser section is made in a tapered shape so as to separate gradually from each other from the inlet opening towards the outlet opening.    
     
     
         4 . A refrigeration apparatus according to  claim 1 , wherein 
 one of the pair of wall sections forming the diffuser section is made into a tapered shape so as to separate gradually from the other one of the pair of wall sections from the inlet opening towards the outlet opening.    
     
     
         5 . A refrigeration apparatus according to  claim 1 , wherein 
 the turbo-type compressor is a multi-stage compressor having a plurality of the impellers and compresses the fluid from the intake opening sequentially by using, first, an upstream-side impeller, and successive impellers afterward.