Shoe for swash plate type compressor and swash plate type compressor equipped with the shoe

Abstract

A shoe for a swash plate type compressor disposed between a swash plate and a corresponding one of a plurality of pistons, the shoe being characterized by comprising: a base body formed of an aluminum alloy; and a metal plating film which covers at least a portion of a surface of the base body.

What is claimed is:  
     
         1 . A shoe for a swash plate type compressor disposed between a swash plate and a corresponding one of a plurality of pistons, said shoe comprising: 
 a base body formed of an aluminum alloy; and    a metal plating film which covers at least a portion of a surface of said base body.    
     
     
         2 . A shoe according to  claim 1 , wherein said metal plating film comprises an electroless plating film which contains at least one of Ni and Co as a major constituent element.  
     
     
         3 . A shoe according to  claim 2 , wherein said electroless plating film comprises at least one electroless nickel plating film selected from the group consisting of an Ni—P based film, an Ni—B based film, an Ni—P—B based film, an Ni—P—W based film, an Ni—B—W—based film, and an Ni—P—B—W based film.  
     
     
         4 . A shoe according to  claim 2 , wherein said electroless plating film comprises at least one electroless cobalt plating film selected from the group consisting of a Co—P based film and a Co—P—W based film.  
     
     
         5 . A shoe according to  claim 2 , wherein said electroless plating film comprises at least one electroless nickel-cobalt plating film selected from the group consisting of an Ni—Co based film and an Ni—Co—P based film.  
     
     
         6 . A shoe according to  claim 2 , wherein said electroless plating film contains polytetrafluoroethylene (PTFE).  
     
     
         7 . A shoe according to  claim 2 , wherein said metal plating film further comprises at least one covering film which is formed on a surface of said electroless plating film and which contains at least one of Sn, TiCN, TiN, CrN, and TiAlN.  
     
     
         8 . A shoe according to  claim 1 , wherein said metal plating film comprises an electroplating film which contains at least one of Ni, Fe, Cr, and Co as a major constituent element.  
     
     
         9 . A shoe according to  claim 8 , wherein said electroplating film comprises at least one nickel electroplating film selected from the group consisting of an Ni based film, an Ni—P based film, an Ni—W based film, an Ni—Fe based film, an Ni—M 0 —W based film.  
     
     
         10 . A shoe according to  claim 8 , wherein said electroplating film comprises at least one ferrous electroplating film selected from the group consisting of an Fe based film, an Fe—P based film, an Fe—W based film, an Fe—C based film, and an Fe—N based film.  
     
     
         11 . A shoe according to  claim 8 , wherein said electroplating film comprises at least one chromium electroplating film selected from the group consisting of a Cr based film and a Cr—Mo based film.  
     
     
         12 . A shoe according to  claim 8 , wherein said electroplating film comprises at least one cobalt electroplating film selected from the group consisting of a Co based film and a Co—W based film.  
     
     
         13 . A shoe according to  claim 1 , wherein said metal plating film contains at least one of SiC, Si 3 N 4 , Al 2 O 3 , and CrC.  
     
     
         14 . A shoe according to  claim 1 , wherein said metal plating film has a hardness value of not smaller than Hv 300.  
     
     
         15 . A shoe according to  claim 1 , wherein said metal plating film covers at least a portion of said base body which, portion is held in sliding contact with said swash plate.  
     
     
         16 . A shoe according to  claim 1 , wherein said metal plating film constitutes at least a part of an outer surface of said shoe.  
     
     
         17 . A swash plate type compressor comprising: 
 a swash plate;    a plurality of pistons; and    a plurality of shoes as defined in  claim 1 , each of said plurality of shoes being disposed between said swash plate and a corresponding one of said plurality of pistons.    
     
     
         18 . A swash plate type compressor according to  claim 17 , wherein said swash plate is formed of a ferrous material.  
     
     
         19 . A swash plate type compressor according to  claim 17 , wherein said swash plate includes lubricating films formed on sliding surfaces thereof which slide on said plurality of shoes.  
     
     
         20 . A swash plate type compressor according to  claim 17 , further comprising a displacement capacity changing mechanism for changing a displacement capacity of said compressor by changing an inclination angle of said swash plate.