Cross joint

Abstract

In a cross joint outwardly fitting a bearing cup to each of four pieces of shafts of a cross shaft member via a cylindrical member, race portions formed on a side of the cross shaft member and on a side of the bearing cup and a shoulder portion provided between respectives of neck portions of two of the shafts of the cross shaft member contiguous to each other are subjected to roller burnishing.

1 . A method of manufacturing a cross joint which includes: 
 a cross shaft member including, four shafts each having a neck portion and a race portion, and shoulder portions provided between adjacent two neck portions; rolling members adapted to rotate around the race portions; and outer ring members fitted to the respective shafts via the rolling members, the method comprising roller burnishing the race portions and the shoulder portions.    
   
   
       2 . The method according to  claim 1 , further comprising roller burnishing a race portion formed on the outer ring member.  
   
   
       3 . The method according to  claim 1 , wherein the cross joint comprises one of bearing steel and carbon steel for mechanical structure.  
   
   
       4 . The method according to  claim 3 , wherein the outer ring members comprise one of bearing steel and carbon steel for mechanical structure.  
   
   
       5 . A method of manufacturing a cross joint which includes: 
 a cross shaft member including four shafts each having a neck portion and a race portion, and shoulder portions provided between adjacent two neck portions; rolling members adapted to rotate around the race portions; and outer ring members fitted to the respective shafts via the rolling members, the method comprising: 
 first finishing the race portions and the shoulder portions by at least one of cutting and polishing; and  
 second roller burnishing the race portions and the shoulder portions after the first subjecting step.