Rolling element spacer in rolling guide device

Abstract

There is provided a rolling element spacer used in a rolling guide device having an endless circulation passage of balls, arranged alternately with many balls in the endless circulation passage, and circulating together with the balls in the endless circulation passage. It has a pair of ball holding seats each of which is formed in a concave spherical face form nearly approximating a spherical face of the ball and sliding-contacts with the ball and, around each ball holding seat, there is formed an annular dropout prevention portion protruding in a ball arranging direction than an edge portion of the ball holding seat and kept in non-contact with respect to the ball seated on the ball holding seat.

What is claimed is:  
     
         1 . A rolling element spacer used in a rolling guide device in which a pair of members perform a relative continuous motion through an endlessly circulating ball row, interposed between balls mutually adjoining in its endless circulation passage, and circulating together with the balls, 
 characterized in that it has a pair of ball holding seats each of which is formed in a concave spherical face form nearly approximating a spherical face of the ball and sliding-contacts with the ball, and    around each ball holding seat, there is formed an annular dropout prevention portion protruding in a ball arranging direction than an edge portion of the ball holding seat and kept in non-contact with respect to the ball seated on the ball holding seat.    
     
     
         2 . A rolling element spacer set forth in    claim 1   , characterized in that an annular groove is formed between the ball holding seat and the dropout prevention portion, and the annular groove functions as a lubricating oil sump.  
     
     
         3 . A rolling element spacer set forth in    claim 1   , characterized in that a lubricating oil sump is formed in the ball holding seat.  
     
     
         4 . A rolling element spacer set forth in    claim 1   , characterized in that the ball holding seat and the dropout prevention portion are molded by different resin materials, and the dropout prevention portion is molded by the resin material harder than the ball holding seat.