Method of manufacturing race for rolling bearing, and apparatus therefore

Abstract

A manufacturing apparatus for the race for a thin cross-section rolling bearing from a heat-treated pipe-shaped material W with a rib section 1 at one end thereof comprises a first spindle 11 having a clamping jig 14 to clamp the rib section 1, and a chuck 12 to securely hold the clamping jig 14; a machining unit 23 to process the pipe-shaped material W to form an annular member 10 via turning and/or grinding steps; and a second spindle 28 to retain the annular member, which has been cut off from the rest of the pipe-shaped material W, so that the end face of the annular member is subjected to turning and/or grinding steps, whereby the precision in roundness and uniformity in material thickness of the race is improved.

What is claimed is:  
     
         1 . A manufacturing method for a race for a rolling bearing comprising the steps of: 
 heat-treating a pipe-shaped material formed into a cylindrical shape and provided with a rib section at one end thereof;    chucking the one end of said heat-treated pipe-shaped material via a clamping jig;    forming the other end of the heat-treated pipe-shaped material into a predetermined annular shape via turning and/or grinding to provide an annular member;    cutting off the annular member from the rest of the pipe-shaped material to provide the annular member with an end face on the cut side;    retaining the annular member on the side opposite to the cut side, and    processing the end face on the cut side of the annular member via turning and/or grinding.    
     
     
         2 . A manufacturing method for a race for a rolling bearing according to  claim 1 , wherein the forming step comprises: turning an end face of the other end opposite to the one end chucked, an external surface and an internal surface of the pipe-shaped material to form the annular member; then grinding the external surface, the end face, and the internal surface of the annular member with a groove for raceway formed on one of the external and internal surface; and the processing step comprises; turning and then grinding the end face on the cut side of the annular member.  
     
     
         3 . A manufacturing method for a race for a rolling bearing according to  claim 1 , wherein the forming step comprises: turning an end face of the other end opposite to the one end chucked, an external surface and an internal surface of the pipe-shaped material to form the annular member; and the processing step comprises; turning and then grinding the end face on the cut side of the annular member.  
     
     
         4 . A manufacturing method for a race for a rolling bearing according to  claim 1 , wherein the forming step comprises: turning an end face of the other end opposite to the one end chucked, an external surface and an internal surface of the pipe-shaped material to form the annular member, and then forming a groove for raceway in the internal surface of the annular member by grinding; and the processing step comprises; turning and then grinding the end face on the cut side of the annular member.  
     
     
         5 . A manufacturing method for a race for a rolling bearing according to  claim 1 , wherein the forming step comprises: turning an end face of the other end opposite to the one end chucked, an external surface and an internal surface of the pipe-shaped material to form the annular member; then grinding the external surface, and the internal surface of the annular member with a groove for raceway formed on one of the internal and external surfaces, and the processing step comprises; turning and then grinding the end face on the cut side of the annular member.  
     
     
         6 . A manufacturing method for a race for a rolling bearing according to any one of  claim 1  through  claim 5 , wherein the rib section of the pipe-shaped material is provided on an internal diameter side of the pipe.  
     
     
         7 . A manufacturing method for a race for rolling bearing according to any one of  claim 1  through  claim 5 , wherein the rib section of the pipe-shaped material is provided on an external diameter side of the pipe.  
     
     
         8 . A manufacturing method for a race for a rolling bearing according to any one of  claim 1  through  claim 7 , wherein the clamping jig clamps the rib section in the axial direction of the cylindrical shape of the pipe-shaped material.  
     
     
         9 . A manufacturing method for a race for a rolling bearing according to any one of  claim 1  through  claim 8 , whereby a race of the thin cross-section rolling bearing is manufactured.  
     
     
         10 . A manufacturing apparatus for a race for a rolling bearing comprising: 
 a first spindle which retains one end of a pipe-shaped material formed into a cylindrical shape and provided with a rib section at the one end thereof;    a machining unit which processes the other end of the pipe-shaped material into an annular member of a desired shape via turning and/or grinding processes; and    a cutting-off device which cuts off the annular member from the rest of the pipe-shaped material;    a second spindle which retains the annular member before and after being cut off by the cutting-off device,    said machining unit being used in order that the end on the cut side of the annular member is subjected to turning and/or grinding processing while the annular member is retained by said second spindle, and    the one end of the pipe-shaped material being formed with a rib section, and said first spindle being provided with a clamping jig which clamps the rib section of the pipe-shaped material, and a chuck which securely supports the clamping jig.    
     
     
         11 . A manufacturing apparatus for a race for a rolling bearing according to  claim 10 , wherein the machining unit comprises a first machining means which turns and grinds the pipe-shaped material and the annular member formed in the pipe-shaped material and a second machining unit which turns and grinds the annular member after being cut off.  
     
     
         12 . A manufacturing apparatus for a race for a rolling bearing according to either one of  claim 10  and  claim 11 , wherein the clamping jig is configured to clamp the rib section in the axial direction of the cylindrical shape.  
     
     
         13 . A manufacturing apparatus for a race for a rolling bearing according to  claim 12 , wherein the clamping jig is provided with a configuration for clamping a rib section provided on the internal diameter side of the pipe-shaped material.  
     
     
         14 . A manufacturing apparatus for a race for rolling bearing according to  claim 12 , wherein the clamping jig is provided with a configuration for clamping a rib section provided on the external diameter side of the pipe-shaped material.  
     
     
         15 . A manufacturing apparatus for a race for rolling bearing according to any one of  claim 10  through  claim 14 , wherein said second spindle is provided with a retaining face to mate with the annular member, and configured so as to attract and hold the annular member by magnetic force of said retaining face.  
     
     
         16 . A manufacturing apparatus for a race for rolling bearing according to any one of  claim 10  through  claim 15 , for manufacturing a race of the thin cross-section rolling bearing.  
     
     
         17 . A rolling bearing having a race which has a material thickness ratio up to 4%, and is manufactured via: 
 heat-treating a pipe-shaped material formed into a cylindrical shape and provided with a rib section at one end thereof;    chucking the one end of the heat treated pipe-shaped material via a clamping jig;    forming the other end of the chucked pipe-shaped material into a predetermined annular shape via turning and/or grinding to form an annular member;    cutting off the annular member from the rest of the pipe-shaped material to provide the annular member with an end face on the cut side; and    retaining said annular member on the side of the other end, and    turning and/or grinding the end face thereof on the cut side.    
     
     
         18 . A rolling bearing according to  claim 17 , wherein said race is provided with a chamfer section by turning.  
     
     
         19 . A rolling bearing according to either one of  claim 17  and  claim 18 , wherein the rolling bearing is of the thin cross-section type.