A superfinishing method for a bearing roller, and a superfinishing device for a bearing roller

A superfinishing method for a bearing roller, which involves installation of a pair of feed drums in parallel to each other, the pair of feed drums having guide thread surfaces each continue in a spiral shape on an outer periphery, and each being driven to rotate about respective center axes, the feed drums being configured to through-feed a workpiece that is to be formed into a bearing roller between the feed drums while supporting and rotating the workpiece with the guide thread surfaces opposed to each other, the superfinishing method including use of a grinder to process an outer peripheral surface of the workpiece passing between the feed drums, the superfinishing method comprising:

• varying a thread bottom angle of the guide thread surface in accordance with positions along the feed drums in an axial direction;
• and
• superfinishing a straight portion and logarithmic curve crowning portions at both ends of the straight portion of a rolling surface of the bearing roller by one through-feed of the workpiece passing between the feed drums.