Abstract: The invention provides a shape of a wall surface of a direction changing path of a roller bearing for an endless linear motion. The outer wall surfaces of the direction changing path are formed convex outward. This convex outward outer wall surface can be formed as a spherical band with its center of curvature lying on the axis of revolution of the direction changing path. Such outer wall shape allows a minimum play of the rollers of the roller bearing for an endless linear motion during the direction changing motion through the direction changing path. As a result, stick-slip motion as well as the resistance of the rollers during the direction changing motion are reduced. Accordingly, the total the resistance of the roller bearing for an endless linear motion is reduced, producing an improved roller bearing for an endless linear motion as a whole.

Abstract: A roller bearing for endless linear motion wherein a casing mounted on a track rail makes linear motion through a plurality of rollers circulating endlessly. A circulating path for the rollers is constructed by load track, return hole and direction changing path. The load track and return hole are straight, parallel to each other and approximately square shape in cross section, respectively. The center of the return hole does not lie in the horizontal bisecting plane of the right angle V groove of the load track. The return hole is symmetric to the load track with respect to the perpendicular bisector of the segment line joining the centers of the rollers in the return hole and the load track. The direction changing path is a cylindrical surface of revolution which is approximately square shape in cross section and which is formed by revolving 180.degree.