Spacer for linear motion apparatus and linear motion apparatus provided with spacer

摘要

A spacer (5) for a linear motion apparatus (1) is to be interposed alternately between balls (4) arranged in an endless circulation passage of the linear motion apparatus (1). The spacer (5) has a body portion comprising spherical retaining surface (11) portions formed for supporting the balls (4) on both end portions thereof in an advancing direction of the spacer (5) when moving in the endless circulation passage and a circumferential surface portion constituting an outer peripheral portion of the spherical retaining surface portions (11). The spherical retaining surface portion (11) has a radius of curvature smaller than a diameter of the ball (4) and the circumferential surface portion is provided with a groove (13) extending in the circumferential direction thereof so that one of the spherical retaining surface portions (11) is elastically deformable towards another one thereof. The spacer (5) is preferably applicable to various kinds of linear motion apparatus (1). Further, rollers as rolling members may be utilized in place of the balls (4).