Planetary Ball Drive Mechanism : Shape of Scoop Surface of Ball and Test Result

Abstract

In the planetary ball drive mechanism the scoop surface for moving balls must be prepared at the ends of the groove of the carrier and the helical groove of a bolt. Moreover for the sake of circulation of the scooped balls two holes must be bored on a nut. The authors analyze the geometrical condition of the shape of the scoope surface and the position angle between two guide holes. The operation test was conducted under various loads and the results cleared the wear condition of the scoop surface.