摘要 |
A composite motion guiding unit comprises a shaft provided with helical ball screw grooves formed in the outer peripheral surface thereof and ball spline grooves formed in the outer peripheral surface thereof so as to extend in the axial direction of the shaft across the ball screw grooves and a ball screw nut and a ball spline outer cylinder both mounted on the shaft to be engageable with the ball screw grooves and ball spline grooves respectively through a number of balls. The ball screw nut and the ball spline outer cylinder are both supported by a housing to be rotatable through bearings and are driven by driving means to rotate the same, thus constituting a composite motion guiding apparatus. The ball screw grooves and the ball spline grooves have depths equal to each other. |