| 摘要 |
A ball screw apparatus (1) which can suppress retaining pieces (10) from contacting a wall of a ball rolling path (T) or ball circulating path (J), and suppress the retaining pieces (10) between the balls (5) from falling down, so that such a ball screw apparatus (1) can be offered which enables to more improve low noises, operationability and endurance. The holding piece is rounded at an edge portion opposite to the ball (5), such that a radius of curvature of the edge portion is defined to be 1 mm or less, and the outer diameter of the retaining piece is determined to range 0.60 times or more to 0.85 times or less of the diameter of the ball. <IMAGE> |
