| 摘要 |
This ball screw is provided with: a nut (1) that has a spiral groove formed on the inner peripheral surface thereof; a screw shaft (2) that has a spiral groove formed on the outer peripheral surface thereof; a ball that is arranged between tracks that are formed by the spiral groove of the nut and the spiral groove of the shaft; and a ball return path that returns the ball from the end point of the tracks to the start point thereof. The nut (1) comprises a protruding section (13) that protrudes from an axial-direction end surface thereof. The ball return path is a recessed section that is formed on the inner peripheral surface of the nut. The displacement of the nut (1) from the rotational center line of gravity that is caused by the protruding section (13) is made smaller by the configuration of the recessed section. |
