| 摘要 |
<p>A ball screw device in which, even if the lead length of a rolling groove is short and the diameter of balls is large, an endless circulation path for the balls can be formed by using a return pipe (3, 6) and the joint between the return pipe (3, 6) and a loaded rolling groove (22) of a nut (2) does not adversely affect the circulation of the balls. A ball passage hole (24) is formed in the nut (2), and the ball passage hole (24) has therein a ball guide surface (27) connected without a step to an end of the loaded rolling groove (22) of the nut (2). A ball scooping section (4) extending from the return pipe (3) is inserted in the ball passage hole (24). The ball scooping section (4) faces, in the ball passage hole (24), the ball guide surface (27) to form a ball path having an inner diameter slightly greater than the diameter of the balls.</p> |
