| 摘要 |
<p>To improve workability and sealing performance of a coolant when a plurality of nuts in a ball screw are brought into contact with one another, the plurality of nuts being coupled to one another, assembled to one threaded shaft and cooled by flowing the coolant through through-holes formed in the plurality of nuts in axial directions of the plurality of nuts. The ball screw (1) includes counterbores (4, 5) of the through-holes (3) formed on opposing end faces of both of adjoining nuts (21, 22), and a ring-shaped sealing member (6) inserted thereto. The counterbores (4, 5) are formed such that a depth (D2) of one counterbore is larger than a length of the sealing member (6) (D2 > L), and the a depth (D1) of the other counterbore is smaller than the length of the sealing member (6) (D1 < L), and such that circumferential positions of the counterbore (4, 5) of the adjoining nuts (21, 22) face each other when a desired preload is exerted.</p> |
