| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a ball screw device that enables smooth circulation of balls by eliminating a step at a boundary portion between a load ball passage and direction change routes. <P>SOLUTION: The ball screw device is constituted of a screw shaft formed with a first spiral ball rolling groove at its outer peripheral surface, and a nut member 3 screwed to the screw shaft via a large number of the balls. A ball return hole substantially parallel with the screw shaft is penetratively formed at the nut member 3, the end of the ball return hole and the end of a second ball rolling groove 12 are connected to each other, a pair of the direction change routs constituting a ball infinite circulation path is formed so as to extend in the tangential direction of a through hole 40, an end plate 5 having a circulation part 51 formed with a guide groove 45 is attached to a nut body 4 at which an opened groove 47 is formed so as to continue to the second ball rolling groove 12, and thus the direction change routes are formed of the opened groove 47 and the guide groove 45 which are oppositely arranged. <P>COPYRIGHT: (C)2013,JPO&INPIT |
