| 摘要 |
PROBLEM TO BE SOLVED: To provide a ball screw device that can facilitate mounting of a dust-proof member regardless of the thickness of a nut.SOLUTION: A ball screw device includes a screw shaft 10 and a nut 20 which is relative movably screwed to the screw shaft 10 through balls 30, and an engagement groove 22 is formed in a circumferential direction on an inner circumferential surface 20a of the nut 20 with a predetermined distance from the edge in an axial direction. The nut 20 is fitted with a cylindrical dust-proof member 40 for sealing the space between the screw shaft 10 and the nut 20. An outer circumferential surface 40a of the dust-proof member 40 is provided with a falling-off prevention engagement piece 41 that can engage with the engagement groove 22 of the nut 20, and a rotation prevention engagement piece 42 for preventing the rotation of the dust-proof member 40 fitted to the nut 20. |
