| 摘要 |
A ball screw device 1 has a screw shaft assembly 15, a nut 7 having an inner diameter smaller than the outer diameter of the screw shaft assembly 15 and formed in a tubular shape, and balls 9 rolling on helical raceway grooves 3, 8 formed in the outer peripheral surface of the screw shaft assembly 15 and the inner peripheral surface of the nut 7. The screw shaft assembly 15 has a first screw shaft 16, a second screw shaft 17 having a shaft raceway groove 3 with the lead same as the lead of a shaft raceway groove 3 formed in the first screw shaft 16, and a screw-in spacer 11 having the inner peripheral surface fitted on shaft sections 18, 19 each formed on one end of each of the first and the second screw shafts 16, 17. |
