| 摘要 |
There is provided a ball screw device even with a small lead angle and a small number of circulation rolls, including a rotational part, which keeps unequal division of tongue portions and legs connected to the tongue portions to a minimum and ensures the strength of the tongue portions. A recirculating part 40 of the ball screw device thus includes a pair of legs 41, each having a tongue portion 44 for scooping up balls in a direction approximately tangential to a spiral raceway, and a main body 42 connecting the pair of legs 41. First divided faces A and C for dividing the pair of legs 41 along a ball recirculating path R, and a second divided face B for dividing the main body 42 along the ball recirculating path R are also included. The second divided face B is formed by an upper divided face B 1 and a lower divided face B 2 of the ball recirculating path R so that the upper divided face B 1 and the lower divided face B 2 intersect with each other when viewed from a flat surface 20a of the nut 20. |
