| 摘要 |
PROBLEM TO BE SOLVED: To prevent a ball screw shaft from running out of the housing of a linearly working machine. SOLUTION: This linearly working machine has an output shaft threaded to a ball nut to be linearly moved forward and backward of an outer cylinder fixed to a housing 20 with the linearly reciprocal movement of the ball nut on a ball screw shaft 14 positively and negatively running with a driving motor. An on-axis disc 32 is fixed to the base end 24 of the ball screw shaft 14 and the first tension receiving rotor 36, a thrust bearing 45, the second tension receiving rotor 58 and a tension stopper 62 enlargedly mounted in an annular groove 60 are arranged on the ball nut side thereof. The second tension receiving rotor 58 is provided with a shrinkage preventive face 66 corresponding to the inner periphery of the C-shaped tension stopper 62 with a small gap. If tension and rotation are applied to the tension stopper 62 for shrinkage, the inner periphery contacts the shrinkage preventive face 66. |
