| 摘要 |
PURPOSE:To automatically and completely eliminate a backlash in cutting feed, by movably engaging a backlash elimination nut with a feed screw and bringing the nut into contact with a fixed nut to use them a combined nuts. CONSTITUTION:A backlash elimination nut 30 is movably engaged with a feed screw 1 behing a fixed nut 2. The feed screw 1 is fed in the direction of an arrow (a) by the rotation of the fixed nut 2 to perform cutting. The backlash elimination nut 30 is moved forth in the cutting feed direction together with the feed screw 1 so that the front end face of the nut 30 comes into contact with the rear end face of the fixed nut 2. As a result, both the nuts 2, 30 are furthermore moved forth by a quantity equal to the backlash between the nuts while their end faces slide on each other. When the backlash is almost eliminated, the nut 30 is locked up on the end face of the other nut 2 by the pressurired contact resistance. After that, both the nuts 2, 30 function as combined nuts to smoothly move the feed screw 1. |
