| 摘要 |
PROBLEM TO BE SOLVED: To improve holding accuracy by providing a release cam with a level difference for attaching and detaching a half nut to/from a feed screw on a half nut release device linked with a slider release lever. SOLUTION: When the push button 4-1 of the release lever 4 of a slider 3 is pushed, a linking bar 7 is moved to left against a return spring 8. Thus, the release cam 9-2 of the half nut release device 9 fixed to the linking bar 7 is moved to the left as well and the low step part of the release cam 9-2 is abutted to the bearing 13-2 of the half nut 13. Thus, the half nut 13 is separated from the feed screw 12 by the force of a spring 11-1 and the slider 3 becomes freely movable. When the push button 4-1 is returned, the respective parts are reversely moved, the high step part of the release cam 9-2 is abutted to the bearing 13-2 of the half nut 13 and the half nut 13 is engaged with the feed screw 12. At the time, the half nut 13 is pressed in a direction vertical to the advancing direction of the feed screw 12 in a load state by the release cam 9-2 and floating is prevented. |
