我们看到本列1975年11期介绍的“车床拖板钻孔夹具”一文,印按介绍的方法作了改装,一试效果确实很好,钻孔实现了自动走刀,再也不用手摇了,但是同时我们又发现还存在一些问题:①每次中拖板要对准原来的刻线,一是时间长容易忘了,二是对准中心时有误差,不能进行镗孔等精加工。②此夹具装夹在刀架上,刀架位置被占用,刀具的安装位置少了,换刀多的工序加工中很不方便。针对上述问题,我们进一步作了改进:(见插图)在大拖板 We saw this column introduced in 1975, 11 “lathe drag plate drilling fixture,” a printed version of the method introduced by the modified, a really good result, drill to achieve an automatic knife, no longer need to hand crank However, at the same time, we also found that there are still some problems: ① each time dragging the board to align the original engraved line, one is easy to forget for a long time, the second is the center of error, can not be boring and other finishing . ② The fixture is mounted on the tool holder, the tool holder position is occupied, the installation position of the tool is less, and the tool changing process is very inconvenient. In response to the above issues, we made further improvements: (see illustration) in the big drag