在加工图1所示的零件中,要钻一个直径为0.4mm,角度为30°的锥形孔。刚开始时我们用ф0.4mm的中心钻进行钻削,加工中经常出现折断钻头的现象。后来,我们利用废铰刀或废旧小塞规,磨成与零件锥孔形状一样的尖头,并在尖头上开两条小槽(图2), In machining the part shown in Figure 1, drill a tapered hole with a diameter of 0.4 mm and an angle of 30 °. At the beginning we used ф0.4mm center drilling for drilling, processing often break the phenomenon of bit. Later, we use the waste reamer or a small plug gauges, ground into the same shape with the tapered part of the tip, and open two small grooves on the tip (Figure 2)