图1所示的工件是在螺纹加工后再用成形刀推出50个“V”型槽。在推“V”型槽过程中,毛刺翻向螺纹中,故必须清丝。采用一般丝锥清丝,工效低、质量差,螺孔及丝锥螺纹不连续,丝锥与螺孔不易对正;丝锥稍有歪斜,不但难于达到清丝效果,而且还会破坏牙形。经多次试验,设计出如下两种结构的清牙丝锥,经使用,效果良好。图2所示的丝锥仅开有一个容屑槽,该容屑槽既短又浅(深于牙高即可)。丝锥整体上仍 The workpiece shown in Figure 1 was pushed 50 “V” slots with a forming knife after threading. In the push “V” groove process, burrs turned to the thread, it must be cleaned. The use of general silk taps, low efficiency, poor quality, screw and tap thread is not continuous, taps and screw holes is not easy to align; taps slightly skewed, not only difficult to achieve the effect of cleaning, but also to destroy the tooth shape. After many tests, designed the following two types of cleaning tooth tap, after use, the effect is good. The tap shown in Figure 2 has only one chip pocket open, which is short and shallow (deeper than the tooth height). Taps overall still