| 摘要 |
<p>PURPOSE: A chip-resistant cutting tap is provided to solve the problem of the tap which is chipping when the tap is separated from a hole by forming a gap between a maximum chamfer relief angle point and the land. CONSTITUTION: A chip-resistant cutting tap (10) includes a body (12) comprising an axial front end unit (14) and an axial rear end unit (16). The body comprises a screw thread body unit (20) having spiral grooves which is adjacent to the axial front end unit, a cylindrical shank unit which is adjacent to the axial rear end unit, and a longitudinal central axis. A chamfer relief is extended from a cutting edge to the hill of the land in a radius direction. The amount of the chamfer relief is proportional to the angle measured from the cutting edge. The chamfer relief is extended to a gap between a maximum chamfer relief angle point and the hill and forms a gap which is smaller than the maximum value of the chamfer relief oriented towards the outside in a radius direction.</p> |
