| 摘要 |
A coarse machine screw which terminates in a gimlet point has a plurality of threads adjacent to the point end which have an included angle substantially greater than the standard included angle. In the preferred embodiment, two thread forms are employed, the thread form adjacent the point end having an included angle of about 90 DEG and the standard thread form, i.e. 60 DEG , comprising the balance of the threads. |
