| 摘要 |
The anti-loosen self-tapping screw includes a head, rod and a thread. The rod extends from the head and an end of the rod forms a conic tapping tip. The thread is around the rod from the tapping tip to a position near the head. The thread is provided with an axial groove to cut off the thread. The divided ends along one side of the groove are separately provided with expanded portions whose cross-sections are expanded. |
