| 摘要 |
FIELD: machine building.SUBSTANCE: invention relates to the self-tapping screw, that is screwed in the non-threaded hole made in the blank, with formation of the internal thread in the hole. The self-tapping screw contains body, at that normal thread is made on the external peripheral surface of the body, at that multiple chip grooves are formed relatively to the circumferential direction of the normal thread by cutting out of the part of comb of the normal thread, and the engagement shoulder is provided on bottom of each chip groove along part or entire edge of bottom such that its continuously goes from the side surface of the normal thread.EFFECT: increased counteraction to loosening.3 cl, 11 dwg |
