型;S-7

The anti-triangle principle is adopted to increase the pull rod and at the same time the inside of the pull rod is provided with a rolling needle. When the external elastic force outside the swinging knife gear does not move, when it exceeds the force range, the rolling needle begins to work against the swinging knife gear external spring, and the rolling needle rotates in the opposite direction, which can not only withstand the swinging knife gear popping out, but also does not increase the current

This structure even if the big nut falls off will not appear the phenomenon of sliding teeth, which is the only one in the industry of non-sliding teeth scissors.