SICH SELBST AUSRICHTENDES HOCHBELASTBARKEITSSCHRAUBSYSTEM

摘要

A fastener system includes a screw or bolt having two interleaved helical threads which bracket a helicoil. The helicoil expands and torques by various means to maintain hold and purchase between the screw coil combination and the substrate into which the screw and helicoil are inserted even when the substrate recedes a significant distance from the screw and helicoil combination. The two interleaved threads hold the coil and prevent it from rolling over the threads in high load applications.