Self-locking bolt

Claim 1

A retractable self-locking bolt having a shank portion and a head portion, the end of said shank portion remote from said head being threaded to engage a threaded receptacle intended to be plugged by said bolt, a land extending radially from said shank intermediate said head and said threaded portion having a double faced cam portion each being axially spaced, a split ring cooperating with said double faced cam portion that engages the first face of said cam to position a portion of said split ring into an annular recess formed in said receptacle when the bolt is partly threaded in said receptacle, and engaging said other face of said cam portion when said head is seated into the locked position, said split ring being flexible and resilient to load said bolt in the locked position by said cam face so that a predetermined torque is required to overcome the force exerted by the split ring acting on said cam portion required to move said split ring off of said cam portion and an annular shoulder spaced from said land for preventing said split ring from sliding off of said shank and the diameter of said split ring being larger than the diameter of said shank so that it is loosely retained on said shank between said shoulder and said land.