Self-locking threaded plug

Abstract

A new plug is formed with a diametrical slot in the interior threaded end and an axial through hole. A spring unit is positioned in the through hole and slot. The spring unit is formed with a diametral slot that extends from the interior end of the plug well down into the post portion of the spring unit and therefore into the through hole. The spring unit is assembled to the plug prior to heat treatment of the spring unit. Fixturing of the spring unit determines the spring rate of the unit and, in combination with the fit of the spring unit in the slot and through hole, the amount of live contact of the unit with the threads of the hole into which the plug is to be threaded. The holding torque of the plug is thereby determined. The new plug eliminates the present need for external capture devices or stainless steel wires through holes in the plug exterior in aircraft applications.

Dependencies are inferred from the claim text.