Abstract: A self-tapping, self-aligning thread repair insert is disclosed. The insert is an annular sleeve having a threaded interior surface, a partially threaded exterior surface, and an opening. The exterior surface has a tapered portion between a straight threaded portion and a straight thread-free portion. The thread-free portion and the opening are adjacent an end of the sleeve. The thread-free portion is free of threads for a distance of at least 1.5 thread widths from the end of the sleeve. The sleeve is made of a 400 series stainless steel. The sleeve is case hardened.
Type:
Grant
Filed:
September 8, 1986
Date of Patent:
March 15, 1988
Assignees:
David Diperstein, Groov-Pin Corporation
Abstract: The present invention relates to an improved method for economically manufacturing lobular internally and externally threaded self-tapping inserts. The method is characterized by the novel application of a conventional roll forming apparatus of the type including two cylindrical driven thread forming dies in combination with a specially configured lobular elongated stock material, resulting in the provision of a multiplicity of longitudinally spaced-apart, externally threaded increments which may thereafter sequentially be drilled, tapped and severed from the stock material.