Helical spring fastener

USH1588H · kind H · statutory invention registration

Inventor

• David V. Arney · El Cajon, US

Key dates

• Grant date: Sep 3, 1996

Classification

• Technology area (CPC —): General

Abstract

The invention is a two-ended fastener having one end suitable for attaching the fastener to a base with a second end having a special thread that is substantially cylindrical at its root and sharp at its crown. This thread is designed to mate with the radially inward surfaces of a round wire helical spring so that the helical spring may simply be threaded to the fastener. By utilizing the special thread described, a high degree of surface contact between the fastener and the spring is made possible, increasing spring retention. The special thread inner diameter may be made slightly larger than the interior diameter of the spring so that the helical spring will be slightly expanded when threaded to the fastener. An elastic force between the threaded portion of the spring and the fastener further helps retain the spring to the fastener. This elastic force increases as an attempt is made to unthread the spring from the fastener.