Norman D Phillips

US Patent:

42046599, May 27, 1980

Filed:

Apr 25, 1978

Appl. No.:

5/899956

Inventors:

Norman S. Phillips - Dayton OH
William B. Walcott - Dayton OH

Assignee:

The United States of America as represented by the Secretary of the Navy - Washingtion DC

International Classification:

B60R 2110

US Classification:

248562

Abstract:

A notched-energy absorber for attenuating high level accelerations such as ould occur during aircraft crashes, thereby avoiding injury to a user. The energy absorber force-displacement curve has a large initial spike, followed by a valley or "notch" and then by a constant force level intermediate the spike and valley levels. In one embodiment, a conventional square-response type shock absorber is connected between a vehicle seat and the vehicle body by a shearable diaphragm fixed to vehicle structure. The diaphragm shears at a notch when it experiences an initial high force, after which the conventional absorber moves freely without deforming until it encounters a stop. The conventional absorber then elongates or compresses in a conventional manner. In an alternative embodiment, a spring is connected between the seat and the vehicle body. Initially, the spring is compressed by experienced forces until at a predetermined force level it forces out a retaining clip or ring.