The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 30, 2002
Filed:
Jul. 30, 1998
James Scott Ewing, Chevy Chase, MD (US);
Maria Maroulis, Bowie, MD (US);
Andrew F. Conn, Baltimore, MD (US);
Cerebrix, Chevy Chase, MD (US);
Abstract
A helmet is formed with a rigid outer shell and three energy-absorbing layers made of two types of CONFOR™ ergonomic, open-celled polyurethane foams. The first layer adjacent the rigid outer shell is a CONFOR™ CF-40 yellow foam and the middle layer is a CF-47 green foam, which is of greater stiffness than the outer layer. The inner-most layer is also a CF-40 yellow foam and, therefore, identical to the outer energy-absorbing layer. The three layers are 0.5″ thick. The helmet body is secured to a user's head with straps, affording a helmet design capable of continuously absorbing energy from multiple impacts while retaining the property of returning completely to its original shape. The multiple layering of materials having different stiffnesses results in the reflection of propagating stress waves through the materials, ultimately absorbing larger amounts of energy than the same materials not layered with alternating stiffnesses could absorb.