04023213 is referenced by 89 patents and cites 4 patents.

A shock-absorbing system is provided for protective helmets such as football helmets or crash helmets which includes an impact-resistant shell, a plurality of webs secured to the inside of the shell in the crown portion, and a plurality of flexible plastic compartments containing foam secured to the webs, the compartments being interconnected by means of orifices of relatively small size and the interior of the compartments being at atmospheric pressure or slightly above.

Title
Shock-absorbing system for protective equipment
Application Number
5/686725
Publication Number
4023213
Application Date
May 17, 1976
Publication Date
May 17, 1977
Inventor
William Rovani
Chicago
IL, US
Agent
Hill Gross Simpson Van Santen Steadman Chiara & Simpson
Assignee
Pepsico
NY, US
IPC
A42B 3/02
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