04979400 is referenced by 10 patents and cites 33 patents.

A safety belt assembly of the present invention measures the amount of force exerted on the assembly and also the point in time when a force was exerted on the assembly. The assembly includes a first and second member associated with one another, mechanism associated with the first and second members for resiliently restraining relative movement and movably retaining said members with respect to one another; a mechanism responsive to relative movement of the first and second members for enabing a measurement of force and indicating a point in time when a force was exerted on the assembly; and a mechanism for securing the assembly to a safety belt and/or a buckle or anchor. A chemical timer for measuring the elapsed time since a force was exerted on the assembly. The chemical timer includes micro-encapsulated reactants which are frangible in response to a force exerted on the assembly for beginning reaction of a time sensitive chemical reactive system which produces a measurable change over a predetermined time period.

Title
Force and elapsed time recording assembly
Application Number
7/316411
Publication Number
4979400
Application Date
February 27, 1989
Publication Date
December 25, 1990
Inventor
Donald D Bartholomew
Marine City
MI, US
Agent
Harness Dickey & Pierce
Assignee
Proprietary Technology
MI, US
IPC
G04F 7/00
G01D 21/02
G01D 1/12
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