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:
Aug. 09, 1983
Filed:
Oct. 08, 1981
Walter Kulischenko, Middlesex, NJ (US);
Philip E Bloomfield, Bala Cynwyd, PA (US);
Pennwalt Corporation, Philadelphia, PA (US);
Abstract
In a vehicle steering system for automobiles, for example, a steering column is provided with a rotatable flexible shaft at the end thereof for improving the ability of the column to absorb energy in a crash situation. The flexible shaft has at least one strip of a plastic material, preferably polyvinylidene fluoride film made piezoelectric by known methods, secured to an outermost winding of the flexible shaft. Turning the steering wheel will torsionally deflect the flexible shaft which causes the piezoelectric strips to generate millivoltages thereacross. A deteriorating flexible shaft will deflect more under torsional stress than a comparable newer flexible shaft and the piezoelectric strip or strips secured to the deteriorating shaft will consequently produce higher millivoltages. These millivoltages are amplified and fed to indicating means for indicating the degree of safeness of the flexible shaft.