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:
Oct. 25, 1988
Filed:
Dec. 09, 1985
Jack Abrams, Northbrook, IL (US);
Michael A Wisniewski, Bolingbrook, IL (US);
Bell & Howell Company, Skokie, IL (US);
Abstract
A novel spring and dual pulley construction wherein the pulley includes a pair of co-axial grooves, one of the grooves having a constant diameter that accepts a powered cable acting in one direction, while the other groove has a varying radius of curvature that accepts a second cable connected to one end of the tension spring and with the other end of the spring fixedly mounted. This arrangement maintains a constant spring force on a member moving along a slide in a reciprocating fashion and having one side thereof connected to said powered cable for movement in one direction and the other side connected to the second cable for movement in the opposite direction activated by a constant spring force regardless of the extension of the spring.