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:
Nov. 28, 1989
Filed:
Jul. 11, 1988
Thomas J Davis, Warren, OH (US);
Other;
Abstract
Counterbalancing mechanism for a garage door or other device in which a torsion spring end member is fastened to a second member to which it is connected during normal operation of the counterbalance by cooperating interfitting elements on the members which allow longitudinal movement of the end of the spring during a spring adjusting operation. The counterbalance hardware includes a self-locking winding mechanism for winding or unwinding one or more torsion springs which operates to fix one end of the spring connected thereto against movement during normal operation of the counterbalance. The structure connecting the ends of each torsion spring into the hardware is such that each end of the spring is always connected for rotation with either the torsion shaft of the counterbalance or the self-locking mechanism including during the adjustment or setting of the torsion in the springs. The mechanism is used in a novel method of setting or adjusting torsion spring tension in which the door is initially in a down position with the door unlocked and springs unwound. The springs are then wound to initially partly fit the door and then unwound to seat the door to establish the proper tension in the springs. Two springs are connected to the winding mechanism and are adjusted simultaneously.