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:
Feb. 25, 1992
Filed:
Sep. 28, 1990
David A Egbers, Arlington Heights, IL (US);
Steven D Jacob, Roselle, IL (US);
Landis & Gyr Powers, Inc., Buffalo Grove, IL (US);
Abstract
A sensing means for determining the absolute position of one or more structures such as doors, windows or the like that are moveable in sets of tracks. Apparatus comprises an electrical switching means having an elongated electrical resistance means with a predetermined resistance value per unit length located adjacent to one of the sash doors, actuator means associated with the sash doors for operating said switching means, circuit means adapted to provide a substantially constant electrical current through a portion of said resistance means between an end portion of said resistance means and the nearest switch location, said circuit means thereby providing a voltage signal having a magnitude that is proportional to the distance between said end portion of said resistance means and the switch location.