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:
Apr. 08, 2008
Filed:
Nov. 16, 2004
Ralph C. Angiuli, Canfield, OH (US);
Michael T. Mcmahon, Salem, OH (US);
Brett A. Reed, Alliance, OH (US);
Ralph C. Angiuli, Canfield, OH (US);
Michael T. McMahon, Salem, OH (US);
Brett A. Reed, Alliance, OH (US);
Overhead Door Corporation, Farmers Branch, TX (US);
Abstract
An operator for a barrier, such as an upward acting door, includes a control unit having two optical limit switches providing output signals to a controller to effect shut-off of the operator motor when the door reaches open and closed limit positions. The limit switches preferably include LED emitter and phototransistor sensor elements and are preferably mounted on a circuit board in close proximity to a screw member which rotates in timed relation to the position of the door. Linearly movable nut members are mounted on the screw member and include or engage optical shield members which move into positions to provide respective output signals from the optical switches. The door closed optical limit switch may incorporate a pre-limit switch function to override a signal from a door bottom edge obstruction sensor.