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. 19, 1988
Filed:
Jul. 29, 1987
William R Caputo, Wyckoff, NJ (US);
Westinghouse Electric Corp., Pittsburgh, PA (US);
Abstract
A method and apparatus for providing a load compensation signal for the drive motor control loop of a traction elevator system which includes an elevator car having a load responsive platform and a counterweight. The load compensation signal transfers unbalanced torque from the system brake to the drive motor at the start of the run, to provide smooth starts. The load compensation signal is heavily filtered to provide a response time which will follow changes in car loading but too slow to affect car dynamics. Thus, the load compensation signal is continuously connected to the motor control loop, eliminating switches and memories, and enabling the compensation signal to directly aid car landing. Non-linearities in the load responsive platform are partially compensated for by three initial adjustments, and a fourth adjustment is provided for periodically offsetting changes due to ageing of platform isolation materials. The load compensation signal may be added directly to the motor control loop, or further processed to account for hoist cable weight compensation error at the location of the elevator car.