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:
May. 23, 2000
Filed:
Dec. 24, 1998
James W Fuller, Amston, CT (US);
United Technologies Corporation, Hartford, CT (US);
Abstract
A virtually active hitch system is provided for the damping of vertical oscillations of an elevator car during a semi-active hitch mode of operation along a relatively lengthy elevator travel path and for load leveling the elevator car during an active mode when the elevator is braked. The virtually active hitch stores energy derived from the elevator motor during the semi-active mode, and utilizes that stored energy during the active mode to actively adjust the positioning of the elevator car, as might result from load changes. The hitch assembly may advantageously use hydraulic piston and cylinder means to adjust, or impede adjustment of, a limited hitch gap between a support rope and the elevator car. The hydraulic circuit associated with the piston and cylinder may include a variable orifice valve to control damping action and a pair of accumulators controlled via a switching network to selectively store and release energy and to also serve as a spring.