Patent ID: 6216824
Filing Date: 2001-04-17
Classification: B66B

Abstract:
A system for semi-active damping of oscillations during vertical motion of an elevator car position along an elevator travel path, the elevator car being connected by a rope to a sheave mounted to an elevator motor, the rope being connected to the car in a manner permitting limited relative vertical motion therebetween, the system comprising:means for providing a motion command signal which corresponds with an elevator travel profile dictated by a desired destination of the elevator along the elevator travel path;spring means effectively connected between the rope and the elevator car to provide a vertical spring force therebetween;controllable damping means effectively connected between the elevator car and the rope in parallel with the spring means, the damping means being responsive to a damping command signal for selectively impeding relative vertical displacement between the elevator car and the rope;means for measuring the vertical velocity of the elevator car and providing a signal indicative thereof; andcontrol means responsive to the motion command signal and to the car velocity signal for providing a damping command signal to the controllable damping means to selectively activate the controllable damping means.