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US 4,308,936 AGranted
Elevator system
AssigneeWestinghouse Electric Corp.
InventorsWilliam R. Caputo, John J. De Lorenzi
Life of this patent
Estimating the term…
Abstract
An elevator system including a comparator which develops a control signal responsive to the actual versus the designed performance of the elevator car as it approaches a floor at which it is to stop. This control signal is used in a monitoring and protective arrangement which controls pre-opening of the doors before the elevator car stops at a floor, as well as providing additional protection relative to the operation of the elevator car after it has made an inaccurate landing, and back-up protection for any movement of the elevator car with its doors open.
Claims8
An elevator system, comprising:
- a structure having a plurality of floors,
- an elevator car having at least one door,
- motive means for moving said elevator car relative to the structure to serve the floors,
- means defining a landing zone adjacent to each floor,
- means providing a speed signal responsive to the actual velocity of the elevator car, at least while the elevator car is in a landing zone, and in the process of stopping at the associated floor,
- means providing a first reference signal in said landing zone when the elevator car approaches a floor at which it is to stop, responsive to the designed approach velocity of the elevator car in said landing zone,
- means providing a difference signal responsive to any deviation between said speed and first reference signals,
- means providing a second reference signal,
- comparator means comparing said difference and second reference signals, and providing a predetermined output signal when the difference signal exceeds said second reference signal,
- and means initiating pre-opening of the door of said elevator car in said landing zone before the elevator car reaches the floor at which it is to stop, in the absence of said predetermined output signal.
7 more elements
Dependencies are inferred from the claim text.