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US 4,434,874 AGranted
Elevator system
AssigneeWestinghouse Electric Corp.
InventorWilliam R. Caputo
Life of this patent
Estimating the term…
Abstract
A feedback controlled elevator system including a speed pattern generator for providing a speed pattern signal responsive to desired speed. A limiting signal responsive to the absolute position of the elevator car is compared with the speed pattern signal, and the lesser of these two signals is compared with a velocity signal to determine speed error.
Claims12
An elevator system, comprising:
- an elevator car,
- motive means for moving said elevator car in a predetermined travel path having upper and lower terminal zones and an intermediate zone,
- car position means providing a car position signal responsive to the absolute position of said elevator car, at least in the upper and lower terminal zones,
- means providing a reference signal responsive to said car position signal,
- speed pattern means providing a speed pattern signal indicative of the desired speed of said elevator car,
- limit means for providing a limiting signal responsive to said reference signal, at least when said elevator car is in one of said terminal zones,
- means having inputs responsive to said speed pattern signal and to said limiting signal for providing an auxiliary speed pattern signal which is responsive to the input signal of lesser magnitude at any instant,
- means providing a velocity signal responsive to the actual speed of said elevator car,
- and means for controlling said motive means in response to said velocity signal and said auxiliary speed pattern signal.
6 more elements
An elevator system, comprising:
- an elevator car,
- motive means for moving said elevator car in a predetermined travel path having upper and lower terminal zones and an intermediate zone,
- car position means providing a car position signal responsive to the absolute position of said elevator car in at least in the upper and lower terminal zones,
- first and second speed pattern means providing first and second speed pattern signals, respectively, at least in the upper and lower terminal zones, each indicative of the desired speed of said elevator car as it approaches the ends of the terminal zones,
- said second speed pattern means providing said second speed pattern signal in response to the car position signal provided by said car position means,
- means providing an auxiliary speed pattern signal in response to the lesser of said first and second speed pattern signals at any instant,
- means providing a velocity signal responsive to the actual speed of said elevator car,
- and means for controlling said motive means in response to said auxiliary speed pattern signal and said velocity signal.
5 more elements
Dependencies are inferred from the claim text.