Abstract: A pulse generator is coupled to a car drive motor directly coupled to a sheave, over which a rope suspending an elevator car is passed, and the position of the car is calculated through the counting of pulses produced from the pulse generator. First and second car position detectors for detecting respective first and second car positions are provided within a hatchway, and the number of pulses produced during a period from the actuation of the first car position detector till the actuation of the second car position detector is detected. A count value for calculating the car position is corrected according to the difference between the detected pulse number and a reference pulse number corresponding to the distance between the first and second car position detectors, thereby effecting the compensation for the wear of the sheave and rope to improve the precision of the car position detection.

Abstract: An abnormal speed detector for an elevator system having an elevator car for servicing a plurality of floors, means for driving the elevator car in response to a speed command and a speed detector for detecting a running speed of the elevator car is disclosed. The abnormal speed detector comprises means for storing a set of speed data indicating a predetermined abnormal speed checking pattern as a function of running time or running distance of the elevator car, means for reading out of the storage means one of the set of speed data corresponding to an instant value of the running time or running position of the elevator car after the start of run, and means for comparing an actual speed of the elevator car with the readout speed data to determine if the speed of the elevator car is normal or not.