Elevator floor leveling system

Abstract

Abstract A system for landing and leveling elevators or otherwise controlling the spacial relationship between two relatively movable objects. The system incorporates a pair of vanes that include a light transmitting opening along their long dimension. A light bulb movable with the elevator car traverses the space between the two light vanes and a pair of light sensors view the light bulb through the openings in the vanes. The vane openings are tapered from a relatively large to a relatively narrow end and this taper is in opposite directions on opposite ones of the pair of vanes. The relative displacement position between the light vane and the sensor-bulb position, that produces an equal signal on each sensor, comprises a null, and this null position is set to correspond to the desired location for the car. The null is developed by comparing the signals in a differential amplifier, any deviation from the null position will produce an amplified error signal that may be used to input an electronic elevator drive control means or other means for controlling relative motion. Also incorporated in the system is an error modifying means for increasing the error signal when there is a relative acceleration between the parts of the system. The signal is also increased and at an increasing rate with the persistence of an error for a period of time. Thus, the system closely follows the movement of the elevator with respect to the hoistway and maintains its position accurately at the desired floor level through inputs to the elevator drive means.

Inventors

• 👤 W Hoelscher

Bibliographic Details