Patent Number: 6,167,991

Title: Method and apparatus for detecting position of an elevator door

Abstract: A method and apparatus for detecting the distance between opposing sides of an elevator door system is presented. The invention enhances the ability of an elevator door safety system to discriminate between false targets and true obstructions. The method detects distance between a first plurality of emitters and a first plurality of receivers mounted on the opposing sides of the elevator door system. The method comprises emitting an energy beam from an emitter. A halo component of the energy beam, having a predetermined wide angle, is sampled with the plurality of receivers to provide a set of energy signals indicative of intensity of the halo component energy sampled. From the set of energy signals, a vertical distance from the center of the pattern to an intersection of the halo component with the first plurality of receivers is determined. The distance between the first plurality of emitters and receivers is then calculated utilizing the predetermined wide angle and the vertical distance.

Inventors: Full; Gary (Tucson, AZ), Pustelniak; Richard (Tucson, AZ)

Assignee: Otis Elevator Company

International Classification: B66B 13/26 (20060101); B66B 13/24 (20060101); G01V 8/20 (20060101); G01V 8/10 (20060101); E05F 15/00 (20060101); B66B 013/26 ()

Expiration Date: 01/02/2018