Detection device having energy transmitters located at vertically spaced apart points along movable doors

• US 4,794,248 A
• Filed: 01/29/1988
• Issued: 12/27/1988
• Est. Priority Date: 07/16/1985
• Status: Expired

• Current Assignee: Otis Elevator Company (Otis Worldwide Corp.)
• Original Assignee: Otis Elevator Company (Otis Worldwide Corp.)
• Inventors: Gray, John E.
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Oen, William L.
• Application Number:
  US07/148,203
• Time in Patent Office: 333 Days
• Field of Search: 250/221, 250/222.1, 340/21, 340/19 R, 340/545, 340/555, 340/557, 340/556, 49/25-28, 187/51, 187/56
• US Class Current: 250/221
• CPC Class Codes: B66B 13/08 guided for horizontal movement
• CPC Class Codes: B66B 13/26 between closing doors
• CPC Class Codes: E05Y 2900/132 Doors
• CPC Class Codes: G01V 8/20 using multiple transmitters or receivers

Abstract

In the entranceway between an elevator car and a floor are two oppositely sliding doors. The approach of these doors is controlled by a detection system that senses the presence of objects between the doors. This system includes, on each door, a plurality of emitters which are vertically spaced apart the door edge, for radiating noncollimated light towards the edge of the other door. At the top and bottom portions of each door edge there is a sensor which can receive the radiation from the emitters on the other door edge. The emitters on each door edge are sequentially turned on and the sensors on the opposite door edge provide a corresponding signal as they are turned on, unless an obstruction is in the way, causing the detection system to generate a signal that thus indicates that an object is between the doors.

Claims

1. A method for detecting the presence of an object in the path of a closing sliding door, characterized by:

sequentially activating energy transmitters as the door closes, to transmit energy between vertically spaced apart points along one of the two vertical edges of the area closed by the door to a detector on the second of said edges, an imaginary line between the detector and each transmitter decreasing as the door closes and being at an angle greater than 0 but less than 90 degrees to the direction in which the door slides;

sensing the transmitted energy with the detector for producing an output signal in response to the energy;

sensing the output from the detector when the energy is transmitted from each energy transmitter and providing a door stop signal when there is no output from the detector when each energy transmitter is activated.

2. A detection system for detecting the presence of an object in the path of a closing sliding door, characterized by:

a plurality of energy transmitters located at vertically spaced apart points on one vertical edge of the area into which the door slides to a closed position;

a second vertical edge on said area that is substantially parallel to said one edge, the distance between said one edge and said second edge decreasing as the door closes;

an energy detector capable of providing an output signal in response to the energy transmitted by each transmitter, and is located on said second vertical edge at a position at which an imaginary straight line between the detector and each transmitter is at an angle greater than 0 but less than 90 degrees to an imaginary line defining the direction in which the door slides;

means for activating the transmitters sequentially as the door closes;

means for providing a door control signal when a transmitter is activated and an output signal is not produced by the detector each energy emitter and energy detector having relative motion towards each other as the door closes.