Abstract: An edge device for an elevator door includes an elongate array of infrared transmitters and/or receivers and a proximate elongate array of illuminable elements, both arrays extending for a substantial part of the length of the door. The illuminable elements are adapted to be illuminated when the door is in motion. The two arrays are disposed in a common carrier structure, being either vertically interleaved or extending vertically in parallel with each other.

Abstract: A safety sensing system includes an apparatus for use in a doorway having a powered door slidable for closure of the doorway. The apparatus includes radiation transmitters and/or receivers for providing a curtain of detection beams across the doorway, and is formed as a composite structure that includes: a fixative member connectable by securing means to a side of the doorway at a door frame, the fixative member including a first portion of a mating connection means; and, a housing containing a plurality of the transmitters and/or receivers along its length, and including a second portion of the mating connection means for attaching the sealed housing to the fixative member. The mating connection means allows the housing to be removed and replaced while the fixative member remains in situ.

Abstract: A safety sensing system includes an apparatus for use in a doorway having a powered door slidable for closure of the doorway. The apparatus includes radiation transmitters and/or receivers for providing a curtain of detection beams across the doorway, and is formed as a composite structure that includes: a fixative member connectable by securing means to a side of the doorway at a door frame, the fixative member including a first portion of a mating connection means; and, a housing containing a plurality of the transmitters and/or receivers along its length, and including a second portion of the mating connection means for attaching the sealed housing to the fixative member The mating connection means allows the housing to be removed and replaced while the fixative member remains in situ.

Abstract: A elevator door protection system, having an infrared curtain comprising pairs of infrared transmitters and receivers and circuitry responsive to an output of the receiver due to interception for opening the elevator doors, includes detection circuitry which responds (a) when the elevator doors are closed, so as to reduce the usual power supplied to the transmitters; and (b) when the elevator doors open, so as to restore the usual power to the transmitters. Preferably, a time delay is included so that power dissipation is reduced only after a predetermined period following door closure. The invention reduces power consumption of infrared transmitter diodes, hence extending their lifetime.

Abstract: In a lift installation in which a multi-beam curtain (primary beam) extends across a lift car door opening, auxiliary transmitters direct secondary beams towards a detection zone in front of landing doors. The multi-beam curtain is intercepted by a passenger entering the lift to prevent premature door closure. However, premature closure is also prevented when a passenger stands in front of the landing doors, thereby causing some of the secondary beam to be reflected onto auxiliary receivers. This provides a low cost solution to the problem of non-detection of an obstruction in the closing path of the landing doors, but not intercepting the primary beam system and also provides an increase in the passenger convenience of the lift, as the doors are held open for a passenger approaching the lift, but not yet interrupting the primary beams.

Abstract: A laser light emitting diode (1, 2) situated at a focal point of a specially shaped lens (3, 4) produces a very thin intense fan-shaped beam. One or two such laser light transmitters are used to radiate a fan-shaped beam which is intercepted by a person or object thereby scattering laser light, by diffuse reflection. A cylindrical lens (5) receives a reflected component and this is detected by sensors (6) which are connected to circuitry including a synchronous detector (12) and comparator network (13, 14). The synchronous detector (12) is driven by a square wave oscillator (8) which modulates the laser light.

Abstract: Apparatus for controlling a lift door in which a detection zone (10) is illuminated with an infrared light source (15) and reflected light is received by image sensing device (18). A data processing device (17) is programmed to analyse video information stored in a video memory (22) and a reference field memory (23) so as to distinguish an object approaching the lift doors (1, 2) from an object passing by the lift, and also distinguishes stationary objects in the path of the lift doors (1, 2) from background objects. In a preferred embodiment, a low resolution image sensing device (18) is used and video information is binned and stored in the video memory (22).