Abstract: An elevator call box with internal, concealable latching mechanism comprises an internally disposed, cylindrical magnetic pin with a relatively low pull force that is slidably displaceable by an larger, external magnetic force supplied by a service technician. When the access door is closed, magnetic pin penetrates an orifice in a locking tab to lock the call box. The pin magnet is normally attracted to an adjacent, magnetically attractive clip snap-fitted to a latching block. The latch is externally disengaged via a stronger portable magnet carried by service personnel. The larger magnetic pull force of the portable magnet slidably displaces the smaller magnetic latch pin, freeing the locking tab to permit pivotal opening of the access door. Once the stronger magnet is moved away, the smaller magnetic pin, which is attracted magnetically to the clip, will return to it's rest position penetrating the locking tab and locking the control.

Abstract: An elevator call box with internal, concealable latching mechanism comprises an internally disposed, cylindrical magnetic pin with a relatively low pull force that is slidably displaceable by an larger, external magnetic force supplied by a service technician. When the access door is closed, magnetic pin penetrates an orifice in a locking tab to lock the call box. The pin magnet is normally attracted to an adjacent, magnetically attractive clip snap-fitted to a latching block. The latch is externally disengaged via a stronger portable magnet carried by service personnel. The larger magnetic pull force of the portable magnet slidably displaces the smaller magnetic latch pin, freeing the locking tab to permit pivotal opening of the access door. Once the stronger magnet is moved away, the smaller magnetic pin, which is attracted magnetically to the clip, will return to it's rest position penetrating the locking tab and locking the control.

Abstract: Modular elevator control housings having hinged faceplates that can be folded open to quickly expose the housing interior for service or modification. Each housing is generally in the form of a low profile, parallelepiped that is conveniently placed on a wall adjacent to an elevator car access position. The housing protectively encloses elevator operational controls, directional indicators, warning lights, or the like. The preferred housing comprises a chassis covered by a one-piece, folding faceplate interiorly hinged to the chassis that provides a display. The chassis comprises a subframe that secures the housing to the wall and a top and bottom cover. The subframe comprises a base bounded by integral, projecting side flanges that preferably terminate in upper lips. Extruded chassis sidewalls are secured to the subframe sides with fasteners captivated in part within captivating grooves defined in the sidewalls. Mounting grooves seat fasteners to secure the top and bottom covers to the sidewalls.

Abstract: A self correcting infrared intrusion detection system primarily for elevator doors establishes multiple through-beams to intelligently detect passengers and adjust for environmental changes. Beam patterns are monitored by software that differentiates between intrusions and malfunctions and adjusts itself automatically when hardware partially fails in the absence of an intrusion. The system automatically chooses and executes two different door-width sensing routines. A plurality of spaced apart transmitter stations mounted vertically apart in one door faces a plurality of spaced apart, receiver stations mounted in the other door. Each transmitter station periodically radiates modulated light towards the receivers in the opposite door. A main control circuit monitors all receivers, controls all the transmitters, and executes the software.

Abstract: A relative position derivation, sensing and indicator system primarily adapted for conventional elevators. The system displays elevator position and travel direction at each floor with a relatively old fashioned appearing indicator apparatus including an "antique" faceplate and a simple rotatable pointer arm driven by a stepper motor assembly. Electronic solid state digital circuitry is employed to derive suitable control signals for driving the associated stepper motors which rotate the pointer arms associated with each position displayed. A plurality of vanes vertically aligned within the hoistway are provided with parallel, offset rows of perforations. A generally U-shaped vane reader traveling with the elevator car establishes a pair of rapidly pulsed, oppositely directed infrared light beams across a void-like channel formed between its sides.

Abstract: A photosensor system includes a housing in which are defined a primary passage, and a secondary passage intersecting the primary passage at substantially a right angle. A light source is disposed in the secondary passage to direct light toward the intersection of the passages, and a beam splitter plate is disposed at the intersection at about a 45.degree. angle with the primary passage to direct light from the light source toward one end of the primary passage. Disposed in that end of the primary passage is a lens for collimating the light rays and directing them outwardly of the housing. One side of the beam splitter plate contains a reflective finish or surface to reflect light impinging thereon, and the plate includes an aperture therein for allowing the passage of light. When light directed outwardly by the lens encounters a retroreflector, some of the light is reflected back through the lens and through the aperture in the beam splitter plate toward the other end of the primary passage.