Abstract: A device. The device includes a shaft having a longitudinal axis, a first end, and a second end. The device also includes a connector attached to the first end of the shaft. The device also includes a rod connected to the shaft. The rod comprises a third end and a fourth end. The third end is connected to the second end of the shaft. The rod is about parallel to the longitudinal axis. The device also includes a spring surrounding the rod. The spring is compressible or extendable along the longitudinal axis. The device also includes a stop connected to the rod at a position distal to the spring. The stop resists longitudinal compression or extension of the spring.

Abstract: A gear assembly comprises a housing, a first gear shaft in the housing, a first spiral gear coupled to the first gear shaft in the housing, a second gear shaft in the housing, a second spiral gear coupled to the second gear shaft in the housing, and a fluid connection between a first chamber and a second chamber. The first spiral gear and the second spiral gear couple to define the first chamber and the second chamber within the housing.

Abstract: An arrangement and a method for monitoring the operational condition of an automatic door in an elevator, particularly a passenger and/or goods elevator, or in a building, the arrangement includes an automatic door which includes one or more door leaves, which slide horizontally in their location, a door operator, which includes a door motor and a door mechanism for moving the door leaf horizontally in its location, a closing device for closing the automatic door, a control system for the door operator for controlling the door motor, a device configured to define the operational condition of the closing device and the door mechanism of the automatic door, the device configured to define the operational condition of the closing device and the door mechanism of the automatic door includes a mechanism configured to determine the mechanical energy of the shaft in the door motor of the automatic door during an operating cycle.

Abstract: A control mat monitoring and warning apparatus and method in which the resistance of a control mat is monitored continuously while the mat remains in use. Deviations of the pattern of control mat resistance values in use from a nominal range of acceptable values is used to detect and report deterioration of the electrical performance characteristics of the control mat so that the mat can be removed from service and replaced in a timely manner. The disclosed invention also generates proper presence detection signals by compensating for the deteriorating electrical performance characteristics of the control mat, thereby extending the useful functional life of the control mat beyond the point at which the mat could otherwise function properly.

Abstract: A mat monitor for an automatic swing door system is mountable in-line with an approach mat and a safety mat and the controller for the automatic door system. The monitor emits a visible light to indicate that a mat is properly operating without requiring that the door cycle through an opening/closing sequence. In one embodiment, a green light is illuminated to indicate that the approach mat is properly functioning and a red light is illuminated to indicate that a safety mat is properly functioning. The mat monitor is preferably mounted at the underside of the header adjacent to the controller.

Abstract: An electrically powered pet door assembly for use in a home or building. Each assembly includes a frame which is secured to an exterior surface of a building, a panel slidably mounted within parallel tracks of the frame, a rotatable and translational drive assembly for vertically raising the panel, a centrifugal brake for controlling the speed of the vertical opening or closing of the panel and a treadle for activating the rotational and translational drive assembly.

Abstract: This invention relates to an apparatus for opening and closing a rear door of a vehicle such as a dump truck. The rear door of the vehicle is bisected into left and right rear door sections. When opened, the bisected left and right rear door sections are moved toward the outsides of the both side walls of the bed of the vehicle by the power of a drive cylinder provided on the lower surface of the floor of the bed of the vehicle, respectively. When the operating rod of the drive cylinder is extended, each of the left and right rear door sections is moved through a single or a plurality of links. Arcuate portions are preferably formed on the inner wall surfaces on the sides of respective out side end portions of the left and right rear door sections so that the door sections, when being opened, can be smoothly moved around the rear edges of said side walls to positions outside the side wall.

Abstract: A lock for a sliding panel such as a sliding glass door includes a chain which bends in only one direction. The chain, when latched, forms an incompressible column between the openward edge of the panel and the door frame. Unlatching allows the chain to bend in its allowed direction and fall vertically along side the door frame, thus allowing the panel to open.

Abstract: An automatic door installation with two traffic sensors mounted on each side of the door adjacent the opposite side edges thereof, each having a reflected energy receiver and a plurality of radiant energy emitters with angularly spaced beam axes to provide broad coverage areas intersecting the traffic path of travel. The emitters of each sensor are selectively activated at different radiant energy levels and/or selectively deactivated to vary the effective coverage area as the door is swung between its closed and open positions.

Abstract: In a door opening and closing apparatus a reversible drive motor and door actuator are mounted in the framing above a door header. The vertically disposed drive shaft of the motor is connected with the door actuator through a friction clutch equipped drive train including a series of speed reducing torque increasing cog belts and pulleys. The drive train operates pivoting linkage secured at one end to the door for biasing the door open or closed in response to the direction of rotation of the drive motor. A circuit connects a source of electrical energy with the drive motor through a plurality of current switching relays also inducing magnetic flux in the field windings of a braking slave motor driven by the driving motor. Door opening action is initiated by a foot pressure switch.

Abstract: An automatic mat-activated operating system for swinging doors provides approach circuitry for opening the doors when an approach mat at the entrance side of the doorway is activated and override safety circuitry for stopping door opening movement and returning the doors to a closed position when a safety mat at the exit side of the doorway is activated within a predetermined initial range of door movement but not thereafter and also for preventing door opening movement if the safety mat is already activated at the time of initial activation of the approach mat. The control system thus protects pedestrians at the exit side of the doorway from being struck by the doors during their initial opening movement which may not be readily recognizable and avoidable and also protects pedestrians entering the doorway from the entrance side from being struck by unexpected return movement of the doors.

Abstract: A pedal actuated laterally swinging gate comprises the gate, a wheel-engaged pedal mechanism at each side of the closed gate for causing the gate to open in the direction away from an approaching vehicle, and a fence-like board barrier to guide vehicles to the pedals, to protect the pedal mechanisms from livestock and to support the unit which flings the gate open, leaving the gate easy to open manually and permitting the gate to be an easily swung structure.

Abstract: An automatic door installation with four traffic sensors mounted on the door jambs on opposite sides of the doorway opening and having radiant energy emitters and reflected energy receivers for sensing doorway traffic. Two sensors are employed to cover the exit or swing side of the doorway, a threshold sensor is employed to cover the threshold area and an entrance sensor is employed to cover the entrance side of the doorway. The entrance and two exit sensors each have a plurality of radiant energy emitters with angularly spaced beam axes to provide broad coverage areas intersecting the traffic path of travel. The emitters of the exit and threshold sensors are selectively deactivated as the door is swung between its open and closed positions to avoid sensing the door. The emitters of all four sensors are pulsed in a predetermined sequence and the sensor receivers are timely activated to receive reflected radiant energy from the respective emitter(s) only.

Abstract: An automatic door operator for a swing door supported by a door supporting frame to swing about a vertical axis. The automatic door operator includes a mechanism for opening and closing the swing door, a drive for driving the door opening and closing mechanism to open the swing door, the drive including a prime mover for driving the door opening and closing mechanism, a door closer including a resilient device for storing part of mechanical energy provided by the drive in opening the swing door and for exerting driving force on the door opening and closing means by using the stored mechanical energy to close the door, a unit for electrically controlling the drive to swing the swing door, and a sensor for sensing a body accessing the door and thereby providing an electric signal to open the door to the controlling unit.

Abstract: A monitor for an electrically-controlled system is provided. A threshold detector senses the voltage variations in the system by means of an optocoupler. The system is disabled by a relay if a voltage level does not meet a predetermined parameter.

Abstract: A pressure sensing mat utilizes a thin sheet of semiconductor material that has an electrical conductivity generally invariable as to pressure applied to the mat material. The sheet of semiconductor material is sandwiched between sheets of copper, steel or aluminum foil which are in mechanical contact with the semiconductor sheet to define a pair of electrodes. The electrodes are connected to various circuits including a pressure (voltage) threshold detector, a learning circuit for establishing a learned threshold, a circuit for matching time-pressure patterns and a circuit for detecting pressures between a predetermined maximum and minimum level. A matrix of pressure sensing mats is utilized with various circuits to detect sequential pressure patterns.

Abstract: This invention is related to an automatically opening door for pets, mounted in an opening of a building without requiring changes to the opening structure.

Abstract: A door operator with a reciprocable rack gear adapted to be actuated in opposite directions by an electric motor driven screw and a coaxial helical compression spring for rotating a drive gear of a door operating spindle in opposite directions for opening and closing a swinging door, the rack gear forming part of a spindle operator having lateral bearings engageable with the ends of the spindle and adapted to be mounted in either of two 180.degree. angularly spaced positions about the axis of the drive screw for rotating the spindle in opposite directions, and the coaxial compression spring being operable via the rack gear for biasing the spindle in both directions to an intermediate position thereof.

Abstract: In a safety mechanism for highway exit ramp, dual motions are provided in the structural operation of the mechanism wherein a warning member, such as a length of barrier or semaphore, is pivotally mounted between an upright position and into a horizontal and cautioning disposition across the roadway, but in addition, the warning member itself is horizontally pivotal in the event that a moving vehicle should strike the same. The mechanism includes a detection member, such as either a protruding device capable of being pivoted by the vehicle passing thereover, or an electronic detecting device as provided in the roadbed of the ramp and when encountered by a vehicle travelling in the wrong direction disengages a detent that releases a spring mounted rack that turns its pinion for pivoting the warning device across the roadway.

Abstract: A train tunnel is ventilated by closing an exit end of the tunnel as a train approaches the entrance end, so that during passage through the tunnel the train acts as a loose piston moving through a long closed cylinder, to cause a rapid airflow rearwardly around the train.

Abstract: An automatic sliding door operator for a door mounted upon a door frame for sliding movement in a vertical plane between opened and closed positions includes a drive cylinder to open and close the door by means of a drive piston slideably movable within the drive cylinder between fluid inlets located at each end of the cylinder. Control means are provided to couple a first fluid inlet of the drive cylinder through a controlled source of fluid pressure and to exhaust the opposite fluid inlet continuously throughout an opening stroke of the door and for connecting the second fluid inlet to the source of fluid pressure and exhausting the first fluid inlet continuously throughout a closing stroke of the door. The closing and opening rates of the door is controlled by suitable exhaust metering means continuously metering the exhaust flow of fluid.