Abstract: A device for automatically opening and closing a hinged door includes a motor having a drive shaft, a speed reducer, an operating shaft adapted to be connected to the hinged door and operatively coupled through the speed reducer to the drive shaft, a chain sprocket fixed to the operating shaft, a chain trained in mesh around the chain sprocket, a first rod having an end coupled to an end of the chain, with a first fixed to an opposite end of the first rod, a second rod having an end coupled to an opposite end of the chain, with a second flange fixed to an opposite end of the second rod, a first tubular body in which the first rod is axially movably disposed, a first spring disposed around the first rod within the first tubular body for normally urging the first flange in a direction away from the chain sprocket, a second tubular body in which the second rod is axially movably disposed, and a second spring disposed around the second rod within the second tubular body for normally urging the second flange in a

Abstract: A device for securing the locked position of a motor-vehicle door activated by a rotating post and that is locked or unlocked by raising and lowering the post has a disk attached to the post and a rotating support in the form of a double-armed lever mounted below the disk on a stationary section of the frame so that the support can be displaced into a position in which the disk rests on the top of one of the lever arms. The axis of rotation of the support is positioned on the frame section and lies in a plane that is perpendicular to the direction in which the rotating post is raised and lowered. The bottom of the second lever arm of the support rests on and is forced by a compression spring against a stop on the frame section and the bottom of the first arm of the support has a recess. A rotating locking element, which is also a double-armed lever with two support surfaces on one arm, engages the recess.

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 door operator for opening and closing doors on transit vehicles and the like includes an actuator (50) secured to the transit vehicle (10). The actuator houses a worm drive and a reciprocating air cylinder (52) for imparting rectilinear motion to the worm drive. A door shaft (18) is coupled to a door (14) and mechanically coupled to the worm drive such that rectilinear motion of the system is transmitted by the worm drive into rotary motion to the drive shaft to open and close the door. A cam (90) is secured to the vehicle and adjacent to a cam follower (108) that is secured to the door shaft. The cam follower engages the cam during approximately the initial 80% motion during closing of the door and approximately the final 80% of the door opening. A recycling switch (200) for the door may be mounted in the vehicle adjacent to the cam in a position to be engaged upon engagement of the door with an object to recycle the door.

Abstract: A piston and geared rack assembly are moved by pressurized air in opposite directions within a power cylinder housing as the vehicle operator registers door closing and opening commands in a solenoid valve. This lateral movement is converted to rotary movement by a pinion gear driven by the rack and coupled to turn a spindle shaft which drives the door. At full stroke during door closing, the power piston actuates a valve to charge the lower chamber of an auxiliary cylinder to move a lift piston rod, movable within the spindle shaft, to raise the closed door into a locked position. Upon a door-open command, the solenoid valve exhausts the charged cylinder chambers, admits air into the upper chamber of the auxiliary cylinder to move the lift piston and rod to lower and release the door, and slowly charges the associated opening chamber. This enables the delayed movement of the power piston and rack assembly in the opposite direction, reversing the rotation of the pinion and spindle shaft, to open the door.

Abstract: An automatic gate arrangement has a hollow and tubular lower post part defining an upright post axis and fixed to one side of the path, an upper end wall transverse to the post axis, and lower fasteners releasably securing the upper end wall to the lower post part. A support fixed to the upper end wall extends upward along the post axis therefrom and pivotally supports a gate shaft at the post axis. A reversible drive motor fixed on and underneath the upper end wall in the lower post part has a rotary output extending through the upper end wall. A transmission between the rotary output and the shaft converts rotation of the output into oscillation about the post axis of the shaft. A C-shaped gate projects laterally from the post axis and is secured to the shaft by connecting means for joint rotation about the post axis unless the gate and shaft are relatively rotated about the post axis with a force exceeding a predetermined maximum force.

Abstract: A traffic control arm powered by a motor and a linear actuator connected between the motor and the arm such that as the motor is rotated, a restraining force acting on the arm will not prevent continued rotation of the motor shaft.

Abstract: A self-operating damper device constructed to be installed in open ended furnace duct boots which terminate in room registers, said device operating in parallel with multiple units as part of a forced air heating and cooling system for the purpose of controlling and regulating the flow of the heating/cooling medium to individual rooms, independently and simultaneously through opening and closing of damper plate. Self-operating damper means include damper housing with rotatable damper plate hving an integral shaft with attached end pulley, said pulley being interconnected with motor means through drive belt which encircles both the damper pulley and motor pulley with drive motor being controlled by switch means operated by rotating cam on motor output shaft, said motor responding to commands of room thermostat which influences both motor means and combustion cycle of combustion means.

Abstract: Obstacle sensing apparatus for a pivotal door has a drive for operating the door between open and closed positions. Linkage is provided between the pivotal column which supports the door for swinging movement and a platform pivotally mounted on a fixed adjacent structure. When an obstacle is encountered the reactive force pivots the platform through the linkage and activates switches which reverse the drive. Elastic blocks keep the platform centered except when an obstacle is encountered.

Abstract: An apparatus for locking a door leaf comprising a turnable shaft secured to the door by an arm to drive the door in opening and closing movements under the action of a piston-drive which produces slight axial movement of the shaft as the door approaches the closed position. A first locking element is fixed to the door frame and a second locking element is fixed to the door, the locking elements having wedge-shaped noses which interengage and lock the locking elements when the door is closed and the shaft is lifted. The locking element on the door frame includes an axial extension overlapping the nose of the locking element on the door to form an abutment to limit the degree of angular closure of the door. The axial extension can carry a friction-reducing insert to facilitate relative movement between the noses when the door is lifted at the end of the closure movement.

Abstract: An automatic door closer providing for use as a light duty door opener and having a slip clutch for protecting the electric gear drive power unit from damage due to overspeeding on excess loads applied by overriding manual door operation. Zener diodes across the power supply to the electric drive motor effectively throw a heavy electrical load on the motor and cause the clutch to slip if the motor is sufficiently oversped and caused to act as a higher voltage bucking generator, as by manually forcing the door substantially faster in the direction in which it is being driven. A direct current motor is used at considerably lower than its rated voltage so that electrical power may be safely applied continuously for holding the door closed with the motor stalled, and without the clutch slipping, with the clutch set to slip only when the force applied thereto is significantly higher than the force required to stall the motor yet safe for the drive unit.

Abstract: A swinging door construction for a vehicle comprising a door panel having upper and lower swing arms coupled thereto and connected to a rotatable swing column. A drive mechanism is secured to the body of the vehicle and operatively engages the swing column to rotate the same and effect swinging of the door. The lower swing arm is connected to the swing column by a connecting member which extends upwardly above the drive mechanism and is secured to the swing column.

Abstract: The toll bar of a tollgate is pivotable between horizontal and vertical positions by a reversible electric motor through the medium of a swingable crank gear. A frame for the motor and crank gear is turnable on the shaft for the toll bar and causes a switch to open the motor circuit when the bar encounters excessive resistance to movement toward its horizontal position. The bar is detachably coupled to a holder and causes a switch to actuate an alarm device when it is detached from the holder in response to engagement by a vehicle which passes the tollgate while the bar is away from the vertical position.

Abstract: A remotely controlled gate opener for use with a pivotable fence gate is characterized by a closed loop drive chain which is mounted around a set of three triangularly positioned fixed sprockets including a motorized drive sprocket and two positioning sprockets. The gate opener is mounted adjacent the gate post supporting the gate and the gate is attached to the drive chain at a point between the positioning sprockets such that the drive chain, when propelled by the motor, acts to pivot the gate. The preferred embodiment includes a radio controlled motor controller for remote control of the gate opener.

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: Safety gate mechanism for use in protecting persons working around automobile service equipment installed in a floor pit comprising bi-parting gate sections mounted for movement between closed positions in front of the floor pit and open positions along side the floor pit, circuit means for automatically opening the gate sections once a signal is generated that a vehicle is to be placed in the floor pit area for service, and means in the circuit for locking and unlocking the gate sections and for reclosing the open gate sections in a desired time period should a vehicle fail to move into the floor pit area or after a vehicle has been removed from the floor pit area.

Abstract: An electrically powered drive system for automatically opening and/or closing the door of a motor vehicle. An electric drive assembly including a motor and an irreversible gear box is coupled to the hinge of the door by means of a normally-disengaged clutch. Control means are provided for selectively energizing the motor and clutch. In a preferred embodiment a solenoid is coupled to the system for unlatching the door preparatory to energization of the drive motor.

Abstract: A motor controller for use in railway-crossing signal-gate mechanisms is provided herein. The controller is of a cam type which includes a cam assembly having a movable cam insert that cooperates with a cam follower and switch assembly. The switch controls the gate arm raising motor. The cam insert and cam follower are arranged such that when the gate arm approaches the upright position the cam insert slides quickly or snaps to a position, which permits the switch contacts to open quickly, thereby minimizing arcing between the switch contacts. Moreover, with the cam insert in this position, oscillation of the gate arm about the upright position, which is caused by the gate arm striking the arm stops and bouncing back, is minimized.

Abstract: A door operator of electromechanical character for utilization with pivotally mounted doors, as by a center pivot, a butt hinge, or an offset pivot, comprising a prime mover, a driving shaft, adapted for rotation about a vertical axis and being secured through an arm to the door to be operated. A gear train interconnects said prime mover and said driving shaft wherein the gears are mounted as by a unique arrangement of needle roller and needle thrust bearings to permit said gear train to operate smoothly in door opening operation as a speed reducer and in door closing operation as a gear increaser. Energy storing means operatively connected to said driving shaft for storing energy during door opening operation and for energy releasing to drive said gear shaft during door closing operation. The said operator is adapted for compact disposition within the header of a door frame.

Abstract: A hydraulically controlled pneumatic swinging door operator comprising a pneumatic cylinder with a piston therein, a continuous loop connected to opposite sides of the piston and entrained at its ends over sprockets, one of which makes driving or driven connection with a door, a passive hydraulic system including a cylinder and a piston, the piston of which is carried by the side of the loop opposite the side carrying the pneumatic piston, and passage work in the hydraulic system for controlling the flow of hydraulic fluid in said cylinder from one side of the hydraulic piston to the other side.