GB976209A - Power operator for doors and the like - Google Patents

Abstract

976,209. Door and window operating appliances. STANLEY WORKS. Feb. 18, 1963 [Feb. 20, 1962], No. 6441/63. Heading E2M. A device for operating a closure member such as a door 12 slidable along a track 14 comprises an elongated collapsible conduit 18, means for selectively connecting one end of the conduit to a fluid pressure source and the other end to exhaust, and a closure actuator 40 secured to the closure member and having means such as rollers 62, 64 for clamping the conduit, whereby the actuator is moved along the conduit in response to a pressure differential therein. The actuator comprises a U-shaped bracket 46 secured by means of its lower limb 60 to a mounting bracket 42 so as to be adjustable towards and away from the door 12, the roller 62 being mounted in suitable bearings between the limbs 60 and the roller 64 being mounted between a pair of levers 66, 68 pivoted to the limbs at 70 and biased towards the roller 62 by springs 74. U-shaped guide members 76 for the conduit 18 are provided on the actuator. The ends of the conduit are attached to respective control units 20, 21 each of which includes an electromagnetically operated valve 22, 23 (Fig. 4) having a non-energized position connecting the conduit to exhaust and an energized position in which the conduit is supplied with compressed air from a pipe 29. A filter 30 and pressure regulator 34 are provided. The door is opened by closing a switch 130 which energizes the valve 22 and brings into operation a holding relay 138 for the valve solenoid 134. When the door reaches its open position it opens a limit switch 144 having normally closed contacts 145, thereby de-energizing the valve 22. Closing of the door is effected similarly by closing switch 132 to energize valve 23, the movement being arrested by a limit switch 142. Each control unit 20, 21 carries a shock absorber 90 adapted to bring the door gently to rest and comprising a damping piston 98 movable in a cylinder 92. The piston rod 100 is urged outwardly by a spring 116 and carries a rubber button 102 adapted to engage the side wall 52 of the mounting bracket 42 of the actuator. As the door approaches the end of its movement it drives the piston rod into the cylinder, the damping effect being controlled by adjustment of the valves 108, 110 through which air escapes from the cylinder. The piston rod carries a tubular rod 126 telescopically mounted on a guide rod 127, the end of the rod 126 being adapted to actuate the limit switch 142 or 144. In a modification (Fig. 8, not shown) the switch-actuating rod is not attached to the piston rod. An alternative control circuit is described (Fig. 9, not shown) which closes the door automatically when the fully open position is reached, time delay means being incorporated if desired. The switches 130, 132 may be of any desired type such as hand switches, mat switches or photo-electric cells. Screws 27 are provided in the couplings 24, 25 at either end of the conduit to restrict the flow and thereby vary the speed of operation.