GB1056615A - Power operated door opener - Google Patents

Abstract

1,056,615. Door operating mechanisms; doorchecks. RONAN & KUNZL, Inc. July 29, 1964 No. 30159/64. Heading E2M. A power operated door opener fitting within a thin header or threshold chamber and operated for example by a mat switch comprises a hydraulic piston 48 and cylinder 22 which move a cam plate 34 having a slot 37 engaging a roller 40 mounted between superposed crank arms 39, the door pivoting about the crank 29. Springs 23 are compressed when the door is opened and assist the closing action. A supply conduit 16 and return conduit 17 connect the cylinder to a pump. In the open position the crank 29 abuts a stop 45 having an aperture 46 to form a resilient abutment. Initial opening of the door is rapid and an adjustable needle valve (75 Fig. 8, not shown) determines the final speed of opening. Pressure is maintained to hold the door open against the stop 45. When the door closes, oil in the inner end (the right hand end in Fig. 3) of the cylinder 22 escapes through a hollow needle valve 96 slidable in a bore against the pressure of a spring. Further valve means ensures that the closing movement is checked. (Valve 104 Fig. 16 not shown constitutes a door closing speed control valve). The springs 23 finally give a positive closing motion, for emergency operation, the door may be pushed open in the opposite direction when the roller 40 presses on a nose portion 38 of the cam plate 34 and moves the plate slightly to the right in Fig. 3 the arm 39 is then free to swing the roller in the cam opening 35. An inclined edge 120 on the cam plate 34 presses against the roller 40 in the door closed position to prevent rattle or opening due to wind pressure. The device may be applied to multiple doors.