GB485475A - Improvements relating to automatic gate-opening gear - Google Patents

Abstract

485,475. Door-operating apparatus ; fastenings. HASLAM, O. H. Nov. 24, 1936, No. 32212. [Classes 44 and 65 (i)] In automatic gate - operating apparatus of the kind in which a wheel of an approaching vehicle depresses a ramp or platform to open the gate through linkage or other connections, the vehicle holding the gate open by its weight until it has passed through, each ramp 8 has the end adjacent to the gate 3 pivotally supported at 11 and the other end connected to the gate-operating means and comprises members or teeth 21 projecting upwardly through a fixed grid or the like 22 which takes the weight of the vehicle when the ramp is depressed. The ramps are connected by a bridge-piece 4 extending under the gate and resting on the ramps at 24 to maintain the gate open during the passage of the vehicle ; the bridge-piece 4 may be constructed in the same way as the ramps, as shown, or may present a continuous surface and be depressed on to supports which take the weight of the vehicle. In the arrangement shown, a bracket 13 on the outer end of each ramp is supported by a three-armed crank 9 which is counterweighted to hold the ramp normally raised and is connected by a cable 16 to a wheel 25, this wheel being weighted to return it to its normal position after operation of the gate. A pin 30 on the wheel 25 engages a quadrant 31, which is freely pivoted on the axle of the wheel 25 and has a small counterweight 33 tending to move it anticlockwise, and a cable 32, adjustably attached to one end of the quadrant 31, runs round a quadrant guide 34 fixed to the gate 3 and is attached to a lever 35 pivoted to the quadrant 34. The lever 35 is connected by a link 44 and crank to a spring-returned latch-operating member, so that the first movement of the operating cables 16 releases the latch and the crank 35 then abuts against the quadrant 34 so that further movement opens the gate. The gate is closed by any weight or spring means when released, and is operable by hand independently of the mechanism. The latch may be dispensed with, the cable 32 then being attached to an arm on the gate or a lever which is pivoted on the gate-post to push against the gate or is otherwise connected to the gate.