GB481285A - Improvements in or relating to a mechanism for automatically opening and closing gates, doors and the like - Google Patents

Abstract

481,285. Rising hinges. CRAWFORD, R. B. (Crawford, N. S.) Aug. 8, 1936, No. 21897. [Class 65 (ii)] A device for automatic operation of gates and the like is adapted to complete the opening movement after the gate has been opened approximately half-way by hand or by contact with a vehicle and then to close the door completely. In the form shown in Fig. 2, the gate is fixed to a member 7 which is pivotally and slidably mounted on an upstanding part 4 of a fixed base 2 and which carries a roller 15 running on a curved track 5 on the base so formed that the gate is lifted on opening in either direction. On each side of the lowest point of the track 5 is a member 11 resting on the track and mounted by means of a pin running in a slot in a fixed bracket 6 on the base 2. When the gate is pushed open, the roller 15 moves up the inclined surface of the member 11, which then tilts under the weight of the gate so that the roller runs down the further side of the member 11 on to the track 5 and continues up the track 5 for a short distance to complete the opening of' the gate. The member 11 is weighted to return to its original position, and when the roller 15 runs down the track 5 as the gate closes under its own weight the roller engages under the upper end of the member 11 and lifts it so that it can pass underneath, the pin of the member sliding up the slot of the bracket 6. The mechanism is enclosed in a cylindrical wall 17, fixed to the base 2, which forms a lubricant reservoir ; a hood fixed to the member 7 fits closely over the wall 17. In another form, Fig. 7, the gate member 31, slidable and rotatable on the pivot 24, is formed with a bracket 43 carrying a roller 49 running on a fixed track 27 of similar form to the track 5 of Fig. 2 and also has a sliding block 50 which carries a roller 54 running on a fixed track 26. The track 26 is formed with a hump 26<1> on each side of its central point, and is bounded by a wall 28 having gaps 29, 30 through which the roller 54 can pass; the fixed pivot 24 has a spring-pressed plunger 60 which normally forces the block 50 out to the position shown against the action of tension springs 69. As the gate opens, the plunger 60 is forced back by the hollow pivot member 31, but the block 50 is prevented from following it by the wall 28 engaging the roller 54; the roller 54 therefore moves up the hump 26<1> and runs down the other side of the hump to complete the opening of the gate. The roller 54 can now be retracted through the gap 30 by the springs 69, and the roller 49 runs down the track 27 while the gate is closing under its own weight, the roller 54 being inside the wall 28, and thus clear of the hump 26<1>, until the closed position is reached, when it is projected through the gap 29 by the plunger 60. The closing movement may be assisted by a spring, surrounding a spindle fixed to the top of the member 24, pressing on a thrust bearing on the top of the gate member 31.