GB481990A - Improvements in and relating to controlling means for doors and the like - Google Patents

Abstract

481,990. Door - operating apparatus. WAYGOOD-OTIS, Ltd., and IRWIN, E. G. Nov. 24, 1936, No. 32112. [Class 65 (i)] The two leaves of double swing doors are interconnected to move in unison by a linkage including a pair, of elements which have a separating movement when the doors are opened and which are interconnected or acted on by restoring means opposing their separating movement and thus tending to close the doors. In the arrangement shown, each door pivot 2 carries a cam member 8 round which passes a section of chain 22 attached to the member 8 at one point. Slidably mounted on the frame between the doors are two bars 14, 15 having at their ends lugs 19, 20 and 17, 18 respectively, one of the chain sections being connected to the lugs 18, 19 and the other to the lugs 17, 20. A cylinder 23 pivoted to the lug 17 and sliding between rollers 35 has its piston connected to the lug 19, and contains a compression spring acting on the piston to oppose separation of the lugs 17, 19 by the opening of the doors ; the leverage of the spring is reduced as its stress increases by the effect of the cam members 8. The cylinder has an air-leak valve 32 at its inner end to give a checking action in the closing movement, and its wall is grooved to byepass the piston as it approaches the closed position ; preferably, one tapered groove and a shorter rectangular groove are provided. The position of the piston in relation to the grooves in the closed position is varied by adjusting the attachments of the chain sections 22 to the bars 14, 15. An additional connection between the doors is provided by an adjustable link 13 attached to crank pins 12 on extensions of the members 8. The doors may be held open by spring-pressed balls in the housings of the pivots 2 engaging recesses in the members 8. Instead of the restoring device 23 interconnecting the separating parts of the linkage, separate restoring means, which may be weight-operated instead of resilient, may be arranged to act on the linkage parts.