GB638812A - Improvements in and relating to folding and sliding doors - Google Patents

Abstract

638,812. Sliding doors. EDUCATIONAL SUPPLY ASSOCIATION, Ltd., and LEONARD, J. W. July 13, 1948, No. 18772. [Class 20 (iii)] A folding-sliding door of very large size, for example for an aircraft hanger, which comprises a number of columns supported at the bottom on a guide track and guided at the top between parallel guides, adjacent columns being hingedly connected to a pair of mutually hinged leaves which, when the door is extended, form a series of shallow Vees across the opening, is prevented from canting sideways in the plane of the door opening by two cables, stretched between anchorages near the top corners of the door frame and passing alternately under and over, a pair of pulleys mounted transversely on the top of each column, one cable of the pair passing over one pulley and the second cable passing under the other on each column. In the form shown, the door opening is closed by a number of separate door sections which are arranged serially along the guidetrack running lengthwise of the opening, each section consisting of end posts or " power mullions " 10, which contain driving motors (co-operating with cables) to propel the section individually along the guide track and to open and close the section, between which end posts slide columns 11. A pair of leaves 12, 13, hinged together at 15, are hingedly attached at 14 between each pair of adjacent columns I and between the end posts 10 and adjacent columns. At the top of each column and end post are mounted four long, vertical rollers 17 which engage between horizontal guides 18. Mounted transversely on each roller housing is a pair of freely and independently rotatable horizontal pulleys 23. A pair of cables 24 and 25, adjustably anchored at one end to a bracket 27 and resiliently anchored at the other to a bracket 26, pass under the pulleys 23a on the end post 10 and then alternately over and under pulleys 23 on the columns I the cables being arranged so that at each column one cable passes over one pulley 23, whilst the other cable passes under the other pulley of the pair. With this arrangement, the columns are free to move towards or away from each other, the cables counteracting the tendency, found in large doors of this type, for the columns to cant sideways, a tendency which is particularly apparent when the door is nearly collapsed.