GB749539A - Improvements in or relating to folding doors - Google Patents

Abstract

749,539. Folding-sliding doors. KING, Ltd., G. W. Oct. 6, 1954 [Oct. 12, 1953], No. 28001/53. Class 20(3). A folding door comprises a plurality of of leaves or sections 10 interconnected and adapted when the door is in closed position to lie substantially flat in a common plane and when the door is in open position to be folded against each other in planes substantially at right angles to that of the door opening and each leaf or section carries a pivoted link 13, the outer or free ends of the two links on each successive pair of leaves or sections 10 being pivotally interconnected in the region of their free ends and adapted to support, in line with the hinge or fold axis of their associated leaves or sections, means, such as freely rotatable rollers 12 or a roller 12<SP>1</SP>, adapted to engage a fixed guide track 11 or 11<SP>1</SP> which extends across the door opening and arranged so that on movement of the door into or out of its opened or folded position, a controlled folding or unfolding motion respectively will be imparted automatically to successive pairs of leaves or sections at a predetermined point A in the path of travel of the door. As shown, the track 11 (or 11<SP>1</SP>) extends across the door opening parallel thereto up to the point A where the folding commences, the track then being inclined outwardly from the door for a short distance and is then curved outwardly at B which allows the folding movement to continue till the leaves 10 are perpendicular to the opening, the track then continuing parallel to the opening for a short distance to accommodate all the folded leaves. In Fig. 1, the guide track 11 is a single rail engaged by a pair of rollers 12 which are mounted on a plate carried by the pin interconnecting the two pivoted links 13. In Fig. 4, the guide track 11<SP>1</SP> is of channel section, or may comprise parallel rails, in which a single roller 12<SP>1</SP> is mounted on the pin connecting the two links 13. Similar linkages may also be provided at the bottom of large doors to guide and break the hinge connections. To avoid undue strain on rollers and hinges at the point A, a chain drive may be mounted on the door lintel between the point A and the end of the folded leaves, to engage a pin on the top corner of each leaf 10 so that all the folded leaves are moved together by the chain as far as the release point. Alternate long and short pins on each pair of leaves 10 are necessary so that the leaves of each pair are released at the same time from the chain.