Patent GB-701949-A (GB)
Title: Improvements in and relating to folding and sliding door installations for trolley-bus garages
IPC: E06B3/48
Filed: 1951-12-21
Abstract: 701,949. Doors. EDUCATIONAL SUPPLY ASSOCIATION, Ltd., and MALES, M. Dec. 19, 1952 [Dec. 21, 1951], No. 29981/51. Class 20 (3) A sliding and folding door for a trolley-bus garage of the kind in which each door is composed of a number of uprights 14, 14', 14" arranged to slide horizontally in upper and lower guides across the door opening, pairs of leaves being hinged between each pair of uprights to form a door which can be extended, or collapsed concertina-wise, is characterized in that gaps are provided in the upper guide of the doorway to accommodate power wires for the trolley-buses, the gaps being bridged by track sections 17 pivotally mounted for movement into and out of the bridging positions-as the door is closed or opened. The lintel structure 10 of a doorway has two pairs of recesses 11, 11' accommodating power wires 12, 12'. An inverted steel channel 13 suspended below the lintel and having gaps registering with the recesses 11 forms a guide for horizontal rollers 16, 16', on the upper ends of the door uprights. Each gap in the channel is bridged by a section of channel 17 which carries a pivot pin 18 rotatably supported by a bearing plate 19 secured to the door lintel. Snapaction mechanism tending to lock the section 17 in a position either bridging the gap, or in a position at right angles to the fixed channel 13 comprises a pair of opposed rods 21 slidable in brackets 22 mounted on the bearing plate 19, the enlarged heads 20 being loaded by springs 23 to press against a squared part of the pin 18. A stop 30 is secured to the channel 13 to prevent the section 17 from being rotated out of alignment with the channel in a clockwise direction, rotation in an anti-clockwise direction being limited to about 90 degrees by a stop 24 mounted on the bearing plate 19. Mechanism for turnihg the section 17 into, and out of, alignment with the channel 13 as the door is closed, or opened, comprises an arm 26 which is attached to the leading upright 14 and which carries rollers 27, 28 mounted on vertical axes, the roller 27 being adapted to engage the cam face of a projection 25 on the section 17 when the upright 14 is moved to the right on opening the door and rotate the section 17 out of its bridging position, the reverse rotation of the section 17 being effected when the upright 14 moves to the left and the roller 28, meeting the side of the section 17, urges the latter into alignment with the channel 13 again. The arm 26 is stabilized by two rollers 31 which roll on the outer flange of the channel 13, a guard plate 29 being secured on to the top of the roller 29 to prevent the roller from slipping beneath the projection 25. A latch plate 32 is pivoted on the outer face of the inner flange of the channel 13 so that in one position, shown in dotted lines in Fig. 6, it will obstruct the section 17 and prevent it from being rotated out of the bridging position, and in the other position, shown in full lines, it lies clear of the section 17. A pin 35 fixed to the upright 14 moves the latch 32 into its obstructing and non- obstructing positions as the door is closed and opened.