Patent GB-992112-A (GB)
Title: Improvements in and relating to sheet folding machines
Inventor: BYE ALFRED ROBERT
IPC: B65H45/12
Filed: 1961-04-05
Abstract: 992,112. Folding paper. ENGLISH ELECTRIC CO. Ltd. March 28, 1962 [April 5, 1961], No. 12108/61. Heading B6H. A machine for making zig-zag folds in paper sheets of varying widths comprises a table 2 on to which the sheets are fed by feed rollers 3. The rollers 3 feed a sheet over the table 2 until the leading edge of the sheet is located under a series of forward clamps 4 which then move downwards to clamp the leading edge to the table. When the leading edge is clamped the upper feed roller 3 is raised by a solenoid so that the trailing part of the sheet is free to move under the action of the folding mechanism. Two pairs of arms 5, 6, for narrow and wide sheets respectively, mounted on the upper side of the table 2, are arranged to pivot about vertical axes from positions parallel to the direction of movement of the sheets to positions normal to that direction so as to swing inwards over the sheet and then move downwards to hold the sheet on the table 2 at a position 10 inches to the rear of the clamps 4 when the latter clamps have been lowered. A folding bar 7 having recesses 7a in its leading edge aligned with the clamps 4 is then moved horizontally from a position to the rear of the arms 5, 6 towards the clamps 4. During this movement it engages the sheet and carries it forward in a V-shaped fold. As the folding bar approaches the clamps 4 the latter are raised so as to allow the paper folded over the leading edge of the folding bar to be aligned with the leading edge of the sheet. When the leading edge of the bar is aligned with the leading edge of the sheet the clamps 4 are lowered into the recesses of the bar and press the leading edge of the fold of paper down on to the leading edge of the sheet itself, simultaneously forming a crease therein. The bar is then moved back to its rear position, the arms 5, 6 are swung outwards and a series of rear clamps 8 move down to press a crease in the rearward directed fold of paper adjacent to the arms. At this stage a Z-shaped fold, 10 inches wide, has been produced in the paper. The cycle of operations is repeated automatically, each cycle producing a further fold until the length of the sheet has been exhausted. If a narrow sheet has been folded a pair of solenoid-operated pressing shoes is lowered to compress the folded sheet, which is then engaged by lugs 12 projecting through the table 2 from an endless chain 13 and the sheet is moved from under the clamps 4, which are raised for this purpose and into the nip of a pair of rollers 14 from which it is discharged into a receptacle at the end of the machine. A slot 15 is provided in the table 2 for the delivery of wide sheets of paper. A creasing bar 16 is mounted for vertical movement downwards into the slot 15, this movement causing the folded sheet of paper to be pressed downwards into the slot and simultaneously folded on its centre-line. Pairs of rollers 81, 82 are located below the slot 15 with their axes parallel thereto to receive the sheet, to press the centre crease and to discharge the folded sheet through a shoot 83 on to a conveyer belt 84. The timing of the movements of the moving parts of the machine is controlled by photo-electric cells PEC1-PEC4, the action of the arms 5 being cut out automatically by means of the cell PEC3 when wide sheets are to be folded.