Patent GB-947819-A (GB)
Title: Strip folding device
IPC: B41J15/16
Filed: 1961-08-25
Abstract: 947,819. Folding paper. CLARY CORPORATION. Aug. 25, 1961 [Sept. 2, 1960], No.30721/61. Heading B6H. A zig-zag folding machine for strips of paper or the like comprises a guide way 22 for a strip 11, a guide wall 41, 59 being disposed at one end of the guide way and extending substantially perpendicular to the guide way, a zig-zag folding accumulator 23 receiving the strip 11 from the guide way 22, drive means reciprocating the accumulator along the guide wall and past the guide way so as to form and accumulate folds of the strip, springs 42 on the accumulator for pressing accumulated folds of the strip against the guide wall, and means on the accumulator for retaining folds of the strip. The strip 11 is fed from a supply spool (not shown) round the surface of a block 10 against which it is held by spring clips 12, 15 and passes between a type cylinder 13 and platen hammers 14 mounted in the block 10, which cylinder and hammers may constitute any known type of selective printing device. The strip is weakened by transverse rows of perforations at the positions where it is to be folded. After passing round a friction roller 16 the strip enters a guide-way 17 which communicates with the guide-way 22, and passes round a sprocket roller 18, pins 19 on which engage perforations at each edge of the strip. The accumulator 23 comprises a frame 32 which is mounted, by means of rollers 33 on the frame 32 which engage grooves 34 in the machine frame 27, for vertical reciprocation in the machine frame. The frame 32 carries two pairs of horizontally extending pins 37 on which a pressure plate 38 is slidably mounted, being urged to the left, Fig. 1, by the springs 42. The left-hand ends of the pins 37 engage in vertical guide grooves in the guide wall 41, 59. The folds of the strip 11 are accumulated on the pins 37 which pass. through aligned sets of the edge perforations in the strip. The accumulator 23 is reciprocated vertically between a top position, shown in Fig. 1, and a bottom position in which it is aligned with the guide wall part 59 by means of connecting rods 45 driven from a pair of crank discs 43 on a shaft 44. The shaft 44 and sprocket cylinder 18 are driven from a shaft 20 on which is mounted the friction roller 16 and which is itself rotated intermittently by means not shown, in synchronism with the action of the platen hammers 14. The roller 16 has a slightly larger diameter than the roller 18 so that when the two rollers co-operate to advance the strip any tension between the strip and the feed pins 19 is removed. When the accumulator is in its upper position a transverse line of perforations in the strip is positioned at 58 so that as the accumulator starts its downward stroke the strip folds on this line and moves downwards so that the fold is creased between the guide wall part 59 and a previous strip fold. When the accumulator reaches its bottom position another line of perforations is at the position 58 so that a second fold is made by the accumulator in the course of its upward travel. A cavity 21 in the guide-way 22 allows for the temporary build-up of slack in the strip which is caused by the fact that the sprocket roller 18 rotates at a constant speed while the accumulator 23 reciprocates at a continously varying speed owing to its drive through the crank discs 43. In a modification, Fig. 4, the accumulator is driven at a constant velocity by means of a pair of rack frames 196, coupled to the frame 32 and having teeth 97, 98 which are engaged successively by the teeth 96 of a pair of mutilated gears 95 mounted on the shaft 44 so as to provide downward and upward motion respectively of the accumulator. The accumulator is emptied by the withdrawal of a pin 91 which locks the guide wall part 41 in position in the machine frame and by pivoting this part away from the accumulator about pins 94. Specification 928,860 is referred to.