Patent GB-286028-A (GB)
Title: Improvements in or relating to paper-separating devices for paper-feeding machines
IPC: B65H3/08
Filed: 1926-12-13
Abstract: 286,028. Liljebladh, E. H. Dec. 13, 1926. Sheet-separators.-In sheetfeeding mechanism for printing or similar machines in which each sheet is separated from the pile 100, Figs. 2 and 7, by means of a suction foot 15 disposed near the rear edge of the pile, the upward movement of the suction foot is arranged in such a direction that no movement of the front edge of the sheet is caused by the consequent bending of the sheet. The suction foot 15, which has two angularly-disposed faces 42, 42a, is pivotallymounted at 14 on a forked holder 9 carried by rods 10, 11 slidable in guide bushes 7, 8 formed integrally with a sleeve 1 on which the separating-devices are mounted. The bushes 7, 8 are inclined towards the forward edge of the pile 100 so that the foot 15 as it rises moves slightly in the direction of feed and the front edge of the sheet is thus cause to remain stationary. The sleeve 1 is adjustable by means of a hand-screw 3 along a bar 2 extending in the direction of feed and carried at one end by a link 78 pivoted to the machine framing 71 and at the other end by a horizontally-adjustable bracket 5 in which its end is adjustable vertically by means of a screw- and-slot device 4. Lugs 13, 18 on the holder 9 and foot 15 are connected by a bolt-,and-slot arrangement 16, 17 so that the inclination of the foot can be adjusted. A crank 90 on the. holder 9 has a pin 900 engaged by a slot 190 in a bellcrank lever 22 pivoted to the sleeve 1 at 21, the other end of the lever being pivoted to a split sleeve 24 adjustably secured to a reciprocating rod 25 by means of a screw 23. A suction chamber 27 is mounted on the top of the sleeve 1 and is connected by a flexible tube 73 to a pump 74 and by two flexible tubes 29 to the foot 15. A valve 32 is provided for controlling the suction. The suction foot 15 has rearwardly-extending lugs 43 to which are adjustably-pivoted, by means of screws 45, nozzles 44 adapted to direct a current of air parallel to the inclined face 42a of the foot 15, so as to prevent more than one sheet being carried up by the foot. A second set of nozzles 48 are situated to the rear of the pile 100 so as to direct a current of air along and parallel to the surface of the pile for the purpose of loosening the upper sheets. The nozzles 48 are formed by vertical slots 51 in tubes having inclined bases and verticallyadjustable in brackets 49, which are adjustable horizontally along a bar 50. The sets of nozzles 44, 48 are connected by flexible tubes 46, 47 to sockets 37, 36 respectively on a compressed-air chamber 35 mounted on the main sleeve 1 and connected at its upper end to a pump 76 by a flexible tube 75. A pivoted baffle 38 separates the respective sockets 36, 37, and a coil spring on its spindle 39 tends to close it and cut off the nozzles 48 from the pump 76. While the foot 15 rests on the pile 100 and during its initial movement, however, the baffle 38 is kept open by the engagement of a pin 41 on the rod 10 with an arm 40 attached to the spindle 39, so that initially both sets of nozzles are in operation, but when the sheet is separated from the pile, the nozzles 48 are put out of operation and the current through the nozzles 44 correspondingly increased. A presserfoot 56, Figs. 2 and 6, is adapted to rest on the pile 100 after the top sheet has been separated, and is pivoted at 57 to a bracket 53 slidably mounted on a rod 52 fixed to a bracket 520 on the sleeve 1 parallel to and below the bar 2 by which the bracket is guided. An arm 58 on the spindle 57 is adjustably connected by means of a screw 59 and split sleeve 60 to a reciprocating rod 61. A U-shaped member 62, pivoted on the foot 56, is caused by a spring 66 to engage with a curved surface 63 on the bracket 53 when the foot is raised so as to hold it raised, but is adapted to be pushed off the surface 63 to allow the foot to drop by a pin 68 as the bracket 63 moves to the left. A spring 70 tends to move the bracket 63 to the left, and a set-screw 69 on the foot 56 limits the upward movement of the foot 56 by engagement with the underside of the bracket 53. In operation, assuming that the foot 56 is initially resting on the pile 100, the rod 52 starts moving to the right. During this movement, the bracket 53 is prevented by the spring 70 from moving to the right until the foot 56 is lifted and the screw 69 contacts with the bracbet. When the bracket 53 begins to move, the spring 66 forces the member 62 into engagement with the surface 63. By this means, during the reverse movement, premature dropping of the foot is prevented, and the parts 53, 56 move together until the pin 68 pushes the member 62 off the surface and the foot 56 drops on to the pile 100.