Patent GB-819004-A (GB)
Title: Improvements in or relating to sheet-feeding apparatus
IPC: B65H5/10
Filed: 1957-07-03
Abstract: 819,004. Feeding sheets. SCHNELLPRESSENFABRIK AKTIENGESELLSCHAFT HEIDELBERG. July 3, 1957 [April 20, 1957], No. 20952/57. Class 100(1) Sheet-forwarders:-The gripper carriage which feeds sheets over a feed-table 55, Fig. 5, up to register stops thereon adjacent the impression &c. cylinder 92 of a printing &c. machine, is driven by a connecting-rod which is connected at one end to the carriage and at the other end to a crank, both the crank and the connecting- rod being oscillated through an arc of approximately 180 degrees. In one form, Figs. 2, 5, 7b and 19, the operating parts of the feeder are supported on a crossframe 3 between frames 1, 2 and are driven from a one-revolution shaft 5 through bevel gears 6, 7. A crank 8 secured to the gear 7 is connected by a link 11 to one arm of a lever 13 pivoted on the frame 3 at 14, the other arm comprising an arcuate toothed rack engaging a pinion formed on a crank 16 pivoted on the frame 3 at 17, Fig; 7b. The crank 16 has pivoted theron at 19 a connecting-rod 21, the free end 22 of which is guided by a roller or rollers for rectilinear movement between a pair of guides 26, 27, and is connected to the gripper carriage. An extension 21<1> of the connecting-rod 21, and of equal length, has a roller 24 engaging a slot 28 which is at right angles to the guides 26, 27. When the crank 16 is oscillated through an arc of 180 degrees the end 22 of the connecting-rod 21 (and hence the gripper carriage) moves in a rectilinear path between its guides through a distance four times the length of the crank, and the roller 24 on the rod extension 21' moves along the slot 28 and back to stabilise the motion and assist in overcoming " dead centres. The end 22 of the connecting-rod 21 has a guide 32 thereon connected to straps 35, 36 which engage a spindle 39, Figs. 2 and 19, which carries the grippers 40-43. In the modification shown in Fig. 9, the oscillating toothed arc 13 meshes with a gear 101 fast with a crank 100 having pivoted at its free end 102 a connecting-rod 104 which is connected at 111 to the gripper carriage, and guided for rectilinear motion as before. A planetary gear 105 fast with the rod 104 meshes with a gear 106 pivoted on the crank 100, and the gear 106 meshes with a fixed sun-wheel 108. When the toothed arc 13 is oscillated, the crank is oscillated through about 180 degrees, and the end 111 of the connecting-rod 104 executes a linear motion due to the rolling of the gear 106 over the sun-wheel 108. In another modification (Fig. 13, not shown), the arrangement of Fig. 9 is duplicated, so that there are two cranks, and two connecting-rods which are coupled together and connected to the gripper carriage. Feed-tables:-The feed-table 55 is arranged between the sheet pile 90 and the impression cylinder 92, and is provided with longitudinal slots to allow the sheetgrippers 40-43 to protrude during feeding. The table may be flat, or curved as shownin Fig. 5. Grippers:-The gripper carriage consists of the spindle 39, Figs. 2 and 19, having gripper pads secured thereto co-operating- with grippers 40-43 which are secured to a stirrup 39<1> rotatably mounted on the spindle. The grippers are closed on the pads by torsion springs 39<11> acting on the stirrup 39<1>. Levers 44, 45 secured on the spindle 39 carry rollers which, together with rollers on the ends of the spindle, run in guide rails 53, 54 which are curved to suit the shape of the feed-table 55. In order that the grippers can project slightly through the slots in the feed-table when feeding a sheet over the table, and be retracted to a lower position when returning for another sheet, the curved guide rails 53, 54 are moved upwardly and downwardly by cams on the drive shaft 5. The gripper carriage thus performs a movement transversely to its direction of feeding motion. The grippers are opened and closed at the receiving and delivery points by means of abutments 88, 87, Fig. 5, respectively, which are on the ends of a .long double lever 84 pivoted on a bracket on the cross-frame 3, and rocked by a cam disc 86 on the shaft 5. In these two positions, the abutments rock a roller 89 on the gripper carriage which causes the grippers 40-43 to be opened. The double " dead " centre drive of the carriage causes the carriage to pause at the end of each stroke to allow the sheets to be gripped and released.