Patent GB-676389-A (GB)
Title: Improvements in or relating to mechanism for feeding sheets to a printing or other sheet handling machine
IPC: B41F21/10
Filed: 1950-05-18
Abstract: 676,389. Feeding sheets. HARRIS-SEYBOLDCO. May 18, 1950 [May 24, 1949], No. 12444/50. Class 100 (i). Sheet carriers.-In apparatus for feeding sheets to a rotary printing or other machine, including a revolvable advance cylinder 11 which grips the forward edge of a sheet, a rotatable transfer device 12 which presents sheets to the grippers 56 of the advance cylinder, and a sheetengaging abutment 68 mounted on, and adapted to swing outwardly and inwardly of, the advance cylinder to form a temporary loop in the intermediate portion of a sheet as the forward edge of the sheet travels with the grippers, the sheet-engaging abutment 68 travels in an oval path 95, the major axis of which is disposed approximately radial to the advance cylinder 11. As shown, sheets on a feed board 13 are fed by rollers 38, 41 to grippers 54 on a transfer cylinder 12 which transfers them to the grippers 56 on the cylinder 11. The sheets are then transferred to grippers 57 on an impression cylinder 10 of a rotary printing- machine. The transfer cylinder 12 is driven in known manner, from the cylinder 11, partly through segmental gears 17 and partly through fish-tail cams 25, 26, 27 in the cylinder 12, which are engaged, respectively, by a gear 15 and rollers 21, 22, 23, 24 on the cylinder 11. This drive provides the cylinder 12, in each revolution thereof, with a stationary period, an accelerating period, a constant speed rotation period, and a decelerating period. The sheets are registered against stops 49 on the feed board 13, and fed, at a faster speed than the peripheral speed of the cylinder 12, by the rollers 38, 41 to the grippers 54 on the cylinder 12. When the front edge of a sheet has been grasped by the grippers 56 on the cylinder 11, the rear edge of the sheet is rapidly withdrawn from the feed board by rollers 68, which swing outwardly of the periphery of the cylinder 11 to form a loop in the sheet. The sheet is kept in contact with the transfer cylinder 12 by a series of stationary brushes 93, which also provide a drag on the sheet tail when the loop is being taken up. The rollers 68 are freely mounted on an arm 67 keyed to a stub shaft 66 journalled in the walls of the cylinder 11, the latter being suitably recessed to accommodate several such shafts 66 and to allow retraction of the rollers 68 within the periphery of the cylinder. One end of the shaft 66 extends beyond the side of the cylinder 11, and a pinion 70 keyed thereon meshes with a pinion 71 which is integral with a gear 73 and freely mounted on a stub shaft fixed in the end wall of the cylinder. The gear 73 meshes with a ring gear 74, freely mounted on the shaft 60 of the cylinder 11, which meshes with a gear sector 75 fixed to a hub 76 mounted to oscillate on a trunnion 77 (not shown) fixed to the machine frame. The sector 75 can be adjusted relatively to the hub 76, and the trunnion 77 is eccentrically mounted. Two arms 85, 86 of the hub 76 have rollers engaging, respectively, cams 89, 90 of identical shape mounted to rotate with the shaft 60. In operation, the cams 89, 90 oscillate the gear sector 75 which, through the sun wheel 74 and gears 73, 71, 70, swings the rollers 68 outwardly and inwardly of the periphery of the cylinder 11 following the oval path 95. Specification 643,542 is referred to.