Patent GB-861303-A (GB)
Title: Sheet feeder for printing presses and other sheet handling machines
IPC: B65H5/24
Filed: 1957-08-08
Abstract: 861,303. Feeding sheets. HARRIS-INTERTYPE CORPORATION. Aug. 8, 1957 [Aug. 16, 1956(2)], No. 25018/57. Class 100(1) In apparatus for stream feeding underlapped sheets to a processing machine, the sheets are each registered at the front and side whilst the preceding sheet partially overlies it, and side registration is effected by means which lift the preceding sheet and grasp the sheet to be registered from above and below. As shown in Figs. 2 and 4, sheets in underlapping relationship are fed by tapes 19 over a feed-board 18 up to front stops 20, and are then fed by driven rollers 21 and co-operating drop-rollers 22 to the grippers 17 of a cylinder 15, which may be an impression cylinder, or an auxiliary feed cylinder, in a printing-machine. A lifting finger 24, tapered at the front end, moves transversely inwardly in a slot 14 in the board 18 and beneath a sheet S <SP>1</SP> at a time before the front edge of an underlying sheet S<SP>2</SP> arrives at this point; the finger then moves up to lift the edge of the sheet S<SP>1</SP> and allow the next sheet S<SP>2</SP> to pass beneath the finger. The finger 24 then moves down to grip the sheet S<SP>2</SP>, which is now registered by the front stops 20, against an idler roller 26, after which it moves out to pull the sheet outwardly against a side registration gauge 25. Next, the finger 24 moves out beyond the feed-board 18 and downwardly preparatory to its next inward movement. The finger 24 is transversely slidable in a bracket 28 vertically slidable on a frame portion 27 under the action of a roller 33 bearing on a cam 34 secured to a shaft 35 which rotates once for each printing press cycle. In and out movement of the finger 24 relatively to the feedboard is by a pivoted lever 36, having a roller 38 engaging a groove in a barrel cam 39 fixed on the shaft 35, connected by a link 40 to the finger. The roller 26 is mounted on an arm 29 pivoted to the bracket 28 and urged upwardly by a compression spring 31 against a stop 32 so that the roller remains at the level of the board 18. In the modification shown in Figs. 16 and 18, a gauging finger 133 moves inwardly of the feed-board 18 above a roller 132 and beneath the first sheet S<SP>1</SP>, then downwardly to press the second sheet S<SP>2</SP> against the roller and outwardly to draw that sheet against a side gauge 25, but a sheet-lifting finger 128 first lifts a side edge portion of the first sheet S<SP>1</SP> to the dotted line position, shown in Fig. 18, before the finger 133 moves inwardly. There are two radial fingers 128 on a hub secured to a shaft 126 which rotates through an angle of 180 degrees for each press cycle. The shaft 126 is rotated rapidly to bring a finger 128 up through a slot in the board 18 to lift the edge portion of the first sheet S<SP>1</SP>: this recurs shortly after the feed rollers have gripped the sheet S <SP>1</SP>. The shaft 126 may be rotated by a Geneva mechanism which provides an extended stop period and relatively short periods of acceleration, constant speed, and deceleration.' The finger 133 is integral with a vertical post 134 having a castor 135 adapted to run on a plate 144 which is arranged to be swung up and down by cam means. An L- shaped bar 137 engages in a groove in the post 134 and is extended to accommodate a coil spring 138 which presses the post downwardly. The bar 137 is grooved to receive a fixed guide 1381, and carries a roller 140 which runs in a groove in a barrel cam 142 secured on a shaft 143. Thus both vertical and horizontal movements are imparted to the finger 133. Since the edge of the first sheet S<SP>1</SP> is raised by the finger 128, the finger 133 moves in between the sheets S<SP>1</SP>, S2 without touching either of them. In order to allow more time for registration the cylinder 15, to which the sheets are fed, may be driven at non-uniform speed by an arrangement as described in Specification 743,453, whereby the rear edge of a sheet is moved rapidly over the feed-board 18 by the grippers 17. Specification 676,389 also is referred to.