Patent GB-843799-A (GB)
Title: A sheet feeder
IPC: B21D43/09
Filed: 1957-12-19
Abstract: 843,799. Punching. TECHNICAL DESIGN & DEVELOPMENT CO. Inc. Dec. 19, 1957 [Dec. 26, 1956], No. 39469/57. Class 83 (4). [Also in Group XVI] An apparatus for feeding superimposed lengths of material, e.g. of metal, singly to a blanking press comprises means for driving upper and lower feed rollers from the crank-shaft of the blanking press in timed relation with the operation of the press, an endless feed belt carried by supporting rollers mounted on a horizontal frame, a driving connection from the feed rollers to one of the beltsupporting rollers, and a pair of upright laterally-spaced guides adjacent opposite ends of the belt for retaining and guiding a stack of superimposed lengths of material to be fed singly from the belt to the feed rollers. As shown, a stack of lengths 20, Fig. 8, are supported on an endless belt 19, the upper run 19a of which is supported on a plate 68, Fig. 1. The belt 19 which may be of canvas or other woven material having a rubber surface vulcanized thereto passes around rollers 70 and 71, the roller 70 being mounted in bearings 72 supported on a fixed plate 73. The roller 71 is mounted in bearings 77 carried by a transverse plate 78 adjustable by screws 81 to vary the belt tension and position the roller at right-angles to the belt. To ensure that only the lowermost length 20 is fed to the feed rollers a vertical stop-plate 115, Fig. 7, is arranged with its lower edge 116 spaced above the top surface of a lower plate 96 a distance approximating the thickness of a length 20. The plate is vertically adjustable to vary this distance by a screw 117. An upright stop 90a, Fig. 3, not shown, prevents forward movement of the topmost lengths. The stack is maintained in position on the belt by guides 90, Fig. 5, preferably of U-shaped cross-section. Feet 92, supporting the guides, are adjustably clamped to a supporting-block 93 by a clampbar 95a and screw 95 to permit adjustment of the guides 90 according to the width of the lengths to be fed. Feed rollers 16 and 17, Fig. 8, are mounted by brackets 21 secured to the press and frame 10, the upper roller 17 being carried in supporting arms 31, Fig. 1, pivoted to extensions 33 of each bracket 21, thereby permitting up- and-down movement of the upper roller 17 by actuation of a finger 48. The finger 48 is engaged by a bolt 57 on the vertically-reciprocating ram 55 of the press during its downward movement to separate the feed rollers, thus releasing the length 20 to permit correct positioning by locating-pins on the press dies. An adjustable crank 58 actuated by the press crank-shaft has a connection 59 to an operating lever, not shown, which rotates the lower feed roller 16 through a one-way clutch, not shown. Reverse movement of the rollers is prevented by a brake 64 (Fig. 12, not shown). The rollers 16 and 17 are normally spaced slightly apart slightly less than the thickness of the material being fed, the setting being adjustable by studs 54 (Fig. 11, not shown), which limit the downward movement of the arms 31. A sprocket 87, Fig. 1, on the shaft of the roller 16 drives a chain 88 passing around a sprocket 89 on the end of a roller 70, the sprocket 87 being larger than the sprocket 89 to cause the belt speed to exceed that of the feed rollers. Thus, the forward end of a length being fed by the belt abuts the trailing end of the previous length being fed through the rollers. A plate 101, Figs. 8 and 9, is spaced from the plate 96 by spacing strips 101a to form a guide for lengths of material being fed. The plate 96 has depending ribs 96a forming a recess housing longitudinally-extending electrical heating units 97 supported on clamping bars 98. Similarly, heating units 106 are housed in a recess 105. The heating units 97 and 106 heat lengths 20 of the material to suitable temperature for blanking, as they are fed to the press, thereby obviating cracking. The plates 96, 101 have recesses 110, 111, for the rollers 16, 17, the recesses being separated by a bar 112 (Fig. 12, not shown) extending through peripheral grooves, not shown, in the rollers. Preheated elements 12, Fig. 1, e.g. infra-red lamps, are mounted on brackets 124 on either side of the stack of strip lengths 20; the brackets 124 may be swung downwardly and outwardly for inspection &c.