Patent GB-230684-A (GB)
Title: Improvements in or relating to sheet feeding machines
IPC: B65H3/46
Filed: 1924-06-06
Abstract: 230,684. Wade, H., (Cross Paper Feeder Co.). June 6, 1924. Sheet-separators; dropping-roller feeds; sheet-guides.-Sheets are fed to printing &c. machines from a continuous bank of feathered sheets by sheet separating and forwarding devices which separate the sheets without a rubbing pressure, so that printing sheets can be fed without liability of being smeared. The sheets are fed over a table 6 formed at its front end with oscillating fingers 12 which bend the front ends of the sheets upward into contact with two sheet retainers, in the form of suction cups 14, carried at the end of suction tubes 16 mounted on brackets 40 laterally adjustable on a supporting shaft 44. The tubes 16 are telescopically mounted in tubes 28 and are normally projected by springs, but when the cups 14 contact with the top sheet and the tubes are put into communication with an exhaust pump by a camactuated valve, the tubes 16 are drawn into the tubes 28 so as to draw the top sheet away from those below which are returned with the fingers 12 to normal position. As the sheets are flexed and released. their edges are acted on by air blasts from blowers 22, Fig. 8, which prevent the adhesion of more than one sheet to the sheet retainers 14. The sheets below the separated sheet are clamped by oscillating clamps 26 which are formed hollow so as to direct a blast of air between the separated sheet and the bank. The separated sheet is released from the retainers 14, by breaking the vacuum in the tubes 28, after it has been seized by other suction cups 18 mounted on spring-controlled pivoted tubes 20, which are movable vertically with cam-operated slides 66 and horizontally with cam-operated slides 32 movable to the left, Fig. 8, under spring action when permitted by the cams. As the slides move to the left, the separated sheet is carried over the clamps 26 between feed rollers 8, 10, and is directed by a guide 100 into contact with sheet-stops 34, which are moved by the sheet so as to cause pawls 36 integral with them to engage racks on the slides 32 and thus automatically limit the forward movement of the separated sheet. Movement of the separated sheet is finally continued by the rollers 10, 8 when the top rollers are dropped into contact with the bottom ones. To ensure a sharp bend in the sheets, a bar 252 is preferably arranged just above the front edge of the bank, and the downward movement of the tubes 20 is preferably limited by stops, such as rollers 254, which prevent the engagement of the ends of the tubes 20 with the bank. Pile tables and supports.-The sheets are fed from a supply table 2 through a throat 4 and over a table 6 by means of feed bands 172, 174, which are actuated by devices controlled by the front end of the bank to maintain it in proper relation to the front end of the feed table. A feeler finger 212, Fig. 3, on an oscillating lever 244 is normally prevented by the sheets from engaging a recess 230 formed in the feed table. If, however, the sheets need advancing, the finger 212 descends far enough for the upper end of the finger to actuate an arm 220 on a shaft 200, and the shaft 200 is rotated and thus frees a stop-pawl which normally prevents the actuation of a pawl serving to rotate the shaft of the pulley 180 in a counterclockwise direction. The pulley 180 is thus allowed to be actuated and the feed belts are moved. The rear edge of the top sheet of the bank is acted on by a pressing-device 232 which is raised as the top sheet is withdrawn by mechanism described in Specification 25663/02. Pressure rollers 248 also press on the top sheets of the bank.