GB186463A - Improvements in or relating to sheet feeding and delivering mechanism for printing machines - Google Patents

Abstract

186,463. Linotype & Machinery, Ltd., Stern, C. L., and Bugler, A. V. July 18,1921. Sheet separators and carriers; pile tables.- A sheetfeeding apparatus, especially applicable for machines for printing multi - colour impressions, is constructed with a pile feed board which is interchangeable with the deliverv board of the machine so that a pile of printed sheets may be taken direct from the delivery to the feeding-appaatus from which the sheets may be fed in one direction if they are to receive a second impression on the same side, or in the opposite direction if the sheet is to be printed on the reverse side, the second feed comprising an arrangement of tapes for reversing the sheet. As shown in Figs. 1 and 4, a pile of sheets on a board 1 can he registered against either of two lays 57, the sheets being placed against the left lay 57 and forwarded to feed rollers 5 and bands 6 if a printed sheet is to have a second print superimposed on the first print. If a sheet is required to be printed on the back of a prior print the board 1 is rotated about a vertical axis and the edges of the sheet are placed against the right lay 57 and the sheets are separated and fed to rollers 8 and tapes 9, 11, 12, and are reversed and fed to the same path as taken by the sheets fed by the rolls 5. The sheets are separated by similar feeding-members 2, 3, which act independently to advance a separated sheet to the rolls 5 or 8, or which may act collectively to advance the separated sheets to either of these rolls. Each separating-mechanism as 3, Fig. 4, comprises a frame as 3 which is adjustable on rails 18 by gear wheels 19 which can move over fixed racks 23 on the rails. The sheets are separated by rising and falling suction devices 32 carried by a vertically reciprocating shaft 24 on a bearing 28 which is reciprocated by a cam on a shaft 25 driven by worm-gearing from the main-shaft. Two suction devices 32 are employed and in addition to the rising and falling motion described, these are given horizontal reciprocations by means of rods 35 operated by link 37 and lever 38 on a shaft 21 which is oscillated by a sector operated by a lever and cam on shaft 25. The suction devices can be set on shaft 24 so as to be near together, or so as to be far apart, the suckers 32 being arranged near totogether when acting on the following edge of a sheet, and further apart when acting on the leading edge of a sheet. The suckers 32 may also be given a tilting action so as to ruck up the edge of the sheet, and they are vertically adjustable by nuts 83, and are connected by flexible pipes to a shaft 44, and valve mechanism is provided to control the suction. The separation of the sheets is assisted by blasts of air from a pivoted blower 46 on a rod 49 operated by a cam-actuated lever 52. This cam raises the blower periodically and as it rises a pin 60 tilts the blower backwards. A blade spring 68 acts as a pressing-device to prevent feed of more than one sheet. The blower 46 and presser 68 can be held out of action when the adjacent sucker is engaging the leading edge of a sheet, and when the suckers engage the following edge of the sheet they are out of range of the pin 60 and so receive no tilting motion. In a modification only one set of suckers 32 is employed and each of these may be mounted to act on either edge of the sheet and to be given a movement to ruck the sheets away from the edge it is acting on, while a fixed blower assists to effect the separation of the sheet by acting on the rucked-up edge.