Patent GB-370862-A (GB)
Title: Method and means for the separation of sheets in sheet feeding apparatus for printing presses, folding machines and the like
IPC: B65H3/08
Filed: 1930-10-06
Abstract: 370,862. Feeding sheets. AKTIEBOLAGET DUX, 13, Ynglingagatan, Stockholm.-(Assignees of Stromberg, N. G. A. ; 34, TegnÚrgatan, and Widlund, G. W. ; 38, G÷tgatan, both in Stockholm.) Oct. 6, 1930, No. 29847. Convention date, Oct. 7, 1929. Void [Published under Sect. 91 of the Acts]. [Class 100 (i).] Sheet-separators; pile supports.-In a sheetfeeding apparatus for printing-machines, folding-machines, &c., of the kind in which the forward edge of the top sheet is engaged by a suction sheet-forwarding device and the rear edge by a sheet-separating device, the separating device is formed as a series of suction nozzles 35 connected to a rotatable suction tube 33 carried by tipping arms 37, 38 which are operated to cause the suction nozzles to bend up the rear portion of the top sheet as shown in Fig. 3, after the nozzles have been moved down on to pile in such a manner.as to engage the sheet squarely. The nozzles are then raised from the pile, and are returned to their original horizontal position, and a front presser-foot 23 is raised to permit of the advance of the sheet by the sheet-forwarding device. A rear presserfoot 17 is then moved under the separated sheet parallel to the top of the pile, and before moving on to the pile, the edge of the pile is squared by an angular member 18 attached to the foot 17 which finally is moved downwards on to the pile. The suction in the nozzles is then released and the sheets advanced by the front sheet-forwarding device. The separation of a single sheet only is assisted by air blasts from pipes 45 connected to a pipe 44 which is carried by bell cranks 39 to which the tipping arms 37, 38 are pivoted. The edge of the pile is acted on by blasts from tubes 47 connected to a fixed tube 46. When the sheets have been advanced a given distance, the front presserfeet 23 are released and move down to grip the sheet against the pile with its advanced edge projecting a fixed distance from the front of the pile. The suction of the forwarding device is then released, and the sheet is taken by the grippers of the press. The nozzles 35 then descend and the presser-foot 17 moves backwards, and the operations described above are repeated. The bell cranks 39, which raise the nozzles, are operated by rollers 42 engaged by cams 43 on the main cam shaft 8, and, owing to the independent actuation of the bell cranks 39, the nozzles adapt themselves to piles which are not exactly horizontal. The angular movement of the nozzles is obtained from cams 49 which oscillate levers 48 connected by links 51 to the tipping arms 37, 38. The pivots 52, 53, 40, 41 form a parallelogram, so that the suction nozzles when raised maintain the same direction during their lifting movement. To adjust the angle of tip of the nozzles, the levers 48 are controlled by a pivoted rod 54 fitted with an adjustable nut 56 which engages a bracket 58 to limit the forward motion of the lever 48. A spring 60 serves as a buffer, and a spring 59 maintains the lever 48 in engagement with its cam. The presser-foot 17 is operated by an oscillating lever 12 and also by levers 14, 15 and link 16. The levers 12, 14 are operated by cams on the shaft 8. The presser-foot 23 moves through a stirrup 32, and is depressed by a spring 27 and raised against the action thereof by a lever 28 which acts on a stud 25 on the stem 24 of the presser-foot. The frames in which the sheet-feeding members are mounted are adjustable in a frame 1 formed of U-irons, so as to adapt the machine to sheets of different sizes. The sheet-forwarding mechanism may be of the kind described in Specification 331,435, [Class 100 (i), Feeding and delivering webs &c.].