GB817948A - Improvements in or relating to sheet separating and feeding apparatus - Google Patents

Abstract

817,948. Feeding sheets. MABEG MASCHINENBAU G.m.b.H. April 26, 1957, No. 13462/57. Class 100(1) Apparatus for separating sheets 7 from a stack 20 comprises two groups of suction cylinders 3, 4 arranged to operate alternately, the cylinders of each group being arranged, when they grasp a sheet, to be rocked in a clockwise direction, as seen in Fig, 1, so that the sheet is drawn initially away from the front stops 23. As shown, the sheets are forwarded from the stack in overlapping relationship. Each group comprises two cylinders carried by link quadrilaterals under the control of eccentric discs mounted on a driving shaft 25. The cylinders are given a backward and forward bodily movement for feeding the sheets 7 to feed rollers 14, and an up and down movement to contact the pile and raise the sheets, by eccentric discs 6, 6a, and 5, 5a acting respectively, on quadrilateral links 22a, 22d, and 21, 21a, pivoted about a fixed shaft 27. The two suction cylinders 3 are mounted on a common shaft in a link arm 2 the walls of each cylinder being formed with a number of suction nozzles 8 which are connected to an internal duct 8a in the arm 2. The two ducts 8a lead to a bore 8c connected alternately to a source of vacuum and the atmosphere by a change-over device controlled from the shaft 25. The link arm 2 is pivoted at one end to an adjustable link 6, and at the other end to the two links 22a, 22b. The two suction cylinders 4 are each similar to the cylinders 3. One is carried by a lever arm 2a supported at one end by an adjustable link 16, and at the other end by the link 21a; and the other is carried by links 16 and 21b. The means for rotating the cylinders 3 when they have grasped a sheet comprises a pinion 9, secured to the shaft of the cylinders, engaged by a rack 11 (not shown) on a rod which is slidable, in opposition to a spring, in a cylinder 10 pivotally mounted on the link 22b. A spring acting on the pivoted cylinder 10 urges the rack into engagement with the pinion 9. When the associated link quadrilateral swings to feed a sheet towards the feed rollers 14, the pinion 9 rolls over the rack and so gives a rotary movement to the cylinders 3 in a clockwise direction to stretch the sheet carried thereby. This rotary movement is stopped when the pinion 9 touches an adjustable stop 13, whereupon the rack rod moves into the cylinder 10 to compress the spring therein. An air blast is directed under the moving lifted sheet to raise the front edge sufficient to move over the stops 23. A similar rack and pinion arrangement is operated on each suction cylinder 4.