GB1431343A - Transferring plies of limp sheet material from a stack - Google Patents

Abstract

1431343 Feeding and delivering sheets USM CORP 5 June 1973 [6 June 1972] 26658/73 Heading B8R A pick-up device for separating sheets from the top of a pile comprises a member which presses on the pile so as to cause the sheets to bulge upwards in the vicinity of engagement with the pressing member, and a separator element which engages the top sheet in the bulged portion with a light pressure and is mounted so as to be allowed vertical movement relative to the pressing member, so that as the top sheet bulges upwards, the separator element floats upwards with it. The pick-up device comprises a presser foot 4, Fig. 6, vertically slidably in a tubular member 13, and carries a separator element 1 having rigid inclined points to engage the top sheet, the element 1 having a slot 31 engaging a pin 6 on the foot 4 to allow relative vertical movement, and having a cam surface 2 which engages the bottom of the member 13 so that when the members 1, 4 rise in the member 13 by the pressure of the stack moving upwards, the member 1 is pivoted clockwise against the action of a spring 5, so as to clamp a fold of the sheet between itself and a protruding ledge portion of the foot. Further upward pressure of the pile forces a recess 8 in an inclined surface 7 of the member 13 away from a detent 11, Fig. 8, and a spring 10 acting through the detent on the surface 7 forces the assembly 13, 1, 4 upwards carrying the sheet until the detent engages a recess 9. Another form of pick-up device, Figs. 14-19 (not shown) is the same as that described in Specifications 1,431,342 and 1,431,344. Another form of pick-up device, Figs. 21, 23a, 23b, comprises an arm 201 carrying a presser member 203 with a clamping portion 225. Slidably mounted on the member 203 is a member 205 carrying a separator element 221 having metal card cloth teeth 223. When the top sheet bulges upwards at B, it moves the element 221 up against light springs 209<SP>1</SP>, 211<SP>1</SP>, clear of a catch portion 217 of the member 203, whereupon a spring 215 moves the member 205 to the left to clamp a fold of the sheet between the element 221 and the clamping portion 225. The arm 201 is then raised to the broken line position of Fig. 21. Several pick-up devices may be used spaced over the sheet. Forwarding and stacking.-Compressed air introduced into a line 231 forces a piston 233 carrying the member 205 to the right to bring the sheet into depositing position over a stack. A shoulder 220 of the member 205 strikes the catch portion 217 and jerks the element 221 up to release the sheet.