GB819796A - Improvements in or relating to sheet feeding apparatus - Google Patents

Abstract

819,796. Feeding sheets. WEAN EQUIPMENT CORPORATION. March 4, 1957. No. 7066/57. Class 100(1) Sheet-separators; pusher feeds. In sheetfeeding apparatus a sheet is lifted from a pile or support by suction means and is then pushed horizontally away from the suction means, the suction means being supplied with gas under pressure to destroy the suction effect and to blow the sheet away from the suction means at the moment the sheet is pushed away from the suction means. As shown, the suction separator 2 is attached by a rod 3 to a piston 4 in a cylinder 5 connected to a source of air under pressure to raise and lower the separator 2. The separator is connected by a flexible pipe 6 to a conduit 8 which communicates, alternately, with a source 12 of compressed air through a valve 11, and with a source 10 of vacuum through a valve 9. The valves 9, 11 are closed and opened, respectively in the positions shown, by springs acting on pistons 15, 19 in cylinders 16, 20. When, however, compressed air is supplied to the cylinders 16, 20 through pipes 17, 21 though a solenoid-operated valve 23, the valve 9 is opened and the valve 11 is closed. When a sheet or a portion thereof is lifted from the top of a pile by the separator 2, it is engaged by a pusher member 30 to move it horizontally to a position where it is engaged by sheet-forwarding means such as feed rollers. The pusher 30 comprises a U-shaped member 31 within which is a mass of rubber &c. 32, and is carried on the rod 29 in a position 28 in a cylinder 27 to which air under pressure is supplied. A switch 33 controlling a solenoid 26 on the valve 23 is adapted to be operated by the engagement of a shoulder 35 on the rod 29 with a switch arm 34. In operation, with the separator 2 fully raised and gripping a sheet, the solenoid 26 is energized, the valve 9 open, and the valve 11 closed, the pusher 30 approaches the edge of the raised sheet, Just before the pusher engages this sheet, the shoulder 35 operates the switch 33 to de-energize the solenoid 26. The valve 9 is now closed and the valve 11 opened, so that compressed air replaces suction in the separator 2 and the sheet is released quickly and repelled. Thus the pusher 30 can engage and push the raised sheet without opposition from the suction separator 2, and the face of the latter is not subject to wear. Several suction separators 2 may be used.