Patent GB-919791-A (GB)
Title: Improvements in sheet-feeding apparatus
Inventor: MAUDSLEY BRIAN GRANVILLE
IPC: B65H3/46
Filed: 1960-08-18
Abstract: 919,791. Feeding and delivering sheets. SOLARTRON ELECTRONIC GROUP Ltd. Aug. 18, 1961 [Aug. 18, 1960], No. 28690/60. Class 100 (1). [Also in Group XXX] Separators.-Sheets such as football-pool coupons are fed one at a time from the bottom of a stack resting on a table 10, by a rotating suction roller 12, spaced suction ports 20 being provided along the rear edge of the table to prevent double feed by restraining the second sheet up in stack against the frictional pull imparted thereto, on feeding the bottom sheet. Initially, the bottom sheet is fed a short distance by the suction roller against the action of the suction ports which are then uncovered to engage said second sheet. The suction roller is barrelshaped and projects through a slot in the table, so as to bend up one edge of the stack. The slot is bridged by curved strips 17 accommodated in annular grooves in the surface of the roller 12 and air is sucked down through the narrow gaps between the long edges of the slot and the periphery of the roller to increase the bending effect on the bottom sheet. Further, due to the barrel-shape of the roller, the sides of the bottom sheet are pulled away from the overlying sheets to lessen the frictional restraint on the bottom sheet and lend stiffness thereto in the direction of motion. The front edge of the stack abuts an inclined transparent plate 13 provided with a cut-away portion 18 through which a blast of air is directed from a pipe 19. The roller 12 is provided with suction apertures 15 around only part of its periphery, the rest presenting a smooth rubber surface 14. The sheets are fed to accelerating rollers 22, 23, which take up a sheet as the apertured section 15 passes beneath the table leaving the sheet free to slide over the smooth surface 14. Alternatively, the roller 12 is apertured all round and is driven through a freewheel to allow for acceleration of a sheet by said rollers 22, 23. Sheet carriers and forwarders.-The sheets are fed to an endless conveyer 24, provided with cooperating hold-on tapes 25 and straightened thereon by skewed rollers 27 which move them transversely of the conveyer into engagement with a V-shaped side rail 28, so that a side edge of each sheet projects beyond the conveyer belt. The sheets pass from the conveyer 24 over a table 29, Fig. 3 (not shown), between an upper roller and co-operating, spaced, lower discs, having raised rubber rims extending over a part of their peripheries, to a gate which emits the sheets at regularly-spaced intervals to a second endless conveyer. The gate comprises a series of bent wires spaced along a spindle which is rocked to raise the gate in time relation to the rotation of the discs. The second conveyer moves the sheets beneath photo-electric sensing means, provided with a light trap, which determines into which category the sheet belong and operates the appropriate receiving station (described below) after the elapse of time taken by the sheet to reach the receiving station in question. Delivering sheets.-Corresponding to each category is a receiving station comprising a continuously rotating take-off roller 71 over which the projecting edges of the sheets pass. The sheets are held on the conveyer against the action of the take-off rollers by hold-on tapes (not shown) and the projecting edges supported by ledges 72 between take-off rollers. Two rollers 74 fixed to the armature of a solenoid 77, are associated with each take-off roller. Operation of the solenoid by the sensing means, moves the rollers 74 downwardly on to the take-off roller to move a sheet transversely of the conveyer to a series of endless belts and co-operating tapes moving at progressively-decreasing speeds, whereby the sheets are decelerated and delivered to the stacking table 94 in overlapping fashion. Alternatively, the conveyer from the sensing means comprises a number of endless belts 100 bridged by plates 101, one for each category, across which the sheets slide. On lifting the plate 101 by a solenoid 102 controlled by sensing means, a sheet is fed a short way by the return run of the conveyer 100 and cooperating tapes 103. The sheet is removed from the latter by a perforated belt 104 behind which a vacuum box 106 is mounted. On interrupting the vacuum the sheet drops on to a slowly-moving belt 107. A wire brush 109 smooths out the sheets before they reach the belt 104.