Patent GB-711272-A (GB)
Title: Improvements in or relating to sheet feeding machines
IPC: B65H1/30
Filed: 1950-11-02
Abstract: 711,272. Feeding sheets. BACKHOUSE, H. T. Oct. 23, 1951 [Nov. 2, 1950], No. 26796/50. Class 100 (1) Pile supports.-In a sheet feeding machine of the kind in which a pile of sheets is elevated by primary and secondary means to separating devices, the elevation of the pile being effected initially by the primary means and the pile then being transferred to the secondary means which continues the elevation so that the primary means may be lowered to take a fresh pile and a substantially continuous supply of sheets made available to the separating devices, the primary elevating chains or the like are outside the secondary elevating chains or the like as seen from the side of the machine. In the form of Fig. 1, the primary elevating means comprise a pair of chains 5, 6 at each side of the pile 1 passed over sprockets 9, 10 mounted on a shaft 3. One end of each chain is connected to a bar 11 extending in the fore and aft direction and adapted to support a pile board 12 and the other end of the chain is connected to a counterbalance weight 13 serving to keep the chain on the sprocket. The shafts 3 on each side of the pile are driven at the same speed by a shaft 20 carrying worms 21 at each end to engage gears 18 on shafts 3. The secondary elevating means comprise chains 7, 8 on each side passing over sprockets 14, 15 mounted on a sleeve 4 surrounding shaft 3 and driven in like manner by a shaft 22. Chains 7, 8 are connected to a bar 16. The pile is positioned in the forward direction by front gauges 25 which are rearward of the primary and secondary chains 6, 8. The shafts 20, 22 are driven by means not described, controlled to maintain the top of the pi!e adjacent the conveyer 2. In operation a pile on a board 12 is placed on the bars 11 of the primary elevating means and lifted towards the separating devices until the secondary bars 16 can be swung under the edges of the board 12 and lifting continued by the secondary means. Meanwhile the primary chains 5, 6 are lowered, a new pile placed on a board 12a on the bars 11 and lifted thereby until it supports the board 12 carrying the first pile so that the secondary chains can be lowered. When the first pile is nearly exhausted the board 12 is withdrawn manually and the remaining sheets allowed to fall onto the second pile. To assist withdrawal of the pile board sheet strips of smooth material, e.g. flexible plastic material may be placed between the board and the pile it supports. When the board 12a reaches a certain level the secondary bars 1'6 are engaged under the edges thereof to continue the elevation and the primary bars 11 lowered to receive a third pile and so on. The primary and secondary chains on both sides of the pile are outside the position which would be occupied by a pile of maximum width for which the machine is constructed. In another form the secondary cross bars f6 are transverse instead of longitudinal of the machine and the piles are carried on a series of longitudinal slats on a primary pile table. When the pile reaches the predetermined height the scondary cross bars are engaged under the projecting ends of the slats to continue lifting while the primary pile table is lowered to receive a second pile. The slats are withdrawn rearwardly when the pile they support is nearly exhausted. In Fig. 4, the primary support bars 11 carry cross bars 31 on which rests a pile board 48. The secondary chains 7, 8 carry cross bars 40, 41 to which are pivoted pawls 42, 43 adapted to be displaced and fall in under the edges of the pile board 48 when this reaches a certain level so that the lifting may be taken over by the secondary means. The pile board may be divided longitudinally so that the two halves can be withdrawn sideways. The cross bar 40 is guided by vertical strips 44 and the bar 41 slides in slots 45 in guide strips 46. As before the forward cross bar 41 is located forward of the front gauges 25, the pawls 43 projecting rearwardly between the gauge 25 to engage the pile board 48. A horizontal flap 26 mounted above the front gauges 25 leads the front edge of the sheet to the conveyer and corrects any displacement of the remaining sheets by moving against the pile. Specifications 518,804, 595,921, 595,922 and 605,424 are referred to.