Patent GB-915247-A (GB)
Title: Automatic sheet or strip stacker
Inventor: HEARTSTEDT OTTO EDMUND
IPC: B65H31/32
Filed: 1960-07-01
Abstract: 915,247. Delivering sheets. CONTINENTAL CAN CO. Inc. July 1, 1960, No. 23133/60. Class 100 (1). Flexible metal sheets 23 are delivered from a cutting or other machine to a stacking enclosure 20 by a conveyer 11 consisting of parallel, spaced endless belts 12. The enclosure 20 is generally rectangular in cross-section, being bounded at the end near the conveyer by fixed vertical posts 25 and at the opposite end by vertical arms 27. The arms 27 have horizontal base portions 28 which are mounted on a shaft 30 carried by the machine frame. Sleeves 33, Fig. 2, secured to the shaft 30, have a plate 34 mounted thereon which plate supports a stack 35 of sheets 23. The sides of the enclosure 20 are formed by flexible metallic tapes 52 secured to the machine frame at their top and bottom ends and having middle portions which are urged inwards in relation to the enclosure by metal bands 54 bent into tear-drop shape. The bands 54 are pivoted at 55 to vertical members 56 and, because they tend to hang centrally in relation to their pivot points, urge the tapes 52 inwards. As each sheet 23 leaves the conveyer 11 its leading edge strikes a plate 24 carried by a cross-beam 22 at the top of the enclosure 20 and its side edges engage inclined rails 21 also mounted at the top of the enclosure. As the middle portion of the sheet is unsupported it sags until the side edges slide off the rails 21 and the sheet falls in a bowed condition so as to help form the stack 35 on the plate 34. As the sheet falls down the enclosure 20 it is kept in a bowed condition by the engagement of the side edges of the sheet with the tapes 52, the bowing of the sheet preventing inversion or tipping thereof during its downward movement. When a pile of sufficient size has accumulated in the enclosure 20 it is transferred to a pallet 45 comprising three spaced, parallel ramps 48 supported on a frame carrying wheels 44. The wheels 44 run on rails 42 and the pallet 45 is movable along the rails by means of a pneumatic cylinder 50 between the position shown in Fig. 1 and a position closely adjacent to the enclosure 20. When the pallet is in the latter position the shaft 30 is rotated in an anticlockwise direction (Fig. 1), by means of a reversible electric motor, until the arms 27 pass between the ramps 45 and deposit the pile of sheets thereon; the pallet is then moved to its Fig. 1 position, where it may be either unloaded or replaced by an empty pallet, and the shaft 30 is rotated in a clockwise direction to restore the arms 27 to their vertical position. During removal of a pile from the enclosure 20 sheets delivered from the conveyer 11 are supported near the top of the enclosure by three pairs of horizontal pins 59, 60, 61. Each pair comprises oppositelypositioned, reciprocating pins 62, Fig. 6, each slidably supported in sleeves 67, 68 mounted on the machine frame. Shafts 63, 64 mounted above the pairs of pins each carry three arms 69 having furcated lower ends which engage between abutments 65 on the pins 62. The shafts 63, 64 are simultaneously rotated in opposite directions by means of rack-and-pinion mechanism operated by a pneumatic cylinder, such rotation causing the pins to project into or be withdrawn from the enclosure 20. The pins are projected into the enclosure, as shown in Fig. 6, before the arms 27 are swung outwards to transfer the pile in the enclosure. After transfer of the pile to the pallet and restoration to vertical position of the arms 27 the pins are withdrawn from the enclosure and the sheets which have accumulated thereon fall down to rest on the plate 34. As shown in Fig. 2, the pair of pins 60 is in a lower plane than the other two pairs so as to keep the sheets in their bowed condition.