Patent GB-1251991-A (GB)
IPC: B65H29/00
Filed: 1968-08-23
Abstract: 1,251,991. Stacking devices; conveyers. KOPPERS CO. Inc. 23 Aug., 1968 [11 Sept., 1967], No. 40530/68. Headings B8A and B8C. In an apparatus for piling stacks of blanks from a corrugated blank forming machine into large piles, the stacks are fed by conveyors 24 and 26 from the discharge device of said machine to an inverting device 22 having a substantially vertically inclined guide down which the stacks slide. Whilst on the guide, each alternate stack B is engaged by a lever 92 and pivoted about its leading edge into a " face-down " position on a take-off conveyer 90 and each other stack A is engaged by fingers carried by the take-off conveyer and pivoted about its trailing edge into a " face-up " position on the take-off conveyer. The stacks thus oriented are fed to belts 240 of conveyer 138 which in turn feed them to a stacking device comprising a vertically reciprocable lifting conveyer 242 and supporting plates 308, 310 reciprocable into and out of a position below the stacks. When the stack has reached the desired height it is transferred by the lifting conveyer to an unloading device 250. In the embodiment illustrated in Figs. 2 and 3 stacks of half the maximum width are stacked whereas in another embodiment involving the withdrawal of certain of the fingers of conveyer 90, stacks of maximum width can be stacked. Furthermore, suitable adjustment of the machine also enables the stacks to be stacked all " face-up " or all " face-down ". The discharging device (see Fig. 4) from the blank forming machine comprises belts 12 over which pairs of superimposed blanks C, D are fed, the blanks in each pair being relatively skewed. The blanks are stacked into stacks A and B on a transversely running roller conveyer 10, by a gate 14, the conveyer 10 being actuated to feed the stacks to conveyer 20 when the stacks have reached the desired height. Conveyer 20 (see Fig. 2) comprises free-wheeling rollers 30a which are driven at the appropriate points in the cycle by a belt 32 reciprocated into and out of contact with the rollers by a bar 50 actuated by piston operated levers 54. Conveyer 26 (see Fig. 2) consists of conventionally intermittently driven belts 62, during the driving period of which stacks are fed into the inverting device. As each leading stack pivots over the edge of the belts into the guide of the inverting device any interengagement of the blanks between it and the next stack is broken by the upward movement of the rear end of the stack. The inverting device (see Figs. 2 and 8) not only functions to vertically orientate the stacks ready for " face-up " or "face-down " orientation but also functions to laterally off-set each alternate stack. The device comprises a pair of side guides 100, 102, which engage the lateral edges of the stacks and which can be moved laterally in unison to effect the offsetting, the " face-down " orienting lever 92 being reciprocably pivoted between the guides. The guides, each of which comprise angle strips 104, 106, are mounted upon blocks 108, 110. Block 110 is secured to rods 112 slidable through supporting brackets 114a, 114b fixed to the apparatus frame and is reciprocated laterally by a piston and cylinder device 116 interposed between itself and the bracket 114b. The block 108 is slidable over the rods and is connected by a piston and cylinder device 122 to a block 118 clampable at a desired position along the rods. In use the block 118 is clamped at the desired position along the rods to accommodate a stack of the desired size and the device 122 is actuated to move block 108 to the position shown in phantom lines in the right hand part of Fig. 8. After a stack A has been fed between the guides the block 108 is moved by device 122 so that the stack is engaged by the guides and is thus moved slightly to the right relative to their direction of movement. Block 108 is then reforwarded to release stack A which is then oriented by finger 96. Stack B is then fed to the guides and device 122 actuated to move guide 100 into contact with the stack and the device 116 is simultaneously operated to move the guide/blocks/rod assembly to the position shown in phantom lines in the left hand side of Fig. 8. In this way stack B is offset slightly to the left relative to the direction of feed of the stacks to the device. Finally guide 100 is withdrawn, the freed stack pivoted by lever 92, and the guide/blocks/rod assembly moved back to its original position for another cycle. The conveyer 90 (see Figs. 2, 11) consists of a series of parallel inclined flat supports 142 up which the stacks from the inverting device are pushed by fingers carried by chains 174 located between pairs of supports. Each chain carries four different types of fingers (see Fig. 9a, not shown) some, (94 and 184) of which are permanently operative in order to engage maximum size stacks and others (96 and 186) of which are retractable to and from a stack engaging operative position for use, in conjunction with the permanently operative fingers, with stacks of less than maximum size. In the preferred embodiment, the chains carry in sequence (see Fig. 11) a roller topped retractable finger 96, a permanent non-roller topped finger 94, a retractable non-roller topped finger 186, a second finger 96, a second finger 94, and a roller topped permanent finger 184. When dealing with half width stacks all fingers are operative and a first stack A location in the inverting device is engaged at its lower edge first by finger 96 to effect the face up orientation and is then pushed up conveyer 90 by next finger 94. Subsequently stack B is oriented face down by lever 92 and is pushed up conveyer 90 by finger 186 after which the stack C is oriented face-up by second finger 96 and pushed up conveyer 90 by second finger 94. Finally, stack D is oriented by lever 92 facedown and is pushed up conveyer 90 by finger 184. For use with maximum size stacks, the two fingers 96 and the finger 186 are withdrawn leaving both fingers 94 and finger 184 operative. Finger 184 effects the face-up orientation of a stack which is pushed along conveyer 90 by the first following finger 94 and the next stack is pivoted by lever 92 to the face-down position and is pushed up conveyer 90 by the second following finger 94 after which 184 operates on the next stack. The retractable fingers are forwarded to their operative positions by raising bars 212 over which rollers, carried by the fingers, run to pivot the fingers to the upright operative positions. The stacking device comprises an intermittently driven band conveyer 262 vertically reciprocable by means linkage 302, 300 and 298 and a pair plates 308 and 310 horizontally reciprocable into a position under the stack by piston operated bell cranks 348. In operation a stack is fed on to the lowered conveyer 262 into engagement with a stop 276 after which the conveyer is raised. During the raising of the conveyer the plates 308 and 310 are retracted to drop any stack carried thereby on to the one carried by conveyer 262. When the conveyer has been fully raised the plates are forwarded under the lowest, added, stack and the conveyer lowered to receive another stack. When the stack has reached a height determined by switch 248 the conveyer 262 in its upper position is actuated to feed the large stack over roller 390 to unloading device 250. Accurate location of each stack on conveyer 262 against stop 276 is ensured by a set of piston operated pusher fingers which engage the rear end of the stack (see Fig. 10, not shown).