Para, Emanuele (Via Capezzana 20, Carmignano, I-59015, IT)
| 1. | Equipment for palletizing packs of flat sheets of paper, cardboard and the like, characterized by the fact of including at least one first station for the formation of portions of a stack by placing each layer of the portion of the stack being formed on top of the preceding layer, and a second station cooperating with said first station for the completion of the stack by means of stacking the previously formed portions of stack by insertion of each portion underneath the preceding one. |
| 2. | Equipment according to claim 1, characterized by the fact of providing means for infeed of a pallet to said first station and for forming a portion of a stack on top of said pallet. |
| 3. | Equipment according to claim I or 2, characterized by the fact that said first and second stations are adjacent. |
| 4. | Equipment according to one of the preceding claims, characterized by the fact that said first station includes: a motordriven roller conveyor located in a position moderately raised above the floor for the placement of individual packs to be used to form the layers of the stack being formed, means suitable for transferring each pack laterally off the roller conveyor onto an adjacent structure, vertically mobile in both directions and equipped with a further motordriven roller conveyor, each portion of the stack being obtained by gradually lowering this mobile structured from a raised position so as to enable succeeding layers to be stacked on top of one another. |
| 5. | 5* Equipment according to claim 4, characterized by the fact that said means for transferring each pack include a plurality of rods on the same plane as the supporting roller conveyor and gliding towards the outside of it above the vertically mobile structure, and a thrust bar, mobile in the same direction as the rods and oscillating from a vertical position on its forward run to a horizontal position on its return run, so as not to interfere with infeed of the succeeding pack on the supporting roller conveyor. |
| 6. | Equipment according to claim 4 or 5, characterized by the fact that said means of transfer of each pack operate at right angles to the direction of infeed of the pack on the supporting roller conveyor, and that a reed element, driven pneumatically and not interfering with the rods and bar, is provided to hold the layer after it is transferred to the vertically mobile structure, while permitting the rods and bar to withdraw. |
| 7. | Equipment according to one of the preceding claims, characterized by the fact that said second station includes a motordriven roller conveyor, a first horizontally mobile containing wall element and a vertically mobile member bearing a device with horizontally mobile forks and a second containing wall elementhorizontally mobile with respect to the memeberequipped at the bottom with a grating that permits the passage of the forks. |
| 8. | Equipment according to claim 7, characterized by the fact that each portion of the stack, when it reaches the roller conveyor installed on the second station, is lifted by the forks and placed on top of the next stack, the arrival of a palletized portion of the stack determining its completion and palletizing. |
| 9. | Equipment according to claim 1, characterized by the fact of combining several parallel devices for the formation of portions of stacks with layers of one or more adjacent packs, which portions of stacks may also be palletized, means for the recovery and distribution of the portions of stacks formed and one or more stations for the completion of the palletized or nonpalletized stacks. |
| 10. | Equipment according to claim 1, characterized by the fact of combining several parallel devices for the formation of nonpalletized stacks with layers of one or more adjacent packs, means for the recovery and distribution of the portions of stacks formed and one or more stations for the completion and possible palletizing of the stack. |
| 11. | Equipment according to claim 9 or 10, characterized by the fact that the said means for recovery and distribution of the portions of formed stacks consist of an automatic cart for movement or platforms or exchangers or similar means of transportation. |
Background Art At the present time, to form stack of sheets of paper or cardboard, the equipment used stacks layers or packs of products supplied one after another on a surface that descends gradually from a preset height over the work surface, which is normally placed about 100 cm from the ground. Devices of this type obviously require an elevator or conveyor belt and are therefore bulky and complex. In addition, the height of the stack is limited by the height of the infeed.
Alternatively, similar devices to those described above are housed in a pit in the floor.
The height of the stack is obviously limited by the depth of the pit which, in addition, must be sufficiently large to permit removal of the stack without interfering with the formation of the next stack. All of this places serious limitations on the flexibility of the plant in which the equipment is installed. In addition, the presence of the pit causes further risks of accidents for the operators and may not be compatible with antiseismic regulations.
Disclosure of Invention The object of this invention is therefore to provide a stacking and palletizing machine that is free of the limitations and inconveniences described above.
This object is achieved with a device in conformity with the enclosed claims, comprising substantially at least two cooperating stations, in the first of which a portion of a stack is formed, and may also be palletized (that is, placed on a pallet), by stacking each layer on top of the preceding layer, while in the second station the stack is completed by joining the portions of the stack previously formed by inserting each portion underneath the
preceding one. Palletizing is completed by inserting, underneath the stacked portions, a palletized portion or simply a pallet.
In one form of implementation of the invention, several stations form portions of a stack, which may also be palletized, operating in parallel with each other and supplying one or more completing stations or one or more palletizing stations.
The technical features and advantages of this invention will be clarified by the detailed description that follows of a number of non-limiting examples of its implementation.
Brief Description of Drawings In the drawings: - Fig. 1 is a schematic illustration from above of an equipment in conformity with the invention; - Fig. 2 is a lateral view according to II-II of Fig. 1 ; - Fig. 3 is a partial view from line III-III of Fig. 1 ; - Fig. 4 is a partial view from line IV-IV of Fig. 1 ; - Fig. 5A to 5P provide a schematic illustration of the steps in a possible operating sequence in a view similar to that of Fig. 2 ; - Fig. 6A to 6M provide a schematic illustration of the stages relative to the partial formation of a stack and the insertion of a pallet under it, in a view similar to that of Fig. 3; -Fig. 7A to 7G provide a schematic illustration of the stages relative to the completion of a stack and the insertion of a pallet under it in a view similar to that of Fig. 4 ; - Fig. 8 and 9 are a schematic illustration of the layout of two further ways of implementing the invention.
Modes for Carrying Out the Invention With reference to Fig. 1 through 4, an equipmnet 1 in conformity with the invention comprises substantially a first station 10 for the formation of a portion of a stack 12 of flat sheets of paper or cardboard and the possible insertion underneath of a pallet 14, and a second adjacent station 50 for the formation of the final palletized stack 52.
More in particular, the first station 10 includes a roller conveyor 16 with motor-driven rollers supporting the individual packs 18 which will form the layers of the finished
stack (in the example illustrated, each layer is made up of a pack or bundle of die-cut cardboard boxes and has therefore been indicated with the same numerical reference 18).
The packs 18 are supplied, for example, by a motor-driven roller conveyor 20 which may also be equipped with a device 21 for rotating the pack 18 around a vertical axis.
This roller conveyor 16 is installed in a raised position with respect to the floor, for example at a height of 80-100 cm, naturally accessible to the operator, and is equipped with a wall element 13 for the alignment of the individual packs 18 in the crosswise direction with respect to the infeed direction. There are also means for moving the pack 18 sideways off the roller conveyor 16 onto an adjacent motor-driven roller conveyor 22 mounted on a structure 24, which is vertically mobile in both directions. In the example illustrated the transfer of the individual pack 18 is obtained by means of a plurality of rods 17 and a thrust bar 19. The rods 17 are on the same level as the roller conveyor 16 and glide towards the outside of it above the vertically mobile structure 24. The bar 19 is mobile in the same direction as the rods 17 and oscillates from a vertical thrusting position in its forward run to a horizontal position for the return run, so as not to interfere with the next pack 18 supplied to the roller conveyor 16. Advantageously, the means for transferring the pack 18 operate at right angles to the direction of infeed on the roller conveyor 16. Also, a reed element 11, driven pneumatically and not interfering with the rods 17 and the bar 19, is provided to hold the layer 18 once it has been transferred to the structure 24 and permit the rods 17 and the bar 19 to withdraw at the same time.
As illustrated more in detail in Fig. 6A through 6F, the structure 24, bearing the roller conveyor 22, descends gradually fro a raised position so as to permit succeeding layers 18 to be stacked. In this way a portion of a stack 12 is obtained and transferred to the adjacent second station 50, while the structure 24 ascends to receive a new layer 18 on its roller conveyor 22 and start a new cycle of formation of a portion of a stack 12.
The roller conveyor 22 can also receive a base or pallet 14 coming, for example, from another roller conveyor 26. In this way, positioning the pallet 14 on the roller conveyor 22 at the beginning of the cycle of formation of a portion of the stack 12, the portion obtained will be palletized 12' (see also Fig. 6G-6M).
The second station 50 is illustrated in greater detail in Fig. 4. It comprises essentially a motor-driven roller conveyor 54, a first horizontally mobile containing wall 55 and a vertically mobile member 56 holding a forked device 57 which is horizontally mobile, and a second containing wall 58-which is horizontally mobile with respect to the member 56-equipped at the bottom with a grating 59 that permits passage of the forks 57.
Each portion of the stack 12, when it reaches the roller conveyor 54, is lifted by the forks 57 and then placed on top of the next portion of the stack 12 (see also Fig. 7A-7C). The arrival of a portion of a stack on a pallet 14 (palletized portion 12') determines completion of the stack 52 and of palletizing (see also Fig. 7D-7E). It is obvious that the second station 50 permits placing a stack 52, formed by layering the portions of the stack 12 in the manner indicated above, directly on a pallet 14 as indicated in Fig. 7F- 7G.
Correct lateral alignment of the portions of the stack 12 is ensured by the wall elements 55,58. In particular wall element 58 and the grating underneath it 59 permit withdrawal of the forks 57 without causing any movement of the layers of the stack (see also Fig. 4).
A possible complete cycle of formation of a stack 52 on a pallet 14 is schematically illustrated in Fig. 5A-5P.
To better exploit an equipment in conformity with the invention, it may be practical to install several machines parallel 100,101, 102 to form portions of stacks 120, 121, 122, with layers of one or more adjacent packs 180, 181, 182, which portions of stacks may also be palletized. The portions of stacks 120,121, 122 are then transferred to a station 500 which completes the palletized stack 520, in the manner described above, by means of an automatic cart 200 for moving it, or any other known system of recovery and distribution (see also Fig. 8).
Also, it is possible to prepare parallel partial stacks 123, 124, 125 not palletized, and use an automatic cart 200 or equivalent mechanism, to complete formation of the stack and palletize it by means of a device 600 that serves to double and palletize it, for example as described in WO 02/083528, possibly preceded by a compacting device 700 (see also Fig. 9).
A machine in conformity with the invention has numerous advantages. In the first place, the two stations of which the machine is composed are relatively simple to construct, occupy a limited space (on the order of 2X2 m each for stack formation using flat sheets measuring up to 1. 8X1. 6 m) and can easily be added to existing processing lines. In the second place the equipment can be sized according to production and/or investment needs and can be added to over time with further units for the parallel formation of stacks. The equipment is readily accessible by an operator because all the operations take place at heights a few dozen centimeters off the floor. Production efficiency is particularly high as there is no down time in stack formation. In the third place, the stack can theoretically be any height whatsoever, without limitations given by the equipment, the only limitations being given by the need for stability.
The invention thus conceived is susceptible to several modifications and variants, all falling within the scope of the inventive idea. Furthermore, all the details can be substituted with technically equivalent elements.