WO2009122312A1

WO2009122312A1 - A plant for stacking pallets.

Info

Publication number: WO2009122312A1
Application number: PCT/IB2009/050581
Authority: WO
Inventors: Franco Stefani; Ennio Di Bernardo
Original assignee: System S.P.A.
Priority date: 2008-03-31
Filing date: 2009-02-12
Publication date: 2009-10-08
Also published as: ITMO20080094A1

Abstract

A plant for pallet-stacking, comprising: an unstacking device (2) for removing single items (C) making up a pallet; a stacking device (4) for receiving single items (C) which make up an order to be stacked on a pallet; an automatic store (3), comprising a plurality of shelves or trays (30) predisposed to contain ordered rows of items (C); the shelves or trays (30) being stockable internally of the automatic store (3) and being commandably transferable between a loading position or station, in which the shelves of trays (30) receive the items (C) coming from the unstacking device (2), and an unloading position or station, in which the items (C) are supplied to the stacking device (4). The automatic store (3) is predisposed to identify the items (C) and/or the position of the items (C) on the shelves or trays (30) in the automatic store in order to enable a selection of the items (C) to be placed in outlet according to an order.

Description

A plant for stacking pallets.

Description.

In the sector of logistics and the management of orders and dispatch of products, it is now a consolidated requirement to handle and manage pallets made up of items of products which are not homogeneous. To make up a pallet constituted by items which are not the same, it is necessary to perform partial collections from various pallets composed of homogeneous items or articles. For example, to make up a pallet of a certain number of products which are different from each other, which for the sake of simplicity can be called A, B, C, D..., it is necessary to remove the required quantity of products A from the pallet bearing products A, the required quantity of products B from pallet B, and so on.

At present there exist two main method for managing the composition of pallets of non-homogeneous products.

A first method, known sectorially as Man to Goods, comprises arranging the pallets of homogeneous products internally of a manual store. The removal of the single products and the composition of the non-homogeneous pallets are carried out by special operatives who move internally of the store using lift trucks or other vehicles. The operatives perform partial collection from the homogeneous pallets and compose the non-homogeneous pallets. This first method, in the case of particularly numerous orders, requires one or more operatives working simultaneously, or a more laborious operation as once the pallets have been made up the operative has to return to the deposit point of the client's pallets to collect an empty pallet on which he can continue to make up the order. Management of these operations is slow and expensive. A second method, known in the sector as Goods to Man, includes the use of stores provided with movement devices which bring the homogeneous pallets to an operator, who collects the requested articles and makes up the non- homogeneous pallets. This second management method, by preventing the displacement times of the operatives in the store, enables the manageable number of articles to be increased per unit of time, thus improving productivity with respect to the first described method.

The first method, the productivity of which can be increased by increasing the number of operatives, however exhibits a limit constituted by the availability of space that can be dedicated to the store. The less available space there is, the smaller is the number of operatives who can be used, and the lower is the productivity of this managing method.

The second managing method exhibits a limit constituted by the maximum productivity of the operative, in particular in reference to the arrangement of the products on the pallet and the time used to pass from one pallet to the following pallet.

Both the methods of management thus exhibit limits of productivity which are hard to overcome.

To overcome these limits in the managing methods of known type, a managing method has recently been developed which includes realising stores in which the homogeneous pallets are not contained; rather there are the various articles in the stores, removed from the homogeneous pallets. For the composing of non-homogeneous pallets, the single articles are collected from the magazine, singly, by means of collecting and transporting devices, and conveyed to a composition station of non-homogeneous pallets. For removing and transporting the single articles fast tracker cranes can be used which, in order to move different types of articles, use trays loaded and unloaded by automatic systems. This solution has a considerable number of drawbacks as it requires large spaces and high costs of realisation. An alternative solution to tracker cranes can be predisposing stores constituted by a series of storage channels realised using non-motorised gravity-driven roller planes with a motorised final tract, of such a length as to receive the greatest possible number of articles. The channels are distributed on several planes with the aim of better exploiting the height of the available space.

The various articles are collected from the storage channels, in the quantities requested, and are conveyed to the non-homogeneous pallet preparation zone. To fill the storage channels, both automatic and non-automatic stores are used, in which an automatic system collects the articles required from the homogeneous pallets. The articles are singly collected and sent on to the storage channels with the correct orientation.

This solution exhibits the drawback of being expensive, especially when the number of articles managed exceeds 350-400. A further drawback is the higher maintenance cost, as the operations are made rather difficult by the fact that there is little free space between the different levels of the storage channels.

The main aim of the present invention is to provide a plant and a method for making up pallets which obviates the drawbacks in the known-type plants and methods.

Characteristics and further advantages of the invention will better emerge from the detailed description of an embodiment of the invention, made with reference to the figures of the drawings, which are provided by way of non- limiting example, and in which: figure 1 shows a schematic plant view; figure 2 shows a schematic view from below of figure 1; figure 3 is a schematic partial view from above of figure 1 ; figure 4 is a schematic section made along section line IV-IV of figure 2; figure 5 is a perspective view of a detail (tray) housed in the entry loading station 9, frontally illustrated in figure 2.

The plant of the present invention comprises an unstacking device 2 predisposed to remove the single homogeneous items C making up the pallet from the pallet itself. The unstacking device 2 has only schematically been illustrated in figure 1 as it is a known device in the sector. It receives a pallet in entry, stacked with a certain number of items C, and removes the items C or only a single item according to needs from the pallet, and arranges the item or items on a first transport device 5.

The first conveyor device 5 is predisposed to supply the items C taken from the unstacking device 2 to an automatic store 3 of a substantially known type, at least in its basic construction.

The automatic store 3 in particular comprises a plurality of trays 30 predisposed to contain ordered rows of items C.

The planes or trays 30 can be stocked inside the automatic store 3 and are on command transferable in entry into an entry station 9 or a loading position, in which they receive the items C coming from the unstacking device 2, and in outlet at least to an outlet station 10 or unloading position, in which the items

C are supplied to a stacking device 4. The stacking device 4 is predisposed to receive single items C and to stack them on a pallet. The stacking device 4 too has only been illustrated schematically as it is a known device. A second conveyor device 6 supplies the items C from the automatic store 3 to the stacking device 4. Note that while the items C coming from the unstacking device 2 are normally homogeneous, the items which will be used to make up the pallet on the stacking device 4 are not normally homogeneous, but are constituted by different items (heterogeneous), the composition of which (assembly) corresponds to the order being made up.

The automatic store 3 is substantially of known type and is predisposed to receive items C in entry and to enable selection of those, from among these and also from among all items previously identified and stocked, to be arranged in outlet. The identifying data of each item C is sent to a processor which associates to each identified item C the position which it occupies on the tray on which it is housed as well as the position of the tray internally of the store, and stores the data in a memory. Thus the position of the item C is defined by two distinct data: the position of the item C on the tray 30 and the position of the tray 30 in the automatic store 3.

Inside the automatic store 3, the trays 30 are stocked on shelves superposingly arranged in columns. The movement of the trays is done by a vector 7 which is mobile at least along a vertical direction internally of the store itself. The vector 7 is in turn provided with a transfer organ predisposed for collecting the trays 30 from shelves and for replacing them on the shelves, comprising at least a station or an entry position 9 of the items C and at least a station or outlet position 10 of the items C.

The vector 7 is mobile internally of the store between the various positions of the trays 30, the station or entry position 9 and the at least a station or outlet position 10 of the items C from the automatic store 3. The function of the vector 7 is essentially the typical role of a vectors in an automatic store. In the example the vector 7 removes a tray 30 from the shelf of the automatic store in which it is stocked and brings it to the entry loading station 9 or the outlet unloading station 10, or transfers a tray 30 from one of the two stations to a shelf where the tray 30 has been stocked.

The entry loading station 9 and outlet unloading station 10 are preferably arranged, but not compulsorily, on opposite sides of the automatic store at special openings afforded in the opposite walls of the store. In a preferred embodiment the automatic store 3 comprises a plurality of trays 30 predisposed to contain ordered rows of items C (stockable internally of the automatic store 3 and transferable on command between a loading position in entry, in which they receive the items C, and at least an unloading position, in outlet, from which the items C are supplied to the stacking device) which are associated with means for orderedly positioning the single items C in at least a row for each tray 30. In the illustrated embodiment there are two rows, but there might be more according to needs and requirements. In particular the means comprise parallel slits 12 on the bottom of the trays 30 internally of which, at the loading and unloading stations or positions of the automatic store 3, transport belts 19 and 20 can be respectively inserted on command, which transport belts 19 and 20, from an inactive lower position, at which they do not interfere with the bottom of the shelves or trays 30, are raisable on command into an active position at which they superiorly project from the slits and come into contact with the items C which make up the row such as to raise them from resting on the bottom of the trays 30. The transport belts 19, 20 are activatable on command with a coordinated action with the first conveyor device 5 and with the second conveyor device 6. In the illustrated embodiment two loading stations or positions 10 are included, and are exactly superposed, which are alternatively and directly connectable to the second conveyor device 6 by means of an orientable connecting transporter 11. In this way, while one of the two unloading stations 10 works by operating the transfer of the items C from the tray to the second conveyor device 6, the other, in order to cut operating times, can contemporaneously be loaded with a second tray, once more moved by the vector 7, on which the rows, or row, of items C are housed, which items C are destined to be unloaded as soon as the unloading first under way has been completed. Each tray 30 is predisposed to house two parallel rows of items C. In the usual and preferred, though not exclusive, functioning of the invention, following an order sent to the system to make up a pallet with predetermined quantities of heterogeneous items C, the pallets of the various types of items C (homogeneous for each pallet) are first unloaded into the unstacking devices 2 and sent to the automatic store 3. In particular the items C are supplied to the automatic store 3 in ordered and compact rows. To this end the first conveyor device 5 comprises a compacting device 5 a predisposed to near the items C to one another in an ordered row. The compactor device 5 is preferably though not exclusively constituted by a roller plane the rollers of which progressively slow down the items C such as to near them to one another and form a complete row which is then transferred onto the tray 30 by means of the belts 19.

Note that - and this is also true for the unloading station 10 - among the various operating possibilities available, the following are comprised: the forming of complete rows of homogeneous items C or the formation of complete rows of heterogeneous items C or even the forming of incomplete rows of homogeneous items C or heterogeneous items C. In more detail the modalities of use of the trays can be: a homogeneous tray made up of one or more rows of a same product; a non-homogeneous tray composed of several rows of items C which in each row are homogeneous but which are heterogeneous with respect to one another; a non-homogeneous tray made up of rows at least one of which contains products which are non-homogeneous (typically used to compose rows in a same order); a non-homogeneous tray composed of incomplete rows (which may be single items).

The tray 30, once loaded with the desired rows of items (two, three or more) is moved and stocked internally of the automatic store 3 by the vector 7 in the typical way in automatic stores, up to the moment of its use during the stage of unloading for sending the items C contained therein (or part of the items C) to the stacking device 4. During this stage the tray 30 is collected from the shelf on which it is stocked and is moved and brought by the vector 7 into the unloading station 10.

As they exit from the automatic store 3, i.e. with the tray in the unloading station 10 during a stage of collection of the items C by the belts 20, the items

C are usefully and preferably distanced from one another. In order to obtain the distancing between the items C, the second conveyor device 6 comprises a separator device 6a (positioned immediately at the exit of the tray) predisposed to distance and count the items C of an ordered row exiting the automatic store 3. The separator device 6a can be constituted by a usual

"accelerator" device, for example a roller plane in which the rollers progressively accelerate in a distancing direction from the automatic store 3 such as to distance the single item C transiting thereon from the other items C which follow the first item C in the row on the trays 30. In other possible embodiments of the invention, instead of the transport belts 19 and 20 there might be other means for enabling ordered positioning, and collection during unloading of the single items C in at least a row for each tray constituted, for example, by pusher systems operating above the loading station 9 and the unloading station 10 and the conveyor devices 5 and 6. To sum up, during normal operation, the items C coming from the unstacking device 2 are directed onto the first conveyor device 5 where, in a preferred embodiment, they are compacted to form a row which is then transferred as a row onto a tray 30 located on the loading station 9. When both parallel rows are predisposed on the tray 30 (or in any case all the rows making up the tray 30), the tray 30 is transferred internally of the automatic store 3 and stocked on a predetermined shelf therein.

As soon as the order is received to make up a pallet composed of predetermined numbers of heterogeneous items C, the trays 30 containing the heterogeneous items C are identified and collection is automatically commenced, following typical functioning modes of the automatic store. This enables the tray containing the items C to be collected in at least one of its rows to be brought into the single unloading station 10. The collection, from the single row, of the exact number of homogeneous items C is performed by the transport belts 20 which, with the aid of the orientable connecting transporter 11, send the items C onto the second conveyor device 6. The items C are immediately separated and distanced directly at the outlet by the separator device 6a predisposed for distancing the items C of an ordered row from one another on exiting the automatic store 3. The items C thus distanced are then directed, in the desired order, to the stacking device 4 where the formation of the pallet corresponding to the order is done. The device, completely automated, is extremely compact with respect to the prior art, and is characterised by considerable elasticity. It enables orders to be made up very rapidly and is easy to integrate with several unloading and loading lines.

The illustrated plant is an embodiment of a method which can be schematically illustrated as follows.

On receiving the order to make up a pallet of items C which are heterogeneous, the method includes the following, in order: removing single items C, in a predetermined number, from a pallet of items C which are homogeneous (the operation must be performed for each type of pallet); identifying the various items C; arranging the items in determined positions internally of an automatic store 3; removing a predetermined number of items C from the automatic store 3; making up a pallet with the predetermined items C which items C correspond to the given order.

The stage of identifying the items C further comprises the stage of assigning to each item C a datum relating to a determined position thereof internally of the automatic store 3.

The means for identifying the items C and/or the position thereof on the trays in the automatic store 3 in order that it is possible to select those which from among them and all those previously identified and stocked to be placed in outlet according to the order to be made up are easily identifiable in the prior art. The identifying data of each item C are sent to a processor which associates to the single item C identified the position occupied thereby on the tray on which it is housed as well as the position of the tray internally of the store 3. This enables the items C to be moved in an orderly fashion.

Claims

Claims.

1). A plant for pallet-stacking, characterised in that it comprises: an unstacking device (2) for removing single items (C) making up a pallet from the said pallet; a stacking device (4) for receiving single items (C) which make up an order to be stacked on a pallet; an automatic store (3), comprising a plurality of shelves or trays (30) predisposed to contain ordered rows of items (C); the shelves or trays (30) being stockable internally of the automatic store (3) and being commandably transferable in entry between a loading position or station, in which the shelves or trays (30) receive the items (C) coming from the unstacking device (2), and in outlet at least at an unloading position or station, in which the items (C) are supplied to the stacking device (4); means for identifying the items (C) and/or a position thereof on the trays in the automatic store (3) being included to enable selection of items (C) from among the items (C) and from among all the items (C) previously identified and stocked to be placed in outlet according to an order to be made up; identifying data of each item (C) being sent on to a processor which associates to each identified item (C) a position occupied thereby as well as a position of the tray (30) internally of the automatic store (3). 2). The plant of claim 1, comprising a first conveyor device (5) predisposed to supply the items (C) from the unstacking device (2) to the automatic store (3). 3). The plant of claim 2, wherein the first conveyor device (5) comprises a compacting device (5 a) predisposed to near the items (C) to one another in an ordered row thereof.

4). The plant of one of the preceding claims, comprising a second conveyor device (6) predisposed to collect the items (C) from the automatic store (3) and to supply the items (C) to the stacking device (4). 5). The plant of claim 4, wherein the second conveyor device (6) comprises a separator device (6a) predisposed to distance from one another the items (C) of an ordered row in outlet from the automatic store (3). 6). The plant of one of the preceding claims, wherein the automatic store (3) comprises a plurality of trays (30) predisposed to contain ordered rows of items (C); the trays (30), which are stockable internally of the automatic store (3) and which are commandably transferable in inlet between a loading position, in which they receive the items (C), and at least an unloading position, in outlet, from which the items (C) are supplied to the stacking device (4), the trays (30) being associated to means for enabling an ordered positioning of the single items (C) in at least a row for each shelf or tray (30). 7). The plant of claim 6, wherein the means comprise parallel slits on a bottom of the trays (C) internally of which, at the loading and unloading positions of the automatic store (3), transporter belts are insertable, which transporter belts move from an inactive position, in which the belts do not interfere with the bottom of the trays (30), into a commandable raised active position in which the belts project superiorly from the slits and contact the items (C) making up the row, such as to raise them from resting on the bottom of the trays (30); the transporter belts being activatable on command. 8). The plant of one of the preceding claims, wherein a processor is predisposed to receive the identifying data of each item (C) and the identifying data of a position of each item (C) on the tray (30) on which the item (C) is positioned and a position of each item (C) internally of the automatic store (3).

9). A method for pallet-stacking, comprising following stages: collecting single items (C) from a pallet; identifying the items (C); arranging the items (C) in determined positions internally of an automatic store (3); removing a determined number of predetermined items (C) from the automatic store (3); making up the predetermined items (C) on a pallet.

10). The method of claim 9, wherein the stage of identifying the items (C) comprises a further stage of assigning to each item (C) a datum relating to a determined position thereof internally of the automatic store (3).