EP0526677A1 - Method and device for feeding flat articles from at least one pile of those articles to a machine - Google Patents

Abstract

The invention relates to a method and a device for feeding a work station. It will find its application in particular in the cardboard-industry field for feeding cardboard-panel or cardboard-blank converting machines from at least one pile of such articles. According to the invention, a storage zone is formed in which the piles (5) are substantially contiguous, all the said piles (5) are moved towards a separation zone (6) in which a pile (7) is secured. Next, the said articles are taken up, continuously, one by one from the bottom of the pile (7) and the said articles, thus picked up (9), are transferred, forming a continuously moving layer (10) in the form of overlapping scales which is supported and directed towards the said work station (2). <IMAGE>

Description

The invention relates to a method and a device for supplying a work station with flat products from at least one stack of such products.

The invention will find its application in particular in many fields of industry where it is necessary to work such flat products in different work stations. One of the applications of the present invention relates to the field of cardboard where it is common to form stacks of flanks or sheets of cardboard which are then taken up and used to supply different machines such as for example cutting presses, presses to print, etc ...

In this area, the raw material, namely the sides or sheets of cardboard, is obtained from corrugating machines which, after cutting the strip longitudinally and transversely at the outlet of the machine, make it possible to form stacks of flat coated sheets.

These different stacks are stored before their reuse, and in many cases, the feeding of the processing machines is done manually by an operator who brings a stack of plates and deposits them in acceptable packets in the feeder of said machine.

In the case of automated installations, so-called "automatic feeders" are known which make it possible, from a stack of flat plates lying in cardboard, to form packets of plates in a smaller number to supply, for example, the feeder of a processing machine.

However, depending on the rate of use of the plates, it is necessary to carry out an intermediate storage of the batteries before their use in the said automatic feeders. This storage is generally carried out on roller tables on which the stacks are placed vertically and which allow an operator to manually bring the stack by gently pushing it along this raceway towards the work station.

A first particular problem arises when it is necessary to transfer or handle batteries whose height is large relative to the dimensions of its support base. Indeed, their balance is precarious and if no particular attention is paid, it will be common to see such batteries collapse.

The landslides have various causes and depend for example on the straightness of the stacking, accelerations during the movements of the stack, untimely blockages of the bottom of the stack, etc ... These landslides naturally affect the cost of returns from the finished product because the loss of time thus caused affects the labor required for the finished product.

Another problem inherent in existing installations resides in the fact that it is imperative to have raceways which connect the storage areas to the machines or the machines between them, and which, generally constituted by roller tables, occupy the ground surface by hampering free movement between machines and storage areas.

This is detrimental in certain cases because it is common to have to intervene around working machines for their maintenance or other, and the presence of roller raceways constitutes an insurmountable annoyance.

To overcome some of these drawbacks, a method has been devised for transferring a stack of flat products and a device for handling such a stack, the aim of which is to allow free movement at ground level between the various stations. work area and storage area by clearing the floor area and avoiding the use of roller tracks to the machine to be serviced.

For this, a battery transfer cart, of the "shuttle" type, is used which is capable of taking a battery vertically from a storage area, and of moving it to the work station avoiding the landslide during path.

However in these systems, it is necessary to lift or lay the stack, which generates a significant consumption of energy and time, to provide sophisticated embodiments such as telescopic tables and movable on rails, which also influences the cost of finished products.

The object of the present invention is to provide a method and a device for supplying a work station with flat products from a stack of such products which make it possible to overcome the drawbacks of existing devices, and which nevertheless allow production at high rates, while lowering the cost price of finished products.

One of the aims of the present invention is to propose a method and a device for supplying a work station with flat products which no longer require the displacement over long distances of the vertical piles which thus prevent their untimely collapse.

Another object of the present invention is to provide a method and a device for supplying a work station with flat products which have a light and retractable infrastructure in order to allow access to said work station without being hindered by the power plant.

One of the aims of the present invention is to apply the method and the feeding device to the cardboard sector in order to allow automatic feeding of the processing machines. Mation from a stock of sidewall or cardboard stacks, whatever their size, avoiding manual intervention, having reliable operation and minimizing the time lost and the energy consumed.

Another object of the present invention is to provide a method and a device for supplying a work station with flat products which admit a large number of products to be processed of non-imposed dimensions while allowing automatic centering of the stack of input products.

Furthermore, when handling the products in stacks, it is common for the bottom stack plate to be soiled, in particular by the roller conveyors of the storage store. One of the aims of the present invention is to allow the evacuation of this bottom stack plate in order to prevent it from being processed by the said work station and subsequently constitutes a defective product.

Other objects and advantages of the present invention will emerge during the description which follows, which is however only given for information, and which is not intended to limit it.

• - on forme une zone de stockage dans laquelle les piles sont sensiblement contigües,
• - on déplace l'ensemble des dites piles vers une zone de séparation dans laquelle une pile est assujettie,
• - on prélève, en continu, un à un les dits produits par le bas de la pile,
• - on transfert les dits produits ainsi prélevés en formant une nappe en écaille en mouvement continu que l'on supporte et dirige vers le dit poste de travail.

According to the present invention, the method of supplying a work station with flat products, such as for example sidewalls or cardboard plates, from a stack of such products, is characterized in that:

• - a storage area is formed in which the stacks are substantially contiguous,
• - all of said stacks are moved to a separation zone in which a stack is subjected,
• - one takes, continuously, one by one the so-called products from the bottom of the stack,
• - Transferring the so-called products thus removed by forming a continuous sheet of flake which is supported and directed towards the said work station.

• - des moyens de prélèvement des produits plats un à un par le bas de la pile,
• - des moyens pour former une nappe en écaille à partir des dits produits ainsi prélevés,
• - des moyens de transfert, escamotables au moins en partie, aptes à supporter et diriger la dite nappe ainsi formée vers le poste de travail.

The device of the invention, allowing the implementation of the method of supplying a work station with the aforementioned flat products, comprising at least one storage area on which stacks are disposed substantially contiguous, is characterized in that 'it comprises :

• means for removing the flat products one by one from the bottom of the stack,
• means for forming a sheet of tortoiseshell from the said products thus taken,
• - Transfer means, retractable at least in part, capable of supporting and directing said sheet thus formed towards the work station.

• La figure 1 montre une vue en perspective d'un dispositif d'alimentation d'un poste de travail en produits plats, tels que par exemple des flancs ou plaques de carton, à partir d'au moins une pile de tels produits.
• La figure 2 montre une vue schématique de profil du dispositif représenté à la figure 1 en position travail, c'est-à-dire pour la délivrance des produits plats au poste de travail.
• La figure 3 montre un détail de la machine illustrée aux figures 1 et 2 illustrant le prélèvement des produits un à un par le bas de la pile.
• La figure 4 montre une vue de profil de la machine représentée à la figure 2, en position non utilisation, les moyens de transfert étant escamotés pour laisser le libre accès autour du poste de travail.
• La figure 5 montre en vue de profil une partie de la machine de la présente invention équipée de différentes variantes.

The present invention will be better understood on reading the following description accompanied by the accompanying drawings which form an integral part thereof.

• FIG. 1 shows a perspective view of a device for supplying a work station with flat products, such as for example sidewalls or cardboard plates, from at least one stack of such products.
• Figure 2 shows a schematic profile view of the device shown in Figure 1 in the working position, that is to say for the delivery of flat products at the workstation.
• Figure 3 shows a detail of the machine illustrated in Figures 1 and 2 illustrating the removal of products one by one from the bottom of the stack.
• Figure 4 shows a side view of the machine shown in Figure 2, in the non-use position, the transfer means being retracted to allow free access around the workstation.
• Figure 5 shows a side view of a part of the machine of the present invention equipped with different variants.

The invention relates to a method and a device for supplying a work station with flat products from at least one stack of such products.

Although this was more particularly developed in the cardboard sector in order to handle the sides or plates of cardboard and to supply machines for processing such products, it could be applied to any other type of batteries. of flat products to handle.

In addition, the present invention will find an advantageous use when the stacks of such products have a significant height relative to the dimensions of the support base, which influences the stability of such a stack.

Currently, to power the workstations, the batteries are moved manually taking all the precautions or one proceeds mechanically, either by dividing the stack into bundles whose balance is more stable, or by transporting the stack while maintaining it to avoid that it does not collapse.

Such operations have repercussions on the cost price of the finished product, because it is necessary to use an abundant workforce in the case of manual work or to use more or less sophisticated machines consuming considerable energy, which also increases the cost price.

The solution provided by the present invention makes it possible to automate the supply of workstations and proposes an original process different from those existing, requiring minimum mechanical means, also absorbing minimum energy and reliable and safe operation, while authorizing, when desirable, free access around the workstation concerned.

Figures 1 and 2 illustrate in particular the method of the present invention as well as an embodiment of the device implementing said method.

On the one hand there is a storage area 1 and on the other hand a work station to be supplied 2, spaced from one another and joined by the supply device 3 of the present invention.

In FIG. 1, the storage area 1 is shown empty to illustrate its structure, advantageously constituted by a traditional roller conveyor table 4, motorized or not, on which the stacks 5 of products will rest vertically.

As shown particularly in FIG. 2, in the storage area 1, the different stacks 5 are stored in a contiguous manner. This arrangement advantageously makes it possible to reinforce the stability of the different stacks thanks to the contact of the lateral sides of said stacks 5. Thus, the collapse of said stacks is avoided because they support each other.

For example, good results have been obtained in supplying workstations from stacks of about two meters in height made up of cardboard sides of width between 200 and 1,500 mm and length between 500 and 3,000 mm. However, it could be envisaged to use batteries of different dimensions which would have a more natural stability and which could then be isolated from each other.

This storage area 1 being formed, according to the method of the invention, all of said stacks 5 are moved to a separation area 6 in which a stack 7 is secured.

To take account of the precarious stability of the stacks in certain cases, the contiguous stacks 5 are arranged in a row on the conveyor 4 and the entire row is moved, step by step, towards the separation zone 6 each time that one of the subject batteries 7 is transferred.

As specified above, the stacks support each other during transfer and, in addition, the front face 8 of the subject stack 7 is maintained in said separation zone 6 over its height.

That said, at the level of said separation zone 6, one takes one by one, the so-called products from the bottom of the stack 7, continuously, then the said products thus taken are transferred 9 by forming a sheet 10 in tortoiseshell in continuous movement which is supported and directed towards said workstation 2.

In addition, to facilitate the transfer of said products 9, and in particular to facilitate the mounting of the plates and also facilitate the control and removal of bad plates by an operator during their transfer, their path of movement is at least partly in arc of circle, as shown particularly in Figure 2.

According to one embodiment of the supply device 3 of the present invention, it comprises at least one storage area 1 on which the said batteries 5 are arranged substantially contiguous, as well as means for taking off products 11, 12 one from the bottom of the stack, means 13 for forming a shell ply 10 from the products 9 thus removed, and transfer means 14, retractable at least in part, capable of supporting and directing said ply 10 thus trained to workstation 2.

• - d'un tablier vertical 12, apte à maitenir la face avant 8 de la pile 7 assujettie dans la zone de séparation 6, sur au moins une partie de sa hauteur,
• - d'un plan de pose 11 de la dite pile 7, dont la surface est apte à être mise en mouvement de façon à créer un mouvement de translation 17 du produit inférieur 15, de la dite pile assujettie, en contact avec la dite surface.

As regards the said means of taking products one by one from the bottom of the stack, they are advantageously constituted by the combination:

• a vertical deck 12, capable of holding the front face 8 of the stack 7 secured in the separation zone 6, over at least part of its height,
• - A laying plane 11 of said pile 7, the surface of which is capable of being set in motion so as to create a translational movement 17 of the lower product 15, of said subject pile, in contact with said surface .

The separation movement is more particularly illustrated in FIG. 3 which shows the lower part of the stack 7 secured in contact with the laying plane 11 and maintained by the deck 12.

Said deck 12 and said laying plane 11 define between them a space 16 such that at least said product 15, moving towards the deck 12, can be taken from the stack from below.

In an advantageous embodiment, said laying plane 11 is constituted by an endless belt conveyor, with continuous motorized movement, the face of which receiving the stack 7 is animated by a movement shown diagrammatically at 17, that is to say - saying tending to move the entire stack towards the deck 12.

Thanks to the coefficient of adhesion between the products of the lower part of the stack 7 with the carrying belt 11, to the coefficient of friction of the products between them, to inertia, as well as to said space 16 left at the lower part of the vertical apron 12, at this level we will dispense the products one by one from the bottom of the stack.

Firstly, the product 15 immediately in contact with the belt 11 will be entrained as shown in FIG. 3, then when the product 18 immediately above said product 15 will have a sufficiently large contact surface with the belt 11, this ai will also cause it by causing an overlap between the products 15 and 18. In this case, the space 16 must have a height at least sufficient to let two products 15, 18 overlap. It should be noted that this space will advantageously be adjustable according to the products to be treated.

At the exit of the sampling station 6, we re finds the said means 13 to form a sheet 10 in tortoiseshell from the products 9 thus sampled.

More specifically, these ply forming means are constituted by a conveyor 13, in particular with endless belts, motorized with continuous movement, arranged just downstream of said laying plane 11 of the sampling means, in order to continue the translational movement. 17 of said product 9 taken.

Naturally, the two conveyors 11 and 13 could be different, but in the embodiment shown, the said laying plane 11 of the stack 7 and the said means 13 for forming the sheet of flake are advantageously constituted by the same endless conveyor with continuous movement.

However, the vertical apron 12 will be arranged transversely to said common conveyor 11-13 and will be able to be adjusted according to the width of the format of the products in order to provide on the belts of the conveyor 11 the location corresponding to the dimension of the format as the particularly show the figures.

Then, downstream of the said means 13 for forming the woven sheet and upstream of the said work station 2, the said transfer means 14 are arranged, at least partly retractable.

More specifically, these transfer means consist of an assembly of conveyors 19-20, in particular of the endless belt type with motorized continuous movement, mounted in articulation 21 at the end of the conveyor 13 for forming the sheet, and subject to a control member 22-24, to authorize the lifting of said assembly 19-20 and allow free access around the workstation 2, as shown particularly in FIG. 4.

It should be noted that, in the example shown, said transfer means are constituted by an assembly of two conveyors 19-20. However, this was chosen to facilitate mechanical production, because it could be envisaged to use only one conveyor, liftable according to the same principle.

In this regard, the said assembly of retractable conveyors 19-20 has, in the web transfer position, a movement path substantially in an arc to facilitate handling, as has been pointed out previously.

As regards the production of said lifting control member, the principle of the deformable articulated triangle has been retained, two sides of which are fixed and the third expandable.

More precisely, this triangle is formed on the one hand by a part 25 of the conveyor 20, forming the first side of the triangle of fixed dimension, on the other hand by a guide bar 23, forming the second side of the triangle of fixed dimension and finally by a jack 22 forming the third side of the triangle whose dimension is variable.

In addition, the rod of the actuator 22 is integral and articulated at 26 on the conveyor 20 to be raised. Similarly, the guide bar 23 is integral and articulated at another point 27 of the conveyor to be raised. The spacing between the joints 26 and 27 then defines the first side 25 of the aforementioned triangle.

However, the other end of the actuator 22 and the other end of the guide bar 23 are integral and articulated together at 28, and this connection is subject to a rack assembly 24 integral with the ground

The operation of such a system is shown in Figures 2 and 4.

When the rod of the jack 22 is retracted, the small dimension of the triangle is then obtained and the transfer path 19-20 is placed substantially horizontally to transport the sheet 10 from the conveyor 13 to the supply station 2, as shown in the figure 2.

On the other hand, when the rod of the jack 22 is fully deployed, the largest dimension of the triangle is then obtained which, consequently, allows the conveyors 19-20 to rotate relative to their articulation 21 and relative to the ground, this which brings the conveyor 19 substantially vertically, and the conveyor 20 in a very raised position, completely freeing access all around the work station 2 as shown in FIG. 4.

It should be noted that, in this maximum position, that is to say transfer means 14 contracted and raised, the space occupied by the device of the invention represents substantially only the size of the conveyor 11-13, this which is one of the advantages of the present invention.

Maintaining in the raised position of the transfer means is authorized on the one hand by blocking the rod of the jack in the extended position, and on the other hand, on the rack assembly 24 cooperating with a toothed wheel 29, provided at the joint 28 common between the guide bar 23 and the jack 22.

It should however be noted that other lifting means could have been imagined.

Finally, to supply the work station 2 properly so-called, there will be available, for example, downstream of the said retractable assembly 19-20, constituting the lifting part of the said transfer means 14, a supply conveyor 30, for example substantially constituted by a conveyor belt or endless belt with continuous motorized movement, capable of receiving said sheet 10 in tortoiseshell.

In one embodiment of the invention, this conveyor 30 is mounted on the rear stop 31 of the feeder 32. Thus, by equipping the feeder with a front jogger, it is no longer necessary to adjust according to the format, because the tablecloth 10 of products in flake is poured onto the conveyor 30, the said rear stop 31 having to be adjusted to a position suitable for the jogger, at the same time adjusting the correct position of the conveyor 30.

However, in the case where the front jogger is incorporated at the end of the conveyor 20 and fixed on the latter, it is the entire feed assembly which will then have to be moved, depending on the format, to each new format.

The device of the present invention, thus described, therefore makes it possible to debit the stacks 5 one after the other, making them travel the minimum distance, and above all without the need to separate them when they are transferred.

Indeed, the transfer of the stack takes place only over a distance corresponding to its width at the level of the separation zone. There follows a minimum time for passing from one pile to another without mechanical complication, by advancing one step all the piles at the same time on the roller conveyor 4 of the storage area.

Other advantages are also remarkable because the flow rate of the stack is carried out without having to lift or lay it down. In addition, when changing format, it is only necessary to adjust the usual feeder 31-32 and the positioning of the deck 12 of the separation zone 6.

Finally, remember that in addition to the advantages, we find, when the conveyors 19-20 are raised, the possibility of having free access all around the workstation without being hindered by the infrastructure of the feeding device of this machine .

However, other embodiments of the present invention, within the reach of ordinary skill in the art, could have been envisaged, without departing from the scope thereof.

On this subject, in the preceding description, the movement of the various conveyors 11-13-19-20 is envisaged continuously; however, it should be noted that their servo-control can be provided for the operation of the feeder of the machine 2 thus supplied, either by varying the transfer speeds and / or by stopping their operation periodically as a function of the condition of the feeder and of its filling.

FIG. 5 shows different variants of the means described above which can be applied to the machine illustrated for example in FIG. 1.

In particular, instead of providing all of the means 11, 12, 13 at a fixed station relative to the ground, this assembly 11-13 may be provided at the level of a carriage 40 which can be moved relative to the ground 41 by means of rollers 42 and rolling rails 43 perpendicular to the direction of movement of the ply.

Thus, by moving the carriage 40 laterally, there will advantageously be a possibility of automatic centering of the new stack at the input of the machine at the level of the means 11, 12, which will advantageously make it possible to compensate for a misalignment of the products of the stack relative to the system.

Furthermore, at the level of the means 11 constituting the laying plane of the subject stack, there may also be provided at the input a driven roller 44 and adjustable in height allowing the rear of the stack to be raised.

This roller makes it easier to pick up the sheets one by one from the bottom and also a correct positioning of the stack on the deck 12.

This can be practically achieved by an endless conveyor, one of the rollers of which is mounted movable in the vertical direction and actuated by a jack 45 for example.

However, as we recalled above, it is common for the flank or the cardboard plate constituting the bottom of the stack to be soiled by roller conveyors during transport upstream of this device, for example by conveyors roller 4 of storage area 1.

In order to eliminate the bottom stack plate, a relative movement of the conveyor 19 relative to the conveyor 13 can be advantageously provided at the level of which the scale sheet is formed.

This relative movement, indicated by the arrow 46 in FIG. 5, makes it possible to cause a break at the level of the path of movement and the soiled plate will escape, as arrow 47 suggests. When this plate is evacuated, the mat 19 resumes its primitive place.

Such an arrangement can be implemented on the device shown in Figures 1 to 4. However, Figure 5 shows a variant of the device 3

In this case, the conveyors 19, 20 are mounted on a frame 48, in particular movable by means of rollers 49 resting on the ground.

The frame 48 comprises a hinge 50 as well as two jack systems 51, 52 allowing the lifting of the conveyors 19 and / or 20.

Claims (16)

1. Method for supplying a station (2) with flat products (9), such as, for example, flanks or cardboard plates, from at least one stack (5,7) of such products, characterized in what: - a storage area (1) is formed in which the stacks (5) are substantially contiguous, - all of said stacks (5) are moved to a separation zone (6) in which a stack (7) is subject, - said products (9) are continuously removed one by one from the bottom of the stack (7), - Transferring said products thus removed (9) by forming a sheet (10) in continuous movement tortoiseshell which is supported and directed towards said work station (2). 2. Method according to claim 1, characterized in that, in the storage area (1), the contiguous stacks (5) are arranged in a row on a conveyor (4) and the entire row is moved not step by step. 3. Method according to claim 1, characterized in that one maintains the front face (8) of said subject stack (7) in said separation zone (6) over its height. 4. Method according to claim 1, characterized in that, during the transfer of said products (9), their path of movement (20) is at least partly in an arc. 5. Device for supplying a work station with flat products, such as for example sides or cardboard plates, from at least one stack of such products, authorizing the implementation of the method of claim 1 , comprising at least one storage area (1) on which said stacks (5, 7) are disposed substantially contiguous, characterized in that it comprises: - means for removing (11-12) products one by one from the bottom of a stack (7), - means (13) for forming a sheet (10) in scale from the products (9) thus removed, - Transfer means (14), retractable at least in part, capable of supporting and directing said ply (10) thus formed towards the work station (2). 6. Device according to claim 5, characterized in that the said sampling means consist of the combination of: - a vertical deck (12), capable of holding the front face (8) of a stack (7), - A laying plane (11) of the stack (7) whose surface is capable of being set in motion so as to create a translational movement (17) of the lower product (15) of the stack (7), in contact with it, towards the apron (12), - Said deck (12) and said laying plan (11) defining between them a space (16) such that at least said product (15) in movement can be taken from the bottom of the stack. 7. Device according to Claim 5, characterized in that the said means for forming a sheet of flakes consist of a conveyor (13), arranged downstream of the said laying plane (11) of the sampling means, capable of continuing the translational movement (17) of said product sampled. 8. Device according to claim 7, characterized in that the said laying plane (11) and the said means (13) for forming the sheet are constituted by the same motorized conveyor with endless belts with continuous movement. 9. Device according to claim 5, characterized in that the said retractable transfer means (14) are constituted by an assembly of conveyors (19-20), endless belt with continuous movement, arranged upstream of said station work (2) and downstream of said means (13) for forming the ply, mounted in articulation (21) at this level, and subject to a control member (22-24) to authorize the lifting of said assembly (19 -20) and allow free access around the workstation (2). 10. Device according to claim 9, characterized in that said assembly of conveyors (19-20) has, in the web transfer position, a movement path (20), substantially in an arc to facilitate handling of the plates , quality control and removal of bad plates. 11. Device according to claim 9, characterized in that said lifting control member is constituted by at least one actuator (22) whose rod (26) is integral and articulated with the conveyor (20) to be raised, and whose the other end (28) is subject to a rack assembly (24) secured to the ground, as well as to a guide bar (23) secured and articulated at said conveyor (20) to be raised; the conveyor (20, 25), the jack (22) and the bar (23) defining a triangle of which one of the sides (22) is expandable, and allowing the lifting of said conveyor (20) by rotation around a articulation (21). 12. Device according to claim 9, characterized in that the said transfer means (14) further comprise a conveyor (30) for actual supply of the work station (2), substantially constituted by a belt conveyor without end in continuous movement, arranged downstream of said retractable assembly (19, 20), capable of receiving said ply (10) in scale. 13. Device according to claim 8, characterized in that said conveyor (11-13) has at its inlet a roller (44) adjustable in height to raise the rear of the stack (7). 14. Device according to claim 5, characterized in that the said means (11-13) are provided at the level of a carriage (40) movable laterally relative to the direction of movement of the sheet, to allow automatic centering of the battery (7). 15. Device according to claim 9, characterized in that the conveyor (19) has a relative movement (46) relative to the conveyor (13) to cause a break at the path of movement of the web to let escape a plate (9). 16. Device according to claim 15, characterized in that the conveyors (19, 20) are mounted on a frame (48) having a joint (50) as well as two jack systems (51, 52) allowing the lifting of said conveyors (19 and / or 20).

Images