DEVICE AND METHOD FOR FORMING A CONTAINER BY FOLDING

Abstract

The present invention relates to the forming of a container by folding a cardboard sheet with at least vertical flaps, using a forming device and a forming method. Such a device comprises an upstream conveyor driving said cardboard sheet in a direction of travel, a downstream conveyor, means for folding the vertical flaps, said folding means being situated symmetrically about said upstream conveyor, and is characterized in that, on each side, said folding means comprise a pair of downstream and upstream pushers forming a gripper, said pushers being actuated jointly from an open position toward a closed position of folding said corresponding vertical flaps, a support for each gripper, said support being mobile in said direction of travel.

Claims

1. A device (2) for forming a container (1) by folding a cardboard sheet (100), said sheet (100) being provided with at least vertical flaps (106), comprising at least: an upstream conveyor (3) driving said cardboard sheet (100) in a direction of travel; a downstream conveyor (4); means (5) for folding the vertical flaps (106) of said cardboard sheet (100), said folding means (5) being situated symmetrically on either side of at least said upstream conveyor (3); wherein, on each side, said folding means (5) comprise: a pair of downstream and upstream pushers (50) forming a gripper, said pushers (50) being actuated jointly from an open position toward a closed position of folding said corresponding vertical flaps (106), and vice versa; a support (6) for each gripper, said support (6) being mobile in said direction of travel.

2. The forming device (2) as claimed in claim 1, further comprising at least one controller controlling, in synchronized manner, the joint actuation of the pushers (50) of each gripper on each side with the movement of said support (6), with respect to the driving of said upstream conveyor (3).

3. The forming device (2) as claimed in claim 2, wherein, when the pushers (50) are in the closed position, said folding means (5) form a means of transferring said sheet (100) from said upstream conveyor (3) toward said downstream conveyor (4) by gripping it.

4. The forming device (2) as claimed in claim 1, wherein each pusher (50) is mounted with the ability to rotate with respect to said support (6).

5. The forming device (2) as claimed in claim 1, wherein the pushers (50) situated facing each other are offset vertically.

6. The forming device (2) as claimed in claim 1, wherein the pushers (50) of each gripper have adjustable separation.

7. The forming device (2) as claimed in claim 1, wherein each of said pushers (50) comprises a removable gripping head.

8. The forming device (2) as claimed in claim 1, wherein said head comprises at least a plate provided with an orthogonal concave contact surface.

9. The forming device (2) as claimed in claim 1, wherein each support is motorized for translational movement along at least a guide from an upstream position to a downstream position, and vice versa.

10. A method for forming a container (1) by folding a cardboard sheet (100), said sheet (100) being provided with at least vertical flaps (106), in which forming method at least: a cardboard sheet (100) is driven in a direction of travel on the upper surface of an upstream conveyor (3) toward at least a downstream conveyor (4); said vertical flaps (106) on each side of said cardboard sheet (100) are folded; wherein: the vertical flaps (106) situated downstream and upstream in relation to said direction of travel are folded simultaneously by gripping each side simultaneously by closing a gripper.

11. The forming method as claim 10, wherein: each gripper is moved jointly in said direction of travel in a manner synchronized with the driving of said cardboard sheet (100) by said upstream conveyor (3).

12. The forming method as claimed in claim 11, wherein: in the closed position, said cardboard sheet (100) is transferred from said upstream conveyor (3) toward said at least one downstream conveyor (4).

13. The forming device (2) as claimed in claim 2, wherein each pusher (50) is mounted with the ability to rotate with respect to said support (6).

14. The forming device (2) as claimed in claim 2, wherein the pushers (50) situated facing each other are offset vertically.

15. The forming device (2) as claimed in claim 2, wherein the pushers (50) of each gripper have adjustable separation.

16. The forming device (2) as claimed in claim 2, wherein each of said pushers (50) comprises a removable gripping head.

17. The forming device (2) as claimed in claim 2, wherein each support is motorized for translational movement along at least a guide from an upstream position to a downstream position, and vice versa.

Description

[0049] Other features and advantages of the invention will emerge from the following detailed description of nonlimiting embodiments of the invention, with reference to the appended figures, in which:

[0050] FIG. 1 schematically depicts a view in elevation of one example of a cardboard sheet;

[0051] FIG. 2 schematically depicts a perspective view of said cardboard sheet of FIG. 1 after a first step of folding the lateral walls;

[0052] FIG. 3 schematically depicts a perspective view of said cardboard sheet of FIG. 1 after a second step of folding the lid over onto the tab;

[0053] FIG. 4 schematically depicts a perspective view of said cardboard sheet of FIG. 1 after the folding of the vertical flaps;

[0054] FIG. 5 schematically depicts a perspective view of said cardboard sheet of FIG. 1 after the folding of the horizontal flaps, said case thus being formed;

[0055] FIG. 6 schematically depicts a perspective view of another cardboard sheet after it has been formed into a tray;

[0056] FIG. 7 schematically depicts a perspective view of one embodiment of the device for forming by folding, simplified to just one side of the upstream and downstream conveyors, notably showing the grippers in the open position;

[0057] FIG. 8 schematically depicts a view similar to FIG. 7, notably showing the grippers in the position of gripping and accompanying a cardboard sheet, after the folding of the vertical flaps;

[0058] FIG. 9 schematically depicts a side view of said forming device, notably showing the return travel of the mobile support after the output conveyor has taken hold of a cardboard sheet now formed into a case;

[0059] FIG. 10 schematically depicts a simplified elevation of the forming device, corresponding to a first step, notably showing the grippers situated on either side in the open position before taking hold of a sheet, with synchronized movement;

[0060] FIG. 11 schematically depicts a view similar to FIG. 10 and corresponding to a next step, notably showing the grippers in the position of gripping said cardboard sheet, after the folding of the vertical flaps;

[0061] FIG. 12 schematically depicts a view similar to FIG. 11 and corresponding to a next step, notably showing the grippers maintaining the gripped position and accompanying said cardboard sheet, taken on by the downstream conveyors;

[0062] FIG. 13 schematically depicts a view similar to FIG. 12 and corresponding to a next step, notably showing the grippers passing into the open position, releasing said sheet, formed into a case, taken on by said downstream conveyors;

[0063] FIG. 14 schematically depicts a view similar to FIG. 13 and corresponding to a next step, notably showing the return of the support from downstream to upstream with the grippers open, ready to process a next sheet.

[0064] It will be noted that, for better legibility, FIGS. 9 to 14 do not depict the horizontal flaps of the sheet.

[0065] In the context of the present invention, unless explained otherwise, it will be noted that the term “sheet” encompasses the cardboard sheet in the form of a flat box blank and also throughout all of the folding steps when the case or the tray is partially formed, up to the point at which a fully formed container 1 is obtained. Likewise, unless stipulated otherwise, the term “container” corresponds to a case or a tray that has been fully formed, namely after its horizontal flaps have been folded.

[0066] The present invention relates to the forming of a container 1 by folding of a cardboard sheet 100.

[0067] A container 1 may take the form of a case, as visible in FIG. 5, or of a cardboard tray, as visible in FIG. 6. A container 1 is intended for the packaging of products. In order to do that, a container 1 has a rectangular parallelepipedal shape, with an interior volume capable of accepting a group of products, in a staggered configuration but preferably arranged in a matrix of rows and columns, or even several groups of products superposed.

[0068] It will be noted that a product is an individual object of vessel type, such as a bottle or a vial, or else a can or even a cardboard carton. A plurality of products may also be grouped together, positioned in a sleeve pack or “cluster” and/or wrapped in a film. A product may be made of any material, notably of plastic, of metal or even of glass. A product may be rigid or semirigid. Such a vessel is intended to contain, and this list is not exhaustive, a fluid, liquid, powders or granules, notably of the agri-foodstuff or cosmetic type. A product may exhibit any type of shape, symmetrical or otherwise, regular or irregular.

[0069] To improve legibility of the drawings, the products have not been depicted in the figures. As mentioned previously, the automated making-up of containers 1 is performed by folding precut and preformed cardboard sheets 100 also known as “box blanks”.

[0070] The invention is quite especially aimed at the forming of a container 1, notably continuously, by the folding of a cardboard sheet 100. Such continuous forming is achieved by having a cardboard sheet 100 travel through an installation dedicated to the packaging of products.

[0071] It will be noted that, within the meaning of the invention, unless stipulated otherwise, travel is in a direction of travel notably visible in FIGS. 9 to 14; this direction of travel extending longitudinally through the installation, notably in a direction from upstream to downstream. The following description of the potential positions is to be understood in relation to this direction of travel, particularly so far as the terms “on either side”, “on the right” or “on the left” are concerned.

[0072] Such an installation comprises a plurality of successive workstations involved in folding the various parts of each sheet 100, while in a synchronized manner accompanying its movement, until a corresponding container 1 is obtained.

[0073] One or more workstations of the installation may be or form part of a device 2 for the forming of a container 1 by the folding of a cardboard sheet 100 according to the invention. As a preference, such a forming device 2 is dedicated to the folding of the vertical flaps 106 of said sheet 100. In short, said sheet 100 comprises at least vertical flaps 106, preferably a pair of vertical flaps situated at each end, front and rear/upstream and downstream, each vertical flap 106 of each pair being situated on each side/on the right and on the left.

[0074] Therefore, the forming device 2 or else a workstation situated upstream, performs the folding of other parts of the sheet 100, such as the simultaneous folding of the left 102 and right 103 lateral walls, then the folding of the tab 105 that takes place at the same time as the lid 104 is folded over until the volume of the future container 1 is obtained, or else the folding over of the lid 104 before the external sealing flap is folded against the corresponding left 102 or right 103 lateral wall. What is more, after the folding of the vertical flaps 106, the forming device 2, or else a workstation situated downstream, performs the folding of the horizontal flaps 107.

[0075] Moreover, at the entry to the installation, a workstation provides a supply of products, preferably grouped, and laid-flat cardboard sheets 100. Such a supply workstation notably sets the products down on the upper face of the bottom 101 of each sheet 100. That being the case, according to the invention, the forming device 2 comprises at least one upstream conveyor 3. This conveyor extends substantially horizontally, receiving each sheet 100 on its upper face. It may be of any type, preferably of the endless loop type, as visible in FIGS. 7 to 9. Furthermore, said endless loop may take the form of a moving band conveyor, a moving belt conveyor or a chain conveyor. Said upstream conveyor 3 therefore drives said sheet 100 in said direction of travel, together with the products thus transported on the sheet 100. This upstream conveyor 3 may extend over all or part of the installation, notably from the supply workstation.

[0076] The forming device 2 also comprises at least one downstream conveyor 4. As a preference, said device 2 may comprise, toward the bottom, at least a first downstream conveyor 40 and a second downstream conveyor 41. These conveyors extend substantially horizontally, approximately in alignment in the one same plane as the upstream conveyor 3. They may be of any type, preferably of the endless loop type, with a moving band, (a) moving belt(s) or (a) chain(s). Furthermore, the downstream conveyors 40, 41 are notably dedicated to the folding of horizontal flaps 107 and to the supported transportation of the container 1 that has been formed, once said lower horizontal flaps 107 have been folded. To do this, the downstream conveyors 40, 41 comprise cleats 42 spaced at regular intervals and specially configured. As a result, a sheet 100 transferred toward the downstream conveyors 40, 41 is trapped between the respective cleats 42 which, on the one hand, fold the corresponding horizontal flaps 107 and, on the other hand, trap the container 1 thus formed via its front and via its rear in order to hold it in place as it travels in the downstream direction. In particular, a cleat 42 of the first downstream conveyor 40 folds and holds in place the horizontal flap 107 situated at the rear, while a cleat 42 of the second downstream conveyor 41 folds and holds in place the horizontal flap 107 situated at the front, or vice versa, the order being of very little importance, or simultaneously. This holding-in-place is notably visible in FIGS. 9, 13 and 14.

[0077] Likewise, the forming device 2 may comprise, at the top, similar upper downstream conveyors, which have not been depicted. These upper downstream conveyors are positioned above the plane of the other conveyors, at a height that is defined according to the dimensions of the container 1 that is to be formed. The upper downstream conveyors, which are also equipped with cleats, then fold the horizontal flaps 107 situated higher up or at the top.

[0078] More specifically, the forming device 2 comprises means 5 for folding the vertical flaps 106 of said cardboard sheet 100. Such folding means 5 are mounted on a fixed structure, attached to the installation, to the floor and/or to at least the upstream conveyor 3.

[0079] Said folding means 5 are situated symmetrically on each side of at least said upstream conveyor 3. As a preference, said folding means 5 extend on each side of the upstream conveyor 3 and of the at least one downstream conveyor 4, notably at the adjacent ends of these conveyors. The folding means 5 are therefore positioned at the end of the upstream conveyor 3 and at the start of the downstream conveyor 4.

[0080] As a result, advantageously, the invention makes provision for holding the case 100 in place with improved folding of the vertical flaps 106, providing positive referencing during the transfer between the upstream conveyor 3 and the downstream conveyor 4. In so doing, the invention makes provision for all the vertical flaps 107 to be folded at the same moment, but also for the case 100 to be held in place once this folding has been performed, until such point as it is taken on by said at least one downstream conveyor 4.

[0081] To do this, on each side, said folding means 5 comprise at least a pair of downstream and upstream pushers 50 forming a gripper. In addition, said pushers 50 are actuated jointly from an open position toward a closed position of folding said corresponding vertical flaps 106. Conversely, the actuation of the pushers 50 moves them from the closed position toward the open position. It will be noted that, in the closed position, the pushers 50 are closed or clamped together. In the open position, the pushers 50 are retracted, which is to say that they do not interfere with the path of movement of the sheet 100.

[0082] More specifically, one pair of pushers 50 is situated on the left while another pair is situated on the right. Each pair forms a gripper able to fold the vertical flaps 106 situated at the front and at the rear, on the corresponding side. As a result, all the pushers 50 are actuated jointly, so as to perform simultaneous folding of all the vertical flaps 106. In short, the right and left grippers are closed together, ensuring uniformly distributed forces on the sheet 100, reducing the risks of deformation, of offsetting and of unwanted shifting of the products.

[0083] What is more, said folding means 5 comprise at least a support 6 for each gripper, namely for a pair of pushers 50 that is situated on the right and for a pair situated on the left. Advantageously, said support 6 is mobile in said direction of travel. In short, each support 6 is driven on an outbound path from upstream toward downstream and conversely along a return path. Furthermore, the folding is performed along the outbound path, whereas the grippers are open along the return path, as visible in FIG. 14.

[0084] In this way, the movement of each support 6 allows the grippers to accompany the travel of the sheet 100, notably ensuring the continuous aspect of the forming. This movement of each support 6 means that, once the vertical flaps 106 have been folded, the sheet 100 now held in place and trapped between the grippers can be moved, particularly during the transfer between the upstream conveyor 3 and the at least one upstream conveyor 4, until the latter takes it on, whereupon the container 1 can then be released by opening the grippers. This transfer up to the point of this takeover is notably visible in FIGS. 11 to 13.

[0085] Each support 6 is driven linearly by suitable motorized means, in the form of a drive belt or chain, or even using a linear motor.

[0086] It will be recalled that a linear motor is an electric motor in which each rotor and each stator are unwrapped, in particular flat; the linear motor generates a force for moving, in particular in translation, at least one rotor relative to the stator. In this instance, as a preference, each support 6 forms a rotor that is moved along one or more stators.

[0087] In this respect, the folding means 5 may comprise a guide 7 for each support 6. Each guide 7 extends longitudinally over a determined distance, approximately corresponding, before the end of the upstream conveyor 3 and after the takeover by the at least one downstream conveyor 4.

[0088] In the case of a linear motor, each guide 7 then forms a stator.

[0089] According to the above-mentioned embodiments, each support 6 is then motorized for translational movement along at least a guide 7 from an upstream position to a downstream position, and vice versa.

[0090] According to another possible embodiment, each support 6 is mounted at the end of a robot arm, of a multi-axis robot or articulated robot type.

[0091] As a preference, in order to coordinate the operation of the device 2 with the movement of the sheet 100, said forming device 2 may comprise at least one controller controlling, in synchronized manner, the joint actuation of the pushers 50 of each gripper on each side with the movement of said support 6, with respect to the driving of said upstream conveyor 4. Such a controller may in the conventional way comprise computer means and/or automatic means necessary for its operation and for its configuration by an operator. Thus, the invention provides a specific controller which manages the movements of the supports 6 and the simultaneous opening/closing of the pushers 50 with respect to the movement of the sheet 100 on the upstream conveyor 4.

[0092] Furthermore, the movements of the supports 6 are controlled in perfect synchrony, on the right as on the left. In short, the longitudinal positions of the supports 6 are the same at each instant, as are their speeds.

[0093] In addition, the controller is therefore able to synchronize the supports 6 both in position and in speed so that the pushers 50 perfectly face the vertical flaps 106 and so that said supports 6 accompany the movement of the sheet 100 that is to be folded and grasped for transferring it.

[0094] The controller may also allow the movement of the supports 6 to be accelerated, notably in order to reduce the time spent on the return path when the folding means 5 are empty with the pushers 50 in the open position, allowing them to return more swiftly in order to process the next sheet 100.

[0095] In this respect, once the sheet 100 has been grasped by the grippers, as it leaves the upstream conveyor 3, controlling the mobility of the supports 6 makes it possible to maintain the same speed, to accelerate or to decelerate, in order to establish a reference with respect to said at least one downstream conveyor 4, notably the positions of the corresponding cleats 42.

[0096] More specifically, when the pushers 50 are in the closed position, said folding means 5 form a means of transferring said sheet 100 from said upstream conveyor 3 toward said downstream conveyor 4 by gripping said sheet. In short, the forming device 2 comprises means for transferring the sheet by grasping hold of it, these transfer means consisting of the folding means 5 in the form of pushers 50 mounted on a mobile support 6.

[0097] More specifically, according to a preferred embodiment, as visible in FIGS. 7 and 8, each pusher 50 is mounted with the ability to rotate with respect to said support 6. In particular, such rotation may be brought about via at least one pivot point, as visible in FIGS. 10 to 14. Each pusher 50 therefore rotates in order to pass from the open position to the closed position. Such rotation notably makes it possible to reduce the incident forces liable to shift the sheet 100 or the products during the course of the folding of the vertical flaps 106.

[0098] According to another embodiment, the pushers 50 may be subjugated to one or more linear movements, or a combination of such linear movements, via a suitable mechanism.

[0099] According to one embodiment, the pushers 50 of each gripper have adjustable separation In short, it is possible to move them closer toward or further away from the support 6 in order to adapt their distance according to the length of sheet 100 to be processed.

[0100] According to one embodiment, each of said pushers 50 comprises a removable gripping head. In short, it is possible to change the heads of the pushers 50 according to the dimensions of the sheet 100. Thus, by keeping the same mechanism for the pushers 50, changing the head provides adaptability to suit the need.

[0101] More specifically, as a preference, said head may comprise at least a plate provided with an orthogonal concave contact surface. In short, the contact face intended for folding the vertical flaps 106 has a squared-off shape, with perpendicular walls. This shape notably allows the vertical flaps 106 to be folded at right angles while at the same time ensuring pressure against the corresponding lateral wall 102, 103, thus improving the retention of the sheet 100 during the folding and after it has been grasped for transferring it.

[0102] According to one embodiment, the pushers 50 situated facing each other are aligned in the one same plane or substantially the same planes. These planes are horizontal or substantially horizontal, parallel to the plane containing the surface of the upstream conveyor 4 and also the surface or surfaces of the downstream conveyor or conveyors 4, 40, 41.

[0103] More specifically, the pushers 50 may be dimensioned and positioned at a height that is adjustable so that the horizontal flaps 107 can be folded, without interference, while said pushers 50 are in the closed position.

[0104] It will be noted that it is also possible to open the pushers 50 at any moment, notably during the course of the folding of the horizontal flaps 107, so that the pushers 50 do not interfere during this operation.

[0105] According to another embodiment, the pushers 50 situated facing each other are offset vertically. In short, the pushers 50 on the right are higher up or lower down than the pushers 50 on the left. Thus, it is possible for the pushers 50 to cross one another as they close, transversely improving the grip of the sheet 100 over a greater width, notably beyond the width of the vertical flaps 106.

[0106] In such cases, with reference to the corresponding embodiment, the plate may exhibit a longer distal part. Furthermore, this lengthened distal part may enable any products that may have shifted from their initial position to be repositioned correctly by pushing them back toward the inside of the sheet 100.

[0107] The invention relates to a method for forming a container 1 by folding a cardboard sheet 100.

[0108] Such a forming method may be particularly suited to implementation of the forming device 2 according to the invention.

[0109] During the course of this forming method, at least a cardboard sheet 100 is driven in a direction of travel. This driving is done on the upper face of the upstream conveyor 3 toward said at least one downstream conveyor 4.

[0110] During the movement of said sheet 100, said vertical flaps 106 on each side of said cardboard sheet 100 are folded. In short, the vertical flaps 106 on the right and those on the left, on each side, are folded.

[0111] Advantageously, the vertical flaps 106 situated downstream and upstream with respect to said direction of travel are folded simultaneously. In addition, this folding is performed by simultaneously gripping each side by the closing of a gripper, namely a right and a left gripper at the same time. Furthermore, in the closed position, the grippers keep each sheet 100 grasped and accompany it as it is transferred.

[0112] With reference to the corresponding embodiment of the forming device 2, each gripper comprises pushers 50 and it is these that perform the folding by passing toward their position in which the corresponding gripper is closed.

[0113] In addition, as a preference, in the closed position, said cardboard sheet 100 is transferred from said upstream conveyor 3 toward said at least one downstream conveyor 4.

[0114] In either instance, the method manages the movements of the grippers, on the one hand, from their open position to their closed position, and vice versa, and on the other hand in terms of their longitudinal travel in the direction of travel.

[0115] In order to achieve this, each gripper is moved jointly in said direction of travel in a manner synchronized with the driving of said cardboard sheet 100 by said upstream conveyor 3.

[0116] In the case of the corresponding embodiment of the forming device 2, this management can be performed by the controller.

[0117] Thus, the way in which the container 1 is formed according to the invention, by simultaneously folding the four vertical flaps 106, at the front and at the rear and on the right and on the left, particularly via a rotation of the pushers 50, limits the disturbing forces liable to cause a loss of synchronization of the sheet 100 with respect to the machine.

[0118] The positive grasp by the grippers means that the sheet 100 is accompanied as it is transferred between the conveyors 3, 4, or even allows the sheet to be repositioned if it becomes slightly shifted. This retention of the cardboard sheet 100 by grasping it also means a high production rate can be ensured, or even that it can be accelerated.