WO1999007545A1 - Method and machine for assembling a box with polygonal cross-section from a flat corrugated board blank - Google Patents

Abstract

The invention concerns a method and machine for assembling a box with polygonal cross-section from a flat corrugated board blank (1) comprising an assembly of panels (12, 13, 14, 15) linked with one another by mutually parallel first folding lines (16, 17, 18) and flaps linked to said panels by second folding lines (27 to 30) and a tab (31) derived from one of the panels (12) for butt-jointing the box. The invention is characterised in that each blank is removed from a magazine, with its outer face up, then transferred horizontally, following a rectilinear path at a constant and controlled speed, towards a mandrel (3) whereon it is precisely brought before shaping alongside one of the panels coinciding exactly with the mandrel (3) top horizontal surface, and said transfer at constant and controlled speed is used for precisely depositing bond lines (58) on the tab (31) and its two small flaps (23, 25) ensuring shaping around the mandrel and/or the ink for labelling (59).

Description

 METHOD AND MACHINE FOR MOUNTING A BOX WITH POLYGONAL SECTION FROM A CORRUGATED CARDBOARD CUT

The present invention relates to a method for mounting a box with a polygonal section from a flat cut in corrugated cardboard or the like, using a forming mandrel arranged in a cantilever at the exit of a zone of transfer regulating the unstacking of a food store; the invention also relates to a machine directly implementing the method, in particular for mounting boxes with a square or rectangular section, possibly with cut sides, that is to say with cut angles. It is well known to produce polygonal boxes from flat cutouts in corrugated cardboard; these flat cutouts generally comprise a set of panels, for example four for boxes of square or rectangular section, connected to each other by first fold lines, flaps arranged on either side of said panels and connected to those -this by second fold lines perpendicular to the first, and a junction tab from the free edge of one of the end panels to which it is connected by a fold line parallel to the first to form by gluing, stapling or the like , the junction of the body at the time of assembly.

Today there are two main categories of boxes formed from corrugated cardboard blanks: - so-called "American" boxes produced from such a blank by a cardboard maker which delivers to the end user a flattened blank by folding around two diagonally opposite lines; the flattened blank is then shaped by expansion parallel to one of its diagonals then the user folds and glues a first series of flaps to form the bottom and after filling, the upper flaps are folded to close the box once fulfilled. It will be understood that such a technique is particularly long and costly since it requires the use of a machine at the cardboard manufacturer and a forming machine at the user; on the other hand, the mounting precision is uncertain, in the since it is difficult to rigorously guide the cutout by its edges when fastening the junction tab, for example. Other drawbacks also result from the median excess thickness of the flattened blanks, contributing to unbalance the stacks of blanks, during storage or during transport. It is understood, finally, that the flattening of the blank causes shearing of the folds, in particular between panels, which subsequently weakens the assembled box. As many disadvantages which led to a second technique of forming corrugated boxes, no longer from a flattened blank, but directly from a flat cut of a sheet material, such as cardboard wavy or the like. For cardboard makers, this involves making flat cutouts with all the advantages of regular flat storage, insofar as there is no longer any excess thickness as in the previous draft, and delivering them. to the end user who will assemble the boxes using a technique known as "wrap around".

In this sense, French patent FR 2,629,012 is already known for a process for producing boxes of polygonal cross section from a flat cut, as described in the preamble, which is remarkable in that the panels are wrapped around a mandrel whose outer section is identical to the inner section of the body to be obtained, by arranging for the fold lines of the body to correspond exactly with the edges of said mandrel. Then fix the junction tab on the free edge of the end panel and after having folded the small and large flaps located on the same side of the panels against a corresponding face of the mandrel, around fold lines coming in agreement with the edges of said mandrel. , said flaps are fixed and the box is ejected in the position of being filled.

According to this document, the method is characterized in that before winding the panels around the mandrel, an intermediate panel is placed, at least approximately facing the corresponding face of the mandrel, but at some distance from it, then the panels adjacent to said intermediate panel are folded and said intermediate panel is brought towards the mandrel, then all the panels are wound around the same mandrel , so that each of them is applied against one face, the fold lines connecting each panel each coming to bear against a corresponding stop of said mandrel. The machine implementing such a method is, in turn, characterized in that it comprises a plate for freely supporting the intermediate panel intended to come into contact with the underside of the mandrel, said plate being kept away from it. ci, to proceed first to the folding of the panels adjacent to the intermediate panel against the lateral faces of the mandrel, then bring said intermediate panel closer to the underside of the mandrel. Such a machine therefore has the result of rigorously matching the fold lines made beforehand on the flat cuts with the edges of a mandrel giving the final shape of the body which it is desired to obtain.

Such a process has many drawbacks outside of the production rates, which are necessarily limited by the numerous successive phases of the process; in addition, when the side panels are folded relative to the intermediate panel, the cutout is delivered to itself, without positive support, which can only be done at a reduced rate at the cost of particularly sophisticated adjustments and therefore, a expensive machine construction.

Another major drawback of the process in accordance with the prior art is that it is necessary to deposit lines of glue from below since, by hypothesis, the cut arrives with the useful face facing downward from the forming machine; we know perfectly well that the deposit of glue by spraying upwards creates numerous incidents due to dripping and other untimely fall of adhesive on the machine or on the injectors. In addition, these incidents and faults are aggravated by the presence of dust and cardboard fibrils; generally in this type of bonding, it is not possible to use cold adhesives which, by hypothesis, are extremely fluid and very quickly clog the injectors. However, it is well known that the boxes only glued with glues of the "hot melt" type are extremely sensitive to outside temperatures, which considerably limits transport due to climatic conditions for example.

To overcome all these drawbacks, while retaining the advantages provided by the use of the "wrap around" technique, a new method is proposed according to the invention for mounting a box with polygonal cross section from a flat blank of corrugated cardboard or the like comprising a set of panels connected to each other by first fold lines parallel to each other, flaps arranged on either side of the panels and connected to these by second lines fold perpendicular to the first, and a junction tab from the free edge of one of the end panels to which it is connected by a fold line parallel to the first, to form by gluing, the junction of the box after being rolled up all of said panels around a mandrel of polygonal section comprising on the one hand, at least a plurality of longitudinal faces extending in the axis of the mandrel, at least one of which horizontal upper face and side faces of the same length which are attached to it symmetrically on either side of a vertical plane passing through the axis of the mandrel forming at their intersections longitudinal edges and on the other hand, at least one transverse face - that is to say perpendicular to the axis of the mandrel -, attached to the preceding ones by forming at their intersections vertical and transverse edges, means for gluing and folding the flaps situated on the same side of the panels being provided to form the bottom of the body when they are folded over the transverse face of the mandrel, which, displaced longitudinally in the direction of advance of the cutouts and parallel to itself, ejects the assembled body from the mandrel which can then receive a new cutting; this process is remarkable in that each cut is first extracted from a food store, its face corresponding to the external face of the box being turned upwards, then transferred horizontally, following a rectilinear trajectory at constant speed, reduced and controlled, towards the mandrel on which it comes to dock precisely before the body is formed, one of the panels then exactly coinciding with the horizontal upper face of the mandrel, by means also providing positive maintenance of said cutout , requiring no additional lateral guidance, and in that the transfer at reduced constant speed is used to deposit with precision lines of glue at least on the junction tab and on two bottom flaps necessary for mounting the body around the mandrel and / or, where appropriate, for depositing with precision ink or the like making it possible, for example, to transplant imp recession.

It can therefore be seen that, according to the invention, in addition to the advantage of easy transport and storage of the flat blanks, all the drawbacks of the prior art have been practically eliminated. Insofar as the blank is supplied here from above the forming mandrel, it is possible to arrange the glue guns in such a way that the glue is deposited downwards, eliminating and in any case considerably reducing all the defects listed above. It is also understood that the maintenance of the guns is much easier, since the assembly is located above the machine, that is to say that it is easily accessible; in addition, this arrangement allows a visual check of the glue lines on the top of the cutout on the printed side of the mounted box. Finally, this provision, particularly advantageous pistols, allows the industrial use of cold glue, as has been said above.

According to another essential characteristic of the process of the invention, it is planned to use an extensible mandrel; in this sense and according to a first characteristic, the mandrel can be separated by a vertical plane into two left and right parts in order to be able to modify the base section of the boxes by one of its dimensions, by moving transversely and parallel to itself, one of the parts of the mandrel, the other being kept fixed. According to another characteristic which can be used simultaneously or not, the same mandrel can be separated by a horizontal plane into two upper and lower parts, so as to modify the base section of the boxes by the other of its dimensions, this time moving vertically and parallel to itself the lower part of the mandrel, the upper part remaining fixed. Finally, according to a last essential characteristic of the process, the mandrel is mounted in cantilever and embedded in the machine; in this way and according to the method, provision is made to vary the useful length of the mandrel by longitudinally moving its embedding point towards the rear, that is to say by keeping the free front portion fixed, serving as said it, of ejector; in this way, it is possible to adjust the machine very quickly to process boxes with different heights.

Other characteristics and advantages will emerge more clearly from the description which will be given of the process according to the invention and of a machine implementing it, given by way of nonlimiting example with reference to the drawings in which: 1 schematically represents the main steps of a box forming line according to the method.

- Figure 2 is identical to Figure 1, but in top view.

- Figure 3 shows a variant of the receiving store a stack of flat cuts feeding from below a forming machine in accordance with the invention. FIG. 4 represents another variant of the magazine receiving a stack of cutouts placed on the edge supplying a case-forming machine according to the invention. Figures 5 to 8 show the successive stages of the formation of a box around a mandrel according to the invention from a starting position until pressurization and bonding of the joining lug.

- Figures 9 to 11 schematically show, in top view or in side view, the main phases of folding the flaps constituting the bottom of the boxes, once the joining has been carried out on a mandrel according to one invention.

- Figure 12 is a representation in longitudinal half section and in elevation of a polygonal box forming line with square or rectangular section showing the functional and characteristic elements of one invention

- Figure 13 shows the same machine as Figure 12 but in full top view, with the exception of the upper chassis elements. - Figure 14 corresponds to the machine shown in Figures 12 and 13, but in front view, on the side of the outlet of the boxes. For reasons of readability of the figure, the two actuators have not been shown for pressurizing the large bottom flaps. With reference to FIGS. 1 to 4 of the drawings, the main functional stages of the process according to the invention will now be described.

The blanks 1 are stored flat in vertical stacks, printed side up, in accordance with step A of FIG. 1. It will be observed that this storage is particularly easy, insofar as the stack of cutouts has no excess thickness, thus providing it with great stability; this stack of cutouts 1 is then, in accordance with the horizontal arrow a, transferred to the magazine 2 of the assembly line, in accordance with a first variant (figure 1-B); the machine is supplied here by the top of the stack of the magazine 2 which is therefore regularly leveled horizontally, according to the arrow b in step B. The depilation is here carried out for example by a driving pusher, according to the arrow ç_j_ the upper cutout towards the transfer zone C of FIG. 1. According to the invention, this transfer zone allows the cutout 1 to be driven horizontally and rectilinearly in the longitudinal axis of the machine, in order to reach the upper face of the mandrel 3 on which it rests before folding. It should be noted here that the cutout 1, between the unstacking zone and its arrival on the mandrel has never ceased to be positively maintained, both in the horizontal plane and in the vertical plane. According to a main arrangement of the invention, the transfer time between the magazine 2 and the mandrel 3 will advantageously be used to deposit the lines of glue and / or if necessary, the ink or the like making it possible for example to make printing subcultures by means of glue guns 4 and printheads 5 arranged above the cutouts 1; depositing glue and / or ink jets are done vertically downwards, with all the happy consequences that have already been described in detail.

According to the method, a flat cut which leaves the transfer zone Ç_ is then subjected to the succession of the following main steps: a) bringing the cut into horizontal abutment so that one of the panels comes into coincidence with the face upper part of the mandrel, then folding along pre-folding lines around the upper horizontal edges of the mandrel, joint panels of the panel coinciding with the horizontal upper face of the mandrel in order to fold them down around the lateral faces (phase D, figure 1); b) folding of the last panel on the lower part of the mandrel (phase E, figure 1); c) folding and pressurizing the junction tab and folding and pressurizing the bottom flaps, ejecting the box in accordance with arrow d (phase E, FIG. 1); d) the box is taken up by a reversing conveyor 6, pivoting in a vertical position, upper flap at the top; then by means of a last conveyor 7, the box is directed to its place of filling.

Figures 1 and 2 perfectly illustrate the characteristics of the invention, namely the handling of a flat cut 1 in a feed magazine 2, brought at constant speed on the mandrel 3, so that the lines folding the reference panel exactly coincide with the longitudinal edges of the mandrel 3; this docking is done without change of altitude, in perfect synchronism between the box ejector mounted on one side and the introduction pusher on the other.

By way of example in FIGS. 3 and 4, the destacker 2 used in FIGS. 1 and 2 can be replaced by other systems that are perfectly mastered by one skilled in the art; in FIG. 3, the destacker 2 is a destacker from the bottom, that is to say that the cutout 1 which will be introduced according to the machine is taken from below the stack and no longer from above, as previously , thanks to a suitable pusher 8 schematically represented in FIG. 3. Another variant of destacker is given in FIG. 4 consisting in storing the stacks of blanks, no longer flat in the store, but on edge; a suction cup actuator 9 positions, in a simple rotation f _. , the cut horizontally, ready to be introduced into the forming machine.

With reference to FIGS. 12, 13, 14, and according to another object of the invention, a machine will now be described implementing the method according to the invention which has just been detailed.

The machine 10 for mounting a box 11 of polygonal section from a flat cut 1 in corrugated cardboard or the like, comprising, as we have seen, a set of panels 12,13,14,15 forming the lateral faces of the assembled box, connected to each other by first fold lines 16, 17, 18 parallel to each other and on either side of said panels of flaps 19 to 26, connected to the same panels 12 to 15 by second fold lines 27 to 30 perpendicular to the first and a junction tab 31 coming from the free edge of one of the end panels 12 to which it is connected by a fold line 32, parallel to the first 16,17,18, to form by bonding or any other equivalent means, the joining of the body 11; the machine 10 comprises at least the following zones:

- a unstacking zone B making it possible to extract, one after the other, the blanks 1 which are stacked flat in a magazine 2; - a transfer zone C of the blank 1;

- A forming zone D of the body 1 around a mandrel 3; an ejection zone E and evacuation F of the body 11 thus mounted. The mandrel 3 of polygonal section allowing conventionally to produce cases comprising at least 3 lateral faces is, according to the invention, constituted at least by a plurality of longitudinal faces, extending along its longitudinal axis, including at least one upper horizontal face 35 and, where appropriate, a lower face 36 and lateral faces 37, 38 of the same length which are attached to them symmetrically on either side of a vertical plane passing through the axis of the mandrel 3 by forming longitudinal edges higher 39.40 and lower 41.42; the mandrel 3, embedded on one side in the transfer zone C as will be said later, has on its free front part a transverse face 43 perpendicular to the axis of the mandrel and attached to the faces longitudinal by forming transverse edges 44,45,46,47 at their intersections.

Of course, the machine 10 is provided with conventional means for gluing, folding and pressurizing the panels and the flaps of the box which will be specified later in the description.

According to the main characteristic of the invention, the transfer zone C of the machine 10 comprises at the entrance, that is to say on the side where the cutout 1 pushes next ç out of the supply magazine 2, two first identical rolls 50, 51, held tangent and superimposed, their axis in the same first vertical plane PI perpendicular to the direction of advancement of a cut 1 arriving flat from the unstacking zone B on the side of its bottom flaps 23 to 26 (Figure 13) to be introduced horizontally for example by a conventional pusher 8, between said first rollers 50,51 one of which is driven in constant and controlled rotation, thus driving the other roller at the same speed in one direction opposite; when the cutout 1 correctly positioned, as will be said later, at the outlet of the destacker 2, is supported between the rollers 50, 51, this takes on a constant speed and it must be held horizontally during its stroke; for this purpose, a system of longitudinal slides has been provided, consisting, as will be said below, of two yokes 52, 53 mounted side by side, so that their upper planar faces together form a vertical bearing face of guide to maintain, during its movement, the cutout 1 in the horizontal plane on which it progresses rectilinearly and at constant speed until touching, on their tangent lines, two second rollers 54,55, identical to the first 50,51 and also superimposed in the same second vertical plane P2 perpendicular to the direction of advancement of the cuts; as for the first rollers, the second are kept tangent and driven in rotation, in the same direction and at the same speed as the first; thus arranged, the first and the second rollers have the same horizontal plane of symmetry constituting the transfer plane 56 on which the blank 1 moves.

According to a general operation of the machine according to the invention, the movement of the blank 1 on the transfer plane 56 is established in three main phases: driving by the first rollers 50, 51 and rectilinear movement of the blank 1 on the transfer plan 56;

- supported by the second rollers 54,55 and simultaneous drive by the first and second rollers;

- release of the first rollers 50,51 and docking on the mandrel 3 on which the blank 1 finally comes to rest, after having been released from the grip of the second rollers 54,55.

It will be noted in passing that at right and above the transfer plane 56, the glue guns 4 and / or the print heads 5 are placed on a horizontal ramp 57 arranged above and across the transfer plane 56, so that they can be aligned with the suitable parts 23, 25, 31 of the blank 1 which are intended to receive, at reduced speed, jets of glue 58 and / or ink jets 59 (figure 2).

According to another characteristic of the invention, it is provided that at least the upper rollers 50, 54 of the first and second rollers are provided with pressure rollers 60, which will normally all be identical, except having to adjust the relative speed unnecessarily. drive of the sets of rollers, chosen from a flexible material advantageously anti-slip and mounted concentrically on each roller, in sufficient number and distance to drive, without sliding, at constant speed, the cutout 1 over the entire surface of the transfer plane 56.

Of course, according to a preferred embodiment of the machine 10, pressure rollers 60 will be mounted on the four rollers arranged in such a way that the rollers equipping the upper rollers are tangent to the rollers equipping the lower rollers. It should be noted here that, without being compulsory for the correct operation of the machine transfer system, the rollers constitute an advantage of the device in that they create, between the superposed rollers, a space facilitating the engagement of the cutouts 1 to 1 ' entry and preserving the integrity of the lines of glue 58 and / or impressions 59 at the exit since the contacts between the driving rollers and the cutout are limited to only the contact zones of the pressure rollers 60; in addition, such an arrangement makes it possible to pass into the system cuts of lower quality or having some defects due to storage or to humidity for example. Finally, the pressure rollers 60 constitute more precise cutters and, provided that the cutouts are correctly positioned in the feed magazine 2, it is ensured to transfer them to the mandrel 3 with excellent precision; the magazine 2 is, in this respect, provided with two vertical stops 61.62 respectively perpendicular and parallel to the direction of introduction of the blanks 1, making it possible to precisely position the blanks at the entrance to the machine, as has been said . According to a fundamental characteristic of the invention, the mandrel 3 is mounted longitudinally in cantilever at the exit from the transfer plane 56, in such a way that embedded by its rear face, its longitudinal axis is parallel to the direction d advance of the cutouts 1 and its upper longitudinal edges 39.40 coincide respectively with the direction of the first fold lines 16.17 of the panel 13 in front, in the forming zone D, coincide with the upper face 35 of said mandrel 3 (FIG. 13 ). According to a particularly advantageous embodiment of the machine 10, the rear face of the mandrel 3 is secured to the longitudinal slides 52, 53, so that the upper face 35 of the mandrel 3 is at the same level than the transfer plan 56 (Figures 12 and 13).

We understand all of the advantage of the assembly which has just been described, allowing the mandrel 3 to be located directly in horizontal continuity of the transfer plane 56, while benefiting from simple mounting on the machine 10; for this purpose, the two vertical yokes 52, 53 used to form the two horizontal slides of the transfer zone C are extended towards the front to form the two support beams of the mandrel 3 which is thus cantilevered; this assembly is particularly advantageous in that it allows to release all the volume around the mandrel 3, which will facilitate the work of forming the box and then its ejection. On the other hand, it will be understood that, subject to moving together, horizontally and parallel to themselves in the direction of advance of the blanks 1, the two output rollers 54, 55, thanks to screw actuators 63 , 64 can be easily automated if necessary, it is possible to adjust the useful distance between the head of the mandrel 3 corresponding to the free transverse face 43 which remains fixed and the output of the transfer zone, to form boxes of heights different; provision is therefore made to move the output rollers 54.55 horizontally over a maximum distance corresponding to the difference in the heights of the boxes which are to be mounted by the machine 10. This horizontal movement of the output rollers 54.55 leads to providing in the two yokes 52, 53 forming the supports of the transverse slots 65 allowing the horizontal displacement of the lower roller 55 in the direction of advance of the cutouts.

It goes without saying that the spacing between the input rollers 50,51 and the output rollers 54,55 is at most equal to the width of a flat cut 1 corresponding in fact to the body height increased by two widths of its flaps; moreover, we will arrange so that this spacing is always greater than or equal to half the width of the cutout 1, in order to preserve a time of transfer sufficient for gluing and / or printing.

With reference to FIGS. 12, 13 and 14, a machine 10 will now be described, by way of nonlimiting example, making it possible to implement the method, according to the invention, for mounting boxes of square or rectangular base section .

Such a machine is characterized in that the mandrel 3 is formed of two sets 70, 71 symmetrical with respect to the vertical plane passing through its longitudinal axis; each set 70,71 determines a volume delimited by at least two upper 72 and lower 73 horizontal elements, providing with their respective symmetry the upper 35 and lower 36 faces of said mandrel 3, and at least one vertical face determining a lateral face 37,38 of said mandrel 3, normally and advantageously of the same length as the horizontal elements 72, 73 to which it is attached (FIG. 5 and FIG. 12). It will be seen later, in an even more advantageous variant, that the lateral faces 37, 38 of the mandrel 3 can be extensible in the vertical plane, which then requires that said lateral faces be cut into two vertical faces 74.75.

The horizontal elements 72,73 form, with the vertical element or elements 74,75, two rectangular dihedrons whose edges 39,41 coincide with the fold lines 17,18 between two successive panels 12,13 and 14,15.

According to a variant of the mandrel making it possible to mount boxes with cut sides and particularly boxes with eight sides, provision is made for the intersections between the horizontal elements 72,73 and vertical elements 74,75 to be made by means of elements of the same length, but inclined, for example by 45 ° to form the cut angles whose edges will coincide, in the same way, with the corresponding fold lines of the eight-sided box that it is desired to obtain.

According to another characteristic of the invention, provision is made to make the two assemblies 70, 71 forming the mandrel 3 transversely displaceable, as indicated by arrow L in FIG. 13. By this transverse displacement of the assemblies, carried out parallel to themselves in the horizontal plane, it is clear that we can thus receive boxes of different lengths, without 'It is necessary to change the mandrel 3. It suffices, in fact, to mount one of the sets 71 movable relative to the other 70 which remains fixed and integral with the chassis of the machine; the mobile assembly is, for its part, mounted on two identical horizontal slides 76, providing it with sufficient vertical rigidity and a possibility of transverse displacement to adjust the length L of the boxes 11.

It is obvious that the transverse displacement according to the arrows L in FIG. 13 of the movable symmetrical assembly 70 can be obtained either by screw actuators (not shown in the drawings), or by any other system which can be, in all cases, automatically controlled. According to another important claim of the invention, the vertical face 38 of each symmetrical assembly 70,71 can be separated into two superimposed parts high 74 and low 75, and it is possible to adjust the spacing by screw actuators possibly automated, while keeping the parallel edges 39,41 or 40,42 parallel; the upper parts 74 remain fixed and at the same altitude in the vertical displacement which is carried out, in addition, in the same way for each set 70, 71 and this, with the aim of being able to modify, in accordance with the arrows 1 of the figure 12, the width of the base section of a box 11.

With reference to FIGS. 5 to 8, showing during step D of the process the succession of the folding and pressurization phases of a cutout 1 around the mandrel 3 in order to form a box 11, we will detail below the operation of the folding means.

On leaving the transfer zone C, the cut to flat 1 approaches the upper surface 35 of the mandrel 3 on which it rests by its panel 13, the fold lines 16,17 coming exactly in coincidence with the edges 39,40 of the mandrel 3, in direct application of the method according to the invention . To this end, as soon as the cutout 1 has left the transfer zone C, it is taken up by cleats 82 (shown diagrammatically in FIG. 13) coming to bear on the small rear side 80 of the connecting tab 31, in order to bringing the short front side 81 of said tab into abutment 83 (shown diagrammatically in FIG. 13), putting the fold lines 29 of bottom flaps 24 in alignment with the upper transverse edge 47 of the mandrel 3.

At this instant, the relative position of the cutout and of the mandrel is in accordance with FIG. 5. Two pressers with lateral flaps 84.85 simultaneously fold and press the dividing panels 12.14 in horizontal support 13 against the lateral faces 37.38 of the mandrel 3 (FIG. 6); at this time, the fold lines 16,17 are exactly in coincidence with the upper longitudinal edges

39.40 of the mandrel 3, resulting from the precise positioning due to the transfer system, according to the invention; the forming step is schematically represented by FIG. 6.

The pressers 84, 85 remaining in the lateral support position, in accordance with the previous step, it is then necessary to put the last panel 15 horizontally which until then was in alignment with the panel 12. To do this, it provision is made for the left actuator 84 to be equipped at its free end with a linear actuator 86 mounted substantially perpendicular to the plane of the actuator 84, so that the linear deployment of the presser pivots the panel 15 around the stop lower longitudinal 41, along the fold line 18 between the panels 14 and 15 of the blank 1; simultaneously and even a little before, the auxiliary actuator 87 comes, in accordance with the diagram of FIG. 7, to fold down the joining tab 31 comprising a line of glue 58 so that, during the folding of the panel 15 by the actuator 86, said panel 15 comes to bear on tab 31 when the arm of actuator 86 is fully extended. At this instant and in accordance with FIG. 8, a pressurizing tool 88 comes, by rotation, to compress the panel 15 to the level of the tab 31 comprising the line of glue 58, in order to apply them against the lower horizontal face 73 of the mandrel 3 if it is expandable, or against the face 36, if the mandrel is in one piece. During the pressurizing movement of the tool 88, the arm of the linear actuator 86 was removed and the actuator 87 for bending the tab 31 was released around the stop 42 of the mandrel 3, in order to allow the final pressurization by the actuator 88; of course, during the pressurization of the actuator 88, the two actuators 84, 85 are released by vertical rotation, thereby freeing all the faces of the body 11 thus joined.

According to another important characteristic of the machine, the free end of each symmetrical assembly 70, 71 at the front of the mandrel 3 is formed by one or two superposed parts 90, 91 depending on whether one considers a mandrel expandable towards the bottom according to 3. or not, providing together a vertical bearing surface 43 perpendicular to the axis of the mandrel 3 whose intersections with the upper 72 and lower 73 horizontal elements form transverse edges 45, 47 around which the large ones are pivoted external bottom flaps 24,26 and whose intersections with the lateral face of the mandrel 37,38 form a vertical edge 44,46 around which is pivoted a small inter bottom flap 23,25. To this end and in accordance with FIG. 9, the small flaps 23.25 comprising the lines of glue 58 are folded by the action of two push cylinders 92.93, the large flaps 24.26 remaining in the extension respectively of the panels 13 , 15. In accordance with FIG. 10, a first pre-folding of the large lower panel 26 is then carried out by means of an actuator 94 which prepositioned against the transverse face of the mandrel 3 said flap 26; finally and according to a characteristic of the invention, there is carried out, in accordance with FIG. 11, a vertical folding of the flap 24 corresponding to the reference panel 13 along the folding line 29 by means of one or two pushers 95 of horizontal axis coming to press simultaneously the two large flaps 24,26 in order to create a perfectly flat bottom for the body 11.

Finally, once formed, it must be in accordance with step E ejected from the mandrel 3 which is made possible by the longitudinal displacement of the free face 43 of the mandrel which serves as longitudinal ejector in the same manner as exposed in the earlier patent already cited; according to a particular embodiment of the invention, this ejector member consists of a longitudinal pusher 96 whose fixed surface is nevertheless chosen so that it is effective whatever the expansion position of the mandrel 3 when the latter is extendable .

According to a last characteristic of the invention, provision is made to arrange the actuating means and the longitudinal supports 97 of the ejector 96 on the inner part of the fixed assembly 70 although according to less advantageous embodiments it is possible to make it integral with the mobile assembly.

Those skilled in the art are able to make all the useful modifications to transform all of the mechanisms detailed in the previous description to adapt it to other body sections to be assembled in accordance with the method.

Claims

1 - Method for mounting a box with polygonal section from a flat cut in corrugated cardboard or the like comprising a set of panels connected to each other by first fold lines parallel to each other, flaps arranged on either side of the panels and connected to them by second fold lines perpendicular to the first, and a junction tab coming from the free edge of one of the end panels to which it is connected by a fold line parallel to the first, to form by gluing, the junction of the body after having wound all of said panels around a mandrel of polygonal section comprising on the one hand, at least a plurality of longitudinal faces, extending in the axis of the mandrel, at least one horizontal upper face and lateral faces of the same length which are symmetrically attached to it on either side of a vertical plane passing through the axis of the mandrel by forming longitudinal edges at their intersections and, on the other hand, at least one transverse face -that is to say perpendicular to the axis of the mandrel-, attached to the preceding ones by forming vertical and transverse edges at their intersections, means for gluing and folding the flaps located on the same side of the panels being provided to form the bottom of the body when they are folded over the transverse face of the mandrel, which is displaced longitudinally, that is to say in the direction of advance of the cuts, and parallel to itself, ejects the assembled box from the mandrel which can then receive a new cut, a process characterized in that each cut is first extracted from a food store, its face corresponding to the external face of the body being turned upwards, then transferred horizontally, following a rectilinear trajectory at a reduced and controlled constant speed, towards the mandrel on which el it comes to dock precisely before the body is formed, one of the panels then exactly coinciding with the face horizontal upper of the mandrel, by means also providing positive maintenance of said cut, requiring no additional lateral guidance, and in that the transfer at reduced constant speed is used to precisely deposit lines of glue at least on the connecting tab and on two bottom flaps necessary for mounting the box around the mandrel and / or, if necessary, for depositing with precision, ink or the like making it possible, for example, to transplant impression. 2 - Method according to the preceding claim characterized in that the adhesive removal is done vertically and downward, allowing easy maintenance of the guns, visual control of the adhesive lines and the industrial use of cold glue. 3 - Method according to the preceding claim characterized in that the mandrel being separable by a vertical plane into two left and right parts to modify by one of its dimensions the base section of the boxes, it is moved transversely and parallel to itself , one part of the mandrel the other remaining fixed. 4 - Method according to the preceding claim characterized in that the mandrel being separable by a horizontal plane into two upper and lower parts to modify by the other of its dimensions the base section of the boxes, it is moved vertically and parallel to itself the lower part of the mandrel, the upper part remaining fixed. 5 - Method according to any one of the preceding claims characterized in that, to modify the height of the boxes, the useful length of the mandrel is adjusted along its longitudinal axis towards the rear, the transverse edges remaining fixed. 6 - Method according to any one of the preceding claims, characterized in that the forming from a flat cut leaving the transfer zone proceeds from the succession of the following main steps: a) horizontal abutment of the cutout so that one of the panels comes into coincidence with the upper face of the mandrel, then folding along pre-folding lines around the upper horizontal edges of the mandrel, of the party panels of the panel coinciding with the horizontal upper face of the mandrel to fold them down around the lateral faces, then b) folding of the last panel on the lower part of the mandrel, then c) folding and pressurizing of the junction tab, d) folding and pressurizing the bottom flaps e) ejection of the box. 7 - Method according to claim 6 characterized in that the total duration of the steps is equivalent to or slightly less than the transfer time of a cut from the unstacking area, to the forming area. 8 - Method according to any one of claims 6 or 7 characterized in that the folding of the bottom flaps according to step d is carried out according to the succession of the following phases: - folding of the small flaps corresponding to the internal flaps carrying the lines of glue - partial folding of the large lower flap (s) corresponding to the outer flaps of the bottom - simultaneous pressurization of all the large upper and lower flaps to obtain a flat bottom. 9 - Machine (10) for mounting a box (11) of polygonal section from a flat blank (1) of corrugated cardboard or the like comprising a set of connected panels (12,13,14,15) to each other by first fold lines (16,17,18) parallel to each other and flaps connected to said panels by second fold lines (27 to 30) perpendicular to the first, and a tab (31) from the edge free from one of the end panels (12) to which it is connected by a fold line (32) parallel to the first (12 to 15), to form by bonding, the junction of the body (11), machine comprising at least: - a unstacking zone B making it possible to extract one by one the blanks (1) stacked in a store (2), - a transfer zone C from the blank (1) to, - A forming area D of the body around a mandrel (3) of polygonal section comprising on the one hand, at least a plurality of longitudinal faces, extending along the longitudinal axis of the mandrel (3), of which at least one horizontal upper face (35) and lateral faces (37,38) of the same length which are symmetrically attached to it on either side of a vertical plane passing through the axis of the mandrel (3) forming ridges longitudinal (39 to 42) and on the other hand, at least one transverse face (43), perpendicular to the axis of the mandrel, attached to the previous ones by forming transverse edges (44 to 47), gluing means (4 ) and folding (92 to 95) flaps (23 to 26) located on the same side of the panels (12 to 15) being provided to form the bottom of the body (11) when they are folded down on the transverse face ( 43) of the mandrel (3) and, - An ejection and evacuation zone F of said mounted box 11, characterized in that the transfer zone C comprises at the entrance, two identical first rollers (50, 51) kept tangent and superimposed, their axis being in the same first vertical plane PI perpendicular to the direction of advancement of a cutout (1) arriving flat from the unstacking zone B, on the side of its bottom flaps (23 to 26), to be introduced horizontally, by a conventional pusher (8) for example, between said first rollers (50,51) one of which is driven in controlled rotation to advance the cutout (1) at constant speed, by taking vertical support on at least one longitudinal slide, and preferably two slides (52,53) mounted side by side, allowing to approach, at the exit, substantially on their line of tangency, two second rollers (54,55) identical to first (50,51) and also superimposed in the same second vertical plane P2, perpendicular to the direction of advance, kept tangent and driven in rotation in the same direction and at the same speed as the first rollers (50,51), the first and second rollers having the same horizontal plane of symmetry constituting the transfer plane (56) on which the cutout (1) moves according to the three main phases: a) drive for the first rollers (50,51), b) supported by the second rollers (54,55) and simultaneous drive by the first and second rollers, c) release of the first rollers (50,51) and docking on the mandrel (3) on which the cutout (1) comes to rest after release of the second rollers (54,55). 10 - Machine according to claim 9 characterized in that, in line with and above the transfer plane (56), are arranged glue guns (4) or print heads (5) which can be moved transversely over a horizontal ramp (57) to align them with the suitable parts (23,25) of the cutout (1) which can thus receive at low speed jets of glue (58) of any type including cold glue, or jets ink (59). 11 - Machine according to any one of claims 9 and 10 characterized in that, at least the upper rollers (50,54) of the first and second rollers are provided with pressure rollers (60) normally identical in advantageously flexible material, mounted concentrically on each roll in sufficient number and distance to drive without slipping, at constant speed, the cutout (1) pushed horizontally out of the magazine to the mandrel, leaving a space between the superimposed rollers, at least at the outlet of the transfer, to allow the glue lines to pass and / or not to alter the transplanting impressions and for better rectilinear guidance whatever the quality of the cardboard. 12 - Machine according to any one of claims 9 to 11 characterized in that the mandrel (3) mounted longitudinally overhang is such that, embedded by its rear face, its longitudinal axis is parallel to the direction of advance of the cutouts (1), its upper longitudinal edges (39.40) coincide with the direction of the first fold lines (16.17) of the panel (13) which must, in the forming zone D, coincide with the upper face (35) of said mandrel (3). 13 - Machine according to claims 11 and 12 characterized in that the rear face of the mandrel (3) is secured to the longitudinal slides (52,53), so that the upper face (35) of the mandrel (3) is at same level as the transfer plan (56). 14 - Machine according to any one of claims 9 to 13 characterized in that the two output rollers (54,55) of the transfer zone C can be moved together, horizontally and parallel to themselves in the direction of advance cuts through screw actuators 63,64) for example, which can be automated, over a maximum distance corresponding to the difference in the maximum and minimum heights of the boxes to be formed. 15 - Machine according to any one of claims 13 and 14 characterized in that the longitudinal slide and preferably the two slides (52,53) are formed by the extension towards the rear of the mandrel (3), the upper face (35 ) of said mandrel (3) thus being in the same plane as the upper face of the slides forming the transfer plane (56), transverse slots (65) provided in the slide support (s) (52,53) to allow movement horizontal of the output rollers (54,55) in the direction of advance of the cutouts (1). 16 - Machine according to any one of claims 14 or 15, particularly intended for mounting boxes (11) of square base section or rectangular possibly with cut angles - said to be eight-sided -, characterized in that the mandrel (3) is formed by at least two sets (70,71) symmetrical with respect to the vertical plane passing through its longitudinal axis, each determining a volume delimited by at least two horizontal elements, upper (72) and lower (73), providing with their symmetrical respectively the upper (35) and lower (36) faces of said mandrel (3), and at least one vertical face (74,75 ), determining the lateral face (37,38) of said mandrel (3), normally of the same length as the horizontal elements (72,73) to which it is directly attached to form at their intersections two rectangular dihedrons whose edges (39,41 ) coincide with the fold lines (17,18) between two successive panels (13,14) and (14,15) or indirectly by means of elements of the same length but inclined, for example by 45 °, to form cut angles the edges of which coincide with the fold lines of an eight-sided box for example, and in that one assembly (70) is fixed and the other (71) movable transversely, actuated by means making it possible to modify by an L of its dimensions, the base section of the boxes (11). 17 - Machine according to claim 16 characterized in that the vertical face (38) of each symmetrical assembly (70,71) is in two superimposed parts, high (74) and low (75), the spacing of which can be adjusted while keeping the parallelism of the edges (39,41), the upper parts (74) remaining fixed and at the same altitude in the vertical displacement which is the same for each assembly in order to allow the other to modify 1. of its dimensions, the base section of boxes (11). 18 - Machine according to any one of claims 16 or 17 characterized in that the free end of each symmetrical assembly (70,71) is formed of one or two superimposed parts (90,91) together providing the surface d vertical support (43) perpendicular to the axis of the mandrel (3), the intersections of which with the horizontal upper (72) and lower (73) elements form transverse edges (45,47) around which the large external bottom flaps (24,26) are pivoted and whose intersections with the lateral face of the mandrel form a vertical edge ( 44,46) around which is pivoted a small internal bottom flap (23,25). 19 - Machine according to any one of claims 9 to 18 characterized in that the free transverse face (43) of the mandrel (3) serving as an ejector is supported by one of the two fixed (70) or mobile (71) assemblies ), and preferably the fixed assembly (70), and has a sufficient surface to constitute a longitudinal pusher (96) in all the horizontal and / or vertical expansion positions of the mandrel (3).