EP3224039B1 - Method and device for correcting the position of a folded cut-out in a folding-gluing machine - Google Patents

Description

The present invention relates to the field of the manufacture of packaging, including packaging made from sheets or strips precut, including paper cuts, plastic or cardboard, whether flat, corrugated or mixed.

In particular, the present invention relates to the machine or the module which makes, from a blank or a cardboard cut already grooved, on the one hand the folding of two lateral flaps that fall back in the direction of a central assembly line, with a partial overlap of the outer edge of these flaps, and secondly the gluing of these two parts in the overlap zone for their subsequent maintenance in the folded position which has been imposed by the machine. Such a machine is called folder-gluer.

State of the art

Many machines of the prior art perform these combined folding-gluing operations, along a path that follows the longitudinal axis of the folder gluer. During these processing operations of each carton blank, positional deviations of the two flaps are encountered once they are folded and glued, relative to their desired position, whether due to a deflection of the elements. movable of the machine, and / or due to an offset positioning of all or part of the cut relative to the machine during its processing and / or because of a cut that has geometric characteristics slightly different from the model cardboard cutting ideal.

A cutout 10 is flat (see Fig. 1 ) a general shape of rectangle with two sides of greater length, forming the front edge 11 for the side that first enters the folder-gluer machine, and the rear edge 12 for the side that enters the last in the folder-folding machine. gluer. When advancing the cut in the folder-gluer machine, according to the direction and the direction of the arrow A, this front edge 11 and this rear edge 12, which are parallel to each other, are generally orthogonal to the longitudinal axis XX 'of the folder-gluer. The two lateral sides of smaller length define the right edge 13 and the left edge 14 which are parallel to each other and to the longitudinal axis XX 'of the folder-gluer. The right edge 13 is the lateral side which is located to the right of the longitudinal axis of the folder-gluer, and the left edge 14 is the lateral side which is located to the left of the longitudinal axis XX 'of the folder-gluer. The right and left edges 13, 14 have a cut along their two end portions so as to define a right leg 13a and a left leg 14a in the central portion of the right and left edges 13, 14.

Two longitudinal lines represented in dotted lines correspond to the fold lines, materialized by the right longitudinal groove 15 and the left longitudinal groove 16, between which is delimited the central flap 19. Between the right groove 15 and the right edge 13, there is the right flap 17 and Between the left longitudinal groove 16 and the left edge 14, there is the left flap 18.

The Figs. 2 and 3 represent the blank 10, after folding and folding of the two flaps 17 and 18 one on the other, and after bonding between the right leg 13a and the left leg 14a, in an ideal conformation. In the other cases of cutting, the left leg 14a is sticking directly on the flap 17 at the right edge 13. In this situation, the right side 15 'of the folded-glued cut 10' is obtained at the location of the right longitudinal groove 15, and the left side 16 'of the folded-glued cut 10' is obtained at the location of the longitudinal longitudinal groove 16. In this case (see more precisely Fig. 2 ), the right edge 13 and the left edge 14 are spaced apart from each other, at the cutouts, a gap Greef, forming a reference gap, a predetermined value and constant along the cuts. So on the Fig. 2 , the same value Greef is found at the location of the front edge 11 and the location of the trailing edge 12.

Two main positioning anomalies of the two lateral flaps 17 and 18 can in particular be distinguished. A first anomaly of positioning of the two lateral flaps, called gap, corresponds to a too large spacing between the right and left edges 14 of the two flaps 17, 18 folded and glued: a representation of this first anomaly is visible on the Fig. 4 , with a gap G 'forming a larger gap than the greek.

A second anomaly of positioning of the two lateral flaps 17, 18, called fishtailing, corresponds to a defect of parallelism between the edges 13 and 14 of the two lateral flaps 17, 18 folded and glued, most of the time accompanied by the same lack of parallelism between the sides 15 'and 16'. A first configuration of this second anomaly is visible on the Fig. 5 in this case, the edges 13 and 14 converge towards the front edge 11 so that they define a smaller gap G1 (and possibly negative) between the front ends of the edges 13 and 14 that the gap G2 defined between the rear ends of the edges 13 and 14. In this case of fishtailing rear or open fishtailing, an angle α1 between the edges 13 and 14 is measured since the back edge 12. A second configuration of this second anomaly is visible on the Fig. 6 in this case, the edges 13 and 14 are divergent in the direction of the front edge 11 and converge towards the rear edge 12, so that they define a gap G1 larger (and possibly negative) between the front ends of the edges 13 and 14 that the gap G2 defines between the rear ends of the edges 13 and 14. In this case of front fishtailing or closed fishtailing, an angle a2 between the edges 13 and 14 is measured from the front edge 11. These two gap anomalies and fishtailing can meet simultaneously on the same cut of cardboard.

The document EP 1932658 describes a method and a folder-gluer machine which uses, at two successive alignment modules, an alignment rule whose orientation with respect to the longitudinal direction of the machine is modifiable, so as to allow, by this shift angular, which is imposed on one and then the other side of the folded cut, to make up at least a portion of the misalignment between the two right edges 13 and left 14. However, this solution can rectify d a systematic way the part of the misalignment that comes from the mechanical movements of the machine and not the shape or reaction to folding and other processing specific to each cardboard blank.

In the machines of the prior art, position sensors make it possible to detect these anomalies after treatment of the cut in order to identify and eject the packages concerned by anomalies exceeding a predetermined dimensional tolerance threshold. Also, in the machines of the prior art, the correction of the identified anomaly systematically goes through the modification of the setting of the moving parts of the machine, but does not take into account the deformation of the particular cut from its non-compliant position in the machine, improper folding, improper cutting (contour), or improper grooving.

Summary of the invention

An object of the present invention is to provide a method and a device for processing a cut in a folder-gluer for performing the correction of the position of the right and left flaps when folded one on the other, free limitations of known machines. Another object of the invention is to provide a method and a device for correcting the folded position of the right flap and / or the left flap of a cut, taking into account the individual situation of each cut. Another object of the present invention is to correct or not, on a case by case basis, the folded position of the right flap and / or the left flap of a cut, in order to obtain cutouts that are acceptable for most cases. Thus, a maximum of cuts can be preserved for the continuation of the treatment and to discard only one reduced number of cuts. In this way, material savings are realized since only few cuts are thus ejected from the machine to be discarded. Another object of the present invention is to ensure the reliable locking of the central flap during the control of the position and the possible correction of the position of the right flap and / or the left flap.

1. a) fourniture d'une découpe sensiblement plane comprenant un bord droit, un bord gauche, un bord avant, un bord arrière, une rainure longitudinale droite et une rainure longitudinale gauche, la rainure longitudinale droite et la rainure longitudinale gauche délimitant, avec le bord droit et le bord gauche au moins trois volets parmi lesquels un volet droit, un volet gauche et un volet central,
2. b) application de colle dans une zone du volet droit adjacente au bord droit et/ou dans une zone du volet gauche adjacente au bord gauche, de sorte que de la colle soit présente dans une portion de recouvrement entre le volet droit et le volet gauche,
3. c) pliage à 180° du volet droit autour de la rainure longitudinale droite en direction du volet central, et pliage à 180° du volet gauche autour de la rainure longitudinale gauche en direction du volet central,
4. d) fermeture du volet droit replié et du volet gauche replié qui se retrouvent l'un au-dessus de l'autre au moins dans la portion de recouvrement,
5. e) contrôle par détection optique de la position du bord droit et du bord gauche et comparaison de cette position effective avec une position prédéterminée de façon à déterminer un écart de position,
6. f) lorsque l'écart de position dépasse une valeur d'écart admissible, réalisation des sous-étapes suivantes avant la prise de la colle:
   • f1) blocage du volet central par sa face inférieure par des moyens de blocage fonctionnant avec une mise en dépression par vacuum de la face inférieure, et comprenant au moins une rampe équipée de buses orientées vers le haut et aptes à réaliser un vacuum, puis
   • f2) saisie de la face supérieure du volet droit replié et du volet gauche replié,
   • f3) correction de la position du volet gauche et/ou du volet droit,
7. g) mise en pression entre le volet droit et le volet gauche dans la portion de recouvrement jusqu'à la prise de la colle, et
8. h) relâchement du volet central, du volet droit et du volet gauche.

According to the invention, these objects are achieved in particular by means of a method of processing a cutout intended to form, after folding-gluing, a folded flattened box, according to claim 1, comprising the following steps:

1. a) providing a substantially planar cutout comprising a straight edge, a left edge, a leading edge, a trailing edge, a right longitudinal groove and a left longitudinal groove, the right longitudinal groove and the left longitudinal groove delimiting, with the edge right and the left edge at least three components including a right pane, a left pane and a central pane,
2. b) application of glue in an area of the right flap adjacent to the right edge and / or in a zone of the left flap adjacent to the left edge, so that glue is present in a covering portion between the right flap and the left flap ,
3. c) 180 ° folding of the right flap around the right longitudinal groove in the direction of the central flap, and folding 180 ° of the left flap around the left longitudinal groove in the direction of the central flap,
4. d) closing the folded right flap and the folded left flap which are found one above the other at least in the covering portion,
5. e) optically detecting the position of the right edge and the left edge and comparing this effective position with a predetermined position so as to determine a positional deviation,
6. f) when the position deviation exceeds a permissible deviation value, performing the following substeps before taking the glue:
   • f1) blocking of the central flap by its lower face by blocking means operating with a depression vacuum vacuum of the lower face, and comprising at least one ramp equipped with upwardly directed nozzles and able to perform a vacuum, then
   • f2) input of the upper face of the folded right flap and the folded left flap,
   • f3) correction of the position of the left pane and / or the right pane,
7. g) pressurizing between the right flap and the left flap in the covering portion until the adhesive is set, and
8. h) release of the central flap, the right flap and the left flap.

The use of blocking means operating with a depression under vacuum, allows to enter the central flap without damage and it is easy to activate or stop quickly.

Advantageously, the input of the upper face of the folded right flap and the folded left flap during step f2) is carried out respectively by at least one suction cup with vacuum, and in that the correction of the position of the left flap and / or of the right pane during step f3) is performed by moving the suction cup with vacuum. The use of suction cups with partial vacuum, allows to grasp and rectify the position of the folded right door and / or the folded left door, and this also without damage.

This solution has the advantage over the prior art of achieving the correction of the position of the folded flaps, only if the position control reveals that it is necessary and moreover with a correction adapted to the particular geometric situation of each cut considered.

Such a method can be implemented while the position of the cut, in the longitudinal direction of the folder-gluer, is substantially the same throughout the correction procedure. According to another embodiment, the method is implemented while cutting advances in the longitudinal direction of the folder-gluer, either continuously or by jerks.

• des moyens de pliage du volet droit et du volet gauche,
• des moyens de contrôle comprenant une détection optique de la position relative entre le bord droit et le bord
  gauche en direction transversale après pliage du volet droit et du volet gauche,
• des moyens de blocage du volet central comprenant au moins une rampe équipée de buses orientées vers le haut, J 2. aptes à réaliser une dépression par
  vacuum de la face inférieure du volet central de la découpe,
• des moyens de collage aptes à appliquer de la colle dans une zone du volet droit adjacente au bord droit et/ou dans une zone du volet gauche adjacente au bord gauche, de sorte que de la colle soit présente dans une portion de recouvrement entre le volet droit et le volet gauche,
• des moyens de correction de la position du volet gauche et/ou du volet droit, et
• des moyens de pression permettant de réaliser un contact sous pression entre le volet droit et le volet gauche dans la portion de recouvrement.

According to the invention, these objects are also achieved in particular by means of a device for correcting the position of a cut in a folder-gluer, according to claim 5, for a substantially plane cut comprising a straight edge, a left edge, a leading edge, a trailing edge, a right longitudinal groove and a left longitudinal groove, the right longitudinal groove and the left longitudinal groove delimiting, with the right edge and the left edge at least three flaps, among which a right flap, a left flap and a central flap, the device comprising:

• means for folding the right flap and the left flap,
• control means comprising an optical detection of the relative position between the right edge and the edge
  left in transverse direction after folding the right and left flaps,
• means for locking the central flap comprising at least one ramp equipped with upwardly directed nozzles, J 2, capable of producing a depression by
  vacuum of the lower face of the central flap of the cut,
• adhesive means capable of applying glue in an area of the right flap adjacent to the right edge and / or in an area of the left flap adjacent to the left edge, so that glue is present in a covering portion between the flap right and the left pane,
• means for correcting the position of the left pane and / or the right pane, and
• pressure means for making a pressure contact between the right flap and the left flap in the covering portion.

It is understood that such a device makes it possible to fold upwards both the right flap and the left flap, over the central flap which is well held, folding the folded right flap and folded left flap which is find one over the other at least in the overlap portion, the glue application, the control of the position of the right and left flaps, the possible realization of the correction of the position of the right flap, the left pane or both the right pane and the left pane, and maintaining the corrected position during the support between the right pane and the left pane in the covering portion until the glue. The order of operations mentioned above is not fixed, the glue can be installed before or after folding, before or after the position check, or before or after the possible correction.

The present invention also relates to a folder-gluer machine according to claim 13, equipped with a correction device as described in the present text.

Brief description of the figures

• la Figure 1 représente la projection d'une découpe de carton;
• les Figures 2 et 3 représentent cette découpe de carton, après pliage des volets latéraux, respectivement en vue de dessus et en vue depuis l'avant, selon la direction III de la Figure 2;
• les Figures 4, 5 et 6 sont similaires à la Figure 2 et représentent des configurations avec différentes anomalies de pliage;
• les Figures 7, 8 et 9 représentent le procédé de correction selon l'invention, respectivement pour les anomalies de pliage des Figures 4, 5 et 6;
• les Figures 10A et 10B représentent, respectivement pour une première position et pour une deuxième position, une vue depuis le dessous d'un mode de réalisation d'un dispositif de correction;
• les Figures 11A et 11B représentent, respectivement pour la première position et pour la deuxième position, une vue latérale partielle du mode de réalisation du dispositif de correction, respectivement selon la direction XIA de la Figure 10A et selon la direction XIB de la Figure 10B;
• la Figure 12 représente une vue selon la direction A des Figures 11A et 11B, montrant depuis l'arrière la partie supérieure du dispositif de correction de la Figure 10;
• la Figure 13 représente une vue latérale partielle du mode de réalisation du dispositif de correction selon la présente invention;
• la Figure 14 représente une vue selon la direction XIV de la Figure 13, montrant depuis le dessus une portion de la partie inférieure du dispositif de correction de la Figure 13;
• la Figure 15 représente une vue en coupe selon la direction XV-XV de la Figure 14;
• les Figures 16A et 16B représentent, respectivement pour la première position et pour la deuxième position, une vue de dessus selon la direction XVI de la Figure 13, montrant depuis le dessus une autre portion selon la présente invention de la partie inférieure du dispositif de correction de la Figure 13; et
• les Figures 17A et 17B représentent, respectivement pour la première position et pour la deuxième position, une vue latérale respectivement selon la direction XVIIA en Figure 16A et selon la direction XVIIB en Figure 16B, montrant depuis le côté la partie inférieure du dispositif de correction de la Figure 13.

Examples of implementation of the invention are indicated in the description illustrated by the appended figures in which:

• the Figure 1 represents the projection of a cardboard cutout;
• the Figures 2 and 3 represent this cardboard cut, after folding of the lateral flaps, respectively in plan view and in view from the front, according to the direction III of the Figure 2 ;
• the Figures 4, 5 and 6 are similar to the Figure 2 and represent configurations with different folding anomalies;
• the Figures 7, 8 and 9 represent the correction method according to the invention, respectively for the bending anomalies of the Figures 4, 5 and 6 ;
• the Figures 10A and 10B represent, respectively for a first position and for a second position, a view from below of an embodiment of a correction device;
• the Figures 11A and 11B represent, respectively for the first position and for the second position, a partial lateral view of the embodiment of the correction device, respectively in the direction XIA of the Figure 10A and according to the XIB direction of the Figure 10B ;
• the Figure 12 represents a view along direction A of Figures 11A and 11B , showing from behind the upper part of the correction device of the Figure 10 ;
• the Figure 13 represents a partial side view of the embodiment of the correction device according to the present invention;
• the Figure 14 represents a view according to the direction XIV of the Figure 13 , showing from above a portion of the lower portion of the correction device of the Figure 13 ;
• the Figure 15 represents a sectional view along the direction XV-XV of the Figure 14 ;
• the Figures 16A and 16B represent, respectively for the first position and for the second position, a view from above according to the direction XVI of the Figure 13 , showing from above, another portion according to the present invention of the lower part of the correction device of the Figure 13 ; and
• the Figures 17A and 17B represent, respectively for the first position and for the second position, a lateral view respectively in the direction XVIIA in Figure 16A and according to the XVIIB direction in Figure 16B , showing from the side the lower part of the correction device of the Figure 13 .

Examples of embodiment of the invention

We refer to the Fig. 7 illustrating the principle of the method for correcting a too large gap, namely with G '- Glef> 0. Thus, in this case, when after 180 ° folding of the right flap 17 and the left flap 18, a positional deviation is detected, namely the distance between the right edge and the left edge or gap, which is not in accordance with FIG. the admissible range, as for gap G 'of the Fig. 4 or from Fig. 7 , the following procedure is performed. After blocking of the central flap 19, the capture of the upper face of the right flap 17 folded by two suckers 21, 23 offset in the longitudinal direction and the gripping of the upper face of the left flap 18 folded by two suckers 24, 26 offset in the longitudinal direction are performed simultaneously.

For this purpose, the four suction cups 21, 23, 24 and 26 are lowered to come into contact with the folded right flap face 17 facing upwards and with the face of the folded left flap 18 facing upwards. The four suckers 21, 23, 24 and 26 being vacuumed during the capture, a safe grip of the right pane 17 in two locations and the left pane 18 in two locations is obtained. Then, as a function of the value of the lateral position deviation (G '- Greef) between the right edge 13 and the left edge 14, and the possible need to refocus this gap on a median longitudinal line of the cut (superimposed with the axis X-X '), identified by a control of the position of the right edges 13 and left 14, we will move laterally the right flap 17 or the left flap 18 or both the right pane 17 and the left pane 18 by moving a part or all the suction cups 21, 23, 24 and 26.

For this, the position of the left flap 18 and / or the right flap 16 is corrected by lateral displacement of the two suction cups 21, 23 of the right flap 16 and / or the two suction pads 24, 26 of the left flap 18 in order to change the distance between the right edge 13 and the left edge 14 to bring it back into the allowable range.

In a preferred embodiment, the two straight suckers 21 and 23, including the right front suction cup 21 and the right rear suction cup 23, are moved together. So, on the Fig. 7 to bring the right edge 13 of the axis X-X ', the pair of straight suckers 21, 23 is moved to the left. In the same way, preferably, the two left suction cups 24 and 26, comprising the left front suction cup 24 and the left rear suction cup 26, are moved together. So, on the Fig. 7 to bring the left edge 14 of the axis X-X ', the pair of left suction cups 24, 26 is moved to the left.

We refer to Figs. 8 and 9 , respectively illustrating the principle of the correction method for rear fishtailing or front fishtailing. Thus, in this case, when after 180 ° folding of the right flap 17 and the left flap 18, a positional error is detected in the form of a parallelism defect between the right edge 13 and the left edge 14, with a angle value α1 or α2 exceeding a maximum allowable value, it is in the presence of a result of folding not in accordance with the allowable range, and as for the Figs. 5, and 6 the following procedure is carried out.

• la saisie de la face supérieure du volet droit 17 replié par une seule ventouse droite avant 21, ou arrière 23 (la ventouse avant droite 21 sur les Figs. 8 et 9 sur lesquels la ventouse arrière droite 23 est représentée en traits pointillés car elle n'est pas mise sous vide de sorte qu'elle ne saisit pas l'arrière du volet droit 17), et
• la saisie de la face supérieure du volet gauche 18 replié par une seule ventouse gauche avant 24, ou arrière 28 (la ventouse avant gauche 24 sur les Figs. 8 et 9 sur lesquels la ventouse arrière gauche 26 est représentée en traits pointillés car elle n'est pas mise sous vide de sorte qu'elle ne saisit pas l'arrière du volet droit 17).

After blocking the central flap 19, simultaneously performs:

• the capture of the upper face of the right flap 17 folded by a single right suction pad 21, or rear 23 (the right front suction cup 21 on the Figs. 8 and 9 on which the right rear suction cup 23 is shown in dotted lines because it is not evacuated so that it does not grip the rear of the right flap 17), and
• the capture of the upper face of the left flap 18 folded by a single left suction cup 24, or rear 28 (the left front suction cup 24 on the Figs. 8 and 9 on which the left rear sucker 26 is shown in dotted lines because it is not evacuated so that it does not grip the back of the right pane 17).

For this purpose, the four suction cups 21, 23, 24 and 26 are lowered in right and left pairs, until coming into contact with the folded right flap face 17 facing upwards and with the face of the folded left flap 18 turned to the top. In the illustrated case, only the front suction cup 21 and 21 of each pair is placed under vacuum. Thus, when entering, we obtain a secure hold of the right pane 17 in one place (here at the front) and the left pane 18 in one place (here at the front). Then, depending on the value of the lateral position deviation between the right edge 13 and the left edge 14 (identified here by G1 - Gref at the front and G2-GRef at the rear, possibly taking into account the angle α1 or α2 measured between the right edge 13 and the left edge 14), and the possible need to refocus this gap on a longitudinal longitudinal line of the cut (superimposed with the axis X-X '), identified by a control of the position of the right edges 13 and left 14, we will angularly move the right flap 17 or the left flap 18 or both the right flap 17 and the left flap 18 by lateral displacement of one or both front suction cups 21 and / or 24. Alternatively, in a correction procedure not shown, this angular displacement is obtained by lateral displacement of one or both rear suction cups 23 and / or 26.

So, in the case of the Fig. 8 , the rear fishtailing is corrected by a lateral displacement of the front suction cups 21 and 24 towards the outer lateral sides of the bent cut, which are located on the same flap as the suction cup. So, as we see on the Fig. 8 , the right front suction cup 21 is moved towards the right side 15 ', namely to the right, and the left front suction cup 24 is moved towards the left side 16', namely to the left.

In the case of Fig. 9 , the front fishtailing is corrected by a lateral displacement of the front suction cups 21 and 24 towards the outer lateral sides of the folded cutout 10 which are located on the flap different from that on which the suction cup is concerned. So, as we see on the Fig. 9 , the right front suction cup 21 is moved towards the left side 16 ', ie to the left, and the left front suction cup 24 is moved towards the right side 15', namely to the right.

Thus, it is understood that when the detected positional deviation is a parallelism defect between the right edge 13 and the left edge 14, the angular position of the left flap 18 and / or the right flap 16 is corrected using, for the right pane 16 and for the left pane 18, a single sucker that is vacuumed to perform the seizure of the corresponding flap, and which remains under vacuum during its lateral movement, thereby changing the orientation of the right pane 17 and / or the left pane 18 to bring the right edge 13 and the left edge 14 substantially parallel to each other.

It will be understood that this maneuver for modifying the angular position of the right pane 17 or the left pane 18 or both of the right pane 17 and the left pane 18 also functions by partially evacuating and lateral displacement of one either of the front suction cup 21 (24) and the rear suction cup 23 (26): this entry at a single point of the flap concerned makes it possible to modify the angle formed between the edge of this shutter and the axis XX 'as far as this point of engagement of the flap by the suction cup is not placed in the middle of the length (extended along the axis XX' of the folder gluer).

In the case, not shown, where the folded blank 10 suffers from both a non-permissible gap and a non-permissible parallelism defect, the invention also makes it possible to act and rectify the two anomalies. In practice, the correction of the gap is effected by lateral displacement of the two suckers of each pair, right and left, the four suckers 21, 23, 24 and 26 being in engagement with the right and left flaps 17, according to the previous explanations of the Fig. 7 . Then, we stop the suction of one of the two suction cups of each pair to correct the fishtailing as explained above in relation to the Figs. 8 and 9 .

We refer to Figs. 10 to 13 for the upper part of the correction device. It finds the fact that the correction means comprise at least one suction cup for gripping the right flap 17 and at least one suction cup for gripping the left flap 18, the suction cups being oriented downwards, movable vertically and in the direction transverse and able to be subjected to vacuum. In particular, the correction means comprise a pair of straight suction cups 21, 23 and a pair of left suction cups 24, 26.

Also, for each pair of suction cups, a first suction cup 21 (24) is located at the front and a second suction pad 23 (26) is located at the rear. Moreover, the vacuuming of the first suction cup 21 (24) is controlled independently of the evacuation of the second suction cup 23 (26).

For ease of assembly and control, the two suction cups 21, 23 of the pair of straight suction cups are mounted on a straight support 31 for simultaneously moving the two suction cups 21, 23 and the two suction cups 24, 26 of the pair of suction cups. on the left support 32 for simultaneously moving the two suction cups 24, 26. In particular, in order to ensure the correction as described above, the simultaneous displacement of the two suction cups of each pair is carried out in a transverse direction (orthogonally to the direction of advancement A) and height.

Moreover, as can be seen from the Figs. 10 and 11 in order to follow the stroke of the cutout 10 in the direction of advance A while the correction is made by the suction cups 21, 23, 24, 26, the right support 31 (left 32) is mounted by a right bracket 33 ( left 34) to the rod 35 (36) of a straight linear motor 37 (left 38). Thus, on the Figs. 10A and 11A , there is shown a first position corresponding to the rest position, pending the arrival of a new cut and on the Figs. 10B and 11B a second position corresponding to the end position is shown when the blank has been folded, glued and possibly corrected.

We also see on Figs. 10 and 11 , the compression module 40 supplying air under partial vacuum to the right suction cups 21, 23 via a straight pipe 41 and supplying air under partial vacuum to the left suction cups 24, 26 via a left pipe 42.

To control the position of the right edge 13 and the left 14 after the folding of the right flap 17 and the left flap 18, it is preferably used optical detection means, not shown. For example, optical detection as described in the document is used. EP 0937573 .

These detection means measure the difference between the right edge 13 and the left edge 14 after the folding of the right flap 17 and the left flap 18 at several locations along the longitudinal direction. In this way, by comparison means, the comparison of each of these measured values with the reference gap, of predetermined value Ge, is carried out and it is determined whether a correction is necessary. In this case, it is calculated which retrofit must be made to return the cut to the acceptable range of deviation.

Several cases are possible such as a catch-up by acting on the only left pane 18, on the only right pane 17, both on the left pane 18 and on the right pane 17, and, for the pane (s), by the two suckers of the pair (right or left) concerned (gap only), by a single sucker of the pair (right or left) concerned (fishtailing only), by the two suckers and then by a single sucker of the pair (right or left) concerned (gap and fishtailing).

For example, the right support 31 and the left support 32 has a longitudinal stroke (along the axis XX 'of the folder gluer) of 200mm thanks to the linear motors 37 and 38. This longitudinal stroke can follow the cutout 10 during part of its advance while performing the correction during the advance along the advancement direction A. Also by way of example, the right support 31 and the left support 32 has a transverse travel (in the orthogonal direction to the XX 'axis of the folder gluer) between 10mm and 30mm. This transverse stroke is sufficient to make up for the anomalies encountered in most cases for a cut of maximum size, for example 1100mm by 1700mm. Pressure means for making a pressure contact between the right flap 17 and the left flap 18 in the covering portion.

We refer to Figs. 11A , 11B , 13 , 14 , 15 , 16A , 16B , 17A and 17B for the lower part of the correction device which completes the elements allowing the advance of the cut in the longitudinal direction by locking means of the central flap 19. The elements allowing the advance of the blank 10 are endless belts 60, visible three in number on the Figs. 16A , 16B , 17A and 17B and arranged parallel to each other under the suction cups 21, 23, 24, 26. These locking means are intended to retain the cutout 10 by its central flap 19 by preventing it from lifting, or to move laterally in particular. Without this retention of the cut by its central flap 19, the correction of the position of the right flap 17 and / or the left flap 18 could not be effected with efficiency and precision.

One embodiment of these locking means 70 of the central flap 19 uses (see Figs. 13 to 17 ), as a means of gripping the central flap 19, vacuum vacuum depression of the lower face of the central flap 19. Thus, the partial vacuum air allows to retain from below the central flap 19 which is retained by suction as long as the vacuum is maintained. More specifically, the blocking means 70 comprise at least one ramp 71 equipped with nozzles 72 oriented upwards and able to perform a vacuum. The outlet of these nozzles 72 opens on a support plate 75 on which the cutout 10 rests while being able to be driven by the belts 60. In the case shown, two ramps 71 are each arranged along the one and the Other external belts 60. For this purpose, the nozzles 72 act as suction cups by sucking down the underside of the central flap 19 when they are supplied with air under partial vacuum. For this purpose, a pressurization module 73 supplies partial ramp air 71 to the ramps 71 via the pipes 74.

The ramp 71 is mounted (see Figs. 13 to 17 ) on a linear motor 80 accompanying the cut 10 during its travel along the longitudinal direction of the folder-gluer machine. Thus, to achieve the gripping of the central flap 19 by its lower face, and lock in height but also in the transverse direction of the folder gluer, the vacuum of the ramps 71 is activated, whereby each nozzle 72 makes a grip a surface of the lower face of the central flap 19, thus making it possible to perform the correction of the right flap 17 and / or the left flap 18.

For ease and quick release, the linear motor 80 is placed along the transport means that advance the cut along the longitudinal direction of the folder-gluer. In the illustrated embodiment, as it appears on the Figs. 16A and 16B these transport means are endless belts 60. Advantageously, three endless belts 60 are arranged over the width of the module of the folder-gluer, and along and outside the two outer belts, is mounted a ramp 71 In a variant not shown, between each pair of belts 60 is mounted a ramp 71. In this way, the cuts 10 are driven by the belts 60 and are pressed downwards when the evacuation of the ramps 71 is activated.

It is understood that the linear motors 80 accompany the longitudinal stroke of the blank 10 in all cases, whether or not correction. Also, the linear motors 80 are retracted and returned to the initial position rapidly after the departure of the blank 10 from the correction device and before the arrival of the next blank 10 in the correction device.

Advantageously, the correction means (suction cups 21, 23, 24, 26) and the blocking means (ramps 71) are able to advance in the longitudinal direction (X-X ') of the folder-gluer machine at the same speed as the cut 10 during its longitudinal stroke. In practice, synchronization is effected between the motor controlling the longitudinal travel of the right support 31 and the left support 32 and the motor controlling the linear motors 80 supporting the suction nozzles 71.

Preferably, the bonding is carried out before folding the right flap 17 and the left flap 18. However, it is essential to avoid taking the glue in the covering portion between the right flap 17 and the left flap 18 before and during the control of the position (ie during steps d), e)), and during the eventual position correction (step f)). For this purpose, according to an advantageous arrangement, partially illustrated on the Fig. 13 it prevents the contact between the right flap and the left flap by an element 90 inserted between the right flap 17 and the left flap 18, and before step g) the element 90 is removed and a pressure contact is made between the adhesive, the right flap 17 and the left flap 18 in the covering portion, preferably until the glue.

In the machine, the correction device therefore preferably also comprises a member 90 adapted to be inserted between the right flap and the left flap before folding, and able to be removed after the correction. On the Fig. 13 , we see a partial representation of this element 90 which can be in the form of a rod fixed by its rear end from the top and allowing the passage of the cut just below the element 90. This is of an embodiment where the folding and the correction of the cut are carried out during the advance of the cutout 10. When the folding of the right flap 17 and the left flap 18, and during the control of position and of the possible correction, the right flap 17 and the left flap 18 are found above the rod, itself above the central flap 19. Then after correction, and when the pinch rollers act by pressing down, the more advanced position of the cutout 10 allows a release of the rod which is then output from the cut, whereby the contact between the right flap 17, the left flap 18 and the central flap 19 is provided to allow the taking of the glue.

In another embodiment, this element 90 is dispensed with: it then acts to correct the position of the right flap 18 and the left flap 17 relative to the central flap 19, in a sufficiently short time to allow this correction before taking glue.

The present invention is not limited to the embodiments described and illustrated. Many modifications can be made, without departing from the scope defined by the scope of the set of claims. A folder-gluer may also be a folding-gluing unit, mounted for example in an in-line machine, downstream of a flexo printing, and a rotary cut. The linear motors 37, 38 and 80 can be replaced by cylinders.

Claims (13)

1. Method for processing a blank (10) intended to form, after folding-gluing, a folded flattened box, the method comprising the following steps:

   a) supplying a substantially flat blank (10) comprising a right-hand edge (13), a left-hand edge (14), a front edge (11), a rear edge (12), a right-hand longitudinal crease (15) and a left-hand longitudinal crease (16), the right-hand longitudinal crease (15) and the left-hand longitudinal crease (16) delimiting, with the right-hand edge (13) and the left-hand edge (14) at least three flaps including a right-hand flap (17), a left-hand flap (18), and a central flap (19),

   b) applying glue in an area of the right-hand flap (17) adjacent to the right-hand edge (13) and/or in an area of the left-hand flap (18) adjacent to the left-hand edge (14), such that the glue is present in an overlapping portion between the right-hand flap (17) and the left-hand flap (18),

   c) folding the right-hand flap (17) 180° around the right-hand longitudinal crease (15) towards the central flap (19), and folding the left-hand flap (18) 180° around the left-hand longitudinal crease (16) towards the central flap (19),

   d) closing the folded right-hand flap (17) and the folded left-hand flap (18) which are located one above the other at least in the overlapping portion,

   e) checking by optical detection the position of the right-hand edge (13) and the left-hand edge (14) and comparing this effective position with a predetermined position so as to determine any positional deviation,

   f) when the positional deviation exceeds a permissible deviation value, carrying out the following sub-steps before the glue sets:

   f1) blocking the central flap (19) by its bottom surface using blocking means, operating with vacuum depression of the bottom surface, and comprising at least one ramp (71) equipped with nozzles (72) directed upwards and able to create a vacuum, and then

   f2) holding the top surface of the folded right-hand flap (17) and the folded left-hand flap (18) and

   f3) correcting the position of the left-hand flap (18) and/or the right-hand flap (17),

   g) applying pressure between the right-hand flap (17) and the left-hand flap (18) in the overlapping portion until the glue sets, and

   h) releasing the central flap (19), the right-hand flap (17) and the left-hand flap (18).
2. Method according to claim 1, wherein the holding of the top surface of the folded right-hand flap and the folded left-hand flap (18) during the step f2) is implemented respectively with at least one suction cup (21, 23, 24, 26) with vacuum, and that the positional correction of the left-hand flap (18) and/or the right-hand flap during step f3) is implemented by moving the suction cup (21, 23, 24, 26) with vacuum.
3. Method according to claim 2, wherein when the detected positional deviation is a distance between the right-hand edge and the left-hand edge not compliant with the permissible range, step f2) is implemented, for the right-hand flap and for the left-hand flap (18), with two suction cups (21, 23, 24, 26) offset in the longitudinal direction and set to vacuum during the holding, and step f3) is implemented with lateral movement of the two suction cups (21, 23, 24, 26) of the right-hand flap (17) and/or the left-hand flap (18), in order to modify the distance between the right-hand edge (13) and the left-hand edge (14) to bring it back in the permissible range.
4. Method according to claim 2, wherein when the detected positional deviation is a fault of parallelism between the right-hand edge and the left-hand edge, step f2) is implemented, for the right-hand flap and for the left-hand flap (18), with one suction cup (21, 23, 24, 26) set to vacuum during the holding, and step f3) is implemented with lateral movement of the suction cup (21, 23, 24, 26) of the right-hand flap and/or the left-hand flap (18), in order to modify the orientation the right-hand flap and/or the left-hand flap (18) to bring the right-hand edge (13) and the left-hand edge (14) substantially parallel one to the other.
5. Device for correcting the position of a blank (10) in a folder-gluer, for a substantially flat blank (10) comprising a right-hand edge, a left-hand edge, a front edge, a rear edge, a right-hand longitudinal crease (15) and a left-hand longitudinal crease (16) delimiting, the right-hand longitudinal crease (15) and the left-hand longitudinal crease (16) delimiting, with the right-hand edge and the left-hand edge at least three flaps including a right-hand flap (17), a left-hand flap (18), and a central flap (19), the device comprising:

   - means for folding the right-hand flap (17) and the left-hand flap (18),

   - checking means comprising optical detection of the relative position between the right-hand edge and the left-hand edge in transversal direction after folding the right-hand flap (17) and the left-hand flap (18),

   - means for blocking the central flap (19), comprising at least one ramp (71) equipped with nozzles (72) directed upwards, able to create a depression by vacuum of the bottom surface of the central flap of the blank (10),

   - means for gluing able to apply glue in an area of the right-hand flap (17) adjacent to the right-hand edge (13) and/or in an area of the left-hand flap (18) adjacent to the left-hand edge (14), such that the glue is present in an overlapping portion between the right-hand flap (17) and the left-hand flap (18),

   - means for correcting the position of the left-hand flap and/or the right-hand flap, and

   - means for pressurising (50) making it possible to create pressurised contact between the right-hand flap (17) and the left-hand flap (18) in the overlapping portion.
6. Device according to claim 5, wherein the means for correcting comprise at least one suction cup (21, 23, 24, 26) intended for holding the right-hand flap and at least one suction cup (21, 23, 24, 26) intended to hold the left-hand flap, the suction cups (21, 23, 24, 26) being directed downwards, vertically movable and in transversal direction and able to be subject to the vacuum.
7. Device according to claim 6, wherein the means for correcting comprise a pair of right-hand suction cups (21, 23) and a pair of left-hand suction cups (24, 26).
8. Device according to claim 7, wherein, for each pair of suction cups (21, 23; 24, 26), a first suction cup is located at the front and a second suction cup is located at the rear, and in that the vacuum of the first suction cup is controlled separately from the vacuum of the second suction cup.
9. Device according to claim 7 or 8, wherein the two suction cups (21, 23) of the pair of right-hand suction cups are mounted on a right-hand support (31) making it possible to move the two suction cups simultaneously and in that the two suction cups (24, 26) of the pair of left-hand suction cups are mounted on a left-hand support (32) making it possible to move the two suction cups simultaneously.
10. Device according to any one of claims 5 to 9, further comprising an element (90) able to be inserted between the right-hand flap (17) and the left-hand flap (18) before their folding, and able to be removed after the correction.
11. Device according to any one of claims 5 to 10, wherein the ramp (71) is mounted on a linear motor (80) accompanying the blank (10) during its travel and in that in case of correction, the vacuum is activated.
12. Device according to any one of claims 5 to 11, wherein the means for correcting and the means for blocking are further able to advance along a longitudinal direction at the same speed as the blank (10) during its longitudinal travel.
13. Folder-gluer machine equipped with a device for correcting according to any one of claims 5 to 12.

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