This invention relates generally to the field of packaging. More particularly, the invention relates to a line for manufacturing packagings in the form of folding boxes, from plate elements, for example, of corrugated cardboard.
In the packaging industry, cardboard cases, or boxes, are commonly made from plate elements in the form of flat or corrugated cardboard sheets. The plate elements are processed in a continuous stream in a packaging manufacturing line in which they are printed, cut and scored, folded and glued together to form the boxes.
With reference to
In the prior art packaging manufacturing line described above, a plate element shaping unit of the type described in WO 2013/029768 allows the achievement of a high manufacturing rate of up to 20,000 boxes/hour. This plate element shaping unit has four pairs of cylindrical shafts that are disposed transversely to the direction of transport of the plate element. The cylindrical shafts rotate at high speed and perform the various processing operations on the plate elements. The majority of the bends and cut-outs are carried out in the direction of transport of the plate elements in the unit. The shapes and dimensions of the slits are determined by cutting tools, mounted on cylindrical tool-carrying shafts, which ensure a rotary cutting. The movement of the plates is continuous between the cylindrical tool-carrying shafts and the cylindrical counter-tool-carrying shafts. The cylindrical counter-tool-carrying shafts are arranged in parallel and opposite to the cylindrical tool-carrying shafts, to engage with the latter. The rotary cutting tools comprise laterally spaced blades arranged to create the slits at and starting out from front and rear edges 14 and 15 of the plate element. In addition to the rotary cutting tools, the plate element shaping unit likewise comprises laterally spaced rotary scoring tools arranged to create the fold lines on the plate element.
In the plate element shaping unit, a lateral gluing tab 16 is likewise cut out of the plate element as an extension of the box sides 12. After folding, this tab is glued to the opposite box side to form the folding box 1c. For the execution of the lateral gluing tab, a specific tooling is provided in the plate element shaping unit, which tooling is arranged in such a way that two cuts are made transversely, or obliquely, in relation to the direction of transport of the plate element, as well as a first slitting starting from the rear edge and a second slitting starting from the front edge.
In the manufacture of packagings from plate elements, the arrangement of several layers in a single plate element is known, this in order to maximize the production of folding boxes in a packaging manufacturing line that has a set plate processing rate.
Document EP2228206 describes a packaging manufacturing line comprising a shaping unit having a plurality of rotating shafts, on which the shaping tools are arranged. Sheets of cardboard are shaped so as to produce two boxes from the same sheet. This is to say that the slitting and scoring operations that define two distinct boxes are carried out on the same sheet. A cutting unit provided with blades is arranged upstream of the folding-gluing module.
It is desirable to provide a solution which would allow an increase of the production of folding boxes in a packaging line of the type described above, with a shaping of the plate elements by means of pairs of rotating cylindrical shafts.
According to a first aspect, the invention relates to a packaging manufacturing line producing folding boxes from plate elements.
In accordance with the invention, the manufacturing line comprises:
In one variant, the shaping unit comprises two pairs of rotating cylindrical shafts which engage to provide central slits in each plate element aligned on a transverse center axis of the plate element, and two pairs of rotating cylindrical shafts engaging to respectively provide slits to the rear edge of a rear layer of the two juxtaposed layers of the plate element and slits to the front edge of a front layer of the two juxtaposed layers of the plate element.
In one variant, the shaping unit comprises a pair of rotating cylindrical shafts arranged to perform operations for the cutting of a box tab of a back layer of the two juxtaposed layers of the plate element and operations for the pre-scoring of fold lines in the two layers of the plate element.
In one variant, the shaping unit comprises a pair of rotating cylindrical shafts arranged to perform operations for cutting a box tab of a front layer of the two juxtaposed layers of the plate element, and operations for scoring of the fold lines in the two layers of the plate element, and a pair of rotating cylindrical shafts arranged to perform crushing operations in the two layers of the plate element.
In one variant, the shaping unit comprises first and second plate element processing units, associated in series, and having a same architecture with the pairs of rotating cylindrical shafts bearing a shaping tooling and through which the plate elements pass.
In one variant, the first and second plate element processing units each comprise four pairs of rotating cylindrical shafts aligned and arranged transversely to the direction of transport, the first and second plate element processing units being associated to form an alignment of eight pairs of rotating cylindrical shafts.
In one variant, in the direction of transport, the first plate element processing unit comprises second and fourth pairs of rotating cylindrical shafts engaging to make center slits in each plate element aligned on a transverse center axis of the plate element, and the second plate element processing unit comprises second and fourth pairs of rotating cylindrical shafts engaging to respectively provide rear edge slits of a rear layer of the two juxtaposed layers of the plate element and front edge slits of a front layer of the two juxtaposed layers of the plate element.
In one variant, in the direction of transport, the first plate element processing unit comprises a third pair of rotating cylindrical shafts arranged to perform operations for cutting of a box tab of a back layer of the two juxtaposed layers of the plate element and operations for pre-scoring of fold lines in the two layers of the plate element, and a first pair of rotating cylindrical shafts arranged to perform a conveyance of the plate element.
In one variant, in the direction of transport, the second plate element processing unit comprises a third pair of rotary cylindrical shafts arranged to perform cutting operations of a box tab of a front layer of the two juxtaposed layers of the plate element and operations for scoring of fold lines in the two layers of the plate element, and a first pair of rotating cylindrical shafts arranged to perform operations for crushing in the two layers of the plate element.
In one variant, the cutting unit is a rotary cutter with rotating cylindrical shafts.
In one variant, the unit for separating folding boxes comprises two separators for folding boxes arranged in series, one after the other.
In one variant, the line comprises a printing unit located, relative to the direction of transport, upstream of the plate element shaping unit.
In one variant, the line comprises a tying unit located, relative to the direction of transport, upstream of the unit for separating folding boxes, the tying unit having two individual tying machines for independently tying two assemblies of folding boxes stacked in the stack of folded assemblies.
Further advantages and features of this invention will become clearer from the following detailed description of a particular embodiment of the invention, with reference to the appended drawings, in which:
The longitudinal direction is defined with reference to the direction of travel or transport of the plate elements in the packaging manufacturing line, along their longitudinal centerline. The transverse direction is defined as the perpendicular direction in a plane that is horizontal to the direction of travel of the plate elements. The upstream and downstream directions are defined with reference to the direction of movement of the plate elements, following the longitudinal direction throughout the packaging manufacturing line, from the line entrance to the line exit. The proximal and distal edges of the plate element are defined in this non-limiting example with respect to the driver side and the side opposite to the driver side of the machine and the plate element shaping unit as the plate element travels forward.
With reference to
The plate elements in their different states of processing are globally referred to by the reference mark 4 in
The direction of transport of the plate elements 4 from upstream to downstream in the packaging manufacturing line 2 is indicated by the arrow FD in all of
As visible in
Thus, in the direction of transport FD of the sheets, the packaging manufacturing line 2 substantially comprises, in the example, an automatic plate element feeding station 20, a feeder 21, four flexographic printing units 22a to 22d, a shaping unit 33 with a plate element processing unit 23 and a cutting unit 24, a stripper-vibrator 25, a folder-gluer 26, a counter-ejector 27, a double tying machine 28, a unit for separating folding boxes 29 and a palletizer 30.
The plate element processing unit 23 in combination with the cutting unit 24 form a plate element shaping unit 33 (
Two conveyor tables 31 are arranged one after the other in this packaging manufacturing line 2, in order to achieve a 180 degree change of direction of the line to allow its implementation in a limited floor area. Other configurations are possible, for example without any table, so as to keep the tied stack 1e in the same rectilinear direction up to the unit for separating folding boxes 29, or with a single table for a 90 degree change in direction of the tied stack 1e.
The automatic plate element feeding station 20 has the function of feeding plate elements 4a to the packaging manufacturing line 2. The plate elements 4a are the blank plate elements to be processed by the line 2 to form the packagings. As is visible in
In station 20, the plate elements 4a are successively inserted, one by one, into the packaging manufacturing line 2 at a cadence corresponding to the machine step on which the various units of line 2 are synchronized.
After being inserted into the line 2, the plate element 4a is fed into the feeder 21. The feeder 21 performs an alignment operation and corrects, for example, a position of an edge of the plate element 4a to achieve the desired positioning for printing operations performed by the four printing units 22a to 22d.
The printing units 22a through 22d perform four-color flexographic printing on the plate element 4a, with the printing units 22a through 22d each printing a different color on the plate element 4a. The printing units 22a-22d output a printed plate element 4b, visible in
With reference to
The plate element processing unit 23 processes the printed plate element 4b and provides a cut plate element 4c. In the cut plate element 4c, slitting and scoring operations have been performed to form box sides 40 and box flaps 41 for each of the layers P1 and P2. Other cutting operations were also performed, such as an edge cut on a distal side edge 42 of the plate element and tab cutouts, on the proximal opposite side edge 43, to form a box tab 441 and 442 for each of the layers P1 and P2. The plate element processing unit 23 performs all of the processing operations on the printed plate element 4b in a single machine step, to obtain the cut plate element 4c.
The cutting unit 24 is typically a rotary cutter with rotating cylindrical shafts. The cutting unit 24 has the function of making the attachment points 45 between the layers P1 and P2 in the cut plate element 4c provided by the plate element processing unit 23, to obtain the cut plate element 4d.
In accordance with an embodiment example of the invention, the plate element processing unit 23 is formed by the association in series of two so-called slotter plate element processing units 23a and 23b, which preferably have the same general architecture. The first unit 23a is traversed before the second unit 23b by the plate element moving in the direction of transport FD.
The performance of the processing operations on the plate element is optimized, by distributing these processing operations judiciously between the two units 23a and 23b.
The plate element processing units 23a and 23b, are of the type with four pairs of rotating cylindrical shafts. The double plate element processing unit 23 formed by the combination of units 23a and 23b thus has eight pairs of rotating cylindrical shafts, 230a to 233a for unit 23a and 230b to 233b for unit 23b. The eight pairs of rotating cylindrical shafts, 230a to 233a and 230b to 233b, are spaced apart from each other at the same center distance AX, as shown in
The first plate element processing unit 23a makes central slits 4612 in the sheet. As shown in the cut plate element 4c, the central slits 4612 are aligned in a transverse central axis AL of the plate element and participate in the formation of the box sides 40 and box flaps 41 of the layers P1 and P2. The central slits 4612 are made here by the second and fourth pairs of rotating cylindrical shafts 231a and 233a which are equipped with suitable tools.
The first plate element processing unit 23a likewise performs first complementary processing operations which include the operations of cutting of the box tab 442 of the layer P2 and of pre-scoring operations 4712 for, in particular, the making of fold lines in the layers P1 and P2. These first complementary processing operations are performed by tools mounted, for example, on the third pair of rotating cylindrical shafts 232a of the first plate element processing unit 23a. The first pair of rotating cylindrical shafts 230a of the first plate element processing unit 23a is used here for conveyance of the sheet.
The second plate element processing unit 23b makes front edge slits 461 and rear edge slits 462. The slits 461 are made on a transverse front edge 48AV of the plate element and participate in the formation of the box sides 40 and the box flaps 41 of the layer P1. The slits 462 are formed on a transverse rear edge 48AR of the plate element and participate in the formation of the box sides 40 and the box flaps 41 of the layer P2. The front edge slits 461 and rear edge slits 462 are respectively made here by the fourth and second pairs of rotating cylindrical shafts 233b and 231b, which are provided with suitable tools.
The second plate element processing unit 23b also performs complementary second processing operations that include the operations of cutting of the body tab 441 of the layer P1 and final scoring operations 4712 for the performance of, in particular, the fold lines in the layers P1 and P2. These second complementary processing operations are performed by tools mounted, for example, on the third pair of rotating cylindrical shafts 232b of the second plate element processing unit 23b.
In the second plate element processing unit 23b, the first pair of rotating cylindrical shafts 230b performs a third complementary processing operation which corresponds to a crushing of the cardboard at the box tabs 441 and 442 on the proximal side edge 43, as well as a crushing of the cardboard at the opposite distal side edge 42. This crushing of the box tabs 441 and 442 and the opposite distal side edge 42 allows for the reduction of the thickness and is intended to avoid excess thickness in the folded and glued assembly 5 (
The performance by the double plate element processing unit 23 of the aforementioned processing operations results in the cut plate element 4c shown in
The cut plate element 4c is then fed into the cutting unit 24. Suitable tools are mounted in the rotating cylindrical shafts of the cutting unit 24 and make selective cuts in the plate element to obtain the attachment points 45. The cutting unit 24 outputs the cut plate element 4d comprising the layers P1 and P2 connected solely by the attachment points 45.
Referring once again, in particular, to
In the folder-gluer 26, the cut plate element 4d is folded and the box tabs 441 and 442 are glued to corresponding box sides to obtain the folded-glued assembly 5 formed by two folding boxes CA1 and CA2 connected by the attachment points 45, the two folding boxes CA1 and CA2 respectively corresponding to the layers P1 and P2.
The counter-ejector 27 recovers the folded assemblies 5 successively leaving the folder-gluer 26, counts them and forms a stack of folded assemblies 6 comprising a determined number of folded-glued assemblies 5 stacked on top of each other. The stack of folded assemblies 6 is then fed to the double tying machine 28.
The double tying machine 28 comprises two individual tying machines 28a and 28b entrusted with independently tying up the stacked folded boxes assembly CA1 and the stacked folded boxes assembly CA2. Two strapping bands, or ties 701 and 702 are thus placed on the stack of folded assemblies 6, the one 701 for the assembly of stacked folding boxes CA1 and the other 701 for the assembly of stacked folding boxes CA2. In this manner, a stack of tied up folded assemblies 7 is obtained, which is then fed to the unit for separating folding boxes 29.
The unit for separating folding boxes 29 is formed by the series combination of two separators 29a and 29b of folding boxes, also known as “breakers”. The two successive separators 29a and 29b of folding boxes are entrusted with separating the tied up stack of folded assemblies 7 into two batches of tied up and stacked folding boxes 81 and 82, as visible in
The breaking of the attachment points is achieved in the separators 29a and 29b, by an automatic process that involves, for example, while exercising pressure, maintaining the assembly of stacked folding boxes CA1 and the assembly of stacked folding boxes CA2 on two respective support panels and spreading, or inclination, between these support panels to cause the breakage.
The batches of folding boxes 81 and 82 are then taken over by the palletizer 30, which automatically manages groupings 9 (
The series combination of the two separators 29a and 29b, forming the unit for separating folding boxes 29, makes it possible to optimize and achieve the desired manufacturing rate for the manufacture of folding boxes, from cut plate elements, comprising two layers.
With the same machine step, this invention makes it possible to double the manufacturing rate of folding boxes when compared to the prior art packaging manufacturing line, described with reference to
The invention is not limited to the particular embodiment which has been described herein by way of example. The person skilled in the art, depending on the applications of the invention, may make various modifications and variants falling within the scope of protection of the invention.
Number | Date | Country | Kind |
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FR1902388 | Mar 2019 | FR | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2020/025113 | 3/6/2020 | WO | 00 |