Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
  • B65D3/00—Rigid or semi-rigid containers having bodies or peripheral walls of curved or partially-curved cross-section made by winding or bending paper without folding along defined lines
  • B65D3/02—Rigid or semi-rigid containers having bodies or peripheral walls of curved or partially-curved cross-section made by winding or bending paper without folding along defined lines characterised by shape
  • B65D3/04—Rigid or semi-rigid containers having bodies or peripheral walls of curved or partially-curved cross-section made by winding or bending paper without folding along defined lines characterised by shape essentially cylindrical
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31F—MECHANICAL WORKING OR DEFORMATION OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31F1/00—Mechanical deformation without removing material, e.g. in combination with laminating
  • B31F1/20—Corrugating; Corrugating combined with laminating to other layers
  • B31F1/24—Making webs in which the channel of each corrugation is transverse to the web feed
  • B31F1/26—Making webs in which the channel of each corrugation is transverse to the web feed by interengaging toothed cylinders cylinder constructions
  • B31F1/28—Making webs in which the channel of each corrugation is transverse to the web feed by interengaging toothed cylinders cylinder constructions combined with uniting the corrugated webs to flat webs ; Making double-faced corrugated cardboard
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T156/00—Adhesive bonding and miscellaneous chemical manufacture
  • Y10T156/10—Methods of surface bonding and/or assembly therefor
  • Y10T156/1002—Methods of surface bonding and/or assembly therefor with permanent bending or reshaping or surface deformation of self sustaining lamina
  • Y10T156/1007—Running or continuous length work
  • Y10T156/1016—Transverse corrugating

Definitions

• the present invention relates to a method for manufacturing a rigid corrugated cardboard, a device for implementing the method and a corrugated cardboard obtained according to this method.
• Corrugated cardboard is a complex material composed of two to seven sheets of paper. The leaves are called covers when they are outside and medians when they are inside.
• grooves The grooved sheets which form the spacers and which are glued to the sheets mentioned above are called grooves.
• a type of corrugated cardboard can be likened to a flexible structure.
• This type of corrugated cardboard is single-sided corrugated cardboard called a single-sided sheet. This consists of a single-sided cover and a groove joined by dots of glue on the ridges of grooves in contact with the cover.
• This cardboard has the advantage of being able to be curved at will, in particular rolled up, without being folded. It is also stored in rolls and used in particular as wedging, support for various panels.
• a disadvantage of this cardboard is that it is not resistant since, by definition, it is not a profiled sandwich structure. It cannot therefore be directly used as part of a package and is limited in its applications.
• all the other corrugated cardboard can be assimilated to a rigid structure. Mention may be made, for example, of double-sided corrugated cardboard made up of a glued groove inserted between a single-sided cover and a double-sided cover, or double-sided corrugated cardboard made up of two glued flutes inserted between two single-sided covers and a cover double sided. From their manufacture, they are cut into plates and are therefore, by definition flat.
• corrugated cardboard They are resistant and can be used as part of a package, such as a box, the edges of which are the result of the fold lines of said cartons.
• a disadvantage of this type of corrugated cardboard is that before it can be used as part of a package it must undergo one or more creasing, operation which consists in partially crushing along a line the entire thickness of the corrugated cardboard facilitate subsequent folding of the flaps.
• the object of the present invention is then to overcome this drawback and therefore to propose a new method for manufacturing rigid corrugated cardboard which in particular makes it possible to obtain new curved shapes.
• the invention relates to a method of manufacturing a rigid corrugated cardboard comprising, beforehand, a step of producing at least one single-sided sheet of given width by gluing a groove to a single-sided cover.
• the following steps are carried out: a) the single-sided ply is bent to a desired shape, b) the edges of the groove of the curved single-sided ply are glued, c) at least one double-sided cover is glued same width as the single-sided ply on said single-sided ply so that it matches the curved shape of said ply.
• the term “given width” should be understood to mean the dimension of the sheet in the cross direction.
• curved shape should be understood to mean a shape which, seen in section perpendicular to the tops of the groove, defines a curved surface.
• Such a method is of very simple implementation since it is directly applicable from all known types of cover, for example made of kraft-liner paper, test-liner and, this, whatever the grammage envisaged . It is also applicable from all kinds of known grooves (semi-chemical, wood, standard, ordinary) and this regardless of the profile considered (micro, small, medium, large groove). Finally, the bonding can be carried out using conventional glues of the starch or vinyl type.
• this process makes it possible to offer packaging, in particular of small dimensions, which is both light and aesthetic.
• these packages have a very advantageous mechanical strength / weight ratio compared to existing ones which include compact cardboard and / or parts of rigid corrugated corrugated cardboard.
• step a) is carried out by closing the aforementioned single-face ply on itself.
• the single-sided ply has a closed and curved shape.
• a first variant of the invention consists, in a discontinuous manner, in cutting out a predetermined length of the single-face ply before bending it.
• a ratio of the length of the double-sided cover to the length of the single-sided cover is determined so as to best adjust the superposition of the two covers between they.
• an overlap may or may not be provided, the choice of such an overlap being guided by technical considerations (reinforcement of the curved assembly) and / or by aesthetic considerations.
• the double-sided cover is advantageously cut before or after being bonded to the curved single-side sheet.
• the whole of the rigid corrugated cardboard is cut continuously when bent.
• an assembly of the closed rigid corrugated cardboard according to the invention is advantageously carried out with a flat part, in particular a compact or corrugated cardboard, intended to serve as the bottom.
• the assembly is preferably carried out by mechanical means adaptable as a function of the size of the container and of the material of the attached flat part.
• the mechanical means can be crimping, gluing or stapling in the case of corrugated or compact cardboard, plastic or wooden bottoms.
• the invention also proposes a device for implementing the method.
• This device includes:
• the means for bending the single-sided sheet further comprise means for closing said sheet on itself.
• the device comprises a device for cutting out a predetermined length of the single-sided sheet and advantageously comprises a device for cutting out the bonded double-sided cover.
• the device comprises a device for cutting the curved rigid corrugated cardboard.
• the curving means comprise a mold, the surface of which is advantageously depressed.
• the single-sided sheet is easily applied against the mold which can be of relatively complex shape.
• the means for applying the double-sided covering on the single-sided ply may comprise at least one counter-mold of complementary shape in a bending zone.
• curvature zone it is necessary to understand here and in the rest of the text an zone where the concavity is turned towards the interior of the mold.
• the device may advantageously include an assembly device with a flat piece intended to serve as the bottom.
• the invention finally relates to a rigid corrugated cardboard obtained according to the preceding process.
• This cardboard is characterized by the fact that the radius of curvature of the minimum single-sided ply is approximately equal to H - 0, 5 p, where H and p represent respectively the height and the pitch of the groove.
• the invention uses as components all the usual known components and makes it possible to obtain new curved shapes of rigid corrugated cardboard. These have a structural rigidity quite comparable, if not greater, than that of known flat corrugated cardboard such as double-sided corrugated cardboard or double-sided cardboard.
• the corrugated cardboard according to the invention can be used in particular as a barrel, crate, box, envelope.
• FIG. 1 a perspective view of the lower part of a packaging box according to the invention
• FIG. 2a and 2b a general elevational view of a first device according to the invention and a half view -cut along line AA of this same device
• the box 1 has a side wall 2 with a rosette-shaped section 2.9 cm in height and below which is pasted a bottom 3 made of double-sided corrugated cardboard, the cover of which single-sided grammage equal to 1 40 g / m 2 is white top paper, type E flute and grammage equal to 1 40 g / m 2 is bleached kraft paper and double-sided cover grammage equal to 230 g / m 2 is printed white coated writing paper.
• the side wall 2 is produced from a single-sided corrugated cardboard 21 curved in the shape of a rosette and on the groove of which a double-sided cover 22 is glued.
• the covers and the groove of the side wall 2 have the same characteristics as those of the covers and the groove of the bottom 3.
• the rosette comprises twelve concavities turned alternately inwards and outwards from the box 1.
• box 1 One possible use of box 1 is the packaging of food products such as cheeses.
• This device 4 which allowed the manufacture of the side wall 2 of the box 1.
• This device 4 comprises a frame 5 on which is embedded a mold 6 in the form of a sleeve 1 m high with rosette section, the distance separating two opposite "external" concavities d being equal to 0.1 cm.
• This mold 6 is pierced with orifices 7 which open into a groove interior 8 which extends to the frame 5 and which is connected to a vacuum device not shown.
• the shaping of the single-sided sheet can thus be facilitated by this vacuum device.
• Each bracket 1 1 is fixed to the circular plate 9 by means of two screws 1 2 and has in its lower part an axis 1 3 around which a hollow cylinder 1 4 of length substantially equal to the height of the sleeve 6 can pivot d 'a horizontal position to a vertical position in the extension of the bracket 1 1.
• the device 4 also includes guide pads opposite the plate 9 (six in number in the case of FIGS. 2a and 2b) not shown, distributed uniformly over a circumference around the sleeve 6.
• These guide pads are intended to engage simultaneously in the extension of the stirrups 1 1 to a distance equal to 1.5 mm from the sleeve 6 when the cylinders 1 4 are in the horizontal position.
• a single-sided ply 21 of predetermined length exactly equal to the circumference of the sleeve 6 and of given width chosen substantially equal to the difference between the height of the sleeve 6 and the height of the stirrup 1 1, is positioned around this same sleeve 6.
• the device for putting the interior groove under vacuum 8 can be started, which can cause the vacuum to be put under vacuum. the outer surface of the sleeve 6 through the openings 7.
• the single-sided ply is, therefore, "pressed” against the sleeve 6 and therefore perfectly matches the shape of the latter.
• the guide pads are then released and a gluing device, not shown, applies a dry vinyl or starch-based glue to the periphery of the curved single-sided sheet.
• the vacuum device being always active.
• the guide pads are reengaged, which makes it possible to run along the sleeve 6 on which the single-sided ply 21 is bent, a double-sided cover 22 of dimensions identical to the latter.
• the cylinders 1 4 are lowered into a vertical position which, in contact with the double-sided cover 22, give it the corresponding internal concavities (C).
• the vacuum device is then deactivated, the cylinders 1 4 are kept in the vertical position, the time required for bonding.
• drying devices can be provided, for example by heating, along the sleeve 6.
• the cardboard complex is now dry, it suffices to cut by cutting strips the number of side walls 2 necessary for the manufacture of the box 1.
• This operation can be carried out for example using an arm equipped with a sharp blade and which “sweeps” the external surface at a speed such that the blade penetrates tangentially into each bending zone without risk of tearing the complex hardcover. It can also be performed using a laser. It is obvious that in this embodiment, the single-sided ply
• Figures 3a and 3b which must be connected by making the lines B -B and CC coincide, show a general elevation view of a second device according to the invention capable of being used continuously with part of a device for manufacture of double-sided corrugated cardboard.
• FIG. 3b For the sake of clarity and to facilitate understanding, the part of the device in FIG. 3b corresponding to the device according to the invention is shown on a larger scale than that of Figure 3a.
• This part comprises a coil 30 of a single-sided sheet of corrugated cardboard 21 and a reel 40 of double-sided cover 22.
• the single-sided sheet 21 and the double-sided cover 22 are of the same width.
• the essential difference which exists between this part and an upstream part of a known machine for manufacturing double-sided corrugated cardboard lies in the fact that the two above-mentioned coils 30, 40 are offset relative to each other by approximately half of the width transversely to the respective travel axes 31, 41 of the single-sided sheet and of the double-sided cover.
• the single-sided ply 21 is driven by a crenellated drum 32, controlled by a motor-variator and having the axial grooves in which fit the grooves of the corrugated cardboard.
• a counter-roller 33 keeps the sheet in contact with the crenellated cardboard.
• the sheet is then wound on a roller 34 arranged in such a way that the sheet only applies over a fraction of a turn of the drum.
• the double-sided ply for its part, is introduced between two drive rollers 42, 43 also controlled by a motor-variator.
• the bar feeder 35 comprises two fixed rollers 36, 37 around which the single-sided ply passes, forming a vertical loop, the end of which is wound on a freely suspended drum 38.
• the drum 38 moves vertically between a low position and a high position illustrated respectively in solid lines and in dashed lines in FIG. 3a.
• the single-sided ply 21 is then wound up on a servo drum whose role will be explained below, then it passes through a gluing device 50 controlled by a drive motor , not shown.
• This drum should be as light as possible so that its inertia does not generate excessive acceleration or deceleration effects. It takes glue by bubbling into a tank 51, the surplus being removed by a wringing roller 52 A pressing counter-roller 53 applies the single-sided ply 21 against the sizing drum 53. The grooves of the single ply face are thus glued.
• the servo drum 39 drives the motor of the sizing drum 53 so as to drive it at the same speed as that of travel of the single-sided sheet.
• the tablecloth would slide on the sizing drum and "wipe" the glue without impregnating it.
• Different known control systems 39 can be used.
• the servo-drum can be provided on its periphery with a notched disc of small width, which meshes in the grooves of the sheet and which is therefore driven at a speed perfectly synchronous with that of the sheet.
• This disc drives an optical encoder providing the servo frequency for controlling the drive motor of the sizing drum.
• FIG. 3b it can be seen that the single-sided sheet thus glued and the double-sided cover engage in an offset manner on the sleeve 6 with rosette section identical to that shown in FIGS. 2a and 2b.
• the axis of this sleeve 6 is inclined and forms an angle ⁇ with the axis of travel of the single-sided ply and of the double-sided cover and is in rotation at a speed corresponding to the linear drive speeds V, and V 2 mentioned above, using a variable speed motor not shown and located on the side of the reader.
• the angle ⁇ is in any case sufficiently small so as to allow the edge-to-edge positioning of the single-sided ply 21 at each rotation rotation carried out by the sleeve 6.
• the angle of inclination ⁇ of the sleeve 6 can obviously be different, knowing that it must remain within limits such that the extensibility limit of the single-sided ply 21 is not reached. In addition, it depends also the value of the transverse offset chosen between the two coils of components of the corrugated board.
• this angle of inclination which is therefore equal to the angle formed by the line of the tops of the groove and the axis of revolution of the sleeve 6, must be less than or equal to 45 °.
• This sleeve 6 is further provided throughout its range with a multitude of orifices not shown, identical to the orifices 1 1 in FIG. 2a.
• the orifices open into a groove of the cylindrical type, itself connected to a vacuum device of the vacuum pump type located on the side of the reader and not shown, which therefore "plates" the single-sided sheet 21 against the sleeve 6.
• the vacuum is in any case sufficiently low to allow the single-sided ply 21 to "run through” the sleeve 6 by forming a helix 60.
• This propeller 60 is covered with the double-sided cover 22 which is therefore pressed against it and adhered thereto, once the "offset" has been caught up by means not shown.
• These means are mechanical of the roller type whose shape is exactly complementary to that of the concavities of the sleeve 6 and / or of the pneumatic means of the pressurized enclosure type.
• Drying devices for example by electric heating, not shown are provided along the sleeve and therefore facilitate the drying of this cardboard complex thus formed.
• the complex passes through a rotary shearing device 70 of shape exactly complementary to the sleeve and consisting for example of a hard steel blade intended to shear the cardboard complex into several straight lateral bands 23 each having an equal width to the side wall 2 of the box 1 to be manufactured, such as that shown in FIG. 1.
• the axis of the shearing device must itself be exactly parallel to the axis of rotation of the sleeve 6 and have the same linear speed as the speed of movement of the single web. face.
• the cardboard lateral strips 23 thus cut out from the sleeve 6 and are stacked in boxes 80 with a movable bottom 81 located at the rear.
• the manufacture of a box 2 according to the invention ends with an operation of gluing a side strip on a bottom.
• the sleeves of the two devices according to the invention which have just been described can obviously take various forms such as a cylindrical sleeve or a sleeve with an ellipsoidal base, the length of the sleeve necessarily being greater than the width of the single-sided ply .
• the synchronization between the rotation speed and the respective linear speeds of travel of the single-sided sheet and of the double-sided cover is an important element which it is essential to control, otherwise the cardboard complex does not have the desired shape and, worse still, its manufacture is doomed to failure.
• the manufacturing devices described above make it possible to have access to packaging, in particular of small size, which is at the same time aesthetic, light and robust. This last characteristic is particularly highlighted using the comparative curves of FIG. 4. These are obtained from a crushing test which makes it possible to measure the compressive strength on edge, parallel to the edge of the groove and therefore allows to appreciate the dynamic compression.
• the tests were carried out using a device of the compressometer type from the company L&W which comprises two plates approaching at constant speed perpendicular to the groove.
• the resistance to crushing measurement then consists in recording the force measured in daN supplied by the plates as a function of the deformation of the test piece placed between these plates measured in millimeters.
• the curve in dotted lines in FIG. 4 relates to a wall 1 30 mm high with rectangular section, 1 80 mm long and 75 mm wide made from a double flat corrugated cardboard which has been grooved and then glued with vinyl glue, as a comparative example.
• This double-sided flat corrugated cardboard has a single-sided sheet whose single-sided cover of grammage equal to 1 50 g / m 2 in kraft paper is associated with a type C groove of grammage equal to 1 20 g / m 2 in VP paper and a double-sided cover of grammage equal to 200 g / m 2 in kraft paper.
• the curve in solid line in FIG. 4 relates to a cylinder of corrugated cardboard produced according to the invention of 1 30 mm in height and with a diameter equal to 1 65 mm, the bonding having also been carried out using a vinyl adhesive. .
• the characteristics of the components of this carton are strictly identical to those defined above
• the weight of the two boxes is substantially identical and is equal to 38.2 g.
• the elastic limits are substantially identical, the buckling rupture of the cardboard is absolutely avoided in the case of the specific structure according to the invention and there is therefore a certain "damping" effect in addition to a much better toughness. It can therefore be concluded that, for an identical weight, the resistance to longevity under stress provides a package with a given capacity with superior performance in the case where it is manufactured according to the invention.
• the packaging according to the invention will tend, in the event of too high a load, to gradually collapse instead of giving way suddenly, which is advantageous when the fragile and expensive contents are to be recovered. , for example, perishable goods, before crushing.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Making Paper Articles (AREA)
• Laminated Bodies (AREA)
• Machines For Manufacturing Corrugated Board In Mechanical Paper-Making Processes (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=9506621

Family Applications (1)

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Family Cites Families (9)

• 1997
  • 1997-05-06 FR FR9705558A patent/FR2763018B1/fr not_active Expired - Lifetime
• 1998
  • 1998-05-06 JP JP10547789A patent/JP2000513668A/ja active Pending
  • 1998-05-06 CZ CZ9931A patent/CZ3199A3/cs unknown
  • 1998-05-06 AU AU76600/98A patent/AU7660098A/en not_active Abandoned
  • 1998-05-06 EP EP98924384A patent/EP0930964A1/de not_active Withdrawn
  • 1998-05-06 CA CA002260260A patent/CA2260260A1/fr not_active Abandoned
  • 1998-05-06 US US09/147,458 patent/US20020000285A1/en not_active Abandoned
  • 1998-05-06 WO PCT/FR1998/000906 patent/WO1998050226A1/fr not_active Application Discontinuation
  • 1998-05-06 PL PL98330874A patent/PL330874A1/xx unknown
  • 1998-05-06 HU HU0002368A patent/HUP0002368A2/hu unknown
  • 1998-05-06 BR BR9804882-1A patent/BR9804882A/pt not_active Application Discontinuation

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