ES1304309U9 - CARDBOARD BOX FROM A PLATE, PLATE FOR THE FORMATION OF A BOX, AND MOLDING ASSEMBLY, MOLD AND MACHINE FOR FORMING BOXES FROM PLATES - Google Patents

Description

DESCRIPTION

CARDBOARD BOX FROM A PLATE, PLATE FOR FORMING A BOX, AND MOLDING, MOLD AND FORMING MACHINE ASSEMBLY

BOXES FROM PLATES

TECHNIQUE SECTOR

The technical field of the present invention is the formation of containers of semi-rigid laminar material, with a polygonal cross section, for example, cardboard boxes, processed in a manner analogous to paper.

TECHNICAL PROBLEM TO SOLVE AND STATE OF THE ART

The technical problem of the present invention is the provision of a machine-automatable box, sustainable in environmental terms, lightweight, with minimal material development, and with improved mechanical resistance, via an effective link between larger and smaller side walls of the box. with extreme side roof fins of roof flaps, where boxes in a stacking situation are intended to be supported. Thus, the present invention addresses the achievement of low production costs, sustainable and high resistance.

The boxes with lateral roof fins and roof flaps are known in the sector as “platform” type/format boxes, and can be seen in Figs. 1 and 2 of document ES2691245A1 of the same owner and inventor of the present application, where vertical side fins 27 of the horizontal roof flaps 29 do not contact lateral ends of side walls 22.

For nearly 50 years to the present date, the previously mentioned “platform” cardboard boxes have been widely marketed, with success, where the lateral roof fins of the horizontal roof flaps do not contact, having a purposely pre-established clearance, with respect to lateral ends of long side walls, to avoid an overlap between these parts of the box during automatic assembly of the box, which drastically reduces the vertical compression resistance of the box.

However, an additional improvement of the vertical compression resistance in the corner areas of a platform-type box, at the junction of the lateral roof fins to join larger and smaller side walls, has been attempted for about 50 years. years repeatedly and without success, as evidenced by the following documents: US3783579A from the year 1974, ES235526U from the year 1978, ES282386U from the year 1984, ES1012930U from the year 1990, ES1024519U and ES1024598 from the year 1993, ES1035864U from the year 1996 , ES1046954U from the year 2000 , and ES1291059U from the year 2022.

Document US3783579A discloses the teaching of lateral roof fins with diagonal cuts coincident with complementary diagonal cuts of side walls to take advantage of the reinforced orientation of the cardboard grooves on the coincident diagonals. Said document US3783579A explicitly refers to the fact that the fins 224 and 225 have angular cuts 254 and 255 that exactly coincide with the cuts 265 and 257 in the fin 217, and that all edges, for example, edges 205 and 252, meet exactly in the finish, that is, these parts are flush with the assembled box, the same as in document ES1291059U.

The aforementioned document US3783579A discloses a method of forming the box by folding and joining parts of a flat plate, where packages of dairy products, for example, tetrabriks, are arranged on a bottom panel of the plate, prior to folding. The iron. In the method, the box is formed by pressing the side walls and side roof fins against the tetrabriks.

The boxes with roof flaps or "roofs" of documents ES235526U and ES282386U are designed for manual assembly and have a formation that is difficult to automate, mainly due to the complex insertion of tabs in slots to link the larger sides and smaller sides by snap-fitting. The tabs attached to the ear flaps have the disadvantage that they must have a height equal to the height of the box, so the cardboard development may be suitable for relatively tall boxes, but there is a waste of the cardboard development. not admissible when the boxes are of a lower height.

Similarly to document US3783579A, in the connection between first long side walls and second short side walls of the box of documents ES1024519U and ES1024598, the lower edge 4 of the ear flap 3 is not horizontal but inclined and determines an oblique, inclined or diagonally matching 6 with the edge of an inclined cut 5 made on the upper side of the larger side wall. These documents US3783579A, ES1024519U, ES1024598 provide the teaching that between the lug and the larger side wall, horizontal splicing lines are weak and that it is necessary to tilt the coincidence line between both to increase the resistance of the box to stacking.

On the other hand, in document ES1035864U, a lower edge 6" of the square flap 6 "ear" or "lug" is in contact, by means of a horizontal coincidence line, with the end edge 4' of the larger side wall 4. In the box, the height of the short wall 2 or end wall is identical to the sum of the height of the long side wall 4 plus the height of the ear 6 emerging from the roof flap 5.

In the box of document ES1046954U, trapezoidal flaps 8 are articulated at the ends of the roof flaps 6. The lower edge of the flaps 8 is longer than their upper edge, thus forming the trapezoidal flaps 8 a protrusion or tooth 9 of live artists.

It is described in the aforementioned document ES1046954U that the tooth 9 is housed and wedged in a recess 10 coinciding with the tooth 9 made in the upper edge of the long side wall 3. In the document ES1046954U, it is described that said wedge is when stacking containers one on top of the other, with the gravitational weight of the upper containers falling on the lower ones, when the extension flaps 8 are forced to fit over a watered end of the matching recess 10.

In view of the coining described in the aforementioned ES1046954U in the stacking, when the box is not stacked there is a clearance margin between the sharpened edge of the tooth 9 and the recess 10 shown in Figs. 1-3.

Following document ES1046954U, disadvantageously, the fixation of tooth 9 and socket 10 to the outside of the lateral extensions 5 of the short side walls 4, in combination with the clearance margin between tooth and socket, causes that tooth and socket do not They cannot be wedged in any way, offering non-existent vertical resistance both when the box is not stacked and when the box is stacked.

Disadvantageously, even if said alleged wedging occurs between the tooth and the recess 10 described in document ES1046954U, which is clearly non-existent, this wedging does not offer structural resistance to vertical loads due to the arrangement of the grooves of the corrugated sheet of the corrugated cardboard. parallel to the horizontal bottom panel, both on the long walls with grooves 10 and on the trapezoidal flaps with teeth 9. Thus, the vertical direction of the box stacking load is perpendicular to the direction of the grooves, where the corrugated cardboard It is very weak.

Document ES1046954U describes that the light box is generally made of corrugated cardboard, and in Figs. 1-3 shows that it is specifically made of single-wall corrugated cardboard with only three sheets: two smooth sheets, and one corrugated sheet sandwiched between the smooth sheets and joined to them. The Figs. 1-3 also disclose the direction of the corrugated sheet grooves on each part of the box. In the lateral extensions 5 and the short side walls 4, the grooves are perpendicular to the bottom panel 2, conferring high vertical resistance. In the long side walls 3 and in the trapezoidal flaps 8, where recesses 10 and teeth 9 are located, respectively, the grooves are parallel to the bottom panel 2, thus making the cardboard very weak when subjected to vertical resistance in the connection. between tooth 9 and pocket 10.

On the other hand, in documents ES1024519U, ES1035864U, ES1024498U, ES1037892U and ES1034949U, the parallel lines of each of the parts of the box (flaps, fins, panels) may represent shading, but they do not in any way represent the direction of the grooves of the corrugated sheets of cardboard, since the vertical grooves on both the long walls and the short side walls, characteristics that are not possible to obtain in a box from a single sheet of corrugated cardboard, a single sheet where The grooves of the corrugated sheet are parallel to each other over the entire surface of the plate, and that is why the grooves can be vertical on two facing side walls, but not on the four side walls of the rectangular box.

All of the aforementioned antecedents have the disadvantage that the lateral roof fin (also known as an ear flap or "ear flap") and a first side wall are attached and fixed by gluing to the lateral extensions of second side walls, and, therefore Therefore, although the ear and the first long wall have a coincident line or in horizontal or inclined contact, this is a weak union that does not obtain in any way a reinforcement that prevents improving the compression resistance and/or lateral resistance for vertical stacking between boxes.

Regarding methods and devices for forming boxes with horizontal roof flaps and lateral roof fins, within the framework of the present invention, documents ES2678670A1 and ES2691245A1 and ES2798155A1 can be cited, all of them from the same owner and inventor of the present application.

EXPLANATION OF THE INVENTION

According to a first aspect, to solve the drawbacks set out in the previous section, the present invention presents a cardboard box obtained by folding and gluing a flat die-cut sheet with weakened cutting lines and folding lines.

The box comprises a central bottom panel, delimited by two first mutually parallel and horizontal longitudinal fold lines, and by two first mutually parallel and horizontal transverse fold lines.

Thus, the background panel may be rectangular, octagonal or twelve-sided.

Throughout the present invention, the terms "longitudinal" and "transverse" generically designate two horizontal linear directions perpendicular to each other, and should be taken in a broad and non-limiting sense.

Furthermore, the box comprises two mutually facing first side panels, each connected by one of the first longitudinal fold lines to the bottom panel.

Also, the box comprises two mutually facing second side panels, each connected by one of the first transverse fold lines to the bottom panel.

Likewise, in the box, the first and second side panels are folded along the first fold lines and arranged around the bottom panel, forming four side walls facing each other in pairs, which define four corner areas of the box. The four side walls together with the bottom panel form a cavity to contain products.

Thus, the box may have four, eight or twelve side walls surrounding the central bottom panel.

Likewise, the box includes four side flaps. Each side flap is connected by a respective second vertical fold line to a respective lateral end of said second side panels, and each side flap is attached and glued to the first side panels, to link the first side panels to the second panels. sides through the four side flaps that emerge from the second side panels.

Also, the box includes two horizontal roof flaps. Each roof flap is connected by a respective second transverse fold line to a respective top of one of said second side panels. The horizontal roof flaps are configured to serve as a support for stacking several of these boxes, one on top of the other, forming vertical stacks of boxes.

Likewise, the box includes four lateral roof fins. Each side roof flap is connected by a respective third horizontal longitudinal fold line to a respective side end of the roof flaps and glued to one of the side flaps.

The box has a double-wall corrugated cardboard sheet structure, with three smooth sheets and two corrugated sheets, each corrugated sheet being joined to two of the smooth sheets to increase the resistance of the box.

This structure, being made of cardboard, that is, paper-based, provides an advantageous reduced biodegradation time compared to plastic or metallic laminate materials, while the double corrugated is a light as well as resistant solution, reducing weight in the transportation of the boxes, leading to a reduction in production costs of the box full of products.

Likewise, in the initially deployed state of the box of the present invention, corresponding to a flat plate, the sum of:

- a first length L1 coinciding with the transverse extension of the lateral roof fins, and

- a second length L2 coinciding with the transverse extension of the lateral ends of the first side panels,

is greater than a third length L3 coinciding with the longitudinal separation distance between the second transverse fold line and the first transverse fold line in the second side panels.

Likewise, in the box, due to said relationship between first, second and third lengths L1, L2, L3, the four lateral roof fins and the four lateral ends of the first side panels are preloaded under pressure, in vertical planes, by thrust. mutual in four lines of coincidence, and this preload necessarily occurs prior to a subsequent pressure connection of vertical glue cords of the lateral roof fins and the lateral ends of the first side panels on the side flaps.

Each match line includes a lower cut line of a lower end of one of the side roof fins and an upper cut line of a side end of one of the first side panels.

Tail beads may be continuous, discontinuous and/or a combination of these options.

Thus, the aforementioned characteristics are to increase the mechanical resistance of the box, for example, the vertical resistance to compression and/or the resistance to horizontal lateral loads, in the four corner areas, each corner area including the four lateral ends. of the side flaps and the first and second side panels, in addition to the side roof flaps and lateral end portions of the roof flaps.

The inequality of first, second and third lengths L1+L2 > L3 in the unfolded box, provides in the folded box a vertical pressure preload by thrust in the four lateral roof fins and the four lateral ends of the first side panels, providing advantageously four continuous vertical columns preloaded under pressure, joined by the preload under pressure at the four lines of coincidence.

The four continuous vertical columns of the box are contained in a vertical plane formed by the roof flaps and the lateral ends of the first side panels, and the thickness of each of these continuous vertical columns is advantageously associated with the thickness of the cardboard structure. double wall corrugated box.

Said preload necessarily occurs during a bending of the lateral roof fins and the first side panels, by the third longitudinal fold lines and by the first longitudinal fold lines, respectively, and said preload necessarily occurs before the subsequent joining with glue. the four lateral roof fins and the four lateral ends in pairs in each corner, so that said vertical preload is permanent once the box is assembled, whether the box is forming part of a vertical stack of boxes or if it is not in a position of stacking, thus achieving a real and effective increase in the compression resistance of the box, minimizing deformations of the box, and providing said double wall thickness in each corner area with an additional reinforced support surface against vertical loads.

That is, in the initially unfolded state of the corresponding box with a flat iron, the sum of:

- a first length L1 coinciding with the transverse extension of the lateral roof fins, associated with the height of the roof flaps pushed in preload once the box is obtained from the sheet; and of

- a second length L2 coinciding with the transverse extension of the lateral ends of the first side panels, associated with the height of the first side panels where the lower cut line at the lower ends of the lateral roof fins push in preload a once the iron is assembled in a box;

is greater than a third length L3 coinciding with the longitudinal separation distance between the second transverse fold line and the first transverse fold line in the second side panels, associated with the height of the box, associated in turn with the distance of separation between bottom panel and roof flaps once the box is assembled.

These first, second and third lengths of the unfolded state of the box are related (are associated) with their respective heights, but first, second and third lengths are not necessarily coincident with the respective heights. In fact, the sum of the first and second lengths are not coincident with the sum of their associated heights to preload the lateral roof fins and ends of the first side panels, thus increasing the resistance of the box.

Thus, in an illustrative, but not limiting, example of the box of the present invention:

- the first length L1 is equal to 73 mm;

- the second length L2 is equal to 128 mm;

- the third length L3 is equal to 195 mm;

- the height associated with the first length L1 is equal to 70 mm;

- the height associated with the second length L2 is equal to 125 mm; and

- the height of the box, associated with the third length L3, is equal to 195 mm.

In the example, you have to:

L1+L2 = 201mm;

L3 = 195mm;

From the illustrative example, it is verified that the relationship is fulfilled:

L1+L2 > L3.

In the example, the fact that L1+L2 is 6 mm larger than L3 provides such preload in the corner areas to increase the strength of the box.

Thanks to the relationship of measurements between first, second and third lengths of the initially deployed state of the box of the present invention, in combination with the articulation in respective upper and lower fold lines of the lateral roof fins and the lateral ends of the first side panels, the pressure preload is advantageously continuous/maintained during bending, and the magnitude of said pressure is advantageously increased in a smooth, progressive and controlled manner before the bending of lateral roof fins and the lateral ends of the first side panels and is increased until they reach a vertical position joined by pressure of vertical tail cords to the vertical side flaps.

Advantageously, the present invention provides an effective and real solution, unlike in the state of the art where the effect of increasing resistance is non-existent, to increase the vertical compression resistance in the four corner areas of the box. Thus, the present invention provides four vertical columns preloaded vertically under pressure, each associated with a thickness equal to a sheet of double-walled corrugated cardboard, and each of these columns is extended vertically continuously - thanks to the strong preload joint at the coincidence line - from the lateral ends of the roof flaps to the bottom panel of the box.

Advantageously, in the formed box, the vertical thrust of the pressure preload of the lateral roof fins, effectively and actually increases four additional upper support edges in stacking of improved resistance, and that is, thanks to the thrust of the preload under pressure, the first side panels are pushed down by the side roof fins and the side roof fins are pushed up by the first side panels, just before being joined by pressure of glue cords against the side flaps, providing thus a larger support surface, increasing the vertical compression resistance of the box.

Advantageously, the box may be assembled automatically, by machine.

Advantageously, in the box, the vertical compressive strength regardless of the orientation of the grooves of the corrugated sheets of the corrugated cardboard, that is, whether the grooves are horizontal or vertical in the lateral roof fins and lateral ends of the first panels sides.

Preferably, in the initially deployed state of the box, the sum of the first and second lengths is greater than the third length by a measurement between 0.2 and 2 centimeters, and more preferably between 0.4 and 1 centimeters.

Preferably, the box is obtained empty of the product to be contained, that is, the products are intended to be contained in it after the formation of the box, to advantageously avoid wastage of boxes, preventing the folding and pressing operations of some parts. of the box with others that damage extremely delicate products such as fruit and vegetable products, for example, fruits and/or vegetables, housed inside the box.

In the embodiments section, a series of optional examples are described for each inclined line of each coincidence line: a horizontal rectilinear line, a rectilinear inclined or diagonal line, an inclined line with a curved inclination, a broken inclined line, a plurality of inclined lines for each lower cut line and/or each upper cut line, and a combination of these, among other options.

Optional features of the first aspect of the present invention, and the subsequent second to sixth aspects of the invention, are described in the detailed embodiments section, where the respective advantages of each of these optional features are described.

According to a second aspect, to solve the drawbacks set out in the previous section, the present invention presents a flat plate, die-cut with weakened cutting lines and folding lines, for the formation of a box.

The plate comprises a central bottom panel, delimited by two first mutually parallel longitudinal fold lines and two first mutually parallel transverse fold lines.

Likewise, the plate comprises two first mutually facing side panels, each connected by one of the first longitudinal fold lines to the bottom panel.

Also, the plate comprises two second mutually facing side panels, each connected by one of the first transverse fold lines to the bottom panel.

Likewise, the plate includes four side flaps. Each side flap is connected by a respective second longitudinal fold line to a respective side end of said second side panels.

In addition, the plate includes two roof flaps. Each roof flap is connected by a respective second transverse fold line to a respective top of one of said second side panels.

Also, the sheet includes four lateral roof fins. Each lateral roof flap is connected by a respective third longitudinal fold line to a respective lateral end of the roof flaps.

Likewise, the plate has a double-wall corrugated cardboard sheet structure, with three smooth sheets and two corrugated sheets, each corrugated sheet being attached to two of the smooth sheets.

On the plate, the sum of:

- a first length L1 coinciding with the transverse extension of the lateral roof fins; and of

- a second length L2 coinciding with the transverse extension of the lateral ends of the first side panels;

is greater than a third length L3 coinciding with the longitudinal separation distance between the second transverse fold line and the first transverse fold line in the second side panels.

In the sheet, the first, second and third lengths L1, L2, L3 are jointly configured to allow, during a bending of the side roof fins and the first side panels of the sheet, to preload the side roof fins and the first side panels of the sheet. lateral ends of the first side panels by mutual push thereof, in respective four coincidence lines, each coincidence line including a lower cut line of a lower end of one of the lateral roof fins and an upper cut line of a lateral end of one of the first side panels, to increase the vertical compression resistance in the four corner areas of the sheet in the folded state, and to allow said preload to be maintained and increased during bending of the lateral roof fins and the first side panels towards vertical folded positions thereof.

The iron of the second aspect of the invention obtains the advantages described for the box of the first aspect of the invention.

Preferably, in the sheet, the corrugation grooves of the corrugated sheets are parallel to the second fold lines in the second side panels and the side flaps, to increase the vertical compressive strength in the folded state of the sheet, corresponding with a box.

According to a third aspect, to solve the drawbacks set out in the previous section, the present invention presents a method for forming boxes by folding and gluing flat sheets of die-cut cardboard with weakened cutting lines and folding lines.

For the formation of each of the boxes from a plate, the method includes the steps of:

- folding two mutually facing second side panels, each along a respective first horizontal transverse fold line connecting to a central bottom panel, to a folded position where the second side panels are vertical, perpendicular to the central bottom panel;

- fold four side flaps, along respective second horizontal folding lines connecting the side flaps to lateral ends of said second side panels, to a position where the side flaps are vertical, perpendicular to the two second side panels and the panel central background;

- after the folding step of the second side panels, fold two roof flaps to positions where they are horizontal, along second horizontal transverse folding lines connecting the roof flaps to upper parts of the second side panels, to provide a surface support in stacking boxes; and

- pre-fold two first mutually facing side panels, each along a respective first longitudinal fold line connecting to the central bottom panel, until a pre-folded position where the first side panels form first diagonal inclinations converging towards the panel background.

Likewise, the method also includes, in combination, the steps of:

- pre-fold four lateral roof flaps, each one by a respective third horizontal longitudinal fold line connecting to a respective lateral end of the roof flaps to a pre-folded position where lateral roof flaps form second converging diagonal slopes towards said horizontal roof flaps; and

- preloading under pressure, by mutual thrust on a respective line of coincidence of each side roof fin and each lateral end of the first side panels, each line of coincidence including a lower cut line of a lower end of one of the side fins roof and a top cut line of a side end of one of the first side panels.

Likewise, in the method, said preload stage is maintained and increased during a bending of the lateral roof fins and the first side panels from the diagonal pre-folded positions towards vertical folded positions, where the lateral roof fins and The first side panels are simultaneously positioned vertically and preloaded with said pressure.

Also, once the lateral roof fins and the first side panels are positioned in their vertical folded positions, it comprises the step of pressing and joining with vertical glue cords the lateral roof fins and the lateral ends of the first side panels on the vertical side flaps, the side roof fins and the lateral ends of the first side panels being simultaneously positioned vertically and preloaded under pressure, to increase the vertical compression resistance in four corner areas of the box.

The method of the third aspect of the invention obtains the advantages described for the box of the first aspect of the invention.

According to a fourth aspect, to solve the drawbacks set out in the previous section, the present invention presents a shaping assembly.

The molding assembly is intended to be installed in a mold of a machine for forming cardboard boxes from sheets, the mold comprising a plurality of benders arranged around a cavity for forming the boxes, which at least partially delimit a perimeter. of the cavity comprising four sides, two larger and two smaller, mutually facing each other in pairs, forming a molded tunnel with an essentially rectangular perimeter, configured to form boxes with a polygonal cross section, for example, rectangular or octagonal.

The forming assembly is configured to bend parts of each of the plates with respect to others, in cooperation with a core of the machine. Such a core is provided to engage vertically with the mold and the core is provided to be moved linearly in and out of the mold cavity to push at least a portion of a bottom panel of the plate into the cavity.

The molding assembly comprises two molding devices mutually facing each other and separated by a transverse separation distance, arranged around the cavity on mutually facing larger sides thereof.

Each shaping device comprises a first shaping section and a linear drive. Each first shaping section has a first vertical shaping surface movable guided by a respective linear drive associated with at least one first horizontal guide along a transverse linear direction, between a first receiving position and an active position.

In the forming assembly, each shaping device further comprises a second shaping section. Each second shaping section has a second vertical shaping surface connected to at least one second horizontal guide. Each second molding section has connected a positioning recuperator element of the second molding section in a second receiving position.

In each shaping assembly of the forming device, the second shaping section is movable by the linear drive along the first Y transverse direction, from the second receiving position to the active position of the first shaping section.

In the shaping assembly, with the first and second shaping sections in the receiving position, the first shaping surfaces are spaced apart from each other by a first separation distance, and the second shaping surfaces are spaced from each other by a second separation distance.

In the first and second receiving positions, the first and second separation distances are of different measurements, with the first and second shaping sections being jointly configured to receive four lateral roof fins pre-folded diagonally downward by third upper horizontal longitudinal fold lines. and to receive four lateral ends of first side panels pre-folded diagonally upward by first lower longitudinal fold lines, wherein the third longitudinal fold lines connect the four lateral roof flaps to lateral ends of two horizontal roof flaps, to their connected to upper parts of two mutually facing second vertical side panels, in turn connected by first transverse fold lines to a central bottom panel, and wherein the first longitudinal fold lines connect the first mutually facing side panels to the back panel. background.

In each shaping device (40) of the shaping assembly, the first and second shaping sections are jointly joined from intermediate positions thereof to the active position common to both, during a path of movements of the first and second shaping sections according to the first transverse Y direction.

From the intermediate positions of the first and second molding sections to their active position, the first separation distance between first molding surfaces is equal to the separation distance between second molding surfaces. In these positions, the first and second shaping sections are configured to bend the side roof fins and the first side panels, and to, during said bending, continuously pressure preload by mutual thrust, at a respective line of coincidence of each side fin. of roof and each lateral end of the first side panels. The shaping assembly is configured to preload each mating line disposed between each lower cut line at the lower ends of the side roof fins and each upper cut line at the side ends of the first side panels.

In the active position, the first separation distance between first shaping surfaces is equal to the second separation distance between second shaping surfaces.

In the active position, the first separation distance is equal to the second separation distance, and the first and second shaping sections are jointly configured to simultaneously press together vertical glue beads, the side roof fins and the first side panels. , against four vertical side flaps connected, by second vertical fold lines, to respective lateral ends of the second side panels of the box.

Advantageously, the forming assembly enables the automated production on a machine of a box with upper lateral roof fins pre-folded downwards by upper longitudinal fold lines and first side panels pre-folded upwards by lower longitudinal fold lines, to be joined. by pressure and glue previously applied on the plate, on vertical side flaps, fins and ends of first side panels, which are preloaded under pressure by mutual push, prior to their subsequent union against the vertical side flaps.

Thus, advantageously, the present forming assembly manages to assemble in an automated manner, considerably reducing costs and production times of these boxes, including a considerable reduction in waste of these boxes.

Advantageously, the different measurements of the first and second reception position separation distances of the first and second molding sections allow a bending order to be predefined, and enable a controlled initial contact of the lateral roof fins and lateral ends of the first to be pre-established. side panels on the matching lines, avoiding unwanted overlaps of fins and first side panels that dramatically reduce the compressive strength of the box.

Advantageously, the integral union of the first and second molding sections, which causes the first and second molding sections to advance positionally in unison, simultaneously, towards the center of the cavity from the sides, maintaining equal separation distances between first and second molding sections, contributing to the progressive, smooth and controlled increasing pressure with the bending of the lateral roof fins and the first side panels, avoiding unwanted overlaps between the lower ends of the roof fins and the upper portions of the lateral ends of the first panels sides.

These unwanted overlaps, advantageously avoided with the molding assembly, would cause an unwanted decrease in the vertical compression resistance of the box since they prevent the surfaces of the fins and first side panels from being completely attached, coplanar, and joined by pressure and glue on the vertical side flaps.

Optionally, the molding assembly of the fourth aspect of the invention may be used to obtain the box of the first aspect of the invention.

According to a fifth aspect, to solve the drawbacks set out in the previous section, the present invention presents a mold for a box forming machine from flat cardboard sheets.

The mold comprises a plurality of benders arranged around a cavity for forming the boxes, at least partially delimiting a perimeter of four sides of the cavity, configured to bend some parts of the plates with respect to others in cooperation with a male of the movable machine in and out of said cavity.

The plurality of benders comprises two first bending devices mutually facing each other a first distance greater than the width of the box, configured to pre-fold two first side panels mutually facing each other, each by a respective first longitudinal fold line connecting to the central bottom panel , to a pre-folded position where the second side panels form first diagonal inclinations converging towards the bottom panel.

Also, the plurality of benders comprises two mutually facing second bending devices, configured to fold two mutually facing second side panels, each along a respective first horizontal transverse fold line connecting to a central bottom panel, to a folded position where the second side panels are vertical.

Likewise, the plurality of benders comprises four third bending devices located in corners of the mold, sandwiched between a first and second bending device, configured to fold four side flaps, by respective second longitudinal and horizontal folding lines connecting the side flaps. to lateral ends of said second side panels, to a position where the side flaps are vertical.

Likewise, the plurality of benders comprises four fourth bending devices located in the corners of the mold, sandwiched between a first and second bending device, configured to pre-bend lateral roof fins, each along a respective third horizontal longitudinal folding line of connection to a respective lateral end of the roof flaps, to a pre-folded position where the second side panels form second diagonal inclinations converging towards said horizontal roof flaps.

Furthermore, the plurality of folders comprises two mutually facing fifth folding devices, configured to fold two roof flaps to positions where they are horizontal, by second horizontal transverse folding lines connecting the roof flaps to upper parts of the second side panels.

Also, the mold comprises the molding assembly of the four aspect of the invention.

The mold of the fifth aspect of the invention obtains the advantages described for the forming assembly of the fourth aspect of the invention.

Optionally, the mold of the fifth aspect of the invention may implement the method of the third aspect of the invention.

According to a sixth aspect, to solve the drawbacks set out in the previous section, the present invention presents a machine for forming boxes from flat cardboard sheets.

The machine comprises a plate conveyor that includes a pusher movable between two lateral guides. The conveyor is configured to linearly transport plates, one by one, from an origin position associated with a warehouse of flat plates, to a position where the plate is sandwiched between a core and a mold facing each other vertically.

Furthermore, the machine comprises a gluing device that includes a plurality of glue injectors configured to apply beads of glue on the plates during their transportation along the conveyor.

Likewise, the machine comprises said core, linearly movable in and out of a mold cavity, the core having a pushing surface configured to push the plate into the cavity.

Likewise, the machine comprises the mold of the fifth aspect of the invention.

The machine obtains the advantages described for the mold of the fifth aspect of the invention, which includes the forming assembly of the fourth aspect of the invention.

Optionally, the machine of the sixth aspect of the invention may implement the method of the third aspect of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other advantages and characteristics will be more fully understood from the following detailed lists of embodiment examples with reference to the accompanying drawings, which are to be taken by way of illustration and not limitation, in which:

Fig. 1 is a plan view of a first embodiment of the iron of the second aspect of the invention, and wherein Fig. 1 shows beads of glue applied to the iron to join some parts of the iron with others. ;

Fig. 2 is a profile view of the iron of Fig. 1;

Fig. 3 is an enlarged view of detail IV of Fig. 2, where the double-wall corrugated cardboard structure is shown;

Fig. 4 is a top perspective view of the first box embodiment of the first aspect of the invention obtained from the plate of Fig. 1, where the direction of the grooves of the corrugated cardboard in the parts of the box, and where in only one of the four corner areas of the box the glue cords connecting some parts of the box to others have been artificially transparent;

Figs. 5, 6 and 7 are respective top perspective views of a second, third and fourth box embodiments of the first aspect of the invention, respectively, obtained from plates similar to that shown in Fig. 1;

Fig. 8 is a top perspective view of a fifth box relationship of the first aspect of the invention, obtained from plates similar to that shown in Fig. 9;

Fig. 9 is a plan view of a second embodiment of the iron of the second aspect of the invention, showing beads of glue applied to the iron to join parts of the iron with others;

Fig. 10 is a top perspective view of a sixth box embodiment of the first aspect of the invention obtained from the plate of Fig. 9, where the direction of the grooves of the corrugated cardboard in the parts of the box, and where in only one of the four corner areas of the box the glue cords connecting some parts of the box to others have been artificially transparent;

Figs. 11, 12, 13 and 14 are respective top perspective views of a seventh, eighth, ninth and tenth box embodiments of the first aspect of the invention, respectively, obtained from plates similar to that shown in Fig. 9;

Figs. 15 to 20 show a sequence of forming the plate of Fig. 1 in a box, according to the method of forming boxes from plates of the second aspect of the invention, where:

Fig. 15 is a top perspective view of a machine for forming boxes from flat cardboard sheets of the sixth aspect of the invention, where the molding assembly of the fourth aspect of the invention and the fifth aspect mold are installed. of the invention, and which has the flat plate of Fig. 1 arranged between the core and the mold supported by lateral guides of a plate conveyor prior to its formation in a box;

Fig. 16 is a top perspective view of the machine of Fig. 15 at a later time than shown in Fig. 15, where the box has been pushed into the mold and formed by the mold in cooperation with the male;

Fig. 17 is a schematic cross-sectional side view of the mold of Fig. 16, where some of the mold elements have been omitted to more clearly show the molding assembly of the fourth aspect of the invention installed in the mold, and wherein the first and second shaping sections are in the first and second retracted positions;

Fig. 18 is a schematic cross-sectional side view of the mold of Fig. 17, now at a later moment of formation of the box by the molding assembly where the first and second molding sections are in respective intermediate positions, where they initiate preloading by pushing the lateral roof fins and lateral ends of the first side panels;

Fig. 19 is a schematic cross-sectional side view of the mold of Fig. 18, now at a later moment of formation of the box by the molding assembly, where the first and second molding sections are in respective closer intermediate positions. to the active position of Fig. 20, where the thrust preload of lateral roof fins and lateral ends of first side panels is greater in magnitude than that of Fig. 18;

Fig. 20 is a schematic cross-sectional side view of the mold of Fig. 19, now at a later moment of forming the box by the molding assembly, where the first and second molding sections are in the active position to join by pressure of glue cords some parts of the box previously preloaded by pushing with others simultaneously;

Fig. 21 is a rear perspective view of a shaping device of the shaping assembly of Figs. 15-20 installed on a mold base support;

Fig. 22 is a rear perspective view of the shaping device of Fig. 21;

Fig. 23 is a rear perspective view of a first part of the shaping device of Fig. 22 including the first shaping section;

Fig. 24 is a rear perspective view of a second part of the shaping device of Fig. 22 including the second shaping section;

Fig. 25 is a schematic cross-sectional side view of the mold of Fig. 16, according to a second embodiment, where some of the mold elements have been omitted to show more clearly a second embodiment of the molding assembly of the fourth aspect of the invention installed in the mold, and wherein the first and second molding sections are in the first and second retracted positions; and

Fig. 26 is a schematic cross-sectional side view of the mold of Fig. 16, according to a third embodiment, where some of the mold elements have been omitted to show more clearly a third embodiment of the molding assembly of the fourth aspect of the invention installed in the mold, and wherein the first and second molding sections are in the first and second retracted positions.

DETAILED EXPOSITION OF IMPLEMENTATION MODES / EXAMPLES

In Figs. 4-8, 10-14 and 20, reference 80 generically designates a cardboard box (80). The boxes (80) of said figures are obtained by folding and gluing a flat plate (60), punched with cutting lines and weakened folding lines as shown in Figs. 1-3, 9 and 15.

Commonly to all embodiments, Figs. 4-8, 10-14 and 20 show that the box (80) comprises a central bottom panel (61), delimited by two first longitudinal fold lines (64) mutually parallel and horizontal, and by two first transverse fold lines (65) mutually parallel and horizontal.

Throughout the present invention, the terms "longitudinal" and "transverse" generically designate two horizontal linear directions perpendicular to each other, and should be taken in a broad and non-limiting sense.

In the figures, the first direction (X) is a horizontal longitudinal direction and the second direction (Y) is a horizontal transverse direction perpendicular to the first direction (X).

Continuing in all box embodiments (80), the box (80) comprises two mutually facing first side panels (62), each connected by one of the first longitudinal fold lines (64) to the bottom panel (61).

Continuing in all box embodiments (80), the box (80) comprises two mutually facing second side panels (63), each connected by one of the first transverse fold lines (65) to the bottom panel (61).

In the boxes (80) of Figs. 4-8, 10-14 and 20, the first and second side panels (62, 63) are folded along the first fold lines (64, 65) perpendicular to the bottom panel (61), and arranged around the bottom panel (61), forming four side walls facing each other in pairs, which define four corner areas of the box (80). The four side walls together with the bottom panel (61) form a cavity to contain products.

In Figs. 4-8, 10-14 and 20, the box (80) further comprises four side flaps (66). Each side flap (66) is connected by a respective second vertical fold line (67) to a respective lateral end of said second side panels (63), and each side flap (66) is attached and glued (CC) to the first side panels (62), to link the first side panels (62) with the second side panels (63) through the four side flaps (66) that emerge from the second side panels (63).

Optionally, Figs. 4-8, 10-14 and 20 show that the first side panels (62) are larger side panels and the second side panels (63) are smaller side panels, smaller in size than the larger ones.

In Figs. 4-8, 10-14 and 20, the box (80) also comprises two horizontal roof flaps (68). Each roof flap (68) is connected by a respective second transverse fold line (69) to a respective top of one of said second side panels (63).

Continuing in these figures, the roof flaps (68) partially obstruct, in the upper part of the second side panels (63), the upper open mouth of the cavity of the box (80) formed by first and second side walls (62, 63) and background panel (61).

Likewise, the horizontal roof flaps (68) serve as support for stacking several of these boxes (80), one on top of the other, forming vertical stacks of boxes (80).

Commonly to all embodiments, Figs. 4-8, 10-14 and 20 show that the box (80) comprises four lateral roof fins (70). Each side roof flap (70) is connected by a respective third horizontal longitudinal fold line (71) to a respective side end of the roof flaps (68) and attached with glue (CC) to one of the side flaps (66). .

Commonly to all embodiments, Figs. 4-8, 10-14 and 20 show that the box (80) has a double-walled corrugated cardboard sheet structure, with three smooth sheets (78) and two corrugated sheets (79), each sheet being corrugated (79). joined to two of the smooth sheets (78) to increase the resistance of the box (80), as detailed in Figs. 3 and 17-20.

Commonly to all embodiments, in the initially deployed state of the box (80), corresponding to the flat plate (60) shown in Figs. 1-2, 9 and 15, the sum of:

- a first length L1 coinciding with the transverse extension of the lateral roof fins (70), and

- a second length L2 coinciding with the transverse extension of the lateral ends of the first side panels (62),

is greater than a third length L3 coinciding with the longitudinal separation distance between the second transverse fold line (69) and the first transverse fold line (65) in the second side panels (63).

In an illustrative, but not limiting, example, in the box (80) of Figs. 4-8, 10-14 and 20:

- the first length L1 is equal to 73 mm;

- the second length L2 is equal to 128 mm;

- the third length L3 is equal to 195 mm;

- the height associated with the first length L1 is equal to 70 mm;

- the height associated with the second length L2 is equal to 125 mm; and

- the height of the box, associated with the third length L3, is equal to 195 mm.

In the example, you have to:

L1+L2 = 201mm;

L3 = 195mm;

From the illustrative example, it is verified that:

L1+L2 > L3.

Thus, in the previous example, when going from the initially deployed state of the box (80) (in the form of a flat sheet (60)) to the folded state of the formed box (80), the shortening of 6 mm of L1+L2 provides a preload in the corner areas of the box (80) formed to increase the strength of the box.

Continuing in all embodiments, in box (80) of Figs. 4-8, 10-14 and 20, the four lateral roof fins (70) and the four lateral ends of the first side panels (62) are preloaded to vertical pressure (P1', P2'), according to the vertical direction ( Z), as shown in Fig.20.

Said preload in the box (80) is due to mutual thrust between four lateral roof fins (70) and the four lateral ends of the first side panels (62) in four coincidence lines (72), as shown in Figs. 19 and 20.

In Fig. 18, during the bending of the lateral roof fins (70) and first side panels (62), by respective longitudinal and horizontal folding lines (71, 64), the lower and upper ends of these parts of the roof contact. the box (80) being formed.

Subsequently, in Fig. 19, P1 generically designates a preload by thrust pressure of the lateral roof fin (70) on the end of the first side panel (62), while P2 generically designates a preload by thrust pressure of the lateral roof fin (70) on the end of the first side panel (62), during the folding of the lateral roof fins (70) and first side panels (62), along the third longitudinal fold lines (71) and by the first longitudinal fold lines (64), respectively.

In Fig. 19, the thrust pressure between side roof fins (70) and first side panels (62) is continuous and increases progressively, for example, from a lower first thrust pressure (P1, P2) of Fig. 19 until a subsequent increased second thrust pressure (P1', P2') of Fig. 20.

In Fig. 20, the vertical side roof fins (70) are preloaded by the second vertical thrust pressure (P2'), aligned with the vertical direction (Z), exerted by the ends of the first side panels (62). . Likewise, in Fig. 20, the first side panels (62) are preloaded by the second vertical thrust pressure (P1'), aligned with the vertical direction (Z), exerted by the vertical side roof fins (70).

In Figs. 19 and 20, said preload by thrust pressure between parts of the box (80) is necessarily prior to a subsequent pressure union of vertical glue cords (CC) of the lateral roof fins (70) and the lateral ends of the first side panels (62) on the side flaps (66).

Thus, in Figs. 4-8, and 10-14 and 20, once the box (80) is assembled, said push pressure preload on the four lateral roof fins (70) and the four lateral ends of the first side panels (62) , provides four continuous vertical preloaded pressure columns, joined by the pressure preload at the four match lines (72).

Said preloaded parts of the box are represented in Fig. 20 with the thrust pressures (P1', P2') vertical.

Following the boxes (80) of Figs. 4-8, and 10-14 and 20, each match line (72) includes a lower cut line (70i) of a lower end of one of the side roof fins (70) and an upper cut line (62s ) of a lateral end of one of the first side panels (62).

In Figs. 17-20, said preload occurs during a bending of the lateral roof fins (70) and the first side panels (62), shown in the sequence of Figs. 18, 19 and 29, by the third longitudinal fold lines (71) and by the first longitudinal fold lines (64), respectively.

In Figs. 17-20, said preload occurs before the subsequent union with vertical glue cords (CC), shown in Fig. 4-8, 10-14 and 20, of the four lateral roof fins (70) and the four ends side panels in pairs at each corner of the first side panels (62), so that said vertical preload is permanent once the box (80) is assembled, whether the box (80) is forming part of a vertical stack of boxes (80). ) as if it were not in a stacking situation, thus achieving a real and effective increase in the compressive strength of the box (80), said double wall thickness providing in each corner area of the box (80) an additional surface of reinforced support against vertical loads.

In the sequence of Figs. 18-20, with the continued preload in lateral roof fins (70) and lateral ends of first side panels (62), the upper ends of the lateral roof fins (70) connecting to the longitudinal fold lines (71) They are slightly displaced upward by the lateral ends of the first side panels (62), until the upper ends of the side roof fins (70) are vertically level or slightly above the horizontal roof flaps (68) in the box (80). ) obtained from Fig. 20.

In the sequence of Figs. 18-20, with continued preload on roof side fins (70) and side ends of first side panels (62), the lower ends of the side ends of the first side panels (62) are moved downward until they are vertically level or slightly below the lower face of the bottom panel (61) in the box (80) obtained from Fig. 20.

In Fig. 19, the first and second lengths (L1, L2) of Fig. 18 are optionally reduced via a progressive reduction of the lower and upper roundnesses of the horizontal longitudinal fold lines (71,64).

Advantageously, thanks to the previously explained optional reduction of the roundness of the horizontal longitudinal folding lines (71,64), the horizontal support surface is increased, increasing the vertical compression resistance and reducing the deformation of the roof flaps (68) and of the bottom panel (61) when the box is in a stacking situation, forming part of a vertical stack of boxes (80) full of product, arranged one on top of the other.

In the box options (80) shown in Figs. 4-6, each lower cut line (70i) and each upper cut line (62s) is a horizontal rectilinear line, each match line (72) being a horizontal rectilinear line.

Advantageously, in this option of horizontal coincidence line (72), the box (80) has a minimum development of sheet cardboard regardless of the height of the box (80), that is, regardless of the vertical distance between the bottom panel. (61) horizontal and roof flaps (68) horizontal, while the box (80) obtains improved compression resistance due to the aforementioned preload.

According to some preferable options of Figs. 7-8, 10-14, in the box (80), each match line (72) comprises an inclined (diagonal) line, each lower cutting line (70i) comprising a first inclined line, and each cutting line comprising upper (62s) a second inclined line complementary to the first inclined line.

In these preferable options, each first and second line jointly form a tooth (70e) with a crest and a notch (62e) with a valley, mutually complementary, to engage/interlock the ends formed by the first inclined line with the ends formed by the second inclined line during mutual pushing between each lower cut line (70i) and upper cut line (62s). This fitting is necessarily prior to the joining with glue cords (CC) of the lateral roof fins (70) and the lateral ends of the first side panels (62) on the side flaps (66). This interlocking necessarily occurs during the folding of the lateral roof fins (70) and the first side panels (62).

Advantageously, the inclined / diagonal line of each match line (72) provides in the teeth (70e) and notches (62e) an improved compression and/or lateral resistance since due to said inclination of the match lines (72) in a direction other than a direction parallel to the grooves (77) of the corrugated cardboard sheets, at the line of coincidence the side roof fins (70) and first side panels (62) are pushed together through a sheet of corrugated cardboard cut with inclined cutting lines, where the smooth and corrugated sheets (78, 79) of the cardboard structure offer greater resistance.

Advantageously, teeth (70e) and notches (62e) are self-guided longitudinally, according to the direction (X) of the figures, in their mutual coupling in the corner areas of the box (80), avoiding unwanted overlaps of lateral roof fins ( 70) and lateral ends first side panels (62) to maintain high resistance of the box (80).

In the box (80) of Fig. 7, each match line (72) comprises an inclined (diagonal) line forming a tooth (70e) and a notch (62e) in each corner area of the box (80).

In the box (80) of Figs. 8 and 13, each match line (72) comprises an inclined broken line forming a tooth (70e) and a notch (62e) in each corner area of the box (80).

In the boxes (80) of Figs. 10 to 12, each match line (72) comprises an inclined broken line forming at least two teeth (70e), optionally pointed, and at least two complementary notches (62e), in each corner area of the box (80).

In the boxes (80) of Fig. 14, each match line (72) comprises a curved inclined line forming at least two teeth (70e), optionally in the shape of a circular segment, and at least two complementary notches (62e), in each corner area of the box (80).

Advantageously, a plurality of teeth (70e) and complementary notches (62e) on each line of coincidence (72) increase the resistance of the box (80) to lateral horizontal forces.

Additionally, in the boxes (80) of Figs. 7-8 and 10-14, each corner zone has a sewing zone by ends of vertical glue cords (CC) parallel to each other and extending towards the coincidence line (72).

In Figs. 7-8 and 10-14, the tail cord ends (CC) include at least one tail cord end (CC) extended along at least one of said teeth (70e), and at least two other ends of tail cords (CC), one located on each side of the end of the tail cord (CC) extended along at least one of said teeth (70e).

Advantageously, by said extended arrangement of the tail cord ends (CC) at the link between the lower part of the lateral roof fins (70) and the upper part of the lateral ends of the first side panels (62) the stabilization is improved. the four vertical columns preloaded to increase the vertical compression resistance of the box (80).

Supplementary to the previous complementary option, Figs. 7-8 and 10-14 show that, in each corner area of the box, lower ends of a plurality of lower vertical tail cords (CC), arranged between each side flap (66) and each side roof fin ( 70), and upper ends of another plurality of vertical tail cords (CC), arranged between each side flap (66) and each lateral end of the first side panel (62), form a glue cord sewing area (CC ) parallel verticals extended along the tooth (70e) and the notch towards the coincidence line (72).

Advantageously, by means of said tail cord ends (CC) along at least one tooth (70e) and a notch (62e) in the link between the lower part of the lateral roof fins (70) and the upper part of the lateral ends of the side walls (62) further improves the stabilization of the four vertical columns to increase the vertical compression resistance of the box (80).

Preferably, Figs. 5 and 12 show that each corner area of the box (80) comprises a plurality of continuous vertical glue cords (CC) that extend a measure equal to the height of the box (60), from the first fold lines. longitudinal lines (64) connecting to the bottom panel (61) to the second transverse fold lines (69) connecting to the lateral roof fins (70), to increase the vertical compression resistance of the box (80). Each continuous vertical tail cord (CC) is formed by an upper tail cord (CC) segment disposed in the end flap (69), and a lower tail cord segment (CC) disposed in the first side panel (62). ), with the upper end of the lower tail cord segment (CC) connected to the lower end of the upper tail segment (CC).

Advantageously, these continuous vertical glue cords (CC) increase the compressive strength of the box (80) since they act as vertical reinforcement struts, in addition to the continuous vertical cardboard columns formed by lateral roof fins (70). and lateral ends of first side panels (62). Thanks to the push preload, the continuity of the glue cords (CC) is ensured along the height of the box (80), especially at the coincidence line (72), thus increasing the vertical compression resistance of the the box (80).

Preferably, in the boxes (80) of Figs. 7-8, 10-14 and 20:

the amount of glue (CC) of lower ends of upper glue cords (CC), mutually parallel and vertical, arranged between side flaps (66) and side roof fins (70) close to and/or coinciding with the lines of lower cut (70i),

and/or the amount of glue (CC) of some upper ends of other lower glue cords (CC), mutually parallel and vertical, arranged between side flaps (66) and lateral ends of the next second side panels (63) and/or or coincident with the upper cut lines (62s),

is greater than the amount of glue (CC) arranged along the vertical glue strands (CC) at positions further away from the coincidence line (72).

That is, the amount of glue (CC) of the glue cords (CC) arranged in the regions immediately adjacent to the coincidence lines (72), both below and above, is greater than the amount of glue (CC) in other vertical segments of the vertical tail cords (CC) further away from the coincidence line (72) according to the vertical direction (Z).

Advantageously, thanks to the push preload, the continuity of the glue cords (CC) is ensured along the height of the box (80), especially at the coincidence line 872), since the box (80) has preferably an accumulation of reinforcing glue (CC) caused by the push preload, thus increasing the vertical compression resistance of the box (80), since the vertical glue cords (CC) are reinforced at least some of their ends. , acting as vertical reinforcement struts, additional to the continuous vertical cardboard columns formed by lateral roof fins (70) and lateral ends of first side panels (62), which are now even more reinforced by this extra contribution / accumulation tail (CC) in the vicinity of the coincidence line (72).

Optionally, in Figs. 7-8, 10-14 and 17-20 the corrugation grooves (77) of the corrugated sheets (79) are parallel to the second fold lines (67) in the second side panels (63) and the side flaps (66 ) to increase the vertical compression resistance of the box (80).

Thus, the box has two mutually facing U's, each formed by a second side panel and two end flaps thereof, all of which have the grooves oriented vertically, in the direction where the corrugated cardboard is strongest, the flaps resting on the roof. of support in stacking on these high resistance U.

In another option, not shown in the figures, the corrugation grooves (77) of the corrugated sheets (79) are parallel to the vertical direction (Z) in the first side panels (62) and the side roof fins (70). to increase the vertical compression resistance of the box (80), increasing the resistance of the four columns preloaded by thrust, thus increasing the vertical compression resistance of the box (80).

In a preferred option, Figs. 4-8, 10-14 and 17-20 show that the first side panels (62) are larger than the second side panels (63).

Advantageously, in the optional case that the corrugation grooves (77) of the corrugated sheets (79) are vertical in the second side panels (63) and the side flaps (66), the box (80) offers an improvement in resistance of the box, and less deformation of the same under loads with first side panels (62) of greater size than the second side panels (63).

According to the second aspect of the present invention, reference 60 generically designates the plate (60) for forming a box (80).

The plate (60) of Figs. 1, 9 and 15 is flat and die-cut with weakened cut lines and fold lines.

In Figs. 1, 9 and 15, the plate (60) comprises a central bottom panel (61), delimited by two first longitudinal fold lines (64) mutually parallel and two first transverse fold lines (65) mutually parallel.

Likewise, the plate (60) comprises two first side panels (62) mutually facing each other, each connected by one of the first longitudinal fold lines (64) to the bottom panel (61).

Also, the plate (60) comprises two second side panels (63) mutually facing each other, each connected by one of the first transverse fold lines (65) to the bottom panel (61);

Likewise, the plate (60) comprises four side flaps (66). Each side flap (66) is connected by a respective second longitudinal fold line (67) to a respective lateral end of said second side panels (63).

Furthermore, the plate (60) comprises two roof flaps (68). Each roof flap (68) is connected by a respective second transverse fold line (69) to a respective top of one of said second side panels (63).

Also, the plate (60) comprises four lateral roof fins (70). Each lateral roof flap (70) is connected by a respective third longitudinal fold line (71) to a respective lateral end of the roof flaps (68).

Likewise, Figs. 2-3 and 17 show that the plate (60) has a double-wall corrugated cardboard sheet structure, with three smooth sheets (78) and two corrugated sheets (79), each corrugated sheet (79) being attached to two of the smooth leaves (78).

On plate (60), Figs. 1-3, 9, 15 and 17 show that the sum of:

- a first length (L1) coinciding with the transverse extension of the lateral roof fins (70); and of

- a second length (L2) coinciding with the transverse extension of the lateral ends of the first side panels (62);

is greater than a third length (L3) coinciding with the longitudinal separation distance between the second transverse fold line (69) and the first transverse fold line (65) in the second side panels (63).

In the sequence of Figs. 15-20, it is shown that in the plate (60), the first, second and third lengths (L1, L2, L3) are jointly configured to allow, during a bending of the side roof fins (70) and the first panels sides (62) of the plate (60), pressurize the lateral roof fins (70) and the lateral ends of the first side panels (62) by mutual pushing thereof, in respective four coincidence lines (72) , each match line (72) including a lower cut line (70i) of a lower end of one of the lateral roof fins (70) and an upper cut line (62s) of a lateral end of one of the first side panels (62), to increase the vertical compression resistance in the four corner areas of the sheet (60) in the folded state, and to allow said preload to be maintained and increased during bending of the lateral roof fins (70) and the first side panels (62) towards their vertical folded positions, as shown in Fig. 20.

Preferably, Figs. 1-3, 9, 15 and 17 show that in the plate (60), the corrugation grooves (77) of the corrugated sheets (79) are parallel to the second fold lines (67) in the second side panels (63 ) and the side flaps (66), to increase the vertical compression resistance in the folded state of the plate (60), corresponding to a box (80).

The third aspect of the present invention relates to the method of forming boxes (80) by folding and gluing flat sheets of die-cut cardboard (60) with weakened cutting lines and fold lines.

For the formation of each of the boxes (80) from a respective plate (60), for example, the formation of the box (80) of Fig. 4 from the plate (60) of Fig. 1, or for example the formation of the box of Fig. 10 from the plate of Fig. 9, the method comprises the steps of:

- fold two second side panels (63) mutually facing each other, each along a respective first horizontal transverse fold line (65) connecting to a central bottom panel (61), to a folded position where the second side panels (63) ) are vertical, perpendicular to the central background panel (61);

- fold four side flaps (66), along respective second horizontal fold lines (67) connecting the side flaps (66) to lateral ends of said second side panels (63), to a position where the side flaps (66) 66) are vertical, perpendicular to the two second side panels (63) and the central bottom panel (61);

- after the folding stage of the second side panels (63), fold two roof flaps (68) to positions where they are horizontal, along second horizontal transverse folding lines (69) connecting the roof flaps (68) to upper parts of the second side panels (63), to provide a support surface for stacking boxes (80); and

- pre-fold two first side panels (62) mutually facing each other, each along a respective first longitudinal fold line (64) connecting to the central bottom panel (61), until a pre-folded position where the first side panels (62) form first diagonal inclinations converging towards the bottom panel (61)

- pre-fold four lateral roof flaps (70), each along a respective third horizontal longitudinal fold line (71) connecting to a respective lateral end of the roof flaps (68), until a pre-folded position where lateral roof flaps (70) form second diagonal inclinations converging towards said horizontal roof flaps (68).

Said steps may optionally be executed with the mold (30) and/or the machine of Figs. 15 and 16.

After executing the aforementioned steps, the partially formed box (80) adopts the shape shown in Fig. 17, to initiate a subsequent bending of the lateral roof fins (70) and the first side panels (62) from the pre-positions. -diagonal folds of Fig. 17 towards vertical folded positions of Figs. 16 and 20, where the lateral roof fins (70) and the first side panels (62) are positioned vertically simultaneously and preloaded under pressure.

The sequence of Figs. 18-20 show that the method further comprises the step of pressurizing by mutual thrust at a respective match line (72) of each side roof fin (70) and each side end of the first side panels (62).

The Figs. 1, 9 and 17 show that each match line (72) includes a lower cut line (70i) of a lower end of one of the side roof fins (70) and includes an upper cut line (62s) of a lateral end of one of the first side panels (62).

Likewise, in the method, the sequence of Figs. 18-20 shows that said preload stage is maintained and increased during a bending of the lateral roof fins (70) and the first side panels (62) from the diagonal pre-bent positions towards vertical folded positions, where the fins roof sides (70) and the first side panels (62) are positioned vertically simultaneously and preloaded with said pressure.

Also, once the lateral roof fins (70) and the first side panels (62) are positioned in their vertical folded positions of Fig. 20, the method comprises the step of pressing and joining with vertical glue cords (CC). the lateral roof fins (70) and the lateral ends of the first side panels (62) on the vertical side flaps (66), the lateral roof fins (70) and the ends being simultaneously positioned vertically and preloaded under pressure sides of the first side panels (62), to increase the vertical compression resistance in four corner areas of the box (80).

In Fig. 18, during the bending of the lateral roof fins (70) and first side panels (62), along their respective longitudinal and horizontal folding lines (71, 64), the lower and upper ends of these parts of the box (80) being formed contact.

Subsequently, in Fig. 19, P1 generically designates a preload by thrust pressure of the lateral roof fin (70) on the end of the first side panel (62), while P2 generically designates a preload by thrust pressure of the lateral roof fin (70) on the end of the first side panel (62), during the folding of the lateral roof fins (70) and first side panels (62), along their respective longitudinal fold lines (71,64). and horizontal.

In Fig. 19, the thrust pressure between side roof fins (70) and first side panels (62) is continuous and increases progressively, for example, from a first thrust pressure (P1, P2) of Fig. 19 until a subsequent second push pressure (P1', P2') final of Fig. 20.

In Fig. 20, the vertical side roof fins (70) are preloaded by the second vertical thrust pressure (P2'), aligned with the vertical direction (Z), exerted by the ends of the first side panels (62). . Likewise, in Fig. 20, the first side panels (62) are preloaded by the second vertical thrust pressure (P1'), aligned with the vertical direction (Z), exerted by the vertical side roof fins (70).

In Figs. 19 and 20, said preload by thrust pressure between parts of the box (80) is prior to a subsequent pressure union of vertical glue cords (CC) of the lateral roof fins (70) and the lateral ends of the first side panels (62) on the side flaps (66).

Thus, in Figs. 4-8, and 10-14 and 20, once the box (80) is assembled, said push pressure preload on the four lateral roof fins (70) and the four lateral ends of the first side panels (62) , provides four continuous pressure preloaded vertical columns joined by the pressure preload at the four mating lines (72).

Said preloaded parts of the box are represented in Fig. 20 with the thrust pressures (P1', P2') vertical.

Following the boxes (80) of Figs. 4-8, and 10-14 and 20, each match line (72) includes a lower cut line (70i) of a lower end of one of the side roof fins (70) and an upper cut line (62s ) of a lateral end of one of the first side panels (62).

In Figs. 17-20, said preload occurs during a bending of the lateral roof fins (70) and the first side panels (62), shown in the sequence of Figs. 18, 19 and 29, by the third longitudinal fold lines (71) and by the first longitudinal fold lines (64), respectively.

In Figs. 17-20, said preload occurs before the subsequent union with vertical glue cords (CC), shown in Figs. 4-8, 10-14 and 20, of the four lateral roof fins (70) and the four lateral ends in pairs in each corner of the first side panels (62), so that said vertical preload is permanent once the box (80) is assembled, whether the box (80) is forming part of a vertical stack of boxes (80) or if it is not in a stacking situation, thus achieving a real and effective increase in the compression resistance of the box ( 80), providing said double wall thickness in each corner area of the box (80) with an additional reinforced support surface against vertical loads.

In the sequence of Figs. 18-20, with the continued preload in lateral roof fins (70) and lateral ends of first side panels (62), the upper ends of the lateral roof fins (70) connecting to the longitudinal fold lines (71) They are slightly displaced upward by the lateral ends of the first side panels (62), until the upper ends of the side roof fins (70) are vertically level or slightly above the horizontal roof flaps (68) in the box (80). ) obtained from Fig. 20.

In the sequence of Figs. 18-20, with continued preload on roof side fins (70) and side ends of first side panels (62), the lower ends of the side ends of the first side panels (62) are moved downward until they are vertically level or slightly below the lower face of the bottom panel (61) in the box (80) obtained from Fig. 20.

In Fig. 19, the first and second lengths of Fig. 18 are optionally reduced via a progressive reduction of the lower and upper roundness of the horizontal longitudinal fold lines (71, 64).

Preferably, said steps of preloading, bending and joining of lateral roof fins (70) and lateral ends of first side walls (62) may be implemented by any one of the embodiments of the forming assembly of the fourth aspect of the invention, of the mold. (30) of the fifth aspect of the invention, and/or the machine of the sixth aspect of the invention, described below.

Preferably, in the method, Figs. 4-8, 10-14 and 20 show that each lower cut line (70i) comprises a first inclined line, and each upper cut line (62s) comprises a second inclined line complementary to the first inclined line. Furthermore, each First and second lines together form a tooth (70e) with a crest and a notch (62e) with a valley, mutually complementary.

Following this preferred option, Figs. 18-20 show that the method also comprises the step of engaging the ends formed by the first inclined line with the ends formed by the second inclined line during the pressure preloading stage by mutual thrust between each lower cutting line (70i) and upper cut line (62s).

That is, the embedding stage is initiated in Fig. 18, and maintained during the folding of the lateral roof fins (70) and the first side panels (62) of Figs. 18-20, until the connection with glue cords (CC) of the lateral roof fins (70) and the lateral ends of the first side panels (62) on the side flaps (66) of Fig. 20.

Advantageously, the inclined line of each match line (72) provides in the teeth (70e) and notches (62e) an improved compression and/or lateral resistance since due to said inclination of the match lines (72) in a direction other than a direction parallel to the grooves (77) of the corrugated cardboard sheets, at the coincidence line (72) the fins (70) and first side panels (62) are pushed together through a corrugated sheets cut in die-cutting with inclined cutting lines, where the smooth and corrugated sheets (78, 79) of the cardboard structure offer greater resistance.

Advantageously, the teeth (70e) and notches (62e) are self-guided in a horizontal direction, for example, the longitudinal direction (X) of the figures, for their mutual coupling during bending, avoiding unwanted overlaps of lateral roof fins (70 ) and lateral ends first side panels (62).

Preferably, the method further comprises the step of, in the corner areas of the box, forming sewing areas by parallel vertical glue cords (CC) extending along the teeth (70e) and notches (62e) towards the lines coincidence (72).

Advantageously, by said extended arrangement of the glue cords (CC), at the link between the lower part of the lateral roof fins (70) and the upper part of the lateral ends of the side walls (62), the stabilization of the four vertical columns to increase the vertical compression resistance of the box (80).

Optionally, the method further comprises the step of increasing the amount of glue (CC) of the glue beads (CC) arranged in the regions immediately adjacent to the match lines (72) during the push pressure preloading step, such as As can be seen from Figs. 1, 4 and 15-20.

Advantageously, thanks to the push preload, the continuity of the glue cords is ensured along the height of the box (80), especially at the coincidence line (72), where the box (80) has an accumulation of reinforcement tail (CC) caused by the thrust preload, thus increasing the vertical compression resistance of the box (80), since the continuous vertical tail cords (CC) that act as vertical reinforcement struts, additional to The continuous vertical cardboard columns formed by lateral roof fins (70) and lateral ends of first side panels (62), are now even more reinforced by this extra addition/accumulation of glue (CC) in the vicinity of the coincidence line. (72).

Additionally, in the method, in the folding stage of the lateral roof fins (70) and the lateral ends of the first side panels (62), a bending start order is pre-established, where the lateral ends of the first panels The lateral roof fins (62) are initially pushed prior to a subsequent initial push of the lateral roof fins (70), as shown in the sequence of Figs. 17-18.

Advantageously, productive stops, costs and losses associated with a "stranding / enjambment" effect are reduced where the parts of the box (80) are not bent around their bending lines, due to the initial contact angulation of the forming piece with the part of the box (80) to be molded, such parts of the box (80) being on end, making the correct formation of the box impossible, causing box losses (80).

Referring to Figs. 17-20, this intentional predefined order is because a first length (L1) coinciding with the transverse extension of the lateral roof fins (70) (fin height) may be less than a second length (L2) coinciding with the transverse extension of the lateral ends of the first side panels (62) (height lateral ends of the first side panels).

Preferably, the box (80) of the first aspect of the invention can be obtained with the method of the third aspect of the invention.

Optionally, after forming the box (80), by folding and joining by pressure of glue cords (CC), the method also includes the step of containing fruit and vegetable products. Thus, the losses of boxes (80) containing horticultural products are reduced, since the folding and pressing operations for forming the box (80) cannot damage the contained product in any way, since horticultural products, for example, fruits and/or vegetables are housed in the cavity of the box after the formation of the box (80).

According to a fourth aspect, the present invention presents a shaping assembly, shown in Figs. 17-26.

The Figs. 15-20 and 17-26 show that the molding assembly is intended to be installed in a mold (30) of a machine for forming cardboard boxes (80) from plates (60), the mold (30) comprising a plurality of benders (31, 32, 33, 34) arranged around a cavity for forming the boxes (80), which at least partially delimit a perimeter of the cavity comprising four sides, two larger and two smaller, mutually facing each other by pairs, forming a molding tunnel with an essentially rectangular perimeter, configured to form boxes with a polygonal cross section, for example, rectangular or octagonal.

The assembly of Figs. 17-26 is configured to bend parts of each of the plates (60) with respect to others, in cooperation with a core (20) of the machine shown in Figs. 15 and 16. Such a core (30) is intended to be faced vertically with the mold (30) and the core is provided to be moved linearly in (Fig. 16) and out (Fig. 15) of the mold cavity (30). ) to push at least a portion of a bottom panel (61) of the plate (10) into the cavity (30).

Commonly to all embodiments, Figs. 16-20 and 25-26 show that the shaping assembly comprises two shaping devices (40) mutually facing each other and separated by a transverse separation distance, according to the transverse direction (Y) of the figures. The two shaping devices (40) are arranged around the cavity on mutually facing larger sides thereof.

The Figs. 17-26 show that each shaping device (40) comprises a first shaping section (41) and a linear drive (43). Each first shaping section (41) has a first vertical shaping surface (41a) movable guided by a respective linear drive (43) associated with at least one first horizontal guide (43c) along a transverse linear direction (Y), between a first receiving position shown in Figs. 17, 25 and 26 and an active position shown in Fig. 20.

Optionally, each at least one first horizontal guide (43a) may be an element that forms an integral part of the linear drive (43), as shown in the figures, or in an option not shown in the figures, it may be an external element. coupled to the linear drive (43).

In the examples of Figs. 17-26, the linear drive (43a) comprises an internally guided fluid dynamic cylinder that integrates at least a first horizontal guide (43c) of a movable piston along a cavity of a cylinder body.

In the examples of Figs. 17-26, each fluid dynamic cylinder integrates two first horizontal guides (43c).

In an option not shown in the figures, the linear drive (43) includes a fluid dynamic cylinder whose piston is not internally guided but which has coupled to its piston a horizontal guide or rod arranged externally to the cylinder body to guide the cylinder piston.

In the forming set of Figs. 17-26, each shaping device (40) further comprises a second shaping section (42). Each second shaping section (42) has a second vertical shaping surface (42a) connected to at least one second horizontal guide (46). Each second molding section (42) has a connected recovery element (44) for positioning the second molding section (42) in a second reception position, shown in Figs. 17, 25 and 26.

In Figs. 17-25, the connection between the second vertical molding surface (42a) and at least the second horizontal guide (46) is direct, joining one element to another.

Alternatively, in an option not shown, the connection between the second vertical shaping surface (42a) and at least the second horizontal guide (46) may be indirect, joining one element to another through intermediate elements.

The connection between the second vertical molding surface (42a) and the recovery element (44) may be direct, joining one element to another, as shown in Figs. 17-20 and 26, or indirect, joining one element to another through intermediate elements, as shown in Fig. 25, where, for example, the at least one second horizontal guide (46) acts as an intermediate joining element.

The Figs. 17-20 show that, in each shaping device (40) of the forming device, the second shaping section (42) is movable by the linear drive (43) according to the first transverse direction (Y), from the second receiving position of the Fig. 17, to the active position of the first shaping section (41), as shown in Fig. 20.

In Figs. 17-26, each return element (44) is embodied in a spring, for example, a helical compression spring.

Alternatively, in options not shown, each recovery element (44) can be embodied in a constant pressure cylinder, a fluid dynamic cylinder with a spring (for example, single-acting cylinders with spring), a fluid dynamic spring, for example, a spring tire, and/or a combination of these options, among other options.

In the shaping assembly, in the first and second shaping sections (41,42) in the receiving position of Figs. 17, 25 and 26, the first molding surfaces (41a) are separated from each other by a first separation distance (D1), and the second molding surfaces (42a) are separated from each other by a second separation distance (D2).

In the first and second receiving positions of Figs. 17, 25 and 26, the first and second separation distances (D1, D2) are of different measurements.

In Figs. 17, 25 and 26, the first and second shaping sections (41, 42) receive four lateral roof fins (70) pre-folded diagonally downward by third upper horizontal longitudinal fold lines (71), positionally delimiting them in their pre-position. -folded, with and/or without contact with them.

Likewise, in Figs. 17, 25 and 26, the first and second shaping sections (41, 42) receive four lateral ends of first side panels (62) pre-folded diagonally upward by first lower longitudinal fold lines (64), positionally delimiting them in their position pre-folded, with and/or without contact with them.

The Figs. 17-20 and 4-8, 10-14 and 20 show that in the first lower longitudinal fold lines (64), the third longitudinal fold lines (71) connect the four lateral roof fins (70) to lateral ends of two horizontal roof flaps (68), in turn connected to upper parts of two second vertical side panels (63) mutually facing each other, in turn connected by first transverse fold lines (65) to a central bottom panel (61), and where the first longitudinal fold lines (64) connect the first side panels (62) mutually facing each other to the bottom panel (61).

In Fig. 17, in the first and second receiving positions of the first and second shaping sections (41, 42), the first separation distance (D1) is greater than the second separation distance (D2) according to the transverse direction ( AND).

In the third embodiment of the forming assembly of Fig. 26, in the first and second receiving positions of the first and second shaping sections (41, 42), the first separation distance (D1) is greater than the second separation distance ( D2) according to the transverse direction (Y).

Commonly to all embodiments of Figs. 17-26, in each molding device (40) of the molding assembly, the first and second molding sections (41, 42) are jointly joined (in an integral manner) from intermediate positions thereof to the active position common to both, during a path of the movements of the first and second shaping sections (41, 42) according to the horizontal linear direction (Y), as shown in Figs. 18-20.

From the intermediate positions of the first and second shaping sections (41, 42) of Figs. 18 and 19 to their active position in Fig. 20, the first separation distance (D1) between first molding surfaces (41a) is equal to the separation distance (D2) between second molding surfaces (42a).

In these intermediate positions of Figs. 18-19, the first and second shaping sections (41, 42) bend the side roof fins (70) and the first side panels (62), and during said bending, continuously pressure preload by mutual thrust, in a respective line matching (72) each lateral roof fin (70) and each lateral end of the first side panels (62).

In Figs. 18-20, the shaping assembly preloads each match line (72) arranged between each lower cut line (70i) at the lower ends of the side roof fins (70) and each upper cut line (62s) of the ends sides of the first side panels (62).

In the active position of Fig. 20, the first separation distance (D1) between first molding surfaces (41a) is equal to the second separation distance (D2) between second molding surfaces (42a).

In the active position of Fig. 20, the first separation distance (D1) is equal to the second separation distance (D2), and the first and second shaping sections (41, 42) are jointly configured to simultaneously press together of vertical tail cords (CC), the lateral roof fins (70) and the first side panels (62), against four vertical side flaps (66) connected, by second vertical fold lines (67), to respective lateral ends of the second side panels (63) of the box (80).

In the shaping assembly, once the first and second shaping sections (41, 42) are in the active positions for said union for a pre-established time, the movable parts (43b) of each linear drive (43) are moved to respective first positions. reception, moving the first molding sections (41) to the first reception positions, and each respective second molding section (42) is moved by the recovery element (44) to its second reception position, leaving the molding assembly in the position of Figs. 17, 25 and 26.

In the shaping assembly, in the option not shown in the figures, that a return element (44) is a spring of a single-acting fluid dynamic cylinder, the positioning of the cylinder piston from a retracted position to an extended position is by the linear drive (43) and not by pressure of a fluid on the piston, that is, this single-acting cylinder has the supply of pressurized fluid canceled to achieve the integral union between first and second molding sections (41, 42). Continuing with this option not shown, the recovery of the position of the plunger in a retracted or extended position (corresponding to the reception position) is determined by a spring connected at one end to the plunger and at the other end to a part fixed to the body of the plunger. cylinder.

Preferably, in Figs. 15-20, 25 and 26, the shaping assembly comprises four shaping devices (40) mutually facing each other in pairs on the two mutually facing major longitudinal sides of the cavity. In Figs. 15-20, 25 and 26, each shaping device (40) is located in a corner area of the cavity associated with a respective lateral end of a longer longitudinal side, configured to individually form a respective lateral roof fin (70) and a respective lateral end of the first side panels (62) in a respective corner area of the box (80).

Advantageously, thanks to the number and arrangement of the number of shaping devices, the bending, push preloading, and pressure bonding of glue strands (CC) is carried out in a dedicated manner in each corner area, that is, individually, enabling the formation of boxes (80) even with possible tolerances / deformations of some corner areas of the box with respect to others, and/or enabling the formation of boxes (80) even in the event of defective positional adjustments of the forming assembly or forming assembly elements with respect to the cavity, by the workers, reducing production stops and reducing production costs.

In an optional advantage, this preferable option allows reducing production times of boxes (80) with different measurements, thanks to the fact that the arrangement and number of shaping devices enables their location in the corners of boxes of changing width and/or measurements. long, thus reducing the production times and costs of such boxes (80) of different sizes.

Optionally, in the forming assemblies of Figs. 17-26, each linear drive (43) of each shaping device (40) comprises a fluid dynamic cylinder provided with a fixed part (43a) and a movable part (43b) with respect to the fixed part connected to the first shaping section (41). .

In the figures, the fixed part (43a) corresponds to the body of the cylinder and the movable part (43b) corresponds to a cylinder rod guided by at least a first horizontal guide (43c).

Advantageously, these linear drives (43) are a simple and effective solution for the integral union between each pair of first and second shaping sections (41, 42), resulting in adequate synchronism between first and second shaping sections (41, 42) of each shaping device (40) of the forming assembly, with minimal maintenance/adjustment, not necessarily requiring the intervention of highly qualified workers, reducing production stops and reducing production costs.

Optionally, in Figs. 17-26, each return element (44) of each shaping device (40) comprises a compression spring having a front end attached, directly or indirectly, to the second shaping section (42), and having a rear positioning end fixed during forming.

Advantageously, the use of compression springs as recovery elements (44) of the shaping devices (40) are a simple and effective solution for the integral connection between each pair of first and second shaping sections (41, 42), resulting in an adequate synchronization between first and second shaping sections (41, 42) of each shaping device (40) of the shaping assembly, with minimal maintenance/adjustment, not necessarily requiring the intervention of highly qualified workers.

Additionally, in each shaping device (40) of Figs. 17 to 26, the second shaping section (42) is movable by a push of the first shaping section (41) movable by the linear drive (43) according to the first transverse direction (Y), from the second receiving position to the position active of the first shaping section (41).

Advantageously, this configuration of first and second molding sections (41, 42) of the molding devices (40) is a simple and effective solution for the integral connection between each pair of first and second molding sections (41, 42), resulting in a adequate synchronism between first and second shaping sections of each shaping device (40) of the shaping assembly, with minimal maintenance/adjustment, not necessarily requiring the intervention of highly qualified workers.

Optionally, each first shaping section (41) comprises a recess (41b) configured so that the first and second surfaces (41a, 42a) of the first and second shaping section (41) of each shaping device (40) are contained in the same vertical plane during the dragging movement of the second shaping section (42) by the linear drive (43) of the first shaping section (41).

Optionally, in each shaping device (40) of the shaping assembly, during a path of the first shaping sections (41) from the retracted positions of Fig. 17 to just before the intermediate position of Fig. 18, the first and second The shaping sections (41, 42) are not joined together, but the first shaping section (41) is moved by the linear drive (43) from the first retracted position to intermediate positions while the second shaping section (42) remains in the second. retracted position. Subsequently, the first and second shaping sections (41, 42) of each shaping device (40) are integrally joined during the subsequent journey from the intermediate positions to the active position, optionally by drag, as described above.

Additionally, Figs. 21-24 show that the at least second horizontal guide (46) passes through through holes (45a) of an auxiliary support (45), to guide the at least second horizontal guide (46) transversely, that is, according to the transverse direction. (AND).

Additionally, in Figs. 17-26, each shaping device (40) is mounted on a respective base support (37). For example, Figs. 21-24 show that screws (47) fix the fixed part (43) of the linear drive (43) to the base support (37) and auxiliary screws (48) fix the auxiliary support (45) to the base support (37). .

Optionally, each shaping device (40) may comprise a first positioning device comprising a transverse guide aligned with the transverse direction (Y), wherein the screws (47) are locked and released in positions along it, to change the position of the first molding sections (41) according to the transverse linear direction (Y) towards or away from the mold cavity (30).

Said transverse guide, not shown in the figures, may be arranged on the base support (37).

Optionally, each shaping device (40) may comprise a second positioning device comprising a second transverse guide aligned with the transverse direction (Y), wherein the auxiliary screws (48) are locked and released in positions along it. , to change the position of the second molding sections (42) according to the transverse linear direction (Y) towards or away from the mold cavity (30).

Said second transverse guide, not shown in the figures, may be arranged on the auxiliary support (45).

According to a fifth aspect, reference 30 generically designates the mold (30) for a box forming machine (80) from flat cardboard sheets (60) of the fifth aspect of the invention, shown in Figs. 15-26.

The Figs. 15 and 16 show that the mold (30) comprises a plurality of benders (31, 32, 33, 34) arranged around a cavity for forming the boxes (80), at least partially delimiting a perimeter of four sides of the cavity. , configured to bend some parts of the plates (60) with respect to others in cooperation with a male (20) of the machine movable in and out of said cavity.

The Figs. 15 and 16 show that the plurality of benders (31, 32, 33, 34) comprises two first bending devices (31) mutually facing a first distance (D1) greater than the width of the box (80), to pre-fold two first side panels (62) mutually facing each other, each along a respective first longitudinal fold line (64) connecting to the central bottom panel (61), up to a pre-folded position where the second side panels (63) form first diagonal inclinations converging towards the background panel (61).

Optionally, each first bending device (31) is embodied in a respective first plate, optionally curved as shown in the figures, and/or inclined, each bending device (31) including a vertical bending portion (31a).

Preferably, Figs. 17-20 and 25-26 show that a third transverse separation distance (D3) between the two bending devices (31) of each shaping device (40) is equal to or greater than the first and/or second separation distance (D1, D2).

Optionally, the plurality of benders (31, 32, 33, 34) comprises four first bending devices (31) facing each other in pairs.

In Figs. 15 and 16, the plurality of benders (31, 32, 33, 34) also comprises two mutually facing second bending devices (32), for folding two mutually facing second side panels (63), each along a respective first fold line horizontal transversal (65) connecting to a central bottom panel (61), to a folded position where the second side panels (63) are vertical.

Optionally, each second bending device (32) is embodied in a respective second plate, optionally inclined as shown in the figures, and/or curved.

Optionally, the plurality of benders (31, 32, 33, 34) comprises four second bending devices (32) facing each other in pairs.

Continuing in Figs. 15 and 16, the plurality of benders (31, 32, 33, 34) also comprises four third bending devices (33) located in corners of the mold, sandwiched between a first and second bending device (31, 32), to bend four side flaps (66), by respective second longitudinal and horizontal folding lines (67) connecting the side flaps (66) to lateral ends of said second side panels (63), to a position where the side flaps (66) ) are vertical.

Optionally, each third bending device (33) is embodied in a respective third plate or plate, optionally curved as shown in the figures, and/or inclined.

Following in Figs. 15 and 16, the plurality of benders (31, 32, 33, 34) also comprises four fourth bending devices (34) located in the corners of the mold, sandwiched between a first and second bending device (31, 32), to pre- bend lateral roof flaps (70), each along a respective third horizontal longitudinal fold line (71) connecting to a respective lateral end of the roof flaps (68), to a pre-folded position where the second panels sides (63) form second diagonal inclinations converging towards said horizontal roof flaps (68).

Optionally, each fourth bending device (34) is embodied in a respective fourth plate or plate, optionally curved as shown in the figures, and/or inclined.

Optionally, the plurality of benders (31, 32, 33, 34) also comprises two mutually facing fifth bending devices (35, 36), configured to fold two roof flaps (68) to positions where they are horizontal, along second lines of horizontal transverse folds (69) connecting the roof flaps (68) to the upper parts of the second side panels (63).

Optionally, each fifth bending device (35, 36) is materialized in a respective fifth plate or plate (35), preferably flattened as shown in the figures, and a horizontal axis (36) coupled to the fifth plate or plate to move it articulately between a retracted position outside the cavity (not shown), and a horizontal position inside the cavity shown in Fig. 16.

The Figs. 15 and 16 show that the mold (30) also comprises the molding assembly of the four aspect of the invention, previously described, and located with respect to the first benders (31) of the mold (30) in Figs. 17-20, 25 and 26.

According to a fifth aspect, reference 100 generically designates a machine for forming boxes (80) from flat cardboard sheets (60) of the sixth aspect of the invention, shown for example in Figs. 15 and 16.

The Figs. 15 and 16 show that the machine comprises a plate conveyor, including a pusher (11), movable by a conveyor drive, preferably a rotating electric motor, and arranged between two lateral guides (13), preferably horizontal, for linear conveying. plates (60) one by one, from an origin position, to a stop position where the plate (60), optionally stopped by front stops (14), is sandwiched between a male (20) and a mold (30) mutually facing each other vertically according to the vertical direction (Z).

Following in Figs. 15 and 16, the machine further comprises a gluing device that includes a plurality of glue injectors (15) configured to apply glue beads (CC) on the plates (60) during their transportation along the conveyor.

The gluing device includes a plurality of hoses (17) connected to a plurality of glue application nozzles (16), vertically spaced a separation distance from the horizontal side guides (13).

Likewise, the machine comprises said male (20), linearly movable between a position inside the mold cavity (30) shown in Fig. 16, and a position outside the mold cavity (30) shown in Fig. 15. , by a male drive, preferably a rotating electric motor, which guides a vertical guide (21) at the end of which the male (20) is mounted.

The male (20) has a pushing surface (21) configured to at least partially push the bottom panel (61) of the plate (60) into the cavity.

Optionally, the male (20) comprises a plurality of side walls (22) to cooperate in the formation of the box (80) with the mold (30).

Likewise, the core (20) comprises at least two retractable elements (23) mutually facing each other longitudinally, between a working position where they help to fold the folding lines (64, 65) delimiting the bottom panel (61) of the plate (60), and a retracted position (not shown) to enable the extraction of the male (20) from the inside of the box (80) formed with the roof flaps (68), as shown in Fig. 16.

Likewise, the machine comprises the mold (30) of the fifth aspect of the invention shown in Figs. 17-20.

The scope of the present invention is given by the following claims.

Claims (18)

1.- Cardboard box (80) obtained by folding and gluing a flat sheet (60), die-cut with weakened cutting lines and folding lines, the box (80) comprising: a central background panel (61), delimited by two first mutually parallel longitudinal fold lines (64) and two first mutually parallel transverse fold lines (65); two first side panels (62) mutually facing each other, each connected by one of the first longitudinal fold lines (64) to the bottom panel (61), and two second side panels (63) mutually facing each other, each connected by one of the first transverse fold lines (65) to the bottom panel (61), where the first and second side panels (62, 63) are folded by the first fold lines (64, 65) and arranged around the bottom panel (61), forming four side walls, facing each other in pairs, which define four corner areas of the box (80), and together with the bottom panel (61) form a cavity to contain products; four side flaps (66), each side flap (66) being connected by a respective second vertical fold line (67) to a respective lateral end of said second side panels (63), and each side flap (66) being attached and joined with glue (CC) to the first side panels (62), to link the first side panels (62) with the second side panels (63); two horizontal roof flaps (68), each roof flap (68) being connected by a respective second transverse fold line (69) to a respective top of one of said second side panels (63); and four lateral roof flaps (70), each connected by a respective third horizontal longitudinal fold line (71) to a respective lateral end of the roof flaps (68) and joined with glue (CC) to one of the side flaps ( 66); characterized by that the box (80) has a double-walled corrugated cardboard sheet structure, with three smooth sheets (78) and two corrugated sheets (79), each corrugated sheet (79) being attached to two of the smooth sheets (78). ), to increase the resistance of the box (80); because in the initially deployed state of the box (80), corresponding to a flat plate (60), the sum of: - a first length (L1) coinciding with the transverse extension of the lateral roof fins (70); and of - a second length (L2) coinciding with the transverse extension of the lateral ends of the first side panels (62); is greater than a third length (L3) coinciding with the longitudinal separation distance between the second transverse fold line (69) and the first transverse fold line (65) in the second side panels (63), and whereby the four lateral roof fins (70) and the four lateral ends of the first side panels (62), due to said relationship between first, second and third lengths (L1, L2, L3), are preloaded to vertical pressure (P2', P1') by mutual push in four coincidence lines (72), prior to the pressure union of vertical glue cords (CC) of the lateral roof fins (70) and the lateral ends of the first side panels (62) on the side flaps (66), each match line (72) including a lower cut line (70i) of a lower end of one of the side roof fins (70) and an upper cut line (62s) of a lateral end of one of the first side panels (62), to increase the strength of the box (80) in the four corner areas. 2. - Box (80) according to claim 1, wherein each lower cut line (70i) and each upper cut line (62s) is a horizontal rectilinear line, each match line (72) being a horizontal rectilinear line. 3. - Box (80) according to claim 1, wherein each match line (72) comprises an inclined line, each lower cut line (70i) comprising a first inclined line, and each upper cut line (62s) comprises a second inclined line complementary to the first inclined line, each first and second line jointly forming a tooth (70e) with a crest and a notch (62e) with a valley, mutually complementary, to engage the ends formed by the first inclined line with the ends formed by the second inclined line during the mutual thrust between each lower cut line (70i) and upper cut line (62s), prior to the union with glue cords (CC) of the lateral roof fins (70 ) and the lateral ends of the first side panels (62) on the side flaps (66) and during folding of the side roof fins (70) and the first side panels (62). 4. - Box (80) according to claim 3, wherein each corner area has a sewing area for ends of vertical glue cords (CC) parallel to each other and extended towards the coincidence line (72), which include at least one end of tail cord (CC) extended along at least one of said teeth (70e), and including at least two other ends of tail cords (CC), one located on each side of the end of the tail cord (CC) extended along at least one of said teeth (70e). 5. - Box (80) according to claim 4, wherein, in each corner area, lower ends of a plurality of lower vertical tail cords (CC), arranged between each side flap (66) and each side fin of roof (70), and upper ends of another plurality of vertical glue cords (CC), arranged between each side flap (66) and each lateral end of the first side panel (62), form a glue cord sewing area (CC) parallel verticals extended along the tooth (70e) and the notch (62e) towards the match line (72). 6. - Box (80) according to any one of the preceding claims 1 to 3, wherein each corner area comprises a plurality of continuous vertical glue cords (CC) that extend a measure equal to the height of the box (60). ), from the first longitudinal fold lines (64) connecting to the bottom panel (61) to the second transverse folding lines (69) connecting to the end flaps (70), to increase the vertical compression resistance of the box (80), and where each continuous vertical tail cord (CC) is formed by an upper tail cord segment (CC) arranged in the end flap (69), and a lower tail cord segment (CC) arranged in the first side panel (62), the upper end of the lower tail cord segment (CC) being connected to the lower end of the upper tail segment (CC). 7. - Box (80) according to any one of the previous claims, wherein the amount of glue (CC) of lower ends of upper glue cords (CC), mutually parallel and vertical, arranged between side flaps (66) and side roof fins (70) close to and/or coinciding with the lines of lower cut (70i), and/or the amount of glue (CC) of some upper ends of other lower glue cords (CC), mutually parallel and vertical, arranged between side flaps (66) and lateral ends of the second side panels (63) next to and/or coinciding with the upper cut lines (62s), is greater than the amount of glue (CC) arranged along the vertical glue cords (CC) in positions further away from the coincidence line (72) according to the vertical. 8. - Box (80) according to any one of the preceding claims, wherein the corrugation grooves (77) of the corrugated sheets (79) are parallel to the second fold lines (67) in the second side panels (63). and the side flaps (66) to increase the vertical compression resistance of the box (80). 9. - Box (80) according to any one of the preceding claims 1 to 7, wherein the corrugated grooves (77) of the corrugated sheets (79) are parallel to the vertical direction (Z) in the first side panels (62). ) and the side roof fins (70) to increase the vertical compression resistance of the box (80) 10. - Box according to any of the previous claims, wherein the bottom panel (61) is rectangular. 11. - Flat plate (60), die-cut with weakened cutting lines and folding lines, for the formation of a box (80), comprising: a central background panel (61), delimited by two first mutually parallel longitudinal fold lines (64) and two first mutually parallel transverse fold lines (65); two first side panels (62) mutually facing each other, each connected by one of the first longitudinal fold lines (64) to the bottom panel (61); two second side panels (63) mutually facing each other, each connected by one of the first transverse fold lines (65) to the bottom panel (61); four side flaps (66), each side flap (66) being connected by a respective second longitudinal fold line (67) to a respective lateral end of said second side panels (63); two roof flaps (68), each roof flap (68) being connected by a respective second transverse fold line (69) to a respective top of one of said second side panels (63); four lateral roof flaps (70), each connected by a respective third longitudinal fold line (71) to a respective lateral end of the roof flaps (68); and characterized by that the plate (60) has a double-walled corrugated cardboard sheet structure, with three smooth sheets (78) and two corrugated sheets (79), each corrugated sheet (79) being attached to two of the smooth sheets (78). ), to increase the vertical compression resistance in the folded state of the plate (60), corresponding to a box (80); because the sum of: - a first length (L1) coinciding with the transverse extension of the lateral roof fins (70); and of - a second length (L2) coinciding with the transverse extension of the lateral ends of the first side panels (62); is greater than a third length (L3) coinciding with the longitudinal separation distance between the second transverse fold line (69) and the first transverse fold line (65) in the second side panels (63); and because the first, second and third lengths (L1, L2, L3) are jointly configured to allow, during a bending of the side roof fins (70) and the first side panels (62) of the sheet (60), to preload pressure the lateral roof fins (70) and the lateral ends of the first side panels (62) by mutual pushing thereof, in respective four coincidence lines (72), each coincidence line (72) including a cutting line lower end (70i) of a lower end of one of the lateral roof fins (70) and an upper cut line (62s) of a lateral end of one of the first side panels (62), to increase the vertical compression resistance in the four corner areas of the sheet (60) in the folded state, and to allow said preload to be maintained and increased during the bending of the side roof fins (70) and the first side panels (62) towards respective folded positions. verticals of them. 12.- Molding assembly, intended to be installed in a mold (30) of a machine for forming cardboard boxes (80) from sheets (60), the mold (30) comprising a plurality of benders (31, 32). , 33, 34) arranged around a cavity for forming the boxes (80), which at least partially delimit a perimeter of the cavity that comprises four sides, two larger sides facing each other and two smaller sides facing each other, the forming assembly being configured to bending parts of each of the plates (60) with respect to others, in cooperation with a male (20) of the machine facing vertically with the mold (30) and linearly movable in and out of the cavity; the molding assembly comprising two molding devices (40) mutually facing each other and separated by a transverse separation distance, arranged around the cavity on the mutually facing major sides of the cavity, each shaping device (40) comprising a first shaping section (41), which has a first vertical shaping surface (41a), movable guided by a respective linear drive (43) associated with at least a first horizontal guide (43c) along a transverse linear direction (Y), between a first receiving position and an active position; the shaping set being characterized by Each shaping device (40) further comprises a second shaping section (42), having a second vertical shaping surface (42a), connected to at least a second horizontal guide (46) and connected to a positioning retrieval element (44). the second molding section (42) in a second reception position, the second molding section (42) being movable by the linear drive (43) according to the first transverse direction (Y), from the second reception position to the active position of the first shaping section (41); In the first and second receiving positions, the first molding surfaces (41a) are separated from each other by a first separation distance (D1) and the second molding surfaces (42a) are separated from each other by a second separation distance (D2), being the first and second separation distance (D1, D2) of different measurements, the first and second shaping sections (41, 42) being jointly configured to receive four lateral roof fins (70) pre-folded diagonally downward by third lines of upper horizontal longitudinal folds (71) and to receive four lateral ends of first side panels (62) pre-folded diagonally upward by lower first longitudinal fold lines (64), where the third longitudinal fold lines (71) connect the four lateral roof fins (70) to lateral ends of two horizontal roof flaps (68), in turn connected to upper parts of two second vertical side panels (63) mutually facing each other, in turn connected by first transverse fold lines ( 65) to a central bottom panel (61), and where the first longitudinal fold lines (64) connect the first side panels (62) mutually facing the bottom panel (61); The first and second shaping sections (41, 42) of each shaping device (40) are jointly joined from intermediate positions to the active position, during a path of the movements of the first and second shaping sections (41, 42) according to the horizontal linear direction (Y), the first separation distance (D1) being equal to the second separation distance (D2), and the first and second shaping sections (41, 42) being configured to fold the lateral roof fins (70 ) and the first side panels (62), and to, during said bending, continuously preload under pressure by mutual thrust, in a respective line of coincidence (72) of each lateral roof fin (70) and each lateral end of the first side panels (62), each coincidence line (72) being arranged between each lower cut line (70i) at the lower ends of the side roof fins (70) and each upper cut line (62s) of the side ends of the first side panels (62), and because in the active position, the first separation distance (D1) is equal to the second separation distance (D2), the first and second shaping sections (41,42) being jointly configured in the active position to simultaneously join by pressure of vertical glue cords (CC), the lateral roof fins (70) and the first side panels (62), against four vertical side flaps (66) connected, by second fold lines ( 67) vertical, to respective lateral ends of the second side panels (63) of the box (80). 13. - Molding assembly according to claim 12, comprising four molding devices (40) mutually facing each other in pairs on the two largest longitudinal sides mutually facing each other of the cavity, each molding device (40) being located in a corner area of the cavity. associated with a respective lateral end of a longer longitudinal side, configured to individually form a respective lateral roof fin (70) and a respective lateral end of the first side panels (62) in a respective corner area of the box (80) . 14. - Molding assembly according to any one of claims 12 or 13, wherein each linear drive (43) of each molding device (40) comprises a fluid-dynamic cylinder provided with a fixed part (43a) and a movable part (43b) with respect to to the fixed part connected to the first shaping section (41). 15. - Molding assembly according to any one of claims 12 to 14, wherein each recovery element (44) of each molding device (40) comprises a compression spring that has a front end attached, directly or indirectly, to the second section. molding (42) and having a rear end with a fixed position during forming. 16. - Molding assembly according to any one of claims 12 to 15, wherein, in each molding device (40), the second molding section (42) is movable by a push of the first molding section (41) movable by the drive linear (43) according to the first transverse direction (Y), from the second reception position to the active position of the first shaping section (41). 17. - Mold (30) for a box forming machine (80) from flat cardboard sheets (60), the mold (30) comprising a plurality of benders (31, 32, 33, 34) arranged around a cavity for forming the boxes (80), at least partially delimiting a perimeter of four sides of the cavity, configured to bend some parts of the plates (60) with respect to others in cooperation with a male (20) of the movable machine inside and outside said cavity; wherein the plurality of doublers (31, 32, 33, 34) comprises: two first bending devices (31) mutually facing each other a first distance (D1) greater than the width of the box (80), configured to pre-fold two first side panels (62) mutually facing each other, each along a respective first folding line longitudinal (64) connection to the central bottom panel (61), to a pre-folded position where the second side panels (63) form first diagonal inclinations converging towards the bottom panel (61); two mutually facing second bending devices (32), configured to fold two mutually facing second side panels (63), each along a respective first horizontal transverse folding line (65) connecting to a central bottom panel (61), until a folded position where the second side panels (63) are vertical, four third bending devices (33) located in corners of the mold, sandwiched between a first and second bending device (31, 32), configured to fold four side flaps (66), along respective second longitudinal and horizontal folding lines (67). connecting the side flaps (66) to lateral ends of said second side panels (63), to a position where the side flaps (66) are vertical; four fourth bending devices (34) located at the corners of the mold, sandwiched between a first and second bending device (31, 32), configured to pre-bend lateral roof fins (70), each along a respective third line of horizontal longitudinal fold (71) connecting to a respective lateral end of the roof flaps (68), to a pre-folded position where the second side panels (63) form second diagonal inclinations converging towards said horizontal roof flaps (68). ; two fifth mutually facing bending devices (35, 36), configured to fold two roof flaps (68) to positions where they are horizontal, by second horizontal transverse folding lines (69) connecting the roof flaps (68) to parts tops of the second side panels (63); characterized in that it comprises the molding assembly of any one of claims 12 to 16. 18.- Machine for forming boxes (80) from flat cardboard sheets (60), comprising: a plate conveyor that includes a pusher (11) movable between two lateral guides (13), configured to linearly transport plates (60) one by one from an origin position to a position where the plate (60) is sandwiched between a male (20) and a mold (30) facing each other vertically; a gluing device that includes a plurality of glue injectors (15) configured to apply glue beads (CC) on the plates (60) during their transportation along the conveyor; and said male (20), linearly movable in and out of a cavity of the mold (30), the male (20) having a pushing surface (21) configured to push the iron (60) into the cavity; characterized in that the mold (30) is according to claim 17.