Automatic pasting method and device for special-shaped box

Abstract

The application discloses an automatic pasting box method and equipment for a special-shaped box, and comprises the following steps: preparing a pasting surface paper according to an unfolded profile of a formed special-shaped box, the pasting surface paper comprising a center bottom area, linear parts located on opposite sides of the center bottom area, and curved parts corresponding to curved parts of the box body, a score line being arranged between the linear parts and the curved parts, and a plurality of cutting lines being arranged along the arc length direction of the curved parts, so that the curved parts can be segmented and deformed and can be adhered to the curved profile of the box body when being pushed. According to the application, the curved parts are segmented into a plurality of adhering small pieces by arranging a plurality of cutting lines along the arc length direction of the curved parts, and the adhering small pieces can be respectively adapted to folding deformation when being folded, so that wrinkles and edge lifting of the surface paper in the folding process are avoided, and the pasting quality of the curved folding part of the special-shaped box is remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of packaging-related technologies, and in particular to an automatic method and equipment for gluing irregularly shaped boxes. Background Technology

[0002] Boxes with round or curved edges, premium boxes, and irregularly shaped boxes are widely used in the packaging of cosmetics, electronic products, wines, gifts, and cultural and creative products. Compared to regular rectangular boxes, irregularly shaped boxes typically have rounded corners, curved edges, concave curves, convex curves, or box structures with continuous transitions between straight and curved sections. The pasting of the linerboard for these boxes requires not only that the straight edges be pasted flat, but also that the linerboard fold without wrinkling, curling, or misalignment when folded after passing through curved sections, placing high demands on the pasting process.

[0003] Currently, the gluing process for irregularly shaped boxes is mostly done manually. Operators need to hold the glued paper or use a simple pressure plate to press it onto the curved and folded parts of the box. Especially when folding at rounded corners or irregular arcs, the angle and tension of the paper need to be repeatedly adjusted, making the operation difficult and highly dependent on worker experience. This method suffers from low production efficiency, high labor intensity, poor consistency in gluing positions, and difficulty in controlling local wrinkles and glue overflow, making it unsuitable for large-scale production.

[0004] Existing automatic box gluing equipment is mainly designed for regular rectangular boxes. For irregularly shaped boxes with curved contours, due to the lack of suitable paper cutting design and automatic pasting methods, the paper is prone to wrinkles and curling edges due to cumulative deformation when folded after bending, making high-quality automatic box gluing impossible. Furthermore, existing automatic production solutions for irregularly shaped boxes mostly employ a process of folding paper and backing board onto a mold, where the paper and backing board are first bonded together and then folded together to form the box body, rather than gluing onto a pre-formed box. The technical approaches and the bonding challenges to be solved by these two methods are fundamentally different. The irregularly shaped box described in this invention specifically refers to an irregularly shaped box body with at least two parallel sides. This type of box can be pressed and glued from both sides using the mold structure of a top and bottom box gluing machine, exhibiting good automation adaptability. Summary of the Invention

[0005] In order to overcome the existing technical defects, the purpose of this invention is to provide an automatic gluing method and equipment for irregularly shaped boxes to solve the above-mentioned technical problems.

[0006] The technical solution adopted by this invention to solve the technical problem is as follows: According to one aspect of the present invention, an automatic gluing method for irregularly shaped boxes is designed, wherein the irregularly shaped box has at least two parallel sides, the method comprising the following steps: S1. Prepare a box-making paper according to the unfolded outline of the pre-formed irregular box. The box-making paper includes a central bottom-fitting area, straight sections on both sides of the central bottom-fitting area, and curved sections corresponding to the curved parts of the box body. An indentation line is provided between the straight sections and the curved sections. Several cutting lines are provided along the arc length direction of the curved sections so that the curved sections can deform in segments and conform to the curved outline of the box body when pushed. S2. Apply adhesive to the paper used for gluing the box; S3. Position the formed box body and the gluing paper in the gluing station of the top and bottom box machine; S4. The relative lifting mechanism of the box-making machine lifts the longer sides of the glued box paper relative to the box body. S5. Drive the first and second molds, which are set opposite to each other, to move towards each other in the direction close to the box body, so that the straight part of the paper pasted on both sides is attached to the side of the box body. S6. Before, during or at the end of the pressing process of the mold structure, the modular pusher structure set at the corresponding position of the box body bend pushes the bent part into the box bend, so that the glued paper is attached to the bent surface or the bent edge under the combined action of the cutting line and the indentation line. S7. Maintain pressure in the mold structure and pusher structure to hold pressure; S8. After the pressure holding period ends, the mold structure and pusher structure are reset in sequence to complete the automatic box gluing.

[0007] To better address the aforementioned technical deficiencies, the present invention also provides a more advanced technical solution: In some embodiments, the cutting lines are arranged at intervals along the arc length of the bend, cutting the bend into multiple independently deformable fitting pieces; the spacing between adjacent cutting lines is determined according to the radius of curvature of the bend in the box, the smaller the radius of curvature, the smaller the spacing between cutting lines, and the larger the radius of curvature, the larger the spacing between cutting lines.

[0008] In some embodiments, the depth of the crease line is 40% to 60% of the thickness of the box-making paper.

[0009] In some embodiments, the modular pusher structure includes a pusher base and one or more replaceable pusher blocks mounted on the pusher base, the end faces of which match the curved profile of the housing.

[0010] In some embodiments, both the first mold and the second mold are provided with straight pressing surfaces for pressing the straight portions of the glue box paper.

[0011] In some embodiments, the first mold and the second mold are further provided with arc-shaped pressing surfaces at positions corresponding to the bending points of the box body, for assisting in pressing or limiting the bending points of the box body.

[0012] In some embodiments, in S6, the pusher structure pushes the curved portion into the box-shaped curved portion during the mold structure pressing process.

[0013] In some embodiments, in step S2, the adhesive application method is roller coating, spraying, or hot melt adhesive coating.

[0014] An automatic gluing device for irregularly shaped boxes includes: The box-making machine has a gluing station and a relative lifting mechanism, which is used to lift the longer sides of the gluing paper relative to the box body. The mold structure, set at the box gluing station, includes a first mold and a second mold arranged opposite to each other, which can move towards each other in the direction close to the box body, and are used to press and paste the mounting paper on both sides of the box body to the side of the box body. The modular pusher structure is set at the corresponding position of the box body bend, and is used to push the curved part of the box face paper into the box bend and guide it to be glued.

[0015] In some embodiments, the modular pusher structure includes a pusher base and a replaceable pusher block mounted on the pusher base, the end face of the pusher block matching the curved profile of the housing.

[0016] The beneficial effects of this invention are as follows: This invention utilizes a series of cutting lines along the arc length of the curved portion of the box-making paper to divide the curved section into multiple independently deformable bonding pieces. During folding after bending, each bonding piece can adapt to the folding deformation, preventing wrinkles and curling edges caused by cumulative deformation of the paper during folding. This significantly improves the pasting quality at the curved and folded areas of irregularly shaped boxes. The invention also features an automated process where the first and second molds in a box-making machine automatically press and adhere the straight sections on both sides, transforming the pasting of straight edges from manual operation to automated execution. Combined with a modular pusher structure that pushes and guides the curved section during pressing, this achieves fully automated pasting of pre-formed irregularly shaped boxes from straight edges to curved edges, eliminating the need for manual intervention. This effectively solves the technical problem of difficult positioning and bonding of the paper at the curved and folded areas of irregularly shaped boxes. The modular pusher structure is equipped with replaceable pusher blocks. The pusher block end face matches the curved contour of the box body, and the pusher block of the corresponding specification can be replaced according to different box shapes. It is suitable for irregularly shaped boxes with different radii of curvature and bending angles, and has good versatility and flexibility in changing shapes. At the same time, the first mold and the second mold are provided with arc-shaped pressing surfaces at the positions corresponding to the bending points of the box body. They can assist in limiting and pressing the bending and folding points of the box body during the pressing process, ensuring that the bent part is further shaped and pressed after being guided by the pusher, and improving the bonding firmness. Compared with manual box gluing, this invention can be integrated into the continuous production cycle of the box gluing machine. The theoretical cycle can be increased from about 30-80 pieces / h for a single manual station to about 450-1200 pieces / h, which significantly improves production efficiency. At the same time, the consistency of the gluing position is stably maintained through the positioning mechanism and control program, effectively reducing the quality fluctuations caused by manual operation. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the irregular-shaped box cover paper of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the structure of the irregular-shaped box cover paper of the present invention. Figure 2 ; Figure 3 This is a schematic diagram of the structure of the first mold and the second mold of the present invention. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0019] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0020] In the description of this invention, unless otherwise explicitly defined, terms such as setting, installing, connecting, and fixing should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0021] refer to Figures 1 to 3 As shown, the present invention provides an automatic gluing method for irregularly shaped boxes, comprising the following steps: S1. Prepare a box-making paper according to the unfolded outline of the pre-formed irregular box. The box-making paper includes a central bottom-attaching area 1, straight sections 2 located on both sides of the central bottom-attaching area 1, and curved sections 3 corresponding to the curved parts of the box body. An indentation line is provided between the straight sections 2 and the curved sections 3. Several cutting lines 4 are provided along the arc length direction of the curved sections 3 so that the curved sections 3 can deform in segments and conform to the curved outline of the box body when pushed. S2. Apply adhesive to the paper used for gluing the box; S3. Position the formed box body and the gluing paper in the gluing station of the top and bottom box machine; S4. The relative lifting mechanism of the box-making machine lifts the longer sides of the glued box paper relative to the box body. S5. Drive the first mold 5 and the second mold 6, which are set opposite to each other, to move towards each other in the direction close to the box body, so that the straight part 2 of the paper pasted on both sides is attached to the side of the box body. S6. Before, during or at the end of the pressing process of the mold structure, the modular pusher structure set at the corresponding position of the box body bending point pushes the bending part 3 into the box bending point, so that the glued box paper is attached to the bending surface or bending edge under the combined action of the cutting line 4 and the indentation line. S7. Maintain pressure in the mold structure and pusher structure to hold pressure; S8. After the pressure holding period ends, the mold structure and pusher structure are reset in sequence to complete the automatic box gluing.

[0022] By setting several cutting lines 4 along the arc length of the curved portion 3 of the box-making paper, the curved portion 3 is divided into multiple independently deformable bonding pieces. When folding after bending, each bonding piece can adapt to the folding deformation, avoiding wrinkles and curling edges caused by cumulative deformation of the paper during folding, which significantly improves the pasting quality of the curved and folded parts of the irregularly shaped box. Through the automatic pressing of the straight portions 2 on both sides by the first mold 5 and the second mold 6 moving in opposite directions in the box-making machine, and with the modular pusher structure pushing the curved portion 3 in and guiding it to be bonded during the pressing process, the fully automatic pasting of the formed irregularly shaped box from the straight edge to the curved edge is realized without manual intervention, which effectively solves the technical problem of the difficult positioning and bonding of the paper at the curved and folded parts of the irregularly shaped box. At the same time, it can be connected to the continuous production cycle of the box-making machine, which significantly improves the production efficiency, and the consistency of the pasting position is stably maintained through the positioning mechanism and control program.

[0023] In some embodiments, the cutting lines 4 are spaced apart along the arc length of the curved portion 3, dividing the curved portion 3 into multiple independently deformable bonding pieces. The spacing between adjacent cutting lines 4 is determined according to the radius of curvature at the curved part of the box; the smaller the radius of curvature, the smaller the spacing between the cutting lines 4, and the larger the radius of curvature, the larger the spacing between the cutting lines 4. By arranging the cutting lines 4 spaced apart along the arc length of the curved portion 3, the curved portion 3 is divided into multiple independently deformable bonding pieces. Each piece can rotate and shift relative to the others during pressing, thus fitting the curved contour together. At the same time, the spacing between the cutting lines 4 is determined according to the radius of curvature; the smaller the radius of curvature, the smaller the spacing and the more bonding pieces, giving the face paper a higher degree of deformation freedom at the point of severe bending, and the larger the radius of curvature, the larger the spacing and the fewer bonding pieces. This reduces the cutting process and maintains the integrity of the face paper while ensuring bonding quality, achieving the optimal match between deformation capacity and structural strength under different degrees of bending, and further broadening the applicability of the method.

[0024] In some embodiments, the depth of the crease line is 40% to 60% of the thickness of the linerboard. By controlling the crease line depth to 40% to 60% of the linerboard thickness, sufficient bending flexibility is ensured between the straight portion 2 and the curved portion 3, allowing the curved portion 3 to rotate smoothly relative to the straight portion 2 under the action of the pusher and conform to the curved contour. On the other hand, it avoids the linerboard breaking or losing strength at the crease due to excessive crease depth, and also avoids excessive bending resistance and insufficient deformation of the curved portion 3 due to insufficient crease depth, ensuring that the linerboard has both good flexibility and sufficient structural strength during the bending and bonding process.

[0025] In some embodiments, the modular pusher structure includes a pusher base and one or more replaceable pusher blocks mounted on the pusher base, the end faces of which match the curved contour of the box body. Through the modular design of the pusher base and replaceable pusher blocks, the pusher structure can quickly replace pusher blocks of corresponding specifications according to the curved shape of different irregularly shaped boxes. The matching of the pusher block end faces with the curved contour of the box body ensures that each small piece of the face paper can be accurately guided to the predetermined curved surface during push-in, effectively improving the guiding accuracy and bonding quality of the pusher. Simultaneously, the same pusher base can accommodate multiple pusher blocks; during shape change, only the pusher blocks need to be replaced without replacing the entire pusher structure, reducing equipment costs and changeover time. This method and equipment are applicable to various irregularly shaped boxes with different radii, different bending angles, and combinations of straight and curved sections, demonstrating good versatility and industrial practical value.

[0026] In some embodiments, both the first mold 5 and the second mold 6 are provided with straight pressing surfaces for pressing the straight portions 2 of the box-making paper. By providing straight pressing surfaces on the first mold 5 and the second mold 6, the straight portions 2 of the box-making paper can be pressed evenly and smoothly onto the straight side of the box body in a planar contact manner when the molds move towards each other. The straight pressing surfaces provide uniform surface pressure, avoiding problems such as air bubbles, wrinkles, or poor adhesion of the straight portions 2 during the pressing process, and ensuring the pasting quality of the straight edges.

[0027] In some embodiments, the first mold 5 and the second mold 6 are further provided with arc-shaped pressing surfaces at positions corresponding to the bends in the box body, for assisting in pressing or limiting the bends in the box body. By providing arc-shaped pressing surfaces at positions corresponding to the bends in the box body on the first mold 5 and the second mold 6, the mold structure can assist in pressing or limiting the bends in the box body while pressing the straight part 2. After the pusher structure pushes the bend 3 into the guide, the arc-shaped pressing surface can apply further shaping pressure to the bend 3 as the molds move in opposite directions, ensuring that each bonding piece of the bend 3 is fully compacted after deformation by the cutting line 4 and the indentation line, improving the bonding firmness and outline clarity of the bends in the box body. At the same time, the arc-shaped pressing surface can also prevent the bends in the box body from shifting during the pressing process, ensuring the dimensional accuracy of the box.

[0028] In some embodiments, in S6, the pusher structure pushes the curved portion 3 into the box-shaped bend during the mold structure pressing process. By setting the pusher structure's pushing action to occur during the mold structure pressing process, the curved portion 3 is guided and fitted by the pusher while the mold structure continuously provides pressing pressure. The two work together—the pusher is responsible for sequentially guiding each fitted piece of the curved portion 3 into the curved contour, and the mold is responsible for maintaining the overall pressing state and providing reaction force support—achieving continuous operation of the curved portion 3's paper from guiding to shaping. This avoids the problem of the paper springing back after the pusher pushes in first or the pusher being unable to enter after the mold presses in first, optimizing the action sequence and improving the efficiency and reliability of box gluing.

[0029] In some embodiments, in step S2, the adhesive application method is roller coating, spraying, or hot melt adhesive coating. By providing multiple adhesive application methods such as roller coating, spraying, and hot melt adhesive coating, this method allows for flexible selection of the most suitable adhesive application method based on different face paper materials, box materials, and adhesive types. Roller coating is suitable for mass production with precise adhesive control, spraying is suitable for uniform adhesive application on complex-shaped face papers, and hot melt adhesive coating is suitable for rapid curing and high-speed production scenarios. The selection of multiple methods enhances the process adaptability and production flexibility of the method.

[0030] An automatic gluing device for irregularly shaped boxes includes: The box-making machine has a gluing station and a relative lifting mechanism, which is used to lift the longer sides of the gluing paper relative to the box body. The mold structure, set at the box gluing station, includes a first mold 5 and a second mold 6 arranged opposite to each other. The two molds can move towards each other in the direction close to the box body, and are used to press and paste the mounting paper on both sides of the box body to the side of the box body. The modular pusher structure is set at the corresponding position of the box body bend, and is used to push the bent part 3 of the box face paper into the box bend and guide it to be glued.

[0031] By organically combining the box-making machine, mold structure, and modular pusher structure, a complete automated box-gluing equipment solution is formed, encompassing box positioning, relative lifting of the long side of the face paper, pressing of the straight section 2, and pushing and guiding of the curved section 3. The relative arrangement of the mold structure enables synchronous pressing of the straight sections 2 on both sides, improving production efficiency. The modular pusher structure provides directional pushing and guiding for the special needs of the curved and folded parts of irregularly shaped boxes, solving the technical blind spot of existing equipment being unable to handle the face paper bonding at curved and folded parts. The overall structure of the equipment is compatible with this method and can be integrated into existing box-making machine production lines, achieving automatic box gluing of irregularly shaped boxes without large-scale modifications to existing equipment, demonstrating good industrial adaptability and promotional value.

[0032] In some embodiments, the modular pusher structure includes a pusher base and a replaceable pusher block mounted on the pusher base, the end face of which matches the curved contour of the box body. By setting a pusher base and a replaceable pusher block mounted on the pusher base in the equipment, and ensuring that the end face of the pusher block matches the curved contour of the box body, the equipment has a rapid changeover capability. For different irregularly shaped box products, only the corresponding pusher block needs to be replaced before production can begin, without replacing the entire pusher structure or readjusting the equipment. The changeover time is short and the operation is simple. At the same time, the matching design of the pusher block end face and the curved contour ensures the consistency of the guiding accuracy and bonding effect of each push, enabling the equipment to stably output high-quality glued box products in mass production.

[0033] Working principle and process I. Equipment Composition and Working Principle The automatic gluing equipment for irregularly shaped boxes described in this invention comprises three main parts: a top and bottom box machine, a mold structure, and a modular pusher structure.

[0034] The box-making machine is the base of existing automatic box-making equipment, and it is equipped with a box-making station and a relative lifting mechanism. The box-making station provides operating space for positioning and pressing the box body and the face paper. The relative lifting mechanism (such as lifting strips or lifting rollers 7) is used to lift the longer sides of the face paper relative to the box body, so that the longer sides of the face paper are bent upward and attached to the side of the box body.

[0035] The mold structure includes a first mold 5 and a second mold 6 positioned opposite each other on both sides of the box-gluing station, each connected to an independent drive device (such as a cylinder or servo motor). Both the first mold 5 and the second mold 6 have straight pressing surfaces, corresponding to the straight edges of the box body on both sides. When the drive device is activated, the first mold 5 and the second mold 6 move towards each other in the horizontal direction, and the straight pressing surfaces press from both sides towards the center, evenly pressing and attaching the straight portion 2 of the box-gluing paper to the straight edge side of the box body. Furthermore, at positions corresponding to the curved parts of the box body, the first mold 5 and the second mold 6 also have arc-shaped pressing surfaces, which can assist in limiting and shaping the curved and folded areas while pressing the straight portion 2.

[0036] The modular pusher structure includes a pusher base and a replaceable pusher block mounted on the pusher base. The pusher base is fixedly mounted on the frame of the box-top box machine, located on the outer side of the corresponding bending and folding part of the box body. The pusher block is mounted on the pusher base via a quick-connect structure (such as a threaded connection or quick-release buckle), and its end face shape matches the bending contour of the box body. The pusher block is connected to an independent drive device (such as a cylinder), which can reciprocate in a predetermined direction under the command of the control system, pushing the bent part 3 from the outside towards the bending surface of the box body.

[0037] The timing of each actuator is coordinated by the control system. The control system detects the position and status of each actuator through sensors and issues action commands according to the preset timing logic to ensure that the mold structure and the pusher structure work together in sequence to complete the automatic box gluing.

[0038] II. Work Process The working process of the automatic gluing method for irregularly shaped boxes described in this invention includes the following steps: Step S1: Prepare the box-making liner. Design and die-cut the box-making liner according to the unfolded outline of the pre-formed irregular box. The box-making liner includes a central bottom-attaching area 1, straight sections 2 located on both sides of the central bottom-attaching area 1, and curved sections 3 corresponding to the curved parts of the box body. Indentation lines are set between the straight sections 2 and the curved sections 3, with an indentation depth of 40%~60% of the liner thickness. Several cutting lines 4 are spaced along the arc length of the curved sections 3. The spacing of the cutting lines 4 is determined according to the radius of curvature of the curved part of the box body: the smaller the radius of curvature, the smaller the spacing of the cutting lines 4; the larger the radius of curvature, the larger the spacing of the cutting lines 4. The cutting lines 4 divide the curved sections 3 into multiple independently deformable bonding pieces. Each bonding piece maintains a basically planar shape in its natural state, but when pushed, it can rotate independently around the indentation lines and undergo slight misalignment along the arc length, thus conforming to the curved outline for bonding.

[0039] Step S2: Apply glue to the face paper. Use roller coating, spraying, or hot melt adhesive application to evenly apply glue to the back of the face paper (i.e., the side that contacts the box body). The glued area covers the center bottom area 1, the straight section 2, and the curved section 3. The amount of glue applied is controlled within a predetermined range according to the type of glue and the face paper material.

[0040] Step S3: Positioning the box body and the facing paper. The pre-formed box body and the glued facing paper are fed into the gluing station via the conveyor mechanism of the box-making machine. A positioning mechanism aligns the center bottom-attaching area 1 of the facing paper with the bottom surface of the box body, the straight section 2 with the straight edge of the box body, and the curved section 3 with the curved fold of the box body. Positioning accuracy is confirmed by sensors to ensure accurate correspondence between each area and the corresponding part of the box body.

[0041] Step S4: Lift the longer sides of the box linerboard relative to each other. The box body is attracted and lowered by the robotic arm. After the longer sides of the box linerboard come into contact with the relative lifting mechanism (such as the lifting strip or lifting roller 7), they are lifted relative to each other and bent upward. As the box body continues to descend, the longer sides of the linerboard adhere to the two sides of the box body.

[0042] Step S5: The molds move towards each other to press the straight section 2. The control system sends commands to the drive devices of the first mold 5 and the second mold 6, driving them to move towards each other at a uniform speed along the direction close to the box body. When the straight pressing surface of the mold contacts the straight section 2 of the glued box face paper, a predetermined pressure (generally 0.3~0.5MPa) is continuously applied to press and attach the straight sections 2 of the glued face paper on both sides to the straight side of the box body. During the pressing process, the straight pressing surface provides uniform surface pressure, squeezing out air bubbles and excess glue from the bonding interface, ensuring that the straight section 2 is flatly bonded to the side of the box body.

[0043] Step S6: The pusher structure pushes into the curved section 3. Before, during, or at the end of the pressing process (preferably during pressing), the control system sends a command to the drive device of the modular pusher structure. The pusher block advances from the outside to the inside of the curved section of the box. The end face of the pusher block presses each of the bonding pieces of the curved section 3 sequentially onto the curved surface of the box along the curved contour. During the pushing process, each bonding piece rotates relative to the other and moves slightly at the cutting line 4, conforming to the curved contour. When folding after bending, since the face paper is segmented independently at the cutting line, each bonding piece can adapt to the folding deformation separately, avoiding wrinkles caused by cumulative deformation of the face paper during the folding process.

[0044] It should be noted that steps S5 and S6 are not strictly sequential; the preferred sequence is for the pusher structure to push the curved portion 3 into place during the mold pressing process. At this time, the arc-shaped pressing surface of the mold structure provides reaction force support to the curved and folded part of the box, and the pusher block pushes the curved portion 3 towards the arc-shaped pressing surface from the outside. The two work together to ensure that the paper of the curved portion 3 is fully compacted under the limiting and reaction force of the arc-shaped pressing surface, ensuring that the curved portion 3 is completely adhered to the curved surface of the box.

[0045] Step S7, Pressure Holding and Curing. After the pusher structure is in place, the mold structure and pusher structure maintain pressure for a predetermined time (determined according to the type of adhesive: 30-60 seconds for water-based white glue, 5-15 seconds for hot melt adhesive) to fully wet the face paper and box surface and preliminarily cure the adhesive, ensuring that the bonding strength of the straight part 2 and the curved part 3 meets the predetermined requirements.

[0046] Step S8: Reset Complete. After the pressure holding period, the control system issues a reset command in the order of first pushing the die and then the mold. The pushing die first returns to its initial position, followed by the first mold 5 and the second mold 6. The finished shaped box is conveyed out of the gluing station by the conveyor belt and enters the next process.

[0047] The core principle of this invention lies in the design of the cutting line 4 of the curved section 3 of the face paper, which transforms the continuous face paper into multiple independently deformable bonding pieces. This transforms the difficult problem of "continuous curved surface bonding" into an easily achievable method of "sequential bonding of multiple small planes / narrow strips". When folding after bending, each bonding piece can adapt to the folding deformation, avoiding wrinkles caused by cumulative deformation of the face paper during the folding process. Through the timing coordination of the mold structure and the pusher structure, the pressing of the straight edge and the guiding push of the curved folding part are completed sequentially or collaboratively in the same station. By matching the shape of the end face of the pusher block with the curved contour, the face paper of the curved section 3 is accurately guided and positioned, thereby realizing fully automatic and high-quality gluing of pre-formed irregular boxes on the box gluing machine platform.

[0048] Example 1

[0049] This embodiment uses an irregularly shaped box with rounded corners as an example to illustrate the working process of the automatic box-gluing method and equipment of the present invention.

[0050] Preparation of box-making paper The box linerboard is made through die-cutting and creasing processes. The box linerboard includes a central bottom-attached area 1, straight sections 2 located on both sides of the central bottom-attached area 1, and curved sections 3 corresponding to the curves of the box body.

[0051] An indentation line is provided between the straight section 2 and the curved section 3. The depth of the indentation line is 50% of the thickness of the face paper, which facilitates the bending of the curved section 3 relative to the straight section 2. The curved section 3 is provided with several cutting lines 4 spaced apart along the arc length direction, dividing the curved section 3 into multiple independently deformable bonding pieces. In this embodiment, the radius of curvature at the curved part of the box is 15mm, and the spacing between adjacent cutting lines 4 is 5mm. Each bonding piece maintains a planar shape in its natural state, but when pushed, it can rotate independently around the indentation line and undergo slight misalignment along the arc length direction, thereby conforming to the curved contour.

[0052] The box linerboard is made of 250g / m² white cardboard, and decorative patterns can be pre-printed on the surface.

[0053] Automatic box gluing equipment The automatic box-gluing structure is installed in the box-gluing machine. The automatic box-gluing structure includes a mold structure and a modular pusher structure.

[0054] The mold structure includes a first mold 5 and a second mold 6 arranged opposite to each other, which can move towards each other in the direction close to the box body. Both the first mold 5 and the second mold 6 are provided with straight pressing surfaces for pressing the straight portion 2 of the box cover paper. In addition, at the position corresponding to the bending and folding part of the box body, the first mold 5 and the second mold 6 are also provided with arc-shaped pressing surfaces to assist in pressing or limit the bending and folding part of the box body.

[0055] The modular pusher structure is positioned at the corresponding location of the box body's bend and fold, including a pusher seat and a replaceable pusher block mounted on the pusher seat. The end face of the pusher block matches the bend profile of the box body and is used to push the bend 3 into the bend of the box shape, so that the face paper adheres to the bend surface or bend edge under the combined action of the cutting line 4 and the creasing line.

[0056] Box gluing process The specific steps for gluing the box are as follows: (1) Apply glue to the back of the die-cut and creasing box paper by roller coating. The glue is water-based white latex, and the amount of glue applied is 8g / m²~12g / m².

[0057] (2) Position the formed box body and the gluing paper in the gluing station of the box-making machine, so that the center bottom-attached area 1 of the gluing paper corresponds to the bottom surface of the box body, the straight part 2 corresponds to the straight edge of the box body, and the curved part 3 corresponds to the curved and folded part of the box body.

[0058] (3) The box is attracted and lowered by the robot arm. The longer sides of the box cover paper are lifted and bent upward after contacting the relative lifting mechanism. As the box continues to descend, the longer sides of the cover paper adhere to the two sides of the box.

[0059] (4) Drive the first mold 5 structure and the second mold 6 structure to move towards each other in the direction close to the box body, so that the straight part 2 of the paper pasted on both sides is attached to the side of the box body. The pressure of the straight pressing surface is 0.3MPa~0.5MPa.

[0060] (5) During the pressing process of the mold structure, the pusher block of the modular pusher structure is pushed from the outside to the inside of the bending and folding part, pushing the bending part 3 into the box-shaped bending part. The pushing speed of the pusher block is 20mm / s~30mm / s, and the pushing stroke is determined according to the depth of the bending part of the box. During the pushing process of the pusher block, the small pieces of the bending part 3 undergo relative rotation and slight misalignment at the cutting line 4, conforming to the bending contour and effectively avoiding wrinkles and curling edges when the face paper is folded after bending.

[0061] (6) Maintain pressure on the mold structure and pusher structure for 30 to 60 seconds to allow the glue to fully cure.

[0062] (7) After the pressure holding is completed, the pusher block is reset first, and then the first mold 5 structure and the second mold 6 structure are reset to complete the automatic box gluing.

[0063] The method of this embodiment is used to glue rounded corner irregular box. The surface of the curved and folded part is flat without wrinkles or curling edges. The transition between the straight part 2 and the curved part 3 is natural. The single gluing cycle is about 45 seconds, which is significantly more efficient than manual gluing (about 120 seconds / piece).

[0064] Example 2

[0065] This embodiment uses an irregularly shaped box with a convex arc edge as an example to illustrate the automatic box-gluing method of the present invention.

[0066] Unlike Embodiment 1, in this embodiment, the curved part of the box body has an outwardly convex arc edge with a radius of curvature of 25mm. Correspondingly, the spacing of the cutting lines 4 along the arc length direction of the curved portion 3 of the box liner is 8mm. Since the curvature of the outwardly convex arc edge is relatively gentle, the spacing of the cutting lines 4 can be appropriately increased to reduce the number of small pieces to be bonded and simplify the liner preparation process. The depth of the crease line is 45% of the liner thickness, and the adhesive is applied by spraying with an adhesive amount of 10g / m²~14g / m².

[0067] The end face shape of the pusher block in the modular pusher structure matches the convex arc contour. During push-in, the pusher block advances from the outside to the inside of the arc edge, pressing the various fitting pieces of the curved part 3 onto the arc surface in sequence.

[0068] In this embodiment, the pusher structure begins to advance before the mold structure presses together. That is, before the mold structure contacts the straight portion 2 of the face paper, the pusher block first pushes the curved portion 3 into position, so that the curved portion 3 is initially positioned at the bend and fold. Subsequently, the mold structure moves towards each other to press the straight portion 2 together, while the pusher block continues to advance to completely press each bonding piece onto the convex arc surface. The advancing speed of the pusher block is 15mm / s to 25mm / s, and the holding time is 40 seconds.

[0069] The remaining steps are the same as in Example 1. With this parameter configuration, the paper adhesion rate of the convex arc edge reaches over 98%, with no wrinkling or curling. By advancing the pusher action to before the mold pressing, the bent part 3 can be positioned in advance, which is especially suitable for box types with a large convex arc (radius of curvature greater than 20mm), and the bent part 3 is less likely to shift during the mold pressing process.

[0070] Example 3

[0071] This embodiment uses an irregularly shaped box with a concave arc edge as an example to illustrate the automatic box-gluing method of the present invention.

[0072] Unlike Embodiment 1, in this embodiment, the curved part of the box body has an inwardly concave arc edge with a radius of curvature of 10mm. The curvature of the inwardly concave arc edge is more pronounced, and the spacing of the cutting lines 4 along the arc length direction of the curved part 3 of the box liner is 3mm, which is smaller than the spacing of the cutting lines 4 in Embodiments 1 and 2, to ensure that the curved part 3 has sufficient deformation capacity to conform to the concave contour and fit tightly. The depth of the crease line is 55% of the thickness of the liner.

[0073] The end face shape of the pusher block in the modular pusher structure matches the concave arc contour. During insertion, the pusher block advances from the outside to the inside of the concave arc edge, sequentially pressing each of the bonding pieces of the curved portion 3 onto the concave surface. In this embodiment, due to the small radius of curvature and large degree of curvature of the concave arc edge, the pushing speed of the pusher block is set to 10mm / s~20mm / s, which is slower than in Embodiments 1 and 2, to ensure that each bonding piece has sufficient time to deform and bond in place.

[0074] In this embodiment, the pusher structure begins to advance at the end of the mold structure pressing process. That is, after the straight pressing surface of the mold structure presses the straight part 2 into place, the pusher block then begins to advance to press the curved part 3 into the concave arc surface. At this time, the arc pressing surface of the mold structure is close to and limits the bending and folding part of the box body, providing reliable reaction force support for the advancement of the pusher block.

[0075] The remaining steps are the same as in Example 1. With this parameter configuration, the face paper with the concave arc edge is tightly bonded without air bubbles, the edges are not raised, and the gap between the cutting lines 4 of each bonded piece is controlled within 0.3mm, which does not affect the appearance.

[0076] Example 4

[0077] This embodiment uses an irregularly shaped box with multiple bends of different radii of curvature as an example to illustrate the correspondence between the spacing of the box-covering paper cutting line 4 and the radius of curvature.

[0078] In this embodiment, the irregularly shaped box has multiple bends with different radii of curvature: the first bend has a radius of curvature of 8mm, the second bend has a radius of curvature of 12mm, and the third bend has a radius of curvature of 20mm.

[0079] The spacing of cutting lines 4 is set according to different radii of curvature: First bend (radius of curvature 8mm): Cutting line 4, spacing 3mm Second bend (radius of curvature 12mm): Cutting line 4, spacing 5mm At the third bend (radius of curvature 20mm): Cutting line 4 with a spacing of 7mm. The depth of the indentation lines at each bend is set to 50% of the thickness of the face paper. Hot melt adhesive is applied uniformly, with an application amount of 6g / m² to 10g / m². The hot melt adhesive cures quickly, and the pressure holding time is only 8 to 12 seconds.

[0080] Multiple modular pusher structures are positioned at corresponding locations at each bend and fold, with the end face of each pusher block matching its corresponding bend profile. The pusher actions are independently controlled by the control system, with each pusher block having its own set advance speed and stroke based on its own bend radius and position, without interference between them.

[0081] The remaining steps are the same as in Example 1. This example demonstrates that the present invention can flexibly adjust the spacing of the cutting lines 4 according to the radius of curvature at different bends in the box, and uses multiple independently controlled modular pusher structures to process each bend and fold separately. It is suitable for complex irregular-shaped boxes with multiple different bending radii and has good process adaptability.

[0082] Example 5

[0083] This embodiment uses an irregularly shaped box with a continuous transition between straight and curved sections as an example to illustrate the shape change operation of the automatic box gluing equipment of the present invention.

[0084] In this embodiment, the irregularly shaped box has a complex contour with a continuous transition from "straight line segment - convex arc segment - straight line segment - concave arc segment". The box cover paper is provided with multiple curved sections 3 and multiple straight sections 2. Each curved section 3 has a cutting line 4 spacing set according to its own radius of curvature (18mm radius of curvature for convex arc segment, 6mm spacing; 12mm radius of curvature for concave arc segment, 4mm spacing). Indentation lines are provided between each straight section 2 and curved section 3.

[0085] During equipment changeover, operators remove the existing pusher blocks from the pusher holder, select the corresponding pusher blocks based on the new box's curved contour, and install them on the pusher holder, ensuring the pusher block end faces match the contours of each bend and fold in the new box. Simultaneously, the stroke limits of the first mold 5 and the second mold 6 are adjusted according to the dimensions of the new box, ensuring the pressing position of the straight pressing surface corresponds to the straight edge of the box. If the radius of curvature at the bend in the box changes significantly, a mold structure with a corresponding arc-shaped pressing surface must be replaced. After the changeover is complete, test box assembly confirms all parameters, and mass production can begin.

[0086] This embodiment demonstrates that the present invention, through its modular pusher structure and replaceable mold structure, enables rapid changeover between different irregularly shaped boxes. The changeover time can be controlled within 15 to 30 minutes, which is significantly better than the changeover efficiency of the traditional manual box gluing method. It is suitable for the production of irregularly shaped boxes in a variety of products and small batches.

[0087] The remaining steps are the same as in Example 1.

[0088] The above descriptions are merely some embodiments of the present invention. For those skilled in the art, various modifications and improvements can be made without departing from the inventive concept of the present invention, and these all fall within the protection scope of the present invention.

Claims

1. An automatic gluing method for irregularly shaped boxes, characterized in that, The irregularly shaped box has at least two parallel sides, and the method includes the following steps: S1. Prepare a box-making paper according to the unfolded outline of the pre-formed irregular box. The box-making paper includes a central bottom-fitting area, straight sections on both sides of the central bottom-fitting area, and curved sections corresponding to the curved parts of the box body. An indentation line is provided between the straight sections and the curved sections. Several cutting lines are provided along the arc length direction of the curved sections so that the curved sections can deform in segments and conform to the curved outline of the box body when pushed. S2. Apply adhesive to the paper used for gluing the box; S3. Position the formed box body and the gluing paper in the gluing station of the top and bottom box machine; S4. The relative lifting mechanism of the box-making machine lifts the longer sides of the glued box paper relative to the box body. S5. Drive the first and second molds, which are set opposite to each other, to move towards each other in the direction close to the box body, so that the straight part of the paper pasted on both sides is attached to the side of the box body. S6. Before, during or at the end of the pressing process of the mold structure, the modular pusher structure set at the corresponding position of the box body bend pushes the bent part into the box bend, so that the glued paper is attached to the bent surface or the bent edge under the combined action of the cutting line and the indentation line. S7. Maintain pressure in the mold structure and pusher structure to hold pressure; S8. After the pressure holding period ends, the mold structure and pusher structure are reset in sequence to complete the automatic box gluing.

2. The automatic gluing method for irregularly shaped boxes according to claim 1, characterized in that, The cutting lines are arranged at intervals along the arc length of the curved part, cutting the curved part into multiple independently deformable fitting pieces; the spacing between adjacent cutting lines is determined according to the radius of curvature of the curved part of the box. The smaller the radius of curvature, the smaller the spacing between cutting lines, and the larger the radius of curvature, the larger the spacing between cutting lines.

3. The automatic gluing method for irregularly shaped boxes according to claim 1, characterized in that, The depth of the crease line is 40% to 60% of the thickness of the box-making paper.

4. The automatic gluing method for irregularly shaped boxes according to claim 1, characterized in that, The modular pusher structure includes a pusher base and one or more replaceable pusher blocks mounted on the pusher base, the end face of which matches the curved profile of the housing.

5. The automatic gluing method for irregularly shaped boxes according to claim 1, characterized in that, Both the first mold and the second mold are provided with straight pressing surfaces for pressing the straight parts of the glue box paper.

6. The automatic gluing method for irregularly shaped boxes according to claim 1, characterized in that, The first mold and the second mold are also provided with arc-shaped pressing surfaces at the positions corresponding to the bending points of the box body, which are used to assist in pressing or limit the bending points of the box body.

7. The automatic gluing method for irregularly shaped boxes according to claim 1, characterized in that, In step S6, the pusher structure pushes the curved part into the box-shaped curved part during the mold structure pressing process.

8. The automatic gluing method for irregularly shaped boxes according to claim 1, characterized in that, In S2, the adhesive application method is roller coating, spraying, or hot melt adhesive coating.

9. An automatic gluing device for irregularly shaped boxes for implementing the method as described in any one of claims 1-8, characterized in that, include: The box-making machine has a gluing station and a relative lifting mechanism, which is used to lift the longer sides of the gluing paper relative to the box body. The mold structure, set at the box gluing station, includes a first mold and a second mold arranged opposite to each other, which can move towards each other in the direction close to the box body, and are used to press and paste the mounting paper on both sides of the box body to the side of the box body. The modular pusher structure is set at the corresponding position of the box body bend, and is used to push the curved part of the box face paper into the box bend and guide it to be glued.

10. The automatic gluing equipment for irregularly shaped boxes according to claim 9, characterized in that: The modular pusher structure includes a pusher base and a replaceable pusher block mounted on the pusher base, the end face of which matches the curved profile of the box body.

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