Combined paperboard packaging box and forming method thereof
The modular cardboard packaging box, which is formed by die-cutting a single sheet of cardboard, adopts a multi-layer pressing design with plug-socket interlocking, inner flaps, and pressure plates. This solves the problems of long production cycles and easy damage during transportation, and achieves the effects of cost reduction and structural stability.
Patent Information
- Application Number
- CN202511375490.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-25
- Publication Date
- 2025-11-21
AI Technical Summary
Existing modular cardboard packaging boxes have long production cycles and high costs, and the boxes take up a lot of space and are easily damaged during transportation.
The outer box and the inner tray of the floor box are formed by die-cutting from a single sheet of cardboard and have a flat folding structure. The plug-socket interlocking and the multi-layer pressing design of the inner flap and pressure plate form a self-locking structure that does not require glue. Both the inner tray and the outer box are transported in a flat folded state.
It simplifies the production process, reduces production costs, decreases the types of materials and the number of parts, reduces the space occupied during transportation and the risk of damage, and improves the stability and load-bearing capacity of the structure.
Smart Images
Figure CN120986808A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of packaging boxes, and more specifically, to a modular cardboard packaging box and a method for forming the same. Background Technology
[0002] Modular packaging boxes are widely used for packaging high-end gifts, luxury goods, electronic products, and precision instruments due to their ingenious structure, strong decorative appeal, and ability to provide a good sense of layering and protection. These boxes typically consist of two parts: an independent outer box with a flat folding structure and an inner tray. The inner tray is fixed to the outer box's flat folding structure, which folds to close the inner tray.
[0003] In related technologies, the outer box's planar folding structure is typically composed of two parts bonded together: a decorative liner and a supporting gray board. The manufacturing process begins by die-cutting the liner into a semi-finished form according to the design drawings. Simultaneously, the gray board is die-cut to obtain a flat, unfolded material. Then, through precise die-cutting or grooving processes, indentations and grooves for bending are created on the gray board. Finally, the die-cut liner and the formed gray board are manually glued and bonded, then pressed and shaped in a mold to obtain the final outer box's planar folding structure. The inner box tray is typically composed of a gray board sheet with a "well"-shaped structure bonded to the decorative liner. Adhesive strips are provided on both sides of the gray board sheet. The gray board sheet needs to be upright along the pre-set indentations on all four sides. The adhesive strips are then folded inwards, glued, and attached to the upright sides for shaping.
[0004] Using the above technical solution, both the outer box's flat folding structure and the inner tray of the floor box are bonded and pressed using grey board and face paper, resulting in a long production cycle, difficult assembly, and high costs. Furthermore, the floor box requires adhesive bonding to form a three-dimensional shape, which occupies a significant amount of transport space and is easily damaged during transportation.
[0005] Therefore, the industry urgently needs a new modular cardboard packaging box structure and its manufacturing method that can simplify production steps, reduce production costs, and facilitate transportation. Summary of the Invention
[0006] To address the aforementioned technical issues, this application provides a modular cardboard packaging box and its forming method, which simplifies production steps, reduces production costs, and facilitates transportation.
[0007] In the first aspect, this application provides a modular cardboard packaging box, which adopts the following technical solution:
[0008] A combined paperboard packaging box, comprising an outer box plane folding structure and a ground box inner support plane folding structure, the outer box plane folding structure and the ground box inner support plane folding structure are both formed by a single paperboard, the ground box inner support plane folding structure comprises a rectangular bottom plate, a left side plate and a right side plate respectively formed on left and right sides of the rectangular bottom plate, a front side plate and a back side plate respectively formed on front and back sides of the rectangular bottom plate, the front side plate is provided with a first left connecting ear connected with the left side plate and a first right connecting ear connected with the right side plate on left and right sides thereof respectively, the back side plate is provided with a second left connecting ear connected with the left side plate and a second right connecting ear connected with the right side plate on left and right sides thereof respectively, the front side plate is provided with a front inner turning plate on a side away from the rectangular bottom plate, the back side plate is provided with a back inner turning plate on a side away from the rectangular bottom plate, the left side plate is provided with a left inner turning plate on a side away from the rectangular bottom plate, the right side plate is provided with a right inner turning plate on a side away from the rectangular bottom plate, the left side plate and the right side plate are both provided with plugs on front and back sides thereof, the left side plate and the right side plate are both provided with two insertion holes, the two insertion holes are respectively used for inserting the plug of the left side plate and the plug of the right side plate, the outer box plane folding structure comprises a bottom support plate, a left side cover plate, an upper cover plate and a right side cover plate which are sequentially arranged, and the rectangular bottom plate is bonded to the bottom support plate.
[0009] Preferably, a first straight line V groove is die-cut and formed at a connection between the left side plate and the rectangular bottom plate, the first straight line V groove extends along a length direction of a left side of the rectangular bottom plate, a second straight line V groove is die-cut and formed at a connection between the right side plate and the rectangular bottom plate, the second straight line V groove extends along a length direction of a right side of the rectangular bottom plate, a third straight line V groove is die-cut and formed at a connection between the front side plate and the rectangular bottom plate, the third straight line V groove extends along a length direction of a front side of the rectangular bottom plate, and a fourth straight line V groove is die-cut and formed at a connection between the back side plate and the rectangular bottom plate, the fourth straight line V groove extends along a length direction of a back side of the rectangular bottom plate.
[0010] Preferably, the left side plate is die-cut and formed with two fifth straight-line V grooves parallel and spaced apart away from one side of the rectangular base plate, the two fifth straight-line V grooves extend along the length direction of the left side edge of the rectangular base plate, and one of the fifth straight-line V grooves is located at the connection between the left side plate and the left varus plate, and a left top plate is formed between the two fifth straight-line V grooves, the right side plate is die-cut and formed with two sixth straight-line V grooves parallel and spaced apart away from one side of the rectangular base plate, the two sixth straight-line V grooves extend along the length direction of the right side edge of the rectangular base plate, and one of the sixth straight-line V grooves is located at the connection between the right side plate and the right varus plate, and a right top plate is formed between the two sixth straight-line V grooves, the front side plate is die-cut and formed with two seventh straight-line V grooves parallel and spaced apart away from one side of the rectangular base plate, the two seventh straight-line V grooves extend along the length direction of the front side edge of the rectangular base plate, and one of the seventh straight-line V grooves is located at the connection between the front side plate and the front varus plate, and a front top plate is formed between the two seventh straight-line V grooves, and the rear side plate is die-cut and formed with two eighth straight-line V grooves parallel and spaced apart away from one side of the rectangular base plate, the two eighth straight-line V grooves extend along the length direction of the rear side edge of the rectangular base plate, and one of the eighth straight-line V grooves is located at the connection between the rear side plate and the rear varus plate, and a rear top plate is formed between the two eighth straight-line V grooves.
[0011] Preferably, the left varus plate is provided with a left inner folding plate away from one side of the left side plate, and a ninth straight-line V groove extending along the length direction of the left side edge of the rectangular base plate is die-cut and formed at the connection between the left inner folding plate and the left varus plate, and the right varus plate is provided with a right inner folding plate away from one side of the left side plate, and a tenth straight-line V groove extending along the length direction of the right side edge of the rectangular base plate is die-cut and formed at the connection between the right inner folding plate and the right varus plate.
[0012] Preferably, a first opening is provided between the left inner folding plate and the left varus plate, and a second opening is provided between the right inner folding plate and the right varus plate.
[0013] Preferably, the front inward turning plate is provided with a first left pressure receiving plate and a first right pressure receiving plate on the left and right sides respectively, the first left pressure receiving plate is die cut and formed with a tenth straight line V groove extending along the length direction of the left side edge of the rectangular bottom plate at the connection with the front inward turning plate, the first right pressure receiving plate is die cut and formed with a twelfth straight line V groove extending along the length direction of the right side edge of the rectangular bottom plate at the connection with the front inward turning plate, the rear inward turning plate is provided with a second left pressure receiving plate and a second right pressure receiving plate on the left and right sides respectively, the second left pressure receiving plate is die cut and formed with a thirteenth straight line V groove extending along the length direction of the left side edge of the rectangular bottom plate at the connection with the rear inward turning plate, and the second right pressure receiving plate is die cut and formed with a fourteenth straight line V groove extending along the length direction of the right side edge of the rectangular bottom plate at the connection with the rear inward turning plate.
[0014] Preferably, the bottom support plate comprises a first body plate, a first thickened folded plate provided on the side of the first body plate away from the left side cover plate, and two second thickened folded plates provided on the opposite sides of the first body plate, the first thickened folded plate and the two second thickened folded plates are folded and glued to and cover the same side of the first body plate, the left side cover plate comprises a second body plate and two third thickened folded plates provided on the opposite sides of the second body plate, the two third thickened folded plates are folded and glued to and cover the same side of the second body plate, the upper side cover plate comprises a third body plate and two fourth thickened folded plates provided on the opposite sides of the third body plate, the two fourth thickened folded plates are folded and glued to and cover the same side of the third body plate, and the right side cover plate comprises a fourth body plate, a fifth thickened folded plate provided on the side of the fourth body plate away from the upper side cover plate, and two sixth thickened folded plates provided on the opposite sides of the fourth body plate, the fifth thickened folded plate and the two sixth thickened folded plates are folded and glued to and cover the same side of the fourth body plate.
[0015] Preferably, the right side cover plate is provided with an insertion plate, and a gap is provided between the bottom support plate and the rectangular bottom plate for the insertion of the insertion plate.
[0016] Preferably, the connection between the first body plate and the second body plate is press-formed with a first score line, the connection between the second body plate and the third body plate is press-formed with a second score line, the connection between the third body plate and the fourth body plate is press-formed with a third score line, the connection between the first thickened folded plate and the two second thickened folded plates and the first body plate is press-formed with a fourth score line, the connection between the two third thickened folded plates and the second body plate is press-formed with a fifth score line, the connection between the two fourth thickened folded plates and the third body plate is press-formed with a sixth score line, and the connection between the fifth thickened folded plate and the two sixth thickened folded plates and the first body plate is press-formed with a seventh score line.
[0017] In a second aspect, the application provides a forming method of a combined paperboard packaging box, which adopts the following technical scheme: a forming method of a combined paperboard packaging box, comprising the following steps: step S1, die cutting an inner box blank: using a die cutting process to process the overall profile of the inner box plane folding structure, all connecting ears, inner folded plates, inner folding plates, pressure plates, plugs, sockets and straight line V grooves forming all creases on a single sheet of paper at one time;
[0018] Step S2, folding and forming the inner box: folding the left side plate, the right side plate, the front side plate and the rear side plate upward along the straight line V groove connecting the rectangular bottom plate of the die-cut inner box plane folding structure, so that the four side plates stand upright; placing the first left connecting ear and the first right connecting ear on the front side plate on the inner side of the left side plate and the right side plate respectively; placing the second left connecting ear and the second right connecting ear on the rear side plate on the inner side of the left side plate and the right side plate respectively; first, folding the left inner folding plate on the left inner folded plate and the right inner folding plate on the right inner folded plate inward; then, folding the front inner folded plate and the rear inner folded plate inward, so that they cover and press the connecting ears on the front side plate and the rear side plate; then, folding the left inner folded plate and the right inner folded plate inward, so that they cover and press the connecting ears on the left side plate and the right side plate, the pressure plates extending out of the front inner folded plate and the rear inner folded plate, and the folded left inner folding plate and the right inner folding plate; finally, inserting the plugs on the front and rear sides of the left side plate into the corresponding sockets on the right side plate, and inserting the plugs on the front and rear sides of the right side plate into the corresponding sockets on the left side plate, to realize the glue-free self-locking fixation of the inner box;
[0019] Step S3, die cutting an outer box blank: using a die cutting process to process the overall profile of the outer box plane folding structure, all thickened folded plates, plug plates and score lines forming creases on another single sheet of paper at one time;
[0020] Step S4, thickening the adhesive outer box wall plate: fold the first thickening fold plate and the two second thickening fold plates on the bottom support plate, and paste them on the same side of the first body plate using glue; fold the two third thickening fold plates on the left side cover plate, and paste them on the same side of the second body plate using glue; fold the two fourth thickening fold plates on the upper cover plate, and paste them on the same side of the third body plate using glue; fold the fifth thickening fold plate and the two sixth thickening fold plates on the right side cover plate, and paste them on the same side of the fourth body plate using glue;
[0021] Step S5, combining the inner box with the outer box: apply glue to the bottom surface of the rectangular bottom plate of the inner box formed in step S2, and paste and fix it to the upper surface of the bottom support plate processed in step S4;
[0022] Step S6, closing the packaging box: fold the left side cover plate upwards to make the left side cover plate fit the left side plate of the inner box, fold the upper cover plate to make the upper cover plate cover the top surface of the inner box, fold the right side cover plate downwards to make the right side cover plate fit the right side plate of the inner box, and finally insert the plug plate on the right side cover plate into the gap between the bottom support plate and the rectangular bottom plate that has been pasted, to complete the closure of the packaging box.
[0023] The present application includes at least one of the following beneficial technical effects:
[0024] 1. The outer box flat folding structure and the inner box are integrally die-cut and formed from a single sheet of paper, abandoning the complex structure of separately processing and bonding the face paper and the gray board in the traditional process, reducing the number of material types and parts, and reducing material costs and management complexity; The inner box is designed with multiple layers of pressure combined through plug-jack interlocking structure, inner turning plate and pressure plate, and can be firmly self-locked after folding, without the need for glue bonding, which not only simplifies the assembly process, but also avoids the process instability and environmental pollution caused by glue; The inner box and the outer box are transported and stored in a flat folding state, which greatly reduces the occupied space and is not easy to be damaged, reducing the logistics cost and the risk of damage.
[0025] 2. The inner box is designed with multiple layers of pressure combined through connecting ears, inner turning plates and pressure plates, and plug interlocking, forming a stable support structure, which significantly improves the bearing and compression resistance.
[0026] 3. The bottom support plate, side cover plate and other parts of the outer box are designed with thickening fold plates, which enhance the thickness and rigidity of the outer box wall plate, making the whole more solid and durable. BRIEF DESCRIPTION OF DRAWINGS
[0027] Figure 1 Figure 1 is a schematic diagram of the flat folding structure of the outer box and the flat folding structure of the inner box of Example 1.
[0028] Figure 2Fig. 1 is a schematic diagram of the overall structure of a combined carton packaging box according to an embodiment of the present application.
[0029] Figure 3 Fig. 2 is a schematic diagram of the inner tray plane folding structure of the base box according to an embodiment of the present application.
[0030] Figure 4 Fig. 3 is a first schematic diagram of the outer box plane folding structure according to an embodiment of the present application.
[0031] Figure 5 Fig. 4 is a schematic diagram of the unfolded structure of the outer box plane folding structure according to an embodiment of the present application. Figure 4
[0032] Fig. 5 is a second schematic diagram of the outer box plane folding structure according to an embodiment of the present application. Figure 6
[0033] Fig. 6 is a schematic diagram of the unfolded structure of the outer box plane folding structure according to an embodiment of the present application. Figure 7 Figure 6 Fig. 7 is a schematic diagram of the overall structure of a combined carton packaging box according to an embodiment of the present application.
[0034] Figure 8 Fig. 8 is a schematic diagram of the inner tray plane folding structure of the base box according to an embodiment of the present application.
[0035] Fig. 9 is a schematic diagram of the unfolded structure of the inner tray plane folding structure according to an embodiment of the present application. DETAILED DESCRIPTION
[0036] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative work are within the protection scope of the present application.
[0037] Embodiment 1
[0038] With reference to Figures 1-3 A combined cardboard packaging box is composed of an outer box flat folding structure 100 and an inner tray flat folding structure 200 of a ground box, both of which are integrally formed by a single piece of cardboard through die cutting and creasing processes, greatly simplifying the production process. The inner tray flat folding structure 200 of the ground box takes a rectangular bottom plate 1 as the core basis. The left side edge of the rectangular bottom plate 1 is connected to the left side plate 3 through a first straight V groove 2 formed by die cutting, the right side edge is connected to the right side plate 5 through a second straight V groove 4, the front side edge is connected to the front side plate 7 through a third straight V groove 6, and the back side edge is connected to the back side plate 9 through a fourth straight V groove 8. These V grooves ensure that each side plate can be precisely bent upward and stand straight. In order to form a stable ground box body structure, the left and right side edges of the front side plate 7 respectively extend out a first left connecting ear 10 and a first right connecting ear, and the left and right side edges of the back side plate 9 respectively extend out a second left connecting ear 1211 and a second right connecting ear 13. These connecting ears are respectively attached to the inner walls of the left side plate 3 and the right side plate 5 after being formed, and play a preliminary connecting role.
[0039] With reference to Figure 3, in order to realize the self-locking without glue and strengthen the structure, the upper edge of each side plate of the ground box is also designed with a complex inversion system. Specifically, the upper edge of the left side plate 3 is connected with the left inversion plate 15 through the fifth straight V groove 14, the upper edge of the right side plate 5 is connected with the right inversion plate 17 through the sixth straight V groove 16, the upper edge of the front side plate 7 is connected with the front inversion plate 19 through the seventh straight V groove 18, the upper edge of the rear side plate 9 is connected with the rear inversion plate 21 through the eighth straight V groove 20, and the fifth straight V groove 14, the sixth straight V groove 16, the seventh straight V groove 18 and the eighth straight V groove 20 are all two parallel and spaced apart, and the two fifth straight V grooves 14 form a left top plate, the two sixth straight V grooves 16 form a right top plate, the two seventh straight V grooves 18 form a front top plate, and the two eighth straight V grooves 20 form a rear top plate, the design of each top plate makes the ground box inner support more three-dimensional after forming; more importantly, the plug 22 is die-cut on the front and rear edges of the left and right side plates 5, and the plug hole 23 is also opened on the corresponding position of the plate body, by inserting the plug 22 of the left side plate 3 into the plug hole 23 of the right side plate 5, and inserting the plug 22 of the right side plate 5 into the plug hole 23 of the left side plate 3, the two side plates form a firm structure of mutual locking at the top. In order to cover and compress the internal connecting ears and further enhance the integrity, the free end of the left inversion plate 15 and the right inversion plate 17 is further connected with the left folding plate 26 and the right folding plate 27 through the ninth straight V groove 24 and the tenth straight V groove 25 respectively, and the first opening 28 and the second opening 29 are also reserved between the left folding plate 26 and the left inversion plate 15 and between the right folding plate 27 and the right inversion plate 17, these openings form a buckle groove for the fingers to buckle when the folding plate and the inversion plate are folded, which is convenient for disassembling the ground box inner support. In addition, the left and right sides of the front inversion plate 19 are connected with the first left compression plate 32 and the first right compression plate 33 through the tenth straight V groove 30 and the twelfth straight V groove 31, and the left and right sides of the rear inversion plate 21 are connected with the second left compression plate 36 and the second right compression plate 37 through the thirteenth straight V groove 34 and the fourteenth straight V groove 35. When finally formed, these inversion plates and folding plates are folded inward in a specific order, layer by layer, and finally all the connecting ears and internal joints are tightly compressed in the interior, forming a firm ground box inner support which does not need to be glued and relies completely on physical structure self-locking.
[0040] Referring to Figures 4-7The outer box flat folding structure 100 is die-cut and scored from a single sheet of paper, and its main body includes a bottom support plate 38, a left side cover plate 39, an upper cover plate 40, and a right side cover plate 41 connected in sequence. The cover plates are connected by first, second, and third score lines 42, 43, and 44, ensuring that the outer box can be smoothly folded open and closed. To increase the thickness and strength of the outer box, each cover plate is designed with a thickened folding structure. The bottom support plate 38 includes a first body plate 45 and a first thickened folding plate 47 and two second thickened folding plates 48 connected to it by a fourth score line 46. These folding plates are folded and pasted on the same side of the first body plate 45, making it a thick bottom plate. The left side cover plate 39 includes a second body plate 49 and two third thickened folding plates 51 connected by a fifth score line 50, which are thickened after being folded and pasted. The upper cover plate 40 includes a third body plate 52 and two fourth thickened folding plates 54 connected by a sixth score line 53, which are also thickened after being folded and pasted. The right side cover plate 41 includes a fourth body plate 55 and a fifth thickened folding plate 57 and two sixth thickened folding plates 58 connected by a seventh score line 56, which form a thickened right side plate 5 after being folded and pasted. The free end of the right side cover plate 41 also extends a plug-in plate 59. The inner box holder is pasted and fixed to the bottom support plate 38 of the outer box through its rectangular bottom plate 1. When closing the packaging box, the left side cover plate 39, the upper cover plate 40, and the right side cover plate 41 are folded and closed in sequence. Finally, the plug-in plate 59 on the right side cover plate 41 is inserted into the gap between the bottom support plate 38 and the already pasted rectangular bottom plate 1, achieving firm locking of the outer box.
[0041] The forming method of the packaging box starts from step S1, using the die-cutting process to process all the profiles, functional structures, and all linear V-slot folds of the inner box holder on a single sheet of paper at one time. In step S2, the side plates of the inner box holder are made to stand up by folding along the V-slot, and finally a self-locking and stable three-dimensional inner holder is formed by positioning the connecting ears, folding the inner turning plate and the inner folding plate, pressing the pressure plate, and interlocking the plug 22 and the socket 23, without the need for glue throughout the process. Step S3 die-cuts all the profiles, thickened folding plates, and score lines of the outer box flat folding structure 100 on another sheet of paper. In step S4, the thickened folding plates of each part of the outer box are folded and pasted to their body plates, thereby thickening the wall plates. In step S5, the bottom surface of the formed inner box holder is pasted and fixed to the bottom support plate 38 of the outer box. Finally, in step S6, the packaging box is closed by folding the cover plates of the outer box and inserting the plug-in plate 59 into the gap. The packaging box produced by this method has a stable structure, simplified production process, small transportation volume, and significantly reduced cost.
[0042] Example 2
[0043] The difference between Example 2 and Example 1 is that Figure 8The combined paperboard packaging box further comprises a rectangular surface paper 300, which is laid on the thickened folding structure after the outer box plane folding structure 100 is formed, and covers the structure by being glued on the thickened folding structure, so that the outer box plane folding structure 100 is more beautiful, the inner box support is glued on the rectangular surface paper 300, and a gap for inserting the plug 22 is formed between the rectangular bottom plate 1 of the inner box support and the rectangular surface paper 300.
[0044] While the embodiments of the application have been illustrated and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the spirit and scope of the application, which is defined by the appended claims and their equivalents.
Claims
1. A modular cardboard packaging box, characterized in that: The device includes an outer box planar folding structure and an inner box planar folding structure. Both the outer box planar folding structure and the inner box planar folding structure are formed from a single sheet of cardboard. The inner box planar folding structure includes a rectangular base plate, a left side plate and a right side plate formed on the left and right sides of the rectangular base plate, and a front side plate and a rear side plate formed on the front and rear sides of the rectangular base plate, respectively. The left and right sides of the front side plate are respectively provided with a first left connecting lug connected to the left side plate and a first right connecting lug connected to the right side plate. The left and right sides of the rear side plate are respectively provided with a second left connecting lug connected to the left side plate and a second right connecting lug connected to the right side plate. The front side plate is located away from the outer box planar folding structure and the inner box planar folding structure. A front inward flap is provided on one side of the rectangular base plate, a rear inward flap is provided on the side of the rear side plate away from the rectangular base plate, a left inward flap is provided on the side of the left side plate away from the rectangular base plate, and a right inward flap is provided on the side of the right side plate away from the rectangular base plate. Plugs are provided on both the front and rear sides of the left and right sides of the left and right sides, and each of the left and right sides has two insertion holes, which are respectively used for inserting the plugs of the left and right sides of the left and right sides. The outer box planar folding structure includes a bottom support plate, a left cover plate, a top cover plate, and a right cover plate arranged in sequence. The rectangular base plate is adhered to the bottom support plate.
2. The modular cardboard packaging box according to claim 1, characterized in that: A first straight V-groove is die-cut at the connection between the left side plate and the rectangular base plate, extending along the length of the left side of the rectangular base plate. A second straight V-groove is die-cut at the connection between the right side plate and the rectangular base plate, extending along the length of the side of the rectangular base plate. A third straight V-groove is die-cut at the connection between the front side plate and the rectangular base plate, extending along the length of the front side of the rectangular base plate. A fourth straight V-groove is die-cut at the connection between the rear side plate and the rectangular base plate, extending along the length of the rear side of the rectangular base plate.
3. A modular cardboard packaging box according to claim 2, characterized in that: The left side plate, on the side away from the rectangular base plate, has two parallel and spaced fifth straight V-grooves die-cut into it. These two fifth straight V-grooves extend along the length of the left side of the rectangular base plate, with one of them located at the connection point between the left side plate and the left inner flap. A left top plate is formed between the two fifth straight V-grooves. The right side plate, on the side away from the rectangular base plate, has two parallel and spaced sixth straight V-grooves die-cut into it. These two sixth straight V-grooves extend along the length of the right side of the rectangular base plate, with one of them located at the connection point between the right side plate and the right inner flap. A right top plate is formed between the two sixth straight V-grooves. The front side plate has two parallel and spaced seventh straight V-grooves die-cut on the side away from the rectangular base plate. The two seventh straight V-grooves extend along the length of the front side of the rectangular base plate, and one of the seventh straight V-grooves is located at the connection between the front side plate and the front inner flap. A front top plate is formed between the two seventh straight V-grooves. The rear side plate has two parallel and spaced eighth straight V-grooves die-cut on the side away from the rectangular base plate. The two eighth straight V-grooves extend along the length of the rear side of the rectangular base plate, and one of the eighth straight V-grooves is located at the connection between the rear side plate and the rear inner flap. A rear top plate is formed between the two eighth straight V-grooves.
4. A modular cardboard packaging box according to claim 1, characterized in that: The left inner flap is provided with a left inner folding plate on the side away from the left side plate, and a ninth straight V-groove extending along the length of the left side of the rectangular base plate is die-cut at the connection between the left inner folding plate and the left inner flap. The right inner flap is provided with a right inner folding plate on the side away from the left side plate, and a tenth straight V-groove extending along the length of the right side of the rectangular base plate is die-cut at the connection between the right inner folding plate and the right inner flap.
5. A modular cardboard packaging box according to claim 4, characterized in that: A first opening is provided between the left inner folding plate and the left inner flap, and a second opening is provided between the right inner folding plate and the right inner flap.
6. A modular cardboard packaging box according to claim 1, characterized in that: The left and right sides of the front inward flap are respectively provided with a first left pressure plate and a first right pressure plate. The connection between the first left pressure plate and the front inward flap is die-cut with an eleventh straight V-groove extending along the length of the left side of the rectangular base plate. The connection between the first right pressure plate and the front inward flap is die-cut with a twelfth straight V-groove extending along the length of the right side of the rectangular base plate. The left and right sides of the rear inward flap are respectively provided with a second left pressure plate and a second right pressure plate. The connection between the second left pressure plate and the rear inward flap is die-cut with a thirteenth straight V-groove extending along the length of the left side of the rectangular base plate. The connection between the second right pressure plate and the rear inward flap is die-cut with a fourteenth straight V-groove extending along the length of the right side of the rectangular base plate.
7. A modular cardboard packaging box according to claim 1, characterized in that: The bottom support plate includes a first body plate, a first thickened folding plate disposed on the side of the first body plate away from the left cover plate, and two second thickened folding plates disposed on opposite sides of the first body plate. The first thickened folding plate and the two second thickened folding plates are glued to the same side of the first body plate and cover that side. The left cover plate includes a second body plate and two third thickened folding plates disposed on opposite sides of the second body plate. The two third thickened folding plates are glued to the same side of the second body plate and cover that side. The upper cover plate includes a third body plate and two fourth thickened folding plates disposed on opposite sides of the third body plate. The two fourth thickened folding plates are folded and adhesively bonded to the same side of the third body plate and cover that side. The right cover plate includes a fourth body plate, a fifth thickened folding plate disposed on the side of the fourth body plate away from the upper cover plate, and two sixth thickened folding plates disposed on opposite sides of the body plate. The fifth thickened folding plate and the two sixth thickened folding plates are folded and adhesively bonded to the same side of the fourth body plate and cover that side.
8. A modular cardboard packaging box according to claim 1, characterized in that: The right cover plate is provided with an insert plate, and a gap is provided between the bottom support plate and the rectangular base plate for the insert plate to be inserted.
9. A modular cardboard packaging box according to claim 7, characterized in that: A first crease line is pressed and formed at the connection between the first body plate and the second body plate; a second crease line is pressed and formed at the connection between the second body plate and the third body plate; a third crease line is pressed and formed at the connection between the third body plate and the fourth body plate; a fourth crease line is pressed and formed at the connection between the first thickened folding plate and the two second thickened folding plates and the first body plate; a fifth crease line is pressed and formed at the connection between the two third thickened folding plates and the second body plate; a sixth crease line is pressed and formed at the connection between the two fourth thickened folding plates and the third body plate; and a seventh crease line is pressed and formed at the connection between the fifth thickened folding plate and the two sixth thickened folding plates and the first body plate.
10. A method for forming a modular cardboard packaging box according to any one of claims 1-9, characterized in that, Includes the following steps: Step S1, Die-cutting inner tray blank: Using the die-cutting process, the overall outline of the planar folding structure of the inner tray of the floor box, all connecting ears, inner flaps, inner folding plates, pressure plates, plugs, sockets, and straight V-grooves that form all folds are processed on a single sheet of cardboard in one step. Step S2, Folding and Forming the Inner Tray of the Floor Box: Fold the die-cut inner tray of the floor box upwards along the straight V-groove connecting it to the rectangular base plate, folding the left side panel, right side panel, front side panel, and rear side panel upwards, so that the four side panels stand upright and enclose the tray; place the first left connecting ear and the first right connecting ear on the front side panel in the corresponding positions on the inner sides of the left side panel and the right side panel, respectively; place the second left connecting ear and the second right connecting ear on the rear side panel in the corresponding positions on the inner sides of the left side panel and the right side panel, respectively; first fold the left inner folding plate on the left inner folding plate and the right inner folding plate on the right inner folding plate inwards; then ... Fold the front and rear inner flaps inward to cover and press down on the connecting ears on the front and rear side panels; then fold the left and right inner flaps inward to cover and press down on the connecting ears on the left and right side panels, the pressure plates extending from both ends of the front and rear inner flaps, and the folded left and right inner flaps, forming a multi-layer pressing structure; finally, insert the plugs on the front and rear sides of the left side panel into the corresponding holes on the right side panel, and simultaneously insert the plugs on the front and rear sides of the right side panel into the corresponding holes on the left side panel to achieve glue-free self-locking fixation of the inner tray; Step S3, Die-cut outer box blank: Use the die-cutting process to process the overall outline of the outer box planar folding structure, all the thickened folding plates, inserts and the crease lines that form the folds on another single sheet of cardstock in one go; Step S4: Thicken and glue the outer box wall panels: Fold the first thickened folding plate and two second thickened folding plates on the bottom support plate and glue them to the same side of the first body plate; fold the two third thickened folding plates on the left cover plate and glue them to the same side of the second body plate; fold the two fourth thickened folding plates on the top cover plate and glue them to the same side of the third body plate; fold the fifth thickened folding plate and two sixth thickened folding plates on the right cover plate and glue them to the same side of the fourth body plate. Step S5, Assemble the inner tray and outer box: Apply glue to the bottom surface of the rectangular base plate of the inner tray of the ground box formed in step S2, and stick it to the upper surface of the bottom support plate processed in step S4. Step S6: Close the packaging box: Fold the left cover upwards to fit the left side panel of the inner tray of the box, fold the top cover to cover the top surface of the inner tray of the box, fold the right cover downwards to fit the right side panel of the inner tray of the box, and finally insert the insert plate on the right cover into the gap between the bottom support plate and the pasted rectangular bottom plate to complete the closure of the packaging box.