A thickened packaging box

By designing a thickened packaging box and utilizing the folding properties of cardboard to create a three-dimensional space, the problem of insufficient protection for protruding parts in traditional packaging methods is solved, achieving effective cushioning protection for the product and reducing the risk of damage during transportation.

CN224529283UActive Publication Date: 2026-07-21CIG SHANGHAI CO LTD
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
CIG SHANGHAI CO LTD
Filing Date
2025-08-01
Publication Date
2026-07-21

AI Technical Summary

Technical Problem

Traditional packaging methods cannot effectively protect the protruding parts of products, and the cushioning performance of heavy products is insufficient during transportation, leading to product damage and increased economic losses.

Method used

Design a thickened packaging box that uses the folding properties of cardboard to create a three-dimensional space. By layering and bonding thickened boards and side panels, the thickness and strength of the sides are increased, and the protruding parts of the product are protected by a support structure.

Benefits of technology

It effectively protects protruding parts of the product during transportation, reduces the risk of damage, is easy to operate and inexpensive, and is suitable for large-scale production.

✦ Generated by Eureka AI based on patent content.

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Abstract

The utility model relates to packing box technical field, especially a kind of thickening packing box. Packing box is folded by a sheet of paperboard along crease line, and paperboard includes bottom plate, upper side plate, lower side plate, left side plate and right side plate. Upper side plate, lower side plate, left side plate and right side plate are respectively connected to the first side edge, second side edge, third side edge and fourth side edge of bottom plate. The left and right side edges of upper side plate are respectively connected with first thickening plate and second thickening plate;The left and right side edges of lower side plate are respectively connected with third thickening plate and fourth thickening plate;Upper side plate, lower side plate, left side plate and right side plate are folded inwards along crease line and form the containing cavity of packing box;First thickening plate, third thickening plate fold towards containing cavity and are laminated with left side plate, second thickening plate, fourth thickening plate fold towards containing cavity and are laminated with right side plate. Thus increase the thickness of the side of packing box, and the protruding part of product is protected by the thickened side of packing box.
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Description

Technical Field

[0001] This utility model relates to the field of packaging box technology, and in particular to a thickened packaging box. Background Technology

[0002] In the packaging industry, with the increasing prevalence of complex-structured products such as electronic devices, some products have protruding antenna heads or other protruding structural components. These protruding parts are highly fragile and cannot withstand any external pressure. Once subjected to external pressure or direct impact during transportation or use, they are easily damaged, thus affecting the normal function of the product. Furthermore, when the product itself is heavy, traditional packaging methods often lack sufficient cushioning performance, failing to provide adequate protection. This makes the product susceptible to vibration and impact during transportation, leading to economic losses for manufacturers and consumers, and increasing the costs of after-sales repair and replacement. Utility Model Content

[0003] The purpose of this utility model is to provide a thickened packaging box that can elevate the protruding parts of the product after packaging and provide effective cushioning protection for the product.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0005] This utility model provides a thickened packaging box, which is made of a piece of cardboard folded along the crease line. The cardboard includes:

[0006] Base plate;

[0007] The upper side panel is connected to the first side edge of the base plate;

[0008] The lower side plate is connected to the second side plate on the bottom plate, which is opposite to the first side plate.

[0009] The left side panel is connected to the third side of the base plate;

[0010] The right side plate is connected to the fourth side plate on the bottom plate, which is opposite to the third side plate.

[0011] The left and right sides of the upper side panel are respectively connected to the first thickened plate and the second thickened plate;

[0012] The left and right sides of the lower side panel are respectively connected to the third and fourth thickened plates;

[0013] The upper side panel, lower side panel, left side panel, and right side panel are folded together along the crease lines to form the receiving cavity of the packaging box;

[0014] The first and third thickened plates are folded toward the receiving cavity and laminated with the left side plate, while the second and fourth thickened plates are folded toward the receiving cavity and laminated with the right side plate.

[0015] Preferably, the first thickened plate, the second thickened plate, the third thickened plate, and the fourth thickened plate are all divided into at least two sub-plates by crease lines parallel to the first side.

[0016] Preferably, the left side panel is divided into a first left side panel, a second left side panel, and a third left side panel that are connected in sequence by a crease line parallel to the third side;

[0017] The right side panel is divided into a first right side panel, a second right side panel, and a third right side panel that are connected in sequence by crease lines parallel to the fourth side;

[0018] The first upper wing plate and the first lower wing plate are connected to the third left side plate;

[0019] The third right side plate is connected to the second upper wing plate and the second lower wing plate.

[0020] Preferably, after folding, the first upper wing plate and the second upper wing plate are attached to the inner side of the upper side plate, and the first lower wing plate and the second lower wing plate are attached to the inner side of the lower side plate.

[0021] Preferably, the upper side panel is divided into a first upper side panel, a second upper side panel, and a third upper side panel that are connected in sequence by crease lines parallel to the first side; after folding, the first upper side panel and the second upper side panel are stacked, and the third upper side panel is stacked with the bottom panel.

[0022] Preferably, the lower side panel is divided into a first lower side panel, a second lower side panel, and a third lower side panel that are connected in sequence by crease lines parallel to the second side; after folding, the first lower side panel and the second lower side panel are stacked, and the third lower side panel is stacked with the bottom plate.

[0023] Preferably, the left side plate and the right side plate are respectively provided with a first snap-fit ​​part, and the bottom plate is provided with a first snap-fit ​​groove that matches the first snap-fit ​​part. After folding, the first snap-fit ​​part snaps into the first snap-fit ​​groove.

[0024] Preferably, the lower side plate is provided with a second snap-fit ​​part, and the upper side plate is provided with a second snap-fit ​​groove that matches the second snap-fit ​​part. After folding, the second snap-fit ​​part snaps into the second snap-fit ​​groove.

[0025] Compared with the prior art, this utility model has significant progress:

[0026] The thickened packaging box of this utility model mainly utilizes the folding characteristics of cardboard. During the folding process, the side panels and the thickened plate are folded towards each other along the fold lines, so that the originally flat cardboard forms a three-dimensional cavity. At the same time, the thickened plate and the side panels are folded and attached, increasing the thickness and strength of the side of the packaging box. Thus, the thickened side of the packaging box provides support and protection for the protruding parts of the product. Attached Figure Description

[0027] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0028] Figure 1 This is an isometric view of the thickened packaging box according to an embodiment of the present invention;

[0029] Figure 2 This is a plan view of the thickened packaging box according to an embodiment of the present utility model, wherein the thickened plate has two sub-plates;

[0030] Figure 3 This is a plan view of the thickened packaging box according to an embodiment of the present utility model, wherein the thickened plate has three sub-plates;

[0031] Figure 4 This is a structural diagram of a thickened packaging box according to an embodiment of the present invention when applied to a product with protruding parts.

[0032] Explanation of reference numerals in the attached drawings: 1-Base plate; 11-First side; 12-Second side; 13-Third side; 14-Fourth side; 2-Upper side plate; 21-First thickened plate; 22-Second thickened plate; 23-First upper side plate; 24-Second upper side plate; 25-Third upper side plate; 3-Lower side plate; 31-Third thickened plate; 32-Fourth thickened plate; 33-First lower side plate; 34-Second lower side plate; 35-Third lower side plate ; 4-Left side plate; 41-First left side plate; 42-Second left side plate; 43-Third left side plate; 431-First upper wing plate; 432-First lower wing plate; 5-Right side plate; 51-First right side plate; 52-Second right side plate; 53-Third right side plate; 531-Second upper wing plate; 532-Second lower wing plate; 6-Receiving cavity; 7-First snap-fit ​​part; 8-First snap-fit ​​groove; 9-Second snap-fit ​​part; 10-Second snap-fit ​​groove. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this utility model clearer, the various embodiments of this utility model will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the various embodiments of this utility model to facilitate a better understanding of this application. However, the technical solutions claimed in the claims of this application can be implemented even without these technical details and with various variations and modifications based on the following embodiments.

[0034] like Figures 1 to 4 The image shows one embodiment of the thickened packaging box provided by this utility model.

[0035] See Figures 1 to 4 The thickened packaging box in this embodiment is formed by folding a piece of cardboard along the crease line. The cardboard includes a base plate 1, an upper side plate 2, a lower side plate 3, a left side plate 4, and a right side plate 5. It should be noted that in the description of this utility model, the "upper" side refers to... Figure 2 The top side of the paper, the bottom side refers to Figure 2 The bottom side of the paper, the "left" side refers to Figure 2 The left side of the paper, the "right" side refers to Figure 2 The right side of the paper.

[0036] The upper side panel 2 is connected to the first side 11 of the base plate 1, the lower side panel 3 is connected to the second side 12 of the base plate 1 opposite to the first side 11, the left side panel 4 is connected to the third side 13 of the base plate 1, and the right side panel 5 is connected to the fourth side 14 of the base plate 1 opposite to the third side 13. The left and right sides of the upper side panel 2 are respectively connected to the first thickened plate 21 and the second thickened plate 22, and the left and right sides of the lower side panel 3 are respectively connected to the third thickened plate 31 and the fourth thickened plate 32. The upper side panel 2, lower side panel 3, left side panel 4, and right side panel 5 are folded together along the crease lines to form the receiving cavity 6 of the packaging box. The first thickened plate 21 and the third thickened plate 31 are folded towards the receiving cavity 6 and overlapped with the left side panel 4, while the second thickened plate 22 and the fourth thickened plate 32 are folded towards the receiving cavity and overlapped with the right side panel 5.

[0037] To enhance the thickness, multiple thickened panels are layered and bonded with the left side panel 4 and the right side panel 5, significantly increasing the side thickness of the packaging box. This gives the box better compressive strength, enabling it to withstand greater external forces and reducing the possibility of deformation due to external pressure. When packaging products with protruding parts, the box fastens to both ends of the product, with the protruding side of the product corresponding to the thickened side of the box. The thickness of the thickened side of the box is not less than the extension length of the protruding part, thus supporting it. Therefore, during transportation, the packaged product will come into contact with other items through the thickened side of the box, thus protecting the protruding part of the product.

[0038] In terms of usability, the packaging box has a reasonable structural design and can be assembled simply by folding, without the need for complicated processes or adhesives. This makes it easy to operate and suitable for large-scale production and use. At the same time, the thickened design of the packaging box effectively protects the product and reduces the risk of damage during transportation and storage.

[0039] Regarding cost, although thicker boards have been added, since the entire packaging box is still made from a single piece of cardboard folded together, the material and production costs will not increase significantly, making it both economical and practical.

[0040] Therefore, the thickened packaging box in this embodiment mainly utilizes the folding characteristics of cardboard. During the folding process, the side panels and the thickened plate are folded towards each other along the fold lines, so that the originally flat cardboard forms a three-dimensional cavity. At the same time, the thickened plate and the side panels are folded and fitted together, increasing the thickness and strength of the sides of the packaging box. The thickened sides of the packaging box provide support and protection for the protruding parts of the product.

[0041] See Figure 2 and Figure 3 Preferably, the first thickened plate 21, the second thickened plate 22, the third thickened plate 31, and the fourth thickened plate 32 are all divided into at least two sub-plates by crease lines parallel to the first side edge 11. Pre-folding multiple sub-plates along the crease lines allows the thickened plates to be stacked and bonded with the left side plate 4 and the right side plate 5, further increasing the side thickness of the packaging box and ensuring that the side thickness of the packaging box is not less than the extension length of the protruding part of the product, thereby enabling the packaging box to better fit and protect the product.

[0042] See Figure 2 and Figure 3Preferably, the left side panel 4 is divided into a first left side panel 41, a second left side panel 42, and a third left side panel 43 connected in sequence by crease lines parallel to the third side 13; the right side panel 5 is divided into a first right side panel 51, a second right side panel 52, and a third right side panel 53 connected in sequence by crease lines parallel to the fourth side 14. When folding the left side panel 4, the first left side panel 41 is folded first, making it perpendicular to the bottom panel 1; then the second left side panel 42 is folded to the right, making it parallel to the bottom panel 1; finally, the third left side panel 43 is folded towards the bottom panel 1, so that the third left side panel 43 is overlapped and bonded to the first thickened panel 21 and the third thickened panel 31. The third left side panel 43 is provided with a first snap-fit ​​part 7, and the bottom plate 1 is provided with a first snap-fit ​​groove 8 that matches the first snap-fit ​​part 7. Therefore, when folding the third left side panel 43 toward the bottom plate 1, the first snap-fit ​​part 7 is snapped into the first snap-fit ​​groove 8, thereby fixing the folded left side panel 4. When folding the right side panel 5, firstly fold the first right side panel 51 so that the first right side panel 51 is perpendicular to the bottom plate 1, then fold the second right side panel 52 to the left so that the second right side panel 52 is parallel to the bottom plate 1, and finally fold the third right side panel 53 toward the bottom plate 1 so that the third right side panel 53 is stacked and bonded with the second thickened plate 22 and the fourth thickened plate 32. The third right side panel 53 is provided with a first snap-fit ​​part 7, and the bottom plate 1 is provided with a first snap-fit ​​groove 8 that matches the first snap-fit ​​part 7. Therefore, when folding the third right side panel 53 toward the bottom plate 1, the first snap-fit ​​part 7 is snapped into the first snap-fit ​​groove 8, thereby fixing the folded right side panel 5.

[0043] In this embodiment, a first upper wing plate 431 and a first lower wing plate 432 are connected to the third left side panel 43; a second upper wing plate 531 and a second lower wing plate 532 are connected to the third right side panel 53. Preferably, after folding, the first upper wing plate 431 and the second upper wing plate 531 are attached to the inner side of the upper side panel 2, thereby increasing the thickness of the upper part of the packaging box; the first lower wing plate 432 and the second lower wing plate 532 are attached to the inner side of the lower side panel 3, thereby increasing the thickness of the lower part of the packaging box. Thus, by thickening the upper and lower parts of the packaging box with the first upper wing plate 431 and the second upper wing plate 531, and the first lower wing plate 432 and the second lower wing plate 532 respectively, the increased side thickness can effectively buffer external impacts, reduce the risk of product damage during transportation and storage, and improve product safety.

[0044] See Figure 2 and Figure 3Preferably, the upper side panel 2 is divided into a first upper side panel 23, a second upper side panel 24, and a third upper side panel 25 connected sequentially by crease lines parallel to the first side edge 11. After folding, the first upper side panel 23 and the second upper side panel 24 are stacked, and the third upper side panel 25 is stacked with the bottom plate 1. When folding the upper side panel 2, the first upper side panel 23 is folded first so that it is perpendicular to the bottom plate 1. Then, the second upper side panel 24 is folded towards the bottom plate 1 so that it is parallel to the first upper side panel 23. Since the first upper wing plate 431 and the second upper wing plate 531 are folded and attached to the inner side of the folded upper side panel 2, the first upper wing plate 431 and the second upper wing plate 531 are sandwiched between the first upper side panel 23 and the second upper side panel 24 after folding. Finally, the third upper side panel 25 is folded so that it is perpendicular to the second upper side panel 24 and is parallel to and attached to the bottom plate 1.

[0045] See Figure 2 and Figure 3 Preferably, the lower side panel 3 is divided into a first lower side panel 33, a second lower side panel 34, and a third lower side panel 35 connected sequentially by crease lines parallel to the second side edge 12. After folding, the first lower side panel 33 and the second lower side panel 34 are fitted together, and the third lower side panel 35 is stacked on top of the bottom plate 1. When folding the lower side panel 3, the first lower side panel 33 is folded first so that it is perpendicular to the bottom plate 1. Then, the second lower side panel 34 is folded towards the bottom plate 1 so that it is parallel to the first lower side panel 33. Since the first lower wing plate 432 and the second lower wing plate 532 are folded and fitted to the inner side surface of the lower side panel 3, after folding, the first lower wing plate 432 and the second lower wing plate 532 are sandwiched between the first lower side panel 33 and the second lower side panel 34. Finally, the third lower side panel 35 is folded so that it is perpendicular to the second lower side panel 34, and the third lower side panel 35 is parallel and fitted to the third upper side panel 25.

[0046] In this embodiment, preferably, a second snap-fit ​​portion 9 is provided on the outer side of the third lower side plate 35, and a second snap-fit ​​groove 10 adapted to the second snap-fit ​​portion 9 is provided at the connection between the second upper side plate 24 and the third upper side plate 25. After folding, the second snap-fit ​​portion 9 snaps into the second snap-fit ​​groove 10, thereby ensuring that the packaging box maintains a stable shape during use and preventing loosening and deformation.

[0047] The process of forming the thickened packaging box in this embodiment using a single sheet of cardboard is as follows:

[0048] Step 1: Fold the first thickened plate 21, the second thickened plate 22, the third thickened plate 31, and the fourth thickened plate 32 along the crease lines to form sub-plates, so that the folded sub-plates are stacked. Then, fold the first thickened plate 21 and the second thickened plate 22 so that the first thickened plate 21 and the second thickened plate 22 are perpendicular to the first upper side plate 23, and fold the third thickened plate 31 and the fourth thickened plate 32 so that the third thickened plate 31 and the fourth thickened plate 32 are perpendicular to the first lower side plate 33.

[0049] Step 2: Fold the first upper side panel 23 along the crease line, and then fold the first lower side panel 33, so that the first upper side panel 23 and the first lower side panel 33 are perpendicular to the bottom panel 1. At this time, the first thickened plate 21 and the third thickened plate 31 are stacked and bonded on the left side of the cardboard, and the second thickened plate 22 and the fourth thickened plate 32 are stacked and bonded on the right side of the cardboard.

[0050] Step 3: Fold the first left side panel 41 so that it is perpendicular to the bottom plate 1. Then fold the second left side panel 42 to the right so that it is parallel to the bottom plate 1. Finally, fold the third left side panel 43 towards the bottom plate 1 so that it is parallel to the folded first left side panel 41, with the first thickened plate 21 and the third thickened plate 31 sandwiched between the first left side panel 41 and the third left side panel 43. While folding the third left side panel 43, fold the first upper wing panel 431 and the first lower wing panel 432 outwards and towards each other so that they are parallel and perpendicular to the third left side panel 43. After folding, the first upper wing panel 431 fits against the inner side of the first upper side panel 23, and the first lower wing panel 432 fits against the inner side of the first lower side panel 33. Finally, the first snap-fit ​​portion 7 of the third left side panel 43 is snapped into the first snap-fit ​​groove 8, thereby fixing the folded left side panel 4.

[0051] Step four: Fold the first right side panel 51 so that it is perpendicular to the bottom plate 1. Then fold the second right side panel 52 to the left so that it is parallel to the bottom plate 1. Finally, fold the third right side panel 53 towards the bottom plate 1 so that it is parallel to the folded first right side panel 51. The second thickened plate 22 and the fourth thickened plate 32 are sandwiched between the first right side panel 51 and the third right side panel 53. While folding the third right side panel 53, fold the second upper wing panel 531 and the second lower wing panel 532 outwards and towards each other so that they are parallel and perpendicular to the third right side panel 53. After folding, the second upper wing panel 531 is in contact with the inner side of the first upper side panel 23, and the second lower wing panel 532 is in contact with the inner side of the first lower side panel 33. Finally, the first snap-fit ​​portion 7 of the third right side panel 53 is snapped into the first snap-fit ​​groove 8, thereby fixing the folded right side panel 5.

[0052] Step 5: Fold the second upper side plate 24 towards the base plate 1 so that the second upper side plate 24 is parallel to the first upper side plate 23. Since the first upper wing plate 431 and the second upper wing plate 531 are attached to the inner side of the folded upper side plate 2, the folded first upper wing plate 431 and the second upper wing plate 531 are sandwiched between the first upper side plate 23 and the second upper side plate 24. Then fold the third upper side plate 25 so that the third upper side plate 25 is perpendicular to the second upper side plate 24 and is parallel and attached to the base plate 1.

[0053] Step six: Fold the second lower side panel 34 towards the base plate 1 so that the second lower side panel 34 is parallel to the first lower side panel 33. Since the first lower wing plate 432 and the second lower wing plate 532 are folded and attached to the inner side of the lower side panel 3, after folding, the first lower wing plate 432 and the second lower wing plate 532 are sandwiched between the first lower side panel 33 and the second lower side panel 34. Then fold the third lower side panel 35 so that the third lower side panel 35 is perpendicular to the second lower side panel 34, and the third lower side panel 35 is parallel and attached to the third upper side panel 25. Finally, engage the second snap-fit ​​part 9 of the third lower side panel 35 into the second snap-fit ​​groove 10 to ensure that the packaging box maintains a stable shape during use and prevents loosening and deformation.

[0054] Those skilled in the art will understand that the above embodiments are specific examples of implementing the present invention, and in practical applications, various changes can be made to them in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A thickened packaging box, characterized in that, The packaging box is formed by folding a piece of cardboard along the crease line, the cardboard comprising: Base plate (1); Upper side plate (2), the upper side plate (2) is connected to the first side edge (11) of the bottom plate (1); The lower side plate (3) is connected to the second side plate (12) on the bottom plate (1) opposite to the first side plate (11); Left side plate (4), the left side plate (4) is connected to the third side (13) of the bottom plate (1); The right side plate (5) is connected to the fourth side plate (14) on the bottom plate (1) opposite to the third side plate (13); The left and right sides of the upper side plate (2) are respectively connected to a first thickened plate (21) and a second thickened plate (22); The lower side plate (3) is connected to a third thickened plate (31) and a fourth thickened plate (32) on its left and right sides, respectively. The upper side panel (2), the lower side panel (3), the left side panel (4) and the right side panel (5) are folded together along the crease lines to form the receiving cavity (6) of the packaging box; The first thickened plate (21) and the third thickened plate (31) are folded toward the receiving cavity (6) and are stacked and bonded to the left side plate (4), and the second thickened plate (22) and the fourth thickened plate (32) are folded toward the receiving cavity and are stacked and bonded to the right side plate (5).

2. The thickened packaging box according to claim 1, characterized in that, The first thickened plate (21), the second thickened plate (22), the third thickened plate (31) and the fourth thickened plate (32) are all divided into at least two sub-plates by crease lines parallel to the first side (11).

3. The thickened packaging box according to claim 1, characterized in that: The left side panel (4) is divided into a first left side panel (41), a second left side panel (42) and a third left side panel (43) connected in sequence by crease lines parallel to the third side edge (13); The right side plate (5) is divided into a first right side plate (51), a second right side plate (52) and a third right side plate (53) connected in sequence by crease lines parallel to the fourth side edge (14); The third left side plate (43) is connected to the first upper wing plate (431) and the first lower wing plate (432); The third right side plate (53) is connected to a second upper wing plate (531) and a second lower wing plate (532).

4. The thickened packaging box according to claim 3, characterized in that, After folding, the first upper wing plate (431) and the second upper wing plate (531) are attached to the inner side of the upper side plate (2), and the first lower wing plate (432) and the second lower wing plate (532) are attached to the inner side of the lower side plate (3).

5. The thickened packaging box according to claim 1, characterized in that, The upper side plate (2) is divided into a first upper side plate (23), a second upper side plate (24) and a third upper side plate (25) connected in sequence by crease lines parallel to the first side edge (11); after folding, the first upper side plate (23) and the second upper side plate (24) are stacked, and the third upper side plate (25) is stacked with the bottom plate (1).

6. The thickened packaging box according to claim 1, characterized in that, The lower side plate (3) is divided into a first lower side plate (33), a second lower side plate (34) and a third lower side plate (35) connected in sequence by a crease line parallel to the second side edge (12); after folding, the first lower side plate (33) and the second lower side plate (34) are stacked, and the third lower side plate (35) is stacked with the bottom plate (1).

7. The thickened packaging box according to claim 1, characterized in that, The left side plate (4) and the right side plate (5) are respectively provided with a first snap-fit ​​part (7), and the bottom plate (1) is provided with a first snap-fit ​​groove (8) that is adapted to the first snap-fit ​​part (7). After folding, the first snap-fit ​​part (7) is snapped into the first snap-fit ​​groove (8).

8. The thickened packaging box according to claim 1, characterized in that, The lower side plate (3) is provided with a second snap-fit ​​part (9), and the upper side plate (2) is provided with a second snap-fit ​​groove (10) that is adapted to the second snap-fit ​​part (9). After folding, the second snap-fit ​​part (9) is snapped into the second snap-fit ​​groove (10).