Tear-resistant three-dimensional bag

Abstract

The utility model discloses an anti-tear three-dimensional bag, which comprises a front piece, a rear piece and a bottom piece, the upper parts of the left and right sides of the front piece are in heat-seal connection with the upper parts of the left and right sides of the rear piece, a crease is arranged in the middle of the bottom piece, the front and rear sides of the bottom piece are respectively folded downwards from the crease to form a front bottom piece and a rear bottom piece, and the bottom edge of the front bottom piece is in heat-seal connection with the bottom edge of the front piece. The left and right sides of the front bottom piece are respectively connected with the lower parts of the left and right sides of the front piece in a heat-sealing manner, the bottom edge of the rear bottom piece is connected with the bottom edge of the rear piece in a heat-sealing manner, and the left and right sides of the rear bottom piece are respectively connected with the lower parts of the left and right sides of the rear piece in a heat-sealing manner; heat sealing edges A are formed at the heat sealing positions of the front piece, the rear piece and the bottom piece, arc-shaped notches without heat sealing are formed in the junctions of the inner edges of the heat sealing edges A on the left side edge and the right side edge of the three-dimensional bag and the creases, and fillets used for sharing tearing force are arranged at the two ends of each arc-shaped notch. The utility model has the advantage of strong tear resistance.

Description

Technical Field

[0001] The utility model relates to the technical field of explosion-proof bags, in particular to a tear-resistant three-dimensional bag. Background Art

[0002] In the design of three-dimensional bags, the challenge of resisting local stress concentration is the key. The structural design of conventional three-dimensional bags is prone to force concentration at specific points, which will cause excessive local stress in the bag material and cause tearing.

[0003] Conventional three-dimensional bags are usually made of a front piece, a back piece and a bottom piece connected by heat sealing, and the bottom piece is folded from the middle into two halves, front and back.

[0004] like Figure 4 As shown in the figure, in a conventional three-dimensional bag, the intersection of the crease in the middle of the bottom film and the heat-sealed edge on the side of the three-dimensional bag is point C. Point C is the stress concentration point, where the front half of the bottom film, the back half of the bottom film, the front piece and the back piece meet. The stress concentration formed at point C is due to the sudden change in angle caused by the intersection of the crease of the bottom film and the heat-sealed edges on both sides, which leads to uneven force transmission, thus forming the starting point of tearing. When the bag is loaded with heavy objects, the stress concentration point C is subjected to the greatest tearing force, and the force is uneven, causing the bag to be easily torn.

[0005] To reduce the possibility of such tearing, Figure 5 As shown in the figure, some bags are provided with an arc-shaped inner notch at point C, but the structural effect is limited. The original intention of this design is to reduce the local stress concentration by changing the stress transfer path and expanding the stress distribution area. However, as mentioned above, simply providing an arc-shaped inner notch at point C is still not enough to solve the problem, because the stress concentration point is moved to points D and E at both ends of the arc, and these two points become new weak links again due to structural mutations. When the bag is loaded with heavy objects, the bag is still easy to be torn.

[0006] Therefore, it is necessary to further improve and perfect the prior art to overcome these deficiencies, and the present invention is made based on this situation. Utility Model Content

[0007] The utility model aims to overcome the deficiencies of the prior art and provide a three-dimensional bag with strong tear resistance.

[0008] The utility model is realized through the following technical solutions:

[0009] In order to solve the above technical problems, the utility model provides a tear-resistant three-dimensional bag, comprising a front sheet, a back sheet and a bottom sheet, the upper parts of the left and right sides of the front sheet are heat-sealed and connected with the upper parts of the left and right sides of the back sheet, a fold is arranged in the middle of the bottom sheet, the front and back sides of the bottom sheet are respectively folded downward from the fold to form a front bottom sheet and a back bottom sheet, the bottom edge of the front bottom sheet is heat-sealed and connected with the bottom edge of the front sheet, the left and right sides of the front bottom sheet are respectively heat-sealed and connected with the lower parts of the left and right sides of the front sheet, the bottom edge of the back bottom sheet is heat-sealed and connected with the bottom edge of the back sheet, and the left and right sides of the back bottom sheet are respectively heat-sealed and connected with the lower parts of the left and right sides of the back sheet;

[0010] The heat-sealed positions of the front sheet, the back sheet and the bottom sheet form heat-sealed edges A. The heat-sealed edges A on the left and right sides of the three-dimensional bag are provided with arc-shaped notches that are not heat-sealed at the intersection of their inner edges and folds. Both ends of the arc-shaped notches are provided with rounded corners for sharing the tearing force.

[0011] In order to further solve the technical problem to be solved by the utility model, in a tear-resistant three-dimensional bag provided by the utility model, the center of the arc-shaped notch is on the fold.

[0012] In order to further solve the technical problem to be solved by the utility model, in a tear-resistant three-dimensional bag provided by the utility model, the left and right side edges of the front bottom sheet and the left and right side edges of the back bottom sheet are respectively connected together.

[0013] In order to further solve the technical problem to be solved by the utility model, in a tear-resistant three-dimensional bag provided by the utility model, an opening is provided between the top edge of the front sheet and the top edge of the back sheet, and a sealing zipper is provided at the opening.

[0014] In order to further solve the technical problem to be solved by the utility model, in a tear-resistant three-dimensional bag provided by the utility model, an exhaust valve is provided on the front sheet, the back sheet or the bottom sheet.

[0015] Compared with the prior art, the utility model has the following advantages:

[0016] The improved design of the utility model introduces arc-shaped notches and reinforced rounded corners. Through these design optimizations, the structural strength of the three-dimensional bag is improved, making the bag more sturdy and durable when loaded with heavy objects. This design not only increases the service life of the product, but also improves the safety of users during use.

[0017] First, the arc-shaped notch is located at the intersection of the inner edge of the heat-sealed edge A and the fold. The arc-shaped notch helps to reduce and disperse the stress concentration originally generated at the intersection of right angles or sharp angles by changing the force transmission path.

[0018] Secondly, the rounded corners at both ends of the arc-shaped notch further strengthen the structure of the notch, because the rounded corners can disperse the stress more fully than the sharp corners. The stress can be evenly dispersed on the arc line of the arc-shaped notch and the rounded corners, reducing the damage and tearing caused by excessive stress concentration on the bag material.

[0019] In addition, rounded corners can help prevent the initiation and propagation of cracks. In material mechanics, sharp corners are the starting point for crack propagation, and rounded corner design can effectively reduce this risk. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The specific implementation of the utility model is further described in detail below with reference to the accompanying drawings, wherein:

[0021] Figure 1 It is a structural schematic diagram of the utility model;

[0022] Figure 2 It is an exploded schematic diagram of the front piece, back piece and bottom piece;

[0023] Figure 3 yes Figure 1 A partial enlarged schematic diagram of point B in the middle;

[0024] Figure 4 It is a schematic diagram of the structure of the prior art Figure 1 ;

[0025] Figure 5 It is a schematic diagram of the structure of the prior art Figure 2 . DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0027] like Figures 1 to 3 The tear-resistant three-dimensional bag shown in the figure comprises a front sheet 1, a back sheet 2 and a bottom sheet 3, wherein the upper portions of the left and right sides of the front sheet 1 (such as Figure 2 The L1 section shown in FIG. 1 and the upper portions of the left and right sides of the rear panel 2 (such as Figure 2 The bottom sheet 3 is heat-sealed to the bottom sheet 1 (see the L1 section shown in the figure). A fold 31 is provided in the middle of the bottom sheet 3. The front and rear sides of the bottom sheet 3 are folded downward from the fold 31 to form a front bottom sheet 32 ​​and a back bottom sheet 33. The bottom edge of the front bottom sheet 32 ​​is heat-sealed to the bottom edge of the front sheet 1. The left and right sides of the front bottom sheet 32 ​​are heat-sealed to the lower parts of the left and right sides of the front sheet 1 (see the L1 section shown in the figure). Figure 2 The bottom edge of the rear bottom sheet 33 is heat-sealed to the bottom edge of the rear sheet 2, and the left and right sides of the rear bottom sheet 33 are respectively heat-sealed to the lower parts of the left and right sides of the rear sheet 2 (such as Figure 2In addition, the left and right sides of the front base sheet 32 ​​and the left and right sides of the back base sheet 33 are connected together respectively. Such a structure enables the three-dimensional bag to stand.

[0028] More importantly, the heat-sealed edges A on the left and right sides of the three-dimensional bag are provided with arc-shaped notches 4 without heat sealing at the intersection of their inner edges and the folds 31, and both ends of the arc-shaped notches 4 are provided with rounded corners 41 for sharing the tearing force.

[0029] The heat-sealed positions of the front sheet 1, the back sheet 2 and the bottom sheet 3 form a heat-sealed edge A. More specifically, Figure 1-Figure 3 As shown, the heat-sealed edges A on the left and right sides of the three-dimensional bag refer to the heat-sealed edges between the upper left and right sides of the front sheet 1 and the upper left and right sides of the back sheet 2, the heat-sealed edges between the left and right sides of the front bottom sheet 32 ​​and the lower left and right sides of the front sheet 1, and the heat-sealed edges between the left and right sides of the back bottom sheet 33 and the lower left and right sides of the back sheet 2.

[0030] In the process of strengthening the design of the three-dimensional bag, the key is to improve the tear resistance of the intersection of the heat-sealed edge A and the fold 31 on the left and right sides of the three-dimensional bag. Figure 3 As shown, in the improved design of the utility model, the introduced arc-shaped notch 4 and the reinforced rounded corner 41 play a crucial role, which reduces the stress concentration generated at the intersection when the bag is loaded with heavy objects through local structural adjustment. The specific analysis is as follows:

[0031] 1) The arc-shaped notch 4 is located at the intersection of the inner edge of the heat-sealed edge A and the fold 31. The arc-shaped notch 4 helps to reduce and disperse the stress concentration originally generated at the intersection of right angles or sharp angles by changing the force transmission path.

[0032] 2) The rounded corners 41 at both ends of the arc-shaped notch 4. This design further strengthens the structure of the notch, because the rounded corners can disperse the stress more fully than the sharp corners. The stress can be evenly dispersed on the arc line of the arc-shaped notch 4 and the rounded corners 41, reducing the damage and tearing caused by excessive stress concentration on the bag material.

[0033] 3) The rounded corners 41 also help prevent the initiation and propagation of cracks. In material mechanics, sharp corners are the starting point for crack propagation, and the rounded corner design can effectively reduce this risk.

[0034] Through these design optimizations, the structural strength of the three-dimensional bag is improved, making the bag more durable when loaded with heavy objects. This design not only increases the service life of the product, but also improves the safety of users during use.

[0035] When further refining the design of the three-dimensional bag, it is a delicate and engineering-application-worthy consideration to position the center of the arc-shaped notch 4 on the bottom film fold 31. Such design considerations are as follows:

[0036] 1) Structural symmetry: By placing the center of the arc-shaped notch 4 on the fold 31 of the bottom film, it can be ensured that the heat-sealed areas of the arc-shaped notch 4 on the left and right sides are symmetrical, which helps to evenly disperse the downward pressure brought by the heavy object and make the force on both sides of the bag more balanced.

[0037] 2) Maximizing stress dispersion: The design of the arc-shaped notch 4 is to reduce stress concentration, and setting the center of the circle on the crease 31 can ensure that the arc-shaped notch 4 reduces the lateral tearing force while optimizing the force distribution in the vertical direction, because this position is the area where stress may be concentrated when the bag is subjected to vertical force.

[0038] 3) Reduce the risk of crack propagation: Since the center of the circle is located at the crease 31, the arc-shaped notch 4 naturally follows the folding line of the material, which means that any crack that may occur is more likely to spread along this preset path rather than cracking disorderly, which can control the degree and direction of damage to a certain extent.

[0039] By precisely placing the center of the arc-shaped notch 4 on the fold 31, the designers not only enhance the explosion-proof capability of the bag, but also improve its overall durability and reliability when carrying the expected internal and external loads. As a result of this careful design, the three-dimensional bag can better meet the needs of users and reduce the loss of items and potential safety risks caused by tearing.

[0040] More specifically, an opening 5 is provided between the top edge of the front sheet 1 and the top edge of the back sheet 2, and a sealing zipper 6 is provided at the opening 5. The sealing zipper 6 is also called a bone strip, and is used to open and close the opening 5. Of course, the sealing zipper 6 can also be replaced with other types of opening and closing structures, such as a magnetic zipper or a button.

[0041] In addition, in order to achieve a better exhaust effect, more specifically, an exhaust valve 7 is provided on the front sheet 1, the back sheet 2 or the bottom sheet 3 for exhausting air.

[0042] It is worth noting that in the three-dimensional bag of the present invention, the innermost layers of the front sheet 1, the back sheet 2 and the bottom sheet 3 are all made of low melting point, easily heat-sealed materials, such as PET. Such materials can be quickly melted and heat-sealed at high temperatures to form a strong waterproof sealing effect. In addition, the front sheet 1, the back sheet 2 and the bottom sheet 3 can also be made of other materials, such as polyester fiber, nylon, etc., to meet different usage requirements.

[0043] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A tear-resistant three-dimensional bag, characterized in that: The invention comprises a front sheet (1), a back sheet (2) and a bottom sheet (3), wherein the upper parts of the left and right sides of the front sheet (1) are heat-sealed to the upper parts of the left and right sides of the back sheet (2), a fold (31) is provided in the middle of the bottom sheet (3), the front and rear sides of the bottom sheet (3) are folded downward from the fold (31) to form a front bottom sheet (32) and a back bottom sheet (33), the bottom edge of the front bottom sheet (32) is heat-sealed to the bottom edge of the front sheet (1), the left and right sides of the front bottom sheet (32) are heat-sealed to the lower parts of the left and right sides of the front sheet (1), and the left and right sides of the front bottom sheet (32) are heat-sealed to the lower parts of the left and right sides of the front sheet (1). The bottom edge of the rear bottom sheet (33) is heat-sealed to the bottom edge of the rear sheet (2), and the left and right sides of the rear bottom sheet (33) are heat-sealed to the lower parts of the left and right sides of the rear sheet (2) respectively; the heat-sealed positions of the front sheet (1), the rear sheet (2) and the bottom sheet (3) form a heat-sealed edge A, and the heat-sealed edges A on the left and right sides of the three-dimensional bag are provided with an arc-shaped notch (4) that is not heat-sealed at the intersection of the inner edge and the fold (31), and the two ends of the arc-shaped notch (4) are provided with rounded corners (41) for sharing the tearing force.

2. The tear-resistant three-dimensional bag according to claim 1, characterized in that: The center of the arc-shaped notch (4) is on the fold (31).

3. The tear-resistant three-dimensional bag according to claim 1, characterized in that: The left and right sides of the front bottom sheet (32) and the left and right sides of the back bottom sheet (33) are respectively connected together.

4. The tear-resistant three-dimensional bag according to claim 1, characterized in that: An opening (5) is provided between the top edge of the front sheet (1) and the top edge of the back sheet (2), and a sealing zipper (6) is provided at the opening (5).

5. The tear-resistant three-dimensional bag according to claim 1, characterized in that: An exhaust valve (7) is provided on the front sheet (1), the back sheet (2) or the bottom sheet (3).

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