Soft plastic packaging bag and bag making heat sealing knife die

Abstract

The utility model provides a kind of bag making heat sealing knife mould, and heat sealing knife mould includes heat sealing knife body base plate, plane heat sealing area and arrangement groove, heating body arrangement groove is set in heat sealing knife body base plate bottom, built-in heating body, plane heat sealing area is placed in heat sealing knife body base plate top center, edge setting chamfer structure, including first heat sealing area, second heat sealing area and third heat sealing area, three gradient settings, height decreases;Still provide a kind of soft plastic packaging bag of anti-sealing edge cracking type, including bag body, opening and anti-cracking heat sealing edge, to solve the short board of performance that there is obvious at heat sealing edge of conventional soft plastic packaging bag, and further produce a series of problems and defects, such as bag sealing edge easy cracking, bag not impact resistant, not drop resistant.

Description

Technical Field

[0001] This utility model relates to the field of processing and manufacturing technology of flexible plastic packaging bags, and in particular to a flexible plastic packaging bag with anti-seal cracking and a heat-sealing die for making the bag. Background Technology

[0002] Flexible plastic packaging bags generally refer to bags made from a single heat-sealable film material such as polyethylene (PE) or polypropylene (PP) using a bag-making machine. Alternatively, they can refer to bags made by bonding a heat-sealable film material such as polyethylene (PE) or polypropylene (PP) as a heat-sealable layer with other film materials such as polyester (PET), nylon (NY), or aluminum foil (AL) using adhesives to create a composite film, which is then processed by a bag-making machine. These packaging bags, with polymer plastics as the main material, are typically quite thin (generally between 0.025mm and 0.2mm), and their shape can change after being filled or unpacked, hence the name "flexible plastic packaging bags."

[0003] During the manufacturing process of conventional flexible plastic packaging bags, the heat-sealable material at the heat-sealing edge is in a semi-molten state under the heat-sealing die. Since the heat-sealing die typically has very sharp edges, the material at the inner edge of the heat-sealed edge is easily partially cut off under the temperature and pressure of the die. This leads to brittle welds and reduced heat-sealing strength. Furthermore, because the heat-sealing area on a conventional die is completely planar, some of the semi-molten material is often squeezed away under the temperature and pressure of the die, reducing the actual thickness of the heat-sealed material and further weakening the heat-sealing strength. This often results in the actual strength of the conventional packaging bag at the heat-sealed edge being far lower than the strength of the bag material itself, causing significant performance shortcomings at the heat-sealed edge and leading to problems and defects such as easy cracking of the seal, poor impact resistance, and poor drop resistance.

[0004] Therefore, existing technologies need further improvement and enhancement. Utility Model Content

[0005] The purpose of this utility model is to address the shortcomings of the existing technology and solve the problems existing in the existing technology.

[0006] This utility model provides a heat-sealing die for making bags. The heat-sealing die includes a heat-sealing die base plate, a planar heat-sealing area and a mounting groove. The heating element mounting groove is located at the bottom of the heat-sealing die base plate and has a built-in heating element. The planar heat-sealing area is located at the top center of the heat-sealing die base plate and has a chamfered structure at the edge. It includes a first heat-sealing area, a second heat-sealing area and a third heat-sealing area, which are arranged in a gradient with decreasing height.

[0007] In a preferred embodiment of this application, a chamfer structure is provided at the gradient connection of the first heat-sealing region, the second heat-sealing region, and the third heat-sealing region.

[0008] In a preferred embodiment of this application, the height of the planar heat-sealing area is higher than the top wall of the heat-sealing blade substrate, and the length is the same as the length of the heat-sealing blade substrate.

[0009] In a preferred embodiment of this application, the sidewall of the third heat-sealing region that is not connected to the second heat-sealing region is provided with a crescent-shaped recess. A plurality of crescent-shaped recesses are provided in succession and are recessed inward to between one-half and two-thirds of the width of the third heat-sealing region.

[0010] In a preferred embodiment of this application, the radius of the chamfer structure is 0.4mm-0.6mm.

[0011] In a preferred embodiment of this application, the width of the first heat-sealing area, the second heat-sealing area and the third heat-sealing area are 3mm-6mm, and the height decreases by 0.04-0.06mm respectively.

[0012] This application also provides a ripstop flexible plastic packaging bag, including a bag body, an opening, and a ripstop heat seal.

[0013] As a preferred embodiment of this application, the anti-cracking heat seal edge has a strong heat seal area, a medium heat seal area and a weak heat seal area from bottom to top, which correspond to the first heat seal area, the second heat seal area and the third heat seal area respectively.

[0014] In a preferred embodiment of this application, the outer edge of the weak heat-sealing area also has a heat-adhesion area, which is also formed through a third heat-sealing domain.

[0015] The beneficial effects of this utility model are as follows: 1. This application, by setting a heat-sealing die, orderly sets up a first heat-sealing area and a second heat-sealing area. The three heat-sealing zones are arranged in a gradient, with the height decreasing sequentially. When heat-sealing pressure is applied during bag making, three heat-sealing zones with different pressures are naturally formed. During actual bag making and heat sealing, some heat-sealing material that might be squeezed out of the strong heat-sealing zone will enter the medium heat-sealing zone, and even less heat-sealing material that might be squeezed out of the medium heat-sealing zone will enter the weak heat-sealing zone. In this way, the material that might be squeezed out of the heat-sealing zone under conventional heat sealing will still remain within the heat-sealing zone. The total amount of heat-sealing material remaining in the heat-sealing zone is basically the same as the bag material. This avoids the undesirable situation that may occur during conventional flat-blade heat sealing, where heat-sealing material is squeezed out of the heat-sealing zone and the heat-sealing layer becomes thinner, thus significantly weakening the heat-sealing strength.

[0016] 2. Both sides of the heat-sealing die have been rounded and chamfered. The sharp right angle transition of the conventional heat-sealing die has been changed to a rounded arc transition. This change ensures that when the outermost edge of the heat-sealing die comes into contact with the film material of the soft plastic packaging bag, it will not cause obvious damage or even half-cutting to the material of the inner and outer edges of the heat-sealing edge, thus avoiding the defect of the weld seam becoming brittle at the outermost edge of the bag heat-sealing.

[0017] 3. This application utilizes multiple crescent-shaped concave structures, enabling the novel heat-sealing die to heat-seal the material at the crescent-shaped concave areas while simultaneously heat-sealing the material. Due to the heat conduction and residual heat of the heat-sealing die, continuous material areas between the crescent-shaped concave areas are also thermally bonded, thus forming a thermal bonding zone. The narrow space design of the thermal bonding zone and its thermal bonding state greatly help to buffer the energy that the flexible plastic packaging bag needs to withstand when it is impacted or dropped, thereby further improving the heat-sealing performance of the flexible plastic packaging bag. Attached Figure Description

[0018] Figure 1 A schematic diagram of the overall structure of a bag-making heat-sealing die is provided for the utility model. Figure 2 Provided for utility model Figure 1 Enlarged view of section A; Figure 3 A schematic diagram of a flexible plastic packaging bag structure for preventing edge sealing and cracking is provided for utility model purposes; Figure 4 Provided for utility model Figure 3 Enlarged view of section B.

[0019] Figure label: 1. Heat-sealing blade base plate; 2. Planar heat-sealing area; 3. Placement groove; 4. Heating element; 5. Chamfered structure; 6. First heat-sealing area; 7. Second heat-sealing area; 8. Third heat-sealing area; 9. Crescent-shaped recess; 10. Bag body; 11. Opening; 12. Anti-cracking heat-sealing edge; 13. Heat-adhesion area; 14. Strong heat-sealing area; 15. Medium heat-sealing area; 16. Weak heat-sealing area. Detailed Implementation

[0020] To more clearly illustrate the overall concept of this application, a detailed explanation is provided below with reference to the accompanying drawings.

[0021] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0022] Furthermore, it should be understood in the description of this application that the terms "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0023] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0024] In this application, unless otherwise expressly specified and limited, the "above" or "below" of the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples.

[0025] like Figures 1 to 4 As shown, this utility model provides a bag-making heat-sealing die, including a heat-sealing die base plate 1, a planar heat-sealing area 2 and a mounting groove 3. The mounting groove 3 is located at the bottom of the heat-sealing die base plate 1 and has a built-in heating element 4. The planar heat-sealing area 2 is located at the top center of the heat-sealing die base plate 1 and has a chamfered structure 5 at its edge. It includes a first heat-sealing area 6, a second heat-sealing area 7 and a third heat-sealing area 8, which are arranged in a gradient with decreasing height.

[0026] Among them, such as Figure 1 As shown, the placement groove 3 has a T-shaped structure, and a flat heating element 4 is placed inside for heating and heat sealing the packaging bag. Chamfered structures 5 are provided at the gradient connection of the first heat sealing area 6, the second heat sealing area 7 and the third heat sealing area 8.

[0027] like Figure 1As shown, the height of the planar heat-sealing area 2 is higher than the top wall of the heat-sealing blade substrate 1, and its length is the same as that of the heat-sealing blade substrate 1, which facilitates heat sealing. Furthermore, the rounded chamfer structure 5 ensures that when the outermost edge of the heat-sealing blade comes into contact with the soft plastic packaging bag film, it will not cause significant damage or even partial cutting to the material of the inner and outer edges of the heat-sealing edge, thereby avoiding the defective situation of the weld seam becoming brittle at the outermost edge of the bag heat seal.

[0028] Furthermore, such as Figure 2 As shown, the sidewall of the third heat-sealing region 8 that is not connected to the second heat-sealing region 7 is provided with a crescent-shaped recess 9. Multiple crescent-shaped recesses 9 are provided in succession and are recessed inward to between one-half and two-thirds of the width of the third heat-sealing region 8.

[0029] As shown in the figure, the crescent-shaped recess 9 has an arc-shaped concave structure. When the material at the crescent-shaped recess 9 is heat-sealed, the heat conduction and residual heat of the heat-sealing knife form a heat-adhesive zone 13, which helps to buffer the energy that the flexible plastic packaging bag needs to withstand when it is impacted or dropped, thereby further improving the heat-sealing performance of the flexible plastic packaging bag. Specifically, for heat-sealing dies, copper, a material with excellent thermal conductivity, is preferred, followed by aluminum alloy or stainless steel. The metal material used to make the die is processed by a CNC machine tool. First, a conventional bag-making heat-sealing die is made, including: a "T-groove" to ensure that the heating element 4 can be smoothly inserted, and a heat-sealing die body protruding from the substrate. The die body is 12mm wide. The sharp right-angled edges on the left and right sides of the heat-sealing die body are chamfered, and a chamfer structure 5 with R=0.5mm is processed.

[0030] After the chamfering is completed, starting from a position 4mm wide on the plane of the bag-making heat-sealing knife, process the second heat-sealing area 7 with a width of 8mm. The height of the second heat-sealing area 7 is reduced by 0.05mm from the plane of the bag-making heat-sealing knife body, and its length is the same as that of the knife body. When processing the second heat-sealing area 7, a smooth transition with the same chamfer structure (R=0.5mm) as the first heat-sealing area 6 must be processed simultaneously.

[0031] Continuing from a position 4mm wide in the second heat-sealing area 7 of the bag-making heat-sealing knife, process the third heat-sealing area 8 with a width of 4mm. The height of the third heat-sealing area 8 is reduced by 0.05mm on the plane of the second heat-sealing area 7, while the length remains the same as the knife body. When processing the third heat-sealing area 8, a smooth transition with the same chamfer structure (R=0.5mm) as the second heat-sealing area 7 needs to be processed at the same time.

[0032] Continuous crescent-shaped recesses 9 are machined on the third heat-sealing area 8, with their length extending through the entire third heat-sealing area 8. Each crescent-shaped recess 9 has a width of 6 mm and a depth of 2.5 mm. This application also provides a flexible plastic packaging bag with anti-seal cracking, such as... Figure 3 and Figure 4 As shown, the bag includes a bag body 10, an opening 11, and a crack-resistant heat-sealed edge 12. In a preferred embodiment of this application, the crack-resistant heat-sealed edge 12 has a strong heat-sealing area 14, a medium heat-sealing area 15, and a weak heat-sealing area 16 from bottom to top, which correspond to the first heat-sealing area 6, the second heat-sealing area 7, and the third heat-sealing area 8, respectively.

[0033] Furthermore, the outer edge of the weak heat-sealing region 16 also has a heat-adhesion region 13, which is also formed through the third heat-sealing domain 8.

[0034] For any parts not mentioned in this application, existing technologies may be used or referenced.

[0035] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0036] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A heat-sealing die for making bags, characterized in that, It includes a heat-sealing blade substrate, a planar heat-sealing area, and a mounting groove. The mounting groove for the heating element is located at the bottom of the heat-sealing blade substrate and houses the heating element. The planar heat-sealing area is located at the top center of the heat-sealing blade substrate and has a chamfered edge structure. It includes a first heat-sealing area, a second heat-sealing area, and a third heat-sealing area, which are arranged in a gradient with decreasing height.

2. The bag-making heat-sealing die as described in claim 1, characterized in that, The chamfer structure is provided at the gradient connection of the first heat-sealing region, the second heat-sealing region and the third heat-sealing region.

3. A bag-making heat seal bar die as claimed in claim 2 wherein, The height of the planar heat-sealing area is higher than the top wall of the heat-sealing blade substrate, and its length is the same as the length of the heat-sealing blade substrate.

4. A bag-making heat seal bar die as claimed in claim 3 wherein, The sidewall of the third heat-sealing area that is not connected to the second heat-sealing area is provided with a crescent-shaped recess. Multiple crescent-shaped recesses are provided in succession and are recessed inward to between one-half and two-thirds of the width of the third heat-sealing area.

5. A bag-making heat seal bar die as claimed in claim 1 wherein, The radius of the chamfered structure is 0.4mm-0.6mm.

6. A bag-making heat seal bar die as defined in claim 1 wherein, The widths of the first heat-sealing area, the second heat-sealing area, and the third heat-sealing area are 3mm-6mm, and their heights decrease by 0.04-0.06mm respectively.

7. A type of flexible plastic packaging bag designed to prevent edge cracking, applicable to the heat-sealing die-cutting mold described in any one of claims 1-6, characterized in that, The packaging bag includes a bag body, an opening, and a heat-sealed edge to prevent cracking.

8. The soft plastic packaging bag of claim 7, wherein, The anti-cracking heat-sealing edge has a strong heat-sealing zone, a medium heat-sealing zone, and a weak heat-sealing zone from bottom to top, which correspond to the first heat-sealing domain, the second heat-sealing domain, and the third heat-sealing domain, respectively.

9. The soft plastic packaging bag of claim 8, wherein, The outer edge of the weak heat-sealing zone also has a heat-adhesion zone, which is also formed through a third heat-sealing domain.

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