Composite latex mold and preparation method of air bag

Abstract

The invention provides a composite latex mold and a preparation method of an air bag. The composite latex mold comprises a core rod and a plurality of flexible supporting sets fixed to the core rod. The multiple flexible supporting sets are arranged around the axis of the core rod at intervals. Each flexible supporting set comprises two flexible supporting blades, and the two flexible supporting blades are arranged around the axis of the core rod at intervals. The hardness of the flexible supporting blade is larger than or equal to 60, the compression set ranges from 5% to 10%, and the elastic modulus is larger than or equal to 0.6 kgf / mm < 2 >. According to the technical scheme, the rigid core rod and the flexible supporting set with elasticity are adopted to form the composite latex mold, and when the air bag is prepared, demolding of the air bag can be facilitated through elastic deformation of the flexible supporting set. In addition, due to the elastic performance of the flexible supporting set, the diameter of the ball handle of the air bag can be made to be small.

Description

Technical Field

[0001] The present application relates to the field of balloon technology, and in particular to a composite latex mold and a method for preparing an air bag. Background Art

[0002] The general film-forming process for latex products is the dipping method, which is also called the ion deposition method in the latex process. The ion deposition method is a gelling method used to convert liquid latex into a solid product. Its basic principle is: by applying an electric field in the latex, the electric field force is used to cause the latex particles to deposit on the electrode to form a thin film. This method can accurately control the thickness and quality of the film. During the processing of latex products, a large amount of metal cations are attached to the mold surface by dipping the coagulant with metal cations. During the dipping process of latex, the liquid emulsion reacts with the metal cations to deposit the emulsion particles on the mold surface to form a film. Subsequent processing steps such as demoulding and vulcanization are required to become the final product. However, the strength of the film formed by this type of dipping production process is relatively low, and it is necessary to go through a vulcanization process to increase its yield limit.

[0003] The existing impregnation production mold is a rigid mold, which has the problem of demolding difficulties when producing special-shaped parts with different diameters such as airbags and balloons. In particular, during the demolding process of products with large diameter differences, when the small-diameter part passes through the large-diameter part, the expansion multiple of the small-diameter part is large. Once it exceeds its yield limit, the uncured film will break, resulting in a decrease in production efficiency and an increase in cost. The products that can be produced by existing rigid molds have certain shape and outer diameter ratio (the ratio of the diameter of the widest part of the mold to the diameter of the narrowest part of the mold) restrictions, and cannot meet the requirements of producing special-shaped products. Summary of the invention

[0004] The invention object of the present application is to provide a composite latex mold and a method for preparing an airbag, so as to improve the production effect of the airbag.

[0005] In a first aspect, a composite latex mold is provided, comprising: a core rod, and a plurality of flexible support groups fixed on the core rod; wherein the plurality of flexible support groups are arranged at intervals around the axis of the core rod; each flexible support group comprises two flexible support blades, and the two flexible support blades are arranged at intervals around the axis of the core rod; The flexible support blade has a Shore A hardness of ≥60A, a compression permanent deformation of 5% to 10%, and an elastic modulus of ≥0.6 kgf / mm 2 .

[0006] In the above technical solution, by using a rigid core rod and an elastic flexible support group to form a composite latex mold, when preparing the airbag, the airbag can be easily demoulded by the elastic deformation of the flexible support group. In addition, due to the elastic performance of the flexible support group, the diameter of the handle of the airbag can be made smaller.

[0007] In a specific implementable solution, along the length direction of the core rod, the outer edge of the flexible supporting blade is an elliptical arc; and the ratio of the diameter of the core rod to the minor axis corresponding to the elliptical arc is less than 1:3.

[0008] In a specific feasible solution, a plurality of V-shaped slits are provided on the core rod; the plurality of V-shaped slits are arranged at intervals on the side wall of the core rod along the circumference of the core rod; The flexible support groups correspond to the V-shaped gaps one by one; the two flexible support blades in each flexible support group are an integrated structure; and the two flexible support blades are inserted into the corresponding V-shaped gaps and fixed.

[0009] In a specific implementable solution, along the length direction of the rod core, one end of each V-shaped gap is open, and the open end is the insertion end of a corresponding flexible support group.

[0010] In a specific feasible solution, the flexible support group is clamped and fixed to the core rod through a corresponding V-shaped gap, or is bonded and fixed to the core rod through an adhesive.

[0011] In a specific implementable solution, the number of the flexible support groups is two, and the four flexible support blades in the two flexible support groups are evenly arranged around the axis of the core rod.

[0012] In a specific feasible solution, the core rod is made of 304 stainless steel.

[0013] In a specific feasible solution, the flexible support blade is a flexible support blade made of a silicone composite material.

[0014] In a second aspect, a method for preparing an airbag is provided, using any of the composite latex molds described above; the method comprises the following steps: The composite latex mold is heated to a set temperature, and then the composite latex mold is immersed in a coagulant and dried; The composite latex mold is impregnated with latex, and then leached with hot water and dried; Air is injected into the demoulding port to separate the adhesive film from the mold; wherein, during the separation, the flexible supporting blades can undergo elastic deformation.

[0015] In the above technical solution, by using a rigid core rod and an elastic flexible support group to form a composite latex mold, when preparing the airbag, the airbag can be easily demoulded by the elastic deformation of the flexible support group. In addition, due to the elastic performance of the flexible support group, the diameter of the handle of the airbag can be made smaller.

[0016] In a specific implementable solution, the set temperature is 75 to 80 degrees Celsius. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments provided according to the present disclosure and should not be regarded as limiting the scope of the present disclosure.

[0018] Figure 1 A schematic diagram of the structure of a composite latex mold provided in an embodiment of the present application; Figure 2 A schematic cross-sectional view of a composite latex mold provided in an embodiment of the present application.

[0019] Reference numerals: Core rod 10, flexible support group 20, flexible support blade 21 DETAILED DESCRIPTION In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings.

[0020] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in one or more embodiments of this specification should be understood by people with ordinary skills in the field to which this disclosure belongs. The "first", "second" and similar words used in one or more embodiments of this specification do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0021] To facilitate understanding of the composite latex mold provided in the embodiment of the present application, its application scenario is first explained. The composite latex mold provided in the embodiment of the present application is used in the production process of airbags. Current airbags use rigid molds during production. The rigid mold includes a core rod and blades. During production, after the product is formed into a film by an ion deposition method, the strength of the film itself is relatively small. During the processing of various special-shaped parts, there are products with inconsistent inner and outer diameters. During the demolding process of such product processing, when the small-sized caliber part passes through the large-sized caliber part, the expansion multiple of the small-sized caliber part is large, and when it exceeds its yield limit, the unvulcanized film will break. To this end, the embodiment of the present application provides a composite latex mold to improve the inflation effect of dual-mode balloons, which will be described in detail below in conjunction with specific drawings and embodiments.

[0022] refer to Figure 1 and Figure 2 As shown, Figure 1 The schematic diagram of the structure of the composite latex mold provided in the embodiment of the present application is shown. Figure 2 A schematic cross-sectional view of a composite latex mold provided in an embodiment of the present application is shown. The composite latex mold provided in an embodiment of the present application includes a rigid core rod 10 and flexible blades. The core rod 10 is a cylindrical structure for supporting the blades. During the production process, latex is deposited on the core rod 10 and the blades. One end of the core rod 10 is a demolding port. After the production is completed, the formed airbag can be peeled off from the demolding port to fall off the mold. During the specific preparation, the natural latex airbag is formed on the outside of the composite latex mold. The specific process is that a coagulant layer is attached to the composite latex mold, and then the composite latex mold is impregnated with natural latex to obtain a natural latex film, and the film is evenly covered on the surface of the mold.

[0023] In the specific setting, the blade is a flexible support blade 21 made of flexible material. For the convenience of description, multiple flexible support blades 21 are divided into a group in pairs and named as flexible support group 20. Among them, multiple flexible support groups 20 are fixed on the core rod 10, and multiple flexible support groups 20 are arranged at intervals around the axis of the core rod 10. As described above, each flexible support group 20 includes two flexible support blades 21, and when the two flexible support blades 21 are arranged, the two flexible support blades 21 are arranged at intervals around the axis of the core rod 10. That is, multiple flexible support blades 21 are arranged circumferentially around the core rod 10 in a circle. So that during production, the main structure of the airbag can be formed by multiple flexible support blades 21.

[0024] In the embodiment of the present application, the performance of the flexible support blade 21 meets the following requirements: the hardness of the flexible support blade 21 is ≥60, the compression permanent deformation is 5%~10%, and the elastic modulus is ≥0.6 kgf / mm 2That is, the flexible support blade 21 provided in the embodiment of the present application has certain elasticity and support, so that the latex can be deposited on the flexible support blade 21 and keep it in a certain shape. In addition, during demoulding, the flexible support blade 21 can also be changed in flexibility so that the flexible support blade 21 can be elastically deformed in the direction of being wound around the axis of the core rod 10 on the core rod 10, so as to facilitate the demoulding of the formed airbag on the composite latex mold.

[0025] In the actual production process, during the processing of various types of special-shaped airbags, there are products with non-uniform inner and outer diameters. Therefore, in the composite latex mold provided in the embodiment of the present application, the core rod 10 in the middle part is designed to be a rigid material, and the flexible support blade 21 is made of an elastic material. The flexible support blade 21 can be bent and folded during the demolding process, so that the outer and inner diameter ratio (the ratio of the diameter of the widest part of the mold to the diameter of the narrowest part of the mold) can be reduced, so that the rubber film is always deformed within its yield strength during the demolding process. After the rubber material is formed into a film, the strength of the rubber film is enhanced by a leaching process, and the leached product has a certain resilience.

[0026] It can be seen from the above description that the composite latex mold provided in the embodiment of the present application improves the traditional rigid material mold into a composite material mold of a rigid body and a soft body, making it feasible to process some latex product special-shaped parts with an inner and outer diameter ratio of less than 1:3. This is because the tensile strength of the film on the unvulcanized mold surface is low. During the demolding process, when the expansion rate of the film on the core rod 10 is greater than 300%, the film of the entire core rod 10 is prone to permanent plastic deformation or fracture. This makes it difficult to process such special-shaped parts. Therefore, the use of a composite mold combining a soft body and a rigid body allows the elastic material to bend first inside the film during demolding, reducing the volume required to pass through the demolding port of the core rod 10. It also reduces the expansion elongation of the film at the demolding port on the core rod 10.

[0027] It can be seen from the above description that the composite latex mold provided in the embodiment of the present application is composed of a rigid core rod 10 and an elastic flexible support group 20. When preparing the airbag, the airbag can be easily demoulded by the elastic deformation of the flexible support group 20. In addition, due to the elastic performance of the flexible support group 20, the diameter of the handle of the airbag can be made smaller.

[0028] In the specific setting, the composite latex mold provided in the embodiment of the present application uses a rigid core rod 10 and a flexible support blade 21 made of elastic material. The core rod 10 is a rigid material (including stainless steel, aluminum and other materials that are not easily deformed), and the flexible support blade 21 is made of a polymer soft material. The connection between the core rod 10 and the flexible support blade 21 can be adhesive bonding, or the flexible support blade 21 is embedded in the core rod 10 after processing the core rod 10, and then the connection between the core rod 10 and the flexible support blade 21 is fixed with an adhesive material.

[0029] In a specific embodiment, since the flexible support blade 21 is made of elastic material, its width can be made larger. For example, along the length direction of the core rod 10, the outer edge of the flexible support blade 21 is an elliptical arc; the ratio of the diameter of the core rod 10 to the short axis corresponding to the elliptical arc is less than 1:3. Figure 2 As shown in , the flexible support blade 21 provided in the embodiment of the present application is an elliptical blade. The long axis of the elliptical blade is parallel to the axis of the core rod 10, while the short axis is perpendicular to the axis of the core rod 10. Due to the elastic properties of the flexible support blade 21, the flexible support blade 21 can be bent and folded when demolding, so the ratio of the diameter of the core rod 10 to the short axis of the elliptical blade can be made smaller, that is, the short axis of the flexible support blade 21 can be made larger. Figure 2 As shown in , the diameter of the core rod 10 is d, the short axis of the flexible supporting blade 21 is D, and d:D<1:3.

[0030] For example, in a specific solution, as shown in Table 1, the diameter of the core rod 10 is 15 mm, and the short axis of the flexible supporting blade 21 is 80 mm, and the ratio between the two is 3:16, which is much smaller than 1:3.

[0031] Table 1

[0032] It can be seen from Table 1 that the composite latex mold provided in the embodiment of the present application can be provided with the flexible support blade 21, so that when the entire mold is used to prepare an airbag, the opening of the ball handle of the prepared airbag (the size corresponding to the core rod 10) can be smaller, while the width (the part corresponding to the short axis of the flexible support blade 21) is larger. In addition, due to the performance of the flexible support blade 21, the film is not prone to excessive deformation during demolding, thereby improving the preparation effect of the airbag.

[0033] When the flexible support group 20 is connected to the core rod 10, different methods can be used. For example, in one example, the flexible support group 20 can be embedded in the core rod 10. For example, a plurality of V-shaped gaps 11 are provided on the core rod 10; the plurality of V-shaped gaps 11 are arranged at intervals along the circumference of the core rod 10 on the side wall of the core rod 10. The length direction of the V-shaped gap 11 is along the axial direction of the core rod 10, and its cross section is a V shape. Both ends of the V-shaped gap 11 are open, such as Figure 2 As shown in , the two ends of the V-shaped slot 11 refer to the two ends of the V-shape, that is, the V-shaped slot 11 forms two openings on the side wall of the core rod 10 whose length direction extends along the axial direction of the core rod 10 .

[0034] The V-shaped gap 11 is a structure that is matched with the flexible support group 20 in a one-to-one correspondence. In the specific setting, the two flexible support blades 21 in each flexible support group 20 are an integrated structure, and the two flexible support blades 21 are inserted into the corresponding V-shaped gap 11 and fixed. That is, in the embodiment of the present application, the two flexible support blades 21 are an integral structure, and the supporting integral structure is embedded in the V-shaped gap 11, and the two ends are exposed, and the exposed part is the flexible support blade 21. When this structure is adopted, the two flexible support blades 21 are matched with the core rod 10 as a whole, which can ensure the structural strength of the flexible support blade 21 when connected to the core rod 10.

[0035] In an optional embodiment, in order to facilitate the flexible support group 20 to be embedded in the corresponding V-shaped gap 11, in the specific setting, along the length direction of the rod core; one end of each V-shaped gap 11 is open, and the open end is the insertion end of the corresponding flexible support group 20. Exemplarily, one end of the core rod 10 is a demoulding port, and an opening is set at the other end of the V-shaped gap 11 close to the core rod 10. When the flexible support group 20 is embedded in the core rod 10, the flexible support group 20 can be inserted into the V-shaped gap 11 from the opening, thereby facilitating the assembly of the flexible support group 20. In addition, after the flexible support blade 21 is assembled into the V-shaped gap 11, the opening of the V-shaped gap 11 can be blocked to ensure the stability of the connection between the flexible support blade 21 and the core rod 10.

[0036] When the flexible support blades 21 are matched with the core rod 10, they can be fixed in different ways. For example, in a specific embodiment, the flexible support group 20 is clamped and fixed to the core rod 10 by the corresponding V-shaped gap 11. That is, the flexible support blades 21 are fixed by clamping with the two side walls of the V-shaped groove of the core rod 10. During specific assembly, the flexible support blades 21 and the core rod 10 adopt an interference fit, and the flexible support blades 21 undergo elastic deformation when inserted into the V-shaped gap 11 on the core rod 10 to ensure the stability of the two when they are matched. In another embodiment, it can also be bonded and fixed to the core rod 10 by adhesive. That is, after the flexible support blades 21 are assembled to the V-shaped gap 11, the flexible support blades 21 can be bonded and fixed to the core rod 10 by adhesive.

[0037] In an optional solution, the bending part of the V-shaped gap 11 adopts an arc transition, so as to facilitate the cooperation between the flexible support blade 21 and the core rod 10 and avoid excessive bending when the flexible support group 20 is assembled to the corresponding V-shaped gap 11.

[0038] In the example of the present application, the number of the flexible support groups 20 is not specifically limited. For example, the number of the flexible support groups 20 is two, and the four flexible support blades 21 in the two flexible support groups 20 are evenly arranged around the axis of the core rod 10. Of course, in addition to the four flexible support blades 21 in the above example, the number of the flexible support blades 21 can also be six, eight, or other different numbers.

[0039] In an optional embodiment, the material used for the core rod 10 is 304 stainless steel. 304 stainless steel has both good hardness and stability, so that it can support the flexible support blade 21 and cooperate with the deposition of latex. In addition, the flexible support blade 21 can be a flexible support blade 21 made of a silicone composite material. The silicone composite material has good elasticity, so that it can deposit latex and has a good recovery effect after folding.

[0040] The present application also provides a method for preparing an airbag, using any of the above-mentioned composite latex molds; the method comprises the following steps: Step 001: heating the composite latex mold to a set temperature, and then dipping the composite latex mold into a coagulant and drying it; Specifically, the composite latex mold is heated to 80°C in a temperature box, and then the mold is dipped in a coagulant, and then the coagulant is dried at 80°C for 15 minutes. Ps: Zhuzhou Rubber Research and Design Institute Co., Ltd. designed and manufactured this mold in the process of producing special airbags. The minimum diameter of the customized airbag is ≤15mm, and the widest part of the airbag is 145mm.

[0041] Step 002: impregnating the composite latex mold with latex, leaching with hot water and then drying; Specifically, the dried mold is impregnated with latex, and after the impregnation is completed, the film is dried, and the drying conditions are 80° C. for 15 minutes.

[0042] Step 003: Inject air into the demoulding port to separate the film from the mold; during the separation, the flexible support blades 21 may undergo elastic deformation.

[0043] Specifically, air is injected into the demoulding port after drying to separate the rubber mold from the mold, and then the soft mold is rolled to an appropriate size and then removed to obtain an unvulcanized high-strength airbag rubber film.

[0044] In the above technical solution, by using a rigid core rod 10 and an elastic flexible support group 20 to form a composite latex mold, when preparing the airbag, the airbag can be easily demoulded by the elastic deformation of the flexible support group 20. In addition, due to the elastic performance of the flexible support group 20, the diameter of the handle of the airbag can be made smaller.

[0045] One or more embodiments of this specification are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of one or more embodiments of this specification should be included in the scope of protection of this disclosure.

[0046] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A composite latex mold, characterized in that: include: A core rod, and a plurality of flexible support groups fixed on the core rod; wherein the plurality of flexible support groups are arranged at intervals around the axis of the core rod; each flexible support group comprises two flexible support blades, and the two flexible support blades are arranged at intervals around the axis of the core rod; The flexible support blade has a Shore A hardness of ≥60A, a compression permanent deformation of 5% to 10%, and an elastic modulus of ≥0.6kgf / mm 2 .

2. The composite latex mold according to claim 1, characterized in that: Along the length direction of the core rod, the outer edge of the flexible supporting blade is an elliptical arc; the ratio of the diameter of the core rod to the short axis corresponding to the elliptical arc is less than 1:

3.

3. The composite latex mold according to claim 2, characterized in that: The core rod is provided with a plurality of V-shaped slits; the plurality of V-shaped slits are arranged at intervals on the side wall of the core rod along the circumference of the core rod; The flexible support groups correspond to the V-shaped gaps one by one; the two flexible support blades in each flexible support group are an integrated structure; and the two flexible support blades are inserted into the corresponding V-shaped gaps and fixed.

4. The composite latex mold according to claim 3, characterized in that: Along the length direction of the rod core, one end of each V-shaped gap is open, and the open end is the insertion end of a corresponding flexible support group.

5. The composite latex mold according to claim 3, characterized in that: The flexible support group is clamped and fixed to the core rod through corresponding V-shaped gaps, or is bonded and fixed to the core rod through adhesive.

6. The composite latex mold according to claim 1, characterized in that: The number of the flexible support groups is two, and the four flexible support blades in the two flexible support groups are evenly arranged around the axis of the core rod.

7. The composite latex mold according to any one of claims 1 to 6, characterized in that: The core rod is made of 304 stainless steel.

8. The composite latex mold according to claim 7, characterized in that: The flexible supporting blade is a flexible supporting blade made of a silica gel composite material.

9. A method for preparing an airbag, characterized in that: Using the composite latex mold as described in any one of claims 1 to 8; the method comprises the following steps: The composite latex mold is heated to a set temperature, and then the composite latex mold is immersed in a coagulant and dried; The composite latex mold is impregnated with latex, and then leached with hot water and dried; Air is injected into the demoulding port to separate the adhesive film from the mold; wherein, during the separation, the flexible supporting blades can undergo elastic deformation.

10. The method for preparing an airbag according to claim 9, characterized in that: The set temperature is 75 to 80 degrees Celsius.

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