A pultrusion preform structure, its mold and its manufacturing method

Abstract

The present invention relates to the technical field of composite material manufacturing processes. More specifically, it relates to a pultrusion preform structure, its mold, and its manufacturing method, including a hollow guide plate. The hollow guide plate is provided with a cavity having openings at both ends. One opening of the cavity is a horizontal opening, and the other opening is an arc-shaped opening. The horizontal opening is in the shape of the product when unfolded, and the arc-shaped opening is in the shape of the mold opening of the pultrusion mold. The interior of the cavity is at the same height everywhere, and there is a smooth and continuous transition between the horizontal opening and the arc-shaped opening of the cavity. The present invention can achieve the continuous transition of the fiber cloth, minimize problems such as wrinkles, loops, and misalignment occurring at the preform part during the traction process, reduce the workload of manual alignment during the pultrusion process, and ensure the stability of the entire process.

Description

Technical Field

[0001] The present invention relates to the technical field of composite material manufacturing processes, and more specifically, to a pultrusion preform structure, its mold, and its manufacturing method. Background Art

[0002] As one of the main preparation processes in the manufacturing process of composite material products, the pultrusion process has the characteristics of high automation and good product consistency, and its share in the composite material field is increasing. In the pultrusion process, the design of the pultrusion mold and the preform tooling is an important part of the entire process. The quality of the design and processing of the mold and the preform will directly determine the efficiency of pultrusion production, or even its success or failure. At the same time, it also determines the appearance and quality of the pultruded product. Moreover, the preform structure also determines the external dimensions of the product and whether the process can proceed smoothly. If the preform tooling part is not reasonably designed, it is impossible to achieve a smooth transition of the reinforcing fiber from the raw material rack to the mold opening, making it difficult to control the movement of the yarn bundle and the reinforcing fabric, resulting in the occurrence of defective products and waste products.

[0003] With the development of carbon fiber composite materials in fields such as rail vehicles, the design requirements based on isotropic composite materials are widely applied. Therefore, the pultrusion method using multi-axial fabric as the main reinforcing fiber has become the main way to realize such designs into products. For pultrusion using fiber fabric as the main material, the difficulty of designing the preform part has been greatly improved. It often requires multiple deformations of multiple groups of preform plates to achieve the deformation of the fiber fabric. This type of design not only increases the difficulty of the entire process, but also in the design of multiple preform plates, each time passing through the preform plate will bring problems such as wrinkles and offsets of discontinuous deformation.

[0004] In the prior art, different preform structures correspond to different products, with obvious product specificity, such as CNl06079484A, a new pultrusion preform positioning device; CN107877890A, a pultrusion preform device for fiberglass; CN201621368407, a stepped preform die set for pultrusion; CN108381951A, a preform mold for pultrusion; CN09016570A, a preform tooling for pultrusion of comb-shaped walking plates, etc. There is no solution in the above prior art that can adapt to the preform design with reinforcing fiber fabric as the main pultrusion reinforcing material.

[0005] Therefore, it is necessary to design a pultrusion preform structure for using reinforcing fiber fabric as the main pultrusion reinforcing material. Summary of the Invention

[0006] In order to overcome the deficiencies existing in the prior art, a pultrusion preform structure, its mold and its manufacturing method are provided, which can achieve continuous transition of the fiber cloth, and reduce problems such as wrinkles, pockets, and displacement occurring at the preformed part during the traction process.

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0008] A pultrusion preform structure includes a hollow guide plate. The hollow guide plate is provided with a cavity with openings at both ends. One opening of the cavity is a horizontal opening, and the other opening is an arc-shaped opening.

[0009] There is a smooth and continuous transition between the horizontal opening and the arc-shaped opening of the cavity.

[0010] To ensure the smooth preforming of the reinforcing fiber cloth in the cavity, the cavity is of the same height everywhere inside, and the height of the cavity is 1.2 to 2 times the thickness of the fiber cloth.

[0011] To ensure the preformed shape of the reinforcing fiber cloth, the hollow guide plate is made of a plastic thin plate with equal thickness. The horizontal opening is in the shape of the product when unfolded, and the arc-shaped opening is in the shape of the mold opening of the pultrusion mold.

[0012] Further, the plastic thin plate is one of polyethylene, polypropylene, and polycarbonate.

[0013] To ensure the smooth and continuous transition from the horizontal opening end to the mold opening part, the length of the hollow guide plate is greater than or equal to 5 times the length of the horizontal opening.

[0014] To achieve batch preforming, a plurality of hollow guide plates are provided. They are nested in a large-small manner, and a support material is filled between adjacent hollow guide plates and they are fixed to each other.

[0015] A pultrusion preform structure mold includes an upper mold plate and a lower mold plate. A forming cavity is formed between the upper mold plate and the lower mold plate, and the structure of the forming cavity is the same as the outer shape structure of the hollow guide plate.

[0016] A manufacturing method for a pultrusion preform structure includes:

[0017] S1. Splice plastic thin plates into a hollow structure with openings at both ends, and seal the joints of adjacent plastic thin plates.

[0018] S2. Pass the fiber cloth through the hollow structure, and place the hollow structure between the upper mold plate and the lower mold plate.

[0019] S3. Heat and apply pressure to form the hollow structure into a hollow guide plate structure.

[0020] S4. Withdraw the fiber cloth, and the hollow guide plate is obtained.

[0021] Further, it further includes: S5. Combining multiple hollow guide plates in a nested manner of different sizes, and filling and fixing the space between adjacent hollow guide plates with supporting materials.

[0022] Further, it further includes: S6. Fixing the hollow guide plate to the connection mounting frame, and docking the arc-shaped opening of the hollow guide plate with the die section of the pultrusion equipment.

[0023] The beneficial effects of the present invention compared with the prior art are as follows:

[0024] The present invention adopts a continuous transition integral structure, combines the traditional preformed structure of multiple preformed plates, realizes the continuous deformation of the reinforcing fiber cloth during the traction process, and realizes the smooth traction and continuous deformation of the reinforcing fiber cloth by controlling the internal space size of the thin structure. It avoids problems such as offset, wrinkle, and pocketing that are prone to occur during the pultrusion process of the reinforcing fiber cloth as the main reinforcing material, and the setting of the tooling is simple, reasonable, and highly integrated, making the operation very short and efficient. Description of the Drawings

[0025] The following will further elaborate on the specific implementation manners of the present invention through the drawings.

[0026] Figure 1 It is a schematic diagram of the hollow guide plate structure of the present invention;

[0027] Figure 2 is Figure 1 a partial enlarged view of A in

[0028] Figure 3 It is a schematic diagram of the fiber cloth forming of the present invention;

[0029] Figure 4 It is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0030] Figure 5 It is a schematic diagram of the structure of Embodiment 3 of the present invention.

[0031] In the figure: 1 - hollow guide plate, 11 - horizontal opening, 12 - arc-shaped opening, 2 - supporting material, 3 - upper die template, 4 - lower die template, 5 - forming cavity, 6 - cavity, 7 - fiber cloth. Specific Embodiment

[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0033] Example 1:

[0034] As Figures 1 to 3 shown, a pultrusion preform structure includes a hollow guide plate 1. The hollow guide plate 1 is first formed by splicing equal-thickness plastic sheets into a hollow structure, and the edges are sealed with an adhesive or a plastic sealing machine, and then the hollow structure is bent into a hollow guide plate 1 with the required shape through a forming die; the hollow guide plate 1 is provided with a cavity 6 with openings at both ends. One opening of the cavity 6 is a horizontal opening 11, and the horizontal opening 11 is the shape of the product when unfolded. The other opening is an arc-shaped opening 12, and the arc-shaped opening 12 is the shape of the die opening of the pultrusion die. The length of the hollow guide plate 1 is greater than or equal to 5 times the length of the horizontal opening 11, and there is a smooth and continuous transition between the horizontal opening 11 and the arc-shaped opening 12 of the cavity 6.

[0035] The height inside the cavity 6 is the same everywhere, and the height of the cavity 6 is 1.2 - 2 times the thickness of the fiber cloth 7 to ensure the forming quality of the fiber cloth 7.

[0036] The plastic sheet is one of polyethylene, polypropylene, and polycarbonate.

[0037] Operation steps:

[0038] Fix the preform structure at the front end of the die section of the pultrusion equipment. The horizontal opening 11 is the starting end of the preform, and the arc-shaped opening 12 is the ending end of the preform. Feed the reinforcing fiber cloth 7 through the horizontal opening and achieve a smooth transition of the reinforcing fiber cloth from a plane to the designed shape through the cavity 6.

[0039] Example 2:

[0040] As Figure 4 shown, to improve the preforming efficiency, a plurality of hollow guide plates 1 are provided. In a nested manner of different sizes, a support material 2 is filled between adjacent hollow guide plates 1 and they are fixed to each other, so that multiple fiber cloths can be preformed simultaneously.

[0041] Example 3:

[0042] As Figure 5 shown, a die for a pultrusion preform structure includes an upper die plate 3 and a lower die plate 4. A forming cavity 5 is formed between the upper die plate 3 and the lower die plate 4. The structure of the forming cavity 5 is the same as the outer shape structure of the hollow guide plate 1, and the preform structure is bent and formed through preforming.

[0043] Example 4

[0044] A manufacturing method for a pultrusion preform structure includes:

[0045] S1. Splice plastic thin plates into a hollow structure with both ends open, and seal the joints of adjacent plastic thin plates;

[0046] S2. Pass the fiber cloth 7 through the hollow structure, and place the hollow structure between the upper die plate 3 and the lower die plate 4 of the mold;

[0047] S3. Heat and apply pressure to form the hollow structure into the shape of the hollow guide plate 1;

[0048] S4. Withdraw the fiber cloth 7, and thus obtain the hollow guide plate 1;

[0049] S5. Combine multiple hollow guide plates 1 in a large-small nested manner, and fill and fix the space between adjacent hollow guide plates 1 with the support material 2;

[0050] S6. Connect and fix the hollow guide plate 1 to the mounting frame, and dock the arc-shaped opening 12 of the hollow guide plate 1 with the die section of the pultrusion equipment.

[0051] The above only elaborates on the preferred embodiments of the present invention in detail. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those of ordinary skill in the art, various changes can be made without departing from the gist of the present invention, and all such changes should be included within the protection scope of the present invention.

Claims

1. A pultruded preform structure, characterized in that: It includes a hollow guide plate (1), the hollow guide plate is provided with a cavity with openings at both ends, one opening of the cavity is a horizontal opening (11), and the other opening is an arc-shaped opening (12); There is a smooth and continuous transition between the horizontal opening (11) and the arc-shaped opening (12) of the cavity; There are multiple hollow guide plates (1), which are nested in size. Between adjacent hollow guide plates (1), a support material (2) is filled and they are fixed to each other.

2. The pultrusion preform structure according to claim 1, characterized in that: The interior of the cavity is at the same height everywhere, and the height of the cavity is 1.2 to 2 times the thickness of the fiber cloth.

3. The pultrusion preform structure according to claim 1, characterized in that: The hollow guide plate (1) is made of a plastic thin plate with equal thickness. The horizontal opening (11) is the shape of the product when unfolded, and the arc-shaped opening (12) is the shape of the die opening of the pultrusion die.

4. A pultrusion preform structure according to claim 3, wherein: The plastic thin plate is one of polyethylene, polypropylene, and polycarbonate.

5. A pultrusion preform structure according to claim 1, characterized in that: The length of the hollow guide plate (1) is greater than or equal to 5 times the length of the horizontal opening.

6. A mold for the pultrusion preformed structure according to any one of claims 1 to 5, characterized in that: It includes an upper die template (3) and a lower die template (4). A forming cavity (5) is formed between the upper die template (3) and the lower die template (4), and the structure of the forming cavity (5) is the same as the outer shape structure of the hollow guide plate (1).

7. A manufacturing method of a pultrusion preform structure, characterized in that: S1. Splice plastic thin plates into a hollow structure with openings at both ends, and seal the joints of adjacent plastic thin plates; S2. Pass the fiber cloth through the hollow structure, and place the hollow structure between the upper die template (3) and the lower die template (4); S3. Heat and apply pressure to form the hollow structure into the structure of the hollow guide plate (1); S4. Withdraw the fiber cloth to obtain the hollow guide plate (1).

8. A method for manufacturing a pultrusion preform structure according to claim 7, characterized in that: It also includes: S5. Combine multiple hollow guide plates (1) in a size-nested manner, and fill and fix the adjacent hollow guide plates (1) with a support material (2).

9. A method for manufacturing a pultrusion preform structure according to claim 7, characterized in that: It also includes: S6. Connect and fix the hollow guide plate (1) to the mounting frame, and dock the arc-shaped opening of the hollow guide plate (1) with the die section of the pultrusion equipment.

Images