Device and method for preparing unit layer of long and short fiber combined structure

Abstract

The invention discloses a unit layer preparation device and method of a long and short fiber combined structure, fibers in a net tire layer are implanted into a fiber cloth layer through crawler-type needling and special needling action with hook teeth of X-layer fiber cloth and Y-layer net tire, a synchronous pointing device can introduce long fibers in different sewing modes among multiple unit layers, and the unit layers are uniformly distributed. According to the method, a consolidated and stable integrated unit layer is formed, the conformability of all components of the unit layer can be consistent, the net tire layer of the weak layer connection structure is endowed with a certain mechanical property, and meanwhile, different pointing modes can be adjusted to adapt to unit layers with different volume densities. The unit layers with different thicknesses and different densities are effectively connected through different pointing modes, the problem that the shape follow-up performance of all the units is different is solved, and the layer laying error rate is reduced; meanwhile, the production procedures are reduced, and the needling forming efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of textile weaving, and in particular relates to a device and method for preparing a unit layer of a long and short fiber combination structure. Background Art

[0002] The unit layer is an important structure of the molded needle-punched preform, which is usually composed of a fiber cloth layer and a fiber mesh layer. The number and specifications of the fiber cloth layer and the mesh layer are adjusted to meet different unit layer structure designs. Due to the changes in the unit layer structure design, it is usually necessary to lay the fiber cloth layer and the mesh layer multiple times, which is a cumbersome process. In addition, during the preparation of the unit layer, the mesh and the layer are weak planar connection structures. When wrapping the special-shaped preform, it is easy to deform or even break due to stretching, affecting the interlayer connection and density uniformity of the preform. The above shortcomings in the use of the unit layer seriously restrict the preparation cost and molding quality of the preform. Therefore, it is urgent to establish a method and device for preparing a continuous unit layer of a long and short fiber combination structure to solve the problems generated during the use of the preform unit layer. Summary of the invention

[0003] The purpose of the present invention is to solve the problem that the current preform unit layer is loose in structure, resulting in cumbersome procedures during use, and is prone to wrinkles and holes, which restrict the high-quality and low-cost development of needle-punched preforms. A continuous integrated preform unit layer preparation method is provided, and the specific method is to use X layers of fiber cloth + Y layers of mesh tires through crawler-type needling, and the special needles with hook teeth can implant the fibers in the mesh tire layer into the fiber cloth layer. The synchronous grouting device can introduce long fibers with different suturing methods between multiple unit layers to form a consolidated and stable integrated unit layer, which can achieve consistent conformability of each component of the unit layer, and give the mesh tire layer of the weak layer connection structure certain mechanical properties. At the same time, different grouting methods can be adjusted to adapt to unit layers with different volume densities.

[0004] In order to achieve the purpose of the present invention, the present invention discloses a unit layer preparation device of a long and short fiber combination structure, comprising a first web tire unwinding roller, a laying roller, a second web tire unwinding roller, a unit layer pre-pressing roller, a crawler-type needling device, a crawler needle plate, a special needle, a flat needle plate, a grouting needle, a grouting rotating roller, a needle rotating clamp, a needle receiving clamp, and a winding roller; the first web tire unwinding roller, the laying roller, and the second web tire unwinding roller are arranged on the same frame and are installed in a vertically staggered manner, and the unit layer pre-pressing roller is placed at the rear ends of the first web tire unwinding roller, the laying roller, and the second web tire unwinding roller; a crawler-type needling device is installed behind the unit layer pre-pressing roller; the crawler-type needling device comprises a crawler needle plate, a special needle and a flat needling device; the flat needle The pricking device includes a needling moving part and a flat needle plate, and the needling moving part includes a driving wheel and a driven wheel; the track needle plate and the flat needle plate are arranged with needle holes arranged in a regular pattern, the track needle plate is installed on the driving wheel and the driven wheel, and the needling driving wheel drives the track needle plate to move; the flat needle plate is installed opposite to the track needle plate, and special needles are installed in the needle holes of the track needle plate and the flat needle plate respectively; a hooking device is arranged at the tail end of the crawler type needling device, and the hooking device includes a hooking needle, a hooking rotating roller, a needle rotating clamp and a needle receiving clamp, the needle rotating clamp clamps the tail end of the hooking needle, and is installed on the hooking rotating roller, and the needle receiving clamp is fixed at the position of the hooking needle movement path; the winding roller is installed at the tail end of the frame, connected to the motor, and can move actively.

[0005] In order to achieve the purpose of the present invention, the present invention also discloses a method for preparing a unit layer of a long and short fiber combination structure, comprising the following steps:

[0006] Step 1: According to the unit layer requirements, X layers of multi-angle fiber cloth and Y layers of web tire are respectively rolled up and placed on X+Y unwinding rollers. After unwinding, the fiber cloth layer and the web tire layer are tensioned by the unwinding speed;

[0007] Step 2, the X-layer multi-angle fiber cloth and the Y-layer web tire are passed through a unit layer pre-pressing roller to form a loose unit layer without interlayer connection;

[0008] Step 3, adjusting the spacing and speed of the crawler-type needling device, and adjusting the speeds of the conveyor belt and the winding device to be consistent;

[0009] Step 4: convey the stacked multi-angle fiber cloth and web tire to the crawler needling device, and start the crawler needling device simultaneously. Under the needling action of special long and short needles with hook teeth, the short fibers in the Y-layer web tire are introduced into the X-layer fiber cloth layer, and X+Y units are consolidated into one unit layer;

[0010] Step 5: After reinforcement, the prefabricated unit layer that is consolidated and stable enters the jointing device;

[0011] Step 6: Keep the unwinding roller and the winding roller rotating continuously, adjust the rotation mode of the jointing needle, and then repeat the above steps to connect the multiple unit layers with continuous long fibers;

[0012] Step 7: The unit layers after needle suture are collected into a roll by a winding device.

[0013] Furthermore, in step 1, the numbers of X and Y are both greater than or equal to 1; the surface density of the fiber cloth layer and the web layer can be adjusted at will according to the design of the unit layer structure.

[0014] Furthermore, the mesh layer includes a mesh formed by various glass fibers such as carbon fiber mesh, quartz fiber mesh or alumina fiber mesh; the multi-angle fiber cloth layer includes a fiber cloth layer formed by various glass fibers such as carbon fiber cloth, quartz fiber cloth or alumina fiber cloth; the multi-angle fiber cloth layer includes satin cloth, spread cloth and weftless cloth.

[0015] Furthermore, in step 2, the unit layer pre-pressing roller used for the web layer is in a weak pressure state of 0-5N to keep the web layer in a fluffy state.

[0016] Furthermore, in step 3, the conveyor belt speed is coordinated with the grouting action in the grouting device, and there is a pause during the grouting process, and the grouting needle continues to move after exiting the fabric.

[0017] Furthermore, in step 4, the spacing between the crawler needling devices is greater than or equal to the theoretical thickness value of the preform unit layer.

[0018] Furthermore, the hook needle rotation method in step 6 includes the hook needle rotating 180° clockwise first and then rotating 180° counterclockwise, and the conveying device is indirectly paused according to the suturing requirements; or the hook needle rotates 180° clockwise, and the conveying device continuously advances according to the suturing requirements.

[0019] Furthermore, the grouting device in step 6 adjusts the conveying speed of the device according to the requirements of unit layers with different volume densities, and can be controlled in accordance with the requirements of stitching dot arrays with different volume densities. The greater the conveying speed, the smaller the stitching dot array density; the grouting device adjusts the spacing between the hook needle and the unit layer according to the stitching dot array. The larger the stitching spacing, the larger the spacing between the hook needle and the unit layer; the tail end of the grouting device pulls the yarn, and the needle introduces the yarn into the unit layer after passing through the cloth layer.

[0020] Furthermore, the preform unit layer in step 7 is in a tensioned state when being rolled up, and the fiber cloth layer and the web layer in the unit layer are stably consolidated without falling off or wrinkling due to transportation transfer.

[0021] Compared with the prior art, the significant progress of the present invention is as follows: 1) When preparing the needle punched preform, there is no need to stack multiple layers, which reduces the production process and improves the efficiency of needle punching; 2) Preparing multiple units into an integrated unit layer solves the problem of different conformability between the units, reduces the error rate of plying, can effectively avoid wrinkles caused by plying, and improves product quality; 3) Short fibers in the mesh and long fibers in the stitching can be introduced between multiple unit layers to enhance the effective connection between unit layers. 4) Unit layers of different thicknesses and densities are effectively connected through different grouting methods.

[0022] In order to more clearly illustrate the functional characteristics and structural parameters of the present invention, further description is given below in conjunction with the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0024] Figure 1 It is a schematic diagram of a method and a device for preparing a unit layer of a long and short fiber combination structure;

[0025] The reference numerals in the figure are: 1-first mesh unwinding roller; 2-laying roller; 3-second mesh unwinding roller; 4-unit layer pre-pressing roller; 5-crawler-type needling device; 6-crawler needle plate; 7-special needle; 8-flat needle plate; 9-sewing needle; 10-sewing rotating roller; 11-sewing needle rotating clamp; 12-sewing needle receiving clamp; 13-winding roller. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only 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 ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0027] A unit layer preparation device of a long and short fiber combination structure comprises a first web tire unwinding roller 1, a laying roller 2, a second web tire unwinding roller 3, a unit layer pre-pressing roller 4, a crawler-type needling device 5, a crawler needle plate 6, a special needle 7, a flat needle plate 8, a grouting needle 9, a grouting rotating roller 10, a needle rotating clamp 11, a needle receiving clamp 12, and a winding roller 13; the first web tire unwinding roller 1, the laying roller 2, and the second web tire unwinding roller 3 are arranged on the same frame and are installed in a vertically staggered manner, and the unit layer pre-pressing roller 4 is placed at the rear end of the first web tire unwinding roller 1, the laying roller 2, and the second web tire unwinding roller 3; a crawler-type needling device 5 is installed behind the unit layer pre-pressing roller 4; the crawler-type needling device 5 comprises a crawler needle plate 6, a special needle 7 and a flat needling device; the flat needling device comprises a needling Moving parts and flat needle plate 8, the acupuncture moving parts include a driving wheel and a driven wheel; the track needle plate 6 and the flat needle plate 8 are arranged with needle holes arranged in a regular pattern, the track needle plate 6 is installed on the driving wheel and the driven wheel, and the acupuncture driving wheel drives the track needle plate 6 to move; the flat needle plate 8 is installed opposite to the track needle plate 6, and the special needles 7 are installed in the needle holes of the track needle plate 6 and the flat needle plate 8 respectively; a hooking device is arranged at the tail end of the crawler type acupuncture device 5, the hooking device includes a hooking needle 9, a hooking rotating roller 10, a needle rotating clamp 11 and a needle receiving clamp 12, the needle rotating clamp 11 clamps the tail end of the hooking needle 9, is installed on the hooking rotating roller 10, and the needle receiving clamp 12 is fixed at the moving path of the hooking needle 9; the winding roller 13 is installed at the tail of the frame, connected to the motor, and can move actively.

[0028] A method for preparing a unit layer of a long and short fiber combination structure comprises the following steps:

[0029] Step 1: According to the unit layer requirements, X layers of multi-angle fiber cloth and Y layers of web tire are respectively rolled up and placed on X+Y unwinding rollers. After unwinding, the fiber cloth layer and the web tire layer are tensioned by the unwinding speed;

[0030] Step 2, the X-layer multi-angle fiber cloth and the Y-layer web tire are passed through a unit layer pre-pressing roller to form a loose unit layer without interlayer connection;

[0031] Step 3, adjusting the spacing and speed of the crawler-type needling device, and adjusting the speeds of the conveyor belt and the winding device to be consistent;

[0032] Step 4: convey the stacked multi-angle fiber cloth and web tire to the crawler needling device, and start the crawler needling device simultaneously. Under the needling action of special long and short needles with hook teeth, the short fibers in the Y-layer web tire are introduced into the X-layer fiber cloth layer, and X+Y units are consolidated into one unit layer;

[0033] Step 5: After reinforcement, the prefabricated unit layer that is consolidated and stable enters the jointing device;

[0034] Step 6: Keep the unwinding rollers and the winding rollers rotating continuously, adjust the rotation mode of the jointing needle, and then repeat the above steps to connect the multiple unit layers with continuous long fibers;

[0035] Step 7: The unit layers after needle suture are collected into a roll by a winding device.

[0036] Specifically, in step 1, the numbers of X and Y are both greater than or equal to 1; the surface density of the fiber cloth layer and the web layer can be adjusted at will according to the design of the unit layer structure.

[0037] Specifically, the mesh layer includes a mesh formed by various glass fibers such as carbon fiber mesh, quartz fiber mesh or alumina fiber mesh; the multi-angle fiber cloth layer includes a fiber cloth layer formed by various glass fibers such as carbon fiber cloth, quartz fiber cloth or alumina fiber cloth; the multi-angle fiber cloth layer includes satin cloth, spread cloth and weftless cloth.

[0038] Specifically, in step 2, the unit layer pre-pressing roller used for the web layer is in a weak pressure state of 0-5N to keep the web layer in a fluffy state.

[0039] Specifically, in step 3, the conveyor belt rotation speed is coordinated with the grouting action in the grouting device, and there is a pause during the grouting process, and the grouting needle continues to move after exiting the fabric.

[0040] Specifically, in step 4, the spacing between the crawler needling devices is greater than or equal to the theoretical thickness value of the preform unit layer.

[0041] Specifically, the hook needle rotation method in step 6 includes the hook needle rotating 180° clockwise first and then rotating 180° counterclockwise, and the conveying device is indirectly paused according to the suturing requirements; or the hook needle rotates 180° clockwise, and the conveying device continuously advances according to the suturing requirements.

[0042] Specifically, the grouting device in step 6 adjusts the conveying speed of the device according to the requirements of unit layers with different volume densities, and can be controlled in accordance with the requirements of stitching dot arrays with different volume densities. The greater the conveying speed, the smaller the stitching dot array density; the grouting device adjusts the spacing between the hook needle and the unit layer according to the stitching dot array. The larger the stitching spacing, the larger the spacing between the hook needle and the unit layer; the tail end of the grouting device pulls the yarn, and the needle introduces the yarn into the unit layer after passing through the cloth layer.

[0043] Specifically, the preform unit layer in step 7 is in a tensioned state when being rolled up, and the fiber cloth layer and the web layer in the unit layer are consolidated and stable.

[0044] Example 1

[0045] When you need to produce a unit structure "1 layer 80g / m 2 Multi-angle quartz fiber cloth + 1 layer of 150g / m 2When the low-density unit layer of the "quartz fiber mesh tire" is formed, the stitching density is (10×10) mm, and the stitching yarn single strand is 190 tex. The specific implementation method is as follows:

[0046] Step 1: For 80g / m 2 Multi-angle fiber cloth, first place a roll of multi-angle fiber cloth on the first unwinding roller, and realize the flat state transmission of the multi-angle fiber cloth through the unwinding speed.

[0047] Step 2: For 150g / m 2 Quartz fiber mesh tire, first place a roll of quartz fiber mesh tire on the second unwinding roller, and realize the flat state transmission of the quartz fiber mesh tire through the active unwinding speed.

[0048] Step 3: For 80g / m 2 Multi-angle fiber cloth, first place a roll of multi-angle fiber cloth on the third unwinding roller, and realize the flat state transmission of the multi-angle fiber cloth through the unwinding speed.

[0049] Step 4: For 150g / m 2 Quartz fiber mesh tire, first place a roll of quartz fiber mesh tire on the fourth unwinding roller, and realize the flat state transmission of the quartz fiber mesh tire through the active unwinding speed.

[0050] Step 5: Adjust the crawler speed and the flat plate needle punching frequency of the laminated unit structure to achieve short fiber consolidation of the unit layer;

[0051] Step 6: The unit layer after needle punching is transported to the jointing device via a conveyor belt. The conveyor belt is in a continuous conveying state, and the hook needle continuously rotates 360° to introduce continuous long fibers between the unit layers.

[0052] Step 7: The consolidated unit layer is wound on the paper tube on the surface of the winding device for the next process.

[0053] Example 2

[0054] When you need to produce a unit structure "1 layer 290g / m 2 Multi-angle quartz fiber cloth + 1 layer of 50g / m 2 When the high-density unit layer of the "quartz fiber mesh tire" is used, the stitching density is (10×10) mm, the stitching yarn double strands are 190 tex, and the specific implementation method is as follows:

[0055] Step 1: Target 290g / m 2 Multi-angle fiber cloth, first place a roll of multi-angle fiber cloth on the first unwinding roller, and realize the flat state transmission of the multi-angle fiber cloth through the unwinding speed.

[0056] Step 2: For 50g / m 2Quartz fiber mesh tire, first place a roll of quartz fiber mesh tire on the second unwinding roller, and realize the flat state transmission of the quartz fiber mesh tire through the active unwinding speed.

[0057] Step 3: Target 290g / m 2 Multi-angle fiber cloth, first place a roll of multi-angle fiber cloth on the third unwinding roller, and realize the flat state transmission of the multi-angle fiber cloth through the unwinding speed.

[0058] Step 4: For 50g / m 2 Quartz fiber mesh tire, first place a roll of quartz fiber mesh tire on the fourth unwinding roller, and realize the flat state transmission of the quartz fiber mesh tire through the active unwinding speed.

[0059] Step 5: Adjust the crawler speed and the flat plate needle punching frequency of the laminated unit structure to achieve short fiber consolidation of the unit layer;

[0060] Step 6: The unit layer after needle punching is transported to the jointing device via a conveyor belt. The conveyor belt is in a continuous conveying state. The hook needle rotates 180° clockwise and then 180° counterclockwise to introduce continuous long fibers between the unit layers.

[0061] Step 7: The consolidated unit layer is wound on the paper tube on the surface of the winding device for the next process.

[0062] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0063] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A device for preparing a unit layer of a long and short fiber combination structure, characterized in that: The invention comprises a first web tire unwinding roller (1), a laying roller (2), a second web tire unwinding roller (3), a unit layer pre-pressing roller (4), a crawler type needling device (5), a crawler needle plate (6), a special needle (7), a flat needle plate (8), a grouting needle (9), a grouting rotating roller (10), a needle rotating clamp (11), a needle receiving clamp (12), and a winding roller (13); the first web tire unwinding roller (1), the laying roller (2), and the second web tire unwinding roller (3) are arranged on the same frame and are installed in a vertically staggered manner; the unit layer pre-pressing roller (4) is placed at the rear end of the first web tire unwinding roller (1), the laying roller (2), and the second web tire unwinding roller (3); the crawler type needling device (5) is installed behind the unit layer pre-pressing roller (4); the crawler type needling device (5) comprises a crawler needle plate (6), a special needle (7), and a flat needling device; the flat needling device comprises a needling moving part and a flat needling device; The track needle plate (8) comprises a driving wheel and a driven wheel; needle holes arranged in a regular pattern are arranged on the track needle plate (6) and the flat needle plate (8); the track needle plate (6) is mounted on the driving wheel and the driven wheel, and the acupuncture driving wheel drives the track needle plate (6) to move; the flat needle plate (8) is mounted opposite to the track needle plate (6), and the special needles (7) are respectively mounted in the needle holes of the track needle plate (6) and the flat needle plate (8); a hooking device is arranged at the tail end of the track-type needling device (5), and the hooking device comprises a hooking needle (9), a hooking rotating roller (10), a needle rotating clamp (11) and a needle receiving clamp (12); the needle rotating clamp (11) clamps the tail end of the hooking needle (9) and is mounted on the hooking rotating roller (10); the needle receiving clamp (12) is fixedly located at the moving path of the hooking needle (9); the winding roller (13) is mounted at the tail end of the frame, connected to the motor, and can move actively.

2. A method for preparing a unit layer of a long and short fiber combination structure, the method is based on the method for preparing a unit layer of a long and short fiber combination structure according to claim 1, and the method is characterized in that: The following steps are involved: Step 1: According to the unit layer requirements, X layers of multi-angle fiber cloth and Y layers of web tire are respectively rolled up and placed on X+Y unwinding rollers. After unwinding, the fiber cloth layer and the web tire layer are tensioned by the unwinding speed; Step 2, the X-layer multi-angle fiber cloth and the Y-layer web tire are passed through a unit layer pre-pressing roller to form a loose unit layer without interlayer connection; Step 3, adjusting the spacing and speed of the crawler-type needling device, and adjusting the speeds of the conveyor belt and the winding device to be consistent; Step 4: convey the stacked multi-angle fiber cloth and web tire to the crawler needling device, and start the crawler needling device simultaneously. Under the needling action of special long and short needles with hook teeth, the short fibers in the Y-layer web tire are introduced into the X-layer fiber cloth layer, and X+Y units are consolidated into one unit layer; Step 5: After reinforcement, the prefabricated unit layer that is consolidated and stable enters the jointing device; Step 6: Keep the unwinding rollers and the winding rollers rotating continuously, adjust the rotation mode of the jointing needle, and then repeat the above steps to connect the multiple unit layers with continuous long fibers; Step 7: The unit layers after needle suture are collected into a roll by a winding device.

3. The method for preparing a unit layer of a long and short fiber combination structure according to claim 2, characterized in that: In step 1, the numbers of X and Y are both greater than or equal to 1; the surface density of the fiber cloth layer and the web layer can be adjusted arbitrarily according to the design of the unit layer structure.

4. The method for preparing a unit layer of a long and short fiber combination structure according to claim 2 or 3, characterized in that: The mesh layer includes a mesh formed by various glass fibers such as carbon fiber mesh, quartz fiber mesh or alumina fiber mesh; the multi-angle fiber cloth layer includes a fiber cloth layer formed by various glass fibers such as carbon fiber cloth, quartz fiber cloth or alumina fiber cloth; the multi-angle fiber cloth layer includes satin cloth, spread cloth and weftless cloth.

5. The method for preparing a unit layer of a long and short fiber combination structure according to claim 2, characterized in that: In step 2, the unit layer pre-pressing roller used for the web layer is in a weak pressure state of 0-5N to keep the web layer in a fluffy state.

6. The method for preparing a unit layer of a long and short fiber combination structure according to claim 2, characterized in that: In step 3, the conveyor belt speed is coordinated with the grouting action in the grouting device, and there is a pause during the grouting process, and the grouting needle continues to move after exiting the fabric.

7. The method for preparing a unit layer of a long and short fiber combination structure according to claim 2, characterized in that: In step 4, the spacing between the crawler needle punching devices is greater than or equal to the theoretical thickness value of the preform unit layer.

8. The method for preparing a unit layer of a long and short fiber combination structure according to claim 2, characterized in that: The hook needle rotation method in step 6 includes the hook needle rotating 180° clockwise first and then rotating 180° counterclockwise, and the conveying device is indirectly paused according to the suturing requirements; or the hook needle rotates 180° clockwise, and the conveying device continuously advances according to the suturing requirements.

9. The method for preparing a unit layer of a long and short fiber combination structure according to claim 2, characterized in that: The grouting device in step 6 adjusts the conveying speed of the device according to the requirements of unit layers with different volume densities, and can be controlled in accordance with the requirements of stitching dot arrays with different volume densities. The greater the conveying speed, the smaller the stitching dot array density; the grouting device adjusts the spacing between the hook needle and the unit layer according to the stitching dot array. The larger the stitching spacing, the larger the spacing between the hook needle and the unit layer; the tail end of the grouting device pulls the yarn, and the needle introduces the yarn into the unit layer after passing through the cloth layer.

10. The method for preparing a unit layer of a long and short fiber combination structure according to claim 2, characterized in that: The preform unit layer in step 7 is in a tensioned state when being rolled up, and the fiber cloth layer and the web layer in the unit layer are consolidated and stable.

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