Axial Composite Fiber Tube Forming Device and Process Based on Corrugated Sawtooth Splicing

Abstract

This invention discloses an axial composite fiber pipe forming device and process based on corrugated sawtooth splicing, belonging to the field of composite fiber pipe forming technology. The material is cut into interlocking corrugated sawtooth profiles using a cutting platform. These profiles are then aligned using negative pressure adsorption and stitched together using module trajectories to prepare an integrated composite fiber base fabric. The composite base fabric is then wound axially along a mandrel, followed by resin impregnation, curing, and demolding processes to form a coaxial double-layer composite pipe, creating a composite structure with a glass fiber insulating outer layer and a high-strength carbon fiber inner layer. This invention employs a corrugated sawtooth splicing structure, effectively dispersing axial stress, improving interlayer bonding strength and structural integrity, and is compatible with both dry and wet winding processes, offering high precision automated forming. This invention balances the overall insulation performance and high axial strength of the pipe, making it suitable for special high-strength insulation pipeline applications such as high-voltage protection and live-line work, with a stable structure and long service life.

Description

Technical Field

[0001] This invention belongs to the field of composite fiber pipe forming technology, specifically relating to an axial composite fiber pipe forming device and process based on corrugated sawtooth splicing. Background Technology

[0002] Fiberglass pipes possess excellent electrical insulation properties, corrosion resistance, and lightweight characteristics, making them widely used in insulation applications such as electrical insulation, high-voltage protection, and special pipeline installation. However, fiberglass itself has poor mechanical strength, axial tensile strength, and structural rigidity. Pure fiberglass pipes have low pressure resistance and weak bending resistance, making them unsuitable for special operating conditions involving high loads, long spans, and high stress.

[0003] Carbon fiber tubing has outstanding advantages such as high specific strength, high modulus, excellent axial load-bearing capacity, and good structural stability, which can significantly improve the overall mechanical properties of tubing. However, carbon fiber itself has electrical conductivity, and pure carbon fiber tubing does not have insulation capabilities, so it cannot be used in scenarios with strict insulation requirements such as electrical protection, high voltage insulation, and pipelines for live environments.

[0004] In existing technologies, conventional composite fiber pipes are mostly formed by straight butt splicing. The stress concentration of such straight splicing joints is on the weak surface of the straight line. When the pipe is subjected to axial force, it is very easy to crack and delaminate along the joint, resulting in poor overall structural integrity. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide an axial composite fiber tube forming device and process based on wave sawtooth splicing. The present invention can take into account the technical pain points of overall electrical insulation performance and high-strength structural performance, and prepare high-strength insulating composite tubes suitable for special working conditions.

[0006] The technical solution adopted by this invention to solve the problems existing in the prior art is: An axial composite fiber tube forming device based on wave-tooth splicing includes a working platform and a material transfer assembly for material transfer and alignment splicing. The working platform includes a cutting platform and a sewing platform arranged in sequence. The cutting platform is equipped with a cutting component that simultaneously cuts the ends of two sets of fiber fabrics to form a wavy profile that can be fitted, which is used to complete the wavy end cutting and pre-positioning of the two pieces of material. The material transfer assembly has the functions of negative pressure adsorption and fixation of materials, spacing adjustment and planar multi-track movement, and is used to transfer two pieces of cut materials to the sewing platform. The sewing platform is equipped with sewing equipment that can work in conjunction with the dynamic trajectory conveying action of the material transfer assembly to perform continuous sewing operations on the wave-shaped splicing seam of two pieces of material, so that two independent fiber fabrics are fixed together into an integrated composite fiber fabric.

[0007] Furthermore, the material transfer assembly includes a material suction component, a first electric linear module, and a second electric linear module; the material suction component is connected to the moving part of the first electric linear module, and the moving parts of the first electric linear module and the second electric linear module are vertically fixedly connected, with the two linear modules linked to form an X and Y axis planar motion coordinate system; the second electric linear module has support legs fixed at both ends for overall support; the material suction component can drive the material to move along a preset wave trajectory, and work with the sewing machine to complete continuous sewing of the wave seam.

[0008] Furthermore, the material suction assembly includes two sets of spaced pressure plates, a T-shaped plate, a guide rod, a double-ended stud, and a servo motor; The bottom of the pressure plate is arrayed with several suction cups that communicate with the internal cavity. The pressure plate is connected to an external air extraction pipe and a vacuum pump to achieve negative pressure adsorption of materials. Each pressure plate has a U-shaped frame fixed on its top surface. The two sets of U-shaped frames are respectively assembled with guide rods and double-ended studs. The two ends of the double-ended studs have reverse threads and are threaded into the two sets of U-shaped frames respectively. The guide rods and the ends of the double-ended studs are rotatably assembled on the T-shaped plate. The servo motor is fixed to the T-shaped plate and its output shaft is connected to the double-ended studs for transmission. It is used to drive the two sets of pressure plates to move towards or away from each other, so as to realize the alignment and splicing of the material wave cut and the adjustment of the spacing.

[0009] Furthermore, the material suction assembly also includes a lifting controller, which adopts two independently implementable assembly structures; The first assembly structure: The lifting controller is fixed to the moving part of the first electric linear module. The telescopic part of the lifting controller is connected to the T-shaped plate. By driving the T-shaped plate to lift as a whole, the pressure plate moves up and down to realize the material pressing and releasing. The second assembly structure: the T-shaped plate is fixedly connected to the first electric linear module, the lifting controller is fixed on the T-shaped plate, the telescopic part of the lifting controller is directly connected to the pressure plate, and a telescopic guide rod is assembled between the pressure plate and the U-shaped frame to realize the independent lifting and positioning of the pressure plate.

[0010] Furthermore, the cutting platform includes two sets of relatively spaced support platforms, support plates, several springs, and connecting plates; the bottom of the opposite ends of the two sets of support platforms are respectively provided with bottom connecting grooves, and the two ends of the connecting plates are engaged in the bottom connecting grooves and locked and fixed by bolts; the opposite end faces of the two sets of support platforms are provided with at least two sets of bottom open limiting slide grooves, and the support plates are provided with sliders protruding from both sides, and the sliders are slidably assembled inside the limiting slide grooves; the springs are sandwiched between the support plates and the connecting plates, and under normal conditions, the springs push the support plates upward so that the top surface of the support plates is flush with the top surface of the support platforms to form a flat bearing surface.

[0011] Furthermore, an abutment strip is fixed on the support platform. The abutment strip is used for lateral positioning when materials are placed to ensure the parallelism and cutting contour accuracy of the materials.

[0012] Furthermore, a cutting assembly is provided above the cutting platform, the cutting assembly including a telescopic controller, a telescopic rod, a cutter head, a mounting plate, and a top rod; The telescopic controller is fixed to the support platform by a bracket. The telescopic controller is connected to the cutter head by a telescopic rod. The bottom of the cutter head is provided with an integral cutting blade formed by splicing two wavy cutting edges. The telescopic controller has a fixed mounting plate at the bottom, and the mounting plate has a vertically fixed top rod. The lower end of the top rod passes through the cutter head and extends into the internal cavity of the cutter head, which is used to automatically eject the scraps after cutting to achieve self-cleaning of the cutter head.

[0013] Furthermore, the sewing platform includes a sewing workbench and a sewing machine, the top surface of the sewing workbench is flush with the top surface of the support platform, and the end of the sewing workbench is abutted and connected to the end of the cutting platform; Both the telescopic controller and the lifting controller use telescopic electric cylinders. All electrical components in the device are electrically connected to the electrical control box and are coordinated and controlled through existing electrical control technology.

[0014] A forming process for axial composite fiber tubing based on corrugated sawtooth splicing includes the following steps: S01. Fiber fabric feeding and wave contour cutting: Two pieces of material, fiberglass cloth and carbon fiber cloth, are placed on the cutting platform. Lateral positioning is achieved by the abutment strip. The lifting controller drives the pressure plate to move down and press the material. The telescopic controller drives the cutter head down and uses the wave-shaped cutter to cut the joint end of the two pieces of material simultaneously, thus processing a wave-shaped contour that can be interlocked. During the cutting process, the cutter head presses down on the support plate, causing the support plate to overcome the spring force and move downward along the limiting groove to ensure that the material is completely cut off; after the cutting is completed, the cutter head moves upward to reset, and the push rod automatically pushes out the cut scraps inside the cutter head to complete the self-cleaning process. S02, Wavy sawtooth edge alignment and pre-assembly: A vacuum pump is used to create a vacuum in the suction cup at the bottom of the pressure plate, and the two pieces of material after cutting are fixed by negative pressure adsorption. The servo motor drives the double-headed stud to rotate, which in turn moves the two sets of pressure plates toward each other, so that the wavy cuts of the two pieces of material fit together and align, forming a flat butt joint or a small overlap to be sewn, thus completing the pre-splicing positioning. S03. Preparation of composite fiber base fabric by continuous stitching of wavy seams: The first electric linear module and the second electric linear module work together to drive the material to be transferred to the sewing platform along a preset trajectory; the material travel trajectory is matched with the sewing machine sewing action to continuously sew the wavy sawtooth seam, and the glass fiber cloth and carbon fiber cloth are fixed together as an integrated axial composite fiber base cloth; inorganic fiber sewing thread is used for sewing, and the seam defects and fabric rough edges are repaired after sewing. S04. Pre-treatment of pipe forming mandrel: Select a cylindrical rigid mandrel and apply a release agent evenly to the outer surface of the mandrel to prevent the subsequent pipe blank from sticking to the mandrel; S05, Composite fiber cloth winding and forming: The end of the composite fiber base fabric is fixed to the surface of the core mold, and spiral or circumferential winding is performed along the axis of the core mold, controlling the winding tension, number of layers and winding angle; it is formed by two methods: dry fabric winding or pre-impregnated fabric winding. After winding, a coaxial double-layer structure is formed, corresponding to the glass fiber tube matrix and the carbon fiber tube matrix respectively. The double-layer matrix achieves continuous transition through wave stitching seams. S06, Resin Impregnation and Compaction Degassing: If dry fabric winding is used, the wound fiber preform is immersed in epoxy resin or vinyl ester resin solution, and the fiber is fully wetted and the internal air is discharged by roller pressing and vacuum guiding. If prepreg winding is used, this step is omitted. S07, Heat curing and molding: The resin-impregnated fiber preform, together with the mandrel, is sent into a curing oven or hot-pressed with an external mold and cured at a constant temperature according to a preset stepped temperature rise curve to cross-link and harden the resin, forming an integrated axial composite fiber tube preform. S08. Demolding and pipe post-processing: After the tube blank has cooled, the mandrel is axially extracted, the two ends of the tube are cut and smoothed, and the defects on the inner and outer surfaces are polished to obtain an axially composite fiber tube with a coaxial composite structure.

[0015] Furthermore, in S03, the stitching adopts a transverse cross-joint arrangement, the stitching is perpendicular to the pipe axis, the stitch spacing is controlled between 3 and 8 mm, and the stitching is denser at the stress concentration positions of the wave crest and trough of the wave joint.

[0016] Compared with the prior art, the present invention has the following beneficial effects: (1) This invention makes full use of the material properties of glass fiber insulation and carbon fiber high strength to form a coaxial double-layer composite pipe structure. The outer layer / insulation layer adopts glass fiber structure to ensure the overall excellent electrical insulation performance of the pipe. The inner layer adopts high-strength carbon fiber structure to greatly improve the axial tensile, compressive and bending resistance of the pipe. It completely solves the industry pain points of low strength of traditional glass fiber pipe and non-insulation of carbon fiber pipe. It is specially adapted to special scenarios such as high voltage protection, live matching, and special industrial insulation pipeline.

[0017] (2) This invention abandons the traditional straight-line splicing method and adopts a wave sawtooth interlocking and continuous stitching process, which greatly extends the stress path of the joint, disperses and deflects the axial stress, avoids stress concentration on a single straight joint, significantly improves the axial crack resistance and interlayer bonding strength of the pipe, eliminates the problems of double-layer pipe peeling, delamination, cracking failure, and greatly improves the overall structure.

[0018] (3) This invention achieves precise fabric positioning, precise cutting, automatic alignment, and continuous trajectory stitching through a dedicated cutting platform, negative pressure adsorption alignment mechanism, and dual-module trajectory collaborative shifting mechanism. The entire process is automated, effectively avoiding problems such as size deviation, splicing misalignment, and uneven stitching caused by manual operation, greatly improving the forming accuracy of composite fabric and ensuring the consistency of the quality of subsequent pipe products.

[0019] (4) This invention is compatible with both dry prepreg winding and wet impregnation winding processes, which can meet different production needs. The double fiber layers form a continuous transition integrated structure through a wave stitching structure. After the resin is cured, the interlayer bonding is tight and there are no obvious weak interfaces. The overall rigidity, fatigue resistance and weather resistance of the pipe are greatly improved, which can meet the long-term stable use requirements of special working conditions. Attached Figure Description

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0021] Figure 1 This is a structural diagram of the axial composite fiber tube forming device based on wave-tooth splicing according to the present invention. Figure 2 This is a side view of the axial composite fiber tube forming device based on corrugated sawtooth splicing according to the present invention. Figure 3 This is a structural diagram of the working platform in the axial composite fiber tube forming device based on wave-tooth splicing of the present invention. Figure 4 This is a structural diagram of the cutting platform in the axial composite fiber tube forming device based on wave-tooth splicing of the present invention. Figure 5 for Figure 4 Structural diagram after material removal. Figure 6 This is a diagram of the bottom structure of the cutting platform. Figure 7 for Figure 6 Structural diagram after removing the connecting plate. Figure 8 This is a structural diagram of the cutting component in the axial composite fiber tube forming device based on wave-tooth splicing of the present invention. Figure 9 This is a structural diagram of the material transfer assembly in the axial composite fiber tube forming device based on wave-tooth splicing of the present invention. Figure 10 This is a structural diagram of the material attraction component. Figure 11 This is a schematic diagram of the bottom of the material suction assembly.

[0022] In the diagram: 1-Support platform, 101-Bottom connecting groove, 102-Limiting slide, 103-Abutting strip, 2-Support plate, 201-Slider, 3-Spring, 4-Connecting plate, 5-Cutting assembly, 501-Telescopic controller, 502-Telescopic rod, 503-Cutter head, 504-Mounting plate, 505-Top rod, 6-Sewing workbench, 7-Sewing machine, 8-Material suction assembly, 801-Pressure plate, 802-Suction cup, 803-U-shaped frame, 804-T-shaped plate, 805-Guide rod, 806-Double-headed stud, 807-Servo motor, 808-Lifting controller, 9-First electric linear module, 10-Second electric linear module, 11-Support leg, 12-Material. Detailed Implementation

[0023] The accompanying drawings provide a more detailed description of the axial composite fiber tube forming device and process based on wave-tooth splicing of the present invention, but this is not intended to limit the scope of the invention.

[0024] Depend on Figure 1 as well as Figure 2 As shown, an axial composite fiber tube forming device based on wavy sawtooth splicing includes a working platform and a material transfer assembly. The working platform consists of a cutting platform and a sewing platform. The cutting platform is used to cut the connecting ends of two oppositely arranged materials 12 to form a wavy profile that can be interlocked and spliced ​​together, so as to complete the pre-splicing of the two materials 12. After cutting and preliminary splicing and positioning, the material transfer assembly transfers the material 12 as a whole to the sewing platform. The sewing machine 7 configured on the sewing platform performs continuous sewing on the splicing seam of the two materials 12, so that the glass fiber cloth and carbon fiber cloth are fixed together into a complete composite fiber fabric. In this embodiment, the two materials 12 are glass fiber cloth and carbon fiber cloth that have not undergone resin curing treatment.

[0025] Depend on Figure 9As shown, the material transfer assembly includes a material suction component 8, a first electric linear module 9, and a second electric linear module 10. The material suction component 8 is used to independently suction and position two pieces of material 12. The material suction component 8 is connected to the moving part of the first electric linear module 9, and the first electric linear module 9 is fixedly connected to the moving part of the second electric linear module 10. The first electric linear module 9 and the second electric linear module 10 are arranged perpendicularly to each other, and the movement trajectories of the moving parts of the two modules together form an X and Y axis plane coordinate system. Relying on the linkage control of the two sets of linear modules, the material suction component 8 can drive the two pieces of material 12 to achieve arbitrary trajectory movement in the plane coordinate system. Furthermore, through the coordinated matching of the sewing action of the sewing machine 7 and the walking trajectory of the material transfer assembly by the control system, the splicing area of ​​the two pieces of material 12 to be sewn passes through the sewing area of ​​the sewing machine 7 at a uniform speed along a wave-shaped walking trajectory, cooperating with the sewing machine 7 to continuously complete the overall sewing operation at the wave seam of the two pieces of material 12, and finally achieving a stable connection between the fiberglass cloth and the carbon fiber cloth. The two ends of the second electric linear module 10 are fixedly supported by support legs 11 to ensure the structural stability of the entire displacement mechanism during operation.

[0026] Depend on Figure 10 as well as Figure 11 As shown, the material suction assembly 8 includes two spaced-apart pressure plates 801 and a T-shaped plate 804. Several suction cups 802 are installed at the bottom of the pressure plates 801, and the suction cups 802 communicate with the internal cavity of the pressure plates 801. An air extraction pipe connected to the internal cavity of the pressure plates 801 is provided, and a vacuum pump is connected to the external air extraction pipe to achieve flat suction of the material 12 by relying on negative pressure. Two U-shaped frames 803 are vertically and fixedly installed at intervals on the top surface of the pressure plates 801. One U-shaped frame 803 has a through hole on its top horizontal rod, through which a guide rod 805 that can slide relative to it passes. The other U-shaped frame 803 has a threaded hole on its top horizontal rod, through which a threaded double-ended stud 806 passes. The two threaded sections of the double-ended stud 806 rotate in opposite directions, and the two threads respectively form a threaded engagement with the threaded holes of the U-shaped frames 803 arranged oppositely on the two pressure plates 801.

[0027] The guide rod 805 and the double-ended stud 806 are respectively arranged on both sides of the T-shaped plate 804. The ends of the guide rod 805 and the double-ended stud 806 are inserted into the through holes of the T-shaped plate 804 and form a rotational fit. A servo motor 807 is fixedly installed on the T-shaped plate 804, and the output shaft of the servo motor 807 is connected to the double-ended stud 806 for transmission. When the servo motor 807 drives the double-ended stud 806 to rotate forward or backward, the two sets of pressure plates 801 are driven to move towards each other synchronously or away from each other by means of the positive and negative threads, so as to realize the alignment and splicing and spacing adjustment of the wavy cuts of the two pieces of material 12.

[0028] To achieve clamping and fixing during the material 12 cutting process and prevent the fiber fabric from slipping and the cut from misaligning, in this embodiment, the material suction assembly 8 also includes a lifting controller 808. The lifting controller 808 can be arranged in two independently implementable ways: Arrangement Method 1: The lifting controller 808 is fixedly connected to the moving part of the first electric linear module 9, and the telescopic part of the lifting controller 808 is connected to the T-shaped plate 804. The lifting controller 808 drives the T-shaped plate 804 to lift as a whole, and synchronously drives the pressure plate 801 to move up and down, so as to realize the pressing contact and release of the pressure plate 801 on the material 12, and complete the material clamping and positioning before cutting.

[0029] Arrangement Method Two: The T-shaped plate 804 is fixedly connected to the first electric linear module 9, and the lifting controller 808 is fixedly mounted on the T-shaped plate 804. The telescopic part of the lifting controller 808 is directly connected to the pressure plate 801, and a telescopic guide rod is installed between the pressure plate 801 and the U-shaped frame 803. The lifting controller 808 independently drives the pressure plate 801 to lift up and down independently, realizing the pressing, fixing and releasing action of the material 12.

[0030] Depend on Figures 4 to 7 As shown, the cutting platform includes two support platforms 1 arranged at relative intervals, a support plate 2, a spring 3, and a connecting plate 4. The bottom surfaces of the two support platforms 1, which are close to each other, are recessed inward with bottom connecting grooves 101. The two ends of the connecting plate 4 are respectively inserted into the two bottom connecting grooves 101, and the two support platforms 1 and the connecting plate 4 are locked and fixed with bolts to form the basic frame of the cutting platform.

[0031] At least two sets of parallel, spaced-apart limiting grooves 102 are recessed on the opposite end faces of the two support platforms 1, with only the bottom of the limiting grooves 102 open. The support plate 2 is mounted between the two support platforms 1, and a slider 201 protrudes outward from the bottom of the support plate 2, which is slidably fitted inside the limiting groove 102. Several springs 3 are installed between the support plate 2 and the connecting plate 4. Under the upward pushing force of the springs 3, the slider 201 normally slides to the uppermost position of the limiting groove 102, at which point the top surface of the support plate 2 is flush with the top surfaces of the two support platforms 1, forming a flat material bearing surface.

[0032] The support platform 1 is equipped with an abutment strip 103. When the material 12 is placed and fed, the side of the material and the abutment strip 103 fit together and limit each other, thereby ensuring the parallelism of the material 12 and preventing the fabric from being skewed and causing deviation in the cutting outline.

[0033] The cutting component 5 is positioned above the support plate 2. Figure 8As shown, the cutting assembly 5 includes a telescopic controller 501, a cutter head 503, and a top rod 505. The telescopic controller 501 is connected to the cutter head 503 via a vertically arranged telescopic rod 502, with the cutter head 503 facing downwards. The cutter head's cutting edge is formed by two wavy cutting edges spliced ​​together to create a complete cutting contour. This special cutting edge structure allows for simultaneous cutting of the ends of two pieces of material 12. After the material is cut, simply moving the two pieces of material 12 relative to each other allows the two sets of wavy cuts to interlock seamlessly.

[0034] The telescopic controller 501 is fixedly connected to the support platform 1 via a bracket. A mounting plate 504 is fixedly installed on the bottom of the telescopic controller 501, and a top rod 505 is vertically fixed to the lower end of the mounting plate 504. The lower end of the top rod 505 passes through a pre-set through hole on the cutter head 503 and extends into the internal cavity of the cutter head 503.

[0035] In this embodiment, both the telescopic controller 501 and the lifting controller 808 can be electrically driven components, specifically telescopic electric cylinders. All electrical components in this device are electrically connected to the electrical control box, and the composition, connection method, and control method of the electrical control box all adopt existing technologies.

[0036] The sewing platform includes a sewing workbench 6 and a sewing machine 7. The top surface of the sewing workbench 6 is flush with the top surface of the support platform 1. The ends of the sewing workbench 6 and the ends of the cutting platform abut against each other, which facilitates the smooth transfer of materials and eliminates the bending and deformation of the fabric caused by height difference.

[0037] At the start of the operation, the operator places two pieces of material 12 on the cutting platform's support surface. Then, the lifting controller 808 drives the pressure plate 801 downwards to press down on the material 12, restricting its free movement. Subsequently, the telescopic controller 501 drives the telescopic rod 502 to extend, causing the cutter head 503 to move downwards and simultaneously cut the adjacent connecting ends of the two pieces of material 12. During the cutting process, the cutter head 503 continuously presses down on the support plate 2. The support plate 2 overcomes the elastic force of the spring 3 and slides downwards along the limiting groove 102, creating a clearance space to ensure that the material 12 can be completely cut. Because the material 12 is pre-pressed and limited by the pressure plate 801, even if the support plate 2 retracts downwards, the material cut remains smooth and the cutting dimensions are accurate.

[0038] After the material cutting process is completed, the telescopic controller 501 drives the cutter head 503 to return to its original position. Since the push rod 505 is fixed on the mounting plate 504 and its position remains unchanged, during the upward lifting of the cutter head 503, the push rod 505 extends into the cutter head cavity and automatically pushes out the cutting scraps trapped inside the cutter head downward, realizing self-cleaning of the cutter head and avoiding the accumulation of scraps that may affect the subsequent cutting accuracy.

[0039] After cutting and material arrangement, the vacuum pump is started and a vacuum is drawn into the inner cavity of the suction cup 802 through the suction pipe. The negative pressure stably adsorbs the two pieces of material 12 under the corresponding pressure plate 801. Then, the servo motor 807 starts and drives the double-ended stud 806 to rotate. The positive and negative thread structure of the double-ended stud drives the two pressure plates 801 to move towards each other, so that the wavy cut ends of the two pieces of material 12 interlock to complete the pre-splicing. After the splicing and positioning is completed, the first electric linear module 9 and the second electric linear module 10 work together to drive the material 12 in the adsorbed and fixed state to move at a constant speed according to the preset wavy trajectory. This allows the splicing seam to continuously pass through the sewing needle position of the sewing machine 7. The sewing machine 7 completes the stitching process of the entire wavy seam, and finally, an integrated wavy sawtooth spliced ​​composite fiber cloth is obtained, which provides qualified blanks for the subsequent winding and preparation of axial composite fiber tubes.

[0040] A forming process for axial composite fiber tubing based on corrugated sawtooth splicing includes the following steps: S01. Fiber fabric feeding and wave contour cutting: Two pieces of material 12, fiberglass cloth and carbon fiber cloth, are placed on the cutting platform of the forming device, respectively. The abutment strip 103 on the support table 1 provides lateral positioning of the fabric. The lifting controller 808 drives the pressure plate 801 to move down and press the material 12 to prevent the fabric from slipping during the cutting process. Then, the telescopic controller 501 drives the telescopic rod 502 to move the cutter head 503 down. The wavy blade at the lower end of the cutter head 503 simultaneously cuts the connecting ends of the fiberglass cloth and carbon fiber cloth, creating a wavy profile at the ends of the two pieces of material 12 that can fit together. During cutting, the cutter head 503 presses down on the support plate 2, and the support plate 2 overcomes the elasticity of the spring 3 and moves down along the limiting groove 102 to ensure that the fabric is completely cut. After cutting, the cutter head 503 moves up to reset, and the fixed-position top rod 505 pushes out the cutting debris retained in the cutter head 503, completing the self-cleaning of the cutter head.

[0041] S02, Wavy sawtooth edge alignment and pre-assembly The vacuum pump operates, drawing a vacuum through the suction cup 802 at the bottom of the pressure plate 801 via the suction pipe. The negative pressure then adsorbs and fixes the cut glass fiber cloth and carbon fiber cloth under the two pressure plates 801 respectively. The servo motor 807 drives the double-ended stud 806 to rotate, and the positive and negative threads cause the two pressure plates 801 to move towards each other, so that the wavy cuts at the ends of the glass fiber cloth and carbon fiber cloth interlock and align, forming a flat butt joint or a small overlap to be sewn, thus completing the pre-splicing and positioning of the two materials 12.

[0042] S03. Continuous stitching of wave-shaped seams to prepare composite fiber base fabric. The material transfer assembly is activated, and the first electric linear module 9 and the second electric linear module 10, arranged perpendicularly to each other, move in tandem to transport the material 12 in an adsorbed state along a preset trajectory to the sewing platform. The control system coordinates and matches the material's travel path with the sewing action of the sewing machine 7, ensuring that the wavy seam of the two pieces of material 12 passes through the sewing area of ​​the sewing machine 7 at a uniform speed along the planned path, completing continuous sewing along the wavy sawtooth seam, connecting the fiberglass cloth and carbon fiber cloth into a single axial composite fiber base fabric. The sewing stitches are arranged horizontally across the seam, perpendicular to the tube axis, with a stitch spacing controlled between 3 and 8 mm, and the stitches are denser at the stress concentration points of the wavy seam's crests and troughs. Inorganic fiber sewing thread is used as the sewing material. After sewing, the seam is inspected for broken threads, bulges, gaps, and other defects, and the rough edges of the fabric are trimmed.

[0043] S04. Pre-treatment of pipe forming core mold A cylindrical rigid mandrel is selected as the molding base, and the outer diameter of the mandrel determines the inner diameter of the composite pipe. A release agent is evenly applied to the outer surface of the mandrel to prevent the pipe blank from sticking to the mandrel after subsequent curing.

[0044] S05, Composite fiber cloth wound molding The starting end of the sewn axial composite fiber base fabric is fixed to the surface of the pretreated mandrel, and a spiral or circumferential overlay winding operation is performed along the mandrel axis. The winding tension, total number of winding layers, and fiber winding angle are precisely controlled during the production process. The process employs one of the following two implementation methods: Method 1: Use dry composite fiber cloth for winding, and carry out resin impregnation process uniformly after winding.

[0045] Method 2: Pre-impregnate the composite fiber base fabric with resin to make a pre-impregnated fabric, and then directly use the pre-impregnated fabric to complete the winding.

[0046] After winding, a coaxial double-layer structure is naturally formed. The glass fiber area on the base fabric is wound to form the glass fiber tube matrix, and the carbon fiber area is wound to form the carbon fiber tube matrix. The glass fiber tube matrix and the carbon fiber tube matrix are continuously transitioned through multi-layer wavy stitching joints.

[0047] S06, Resin Impregnation and Compaction Degassing When S05 uses the dry fabric winding method (Method 1), this step is performed: the wound fiber preform is immersed entirely in epoxy resin or vinyl ester resin solution, and the resin is fully impregnated with the fiber fabric through a combination of roller pressing and vacuum diversion, while simultaneously expelling the air trapped between the fabric layers to avoid air bubbles and delamination defects inside the finished product. If prepreg dry winding is used, this step is omitted.

[0048] S07, Heat curing molding The resin-impregnated fiber winding preform, along with the mandrel, is fed into a heating and curing oven, or hot-pressed using an outer mold. A constant-temperature curing process is then performed according to a preset stepped heating curve to promote full cross-linking and hardening of the resin, resulting in an integrated axial composite fiber tube preform.

[0049] S08, Demolding and Pipe Post-processing After the tube blank has cooled sufficiently, the internal rigid mandrel is extracted axially. Excess fabric at both ends of the tube is trimmed and smoothed, and burrs and defects on the inner and outer surfaces of the tube are ground off to obtain a finished axially composite fiber tube made of coaxially arranged glass fiber tubes and carbon fiber tubes.

[0050] S09, Finished Product Performance Testing The finished pipes are subjected to dimensional and mechanical property tests, including the outer diameter, wall thickness, axial tensile strength, and interlaminar shear strength. After passing the inspection, they are put into storage.

[0051] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. An axial composite fiber tube forming device based on corrugated sawtooth splicing, characterized in that: This includes a work platform and a material transfer assembly for material handling and alignment. The working platform includes a cutting platform and a sewing platform arranged in sequence. The cutting platform is equipped with a cutting component that simultaneously cuts the ends of two sets of fiber fabrics to form a wavy profile that can be fitted, which is used to complete the wavy end cutting and pre-positioning of the two pieces of material. The material transfer assembly has the functions of negative pressure adsorption and fixation of materials, spacing adjustment and planar multi-track movement, and is used to transfer two pieces of cut materials to the sewing platform. The sewing platform is equipped with sewing equipment that can work in conjunction with the dynamic trajectory conveying action of the material transfer assembly to perform continuous sewing operations on the wave-shaped splicing seam of two pieces of material, so that two independent fiber fabrics are fixed together into an integrated composite fiber fabric.

2. The axial composite fiber tube forming device based on corrugated sawtooth splicing according to claim 1, characterized in that: The material transfer assembly includes a material suction component (8), a first electric linear module (9), and a second electric linear module (10). The material suction component (8) is connected to the moving part of the first electric linear module (9), and the moving parts of the first electric linear module (9) and the second electric linear module (10) are vertically fixedly connected. The two linear modules work together to form an X and Y axis planar motion coordinate system. The second electric linear module (10) has support legs (11) fixed at both ends for overall support. The material suction component (8) can drive the material to move along a preset wave trajectory and work with the sewing machine (7) to complete the continuous stitching of the wave seam.

3. The axial composite fiber tube forming device based on corrugated sawtooth splicing according to claim 2, characterized in that: The material suction assembly (8) includes two sets of spaced pressure plates (801), a T-shaped plate (804), a guide rod (805), a double-headed stud (806), and a servo motor (807). The bottom of the pressure plate (801) is provided with several suction cups (802) that communicate with the internal cavity. The pressure plate (801) is connected to an external suction pipe and a vacuum pump to achieve negative pressure adsorption of materials. Each pressure plate (801) has a U-shaped frame (803) fixed on its top surface. The two sets of U-shaped frames (803) are respectively assembled with guide rods (805) and double-headed studs (806). The two ends of the double-headed studs (806) have reverse thread structures and are threadedly engaged with the two sets of U-shaped frames (803). The guide rods (805) and the ends of the double-headed studs (806) are rotatably assembled on T-shaped plates (804). The servo motor (807) is fixed on the T-shaped plate (804) and its output shaft is connected to the double-headed studs (806) for transmission. It is used to drive the two sets of pressure plates (801) to move towards or away from each other, so as to realize the alignment and splicing of the material wave cut and the adjustment of the spacing.

4. The axial composite fiber tube forming device based on corrugated sawtooth splicing according to claim 3, characterized in that: The material suction assembly (8) also includes a lifting controller (808), which adopts two independently implementable assembly structures; The first assembly structure: The lifting controller (808) is fixed to the moving part of the first electric linear module (9). The telescopic part of the lifting controller (808) is connected to the T-shaped plate (804). By driving the T-shaped plate (804) to lift as a whole, the pressure plate (801) moves up and down to realize the pressing and releasing of materials. The second assembly structure: the T-shaped plate (804) is fixedly connected to the first electric linear module (9), the lifting controller (808) is fixed on the T-shaped plate (804), the telescopic part of the lifting controller (808) is directly connected to the pressure plate (801), and a telescopic guide rod is assembled between the pressure plate (801) and the U-shaped frame (803) to realize the independent lifting and positioning of the pressure plate (801).

5. The axial composite fiber tube forming device based on corrugated sawtooth splicing according to claim 1, characterized in that: The cutting platform includes two sets of support platforms (1) arranged at relative intervals, a support plate (2), several springs (3) and a connecting plate (4); the bottom of the opposite ends of the two sets of support platforms (1) are respectively provided with bottom connecting grooves (101), and the two ends of the connecting plate (4) are engaged in the bottom connecting grooves (101) and locked and fixed by bolts; the opposite end faces of the two sets of support platforms (1) are provided with at least two sets of bottom open limiting slide grooves (102), and the two sides of the support plate (2) are provided with sliders (201), and the sliders (201) are slidably assembled in the limiting slide grooves (102); the springs (3) are sandwiched between the support plate (2) and the connecting plate (4), and under normal conditions, the springs (3) push the support plate (2) upward, so that the top surface of the support plate (2) is flush with the top surface of the support platform (1) to form a flat bearing surface.

6. The axial composite fiber tube forming device based on corrugated sawtooth splicing according to claim 5, characterized in that: A retaining strip (103) is fixed on the support platform (1). The retaining strip (103) is used for lateral positioning when the material is placed to ensure the parallelism of the material cutting and the accuracy of the cutting outline.

7. The axial composite fiber tube forming device based on corrugated sawtooth splicing according to claim 5, characterized in that: A cutting assembly (5) is provided above the cutting platform. The cutting assembly (5) includes a telescopic controller (501), a telescopic rod (502), a cutter head (503), a mounting plate (504), and a top rod (505). The telescopic controller (501) is fixed to the support platform (1) by a bracket. The telescopic controller (501) is connected to the cutter head (503) by a telescopic rod (502). The bottom of the cutter head (503) is provided with an integral cutting blade formed by splicing two wavy cutting edges. The telescopic controller (501) is fixed to the bottom of the mounting plate (504), and the mounting plate (504) is vertically fixed to the top rod (505). The lower end of the top rod (505) passes through the cutter head (503) and extends into the internal cavity of the cutter head (503) for automatically ejecting the scrap material after cutting to achieve self-cleaning of the cutter head.

8. The axial composite fiber tube forming device based on corrugated sawtooth splicing according to claim 1, characterized in that: The sewing platform includes a sewing workbench (6) and a sewing machine (7). The top surface of the sewing workbench (6) is flush with the top surface of the support platform (1), and the end of the sewing workbench (6) is connected to the end of the cutting platform. Both the telescopic controller (501) and the lifting controller (808) adopt telescopic electric cylinders. All electrical components in the device are electrically connected to the electrical control box and achieve coordinated control through existing electrical control technology.

9. A forming process for axial composite fiber tubes based on corrugated sawtooth splicing, characterized in that, Includes the following steps: S01. Fiber fabric feeding and wave contour cutting: Two pieces of material (12), glass fiber cloth and carbon fiber cloth, are placed on the cutting platform respectively. Lateral limiting is achieved by the abutment strip (103). The lifting controller (808) drives the pressure plate (801) to move down and press the material (12). The telescopic controller (501) drives the cutter head (503) to move down and uses the wave-shaped cutter to cut the joint end of the two pieces of material (12) simultaneously, and process a wave-shaped contour that can be interlocked. During the cutting process, the cutter head (503) presses down on the support plate (2), causing the support plate (2) to overcome the elastic force of the spring (3) and move downward along the limiting slide groove (102) to ensure that the material is completely cut off; after the cutting is completed, the cutter head (503) moves upward to reset, and the push rod (505) automatically pushes out the cutter head (503) to cut the scraps inside, completing the self-cleaning process; S02, Wavy sawtooth edge alignment and pre-assembly: The vacuum pump is used to evacuate the suction cup (802) at the bottom of the pressure plate (801), and the negative pressure adsorbs and fixes the two pieces of material (12) after cutting. The servo motor (807) drives the double-headed stud (806) to rotate, which drives the two sets of pressure plates (801) to move towards each other, so that the wavy cuts of the two pieces of material (12) are interlocked and aligned to form a flat butt joint or a small overlap to be sewn, thus completing the pre-splicing positioning. S03. Preparation of composite fiber base fabric by continuous stitching of wavy seams: The first electric linear module (9) and the second electric linear module (10) are linked together to drive the material (12) to be transferred to the sewing platform according to the preset trajectory; the material walking trajectory is matched with the sewing action of the sewing machine (7) to continuously sew the wavy sawtooth seam, and the glass fiber cloth and carbon fiber cloth are fixed together as an integrated axial composite fiber base cloth; inorganic fiber sewing thread is used for sewing, and the seam defects and fabric rough edges are repaired after sewing; S04. Pre-treatment of pipe forming mandrel: Select a cylindrical rigid mandrel and apply a release agent evenly to the outer surface of the mandrel to prevent the subsequent pipe blank from sticking to the mandrel; S05, Composite fiber cloth winding and forming: The end of the composite fiber base fabric is fixed to the surface of the core mold, and spiral or circumferential winding is performed along the axis of the core mold, controlling the winding tension, number of layers and winding angle; it is formed by two methods: dry fabric winding or pre-impregnated fabric winding. After winding, a coaxial double-layer structure is formed, corresponding to the glass fiber tube matrix and the carbon fiber tube matrix respectively. The double-layer matrix achieves continuous transition through wave stitching seams. S06, Resin Impregnation and Compaction Degassing If dry fabric winding is used, the wound fiber preform is immersed in epoxy resin or vinyl ester resin solution, and the fiber is fully wetted and the internal air is discharged by roller pressing and vacuum guiding. If prepreg winding is used, this step is omitted. S07, Heat curing and molding: The resin-impregnated fiber preform, together with the mandrel, is sent into a curing oven or hot-pressed with an external mold and cured at a constant temperature according to a preset stepped temperature rise curve to cross-link and harden the resin, forming an integrated axial composite fiber tube preform. S08. Demolding and pipe post-processing: After the tube blank cools, the mandrel is axially extracted, the two ends of the tube are cut and smoothed, and the defects on the inner and outer surfaces are polished to obtain an axially composite fiber tube with a coaxial composite structure.

10. The axial composite fiber tube forming process based on corrugated sawtooth splicing according to claim 9, characterized in that: In S03, the stitching adopts a transverse cross-joint arrangement, the stitching is perpendicular to the pipe axis, the stitch spacing is controlled between 3 and 8 mm, and the stitching is denser at the stress concentration positions of the wave crest and trough of the wave joint.

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