A rotary preform needling robot with integrated automatic feeding and a preparation method thereof

Abstract

The present application relates to a kind of integrated automatic feeding rotary preform needle punching robot, the robot includes industrial robot, robot base, end effector, workbench, T-shaped workbench and orthogonal reference limit component;Workbench includes rotary workbench, rotary workbench base, adapter flange and core mold;End effector is installed at the end of industrial robot, integrated with needle punching mechanism and the pneumatic needle clamp material mechanism for grabbing layer unit.Working, industrial robot and rotary workbench multi-axis linkage, automatically grab, transfer, lay and rotary needle punching forming of layer unit are sequentially completed, realize the full-process automation of rotary preform from feeding to needle punching.The present application also includes the preparation method for using the above-mentioned robot to prepare rotary preform needle punching.The present application can be adapted to different sizes, curvature of rotary body workpiece, effectively improve the layer precision, needle punching uniformity, product consistency and forming efficiency, quality, reduce manual labor intensity and production cost.

Description

Technical Field

[0001] This invention belongs to the interdisciplinary technical field of textile composite material manufacturing, three-dimensional needle punching equipment and industrial robot application, and specifically relates to a rotary preform needle punching robot with integrated automatic feeding and its preparation method. Background Technology

[0002] Rotary structural composite preforms are widely used in high-end equipment fields such as rocket engine nozzles, aircraft brake discs, and missile nose cones in aerospace and defense industries. Their molding quality directly determines the mechanical properties and service life of downstream components. Needle punching is a key process in the preparation of rotary preforms. Its function is to interweave and fix the fiber preforms to form a three-dimensional preform structure with a certain thickness and structural strength.

[0003] Currently, the needle punching and forming of rotary preforms mostly adopts manual or semi-automated operation methods, which mainly have the following problems: the feeding process relies on manual labor to complete the conveying, laying, cutting and positioning, which is labor-intensive and prone to operational errors, resulting in insufficient fiber laying accuracy; the equipment has poor versatility, making it difficult to adapt to rotary workpieces of different sizes and curvatures, and it is difficult to guarantee the needle punching accuracy of the normal direction of the rotary surface, which is prone to problems such as uneven needle punching depth and fiber breakage; the connection between each process is cumbersome, requiring manual intervention and switching, resulting in low efficiency and poor molding consistency.

[0004] Related patents and literature also reflect the aforementioned technical problems. Patent CN105755680B discloses a robotic needle-punching device, which, although achieving needle-punching of complex spatial curved surface preforms, lacks an integrated automatic feeding function, still requiring manual intervention in the feeding and laying stages, failing to solve the problem of cumbersome process connections. Patent CN109385753A discloses a rotary preform needle-punching equipment modified from a traditional flatbed needle-punching machine. This machine adopts a fixed lifting needle beam structure, limiting the range of motion of the needle-punching mechanism. It can only rely on the rotation and swing of the core mold itself in conjunction with the up-and-down lifting of the needle beam to complete the needle-punching, resulting in poor flexibility in the working space and trajectory, and limited applicability to a single product. The article "Research Progress of Three-Dimensional Needling Technology" published in the *Journal of Textile Research* points out that rotary preform needle-punching forming equipment still faces the problem of insufficient automation, and integrated automated equipment is urgently needed.

[0005] In summary, existing rotary preform needle punching molding technology has shortcomings such as low automation, reliance on manual feeding, poor equipment versatility, difficulty in guaranteeing needle punching accuracy and molding consistency, and cumbersome process connections, making it difficult to meet the needs of large-scale and high-precision preparation of high-end preforms. Summary of the Invention

[0006] This invention provides an integrated automatic feeding rotary preform needle punching robot and its preparation method to solve the technical problems existing in the prior art. The equipment can realize the automated forming of rotary composite material preforms from automatic gripping and laying of layup units, rotary mandrel driving to multi-axis linkage precision needle punching process, and can adapt to rotary workpieces of different sizes and curvatures, ensuring needle punching accuracy and forming quality.

[0007] This invention includes the following technical solution: a rotary preform needle-punching robot with integrated automatic feeding, comprising an industrial robot, a robot base, an end effector, a worktable, and a T-shaped worktable, and further comprising an orthogonal reference limiting component; the industrial robot is mounted on the robot base; the worktable includes a rotary worktable and a core mold disposed on the rotary worktable, the rotary worktable being mounted on the T-shaped worktable via a rotary worktable base; the orthogonal reference limiting component is disposed between the industrial robot and the worktable at a distance of 500 mm from the robot base. At a distance of mm, a double-reference boundary is used to constrain the position and orientation of the material, which is perpendicular to each other. This provides a double-reference boundary constraint for the layup unit, and the size of the double-reference boundary is adjustable to accommodate the positioning of layup units of different specifications. The end effector is installed at the end of the industrial robot and integrates a needle punching mechanism and a pneumatic needle gripper for gripping the layup unit. Under the linkage and cooperation of the industrial robot and the rotary table, the needle punching mechanism and the pneumatic needle gripper sequentially complete the automatic gripping, transfer, layup and rotary needle punching of the layup unit.

[0008] Furthermore, the industrial robot is a six-axis industrial robot, equipped with a controller, servo driver, servo motor, reducer and encoder. The encoder transmits position signals back in real time to form closed-loop control, realizing continuous and smooth multi-axis linkage of the end effector.

[0009] Furthermore, the robot base and the rotary table base are 700mm apart, and both are frame structures with legs, which respectively raise the industrial robot and the rotary table, so that the end effector can stably reach the working area above the core mold.

[0010] Furthermore, the end effector includes a robot adapter flange, a fixed mounting beam, and a side frame; the robot adapter flange is connected to the end flange of the sixth axis of the industrial robot, and the fixed mounting beam and the side frame constitute the main frame.

[0011] Furthermore, the needle-punching mechanism includes a needle-punching cylinder, an optical axis, an extended round flange linear bearing, a sliding needle-punching connecting plate, a needle plate, a needle, and a stripping plate; the needle-punching cylinder is fixed under the robot adapter flange, the optical axis is arranged along the fixed mounting beam, the sliding needle-punching connecting plate slides with the optical axis via the extended round flange linear bearing, the needle plate is fixed to the sliding needle-punching connecting plate, the needle is arranged on the needle plate, the stripping plate is arranged on the outside of the needle plate, and the needle-punching cylinder drives the needle plate and the needle to reciprocate along the axial direction of the optical axis.

[0012] Furthermore, a solenoid valve and a solenoid valve manifold are also provided on the fixed installation crossbeam. The solenoid valve is fixed by the solenoid valve manifold and is used for the operation of the needle-piercing cylinder and the pneumatic needle clamp material-taking mechanism.

[0013] Furthermore, the pneumatic needle clamp picking mechanism includes a pneumatic needle clamp lifting cylinder, a miniature wide-width ball linear guide rail, a lifting connecting plate, a needle clamp mounting bracket, and a pneumatic needle clamp; the miniature wide-width ball linear guide rail is disposed on the side frame, the lifting connecting plate slides in cooperation with the miniature wide-width ball linear guide rail, the pneumatic needle clamp is mounted on the lifting connecting plate via the needle clamp mounting bracket, and the pneumatic needle clamp lifting cylinder drives the lifting connecting plate to rise and fall, thereby realizing the extension and retraction of the pneumatic needle clamp.

[0014] Furthermore, there are three sets of pneumatic needle clamps arranged side by side along the length of the end effector, and the needle insertion depth and needle insertion angle of the pneumatic needle clamps are adjustable.

[0015] Furthermore, the core mold is a hollow reinforced structure with a brush layer on its surface and a thermoplastic film isolation layer on the outside of the brush layer; the brush layer forms a relief space when the needle is inserted, and the thermoplastic film isolation layer is used to reduce demolding resistance.

[0016] A method for preparing a rotary preform by needle punching, using the aforementioned rotary preform needle punching robot with integrated automatic feeding, includes the following steps: S1. Ply Design: Import the prefabricated digital model, discretize the ply surface profile in the thickness direction according to the target thickness of the unit layer, establish the cutting reference plane and cut the ply surface, then flatten the cut ply plane and output the DXF file of each ply. S2, pre-punching of mesh / base fabric unit layer: carbon fiber cloth and carbon fiber mesh are laid alternately (specifically, one layer of carbon fiber cloth and one layer of carbon fiber mesh are laid in a cycle unit layer by layer, and the carbon fiber cloth is laid alternately at 0 / 90° orthogonal, and pre-punched into rolls by flat needle punching machine. S3. CNC cutting and storage: Based on the DXF file, the CNC cutting machine is controlled to cut the layered units with precise outer contours and stack them sequentially at the loading position of the orthogonal reference limiting component. S4. Needle punching mold preparation: Wrap the surface of the core mold with a thermoplastic film; S5. Robot Programming: Set the motion trajectory, gripping position, gripping depth, total thickness of preform blank, thickness increase of each pass of needle-punched fabric, needle-punching depth and needle-punching step of the industrial robot, and set the needle-punching depth and needle-punching angle of the pneumatic needle clamp. S6. Layup unit gripping, fixed-point transfer and placement: The industrial robot, equipped with the end effector, moves to the loading position, and the pneumatic needle clamp extends and inserts into the layup unit to complete gripping, transfers and places it at the preset station of the core mold. S7. First Needling: The industrial robot drives the needling mechanism to start needling at the 90° position. The rotary table cooperates with the industrial robot to needle counterclockwise in a step-by-step manner to the 180° position, so that the layup unit is attached and fixed to the surface of the core mold. S8. Rotary needle punching operation: After the rotary worktable drives the core mold to rotate to the initial reference position, it performs step-by-step needle punching in the counterclockwise direction to complete the processing of the entire layup unit. S9. Automated needle punching operation: Repeat steps S6-S8 to complete the overall needle punching and forming of the preform layer by layer.

[0017] Furthermore, in step S6, the pneumatic needle clamp is aligned with the preset position of the leading edge of the layup unit, and at the same time, the needle inside the pneumatic needle clamp is simultaneously inserted into the first layer of the layup unit to complete the gripping; after gripping, the layup unit is accurately positioned at 1 / 4 of the distance from the leading edge to the 90° position of the core mold.

[0018] Furthermore, in step S8, after the entire layup unit is processed, the needle is completely retracted, and the core mold is slightly rotated 1° along its original direction before stopping.

[0019] Compared with the prior art, the present invention has the following advantages and positive effects: This invention employs a multi-functional end effector that integrates automatic feeding and automatic needle punching mechanisms. Through the coordinated operation of a six-axis industrial robot and a rotary worktable, it can sequentially complete the automatic gripping, transfer, placement, and rotary needle punching of layup units, achieving integrated automatic operation of feeding, placement, and needle punching, significantly improving production efficiency and molding consistency. It eliminates the need for manual intervention in feeding and process switching, effectively solving the problems of manual feeding and cumbersome process connections in existing technologies, reducing labor intensity, improving production cycle time and molding consistency in batch production, while also reducing the risk of workplace injuries and facilitating standardized workshop management.

[0020] This invention utilizes orthogonal reference limiting components and mutually perpendicular double reference boundaries to constrain the position and orientation of the layup units. The dimensions of these double reference boundaries are adjustable, enabling compatibility with different specifications of layup units and ensuring consistent loading position accuracy, thus improving the positioning and placement accuracy of the layup units. During gripping, the pneumatic needle clamp adheres to the leading edge of the layup unit and simultaneously inserts into the first layer. After transfer, the layup unit is precisely positioned at a distance of 1 / 4 from the leading edge edge at the 90° station of the mandrel, further improving the placement and positioning accuracy of the layup units on the mandrel and reducing manual placement errors.

[0021] This invention employs a six-axis industrial robot in conjunction with a rotary table for multi-axis linkage. The end effector enables continuous and smooth spatial trajectory motion, adapting to rotating workpieces of different sizes and curvatures. The needle-punching mechanism is guided by the sliding cooperation between the optical axis and the extended circular flange linear bearing. The needle reciprocates stably along a set direction. Combined with the stepping rotation of the rotary table, it ensures the normal needle-punching accuracy of the rotating surface, making the needle-punching depth uniform, reducing needle deviation and fiber breakage, enhancing the normal adaptability and needle-punching quality of the rotating surface, and improving the structural strength and mechanical properties of the preform.

[0022] The robot base and rotary table base of this invention both adopt a frame structure with support legs, which raises the industrial robot and rotary table respectively, so that the end effector can stably reach the working area above the core mold. The structure layout is reasonable and the movement is smooth and reliable. The needle punching mechanism adopts the cooperation of optical shaft and extended round flange linear bearing to ensure the smoothness of needle punching reciprocating motion. The solenoid valve and manifold are integrated on the fixed installation crossbeam, and the air circuit layout is compact, which improves the consistency of action response and the reliability of operation of the needle punching cylinder and pneumatic needle clamping mechanism.

[0023] The core mold of this invention adopts a hollow and reinforced structure, with a brush layer on the surface and an outer thermoplastic film isolation layer. The brush layer can form a relief space when the needle is inserted, avoiding hard impact from the needle and reducing the risk of needle breakage; the thermoplastic film isolation layer can reduce demolding resistance, facilitate complete demolding of the preform, reduce surface damage, and improve the surface quality and dimensional accuracy of the final preform.

[0024] The pneumatic needle clamp used in this invention can achieve efficient layer separation of stacked fabrics due to its adjustable needle depth and needle angle. The three sets of pneumatic needle clamps work together to ensure uniform force on the material, making it less likely to damage thin materials and ensuring stable and smooth material supply.

[0025] This invention utilizes layup units whose contours and materials are determined through digital and refined design. The fiber morphology is fixed through pre-needling, and then CNC precision cutting yields standard layup units. Uniformly sized layup units enable precise alignment of layup interfaces, ensuring stable and controllable single-layer quality. This, in turn, regulates the preform's bulk density, improving molding quality and finished product yield. The use of a programmable, precisely planned industrial robot for needle punching trajectory allows for highly precise control of needle punching position, path, and step size, effectively enhancing the overall needle punching uniformity and molding stability of the preform. This invention achieves digital and parametric control of layup design, cutting, placement, and needle punching, meeting the demands for large-scale, high-precision fabrication of high-end rotary structure composite preforms. Attached Figure Description

[0026] Figure 1 This is a schematic diagram showing the installation positions of each device in the integrated automatic feeding rotary preform needle punching robot of the present invention. Figure 2 This is a schematic diagram of the front of the end effector and its mounting structure in this invention; Figure 3 This is a schematic diagram of the reverse side of the end effector and its mounting structure in this invention; Figure 4 This is a schematic diagram of the structure of the workbench in this invention; Figure 5 yes Figure 4 A partially enlarged structural diagram of section I of the middle workbench; Figure 6 This is a schematic diagram showing the shape that the preform blank needs to be pre-cut into in this invention; Figure 7 This is a schematic diagram illustrating the positional change of the worktable before and after rotation in this invention; In the diagram, 1. Industrial robot; 2. Robot base; 3. End effector; 4. Worktable; 5. T-shaped worktable; 6. Orthogonal reference limit assembly; 7. Robot adapter flange; 8. Needle cylinder; 9. Solenoid valve; 10. Stripping plate; 11. Needle; 12. Solenoid valve manifold; 13. Optical axis; 14. Extended round flange linear bearing; 15. Sliding needle connecting plate; 16. Needle plate; 17. Lifting connecting plate; 18. Side frame; 19. Fixed mounting beam; 20. Pneumatic needle clamp; 21. Needle clamp mounting bracket; 22. Miniature wide-width ball linear guide; 23. Pneumatic needle clamp lifting cylinder; 24. Cylinder fixing pad; 25. Rotary worktable; 26. Rotary worktable base; 27. Adapter flange; 28. Core mold. Detailed Implementation

[0027] To further disclose the invention's content, features, and effects, the following examples are provided in conjunction with the accompanying drawings for detailed explanation. In the following description of the embodiments, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are used solely for the convenience of describing this patent and for simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this patent.

[0028] In the following description of the embodiments, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "setting" should be interpreted broadly. For example, they can refer to a fixed connection or setting, a detachable connection or setting, or an integral connection or setting. Those skilled in the art can understand the specific meaning of the above terms in this patent according to the specific circumstances.

[0029] Example: See Appendix Figure 1-7 A rotary preform needle-punching robot with integrated automatic feeding is described in this embodiment. The industrial robot 1 is a Kawasaki RS050N robot; the needle-punching cylinder 8 is an Airtac SDAS32×40 thin cylinder; the pneumatic needle clamp lifting cylinder 23 is an Airtac ACE16×20 thin cylinder; the miniature wide-width ball linear guide 22 is a Shanglong SWHC-H9-1-L80-E10; the pneumatic needle clamp 20 is a Xirig GN2010 four-needle standard pneumatic needle clamp; and the rotary worktable 25 is a TK13500EL CNC vertical / horizontal rotary table. Rotary worktable; Solenoid valve 9 is an Airtac 4V210-08 solenoid valve; Solenoid valve manifold 12 is an Airtac 200M-2F solenoid valve manifold; Optical shaft 13 is a No. 45 surface-hardened optical shaft; Fixed mounting beam 19, sliding needle-punching connecting plate 15, lifting connecting plate 17, side frame 18 and solenoid valve manifold 12 are made of aluminum alloy; Stripping plate 10 is made of SUS304 stainless steel; Needle plate 16 is made of bakelite.

[0030] The system includes an industrial robot 1, a robot base 2, an end effector 3, a worktable 4, and a T-shaped worktable 5, as well as an orthogonal reference limiting component 6. The industrial robot 1 is mounted on the robot base 2. The worktable 4 includes a rotary worktable 25 and a core mold 28 disposed on the rotary worktable 25. The rotary worktable 25 is mounted on the T-shaped worktable 5 via a rotary worktable base 26. The orthogonal reference limiting component 6 is disposed between the industrial robot 1 and the worktable 4 at a distance of 500mm from the robot base 2 and uses mutually perpendicular double reference boundaries to constrain the position and orientation of the material. It is used to provide mutually orthogonal double reference boundary constraints for the layup units, and the size of the double reference boundaries is adjustable to accommodate the positioning of layup units of different specifications. The end effector 3 is installed at the end of the industrial robot 1 and integrates a needle punching mechanism and a pneumatic needle clamping mechanism for gripping the layup unit. Under the linkage and cooperation of the industrial robot 1 and the rotary table 25, the needle punching mechanism and the pneumatic needle clamping mechanism sequentially complete the automatic gripping, transfer, layup and rotary needle punching of the layup unit.

[0031] The industrial robot 1 is a six-axis industrial robot equipped with a controller, servo drivers, servo motors, reducers, and encoders. The industrial robot 1 relies on the controller to perform trajectory interpolation and synchronously sends commands to the servo drivers of each axis, driving the servo motors to move the six joints in a coordinated manner via the reducers. The encoder transmits position signals in real time to form a closed-loop control, enabling continuous and smooth multi-axis linkage of the end effector 3. The robot base 2 is 700mm away from the rotary table base 26, and both are frame structures with legs, raising the industrial robot 1 and the rotary table 25 respectively, allowing the end effector 3 to stably reach the working area above the core mold 28. The end effector 3 includes a robot adapter flange 7, a fixed mounting beam 19, and a side frame 18; the robot adapter flange 7 is connected to the sixth axis end flange of the industrial robot 1, and the fixed mounting beam 19 and the side frame 18 form the main frame. The fixed installation beam 18 is also equipped with a solenoid valve 9 and a solenoid valve manifold 12. The solenoid valve 9 is fixed by the solenoid valve manifold 12 and is used for the operation of the needle cylinder 8 and the pneumatic needle clamp material picking mechanism.

[0032] The needle-punching mechanism includes a needle-punching cylinder 8, an optical axis 13, an extended round flange linear bearing 14, a sliding needle-punching connecting plate 15, a needle plate 16, a needle 11, and a stripping plate 10. The needle-punching cylinder 8 is fixed under the robot adapter flange 7. The optical axis 13 is arranged along the fixed mounting beam 19. The sliding needle-punching connecting plate 15 slides with the optical axis 13 via the extended round flange linear bearing 14. The needle plate 16 is fixed to the sliding needle-punching connecting plate 15. The needle 11 is arranged on the needle plate 16. The stripping plate 10 is arranged on the outside of the needle plate 16. The needle-punching cylinder 8 drives the needle plate 16 and the needle 11 to reciprocate along the axial direction of the optical axis 13.

[0033] The pneumatic needle clamp feeding mechanism includes a pneumatic needle clamp lifting cylinder 23, a miniature wide-width ball linear guide rail 22, a lifting connecting plate 17, a needle clamp mounting bracket 21, and a pneumatic needle clamp 20. The miniature wide-width ball linear guide rail 22 is mounted on the side frame 18. The lifting connecting plate 17 slides with the miniature wide-width ball linear guide rail 22. The pneumatic needle clamp 20 is mounted on the lifting connecting plate 17 via the needle clamp mounting bracket 21. The pneumatic needle clamp lifting cylinder 23 drives the lifting connecting plate 17 to rise and fall, thereby realizing the extension and retraction of the pneumatic needle clamp 20. There are three sets of pneumatic needle clamps 20, arranged side by side along the length of the end effector 3, and the needle insertion depth and needle insertion angle of the pneumatic needle clamps 20 are adjustable.

[0034] The core mold 28 has a hollow, reinforced structure, ensuring structural strength while reducing its weight. The surface of the core mold 28 has brush holes, and it is integrally 3D printed, significantly reducing manufacturing costs. A brush layer approximately 20mm high covers the core mold 28; when the needle tip pierces, the brush bristles are pushed apart, creating a clearance space to absorb the piercing impact and prevent the needle tip from directly impacting the internal wooden core mold and breaking the needle. Compared to traditional methods using high-density sponge, the brush is less prone to damage and deformation, can be reused for a long time, and does not require frequent replacement of consumables, effectively reducing production costs. The brush layer is covered with a thermoplastic film isolation layer; the thermoplastic film is thin, soft, and freely deformable, does not affect the needle-punching process at room temperature, and reduces frictional resistance during demolding, preventing the needle-punched preform from sticking to the core mold 28, ensuring smooth demolding and avoiding deformation and damage. Utilizing the heat-shrinking property of the thermoplastic film, it can be easily separated from the needle-punched preform after processing; it is low-cost and cost-effective.

[0035] The present invention also provides a method for preparing a rotary preform by needle punching using the above-mentioned robot, specifically including the following steps: S1. Ply Design: Import the prefabricated digital model into SolidWorks. Based on the target thickness of the unit layer, use the surface equidistant and trim commands to discretize and generate the ply surface profile in the thickness direction. Establish the cutting reference plane and cut the ply surface. Finally, flatten the cut ply plane based on the flatten command and output the DXF file of each ply. S2, pre-punching of mesh / base fabric unit layer: using twill carbon fiber cloth, the carbon fiber cloth and carbon fiber mesh are laid alternately (specifically, one layer of carbon fiber cloth and one layer of carbon fiber mesh are laid as a cycle unit layer by layer, and the carbon fiber cloth is laid alternately at 0 / 90° orthogonal, and pre-punched into rolls by flat needle punching machine. S3. CNC cutting and storage: Based on the DXF file, write a CNC cutting program to control the CNC cutting machine to cut ply units with precise outer contours, and stack all ply units in a certain order at the loading position of the orthogonal reference limiting component 6. S4. Needle punching mold preparation: Wrap the surface of the core mold 28 with a thermoplastic film; S5. Robot Programming: Set parameters such as the motion trajectory, gripping position, gripping depth, total thickness of preform blank, thickness increase of each needle-punched fabric, lifting height of the needle-punching mechanism, needle-punching depth and needle-punching step amount of the industrial robot 1, and set parameters such as needle-punching depth and needle-punching angle of the pneumatic needle clamp 20. S6. Layup Unit Grabbing, Point-to-Point Transfer and Laying: The industrial robot 1, equipped with the end effector 3, moves along a preset trajectory and positions itself above the designated working position (i.e., the loading position) of the layup unit within the orthogonal reference limit assembly 6. Through the coordinated action of the solenoid valve 9 and the pneumatic needle clamp lifting cylinder 23, the pneumatic needle clamp 20 extends and tightly fits against the preset working position of the leading edge of the layup unit. Figure 6 As shown in the shaded area, the internal needles of the pneumatic needle clamp 20 simultaneously pierce the first layer of the layup unit, completing a stable grip. After gripping, the industrial robot 1, equipped with the end effector 3, adjusts to a working height slightly higher than the top of the core mold 28. At this time, the initial posture of the rotary table is as follows: Figure 7 As shown in (a), the layup unit is precisely positioned at 1 / 4 of the distance from the leading edge to the 90° position of the needle core mold. Then, the pneumatic needle clamp 20 is released and retracted, so that the leading edge of the layup unit drops to the 180° position to complete the precise positioning and laying of the unit layer, ready to carry out the first needle punching operation. S7. First Needling: The industrial robot 1 drives the end effector to move to the 90° needle-punching position along a preset trajectory. The needle-punching mechanism begins needle-punching at the 90° position. The position, range, and rotation direction of the rotary table for the first needle-punching are shown in Figure 7(a). The rotary table 25, in cooperation with the industrial robot 1, needles counterclockwise in a step-by-step manner to the 180° position, i.e., the position of the leading edge of the layup unit, so that the layup unit is attached and fixed to the surface of the core mold, completing the positioning and shaping. When completed, the posture of the rotary table 25 is as follows: Figure 7 As shown in (b); S8. Rotary needle punching operation: The rotary worktable 25 drives the core mold 28 to rotate back to the initial reference position. Figure 7 (a) After that, the rotary table 25 switches the rotation direction and performs step-by-step needle punching in the counterclockwise direction to complete the processing of the entire layup unit; after the operation is completed, the needle 11 is completely retracted, and the core mold 28 is slightly rotated 1° in the original direction and then stops. S9. Automated needle punching operation: After the needle punching process of the first layer layup unit is completed, the equipment automatically resets. The industrial robot 1 drives the end effector 3 to return to the orthogonal reference limit component 6 loading position. Repeat steps S6-S8 to complete the overall needle punching and forming of the preform layer by layer.

[0036] Although preferred embodiments of the present invention have been described above, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art, under the guidance of the present invention, can make many other modifications without departing from the spirit and scope of the claims. These modifications all fall within the scope of protection of the present invention.

Claims

1. A rotary preform needle-punching robot with integrated automatic feeding, comprising an industrial robot, a robot base, an end effector, a worktable, and a T-shaped worktable, characterized in that: It also includes an orthogonal reference limiting component; the industrial robot is mounted on the robot base; the worktable includes a rotary worktable and a core mold disposed on the rotary worktable, the rotary worktable being mounted on the T-shaped worktable via a rotary worktable base; the orthogonal reference limiting component is disposed between the industrial robot and the worktable and uses mutually perpendicular double reference boundaries to constrain the material position and orientation; the end effector is mounted on the end of the industrial robot and integrates a needle punching mechanism and a pneumatic needle clamping mechanism for gripping layup units; the needle punching mechanism and the pneumatic needle clamping mechanism, under the linkage and cooperation of the industrial robot and the rotary worktable, sequentially complete the automatic gripping, transfer, layup, and rotary needle punching forming of the layup units.

2. The rotary preform needle-punching robot with integrated automatic feeding according to claim 1, characterized in that: The end effector includes a robot adapter flange, a fixed mounting beam, and a side frame; the robot adapter flange is connected to the end flange of the sixth axis of the industrial robot, and the fixed mounting beam and the side frame constitute the main frame.

3. The rotary preform needle-punching robot with integrated automatic feeding according to claim 2, characterized in that: The needle-punching mechanism includes a needle-punching cylinder, an optical axis, an extended round flange linear bearing, a sliding needle-punching connecting plate, a needle plate, needles, and a stripping plate. The needle-punching cylinder is fixed under the robot adapter flange. The optical axis is arranged along the fixed mounting beam. The sliding needle-punching connecting plate slides with the optical axis via the extended round flange linear bearing. The needle plate is fixed to the sliding needle-punching connecting plate. The needles are arranged on the needle plate. The stripping plate is arranged outside the needle plate. The needle-punching cylinder drives the needle plate and needles to reciprocate along the axial direction of the optical axis.

4. The rotary preform needle-punching robot with integrated automatic feeding according to claim 3, characterized in that: The fixed installation beam is also equipped with a solenoid valve and a solenoid valve manifold. The solenoid valve is fixed by the solenoid valve manifold and is used for the operation of the needle-punching cylinder and the pneumatic needle clamping mechanism.

5. The rotary preform needle-punching robot with integrated automatic feeding according to claim 2, characterized in that: The pneumatic needle clamp feeding mechanism includes a pneumatic needle clamp lifting cylinder, a miniature wide-width ball linear guide, a lifting connecting plate, a needle clamp mounting bracket, and a pneumatic needle clamp. The miniature wide-width ball linear guide is mounted on the side frame. The lifting connecting plate slides in conjunction with the miniature wide-width ball linear guide. The pneumatic needle clamp is mounted on the lifting connecting plate via the needle clamp mounting bracket. The pneumatic needle clamp lifting cylinder drives the lifting connecting plate to rise and fall, thereby realizing the extension and retraction of the pneumatic needle clamp.

6. A rotary preform needle-punching robot with integrated automatic feeding according to any one of claims 5, characterized in that: The pneumatic needle clamp consists of three sets, arranged side by side along the length of the end effector, and the needle insertion depth and angle of the pneumatic needle clamp are adjustable.

7. The rotary preform needle-punching robot with integrated automatic feeding according to claim 1, characterized in that: The core mold is a hollow reinforced structure with a brush layer on its surface, and the brush layer is covered with a thermoplastic film isolation layer.

8. A method for preparing a rotary preform by needle punching, using a rotary preform needle punching robot with integrated automatic feeding as described in any one of claims 1-7, characterized in that, Includes the following steps: S1. Ply Design: Import the prefabricated digital model, discretize the ply surface profile in the thickness direction according to the target thickness of the unit layer, establish the cutting reference plane and cut the ply surface, then flatten the cut ply plane and output the DXF file of each ply. S2, pre-punching of mesh / base fabric unit layer: carbon fiber cloth and carbon fiber mesh are laid alternately, and the carbon fiber cloth is laid alternately at 0 / 90° orthogonal. It is pre-punched into rolls by a flat needle punching machine. S3. CNC cutting and storage: Based on the DXF file, the CNC cutting machine is controlled to cut the layered units with precise outer contours and stack them sequentially at the loading position of the orthogonal reference limiting component. S4. Needle punching mold preparation: Wrap the surface of the core mold with a thermoplastic film; S5. Robot Programming: Set the motion trajectory, gripping position, gripping depth, total thickness of preform blank, thickness increase of each pass of needle-punched fabric, needle-punching depth and needle-punching step of the industrial robot, and set the needle-punching depth and needle-punching angle of the pneumatic needle clamp. S6. Layup unit gripping, fixed-point transfer and placement: The industrial robot, equipped with the end effector, moves to the loading position, and the pneumatic needle clamp extends and inserts into the layup unit to complete gripping, transfers and places it at the preset station of the core mold. S7. First Needling: The industrial robot drives the needling mechanism to start needling at the 90° position. The rotary table cooperates with the industrial robot to needle counterclockwise in a step-by-step manner to the 180° position, so that the layup unit is attached and fixed to the surface of the core mold. S8. Rotary needle punching operation: After the rotary worktable drives the core mold to rotate to the initial reference position, it performs step-by-step needle punching in the counterclockwise direction to complete the processing of the entire layup unit. S9. Automated needle punching operation: Repeat steps S6-S8 to complete the overall needle punching and forming of the preform layer by layer.

9. The method for preparing a rotary preform by needle punching according to claim 8, characterized in that: In step S6, the pneumatic needle clamp is aligned with the preset position of the leading edge of the layup unit, and at the same time, the needle inside the pneumatic needle clamp is inserted into the first layer of the layup unit to complete the gripping; after gripping, the layup unit is accurately positioned at 1 / 4 of the distance from the leading edge to the 90° position of the core mold.

10. The method for preparing a rotary preform by needle punching according to claim 8, characterized in that: In step S8, after the entire layer unit is processed, the needle is completely retracted, and the core mold is slightly rotated 1° along its original direction and then stopped.

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