Pneumatic tufting sewing robot and sewing method thereof

Abstract

The invention relates to a pneumatic tufting sewing robot which comprises a six-degree-of-freedom robot, a tufting sewing end effector and a rotating table. The tail end of a mechanical arm of the six-degree-of-freedom robot is connected with the tufting sewing tail end executor and controls the tufting sewing tail end executor to sew a preform fabric arranged on the rotary worktable; the tufting sewing end effector comprises a displacement mechanism, a needling mechanism, a presser foot mechanism, a yarn feeding mechanism and an air shear mechanism. The yarn feeding mechanism comprises a bobbin, a yarn trapper and a broken yarn detection sensor, the bobbin is installed on a bobbin connecting plate, the yarn trapper is installed at the end, close to the bobbin, of a connecting support, a yarn feeding ejector rod is inserted into the middle of the connecting support, the broken yarn detection sensor is installed at the end, close to the tufting air cylinder, of the connecting support, and porcelain eyes are formed in the connecting support and the yarn feeding ejector rod; the rotating table device comprises a combined core mold, a core mold mounting seat, a rotating table and a working table; the invention further provides a suturing method using the robot. The tufting suturing depth is convenient to adjust, the orientation of the suturing needles is stably controlled, and the suturing efficiency is high.

Description

Technical Field

[0001] The present invention belongs to the technical field of tufting stitching of composite material preforms, and particularly relates to a pneumatic tufting stitching robot and a stitching method thereof. Background Art

[0002] Composite materials are widely used in various industries from sporting goods to aerospace aircraft due to their light weight, high strength and excellent structural durability. Tufting stitching can connect multiple layers of fabrics and plays a role in composite materials mainly by enhancing interlayer performance, improving mechanical properties, forming a three-dimensional reinforcement structure, optimizing material design and improving material durability. These characteristics make tufting stitching an important technical means for manufacturing high-performance composite materials.

[0003] The literature "3D reinforcement of stiffener-to-skin T-joints by Z-pinning and tufting" discloses a tufting stitching robot that uses a KSL KL150 tufting stitching end effector and can be used for single-sided stitching of curved preform fabrics. This end effector is driven by a motor, and the overall structure is relatively complex. At the same time, this system is not equipped with a seventh-axis rotary table, making it difficult to meet the tufting stitching requirements of complex rotary preform fabrics, and it does not integrate the motion compensation function during the tufting process, resulting in low stitching efficiency.

[0004] Chinese Patent 94194721.1 discloses a mechanical tufting head, which is suitable for a handheld tufting gun or automatically used for the tufting head of producing a single carpet. It is difficult to control the uniformity of stitching and cannot meet the requirements of the quality of tufted preforms.

[0005] The literature "Development and optimization of the tufting process for textile composite reinforcement" discloses a flat preform tufting stitching device based on a cylinder, which cannot meet the tufting stitching requirements of curved and irregular preforms. The cylinder stroke is fixed, it is difficult to adjust the tufting stitching depth, it does not have a broken yarn detection and yarn tension control function, and it does not have a motion compensation function, resulting in low stitching efficiency.

[0006] In summary, the existing tufting robots are not suitable for the tufting stitching and forming of complex and irregular preform fabrics. Therefore, it is necessary to improve the existing tufting equipment. Summary of the Invention

[0007] The present invention provides a pneumatic tufting and stitching robot and its stitching method to solve the technical problems existing in the known technology. The mechanical structure of the present invention is simple and easy to operate, the tufting and stitching depth is convenient to adjust, the orientation control of the stitching needle is stable, and it can realize continuous movement during the tufting and stitching process of the robot without frequent starting and stopping, greatly improving the stitching efficiency, and is applicable to the tufting and stitching forming of complex and irregular preform fabrics.

[0008] The present invention includes the following technical solutions:

[0009] A pneumatic tufting and stitching robot, comprising a six-degree-of-freedom robot, a tufting and stitching end effector, and a rotary worktable; the end of the robotic arm of the six-degree-of-freedom robot is connected to the tufting and stitching end effector and controls it to stitch a preform fabric arranged on the rotary worktable; the tufting and stitching end effector includes a displacement mechanism, a needle punching mechanism, a presser foot mechanism, a yarn feeding mechanism, and an air shear mechanism; the displacement mechanism includes a robot connection flange, a linear module, and a detection switch. The robot connection flange is fixed to the flange connecting plate and installed on the linear module. The robot connection flange can slide relatively in the axial direction of the lead screw of the linear module. The detection switches are arranged at both ends of the lead screw slide of the linear module. A connecting plate is installed in the middle of the linear module, and the needle punching mechanism is arranged at the other end of the connecting plate; the needle punching mechanism includes a tufting cylinder, a wire feeding ejector rod, a needle plate, and a stitching needle. The tufting cylinder is installed on one side of the connecting plate. The bottom of the tufting cylinder is provided with a needle plate, and the side is provided with a wire feeding ejector rod. The stitching needle is installed at the bottom of the needle plate through a stitching needle joint; the presser foot mechanism includes a presser foot cylinder and a presser foot. The presser foot cylinder is installed on the other side of the connecting plate. The bottom of the presser foot cylinder is provided with a presser foot. The bottom plate of the presser foot is located below the stitching needle. The piston rod of the presser foot cylinder pushes the presser foot to reciprocate to achieve fixation; the piston rod of the tufting cylinder reciprocates to drive the wire feeding ejector rod to feed yarn and drive the needle plate to reciprocate to perform needle punching; one end face of the connecting plate is installed with a cylinder connecting plate, and the other end face is installed with a yarn tube connecting plate and a connecting bracket. The three are located on both sides of the tufting cylinder and the presser foot cylinder; the yarn feeding mechanism includes a yarn tube, a wire clamp, and a broken wire detection sensor. The yarn tube is installed on the yarn tube connecting plate. The connecting bracket is close to one end of the yarn tube and installs a wire clamp, inserts into the wire feeding ejector rod in the middle, and installs a broken wire detection sensor at one end close to the tufting cylinder. Porcelain eyes are provided on the connecting bracket, the wire feeding ejector rod, and the needle plate; the air shear mechanism includes a pneumatic scissors and a direct drive cylinder. The direct drive cylinder is fixedly installed on the cylinder connecting plate, and the pneumatic scissors are installed at the working end of the direct drive cylinder; the rotary worktable includes a combined mandrel, a mandrel mounting seat, a rotating table, and a worktable; a rotating table is arranged on the worktable, a mandrel mounting seat is fixedly installed on the rotating table, the mandrel mounting seat is connected to the combined mandrel, and a combined foam bottom felt is installed on the surface of the combined mandrel.

[0010] Further, the detection switches are respectively installed at the starting point and the ending point of the lead screw slide table by screws; the connecting plate is integrally L-shaped, and a reinforcing rib is fixedly installed in the middle of the inner side of the L-shaped right angle by screws to improve the overall strength and enhance the anti-deformation ability.

[0011] Further, the robot connection flange and the flange connecting plate are connected by screws, and the flange connecting plate is connected to the top end of the linear module by screws; the bottom end of the slider on the lead screw of the linear module is fixed to the connecting plate by screws.

[0012] Further, the linear module is connected to the robot and the end effector as an auxiliary motion mechanism. When the robot drives the linear module slide table to move forward at a certain speed v, the servo motor of the linear module drives the lead screw to rotate in the reverse direction, so that the slider drives the end effector sewing mechanism to move at a reverse speed v. The speeds of the two are equal in magnitude and opposite in direction, so that the sewing mechanism of the end effector and the preform fabric remain relatively stationary, realizing motion compensation.

[0013] Further, magnetic switches are embedded and fixed by screws in the cylinder grooves at the starting point and the ending point in the tufting cylinder and the presser foot cylinder. The tufting sewing end effector uses compressed air as a power source to push the piston rod of the tufting cylinder to make a reciprocating motion, thereby driving the yarn feeding ejector rod to realize yarn feeding and driving the needle plate to reciprocate to realize needle punching; the piston rod of the presser foot cylinder pushes the presser foot to reciprocate to realize the fixing function.

[0014] Further, the yarn feeding ejector rod and the needle plate are connected to the tufting cylinder by screws, the needle holder is connected to the needle plate by threads, and the needle is inserted into the needle holder by fitting; the presser foot cylinder is connected to the presser foot by screws; the pneumatic scissors and the direct drive cylinder are connected by threads, and the direct drive cylinder is fixed to the cylinder connecting plate by screws and connected to the connecting plate by screws.

[0015] Further, the porcelain eyes are specifically divided into the first porcelain eye, the second porcelain eye, the third porcelain eye, the fourth porcelain eye, the fifth porcelain eye, the sixth porcelain eye, and the seventh porcelain eye according to their different positions; the yarn passes through the first porcelain eye, the tensioned thread clamp, the second porcelain eye, the third porcelain eye, the fourth porcelain eye, the fifth porcelain eye, the broken wire detection sensor, the sixth porcelain eye, and the seventh porcelain eye in sequence from the yarn bobbin, and finally penetrates into the needle; the wire-passing position of the connecting bracket is fixedly installed with porcelain eyes by tight fit.

[0016] Further, the third porcelain eye is fixedly installed in the wire-passing loop of the yarn feeding ejector rod by tight fit; the seventh porcelain eye is fixedly installed at the wire-passing position of the needle plate by tight fit; the bottom of the connecting bracket is an L-shaped composite structure, the first porcelain eye is installed at one end for accessing the yarn, the second porcelain eye and the fourth porcelain eye are respectively installed on the protruding working parts on both sides of the yarn feeding ejector rod, and the fifth porcelain eye and the sixth porcelain eye are respectively installed on the protruding working parts on both sides of the broken wire detection sensor.

[0017] Furthermore, the clamp is spiral-shaped as a whole, the nut on the middle screw can be rotated, and the top of the spring is fixed to the nut; by rotating the nut on the screw, the compression length of the spring can be changed, and the clamping force of the clamp can be adjusted; when the yarn breaks, the clamping force of the clamp spring can maintain the clamping state of the broken end.

[0018] Furthermore, the yarn tube is connected to the yarn tube connecting plate through threads, the wire clamp is connected to the connecting bracket through threads, and the wire break detection sensor is connected to the connecting bracket through screws.

[0019] Furthermore, the direct-drive cylinder adopts a rod non-rotating cylinder to ensure the linearity and consistency of the motion trajectory of the pneumatic scissors and effectively reduce the interference that may be caused by swinging.

[0020] Furthermore, the rotating table rotates according to a preset rotation speed and angle, so that complex and special-shaped preform fabrics can be tufted and sewn while rotating; the combined core mold is composed of a first combined core mold, a second combined core mold, a third combined core mold, and a fourth combined core mold, which are connected one by one with screws from top to bottom; the combined foam bottom felt includes a plurality of foam bottom felts, and each foam bottom felt is arranged corresponding to a module of the combined core mold.

[0021] A sewing method using the pneumatic tufting sewing robot comprises the following steps:

[0022] S1, install the combined core mold on the rotary table and check the reliability of the connection;

[0023] S2, installing the combined foam bottom felts one by one on the surface of the combined core mold; laying the preform fabric to be prepared on the surface of the combined foam bottom felt according to its thickness;

[0024] S3, the yarn is evenly wound on the bobbin, and along the yarn feeding path, the yarn passes through the porcelain eye on the connecting bracket near one end of the bobbin (i.e., the first porcelain eye), the tensioned wire clamp, the porcelain eye on the connecting bracket at the wire feeding side of the wire feeding ejector (i.e., the second porcelain eye), the porcelain eye at the wire feeding ejector wire passing position (i.e., the third porcelain eye), the porcelain eye on the connecting bracket at the wire feeding side of the wire feeding ejector (i.e., the fourth porcelain eye), the porcelain eye on the connecting bracket at the wire feeding side of the wire break detection sensor (i.e., the fifth porcelain eye), the wire break detection sensor, the porcelain eye on the connecting bracket at the wire breaking detection sensor wire outlet side (i.e., the sixth porcelain eye), the porcelain eye at the needle plate wire passing position (i.e., the seventh porcelain eye), and finally penetrates into the needle;

[0025] S4. Power on and start the device. The six-degree-of-freedom robot drives the tufting and sewing end effector to move to the pre-sewing point for sewing according to the set program. During the process, the linear module drives the robot to move continuously without frequent starts and stops, and real-time precise monitoring is carried out through the detection switch of the lead screw slide table; the presser foot cylinder and the tufting cylinder cooperate with each other. First, the presser foot cylinder outputs to make its piston rod push the presser foot downward to press the fabric tightly. Then, the tufting cylinder outputs to make its piston rod push the needle plate and the needles downward, and the needles penetrate into the preform fabric. After the piston rod reaches the end point, the cylinder changes direction, and the piston rod returns to the initial point. The needles and the presser foot are lifted in sequence to complete one needle punching cycle; during the yarn feeding process, the yarn breakage detection sensor monitors the yarn state in real time, discovers the yarn breakage problem in time and gives feedback;

[0026] S5. The six-degree-of-freedom robot drives the tufting and sewing end effector to move to the next sewing position, and the rotary table drives the combined core mold to complete the feeding at a predetermined angle, and continues to carry out needle punching and sewing;

[0027] S6. Repeat steps S4 - S5 until the sewing of the preform fabric is completed. The direct drive cylinder outputs to push the pneumatic scissors to move linearly, and the cylinder output of the pneumatic scissors cuts the yarn. After completion, the direct drive cylinder drives the pneumatic scissors back to the initial position;

[0028] S7. The six-degree-of-freedom robot drives the tufting and sewing end effector to return to the target stop position.

[0029] The advantages and positive effects of the present invention are as follows:

[0030] 1. The tufting action of the present invention adopts a pneumatic actuator, which has a simple structure and low cost; the stroke of the tufting cylinder is adjustable, which is convenient for quickly adjusting the tufting and sewing depth; both the tufting cylinder and the presser foot cylinder adopt a three-axis structure with guidance, and the movement is stable and the precision is high, which is suitable for the tufting and sewing of complex-shaped preform fabrics.

[0031] 2. The present invention integrates an active yarn feeding function. The return action of the tufting cylinder drives the yarn feeding ejector rod to move, so as to realize the active traction and quantitative yarn feeding; the structure is simple and the yarn feeding length is accurately controllable, which improves the stability of the sewing and forming process and the quality of the sewing and forming.

[0032] 3. The present invention integrates a yarn breakage detection function. The yarn breakage detection sensor monitors the yarn state in real time, discovers the yarn breakage problem in time and gives feedback to ensure the continuity and stability of the production process.

[0033] 4. The present invention integrates a tension control function, which can stabilize the yarn tension by adjusting the clamping force of the thread clamp. For preforms with different thicknesses and densities and different sewing yarns, the thread clamp can be flexibly adjusted to ensure tension adaptation and improve the uniformity of the finished product. At the same time, if the yarn breaks, the thread clamp can clamp the broken end to prevent the entire yarn from slipping out of the yarn feeding path, shortening the maintenance time and reducing material waste.

[0034] 5. The present invention uses porcelain eyes as the key yarn guiding components in the yarn feeding path, which can greatly reduce the friction coefficient between the yarn and the thread loop, avoid yarn fuzzing, breaking or abrasion. Especially for brittle materials or fast-running yarns, porcelain eyes can reduce mechanical damage and maintain the original strength and elasticity of the yarn. At the same time, porcelain eyes with a smooth surface are used to cooperate with components such as the thread clamp. The smooth guiding of the porcelain eyes helps to maintain the stability of the yarn tension and reduce the abnormal tension caused by fluctuations in the friction coefficient.

[0035] 6. The present invention integrates a motion compensation function. A linear module is used as an auxiliary motion mechanism to connect the robot and the end effector, which can realize the parallel operation of the continuous movement of the robot and the action of the sewing mechanism of the end effector during the tufting sewing process. The robot drives the sliding table of the linear module to move forward at a certain speed v, and the lead screw of the linear module rotates in the reverse direction, so that the slider drives the sewing mechanism of the end effector to move at a reverse speed v, making the sewing mechanism of the end effector and the preform fabric remain relatively stationary. At this time, the presser foot movement and the tufting sewing movement are completed, ensuring the quality of the sewn shape. The robot moves continuously without frequent start and stop, significantly improving the production efficiency and avoiding broken needles at the same time.

[0036] 7. The present invention uses a cylinder with a non-rotating piston rod as the driving element for the linear motion of the pneumatic scissors. The piston rod of the cylinder only moves axially, ensuring that the cutting action of the pneumatic scissors is more accurate and reducing the cutting deviation caused by rotation.

[0037] 8. The present invention is equipped with magnetic switches for the piston rod cylinders, which can synchronously feedback the stroke status of each cylinder, provide accurate position signals, and then adjust the reciprocating motion speed of the cylinders to meet the requirements of different toughness sewing yarns for the tufting sewing speed.

[0038] 9. The present invention is equipped with a seventh-axis rotary table, which can drive the fabric to step and rotate in real time, and can meet the tufting sewing and forming of complex-shaped preform fabrics while rotating.

[0039] 10. The present invention is equipped with a combined core mold, and each module of the core mold can be disassembled and assembled separately, which facilitates the demolding of the tufting-sewn preform of large-size components and is easy to disassemble and replace. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a schematic diagram of the overall structure of the equipment of an embodiment of the present invention;

[0041] Figure 2 It is a schematic diagram of the partial structure of the linear module in an embodiment of the present invention;

[0042] Figure 3 It is a right-view three-dimensional structure schematic diagram of an embodiment of the present invention;

[0043] Figure 4 It is a right-view structure schematic diagram of an embodiment of the present invention;

[0044] Figure 5 It is a front-view structure schematic diagram of an embodiment of the present invention;

[0045] Figure 6 It is a rear-view three-dimensional structure schematic diagram of an embodiment of the present invention;

[0046] Figure 7 It is a left-view three-dimensional structure schematic diagram of an embodiment of the present invention;

[0047] Figure 8 It is a schematic diagram of the partial structure of the yarn feeding mechanism in an embodiment of the present invention;

[0048] Figure 9 It is a schematic diagram of the structure of the rotary table device in an embodiment of the present invention;

[0049] Figure 10 It is a three-dimensional disassembly schematic diagram of the combined core mold in an embodiment of the present invention;

[0050] Figure 11 It is a cross-sectional structure schematic diagram of the combined core mold in an embodiment of the present invention;

[0051] In the figure, 1 - tufting and stitching end effector; 2 - six-degree-of-freedom robot; 3 - robot base; 4 - rotary table; 5 - robot connection flange; 6 - linear module; 7 - connecting plate; 8 - needle joint; 9 - needle plate; 10 - wire feeding ejector rod; 11 - connecting bracket; 12 - tufting cylinder; 13 - yarn tube connecting plate; 14 - thread clamp; 15 - yarn tube; 16 - presser foot; 17 - needle; 18 - pneumatic scissors; 19 - direct drive cylinder; 20 - cylinder connecting plate; 21 - cylinder magnetic switch;

[0052] 22 - Porcelain eye; 23 - Broken - wire detection sensor; 24 - Yarn; 25 - Presser - foot cylinder; 26 - Reinforcing rib; 27 - Flange connecting plate; 28 - Detection switch; 29 - Combined core mold; 30 - Rotary table; 31 - Workbench; 32 - Preform fabric; 33 - Combined foam bottom felt; 34 - First combined core mold; 35 - Second combined core mold; 36 - Third combined core mold; 37 - Fourth combined core mold; 38 - Core - mold mounting seat; 39 - First porcelain eye; 40 - Second porcelain eye; 41 - Third porcelain eye; 42 - Fourth porcelain eye; 43 - Fifth porcelain eye; 44 - Sixth porcelain eye; 45 - Seventh porcelain eye. Detailed implementation mode

[0053] To further disclose the content, features and effects of the present invention, the following examples are specifically cited and described in detail in conjunction with the drawings. In the description of the following embodiments, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. are based on the orientation or positional relationships shown in the drawings. These are only for the convenience of describing this patent and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of this patent.

[0054] In the description of the following embodiments, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", "connection", "setting" should be understood in a broad sense. For example, it can be fixedly connected and set, or detachably connected and set, or integrally connected and set. For those of ordinary skill in the art, the specific meanings of the above - mentioned terms in this patent can be understood according to specific situations.

[0055] Embodiment: Refer to the attached Figures 1-11 , a pneumatic tufting and sewing robot, comprising a six - degree - of - freedom robot 2, a tufting and sewing end - effector 1, and a rotary workbench 4; the end of the robotic arm of the six - degree - of - freedom robot 2 is connected to the tufting and sewing end - effector 1 and controls it to sew a preform fabric 32 arranged on the rotary workbench 4; the tufting and sewing end - effector 1 includes a displacement mechanism, a needle - punching mechanism, a presser - foot mechanism, a yarn - feeding mechanism, and an air - shearing mechanism;

[0056] As Figures 2-3As shown in the figure, the displacement mechanism includes a robot connection flange 5, a linear module 6, and a detection switch 28. The robot connection flange 5 is fixed to the flange connection plate 27 and installed on the linear module 6. The robot connection flange 5 can slide relative to the linear module 6 in the axial direction of the lead screw. The detection switches 28 are arranged at both ends of the lead screw slide of the linear module 6. The linear module 6 is connected to the six-degree-of-freedom robot 2 and the tufting and sewing end effector 1 as an auxiliary motion mechanism. A connection plate 7 is installed in the middle of the linear module 6, and a needling mechanism is arranged at the other end of the connection plate 7. The robot connection flange 5 and the flange connection plate 27 are connected by screws, and the flange connection plate 27 is connected to the linear module 6 by screws. The linear module 6 is fixed to the connection plate 7 by screws. The detection switches 28 are respectively installed at the starting point and the ending point of the lead screw slide by screws. The connection plate 7 is generally L-shaped, and a reinforcing rib 26 is fixedly installed in the middle of the inner side surface of the L-shaped right angle by screws to improve the overall strength and enhance the anti-deformation ability.

[0057] As Figure 4 shown in the figure, the needling mechanism includes a tufting cylinder 12, a wire feeding ejector rod 10, a needle plate 9, and a needle 17. The tufting cylinder 12 is installed on one side of the connection plate 7. A needle plate 9 is provided at the bottom of the tufting cylinder 12, and a wire feeding ejector rod 10 is provided on the side. The needle 17 is installed at the bottom of the needle plate 9 through a needle joint 8. The wire feeding ejector rod 10 and the needle plate 9 are connected to the tufting cylinder 12 by screws, the needle joint 8 is connected to the needle plate 9 by threads, and the needle 17 is inserted into the needle joint 8 through fitting.

[0058] As Figures 4-8 shown in the figure, the presser foot mechanism includes a presser foot cylinder 25 and a presser foot 16. The presser foot cylinder 25 is installed on the other side of the connection plate 7. The bottom of the presser foot cylinder 25 is connected to the presser foot 16 by screws. The bottom plate of the presser foot 16 is located below the needle 17. The piston rod of the presser foot cylinder 25 pushes the presser foot 16 to reciprocate to achieve fixation. The piston rod of the tufting cylinder 12 reciprocates to drive the wire feeding ejector rod 10 to achieve yarn feeding and drive the needle plate 9 to reciprocate to achieve needling. Magnetic switches 21 are embedded and fixed in the cylinder grooves at the starting point and the ending point in the tufting cylinder 25 and the presser foot cylinder 12. The tufting and sewing end effector 1 uses compressed air as a power source to push the piston rod of the tufting cylinder 12 to reciprocate, thereby driving the wire feeding ejector rod 10 to achieve yarn feeding and driving the needle plate 9 to reciprocate to achieve needling. The piston rod of the presser foot cylinder 25 pushes the presser foot 16 to reciprocate to achieve the fixation function.

[0059] As Figures 4-8As shown, one end face of the connecting plate 7 is equipped with a cylinder connecting plate 20, and the other end face is equipped with a bobbin connecting plate 13 and a connecting bracket 11. The three are located on both sides of the tufting cylinder 12 and the presser foot cylinder 25. The yarn feeding mechanism includes a bobbin 15, a thread clamp 14, and a thread break detection sensor 23. The bobbin 15 is installed on the bobbin connecting plate 13. The thread clamp 14 is installed at one end of the connecting bracket 11 close to the bobbin 15. The middle part inserts the wire feeding ejector rod 10. The thread break detection sensor 23 is installed at one end of the connecting bracket 11 close to the tufting cylinder 12. Porcelain eyes 22 are provided on the connecting bracket 11, the wire feeding ejector rod 10, and the needle plate 9. According to different positions, the porcelain eyes 22 are specifically divided into a first porcelain eye 39, a second porcelain eye 40, a third porcelain eye 41, a fourth porcelain eye 42, a fifth porcelain eye 43, a sixth porcelain eye 44, and a seventh porcelain eye 45. The bobbin 15 is threadedly connected to the bobbin connecting plate 13. The thread clamp 14 is threadedly connected to the connecting bracket 11. The thread break detection sensor 23 is screwed to the connecting bracket 11. The third porcelain eye 41 is fixedly installed in the wire passing loop of the wire feeding ejector rod 10 by a tight fit. The seventh porcelain eye 45 is fixedly installed at the wire passing position of the needle plate 9 by a tight fit. The bottom of the connecting bracket 11 is an L-shaped composite structure. The upper part of the connecting bracket 11 is an installation rod with a through groove for easy fixation to the end face of the connecting plate 7. The porcelain eye 22 installed at the wire passing position of the connecting bracket 11 is fixedly installed by a tight fit. The first porcelain eye 39 is installed at one end of the connecting bracket 11 where the yarn 24 is inserted (i.e., the end close to the bobbin 15). The second porcelain eye 40 and the fourth porcelain eye 42 are respectively installed on the protruding working parts on both sides of the wire feeding ejector rod 10. The fifth porcelain eye 43 and the sixth porcelain eye 44 are respectively installed on the protruding working parts on both sides of the thread break detection sensor 23. The yarn 24 passes through the first porcelain eye 39, the thread clamp 14 with tension, the second porcelain eye 40, the third porcelain eye 41, the fourth porcelain eye 42, the fifth porcelain eye 43, the thread break detection sensor 23, the sixth porcelain eye 44, the seventh porcelain eye 45 in sequence from the bobbin 15, and finally penetrates into the stabbing needle 17. The thread clamp 14 is integrally spiral. The nut on the middle screw rod can rotate. The top of the spring is fixed to the nut. By rotating the nut on the screw rod to change the compression length of the spring, the clamping force of the thread clamp 14 can be adjusted. When the yarn 24 breaks, the clamping force of the spring of the thread clamp 14 can maintain the clamping state of the broken end.

[0060] As Figures 4-8 shown, the air shear mechanism includes a pneumatic scissors 18 and a direct drive cylinder 19. The direct drive cylinder 19 is fixedly installed on the cylinder connecting plate 20. The pneumatic scissors 18 are installed at the working end of the direct drive cylinder 19. The pneumatic scissors 18 are threadedly connected to the direct drive cylinder 19. The direct drive cylinder 19 is fixed to the cylinder connecting plate 20 by screws and connected to the connecting plate 7 by screws. The direct drive cylinder 19 adopts a rod non-rotating cylinder to ensure the linearity and consistency of the movement track of the pneumatic scissors 18 and effectively reduce the interference that may be caused by swinging.

[0061] AsFigures 9-11 As shown, the rotary table 4 includes a combined core mold 29, a core mold mounting seat, a rotating table and a worktable; a rotating table is arranged on the worktable, a core mold mounting seat is fixedly installed on the rotating table, the core mold mounting seat is connected to the combined core mold, and a combined foam bottom felt 33 is installed on the surface of the combined core mold 29. The rotating table 30 rotates according to a preset rotation speed and angle, and can realize the tufting and sewing forming of the complex-shaped preform fabric 32 while rotating; the combined core mold 29 is successively connected by screws with a first combined core mold 34, a second combined core mold 35, a third combined core mold 36, and a fourth combined core mold 37; the combined foam bottom felt 33 includes a plurality of foam bottom felts, and each foam bottom felt is correspondingly arranged with a module of the combined core mold 29.

[0062] In this example, the robot uses a pneumatic end effector, with a simple mechanical structure, integrating an adjustable stroke and a guided cylinder, facilitating the adjustment of the tufting and sewing depth, and having stable control over the orientation of the sewing needle 17; it is equipped with functions of yarn tension control and broken yarn detection, effectively controlling the forming quality and giving broken yarn alarms; at the same time, it integrates a tufting motion compensation function, enabling continuous movement during the robot's tufting and sewing process without frequent starts and stops, greatly improving the sewing efficiency. In addition, it is equipped with a 7th-axis rotary table 4, which can realize the tufting and sewing forming of the complex-shaped preform fabric 32 while rotating.

[0063] A sewing method using the above pneumatic tufting and sewing robot includes the following steps:

[0064] S1. Install the combined core mold 29 (specifically, the first combined core mold 34, the second combined core mold 35, the third combined core mold 36, and the fourth combined core mold 37 are successively connected by screws from top to bottom) on the rotary table 4 and check the reliability of the connection;

[0065] S2. Install the combined foam bottom felts 33 one by one on the surface of the combined core mold 29; lay the preform fabric 32 to be prepared on the surface of the combined foam bottom felts 33 according to its thickness;

[0066] S3. Wind the yarn 24 evenly around the yarn bobbin 15, and then pass it through the porcelain eye 22 (i.e., the first porcelain eye 39) at one end of the connecting bracket 11 near the yarn bobbin 15, the wire clamp 14 with tension, the porcelain eye 22 (i.e., the second porcelain eye 40) on the wire inlet side of the wire feeding ejector rod 10 on the connecting bracket 11, the porcelain eye 22 (i.e., the third porcelain eye 41) at the wire passing position of the wire feeding ejector rod 10, the porcelain eye 22 (i.e., the fourth porcelain eye 42) on the wire outlet side of the wire feeding ejector rod 10 on the connecting bracket 11, the porcelain eye 22 (i.e., the fifth porcelain eye 43) on the wire inlet side of the broken wire detection sensor 23 on the connecting bracket 11, the broken wire detection sensor 23, the porcelain eye 22 (i.e., the sixth porcelain eye 44) on the wire outlet side of the broken wire detection sensor 23 on the connecting bracket 11, and the porcelain eye 22 (i.e., the seventh porcelain eye 45) at the wire passing position of the needle plate 9 along the yarn feeding path in sequence, and finally penetrate into the barbed needle 17;

[0067] S4. Start the equipment. The six-degree-of-freedom robot 2 drives the tufting sewing end effector 1 to move to the pre-sewing point for sewing according to the set program. During the process, the linear module 6 drives the robot to move continuously without frequent start and stop, and real-time accurate monitoring is carried out through the detection switch 28 of the lead screw slide table; the presser foot cylinder 25 and the tufting cylinder 12 cooperate with each other. First, the presser foot cylinder 25 outputs to make its piston rod push the presser foot 16 downward, and the presser foot 16 presses the fabric tightly. Then, the tufting cylinder 12 outputs to make its piston rod push the needle plate 9 and the barbed needle 17 downward, and the barbed needle 17 pierces into the preform fabric 32. After the piston rod reaches the end point, the cylinder changes direction, and the piston rod retracts to the initial point. The barbed needle 17 and the presser foot 16 are lifted in sequence to complete one needle punching cycle; during the yarn feeding process, the broken wire detection sensor 23 monitors the yarn state in real time and timely discovers the broken wire problem for feedback;

[0068] S5. The six-degree-of-freedom robot 2 drives the tufting sewing end effector 1 to move to the next sewing position, and the rotary table 4 drives the combined mandrel 29 to complete the feeding at a predetermined angle, and continue the needle punching sewing;

[0069] S6. Repeat steps S4 - S5 until the sewing of the preform fabric 32 is completed. The direct drive cylinder 19 outputs to push the pneumatic scissors 18 to move linearly, and the cylinder output of the pneumatic scissors 18 cuts the yarn 24. After completion, the direct drive cylinder 19 drives the pneumatic scissors 18 back to the initial position;

[0070] S7. The six-degree-of-freedom robot 2 drives the tufting sewing end effector 1 to retreat to the target stop position.

[0071] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the spirit of the present invention and the scope protected by the claims. All of these fall within the protection scope of the present invention.

Claims

1. A pneumatic tufting and sewing robot, characterized in that: It includes a six-degree-of-freedom robot (2), a tufting and sewing end effector (1), and a rotary worktable (4); the end of the robotic arm of the six-degree-of-freedom robot (2) is connected to the tufting and sewing end effector (1) and controls it to sew a preform fabric (32) arranged on the rotary worktable (4); the tufting and sewing end effector (1) includes a displacement mechanism, a needle punching mechanism, a presser foot mechanism, a yarn feeding mechanism, and an air shearing mechanism; The displacement mechanism includes a robot connection flange (5), a linear module (6), and a detection switch (28). The robot connection flange (5) is fixed to the flange connection plate (27) and installed on the linear module (6). The robot connection flange (5) can slide relative to the screw axis of the linear module (6). The detection switches (28) are arranged at both ends of the screw slide of the linear module (6). A connection plate (7) is installed in the middle of the linear module (6), and the other end of the connection plate (7) is provided with a needle punching mechanism; The needle punching mechanism includes a tufting cylinder (12), a wire feeding ejector rod (10), a needle plate (9), and a needle (17). The tufting cylinder (12) is installed on one side of the connection plate (7). The bottom of the tufting cylinder (12) is provided with a needle plate (9), and the side is provided with a wire feeding ejector rod (10). The needle (17) is installed at the bottom of the needle plate (9) through a needle joint (8); The presser foot mechanism includes a presser foot cylinder (25) and a presser foot (16). The presser foot cylinder (25) is installed on the other side of the connection plate (7). The bottom of the presser foot cylinder (25) is provided with a presser foot (16). The bottom plate of the presser foot (16) is located below the needle (17). The piston rod of the presser foot cylinder (25) pushes the presser foot (16) to reciprocate to achieve fixation; the piston rod of the tufting cylinder (12) reciprocates to drive the wire feeding ejector rod (10) to feed yarn and drive the needle plate (9) to reciprocate to achieve needle punching; One end face of the connection plate (7) is installed with a cylinder connection plate (20), and the other end face is installed with a yarn tube connection plate (13) and a connection bracket (11); the yarn feeding mechanism includes a yarn tube (15), a wire clamp (14), and a broken wire detection sensor (23). The yarn tube is installed on the yarn tube connection plate (13). The connection bracket (11) is installed with a wire clamp (14) at one end close to the yarn tube (15), inserts the wire feeding ejector rod (10) in the middle, and installs a broken wire detection sensor (23) at one end close to the tufting cylinder (12). Porcelain eyes (22) are provided on the connection bracket (11), the wire feeding ejector rod (10), and the needle plate (9); The air shearing mechanism includes a pneumatic scissors (18) and a direct drive cylinder (19). The direct drive cylinder (19) is fixedly installed on the cylinder connection plate (20), and the pneumatic scissors (18) are installed at the working end of the direct drive cylinder (19); The rotary worktable (4) includes a combined mandrel (29), a mandrel mounting seat (38), a rotating table (30), and a worktable (31); the rotating table (30) is arranged on the worktable (31), the mandrel mounting seat (38) is fixedly installed on the rotating table (30), the mandrel mounting seat (38) is connected to the combined mandrel (29), and a combined foam bottom felt (33) is installed on the surface of the combined mandrel (29).

2. The pneumatic tufting and sewing robot according to claim 1, wherein: The detection switch (28) is respectively installed at the starting point and the ending point of the lead screw slide table by screws; the connecting plate (7) is integrally L-shaped, and a reinforcing rib (26) is fixedly installed in the middle of the inner side surface of the L-shaped right angle by screws.

3. The pneumatic tufting and stitching robot according to claim 1, wherein: The cylinder magnetic switches (21) are embedded and fixed by screws in the cylinder grooves at the starting point and the ending point inside the tufting cylinder (12) and the presser foot cylinder (25).

4. The pneumatic tufting and sewing robot according to claim 1, wherein: The porcelain eyes (22) are specifically divided into a first porcelain eye (39), a second porcelain eye (40), a third porcelain eye (41), a fourth porcelain eye (42), a fifth porcelain eye (43), a sixth porcelain eye (44), and a seventh porcelain eye (45) according to their different positions; the porcelain eyes (22) are fixedly installed at the wire-passing position of the connecting bracket (11) by a tight fit.

5. The pneumatic tufting and sewing robot according to claim 4, characterized in that: The third porcelain eye (41) is fixedly installed in the wire-passing loop of the wire-feeding ejector rod (10) by a tight fit, and the seventh porcelain eye (45) is fixedly installed at the wire-passing position of the needle plate (9) by a tight fit; the bottom of the connecting bracket (11) is of an L-shaped composite structure, the first porcelain eye (39) is installed at one end where the yarn (24) is accessed, the second porcelain eye (40) and the fourth porcelain eye (42) are respectively installed on the protruding working parts on both sides of the wire-feeding ejector rod (10), and the fifth porcelain eye (43) and the sixth porcelain eye (44) are respectively installed on the protruding working parts on both sides of the broken wire detection sensor (23).

6. The pneumatic tufting and sewing robot according to claim 1, wherein: The wire clamp (14) is integrally spiral, the nut on the screw rod in the middle is rotatable, and the top of the spring is fixed to the nut; by rotating the nut on the screw rod, the compression length of the spring is changed to adjust the clamping force of the wire clamp (14).

7. The pneumatic tufting and stitching robot according to claim 1, characterized in that: The yarn bobbin (15) is threadedly connected to the yarn bobbin connecting plate (13), the wire clamp (14) is threadedly connected to the connecting bracket (11), and the broken wire detection sensor (23) is connected to the connecting bracket (11) by screws.

8. The pneumatic tufting and stitching robot according to claim 1, wherein: The direct drive cylinder (19) uses a cylinder with a non-rotating rod.

9. The pneumatic tufting and stitching robot according to claim 1, characterized in that: The rotating table (30) rotates according to a preset rotation speed and angle; the combined core mold (29) is successively connected by screws from top to bottom with a first combined core mold (34), a second combined core mold (35), a third combined core mold (36), and a fourth combined core mold (37); the combined foam bottom felt (33) includes several foam bottom felts, and each foam bottom felt is correspondingly arranged with a module of the combined core mold (29).

10. A suturing method, using the pneumatic tufting suturing robot as described in any one of claims 1-9, characterized in that, It includes the following steps: S1, install the combined core mold (29) on the rotary worktable (4); S2, successively install the combined foam bottom felts (33) on the surface of the combined core mold (29); lay the prefabricated fabric (32) to be prepared on the surface of the combined foam bottom felts (33) according to its thickness; S3. Wind the yarn (24) evenly around the yarn bobbin (15), and sequentially pass it through the porcelain eye (22) at one end of the connecting bracket (11) close to the yarn bobbin (15), the thread clamp (14) with tension, the porcelain eye (22) on the wire feeding side of the wire feeding ejector rod (10) on the connecting bracket (11), the porcelain eye (22) at the wire passing position of the wire feeding ejector rod (10), the porcelain eye (22) on the wire discharging side of the wire feeding ejector rod (10) on the connecting bracket (11), the porcelain eye (22) on the wire feeding side of the broken wire detection sensor (23) on the connecting bracket (11), the broken wire detection sensor (23), the porcelain eye (22) on the wire discharging side of the broken wire detection sensor (23) on the connecting bracket (11), and the porcelain eye (22) at the wire passing position of the needle plate (9), and finally penetrate it into the barbed needle (17); S4. Start the equipment. The six-degree-of-freedom robot (2) drives the tufting and sewing end effector (1) to move to the pre-sewing point according to the set program for sewing. During the process, the linear module (6) drives the robot to move continuously and is monitored in real time and accurately through the detection switch (28) of the lead screw slide. The presser foot cylinder (25) and the tufting cylinder (12) cooperate with each other. First, the presser foot cylinder (25) outputs to make its piston rod push the presser foot (16) downward, and the presser foot (16) presses the fabric tightly. Then, the tufting cylinder (12) outputs to make its piston rod push the needle plate (9) and the barbed needle (17) downward, and the barbed needle (17) penetrates into the preform fabric (32). After the piston rod reaches the end point, the cylinder changes direction, and the piston rod retracts to the initial point, and the barbed needle (17) and the presser foot (16) are lifted in sequence to complete one needle punching cycle. During the yarn feeding process, the broken wire detection sensor (23) monitors the state of the yarn (24) in real time and timely discovers the broken wire problem for feedback; S5. The six-degree-of-freedom robot (1) drives the tufting and sewing end effector (1) to move to the next sewing position, and the rotary table (4) drives the combined mandrel (29) to complete the feeding at a predetermined angle, and continue the needle punching and sewing; S6. Repeat steps S4 - S5 until the sewing of the preform fabric (32) is completed. The direct drive cylinder (19) outputs to push the pneumatic scissors (18) to move linearly, and the cylinder output of the pneumatic scissors (18) cuts the yarn (24). After completion, the direct drive cylinder (19) drives the pneumatic scissors (18) back to the initial position; S7. The six-degree-of-freedom robot (2) drives the tufting and sewing end effector (1) to retract to the target stop position.

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