A predrilled hole type automated z-pin insertion head

Abstract

The application discloses a pre-bore type automatic Z-pin implantation head, belongs to the technical field of composite material Z-pin longitudinal reinforcement, and is connected with a six-axis mechanical arm and comprises an implantation head shell, a conveying device, a hole making device, a limiting device and a cutting device. The conveying device controls the movement and locking of continuous Z-pins and adjusts the relative position of the continuous Z-pins in the implantation head. The hole making device makes pre-bore holes for the Z-pins on a composite material structure, guarantees the hole making path and protects the continuous Z-pins. The limiting device keeps the composite material structure near the implantation hole from being raised during the pulling-out process of the hollow thin-walled steel needle, and avoids the delamination defect of the composite material structure. The cutting device cuts the continuous Z-pins that have been in the pre-bore holes, and completes the implantation of the Z-pins. The application realizes the uninterrupted, controllable and automatic implantation of the Z-pins in the composite material structure.

Description

Technical Field

[0001] This invention belongs to the field of composite material Z-pin longitudinal reinforcement technology, specifically relating to a pre-drilled hole type automated Z-pin implantation head. Background Technology

[0002] The process of preparing composite materials using prepreg layer-by-layer lamination offers advantages such as simple operation, good process consistency, and strong structural design flexibility, making laminated composites the mainstream composite material structure currently. However, the interlaminar properties of laminated composites depend almost entirely on the properties of the matrix itself, making them highly susceptible to delamination damage under external impact, thus affecting the residual mechanical properties of the composite structure. Z-pin reinforcement, an interlaminar strengthening technique that involves longitudinally implanting short, thin rods (on the order of 0.1 mm in diameter) into the laminated composite structure, has attracted widespread attention due to its low cost, ease of operation, and significant toughening effect.

[0003] Currently, the most common key equipment for Z-pin implantation includes ultrasonic implantation guns and solid steel needles. Both can be used handheld or mounted on mechanisms such as robotic arms to assist in Z-pin implantation. The former's main principle is to use a metal hammer to vibrate at a certain frequency (20~30 kHz) and amplitude (20~30 μm) to continuously hammer the rear end of the pre-cut Z-pin, thereby "knocking" the Z-pin into the workpiece. The latter's main principle is to use a solid steel needle to make a pre-drilled hole at the target implantation location, and then insert the pre-cut Z-pin into it. However, both of the above devices have their own limitations: ultrasonic implantation guns are prone to damaging the Z-pin itself, and the implantation path and the integrity of the Z-pin implantation end cannot be guaranteed during the implantation process; solid steel needles, although they solve the above drawbacks to some extent, are usually 1.5 times or more the diameter of the Z-pin, which will create a more obvious resin-rich area. Even if a solid steel needle with the same diameter as the Z-pin is used, due to the shrinkage effect of the pre-made hole, the Z-pin will be severely squeezed during the insertion process, which is very easy to cause secondary damage to the fibers of the pre-made hole wall, and will also cause damage to the Z-pin. These conditions will seriously affect the in-plane properties of the composite material structure. Summary of the Invention

[0004] To address the aforementioned shortcomings in the existing technology, this invention provides a pre-drilled hole-type automated Z-pin implantation head, which solves the problem that traditional Z-pin implantation equipment easily leads to excessive degradation of the in-plane performance of composite material structures.

[0005] To achieve the above-mentioned objectives, the technical solution adopted by the present invention is as follows: a pre-drilled hole type automated Z-pin implant head, comprising: an implant head shell, a conveying device, a hole-making device, a limiting device, and a cutting device;

[0006] The conveying device is used to control the movement and locking of the continuous Z-pins and to precisely adjust the relative position of the continuous Z-pins in the implant head;

[0007] The hole-making device is used to prepare pre-made holes for residing Z-pins on composite material structures, ensuring the hole-making path and protecting continuous Z-pins;

[0008] The limiting device is used to prevent the composite material structure near the implantation hole from bulging during the removal of the hollow thin-walled steel needle, so as to avoid delamination defects in the composite material structure.

[0009] The cutting device is used to cut the continuous Z-pins that have been deposited in the pre-drilled holes to complete the implantation of the Z-pins.

[0010] The beneficial effects of this invention are as follows: This invention discloses a pre-drilled hole type automated Z-pin implantation head. By mounting the Z-pin implantation head on a six-axis robotic arm, it is possible to perform Z-pin reinforcement operations on curved surface materials. At the same time, the implantation spacing can be dynamically adjusted during the Z-pin implantation process. By placing continuous Z-pins inside hollow thin-walled steel needles, the Z-pin reinforcement operation can be completed in one insertion, and the negative impact of Z-pin reinforcement on the in-plane properties of composite material structures can be reduced. Through the pressure plate, the problem of delamination defects in composite material structures caused during the removal of hollow thin-walled steel needles can be solved.

[0011] Furthermore: the implant head is connected to an external six-axis robotic arm via a thick connecting rod, which is used to control the spatial position and attitude of the Z-pin implant head through the movement and rotation of the six-axis robotic arm, so as to realize Z-pin implantation at any position normal of the composite material structure;

[0012] The implant head housing includes a top plate at the top of the implant head, an upper shell on the side of the implant head, and a lower shell at the bottom of the implant head.

[0013] The beneficial effects of the above-mentioned further solution are as follows: by connecting and controlling the Z-pin implant head through a six-axis robotic arm, the position and orientation of the Z-pin implant head can be controlled, thereby realizing Z-pin reinforcement operations on various curved composite material structures.

[0014] Furthermore: the conveying device includes a guide frame, a guide tube, a roller assembly, a roller support, a first servo motor, and a motor support;

[0015] The guide frame is mounted on the thick connecting rod; the catheter passes through the center of the entire implant head, with one end of the catheter mounted on the top plate and the other end mounted on the conversion stud; the roller assembly includes a main roller and a slave roller, the main roller and the slave roller are of the same specification and are both mounted on the roller bracket, the main roller is driven by a first servo motor; the first servo motor is mounted on a motor bracket; both the roller bracket and the motor bracket are mounted on the top plate.

[0016] The beneficial effect of the above-mentioned further solution is that the continuous Z-pin can be controlled to move up and down in the implant head through the conveying device, which facilitates precise Z-pin implantation in composite material structures.

[0017] Furthermore: the hole-making device includes a conversion stud and a hollow thin-walled steel needle;

[0018] The conversion stud is installed in the center of the lower shell. The upper end of the conversion stud is connected to the guide tube, and the lower end is connected to the hollow thin-walled steel needle. The hollow thin-walled steel needle is installed on the conversion stud.

[0019] The beneficial effects of the above-mentioned further solution are: by using a hole-making device, holes can be made in the composite material structure to ensure that the Z-pin passes through the composite material according to the planned penetration path, and to prevent the Z-pin from bending and splitting during the implantation process.

[0020] Furthermore: the limiting device includes a lifting module, a second servo motor, an inner plate, a thin connecting rod, and a pressure plate;

[0021] The lifting module is mounted on the top plate and driven by the second servo motor; the second servo motor is mounted on the top plate; the inner plate is mounted on the lifting module; the thin connecting rod is a rigid connection, with one end mounted on the inner plate and the other end passing through the lower shell and mounted on the pressure plate; the pressure plate has a through hole in the center and guide grooves on both sides.

[0022] The beneficial effect of the above-mentioned further solution is that, through the limiting device, it can be ensured that no bulging occurs at the Z-pin implantation site of the composite material structure, thus preventing delamination defects in the composite material structure.

[0023] Furthermore: the cutting device includes a drive wheel assembly, a third servo motor, a transmission belt, a drive rod, a cam, a cutting blade, and a spring;

[0024] The drive wheel assembly consists of one main drive wheel and two driven wheels. The main drive wheel is mounted on the shaft of the third servo motor, and the two driven wheels are of the same specification and are both mounted on the inner plate. The third servo motor is mounted on the inner plate. The transmission belt connects the main drive wheel and the driven wheels. The drive rod is a rigid connection, with one end mounted on the driven wheel and the other end passing through the lower shell and mounted on the cam. The cam is mounted on the pressure plate. The cutter has a boss below it, which is placed in the guide groove of the pressure plate. The cutter has a mounting groove in the middle and is limited by screws. The spring is installed in the mounting groove of the cutter, with one end pressing against the screw and the other end pressing against the cutter.

[0025] The beneficial effect of the above-mentioned further solution is that, through the cutting device, the continuous Z-pin residing in the composite material structure can be cut, thereby completing the implantation of Z-pin in the composite material structure. Attached Figure Description

[0026] Figure 1 A complete three-dimensional structural diagram of a pre-fabricated hole-type automated Z-pin implant head;

[0027] Figure 2 A three-dimensional structural diagram of a pre-fabricated, automated Z-pin implant head with a hidden portion of the outer shell;

[0028] Figure 3 This is a structural diagram of the pressure plate part of a pre-drilled hole type automated Z-pin implantation head;

[0029] Figure 4 This is a structural diagram of a pre-drilled hole type automated Z-pin implant head hole-making device;

[0030] Figure 5 This is a structural diagram of the drive wheel assembly of a pre-drilled hole type automated Z-pin implant head;

[0031] The components are: 1. Guide frame, 2. Guide tube, 3. Roller assembly, 4. Roller bracket, 5. First servo motor, 6. Motor bracket, 7. Thick connecting rod, 8. Top plate, 9. Conversion stud, 10. Hollow thin-walled steel needle, 11. Lower shell, 12. Lifting module, 13. Second servo motor, 14. Inner plate, 15. Thin connecting rod, 16. Pressure plate, 17. Drive wheel assembly, 18. Third servo motor, 19. Transmission belt, 20. Drive rod, 21. Cam, 22. Cutting knife, 23. Spring, 24. Z-pin, 25. Upper shell. Detailed Implementation

[0032] The specific embodiments of the present invention are described below to enable those skilled in the art to understand the present invention. However, it should be understood that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the present invention as defined and determined by the appended claims. All inventions utilizing the concept of the present invention are protected.

[0033] Z-pin reinforcement is a technique used to enhance the interlaminar properties of composite materials. It mainly involves inserting tiny metal or non-metal rods (called Z-pins) into the uncured composite material to improve its interlaminar fracture toughness and shear strength. The Z-pins can be made of metal (such as stainless steel, aluminum alloy, titanium alloy, etc.) or non-metal (such as carbon fiber, glass fiber, Kevlar, etc.), and their diameter is usually between 0.2 mm and 1.0 mm, with the most commonly used diameters being 0.3 mm and 0.5 mm.

[0034] like Figure 1 The image shown is a complete three-dimensional structural diagram of a pre-fabricated hole-type automated Z-pin implant head. Figure 2 The image shown is a three-dimensional structural diagram of a pre-fabricated, automated Z-pin implant head after the outer shell of the hidden portion is concealed. Figure 3 The diagram shown is a structural diagram of the pressure plate portion of a pre-drilled hole type automated Z-pin implant head. Figure 4 The diagram shown is a structural diagram of a pre-drilled hole type automated Z-pin implant head hole-making device. Figure 5 The diagram shown is a structural diagram of the drive wheel assembly of a pre-drilled hole type automated Z-pin implant head; the following is based on... Figure 1 , Figure 2 , Figure 3 , Figure 4 as well as Figure 5 This invention describes a pre-drilled hole type automated Z-pin implant head;

[0035] This invention provides a pre-drilled hole type automated Z-pin implant head, comprising: an implant head shell, a conveying device, a hole-making device, a limiting device, and a cutting device;

[0036] The implant head shell includes a top plate 8 at the top of the implant head, an upper shell 25 on the side of the implant head, and a lower shell 11 at the bottom of the implant head. The top plate 8, the upper shell 25, and the lower shell 11 are all fixed with screws.

[0037] The implant head is connected to an external six-axis robotic arm via a thick connecting rod 7. This is used to control the spatial position and orientation of the Z-pin implant head through the movement and rotation of the six-axis robotic arm. Then, through the cooperation of the conveying device, the hole-making device, the limiting device, and the cutting device, the Z-pin 24 can be implanted into the composite material structure at any position in the normal direction.

[0038] A conveying device is used to control the movement and locking of continuous Z-pins and to precisely adjust the relative position of the continuous Z-pins in the implantation head;

[0039] The conveying device includes: a guide frame 1, a catheter 2, a roller assembly 3, a roller bracket 4, a first servo motor 5, and a motor bracket 6; wherein, the guide frame 1 is mounted on a thick connecting rod 7; the catheter 2 passes through the center of the entire implant head, one end of the catheter 2 is mounted on the top plate 8, and the other end is mounted on the conversion stud 9; the roller assembly 3 includes a main roller and a slave roller, the main roller and the slave roller are of the same specification and are both mounted on the roller bracket 4, the main roller is driven by the first servo motor 5; the first servo motor 5 is mounted on the motor bracket 6; the roller bracket 4 and the motor bracket 6 are both mounted on the top plate 8.

[0040] In one embodiment of the present invention, both the guide frame 1 and the catheter 2 are through-hole structures, and their inner diameters are both larger than the diameter of the continuous Z-pin 24. They are located above and below the roller assembly 3, respectively, to ensure that the continuous Z-pin 24 can reach the contact position through the roller assembly 3. The contact force between the main roller and the slave roller is adjustable, and the friction force can be changed by changing the contact force between the two to precisely control the displacement of the Z-pin 24 in the implant head.

[0041] A hole-making device is used to prepare pre-made holes for residing Z-pins on composite material structures, ensuring the hole-making path and protecting continuous Z-pins;

[0042] The hole-making device includes: a conversion stud 9 and a hollow thin-walled steel needle 10; wherein, the conversion stud 9 is installed in the center of the lower shell 11, the upper end of the conversion stud 9 is connected to the guide tube 2, and the lower end is connected to the hollow thin-walled steel needle 10; the hollow thin-walled steel needle 10 is installed on the conversion stud 9.

[0043] In one embodiment of the present invention, the conversion stud 9 has a through-hole structure and is detachable and replaceable. The outer side of the upper end of the conversion stud 9 is connected to the lower shell 11 by a thread, the inner side of the upper end of the conversion stud 9 is connected to the guide tube 2 by a thread, and the inner side of the lower end of the conversion stud 9 is connected to the hollow thin-walled steel needle 10 by a thread. The hollow thin-walled steel needle 10 has a through-hole structure and is detachable and replaceable. The inner diameter of the hollow thin-walled steel needle 10 is the same as the diameter of the continuous Z-pin 24, and the wall thickness is ≤0.15 mm, which can protect the continuous Z-pin 24 from passing through the composite material structure.

[0044] A limiting device is used to prevent the composite material structure near the implantation hole from bulging during the removal of the hollow thin-walled steel needle, so as to avoid delamination defects in the composite material structure.

[0045] The limiting device includes: a lifting module 12, a second servo motor 13, an inner plate 14, a thin connecting rod 15, and a pressure plate 16; wherein, the lifting module 12 is mounted on the top plate 8 and driven by the second servo motor 13; the second servo motor 13 is mounted on the top plate 8; the inner plate 14 is mounted on the lifting module 12; the thin connecting rod 15 is a rigid connection, one end is mounted on the inner plate 14, and the other end passes through the lower shell 11 and is mounted on the pressure plate 16; the pressure plate 16 has a through hole in the center and a guide groove on each side.

[0046] In one embodiment of the present invention, the lifting module 12 moves up and down under the drive of the second servo motor 13. At the same time, the inner plate 14 connected to the lifting module 12 and the pressure plate 16 connected to the inner plate 14 through the thin connecting rod 15 also move up and down synchronously. The through hole in the center of the pressure plate 16 is used for the hollow thin-walled steel needle 10 and the continuous Z-pin 24 to pass through. The slide rails on both sides are used to constrain the movement path of the cutting blade 22. The pressure plate 16 itself can move in reverse during the process of the hollow thin-walled steel needle 10 being pulled out, so as to keep the composite material structure near the implantation hole from bulging, thereby avoiding delamination defects in the composite material structure.

[0047] A cutting device is used to cut the continuous Z-pins that have been deposited in the pre-drilled holes to complete the implantation of the Z-pins;

[0048] The cutting device includes: a drive wheel assembly 17, a third servo motor 18, a transmission belt 19, a drive rod 20, a cam 21, a cutting blade 22, and a spring 23. The drive wheel assembly 17 consists of one main drive wheel and two driven wheels. The main drive wheel is mounted on the shaft of the third servo motor 18, and the two driven wheels are identical in size and mounted on the inner plate 14. The third servo motor 18 is mounted on the inner plate 14. The transmission belt 19 connects the main drive wheel and the driven wheels. The drive rod 20 is a rigid connection; one end is mounted on the driven wheel, and the other end passes through the lower shell 11 and is mounted on the cam 21. The cam 21 is mounted on the pressure plate 16. The cutting blade 22 has a boss at its lower end, which is placed in the guide groove of the pressure plate 16. The cutting blade 22 has a mounting groove in the middle, which is limited by screws. The spring 23 is installed in the mounting groove of the cutting blade 22, with one end pressing against the screw and the other end pressing against the cutting blade 22.

[0049] In one embodiment of the present invention, the cam 21 can rotate under the drive of the drive rod 17, thereby pushing the cutter 22 to cut the continuous Z-pin 24, and completing the reciprocating motion under the action of the spring 23.

[0050] After completing the assembly of the pre-drilled hole type automated Z-pin implant head of the present invention, the entire automated implantation process is described using Z-pin reinforcement of a composite material plate structure as an example: The second servo motor 13 rotates according to the program, adjusting the bottom surface of the pressure plate 16 to be flush with the top of the hollow thin-walled steel needle 10; the first servo motor 5 rotates according to the program, adjusting the top of the continuous Z-pin 24 to be flush with the top of the hollow thin-walled steel needle 10; the robotic arm adjusts the implant head according to the pre-set working path, so that the hollow thin-walled steel needle 10 is collinear with the normal at the first implantation point, and descends along this direction until the pressure plate 16 contacts the first implantation point, thus completing the pre-implantation positioning work; the implant head descends as a whole under the drive of the robotic arm, at which time the second servo motor 13 rotates to drive the pressure plate 16 to move, so that the pressure plate 16 maintains a constant relative position with the composite material plate structure, thus, the hollow thin-walled steel needle 10 and the continuous Z-pin The Z-pin 24 can be inserted into the composite material flat plate structure simultaneously. After reaching the predetermined depth, the robotic arm drives the implantation head to rise as a whole. At this time, the first servo motor 5 and the second servo motor 13 rotate, and drive the continuous Z-pin 24 and the pressure plate 16 to move respectively, so that the continuous Z-pin 24 and the pressure plate 16 maintain the relative position of the composite material flat plate structure. After the hollow thin-walled steel needle 10 exits the composite material flat plate structure, the third servo motor 18 rotates, driving the cutter 22 to complete the cutting of the continuous Z-pin 24, completing the automated Z-pin implantation at one position of the composite material structure. By repeating the above process according to the planned path, the automated Z-pin implantation at all positions of the composite material structure can be completed.

[0051] The beneficial effects of this invention are as follows: This invention improves the Z-pin implantation efficiency by designing a pre-drilled, automated Z-pin implantation head. By mounting the implantation head on a six-axis robotic arm, it enables Z-pin reinforcement of various curved surface structures. Furthermore, the Z-pin implantation spacing can be dynamically adjusted during equipment operation. By placing continuous Z-pins inside hollow thin-walled steel needles, Z-pin reinforcement can be completed with a single insertion, thus reducing the negative impact of Z-pin reinforcement on the in-plane properties of composite material structures to a certain extent. Finally, by adding a pressure plate, the problem of potential delamination defects in composite material structures during the removal of hollow thin-walled steel needles is solved.

Claims

1. A pre-drilled hole type automated Z-pin implantation head, characterized in that, include: Implant head shell, conveying device, hole-making device, limiting device, and cutting device; The conveying device is used to control the movement and locking of the continuous Z-pins and to precisely adjust the relative position of the continuous Z-pins in the implant head; The hole-making device is used to prepare pre-made holes for residing Z-pins on composite material structures, ensuring the hole-making path and protecting continuous Z-pins; The limiting device is used to prevent the composite material structure near the implantation hole from bulging during the removal of the hollow thin-walled steel needle, so as to avoid delamination defects in the composite material structure. The cutting device is used to cut the continuous Z-pin that has been deposited in the pre-made hole to complete the implantation of the Z-pin; The conveying device includes a guide frame (1), a guide tube (2), a roller assembly (3), a roller bracket (4), a first servo motor (5), and a motor bracket (6). The guide frame (1) is mounted on the thick connecting rod (7); the catheter (2) passes through the center of the entire implant head, one end of the catheter (2) is mounted on the top plate (8), and the other end is mounted on the conversion stud (9); the roller assembly (3) includes a main roller and a secondary roller, the main roller and the secondary roller are of the same specification and are both mounted on the roller bracket (4), the main roller is driven by a first servo motor (5); the first servo motor (5) is mounted on a motor bracket (6); the roller bracket (4) and the motor bracket (6) are both mounted on the top plate (8); The hole-making device includes a conversion stud (9) and a hollow thin-walled steel needle (10). The conversion stud (9) is installed in the center of the lower shell (11). The upper end of the conversion stud (9) is connected to the guide tube (2), and the lower end is connected to the hollow thin-walled steel needle (10). The hollow thin-walled steel needle (10) is installed on the conversion stud (9). The limiting device includes a lifting module (12), a second servo motor (13), an inner plate (14), a thin connecting rod (15), and a pressure plate (16). The lifting module (12) is installed on the top plate (8) and driven by the second servo motor (13); the second servo motor (13) is installed on the top plate (8); the inner plate (14) is installed on the lifting module (12); the thin connecting rod (15) is a rigid connection, one end is installed on the inner plate (14), and the other end passes through the lower shell (11) and is installed on the pressure plate (16); the pressure plate (16) has a through hole in the center and guide grooves on both sides.

2. The pre-drilled hole type automated Z-pin implant head according to claim 1, characterized in that, The implant head is connected to an external six-axis robotic arm via a thick connecting rod (7), which is used to control the spatial position and attitude of the Z-pin implant head by moving and rotating the six-axis robotic arm, so as to realize the Z-pin (24) implantation of the composite material structure at any position normal. The implant head housing includes a top plate (8) at the top of the implant head, an upper shell (25) on the side of the implant head, and a lower shell (11) at the bottom of the implant head.

3. The pre-drilled hole type automated Z-pin implant head according to claim 1, characterized in that, The cutting device includes a drive wheel set (17), a third servo motor (18), a transmission belt (19), a drive rod (20), a cam (21), a cutting blade (22), and a spring (23). The drive wheel assembly (17) consists of a main drive wheel and two driven wheels. The main drive wheel is mounted on the shaft of the third servo motor (18). The two driven wheels are of the same specification and are both mounted on the inner plate (14). The third servo motor (18) is mounted on the inner plate (14). The transmission belt (19) is used to connect the main drive wheel and the driven wheels. The drive rod (20) is a rigid connection. One end is mounted on the driven wheel, and the other end passes through the lower shell (11) and is mounted on the cam (21). The cam (21) is mounted on the pressure plate (16). The cutter (22) has a boss below it, which is placed in the guide groove of the pressure plate (16). The cutter (22) has a mounting groove in the middle and is limited by screws. The spring (23) is installed in the mounting groove of the cutter (22), with one end pressing against the screw and the other end pressing against the cutter (22).

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