Prefabricated hole type automatic Z-pin implanting head

Abstract

The invention discloses a prefabricated hole type automatic Z-pin implanting head, and belongs to the technical field of composite material Z-pin longitudinal strengthening, the implanting head is connected with a six-axis mechanical arm, and the implanting head comprises an implanting head shell, a conveying device, a hole forming device, a limiting device and a cutting device; the conveying device is used for controlling the movement and locking of the continuous Z-pin and adjusting the relative position of the continuous Z-pin in the implanting head; the hole making device is used for making prefabricated holes of Z-pins in the composite material structure, the hole making path is guaranteed, and continuous Z-pins are protected; the limiting device keeps that the composite material structure near the implanting hole does not bulge in the pulling-out process of the hollow thin-wall steel needle, so that the layering defect of the composite material structure is avoided; and the cutting device is used for cutting the continuous Z-pin residing in the prefabricated hole, and Z-pin implantation is completed. According to the invention, uninterrupted, controllable and automatic implantation of Z-pin in a composite material structure is realized.

Description

Technical Field

[0001] The invention belongs to the technical field of Z-pin longitudinal reinforcement of composite materials, and in particular relates to a prefabricated hole type automatic Z-pin implanting head. Background Art

[0002] The process of preparing composite materials by laying prepreg layer by layer has the advantages of simple operation process, good process consistency, and strong structural designability. Therefore, laminated composite materials are the current mainstream composite material structure. However, the interlayer performance of laminated composite materials almost entirely depends on the performance of the matrix itself, so it is very easy to suffer from delamination damage when subjected to external impact, which in turn affects the residual mechanical properties of the composite material structure. Z-pin reinforcement is an interlayer reinforcement technology that implants thin short rods (diameter of the order of 0.1mm) longitudinally into the laminated composite structure. It has attracted widespread attention due to its low cost, easy operation, and significant toughening effect.

[0003] At present, the more common key equipment for Z-pin implantation are ultrasonic implantation guns and solid steel needles, both of which can be handheld or installed on mechanical arms and other mechanisms to assist Z-pin implantation. The main principle of the former is to use a metal hammer head to vibrate at a certain frequency (20-30kHz) and amplitude (20-30μm), and continuously hammer the rear end of the cut Z-pin, thereby "knocking" the Z-pin into the workpiece; the main principle of the latter is to use a solid steel needle to pierce a prefabricated hole at the target implantation position, and then insert the cut Z-pin into it. However, both devices have their own limitations: the ultrasonic implantation gun can easily damage the Z-pin itself, and the implantation path of the Z-pin and the integrity of the Z-pin implantation end cannot be guaranteed during the implantation process; although the solid steel needle has solved the above disadvantages to a certain extent, its diameter is usually 1.5 times or more of the diameter of the Z-pin, which will cause 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 prefabricated hole, the Z-pin insertion process will be accompanied by severe extrusion, which can easily cause secondary damage to the fibers of the prefabricated hole wall and also cause damage to the Z-pin. These conditions will seriously affect the in-plane performance of the composite structure. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the present invention provides a prefabricated hole type automated Z-pin implantation head to solve the problem that traditional Z-pin implantation equipment easily causes excessive degradation in the in-plane performance of composite material structures.

[0005] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention is: a prefabricated hole type automatic 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 transmission device is used to control the movement and locking of the continuous Z-pins and to precisely adjust the relative positions of the continuous Z-pins in the implant head;

[0007] The hole making device is used to prepare prefabricated holes for resident Z-pins on the composite material structure, ensure the hole making path and protect the 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 of the composite material structure;

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

[0010] The beneficial effects of the present invention are as follows: the present invention discloses a prefabricated hole type automated Z-pin implantation head, which can perform Z-pin strengthening operations on curved surface structural materials by installing the Z-pin implantation head on a six-axis robotic arm, and can dynamically adjust the implantation spacing during the Z-pin implantation process, and can complete the Z-pin strengthening operation during sequential insertion by placing continuous Z-pins inside hollow thin-walled steel needles, and reduce the negative impact of Z-pin strengthening on the in-plane performance of composite material structures, and can solve the problem of composite material structure stratification defects caused during the removal of hollow thin-walled steel needles through a pressure plate.

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

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

[0013] The beneficial effect of the above further scheme is: by connecting and controlling the Z-pin implant head through a six-axis robotic arm, the position and posture of the Z-pin implant head can be controlled, thereby realizing Z-pin strengthening operations on various curved composite material structures.

[0014] Further: the conveying device includes a guide frame, a guide tube, a roller group, a roller bracket, a first servo motor and a motor bracket;

[0015] The guide frame is installed on the thick connecting rod; the guide tube passes through the center of the entire implant head, one end of the guide tube is installed on the top plate, and the other end is installed on the conversion stud; the roller group includes a main rolling wheel and a slave rolling wheel, the main rolling wheel and the slave rolling wheel have the same specifications and are both installed on the roller bracket, and the main rolling wheel is driven by a first servo motor; the first servo motor is installed on the motor bracket; the roller bracket and the motor bracket are both installed on the top plate.

[0016] The beneficial effect of the above further solution is that the up and down movement of continuous Z-pins in the implant head can be controlled by the conveying device, which facilitates accurate Z-pin implantation in the composite material structure.

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

[0018] The conversion stud is installed at the central position of the lower shell, the upper end of the conversion stud is connected with the guide tube, and the lower end is connected with the hollow thin-walled steel needle; the hollow thin-walled steel needle is installed on the conversion stud.

[0019] The beneficial effect of the above further scheme is: through the hole-making device, holes can be made in the composite material structure to ensure that the Z-pin passes through the composite structure material according to the planned penetration path, thereby preventing the Z-pin from bending and splitting during the implantation process.

[0020] Further: the limiting device comprises a lifting module, a second servo motor, an inner plate, a thin connecting rod and a pressing plate;

[0021] The lifting module is installed on the top plate and driven by the second servo motor; the second servo motor is installed on the top plate; the inner plate is installed on the lifting module; the thin connecting rod is a hard connection, one end of which is installed on the inner plate, and the other end passes through the lower shell and is installed on the pressure plate; a through hole is provided in the center of the pressure plate, and guide grooves are provided on both sides.

[0022] The beneficial effect of the above further solution is that the limiting device can ensure that no bulge occurs at the Z-pin implantation site of the composite material structure, thereby preventing the composite material structure from having delamination defects.

[0023] Further: the cutting device comprises a driving wheel set, a third servo motor, a transmission belt, a driving rod, a cam, a cutting knife and a spring;

[0024] The driving wheel group consists of a main driving wheel and two slave driving wheels, the main driving wheel is installed on the rotating shaft of the third servo motor, and the two slave driving wheels have the same specifications and are installed on the inner plate; the third servo motor is installed on the inner plate; the transmission belt is used to connect the main driving wheel and the slave driving wheel; the driving rod is a hard connection, one end of which is installed on the slave driving wheel, and the other end passes through the lower shell and is installed on the cam; the cam is installed on the pressure plate; the cutter contains a boss under it, which is placed in the guide groove of the pressure plate, and the cutter contains a mounting groove in the middle, which is limited by a screw; the spring is installed in the mounting groove of the cutter, one end of which supports the screw and the other end supports the cutter.

[0025] The beneficial effect of the above further solution is that the continuous Z-pins residing in the composite material structure can be cut by the cutting device to complete the implantation of the Z-pins in the composite material structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A complete three-dimensional structure diagram of a prefabricated hole automated Z-pin implant head;

[0027] Figure 2 A three-dimensional structural diagram of a prefabricated hole-type automated Z-pin implant head with part of the shell hidden;

[0028] Figure 3 A structural diagram of a prefabricated hole type automated Z-pin implant head pressure plate;

[0029] Figure 4 A structural diagram of a prefabricated hole-making device for an automated Z-pin implant head;

[0030] Figure 5 A structural diagram of a driving wheel assembly of a prefabricated hole type automated Z-pin implant head;

[0031] Wherein: 1. guide frame, 2. guide tube, 3. roller group, 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. driving wheel group, 18. third servo motor, 19. transmission belt, 20. driving rod, 21. cam, 22. cutter, 23. spring, 24. Z-pin, 25. upper shell. DETAILED DESCRIPTION

[0032] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

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

[0034] like Figure 1 As shown in FIG. 1 , a complete three-dimensional structure diagram of a prefabricated hole type automated Z-pin implant head is shown in FIG. Figure 2 As shown, it is a three-dimensional structure diagram of a prefabricated hole type automated Z-pin implant head with part of the shell hidden, as shown Figure 3 As shown in FIG. 1 , a structural diagram of a prefabricated hole type automated Z-pin implant head pressure plate portion is shown in FIG. Figure 4 As shown in FIG. 1 , a structural diagram of a prefabricated hole-making device for an automated Z-pin implant head is shown. Figure 5 As shown, it is a structural diagram of a prefabricated hole type automatic Z-pin implant head drive wheel assembly; Figure 1 , Figure 2 , Figure 3 , Figure 4 as well as Figure 5 A prefabricated hole type automated Z-pin implant head of the present invention is described;

[0035] The present invention provides a prefabricated 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 located at the top of the implant head, an upper shell 25 at 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 by screws.

[0037] The implant head is connected to an external six-axis robot through a thick connecting rod 7, and is used to control the spatial position and posture of the Z-pin implant head through the movement and rotation of the six-axis robot, and then realize the normal Z-pin 24 implantation at any position of the composite material structure through the cooperation of the conveying device, the hole making device, the limiting device and the cutting device;

[0038] A transmission device for controlling the movement and locking of the continuous Z-pins and accurately adjusting the relative positions of the continuous Z-pins in the implant head;

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

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

[0041] A hole making device is used to prepare prefabricated holes for the Z-pins on the composite structure, ensure the hole making path and protect the 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 central position of the lower shell 11, the upper end of the conversion stud 9 is connected with the catheter 2, and the lower end is connected with 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 is a through-hole structure and can be removed and replaced. 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 catheter 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 is a through-hole structure and can be removed and replaced. 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 ≤0.15mm, 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 extraction of the hollow thin-walled steel needle, so as to avoid delamination defects of 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 installed on the top plate 8 and is 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 hard connection, one end of which 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; a through hole is provided in the center of the pressure plate 16, and a guide groove is provided on both sides.

[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, and at the same time, the inner plate 14 connected to the lifting module 12 and the pressing plate 16 connected to the inner plate 14 through the thin connecting rod 15 also move up and down synchronously with it; the through hole in the center of the pressing plate 16 is used to pass the hollow thin-walled steel needle 10 and the continuous Z-pin 24, and the slide rails on both sides are used to constrain the movement path of the cutter 22. The pressing plate 16 itself can move in the opposite direction during the removal of the hollow thin-walled steel needle 10 to keep the composite material structure near the implantation hole from bulging, thereby avoiding the delamination defects of the composite material structure.

[0047] A cutting device, used for cutting the continuous Z-pins that have been retained in the prefabricated holes to complete the implantation of the Z-pins;

[0048] The cutting device includes: a driving wheel group 17, a third servo motor 18, a transmission belt 19, a driving rod 20, a cam 21, a cutting knife 22 and a spring 23; wherein the driving wheel group 17 is composed of a main driving wheel and two slave driving wheels, the main driving wheel is mounted on the rotating shaft of the third servo motor 18, and the two slave driving wheels have the same specifications 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 driving wheel and the slave driving wheel; the driving rod 20 is a hard connection, one end of which is mounted on the slave driving 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 pressing plate 16; the cutting knife 22 has a boss below, which is placed in the guide groove of the pressing plate 16, and the cutting knife 22 has a mounting groove in the middle, which is limited by a screw; the spring 23 is installed in the mounting groove of the cutting knife 22, one end of which supports the screw and the other end supports the cutting knife 22.

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

[0050] After completing the assembly of a prefabricated hole-type automated Z-pin implant head of the present invention, the entire automated implantation process is described by taking the Z-pin reinforcement of a composite material flat plate structure as an example: the second servo motor 13 rotates according to the program to adjust the bottom surface of the pressing plate 16 to a position flush with the top of the hollow thin-walled steel needle 10; the first servo motor 5 rotates according to the program to adjust the top of the continuous Z-pin 24 to a position flush with the top of the hollow thin-walled steel needle 10; the robotic arm adjusts the implantation head according to a 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 in this direction until the pressing plate 16 contacts the first implantation point, thereby completing the positioning work before implantation; the implantation head descends as a whole under the drive of the robotic arm, and at this time the second servo motor 13 rotates to drive the pressing plate 16 to move, so that the pressing plate 16 maintains a relative position with the composite material flat plate structure unchanged, so that the hollow thin-walled steel needle 10 and the continuous Z-pin 24 can be inserted into the composite material flat plate structure at the same time; after reaching the predetermined depth, the robotic arm drives the implant head to rise as a whole, at which time the first servo motor 5 and the second servo motor 13 both rotate, and respectively drive the continuous Z-pin 24 and the pressing plate 16 to move, so that the continuous Z-pin 24 and the pressing plate 16 maintain their relative positions with the composite material flat plate structure unchanged; 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, and repeating the above process according to the planned path can complete the automated Z-pin implantation at all positions of the composite material structure.

[0051] The beneficial effects of the present invention are as follows: the present invention improves the implantation efficiency of Z-pins by designing a prefabricated hole-type automated Z-pin implantation head, and realizes the operation of Z-pin strengthening of various curved surface structures by installing the implantation head on a six-axis robotic arm, while the implantation spacing of the Z-pins can be dynamically adjusted during the operation of the equipment; by placing continuous Z-pins inside hollow thin-walled steel needles, the Z-pin strengthening operation can be completed with only one insertion, which reduces the negative impact of Z-pin strengthening on the in-plane performance of the composite material structure to a certain extent; by adding a pressure plate, the problem of possible delamination defects of the composite material structure caused during the removal of the hollow thin-walled steel needles is solved.

Claims

1. A prefabricated hole type automated Z-pin implant head, characterized in that: include: Implant head shell, conveying device, hole making device, limiting device and cutting device; The transmission device is used to control the movement and locking of the continuous Z-pins and to precisely adjust the relative positions of the continuous Z-pins in the implant head; The hole making device is used to prepare prefabricated holes for resident Z-pins on the composite material structure, ensure the hole making path and protect the 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 of the composite material structure; The cutting device is used to cut the continuous Z-pins that have been retained in the prefabricated holes to complete the implantation of the Z-pins.

2. The prefabricated hole type automated Z-pin implantation head according to claim 1, characterized in that: The implant head is connected to an external six-axis mechanical arm via a thick connecting rod (7) and is used to control the spatial position and posture of the Z-pin implant head through the movement and rotation of the six-axis mechanical arm, thereby realizing the normal implantation of the Z-pin (24) at any position of the composite material structure; The implant head shell comprises a top plate (8) located at the top of the implant head, an upper shell (25) at the side of the implant head, and a lower shell (11) at the bottom of the implant head.

3. The prefabricated hole type automated Z-pin implantation head according to claim 1, characterized in that: The conveying device comprises a guide frame (1), a guide tube (2), a roller group (3), a roller bracket (4), a first servo motor (5) and a motor bracket (6); The guide frame (1) is mounted on a thick connecting rod (7); the guide tube (2) passes through the center of the entire implant head, one end of the guide tube (2) is mounted on a top plate (8), and the other end is mounted on a conversion stud (9); the roller group (3) includes a main rolling wheel and a slave rolling wheel, the main rolling wheel and the slave rolling wheel have the same specifications and are both mounted on a roller bracket (4), and the main rolling wheel 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).

4. The prefabricated hole type automated Z-pin implantation head according to claim 1, characterized in that: The hole-making device comprises a conversion stud (9) and a hollow thin-walled steel needle (10); The conversion stud (9) is installed at the central position 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).

5. The prefabricated hole type automated Z-pin implantation head according to claim 1, characterized in that: The limiting device comprises a lifting module (12), a second servo motor (13), an inner plate (14), a thin connecting rod (15) and a pressing plate (16); The lifting module (12) is mounted on the top plate (8) and driven by a 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 hard connection, one end of which is mounted on the inner plate (14) and the other end of which passes through the lower shell (11) and is mounted on the pressing plate (16); a through hole is provided in the center of the pressing plate (16) and guide grooves are provided on both sides.

6. The prefabricated hole type automated Z-pin implantation head according to claim 1, characterized in that: The cutting device comprises a driving wheel set (17), a third servo motor (18), a transmission belt (19), a driving rod (20), a cam (21), a cutting knife (22) and a spring (23); The driving wheel group (17) is composed of a main driving wheel and two slave driving wheels, the main driving wheel is mounted on the rotating shaft of the third servo motor (18), and the two slave driving wheels have the same specifications 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 driving wheel and the slave driving wheel; the driving rod (20) is a hard connection, one end of which is mounted on the slave driving 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 pressing plate (16); the cutter (22) has a boss below, which is placed in the guide groove of the pressing plate (16); the cutter (22) has a mounting groove in the middle, which is limited by a screw; the spring (23) is mounted in the mounting groove of the cutter (22), one end of which supports the screw and the other end supports the cutter (22).

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