A thermosetting composite material butt welding device and welding method

Abstract

The invention discloses a thermosetting composite material butt welding device and a welding method, and belongs to the technical field of laser welding. The invention discloses a thermosetting composite material butt welding device, and the entire welding process is automated. The joint of the composite material is clamped by two upper and lower pieces of metal, and the laser is guided by a laser through a laser guiding mechanism to heat the upper and lower pieces of metal, so that the metal and the composite material are connected together, thereby realizing butt welding between the thermosetting composite materials, thereby completing welding, having high welding efficiency, not relying on the skills of the staff, having a short production cycle, having a simple structure, being easy to operate, and having a wide range of applications.

Description

Technical Field

[0001] The invention belongs to the technical field of laser welding, and in particular relates to a thermosetting composite material butt welding device. Background Art

[0002] Thermosetting composite materials are widely used in vehicle manufacturing industry, electromechanical industry, chemical corrosion protection and construction engineering due to their low density, high strength, wide range of design performance, strong heat resistance, strong chemical corrosion resistance, good electrical conductivity and pollution-free performance. Due to its special non-thermofusible molecular cross-linking structure, the structural parts cannot be directly connected by hot-melt welding. At present, the traditional mechanical connection and adhesive bonding methods are still the main methods. Mechanical connection is completely dependent on manual labor, which has high requirements for the staff. The product quality is closely related to the staff's skills and has a long production cycle. The adhesive bonding method requires pre-impregnated tape. The whole process is cumbersome, long cycle and low efficiency. Summary of the invention

[0003] In order to solve the above problems, the present invention discloses a thermosetting composite material butt welding device. The entire welding process is automated. The joint of the composite material is clamped by two upper and lower pieces of metal. The laser is guided by a laser through a laser guiding mechanism to heat the upper and lower pieces of metal, so that the metal and the composite material are connected together, thereby completing the welding. The welding efficiency is high, there is no need to rely on the skills of the staff, and the production cycle is short.

[0004] In order to achieve the above object, the technical solution of the present invention is as follows:

[0005] A thermosetting composite material butt welding device, comprising a fiber laser, a laser guide mechanism, a metal plate, a support mechanism, a clamping mechanism and a pneumatic mechanism, wherein the support mechanism comprises a top seat, a base, a connecting support plate and a support frame, the clamping mechanism comprises a first welding pressure plate, a welding positioning groove, a second welding pressure plate, a telescopic seat, a bracket and a sliding guide rail, the pneumatic mechanism comprises a first pneumatic device, a second pneumatic device, a pneumatic piston and a third pneumatic device, the connecting support plates are two, after being placed vertically and parallel, the upper end is fixedly connected to the top seat, the lower end is connected to the base, and the middle part is connected through the support frame The metal plate is composed of two pieces. The bracket and the telescopic seat are respectively installed on the support frame and keep the upper surface in the same plane. The ends of the first pneumatic device, the second pneumatic device and the third pneumatic device are all equipped with the pneumatic piston. The pneumatic piston of the third pneumatic device is fixed to the lower end of the telescopic seat. The sliding guide rail is formed on the upper surface of the third pneumatic device and is adapted to be installed with the groove on the lower surface of the telescopic seat, so that the telescopic seat can slide back and forth along the sliding guide rail on the upper surface of the third pneumatic device. A second placement groove is formed above one end of the upper surface of the bracket. The telescopic seat and The upper ends of the surfaces opposite to the bracket are formed with a first placement groove. The first pneumatic device and the second pneumatic device are both two, which are respectively installed on the top seat and the base, and the pneumatic pistons at the end are opposite to each other. The first welding pressure plate is two, one is fixedly connected to the pneumatic piston at the end of the first pneumatic device, and the other is fixedly connected to the pneumatic piston at the end of the second pneumatic device. The welding positioning groove is formed on the first welding pressure plate, and the size is adapted to the metal plate. The two composite material plates to be butt-welded are respectively placed in the first placement groove and the second placement groove, and the upper ends are fixedly connected by the second welding pressure plate. The two composite material plates The material plates are coated with thermoplastic resin at the butt joint surfaces and butted together. The metal plates with microstructured surfaces are laid on the upper and lower surfaces of the composite material plates. The first pneumatic device, the second pneumatic device and the third pneumatic device are started, and the upper and lower first welding platens move relative to each other until the metal plates are placed in the welding positioning grooves and the composite material plates are limited in the vertical direction. The telescopic seat moves relative to the bracket along the sliding guide rail and the composite material is limited in the horizontal direction. Then, the laser guiding mechanism is used to guide the fiber laser to perform laser welding on the butt joints of the composite material.

[0006] As a further improvement of the present invention, the laser guiding mechanism includes a semi-mirror, three reflectors and two scanning galvanometer mirrors, the two reflectors and the two scanning galvanometer mirrors are symmetrically installed above and below the clamping mechanism, respectively, and a semi-mirror and a reflector are installed on one side of the clamping mechanism, respectively. The laser emitted by the laser is refracted into two beams of light by the semi-mirror, one beam of light passes through a reflector and irradiates the scanning galvanometer mirror above the clamping mechanism, and the other beam of light passes through two reflectors in turn and irradiates the scanning galvanometer mirror below the clamping mechanism, thereby performing laser welding on the composite material plates to be butt-welded installed on the clamping mechanism.

[0007] As a further improvement of the present invention, the laser is a fiber laser, a CO2 laser, or a semiconductor laser.

[0008] As a further improvement of the present invention, the thermoplastic resin is PA thermoplastic material, PC thermoplastic material, PPS thermoplastic material or PEEK thermoplastic material.

[0009] As a further improvement of the present invention, the semi-transparent mirror, the reflective mirror and the scanning galvanometer mirror are glass lenses.

[0010] The present invention also discloses a butt welding method using the above-mentioned thermosetting composite material butt welding device, and the butt welding method comprises the following steps:

[0011] S1, using a short pulse laser to clean the upper and lower surfaces of the thermosetting composite material to be processed, removing the resin layer on the surface of the composite material, so that the carbon fiber of the composite material is fully exposed, and then enters S2;

[0012] S2 uses a short pulse laser to perform microstructural processing on the surface of the metal plate, and then enters S3;

[0013] S3, using the clamping mechanism to clamp the two thermosetting composite materials processed in step S1 in pairs, adding thermoplastic resin at the butt joint, and then starting the pneumatic mechanism to tightly butt the butt joints together, adding thermoplastic resin to the lower surface of the metal plate processed in step S2 and then laying it on the upper surface of the joint of the thermosetting composite material, adding thermoplastic resin to the lower surface of the other metal plate processed in step S2 and then laying it on the lower surface of the joint of the thermosetting composite material, and then entering S4;

[0014] S4, start the laser guiding mechanism to guide the laser, the laser emitted by the laser is refracted into two beams of light through a semi-mirror, one beam of light passes through a reflector to illuminate the scanning galvanometer above the clamping mechanism, and then is reflected to the metal plate above the thermosetting composite material joint, and the other beam of light passes through two reflectors in turn to illuminate the scanning galvanometer below the clamping mechanism, and then is reflected to the metal plate below the thermosetting composite material joint. The continuous laser performs rotational track welding on the upper and lower metal plates at the same time in a defocused state until all the thermoplastic resins are fully melted, thereby completing the laser welding.

[0015] As a further improvement of the present invention, the laser has a wavelength of 1064nm and a pulse width of 50ms. In a defocused state, rotational trajectory welding is simultaneously performed on the metal plates laid on the upper and lower surfaces of the thermosetting composite material to be welded. The rotation amplitude r is 2.5mm, the distance d between the two amplitudes is 0.25mm, the trajectory is 12mm×12mm, the horizontal straight line W is 4mm, and the longitudinal straight line L is 12mm.

[0016] As a further improvement of the present invention, the thickness of the added thermoplastic resin layer is less than 1 mm.

[0017] The beneficial effects of the present invention are as follows:

[0018] 1. The present application designs a laser guiding mechanism, which is combined with a laser to heat the metal plate at the joint of the composite material plate. Through the principle of heat conduction, the added resin is melted and cooled to room temperature to achieve the connection between the metal plate and the composite material plate, thereby achieving a more stable connection between the composite materials.

[0019] 2. The present application designs a combination of a clamping mechanism and a pneumatic mechanism, which can realize automatic clamping and appropriate pressure on the composite material plate, and automated operation, which saves manpower and improves work efficiency.

[0020] In conclusion, the thermosetting composite material butt welding device of the present invention has a simple structure, is easy to operate, has high welding efficiency, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic diagram of the overall structure of the thermosetting composite butt welding device of the present invention;

[0022] Figure 2 Schematic diagram of the process of guiding the laser by the laser guiding mechanism of the present invention;

[0023] Figure 3 A schematic diagram of the structure of the clamping mechanism in the thermosetting composite butt welding device of the present invention;

[0024] Figure 4 It is a schematic diagram of the surface mesh microstructure processing process of the metal plate;

[0025] Figure 5 Schematic diagram of laser removal of the resin layer on the surface of a thermosetting composite material plate;

[0026] Figure 6 Schematic diagram of laser welding process for thermosetting composite panels;

[0027] Figure 7 This is the laser butt welding sample of the thermosetting composite material after welding.

[0028] List of Figure Symbols:

[0029] 1. Half mirror; 2. Reflector; 3. Scanning galvanometer; 21 Laser; 4. Metal plate; 6. Top seat; 9. Base; 7. Connecting support plate; 12. Support frame; 5. Clamping mechanism; 15. First welding plate; 19. Welding positioning groove; 16. Second welding plate; 17. Telescopic seat; 1701 First placement groove 18. Bracket. 1801 Second placement groove 20. Sliding guide rail 8. First pneumatic device; 11. Second pneumatic device; 10. Pneumatic piston; 13. Third pneumatic device; 14. Composite material plate. Implementation

[0030] The present invention will be further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0031] like Figure 1-3As shown, the thermosetting composite butt welding device disclosed in the present invention includes a fiber laser 21, a laser guiding mechanism, a metal plate 4, a supporting mechanism, a clamping mechanism 5 and a pneumatic mechanism, wherein the supporting mechanism includes a top seat 6, a base 9, a connecting support plate 7 and a supporting frame 12, the clamping mechanism 5 includes a first welding pressure plate 15, a welding positioning groove 19, a second welding pressure plate 16, a telescopic seat 17, a bracket 18 and a sliding guide rail 20, the pneumatic mechanism includes a first pneumatic device 8, a second pneumatic device 11, a pneumatic piston 10 and a third pneumatic device 13, and the connecting support plate 7 is two, which are placed vertically and parallel, with the upper end fixed to the top seat 6, the lower end to the base 9, and the middle part through the The support frame 12 is connected, the metal plate 4 is two pieces, the bracket 18 and the telescopic seat 17 are respectively installed on the support frame 12, and the upper surfaces are kept in the same plane. The ends of the first pneumatic device 8, the second pneumatic device 11 and the third pneumatic device 13 are all equipped with the pneumatic piston 10, and the pneumatic piston 10 of the third pneumatic device 13 is fixed to the lower end of the telescopic seat 17. The sliding guide rail 20 is formed on the upper surface of the third pneumatic device and is adapted to be installed with the groove on the lower surface of the telescopic seat 17, so that the telescopic seat 17 can slide back and forth along the sliding guide rail 20 on the upper surface of the third pneumatic device. A second placement groove 18 is formed above one end of the upper surface of the bracket 18 01, the telescopic seat 17 is formed with a first placement groove 1701 on the upper end of the surface opposite to the bracket 18, the first pneumatic device 8 and the second pneumatic device 11 are both two, which are respectively installed on the top seat 6 and the base 9, and the pneumatic pistons 10 at the end are opposite to each other, the first welding plate 15 is two, one is fixedly connected to the pneumatic piston 10 at the end of the first pneumatic device 8, and the other is fixedly connected to the pneumatic piston 10 at the end of the second pneumatic device 11, the welding positioning groove 19 is formed on the first welding plate 15, and the size is adapted to the metal plate 4, and the two composite material plates to be welded are respectively placed in the first placement groove 1701 and the second placement groove 1801, and the upper end is fixedly connected with the second The welding platen 16 is fixedly connected, and the two composite material plates are coated with thermoplastic resin at the butt surface and butt-jointed together. The metal plate 4 with microstructured surface is laid on the upper and lower surfaces of the composite material plate. The first pneumatic device 8, the second pneumatic device 11 and the third pneumatic device 13 are started, and the upper and lower first welding platens 15 move relative to each other until the metal plate 4 is placed in the welding positioning groove 19, and the composite material plate is limited in the vertical direction. The telescopic seat 17 moves relative to the bracket 18 along the sliding guide rail 20. After limiting the composite material in the horizontal direction, the laser guiding mechanism is used to guide the fiber laser 21 to perform laser welding on the butt joint of the composite material.

[0032] The laser guiding mechanism includes a semi-mirror 1, three reflectors 2 and two scanning galvanometer mirrors 3. The two reflectors 2 and the two scanning galvanometer mirrors 3 are symmetrically installed above and below the clamping mechanism 5, respectively. A semi-mirror 1 and a reflector 2 are installed on one side of the clamping mechanism 5, respectively. The laser emitted by the laser 21 is refracted into two beams of light through the semi-mirror 1. One beam of light passes through a reflector 2 and irradiates the scanning galvanometer mirror 3 above the clamping mechanism 5, and the other beam of light passes through two reflectors 2 in turn and irradiates the scanning galvanometer mirror 3 below the clamping mechanism 5, thereby performing laser welding on the composite material plate to be butt-welded installed on the clamping mechanism 5.

[0033] The laser 21 is a fiber laser, a CO2 laser or a semiconductor laser.

[0034] The thermoplastic resin is PA thermoplastic material, PC thermoplastic material, PPS thermoplastic material or PEEK thermoplastic material.

[0035] The semi-transparent mirror 1, the reflective mirror 2 and the scanning galvanometer mirror 3 are glass lenses.

[0036] Welding process:

[0037] Step 1: If Figure 4 As shown, using a wavelength of 532nm, a pulse width of 50ns laser, a mesh microstructure is prepared on the surface of the metal plate 4 with a width W1 of 25mm and a length L1 of 25mm, forming a microstructure with a depth and width of 0.1 mm, and the interval d1 of the microstructure is 0.1 mm;

[0038] Step 2: If Figure 5 As shown, using a laser with a wavelength of 532nm and a pulse width of 50ns, laser cleaning is performed on the surface of the thermosetting composite material plate 14 with a width W2 of 25mm and a length L2 of 12.5mm. Each cleaning area is 0.05mm wide and the interval d2 is 0.05mm. The resin layer on the surface of the composite material plate 14 is removed to fully expose the carbon fiber of the composite material. An ultrasonic cleaning machine is used to clean the surface microstructure of the metal plate 4 and the surface of the thermosetting composite material plate 14 after treatment;

[0039] Step 3: If Figure 6 As shown, first make two thermosetting composite plates 14 butt together, and then the metal plate 4, the thermosetting composite plate 14 laser-processed surface at the butt joint position facing each other overlap together, the metal plate 4 in the upper and lower, the thermosetting composite plate 14 in the middle, the overlap surface and the butt joint surface laying thickness 80 microns thick PA resin layer;

[0040] Step 4: If Figure 2 and Figure 6As shown, the first welding platen 15 of the clamping mechanism 5 applies an external force, and uses a continuous laser with a wavelength of 1064nm and a pulse width of 50ms to simultaneously perform rotational track welding on the upper and lower metal plates 4 and the thermosetting composite material plate 14 in a defocused state. The rotation amplitude r is 2.5mm, the distance d between the two amplitudes is 0.25mm, the track is 12mm×12mm, the horizontal straight line W is 4mm, and the longitudinal straight line L is 12mm, so that the resin added to the overlapping surface of the metal plate 4 and the two thermosetting composite material plates 14 and the resin added to the butt surface of the two thermosetting composite material plates 14 are fully melted, and the melted resin is bonded to the carbon fiber and metal of the thermosetting composite material plate 14 to form a joint, so that the two thermosetting composite material plates 14 are connected and firmly, and the welding joint is as shown in FIG. Figure 7 shown.

[0041] The beneficial effects of the present invention are as follows:

[0042] 1. The present application designs a laser guiding mechanism, which is combined with a laser to heat the metal plate at the joint of the composite material plate. Through the principle of heat conduction, the added resin is melted and cooled to room temperature to achieve the connection between the metal plate and the composite material plate, thereby achieving a more stable connection between the composite materials.

[0043] 2. The present application designs a combination of a clamping mechanism 5 and a pneumatic mechanism, which can realize automatic clamping and appropriate pressure on the composite material plate, and automated operation, saving manpower and improving work efficiency.

[0044] In conclusion, the thermosetting composite material butt welding device of the present invention has a simple structure, is easy to operate, has high welding efficiency, and has broad application prospects.

[0045] It should be noted that the above content only illustrates the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications all fall within the protection scope of the claims of the present invention.

Claims

1. A thermosetting composite material butt welding device, the thermosetting composite material butt welding device comprising a laser, a laser guiding mechanism, a metal plate (4), a supporting mechanism, a clamping mechanism (5) and a pneumatic mechanism, the supporting mechanism comprising a top seat (6), a base (9), a connecting support plate (7) and a supporting frame (12), the clamping mechanism (5) comprising a first welding pressure plate (15), a welding positioning groove (19), a second welding pressure plate (16), a telescopic seat (17), a bracket (18) and a sliding guide rail (20), the pneumatic mechanism comprising a first pneumatic device (8), a second pneumatic device (11), a pneumatic piston (10) and a third pneumatic device (13), the connecting support plate (7) being two, and being placed vertically and parallel, the upper end of which is fixedly connected to the top seat (6), the lower end of which is connected to the base (9), and the middle part of which is connected by the The support frame (12) is connected, the metal plate (4) is divided into two pieces, the support (18) and the telescopic seat (17) are respectively installed on the support frame (12), and the upper surfaces are kept in the same plane, the ends of the first pneumatic device (8), the second pneumatic device (11) and the third pneumatic device (13) are equipped with the pneumatic piston (10), the pneumatic piston (10) of the third pneumatic device (13) is fixed to the lower end of the telescopic seat (17), the sliding guide rail (20) is formed on the upper surface of the third pneumatic device, and is adapted to be installed with the groove on the lower surface of the telescopic seat (17), so that the telescopic seat (17) can slide back and forth on the upper surface of the third pneumatic device along the sliding guide rail (20), a second placement groove (1801) is formed above one end of the upper surface of the support (18), and the telescopic seat (17) A first placement groove (1701) is formed on the upper end of the surface opposite to the bracket (18); the first pneumatic device (8) and the second pneumatic device (11) are both two, which are respectively installed on the top seat (6) and the base seat (9), and the pneumatic pistons (10) at the end are opposite to each other; the first welding pressure plate (15) is two, one is fixedly connected to the pneumatic piston (10) at the end of the first pneumatic device (8), and the other is fixedly connected to the pneumatic piston (10) at the end of the second pneumatic device (11); the welding positioning groove (19) is formed on the first welding pressure plate (15), and the size is adapted to the metal plate (4); the two composite material plates to be butt-welded are respectively placed on the first placement groove (1701); The upper ends of the groove (1701) and the second placement groove (1801) are fixedly connected by a second welding platen (16), and thermoplastic resin is added to the butt surfaces of the two composite material plates, and the two plates are butt-jointed together. The metal plate (4) with a microstructured surface is laid on the upper and lower surfaces of the composite material plate, and the first pneumatic device (8), the second pneumatic device (11) and the third pneumatic device (13) are started, and the upper and lower first welding plates (15) move relative to each other until the metal plate (4) is placed in the welding positioning groove (19), and the composite material plate is limited in the vertical direction, and the telescopic seat (17) moves relative to the bracket (18) along the sliding guide rail (20).After limiting the composite material in the horizontal direction, the laser guiding mechanism is used to guide the laser to perform laser welding on the joint of the composite material; The laser guiding mechanism comprises a semi-mirror (1), three reflectors (2) and two scanning galvanometers (3); the two reflectors (2) and the two scanning galvanometers (3) are symmetrically mounted above and below the clamping mechanism (5), respectively; a semi-mirror (1) and a reflector (2) are mounted on one side of the clamping mechanism (5), respectively; laser light emitted by the laser is refracted into two beams of light by the semi-mirror (1); one beam of light passes through a reflector (2) and irradiates the scanning galvanometer (3) above the clamping mechanism (5); and one beam of light passes through two reflectors (2) in sequence and irradiates the scanning galvanometer (3) below the clamping mechanism (5), thereby laser welding is performed on the composite material plates to be butt-welded and mounted on the clamping mechanism (5); The laser is a fiber laser, a CO2 laser or a semiconductor laser; The thermoplastic resin is PA thermoplastic material, PC thermoplastic material, PPS thermoplastic material or PEEK thermoplastic material; The semi-transparent mirror (1), the reflective mirror (2) and the scanning galvanometer mirror (3) are glass lenses.

2. A butt welding method for a thermosetting composite material butt welding device according to claim 1, comprising the following steps: S1, using a short pulse laser to laser clean the upper and lower surfaces of the thermosetting composite material to be processed, removing the resin layer on the surface of the composite material, so that the carbon fiber of the composite material is fully exposed, and then enters S2; S2, using a short pulse laser to perform microstructural processing on the upper surface of the metal plate (4), and then enter S3; S3, using the clamping mechanism (5) to clamp the two thermosetting composite materials processed in step S1 in pairs, adding thermoplastic resin to the butt surfaces, and then starting the pneumatic mechanism to tightly butt the butt surfaces together, adding thermoplastic resin to the lower surface of the metal plate (4) processed by the microstructure in step S2 and laying it on the upper surface of the joint of the thermosetting composite materials, adding thermoplastic resin to the lower surface of the other metal plate (4) processed by the microstructure in step S2 and laying it on the lower surface of the joint of the thermosetting composite materials, and then entering S4; S4, start the laser guiding mechanism to guide the laser, the laser emitted by the laser is refracted into two beams of light through the semi-mirror (1), one beam of light passes through a reflector (2) and irradiates the scanning galvanometer (3) above the clamping mechanism (5), and then reflects to the metal plate (4) above the thermosetting composite material joint, and the other beam of light passes through two reflectors (2) in turn and irradiates the scanning galvanometer (3) below the clamping mechanism (5), and then reflects to the metal plate (4) below the thermosetting composite material joint, and the upper and lower metal plates (4) are simultaneously rotated and track welded by continuous laser in a defocused state until all the thermoplastic resins are fully melted, thereby completing the laser welding; The thickness of the added thermoplastic resin layer is less than 1 mm.

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