Laser optical module, laser welding head and laser welding method

Abstract

The present invention provides a laser optical module, a laser welding head and a laser welding method, and relates to the field of laser welding. The scheme adopted is: including a collimator, and also including: a beam splitter reflector, the structure of the beam splitter reflector is a regular tetrahedron, the bottom surface of the beam splitter reflector is coaxial with the collimator and perpendicular to the optical axis, and the four inclined surfaces of the beam splitter reflector can reflect the incident light beam into parallel light in four directions; a reflective component, the reflective component can reflect the four beams of parallel light reflected by the beam splitter reflector, and the angle θ of the four beams of parallel light after reflection is the same as that of the vertical direction; a focusing mirror, the focusing mirror can focus the four beams of parallel light reflected by the second reflecting component into four light spots, the centers of the four light spots can be centrally symmetrically distributed, and a wire tube through hole is provided at the center of the focusing mirror. The present invention can make the welding wire evenly heated and melted everywhere, and form a molten pool of regular shape, further improving the welding quality.

Description

Technical Field

[0001] The invention relates to the field of laser welding, and in particular to a laser optical module, a laser welding head and a laser welding method. Background Art

[0002] Laser welding can significantly improve welding quality, and compared with traditional welding technology, welding efficiency is also significantly improved. At present, the industry generally uses side-axis wire feeding welding. During the welding process, due to the influence of wire feeding angle, wire feeding position and light spot shape, the light wire cannot be accurately coupled, and the welding wire is heated unevenly, thereby reducing welding efficiency and welding quality.

[0003] In the prior art, in order to improve the quality of laser welding, coaxial wire feeding technology is used. Coaxial wire feeding refers to a wire feeding method in which the welding wire is fed to the welding area along the same axial direction as the laser beam through a specific device and process during the welding process. The welding wire is coaxial with the laser beam, which can ensure that all parts of the welding wire can be evenly affected by the laser energy when entering the welding area, avoiding local overheating or insufficient heating caused by wire feeding position deviation, making the welding wire melt more evenly, thereby improving the quality and stability of the weld.

[0004] Using the above technical solution, since the energy of Gaussian light decays exponentially with increasing distance from the center, on the one hand, this will make the molten pool appear deep in the center and shallow at the edge in the cross section, resulting in an irregular shape of the molten pool, affecting the fusion effect of the welding wire and the base material. On the other hand, the middle part of the welding wire melts faster. If the wire feeding speed is too fast or the laser energy is insufficient, the edge of the welding wire may not be able to melt in time and enter the molten pool in a solid form, affecting the quality and performance of the weld and causing defects such as slag inclusions and pores. Summary of the invention

[0005] In order to solve the technical problem of low welding quality in the above-mentioned prior art of coaxial wire feeding, the present invention provides a laser optical module, a laser welding head and a laser welding method, which can make the welding wire evenly heated and melted everywhere, and improve the shape of the molten pool, thereby further improving the welding quality.

[0006] In the first aspect, the present invention provides a laser optical module to solve the above technical problems, including a collimator and also including: a beam splitter reflector, wherein the structure of the beam splitter reflector is a regular quadrangular pyramid, the bottom surface of the beam splitter reflector is coaxial with the collimator and perpendicular to the optical axis, and the four inclined surfaces of the beam splitter reflector can reflect the incident light beam after passing through the collimator into parallel light in four directions; a reflection component, the reflection component can reflect the four beams of parallel light reflected by the beam splitter reflector, and the angle θ between the four beams of parallel light after reflection and the vertical direction is the same; a focusing mirror, the focusing mirror can focus the four beams of parallel light reflected by the reflection component into four light spots, the centers of the four light spots can be centrally symmetrically distributed, and a wire tube through hole is arranged at the center of the focusing mirror.

[0007] The present invention can form four light spots surrounding the welding wire at the material welding position through the cooperation of the beam splitter reflector, the reflection component and the focusing mirror, and the distribution of the four light spots is centrally symmetrical, so that the four directions of the welding wire can be heated from the outside to the inside and to the same extent, thereby ensuring that the welding wire is heated evenly and the light wire coupling is more precise. In addition, compared with one light spot in the prior art, the four light spots have a larger coverage area and the energy is dispersed, so that the bottom width of the molten pool is widened, the difference in the bottom depth is reduced, the cross-sectional shape of the molten pool is improved, and the welding quality is improved.

[0008] Furthermore, the reflection component includes a first reflection component and a second reflection component, the first reflection component includes four first reflectors, the first reflectors are arranged parallel to the corresponding inclined surfaces of the splitting reflector, and the spacing between the four first reflectors and the corresponding inclined surfaces is the same, the first reflectors can reflect the parallel light reflected by the corresponding inclined surfaces again, the second reflection component includes four second reflectors, the second reflectors are coaxially arranged with the corresponding first reflectors, the second reflectors can reflect the parallel light reflected by the corresponding first reflectors again, and the angle θ between the four beams of parallel light after reflection and the vertical direction is the same.

[0009] Furthermore, the second reflectors are respectively mounted on corresponding optical adjustment frames.

[0010] The present invention can adjust the angle of the second reflector by using an optical adjustment frame, change the angle θ between the four parallel light beams and the vertical direction, and further adjust the spacing between adjacent light spots, change the coverage of the four light spots, and meet the needs of corresponding welding accuracy.

[0011] Furthermore, the angle between the inclined surface and the bottom surface of the beam splitting reflector is 45°, and two of the four parallel light beams reflected by the first reflection component are distributed in the vertical direction of the optical axis, and two are distributed in the horizontal direction of the optical axis. The right-angle optical adjustment frame can be adjusted within the range of 45°±α.

[0012] The present invention can generate two beams of light in the vertical direction and two beams of light in the horizontal direction, which is convenient for the structure layout of the laser head and is convenient for use, installation and adjustment.

[0013] Furthermore, the focusing mirror is connected to a defocus adjustment mechanism, and the defocus adjustment mechanism can adjust the position of the focusing mirror in the vertical direction.

[0014] The present invention can change the diameter of the light spot by adjusting the position of the focusing mirror, and is suitable for welding materials of different thicknesses.

[0015] Furthermore, it also includes a flat top light shaping component, which includes an aspheric plano-concave lens and an aspheric plano-convex lens. The light beam passes through the aspheric plano-concave lens and then enters the aspheric plano-convex lens. The aspheric plano-concave lens and the aspheric plano-convex lens are both placed coaxially with the collimator.

[0016] The present invention shapes the Gaussian beam into a flat-top light through a flat-top light shaping component, which can concentrate the laser energy in the effective processing area, improve energy utilization, and at the same time make the laser energy evenly distributed in the spot area, further improving the welding quality.

[0017] In the second aspect, the present invention also provides a laser welding head, including a shell and a wire feeding tube, and also includes the above-mentioned laser optical module, the wire feeding tube passes through the wire tube through hole on the focusing lens, the wire feeding tube extends out of the shell and a wire feeding nozzle is installed at the bottom end of the wire feeding tube, and welding wire is arranged in the wire feeding tube.

[0018] Furthermore, the defocus adjustment mechanism includes a motor and a lead screw connected to each other, the motor is arranged on the housing, the lead screw is rotatably arranged on the housing, a slide is arranged on the lead screw, the slide is connected to the housing via a slide rail, and the focusing lens is arranged on the slide.

[0019] Furthermore, it also includes a mounting seat ring, the shell is divided into an upper shell and a lower shell, the mounting seat ring is provided with an upper connecting part, a mounting part and a lower connecting part in sequence from top to bottom, the upper connecting part is threadedly connected to the upper shell, the lower connecting part is threadedly connected to the lower shell, the inner wall of the mounting part is provided with a supporting ring, and four groups of the optical adjustment frames are evenly arranged on the supporting ring.

[0020] In a third aspect, the present invention further provides a laser welding method, using the above-mentioned laser welding head, comprising the following steps: According to the thickness of the material and / or the welding accuracy, the spot diameter and the spot position are adjusted by adjusting the optical adjustment frame and / or the defocus adjustment mechanism.

[0021] It can be seen from the above technical solutions that the present invention has the following advantages: The present invention provides a laser optical module, a laser welding head and a laser welding method. Through the cooperation of a beam splitting reflector, a reflection component and a focusing mirror, four light spots surrounding a welding wire can be formed at a material welding position, and the distribution of the four light spots is centrally symmetrical, so that the welding wire can be heated from the outside to the inside and to the same extent in four directions, ensuring that the welding wire is heated evenly, and the light wire coupling is more accurate. In addition, compared with one light spot in the prior art, the four light spots have a larger coverage area, and the energy is dispersed, so that the bottom width of the molten pool is widened, the difference in the bottom depth is reduced, the cross-sectional shape of the molten pool is improved, and the welding quality is improved; the second light spot can be adjusted by using an optical adjustment frame The angle of the reflector changes the angle θ between the four parallel light beams and the vertical direction, thereby adjusting the spacing between adjacent light spots and changing the coverage of the four light spots to meet the needs of corresponding welding accuracy; it can generate two beams of light in the vertical direction and two beams of light in the horizontal direction, which is convenient for the structural layout of the laser head and is easy to use, install and adjust; by adjusting the position of the focusing mirror, the size of the light spot diameter can be changed, which is suitable for welding materials of different thicknesses; the Gaussian beam is shaped into a flat-top light through a flat-top light shaping component, which can concentrate the laser energy in the effective processing area and improve the energy utilization rate. At the same time, it can make the laser energy evenly distributed in the light spot area, further improving the welding quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solution of the present invention, the accompanying drawings required for use in the description will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0023] Figure 1 It is a structural schematic diagram of a specific implementation mode 1 of the present invention.

[0024] Figure 2 It is a structural schematic diagram of the beam splitter reflector in the first specific implementation mode of the present invention.

[0025] Figure 3 This is a schematic diagram of focusing four obliquely incident parallel light beams into four light spots in a first specific implementation mode of the present invention.

[0026] Figure 4 It is a schematic diagram of the assembly structure of the wire feeding tube and the focusing lens in the second specific implementation mode of the present invention.

[0027] Figure 5 The combination state of the light spots in the third specific embodiment of the present invention is Figure 1 .

[0028] Figure 6 The combination state of the light spots in the third specific embodiment of the present invention is Figure 2 .

[0029] In the figure, 1, optical fiber; 2, collimating lens; 3, flat-top light shaping component; 301, aspheric plano-concave lens; 302, aspheric plano-convex lens; 4, beam splitter reflector; 5, reflection component; 501, first reflector; 502, second reflector; 6, focusing lens; 7, welding wire; 8, wire feeding tube; 9, nozzle. DETAILED DESCRIPTION

[0030] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical scheme of the present invention will be clearly and completely described below in conjunction with the drawings in this specific embodiment. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of them. Based on the embodiments in this patent, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this patent. Specific implementation method 1 like Figure 1 As shown, this specific embodiment provides a laser optical module, which includes a collimator 2, a beam splitter reflector 4, a reflection component 5 and a focusing mirror 6 in sequence along the laser propagation direction. The structure of the beam splitter reflector 4 is a regular quadrangular pyramid. The bottom surface of the beam splitter reflector 4 is coaxial with the collimator 2 and perpendicular to the optical axis. The four inclined surfaces of the beam splitter reflector 4 can reflect the incident light beam after passing through the collimator 2 into parallel light in four directions; the reflection component 5 can reflect the four beams of parallel light reflected by the beam splitter reflector 4, and the angle θ between the four beams of parallel light after reflection and the vertical direction is the same; the focusing mirror 6 can focus the four beams of parallel light reflected by the reflection component 5 into four light spots, the centers of the four light spots are evenly distributed on a circle with a radius of r, and are centrally symmetrically distributed. A wire tube through hole is provided at the center of the focusing mirror 6, and the circle with a radius of r is coaxial with the focusing mirror 6.

[0032] This specific implementation method decomposes the original laser beam into four independent beams through the cooperation of the beam splitter reflector 4, the reflective component 5 and the focusing mirror 6. The reflective component adjusts the spatial divergence angle and position of each beam, and then forms four light spots with central symmetrical distribution around the welding wire through the focusing mirror. It has the technical effects of enhanced geometric symmetry, full coverage of the energy field and improved freedom of dynamic regulation. This has the following favorable effects on welding quality: First, the thermal field symmetry and uniform heating, the radial covering heating mode of the four light spots on the welding wire, forms an isotropic temperature field when the material melts, and the energy flux applied by each light spot is equal, so that The four-way heat conduction rate of the welding wire tends to be consistent, which effectively avoids the problem of uneven melting of the welding wire caused by heat source bias in traditional single-spot welding; secondly, the morphology and dynamic behavior of the molten pool are improved. The total coverage area of ​​the four spots is many times that of a single spot. The expansion of the energy distribution range enhances the lateral heat diffusion at the bottom of the molten pool, greatly increases the width of the molten pool, and makes the weld joint surface wider. Especially for welding of dissimilar materials (such as steel-aluminum), the reliability of the interface metallurgical bonding is significantly improved, and the depth difference of the molten pool can be reduced. In single-spot welding, the laser energy is extremely high near the axis, resulting in the depth of the molten pool center being much greater than that of the edge (the depth difference can reach 2.0 mm), while in four-spot welding, the energy peak value of each spot superimposed is dispersed to the surroundings, and the energy flux density in the axis area slows down, so that the depth fluctuation range of the bottom of the molten pool is narrowed to ±0.3 mm, presenting a uniform shallow dish-shaped cross-section, which is crucial for the penetration control of thin plate welding and is conducive to precision welding; thirdly, the light-wire coupling accuracy is improved. On the one hand, the dynamic tracking tolerance is enhanced. When the welding wire is slightly offset due to vibration or wire feeding error, the annular heating zone of the four-spot can provide a larger spatial tolerance (the displacement compensation distance can be up to 3 times that of the single-spot). The spatial robustness of heat input avoids the energy coupling failure caused by the misalignment of the light wire, and the probability of arc interference is reduced. On the other hand, the linearization of the heat accumulation process. In single-spot welding, the welding wire instantly absorbs high-density energy, which is easy to cause surface vaporization or spattering. The four-spot extends the response time of the material phase change through the gradual heating mechanism (periphery → center), which makes the temperature rise slope gentle, improves the laser energy conversion efficiency, and reduces the number of spatter particles.

[0033] like Figure 1As shown, in this specific embodiment, in order to change the propagation direction of the light beam and obtain four beams of parallel light with the same angle with the vertical direction, the reflection component 5 includes a first reflection component and a second reflection component, the first reflection component includes four first reflectors 501, the first reflectors 501 are arranged in parallel with the corresponding inclined surfaces of the splitting reflector 4, and the four first reflectors 501 are spaced the same distance from the corresponding inclined surfaces, the first reflectors 501 can reflect the parallel light reflected by the corresponding inclined surfaces again, the second reflection component includes four second reflectors 502, the second reflectors 502 are coaxially arranged with the corresponding first reflectors 501, the second reflectors 502 can reflect the parallel light reflected by the corresponding first reflectors 501 again, and the angle θ of the four reflected parallel light beams with the vertical direction is the same.

[0034] like Figure 1 As shown, since different welding accuracies require different weld widths, in order to meet the requirements of welding accuracy and improve the flexibility of the use of this module, the second reflectors 502 are respectively installed on corresponding optical adjustment frames, and the optical adjustment frames are two-dimensional adjustment frames, which can adjust the pitch angle (with the X-axis as the rotation axis) and the tilt angle (with the Y-axis as the rotation axis) of the second reflector 502, change the propagation direction of the light beam, and achieve a change in the size of the angle θ between the corresponding reflected light beam and the vertical direction, thereby changing the position of the corresponding light spot, so that the radius r of the circle where the center of the four light spots is located is adjusted. , and obtain different weld widths; specifically, the corresponding optical adjustment frame can adjust the angle between the two light beams (C and D) distributed in the horizontal direction of the optical axis after being reflected by the corresponding second reflector 502 and the vertical direction (so that the second reflector 502 corresponding to the light beams C and D rotates with the Y axis as the rotation axis), and the corresponding optical adjustment frame can adjust the angle between the two light beams (A and B) distributed in the vertical direction of the optical axis after being reflected by the corresponding second reflector 502 and the vertical direction (so that the second reflector 502 corresponding to the light beams A and B rotates with the X axis as the rotation axis).

[0035] Since materials of different thicknesses require different molten pool depths, in order to be suitable for welding materials of different thicknesses, in this specific embodiment, the focusing mirror 6 is connected to a defocus adjustment mechanism, and the defocus adjustment mechanism can adjust the position of the focusing mirror 6 in the vertical direction. By adjusting the defocus adjustment mechanism to change the defocus amount y, light spots of different diameters are obtained, and then molten pools of different depths are obtained to meet the welding needs of materials of various thicknesses.

[0036] like Figure 2As shown, further, to facilitate the layout of the laser, in this specific embodiment, the angle between the inclined surface and the bottom surface of the beam splitter reflector 4 is 45°, and among the four beams of parallel light reflected by the first reflection component, two beams are distributed in the vertical direction of the optical axis (A and B), and two beams are distributed in the horizontal direction of the optical axis (C and D), and the right-angle optical adjustment frame can be adjusted within the range of 45°±α, and the second reflector 502 is installed at an angle of 45° relative to the optical axis; after such arrangement, the laser head has a compact structure, and is convenient to use, install and adjust.

[0037] like Figure 1 As shown, in order to further improve the welding quality, this specific embodiment also includes a flat top light shaping component 3, the flat top light shaping component 3 includes an aspheric plano-concave lens 301 and an aspheric plano-convex lens 302, the light beam passes through the aspheric plano-concave lens 301 and enters the aspheric plano-convex lens 302, the aspheric plano-concave lens 301 and the aspheric plano-convex lens 302 are both coaxially placed with the collimator 2; the Gaussian beam is shaped into a flat top light by the flat top light shaping component 3, the laser energy can be concentrated in the effective processing area, the energy utilization rate can be improved, and the laser energy can be distributed more evenly in each spot area, so that the welding wire 7 is heated more evenly, the depth difference at the bottom of the molten pool is further reduced, and the welding quality is further improved.

[0038] In this specific embodiment, four beams of parallel light are deflected outward along the center, and form four light spots after being incident on the focusing mirror 6. After the defocus is adjusted by the defocus adjustment mechanism, the centers of the defocused light spots are evenly distributed on a circle with a radius of r. The relationship between the radius r and θ of the circle is shown in the following formula:

[0039] The diameter D of the focused light spot is:

[0040] The size of each spot after defocusing D' is:

[0041] Where λ is the laser wavelength, f is the focal length of the focusing lens, and d is the ratio of the light intensity at the Gaussian beam waist radius to the peak light intensity. The radius when e is the base of the natural logarithm, which is approximately equal to 2.71828.

[0042] By adjusting the angle θ between the light beam and the vertical direction and the defocus amount y, different sizes of spot diameters D' and circular radius r can be obtained, so that the combination of the four spots can be adjusted. For example, increasing the angle θ can increase the spacing between adjacent spots and increase the coverage range; reducing the defocus amount y can reduce the diameter D' of each spot after defocusing, thereby achieving high-precision and narrow weld welding.

[0043] The working process of this laser optical module is: After the optical fiber 1 emits a laser beam, a parallel light beam is generated by the collimator 2. The parallel light beam is converted into a flat-top beam by the flat-top light shaping component 3. The flat-top beam reflects four parallel light beams after passing through the beam splitter reflector 4. The four parallel light beams after reflection are reflected by the corresponding first reflector 501 to change the propagation path. The four light beams are evenly distributed. There are two light beams A and B in the vertical direction and two light beams C and D in the horizontal direction. After being reflected by the second reflector 502, the propagation path is further changed to become four parallel light beams with an angle of θ with the vertical direction. The area surrounded by the reflected light beams is a square. The four reflected light beams are deflected outward along the center respectively, no longer emitted vertically, and obliquely incident on the focusing mirror 6. After passing through the focusing mirror 6, four light spots are formed on the surface of the workpiece. The four light spots are evenly distributed on a circle with a radius of r. The size of r is controlled by adjusting the size of the above-mentioned angle θ. Among them, if θ=0°, the four light beams are focused to a point to form a light spot. Specific implementation method 2 This specific embodiment provides a laser welding head, including a shell and a wire feeding tube 8, and also includes the laser optical module of specific embodiment one, the wire feeding tube 8 passes through the wire tube through hole on the focusing lens 6, the wire feeding tube 8 extends out of the shell and a wire feeding nozzle 9 is installed at the bottom end of the wire feeding tube 8, and a welding wire 7 is arranged in the wire feeding tube 8.

[0045] In this specific embodiment, the defocus adjustment mechanism includes a motor and a screw connected to each other, the motor is arranged on the shell, the screw is rotatably arranged on the inner wall of the shell, a slide is arranged on the screw, the slide is connected to the inner wall of the shell through a slide rail, and the focusing mirror 6 is arranged on the slide; it can be understood that the defocus adjustment mechanism can also adopt a gear rack transmission mechanism.

[0046] In this specific embodiment, it also includes a mounting seat ring, the shell is divided into an upper shell and a lower shell, the mounting seat ring is provided with an upper connecting part, a mounting part and a lower connecting part in sequence from top to bottom, the upper connecting part is threadedly connected to the upper shell, the lower connecting part is threadedly connected to the lower shell, a supporting ring is provided on the inner wall of the mounting part, four groups of the optical adjustment frame are evenly arranged on the end surface of the supporting ring, four groups of limiting grooves are evenly arranged on the supporting ring, spring pins are provided on the groove walls of the limiting grooves, and limiting holes are provided at corresponding positions of the optical adjustment frame shell, the spring pins can extend into the limiting holes, and the optical adjustment frame can be stuck in the limiting grooves.

[0047] In this specific embodiment, in order to realize automatic adjustment, the optical adjustment frame adopts an electric adjustment frame of the model 01OS series, which is a product purchased from the market. It adopts a stepper motor and a worm gear pair to realize the two-dimensional angle adjustment of the lens. The stepper motor is electrically connected to the control system of the equipment, and the motor of the defocus adjustment mechanism adopts a servo motor, which is also electrically connected to the control system of the equipment. Specific implementation method three This specific embodiment provides a laser welding method, which adopts the laser welding head of specific embodiment 2, and includes the following steps: according to the thickness of the material and / or the welding accuracy, by adjusting the optical adjustment frame and / or the defocus adjustment mechanism, the spot diameter and the spot position are adjusted, and then the combination of the four spots is changed to adjust the welding area and the welding pool depth.

[0049] Specifically, Figure 6 As shown in the figure, when the material is thicker, the depth of the molten pool is greater, and a larger diameter spot is required. By increasing the defocus amount y, a larger diameter D' spot can be obtained; if there are higher requirements for welding accuracy (a narrower weld is required), the corresponding optical adjustment frame can be adjusted to reduce the angle between the light beam and the vertical direction, so as to reduce the spacing between adjacent light spots, reduce the coverage area of ​​the four light spots, and narrow the weld; as shown in the figure, Figure 5 As shown, if the material is thin, it is necessary to avoid burn-through caused by a large molten pool depth, reduce the maximum defocus y, and reduce the spot diameter D'. At the same time, the angle θ between the light beam and the vertical direction can be further adjusted through the optical adjustment frame to reduce the coverage area of ​​the four spots and narrow the weld.

[0050] During adjustment, the optical adjustment frame and the defocus adjustment mechanism can be manually adjusted, and the optimal parameters can be determined through multiple trial welding. However, in this specific embodiment, in order to improve efficiency, the corresponding spot diameters D' and circular radii r of different welding workpieces under different welding accuracy levels are stored in the control system of the equipment in advance. During welding, the operator inputs the corresponding type of welding workpiece and welding accuracy requirements into the control system, and the control system determines the corresponding spot diameter D' and circular radius r, and then calculates the corresponding angle θ and defocus amount y according to the formula, and controls the optical adjustment frame and the defocus adjustment mechanism to move in place. This way, the adjustment is accurate and the adjustment efficiency can be greatly improved, avoiding the impact of manual adjustment errors.

[0051] From the above specific implementations, it can be seen that the present invention has the following beneficial effects: 1. Through the cooperation of the beam splitter reflector 4, the reflective assembly and the focusing mirror 6, four light spots surrounding the welding wire 7 can be formed at the material welding position, and the distribution of the four light spots is centrally symmetrical, so that the welding wire 7 can be heated from the outside to the inside and to the same extent in four directions, ensuring that the welding wire 7 is heated evenly, and the light wire coupling is more accurate. In addition, compared with one light spot in the prior art, the four light spots have a larger coverage area, and the energy is dispersed, so that the bottom width of the molten pool is widened, the bottom depth difference is reduced, the cross-sectional shape of the molten pool is improved, and the welding quality is improved; 2. By using an optical adjustment frame, the angle of the second reflector 502 can be adjusted to change the angle θ between the four parallel light beams and the vertical direction, thereby adjusting the spacing between adjacent light spots and changing the coverage of the four light spots to meet the needs of corresponding welding accuracy; 3. It can generate two beams of light in the vertical direction and two beams in the horizontal direction, which is convenient for the laser head structure layout, and is easy to use, install and adjust; 4. By adjusting the position of the focusing mirror 6, the spot diameter can be changed, which is suitable for welding materials of different thicknesses; 5. The Gaussian beam is shaped into a flat-top beam by the flat-top beam shaping component 3, so that the laser energy can be concentrated in the effective processing area, improving the energy utilization rate, and at the same time, the laser energy can be evenly distributed in the spot area, further improving the welding quality.

[0052] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A laser optical module, comprising a collimator lens (2), characterized in that: Also includes: A beam splitter reflector (4), the structure of the beam splitter reflector (4) being a regular quadrangular pyramid, the bottom surface of the beam splitter reflector (4) being coaxial with the collimator (2) and perpendicular to the optical axis, and the four inclined surfaces of the beam splitter reflector (4) being capable of reflecting an incident light beam after passing through the collimator (2) into parallel light in four directions; A reflection component (5), the reflection component (5) being capable of reflecting the four beams of parallel light reflected by the beam splitting reflector (4), and the angles θ between the four beams of parallel light after reflection and the vertical direction are the same; A focusing mirror (6), wherein the focusing mirror (6) is capable of focusing four beams of parallel light reflected by the reflection component (5) into four light spots, the centers of the four light spots being able to be centrally symmetrically distributed, and a wire tube through hole is provided at the center of the focusing mirror (6).

2. The laser optical module according to claim 1, characterized in that: The reflection component (5) comprises a first reflection component and a second reflection component, the first reflection component comprising four first reflection mirrors (501), the first reflection mirrors (501) being arranged in parallel with the corresponding inclined surfaces of the beam splitting reflection mirror (4), and the four first reflection mirrors (501) being spaced the same distance from the corresponding inclined surfaces, the first reflection mirrors (501) being capable of re-reflecting parallel light reflected by the corresponding inclined surfaces, and the second reflection component comprising four second reflection mirrors (502), the second reflection mirrors (502) being arranged coaxially with the corresponding first reflection mirrors (501), the second reflection mirrors (502) being capable of re-reflecting parallel light reflected by the corresponding first reflection mirrors (501), and the angles θ between the four beams of reflected parallel light and the vertical direction being the same.

3. The laser optical module according to claim 2, characterized in that: The second reflecting mirrors (502) are respectively mounted on corresponding optical adjustment frames.

4. The laser optical module according to claim 3, characterized in that: The angle between the inclined surface and the bottom surface of the beam splitting reflector (4) is 45°; of the four beams of parallel light reflected by the first reflective component, two are distributed in the vertical direction of the optical axis and two are distributed in the horizontal direction of the optical axis; the right-angle optical adjustment frame can be adjusted within a range of 45°±α.

5. The laser optical module according to claim 3, characterized in that: The focusing mirror (6) is connected to a defocus adjustment mechanism, and the defocus adjustment mechanism is capable of adjusting the position of the focusing mirror (6) in the vertical direction.

6. The laser optical module according to claim 5, characterized in that: It also comprises a flat top light shaping component (3), the flat top light shaping component (3) comprising an aspheric plano-concave lens (301) and an aspheric plano-convex lens (302), the light beam passing through the aspheric plano-concave lens (301) is incident upon the aspheric plano-convex lens (302), the aspheric plano-concave lens (301) and the aspheric plano-convex lens (302) being both coaxially arranged with the collimating lens (2).

7. A laser welding head, comprising a housing and a wire feeding tube (8), characterized in that: It also includes the laser optical module as claimed in claim 6, wherein the wire feeding tube (8) passes through the focusing lens (6), the wire feeding tube (8) extends out of the shell and a wire feeding nozzle (9) is installed at the bottom end of the wire feeding tube (8), and a welding wire (7) is arranged in the wire feeding tube (8).

8. The laser welding head according to claim 7, characterized in that: The defocus adjustment mechanism comprises a motor and a lead screw connected to each other, the motor being arranged on the housing, the lead screw being rotatably arranged on the housing, a slide being arranged on the lead screw, the slide being connected to the housing via a slide rail, and the focusing mirror (6) being arranged on the slide.

9. The laser welding head according to claim 8, characterized in that: It also includes a mounting seat ring, the shell is divided into an upper shell and a lower shell, the mounting seat ring is provided with an upper connecting part, a mounting part and a lower connecting part in sequence from top to bottom, the upper connecting part is threadedly connected to the upper shell, the lower connecting part is threadedly connected to the lower shell, the inner wall of the mounting part is provided with a supporting ring, and four groups of the optical adjustment frames are evenly arranged on the supporting ring.

10. A laser welding method, characterized in that: Using the laser welding head as claimed in claim 9, comprising the following steps: According to the thickness of the material and / or the welding accuracy, the spot diameter and the spot position are adjusted by adjusting the optical adjustment frame and / or the defocus adjustment mechanism.

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