Welding surface shaping laser welding machine and laser welding method

Abstract

The invention relates to the technical field of laser welding, in particular to a welding face shaping laser welding machine and a laser welding method.The equipment comprises a rack, the rack is provided with a shaping lifting base, a high-frequency collision shaping device, a laser emitter with a high-speed galvanometer and a welding pressing base, and the high-frequency collision shaping device is located above the shaping lifting base; according to the laser welding device, two welding parts are collided at high frequency, so that the welding surfaces of the workpieces are shaped, then laser welding is used for welding under a certain pressure, dust is not generated, and the laser welding device has the advantages of being simple in structure, convenient to operate and high in practicability. The laser welding device is not limited by the shape of a welding piece, the welding quality is good, laser is distributed at multiple points during high-frequency scanning during welding, accordingly, the multiple points are heated and welded at the same time, the overall welding speed is increased, the heating time of a single point is delayed, and the welding quality is improved.

Description

Technical Field

[0001] The invention relates to the technical field of laser welding, and in particular to a welding surface shaping laser welding machine and a laser welding method. Background Art

[0002] Laser welding is an efficient and precise welding method that uses a high-energy-density laser beam as a heat source. Taking heat conduction laser welding as an example, the surface to be processed is heated by laser radiation, and the surface heat diffuses to the inside through heat conduction, melting the workpiece and forming a specific molten pool.

[0003] However, laser welding has high requirements on the dimensional accuracy of welded parts, generally requiring the dimensional error to be within 0.2mm. However, during the molding process of plastics, due to the molding process, mold and structural design, raw materials and machines, etc., large dimensional errors or even certain deformations may occur on the welding surface. This makes it impossible to directly laser weld the product, and the surface quality of some welding surfaces may not meet the requirements, which also brings obstacles to laser welding.

[0004] The inventor disclosed a plastic shaping laser welding process in Chinese invention patent 2019105017872, which uses vibration friction welding to perform vibration friction cutting on the welding surface. The friction cutting causes the welding surface that contacts first to be cut and melted and extruded, gradually reducing the gap between the two welded parts to within the required range, and making part or all of the welding surfaces reliably connected, and then using a laser to perform laser welding on the welding surface.

[0005] However, in actual use, the inventors found that this method would generate dust during vibration and friction, and the dust would remain between the two welded parts, affecting the light transmittance and appearance of the finished product. In addition, some welded parts are restricted by the shape of the welding surface, making it impossible to use vibration friction welding for cutting.

[0006] In addition, power density is one of the key parameters in laser welding. Higher power density is generally used for material removal processing, such as drilling, cutting, and engraving. It can heat the surface to boiling point within microseconds, producing a large amount of vaporization; for lower power density, it takes several milliseconds for the surface temperature to reach the boiling point. Before the surface vaporizes, the bottom layer reaches the melting point, which is easy to form a good molten weld. Therefore, in conduction laser welding, the power density is in the range of 10 4 ~~10 6 W / CM 2 , which means that laser welding can only use low power density lasers, resulting in longer welding time. On the other hand, when laser welding, especially high power density laser welding, when the laser beam is projected onto the weld, it will cause high temperature gradient and high stress gradient accompanied by local high temperature, causing micro cracks or large internal stress at the weld, affecting the welding quality. Summary of the invention

[0007] The purpose of the present invention is to provide a welding surface shaping laser welding machine and a laser welding method to address the deficiencies of the prior art. The present invention causes two welding parts to collide at high frequency to shape the welding surface of the workpieces, and then uses laser welding. No dust is generated, and it is not limited by the shape of the welding parts. The welding quality is good. During welding, the laser performs high-frequency scanning distributed at multiple points, thereby heating and welding multiple points at the same time, thereby improving the overall welding speed, delaying the heating time of a single point, and improving the welding quality.

[0008] The technical solution adopted by the present invention to solve its technical problems is: a welding surface shaping laser welding machine, including a frame, the frame is provided with a shaping lifting seat for fixing a first welding part, a high-frequency collision shaping device for driving a second welding part to collide with the first welding part at high frequency in a vertical direction to shape the welding surface of the workpiece, a laser emitter with a high-speed galvanometer, and a liftable welding clamping seat, the high-frequency collision shaping device is located above the shaping lifting seat, the frame is provided with a translation mechanism for translating the shaping lifting seat to the bottom of the welding clamping seat, and the laser emitter is located above the welding clamping seat.

[0009] Among them, the high-frequency collision shaping device includes a driving seat and a vibrating head, both ends of the driving seat are connected to the frame, an excitation coil is arranged in the middle of the driving seat, and the excitation coil is provided with an armature that can vibrate up and down, and the armature is fixedly connected to the vibrating head, and a plurality of spring vibration seats are respectively arranged on both sides of the vibrating head, each of the spring vibration seats is connected to a vibration spring, and the vibration spring includes a fixed end and a vibrating end, and the fixed end and the vibrating end both extend in the vertical direction and are arranged in parallel, and the fixed end and the vibrating end are connected by a plurality of spring leaves, and the vibrating end of the vibration spring is fixedly connected to the spring vibration seat, and the fixed end of the vibration spring is fixedly connected to the driving seat.

[0010] Preferably, a plurality of groups of excitation coils arranged in a horizontal direction are provided in the middle of the driving seat, each group of the excitation coils is provided with an armature that can vibrate up and down, and the vibration spring is located on the same side of the corresponding spring vibration seat.

[0011] Preferably, the excitation coils are in three groups, and four spring vibration seats are respectively provided on both sides of the vibration head.

[0012] Preferably, the fixed end of the vibration spring is connected to the driving seat via a spring fixing seat, and the spring fixing seat located on the same side of the driving seat is fixedly connected via a stabilizing block.

[0013] Preferably, a fixture mounting hole is provided on a side of the vibration head close to the shaping lifting seat, and reinforcing ribs are provided between two sides of the vibration head.

[0014] The present invention also provides a laser welding method, which uses the laser transmitter with a high-speed galvanometer for laser welding. During welding, the laser formed by the laser passes through the high-speed galvanometer to form a light spot at the weld between the first welding part and the second welding part. The laser is a high-power laser, and a section of the weld along its extension direction is the welding area. The light spot scans point by point in the welding area at a high frequency and cycles through multiple scans, so that the temperature of each point in the welding area gradually increases to melting.

[0015] Preferably, the welding surface is shaped before welding. During the shaping, the second welding part is firstly collided and squeezed with the first welding part at a high frequency within a small distance. The amplitude of the second welding part is 0.2-2mm, and the vibration frequency is 50-1000Hz. The heat generated by the collision causes the surface at the collision to melt and then deform, so that the shape of the workpiece welding surface meets the welding requirements, and then the laser emitter is used for laser welding.

[0016] Preferably, the first welding part and the second welding part are made of plastic, and each point is marked as P in turn when the spot is scanned once. i , 0<i≤n, the number of cycles of the light spot scanning is m, and the light spot is at point P for the jth time i The heat generated during the residence is Q ij , click P i The heat dissipated from the end of the j-1 scan to the end of the j scan is q ij The heat of the workpiece burning through is Q max ,

[0017] Preferably, the light spot is at point P for the jth time i The dwell time is t ij , t ij ≥0, 10<m<20, the laser is a continuous laser or a pulsed laser, the power of the laser beam is 50-500W, the length of the welding area when the spot scans once in a cycle is 5cm-20cm, and the time for the spot to complete a scan is 100ms-400ms.

[0018] Preferably, during welding, the focal position of the laser beam is 2-10 mm below the welding surface, and the radius of the spot is 0.5-3 mm.

[0019] Preferably, the welding surfaces of the first welding part and the second welding part are provided with a plurality of welding points, and the welding points protrude from the welding surfaces. Pre-welding is performed after shaping. During pre-welding, the second welding part continues to collide and squeeze the first welding part at a high frequency within a small distance, and the second welding part continues to contact the first welding part until part or all of the welding surfaces are in reliable contact.

[0001] The beneficial effects of the present invention are as follows: 1. It provides a device capable of realizing high-frequency collision and extrusion of two plastic workpieces in a vertical direction for shaping, and then laser welding.

[0002] 2. Use multiple excitation coils to synchronously drive multiple armatures to vibrate synchronously, making the vibration of the vibration head more stable and can be used for larger welding parts.

[0020] 3. A welding method is provided, which first performs shaping by high-frequency collision extrusion and then performs laser welding. The method has good welding quality and can be applied to welding parts of various structures without generating dust, thereby improving the light transmittance of the welding parts.

[0021] 4. High-power laser can be used for welding. In the prior art, the laser power is relatively low during welding, otherwise the workpiece will burn through due to excessive local temperature.

[0022] 5. The single-point welding time is long and the temperature rise is stable during welding, which reduces the temperature gradient and stress gradient, makes the internal stress of the weld smaller, and improves the welding quality. However, in the prior art, melting welding is performed on one point before the next point, resulting in a short single-point welding time, fast temperature rise, large temperature gradient and stress gradient, large internal stress of the weld, and easy generation of micro cracks.

[0023] 6. When the weld is cooling, the laser can still be irradiated there. By adjusting the power or irradiation time, the cooling speed can be slowed down to further reduce the internal stress of the weld.

[0024] 7. The welding speed is fast. Due to the use of high-power laser, it can weld a large area of ​​welding area at a high frequency, thereby improving the overall welding speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of the welding surface shaping laser welding machine of the present invention.

[0026] Figure 2 It is a schematic structural diagram of the high-frequency collision shaping device of the present invention.

[0027] Figure 3 It is a structural schematic diagram of the vibration head, the excitation coil and the armature of the present invention.

[0028] Figure 4It is a structural schematic diagram of the vibrating head of the present invention.

[0029] Figure 5 It is a schematic diagram of the shaping lifting seat and translation mechanism structure of the present invention.

[0030] Figure 6 It is a schematic diagram of the laser welding method of the present invention when the light spot is scanned.

[0031] Figure 7 It is a schematic diagram of an implementation method of the welding area during spot scanning in the laser welding method of the present invention.

[0032] Figure 8 It is a schematic diagram of another implementation of the welding area during spot scanning in the laser welding method of the present invention.

[0033] Description of reference numerals: 1——Frame 2——Shaping lifting seat 3——High frequency collision shaping device 31——Drive seat 32——Vibration head 321——Spring vibration seat 322——Reinforcement rib 33——Excitation coil 34——armature 35——vibration spring 351——Fixed end 352——Vibration end 353——Reed 36——Spring fixing seat 37——Stabilizer Block 4——Laser Transmitter 5——Welding clamping seat 6——Translation mechanism P i ——The points distributed during the light spot scanning, i = 1, 2, 3, ..., n S1 - first welding area S2 - second welding area. DETAILED DESCRIPTION

[0034] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, but the implementation scope of the present invention is not limited thereto.

[0035] Embodiment 1.

[0036] like Figure 1As shown in the figure, the welding surface shaping laser welding machine of this embodiment includes a frame 1, the frame 1 is provided with a shaping lifting seat 2 for fixing the first welding piece, a high-frequency collision shaping device 3 for driving the second welding piece to collide with the first welding piece in the vertical direction at high frequency to shape the welding surface of the workpiece, a laser emitter 4 with a high-speed galvanometer, and a liftable welding clamping seat 5. The high-frequency collision shaping device 3 is located above the shaping lifting seat 2, the frame 1 is provided with a translation mechanism 6 for translating the shaping lifting seat 2 to the bottom of the welding clamping seat 5, and the laser emitter 4 is located above the welding clamping seat 5. The first welding piece is fixed to the shaping lifting seat 2 by a fixture or a mold, and the second welding piece is fixed to the high-frequency collision shaping device 3 by a fixture or a mold. It should be noted that the first welding piece and the second welding piece can be multiple identical parts respectively, so as to realize simultaneous shaping and welding of multiple parts.

[0037] When in use, the high-frequency collision shaping device 3 is first used to drive the second welding part to vibrate up and down in the vertical direction, so that the second welding part collides and squeezes the first welding part, and the heat generated by the high-frequency collision melts the welding surface of the workpiece, thereby achieving shaping. The shaping described in this technical solution means that the welding surface of the workpiece to be welded is unqualified due to processing accuracy, deformation, burrs, etc., especially the defects such as the length of the welded part is too long and uneven. After the above-mentioned collision and extrusion, the welded part becomes flat and the length of the excessive part becomes shorter, so that the shape of the welded workpiece meets the welding requirements, and then welding is performed.

[0038] The welding method is laser welding, and the material of the welded parts is plastic with a certain degree of light transmittance, which can be used for a variety of products such as car lights. The use of the above-mentioned high-frequency collision shaping can avoid the generation of dust, thereby preventing dust from remaining in the welded parts and affecting light transmittance and appearance. After shaping, the second welded part is placed on the first welded part, and the two are spliced ​​together along the welding surface. The translation mechanism 6 moves the shaping lifting seat 2 and the first and second welded parts thereon to the bottom of the welding clamping seat 5. The welding clamping seat 5 moves downward to clamp the first welded part and the second welded part, and then laser welding is used for welding.

[0039] In this embodiment, the shaping lifting seat 2 can be lifted and lowered by a plurality of methods such as screw drive, servo motor drive, etc., so as to adjust the height of the first welding part, so as to facilitate collision shaping. The welding pressing seat 5 can be driven up and down by a synchronous belt or the like. The structure of the translation mechanism 6 is as follows: Figure 5 shown.

[0040] like Figure 2 , Figure 3 , Figure 4As shown, the high-frequency collision shaping device 3 includes a driving seat 31 and a vibrating head 32. Both ends of the driving seat 31 are connected to the frame 1 through a vibration reduction device. After vibration reduction, the vibration of the driving seat 31 is very small. Three groups of excitation coils 33 arranged in the horizontal direction are arranged in the middle of the driving seat 31. Each group of the excitation coils 33 is provided with an armature 34 that can vibrate up and down. The three armatures 34 are connected to the vibrating head 32 as a whole. When the armature 34 vibrates up and down, the vibrating head 32 vibrates up and down accordingly. The excitation coil 33 is fixedly connected to the driving seat 31. Four spring vibration seats 321 are respectively arranged on both sides of the vibration head 32, and each of the spring vibration seats 321 is connected to a vibration spring 35, and the vibration spring 35 includes a fixed end 351 and a vibration end 352, and the fixed end 351 and the vibration end 352 both extend in the vertical direction and are arranged in parallel, and the fixed end 351 and the vibration end 352 are connected by a plurality of spring leaves 353, and the vibration end 352 of the vibration spring 35 is fixedly connected to the spring vibration seat 321, and the fixed end 351 of the vibration spring 35 is fixedly connected to the driving seat 31.

[0041] As 3, Figure 4 As shown, the structure of the vibration head 32 is arranged symmetrically, and the three groups of excitation coils 33 jointly apply a balanced driving force to the vibration mechanism 32. Under the action of the vibration springs 35 arranged in the same direction, the driving seat 31 applies a balanced resistance to the vibration head 32. The high-frequency collision shaping device 3 is relatively balanced as a whole, and can achieve high-frequency vibration with stable frequency, and its amplitude is affected by the current of the excitation coil 33.

[0042] In the linear vibration friction welding machine of the prior art, it drives the two workpieces to move relative to each other in the horizontal direction for friction, so its excitation coil drives the armature to swing in the horizontal direction. As for the technical solution of the present application, the excitation coil of the present application drives the armature to swing in the vertical direction. The difference between the two is not only that the present application realizes a new weld shaping method, namely high-frequency collision extrusion shaping, but also when the excitation coil is used to drive the armature to vibrate in the vertical direction, it is also necessary to use the technical solution of the present application to enable the second workpiece to collide with the first workpiece vertically at high frequency, rather than a swinging collision, or unable to form a stable high-frequency vibration, which is particularly important for the implementation of this solution. In addition, compared with linear vibration friction welding, the first workpiece and the second workpiece only need to move relative to each other to melt the surface, and the amplitude and stability of the vibration have little effect on the welding. However, for the collision extrusion of the present application, the amplitude and stability of the vibration will affect the shape of the weld after shaping, and then affect the depth and angle of the welding. This is a technical problem that does not exist in linear vibration friction welding and cannot be solved.

[0043] Furthermore, in order to better maintain the vibration stability of the vibration spring 35, the vibration spring 35 is located on the same side of the corresponding spring vibration seat 321, and the fixed end 351 of the vibration spring 35 is connected to the driving seat 31 through a spring fixing seat 36. The spring fixing seat 36 located on the same side of the driving seat 31 is fixedly connected through a stabilizing block 37, so that the spring fixing seat 36 remains consistent and the vibration spring 35 can vibrate synchronously.

[0044] Furthermore, a fixture installation hole is provided on one side of the vibration head 32 close to the shaping lifting seat 2 , and reinforcing ribs 322 are provided between two sides of the vibration head 32 .

[0045] Embodiment 2.

[0046] A laser welding method of the present embodiment uses a laser emitter 4 with a high-speed galvanometer for laser welding. During welding, the laser formed by the laser passes through the high-speed galvanometer to form a light spot at the weld between the first welding part and the second welding part. The laser is a high-power laser, and a section of the weld along its extension direction is the welding area. The light spot scans point by point in the welding area at a high frequency and cycles through multiple scans, so that the temperature of each point in the welding area gradually increases to melting.

[0047] Specifically, the product welded in this embodiment is a car lamp made of plastic. The first welded part is a light-absorbing bottom cover at the bottom, and the second welded part is a light-transmitting cover at the top. The weld is a spatial curve around the edge of the light-transmitting cover. Figure 6 The figure shows a welding area. The laser first forms a spot at the midpoint, which is marked as P. 1 , and then P 2 , P 3 , P 4 , P 5 , P 6 , P 7 , P 8 , P 9 , then return to P 10 , P 10 Can be used with P 8 overlap, and then P 11 , P 12 , P 13 , P 14 , P 15 , P 16 , P 17 , P 18 , P 19 , P 20 , P 21 , P 22 , P 23 , P 24 , P 25, P 26 , P 27 , P 28 , P 29 , P 30 , P 31 , P 32 , so far one scan is completed, and this cycle is repeated several times to achieve multiple scans in a cycle. In this process, the laser is used to simultaneously form a pulsed laser irradiation on multiple points in the welding area through a high-speed galvanometer, so that a high-power laser can be used to irradiate at a lower frequency, and the overall welding speed is fast due to the simultaneous welding of multiple points. In this way, the temperature welding time at a single point is long, the temperature rises slowly, and the heat at this point diffuses to the surrounding area, thereby reducing the temperature gradient and stress gradient, making the internal stress of the weld smaller and improving the welding quality.

[0048] Furthermore, in this embodiment, Figure 6 The adjacent points in the image may be seamless, partially overlapped, or have a certain spacing. The scanning method of each point can be as described above, starting from the midpoint and scanning left and right to complete a cycle, or starting from a point (starting point), scanning left or right to the end point and then returning to the starting point to complete a cycle.

[0049] In the above process, when the light spot scans once, each point is marked as Pi in turn, 0<i≤n, the number of times the light spot scans is m, and the light spot is at point P for the jth time. i The heat generated during the residence is Q ij , click P i The heat dissipated from the end of the j-1 scan to the end of the j scan is q ij The heat of the workpiece burning through is Q max , as long as it satisfies This ensures that the workpiece is not burned through, and the heat at each point gradually accumulates to melt the weldment.

[0050] The light spot is at point P for the jth time. i The dwell time is t ij , t ij ≥0, 10<m<20, the laser is a continuous laser or a pulsed laser, the power of the laser beam is 50-500W, the length of the welding area when the spot scans once is 5cm-20cm, and the time for the spot to complete a scan is 100ms-400ms. When t ij = 0, skip this point. This method can control the heating speed of different points, so as to better control the order of welding completion.

[0051] like Figure 7As shown, in this embodiment, the welding area is a plurality of non-overlapping areas. After the welding of one welding area S1 is completed, the position of the high-speed galvanometer is adjusted to weld in the next welding area S2. In this way, the welding process is block welding, that is, after the welding of all welding areas S1 is completed, the welding of the next welding area S2 is carried out.

[0052] As another embodiment, Figure 8 As shown, the welding area is a plurality of partially overlapping areas, and the welding area moves forward along the weld. The welding process is performed continuously along the weld, that is, the previous welding area S1 overlaps with the next welding area S2, and when the welding of the S1 part is completed, the welding of the next welding area S2 has already begun.

[0053] During welding, the focal position of the laser beam is 2-10mm below the welding surface, and the radius of the spot is 0.5mm-3mm.

[0054] Furthermore, the welding surface is shaped before welding. During the shaping, the first welding part is first fixed by the shaping lifting seat 2, and the high-frequency collision shaping device 3 drives the second welding part to collide and extrude the first welding part at a high frequency within a small distance along the vertical direction of the work table. The amplitude of the second welding part is 0.2-2mm, and the vibration frequency is 50-1000Hz. The heat generated by the collision causes the surface of the collision to melt and then deform, so that the shape of the workpiece welding surface meets the welding requirements, and then the laser emitter 4 is used for laser welding.

[0055] Furthermore, during high-frequency collision and extrusion, as the second welded part vibrates, the second welded part separates from the first welded part after impacting the first welded part, or the second welded part is in continuous contact with the first welded part, or before the weld surface melts, the second welded part separates from the first welded part after impacting the first welded part, and after the weld surface melts, the second welded part is in continuous contact with the first welded part. In the case where the second welded part is in continuous contact with the first welded part, the first welded part and the second welded part can be pre-welded in this manner, and then further welded by laser welding.

[0056] Furthermore, in this embodiment, the welding surfaces of the first welding part and the second welding part are provided with a plurality of welding points, and the welding points protrude from the welding surface. Pre-welding is performed after shaping. During pre-welding, the second welding part continues to collide and extrude the first welding part at a small distance with high frequency, and the second welding part continues to contact the first welding part. Under the action of high-frequency extrusion, the welding surface continues to be heated and melted, and then the high-frequency collision and extrusion are stopped, and the welding surface is cooled, so that part or all of the welding surface is in reliable contact, so that the heat of the laser can be transferred to the welding surface.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. Welding surface shaping laser welding machine, characterized by: The invention comprises a frame (1), wherein the frame (1) is provided with a shaping lifting seat (2) for fixing a first welding part, a high-frequency collision shaping device (3) for driving a second welding part to collide with the first welding part at a high frequency in a vertical direction to shape the welding surface of the workpiece, a laser emitter (4) with a high-speed galvanometer, and a liftable welding clamping seat (5), wherein the high-frequency collision shaping device (3) is located above the shaping lifting seat (2), the frame (1) is provided with a translation mechanism (6) for translating the shaping lifting seat (2) to below the welding clamping seat (5), and the laser emitter (4) is located above the welding clamping seat (5); The high-frequency collision shaping device (3) comprises a driving seat (31) and a vibrating head (32), the two ends of the driving seat (31) are connected to the frame (1), an excitation coil (33) is arranged in the middle of the driving seat (31), the excitation coil (33) is provided with an armature (34) that can vibrate up and down, the armature (34) is fixedly connected to the vibrating head (32), and a plurality of spring vibrating seats (321) are respectively arranged on both sides of the vibrating head (32), each of the spring vibrating seats (321) is connected to a vibrating spring. A vibration spring (35), the vibration spring (35) comprising a fixed end (351) and a vibration end (352), the fixed end (351) and the vibration end (352) both extending in a vertical direction and arranged in parallel, the fixed end (351) and the vibration end (352) being connected via a plurality of spring leaves (353), the vibration end (352) of the vibration spring (35) being fixedly connected to the spring vibration seat (321), and the fixed end (351) of the vibration spring (35) being fixedly connected to the driving seat (31).

2. The welding surface shaping laser welding machine according to claim 1, characterized in that: A plurality of groups of excitation coils (33) arranged in a horizontal direction are provided in the middle of the driving seat (31), each group of the excitation coils (33) is provided with an armature (34) that can vibrate up and down, and the vibration spring (35) is located on the same side of the corresponding spring vibration seat (321).

3. The welding surface shaping laser welding machine according to claim 2, characterized in that: The excitation coils (33) are in three groups, and four spring vibration seats (321) are respectively arranged on both sides of the vibration head (32).

4. The welding surface shaping laser welding machine according to claim 1, characterized in that: The fixed end (351) of the vibration spring (35) is connected to the driving seat (31) via a spring fixing seat (36), and the spring fixing seat (36) located on the same side of the driving seat (31) is fixedly connected via a stabilizing block (37).

5. A laser welding method, characterized in that: Laser welding is performed using the laser emitter (4) with a high-speed galvanometer as described in claim 1. During welding, the laser light formed by the laser passes through the high-speed galvanometer to form a light spot at the weld between the first welding part and the second welding part. The laser is a high-power laser, and a section of the weld along its extension direction is the welding area. The light spot scans point by point in the welding area at a high frequency and cycles through multiple scans, so that the temperature of each point in the welding area gradually increases to melting.

6. The laser welding method according to claim 5, characterized in that: Before welding, the welding surface is shaped. During the shaping process, the second welding piece is firstly subjected to high-frequency collision and extrusion against the first welding piece within a small distance. The amplitude of the second welding piece is 0.2-2 mm, and the vibration frequency is 50-1000 Hz. The heat generated by the collision causes the surface at the collision to melt and then deform, so that the shape of the workpiece welding surface meets the welding requirements. Then, the laser emitter (4) is used to perform laser welding.

7. The laser welding method according to claim 5, characterized in that: The first welding part and the second welding part are made of plastic. When the spot scans once, each point is marked as P in turn. i , 0<i≤n, the number of cycles of the light spot scanning is m, and the light spot is at point P for the jth time i The heat generated during the dwell time is Q ij , click P i The heat dissipated from the end of the j-1 scan to the end of the j scan is q ij The heat of workpiece burning through is Q max , 8. The laser welding method according to claim 7, characterized in that: The light spot is at point P for the jth time. i The dwell time is t ij , t ij ≥0, 10<m<20, the laser is a continuous laser or a pulsed laser, the power of the laser beam is 50-500W, the length of the welding area when the spot scans once in a cycle is 5cm-20cm, and the time for the spot to complete a scan is 100ms-400ms.

9. The laser welding method according to claim 7, characterized in that: During welding, the focal position of the laser beam is 2-10 mm below the welding surface, and the radius of the spot is 0.5-3 mm.

10. The laser welding method according to claim 6, characterized in that: The welding surfaces of the first welding part and the second welding part are provided with a plurality of welding points, and the welding points protrude from the welding surfaces. Pre-welding is performed after shaping. During pre-welding, the second welding part continues to collide and squeeze the first welding part at a high frequency within a small distance, and the second welding part continues to contact the first welding part until part or all of the welding surfaces are in reliable contact.

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