Composite laser welding head

Abstract

The utility model relates to the field of laser welding equipment, and particularly discloses a composite laser welding head which comprises a multi-laser leading-in channel and a multi-laser composite structure, the multi-laser leading-in channel is used for leading in multi-wavelength laser, and the tail end of the laser leading-in channel is connected with the multi-laser composite structure. And the multi-laser composite structure is used for compositing the multi-wavelength laser guided in by the multi-laser guide-in channel. According to the laser welding device, required lasers can be compounded and then used for welding non-ferrous metals such as flat copper wires, so that only laser combinations with better welding effects such as infrared light and blue light can be selected, and splashing in the welding process is reduced.

Description

Technical Field

[0001] The utility model relates to the field of laser welding equipment, in particular to a composite laser welding head. Background Art

[0002] Flat copper wire is used in the stator winding of the flat wire motor. The flat copper wire is first made into a hairpin-like shape and inserted into the stator slot. The unbent ends are twisted, expanded, and cut flat to make them pair up, and finally welded to form a current loop.

[0003] The existing laser welding method for flat copper wire uses infrared laser for welding. Since copper has an extremely low absorption rate for infrared laser, laser welding requires a high-power laser, and the equipment cost is relatively high. High-power welding will cause a lot of heat input, which can easily damage the paint on the flat copper wire. At the same time, there will be a lot of spatter during the welding process, and the spatter can easily cause damage to the field lens protection sheet. Utility Model Content

[0004] The utility model aims to provide a composite laser welding head, which can reduce spatter during welding.

[0005] The purpose of the utility model can be achieved through the following technical solutions:

[0006] A composite laser welding head comprises a multi-laser introduction channel and a multi-laser composite structure, wherein the multi-laser introduction channel is used to introduce lasers of multiple wavelengths, the end of the laser introduction channel is connected to the multi-laser composite structure, and the multi-laser composite structure is used to composite the lasers of multiple wavelengths introduced by the multi-laser introduction channel.

[0007] In a further embodiment, the multiple wavelength lasers include infrared light and blue light.

[0008] In a further scheme, the multi-laser introduction channel includes an infrared light introduction connector, a red light collimator, a 30-degree red light reflector, a blue light introduction connector, a blue light collimator and a 30-degree blue light reflector. The infrared light introduction connector and the blue light introduction connector are arranged in parallel, the red light collimator and the blue light collimator are respectively connected below the infrared light introduction connector and the blue light introduction connector, the 30-degree red light reflector and the 30-degree blue light reflector are connected directly below the optical path exits of the red light collimator and the blue light collimator, and the upper and lower ends of the 30-degree red light reflector and the 30-degree blue light reflector are aligned and arranged in parallel, the infrared light reflected by the 30-degree red light reflector can be refracted through the 30-degree blue light reflector and then combined with the blue light reflected by the 30-degree blue light reflector to be input into the multi-laser composite structure.

[0009] In a further solution, the infrared light is emitted by an infrared laser emitter, and the blue light is emitted by a blue laser emitter.

[0010] In a further embodiment, the blue light reflector includes a mirror coated with a film that reflects only blue light, and the red light reflector includes a mirror coated with a film that reflects only red light.

[0011] In a further solution, the multi-laser composite structure includes a galvanometer and a field lens, the galvanometer is used to change the emission direction of the composite laser, the field lens is connected below the galvanometer optical path outlet, and the field lens is used to focus the composite light beam into a ring-shaped spot.

[0012] In a further embodiment, the galvanometer includes a first galvanometer reflector lens and a second galvanometer reflector lens, the first galvanometer reflector lens is arranged in the direction in which the composite laser is emitted from the laser introduction channel, the second galvanometer reflector lens is arranged in the direction in which the composite laser is reflected by the first galvanometer reflector lens, and the second galvanometer reflector lens is arranged above the field lens.

[0013] In a further embodiment, the field lens includes a focusing lens.

[0014] In a further embodiment, the multiple wavelength lasers include infrared light, green light and blue light.

[0015] In a further embodiment, the laser introduction channel includes an optical fiber.

[0016] Beneficial effects of the utility model:

[0017] This method uses a blue light and infrared laser composite welding method, which can reduce spatter during the welding process and obtain a more stable and higher quality welding effect.

[0018] The method can reduce the power of the infrared laser, reduce the heat input during the welding process, and reduce the risk of the insulating paint being burned near the welding area.

[0019] The method adopts a combination of a galvanometer and a field lens, and can quickly adjust the shape and size of the welding track by adjusting the emission direction of the galvanometer.

[0020] This method uses two lasers and a set of laser output units, and the cost can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 This is a schematic diagram of a composite laser welding head in an embodiment of the utility model;

[0023] Figure 2 It is the laser welding molten pool in the embodiment of the utility model;

[0024] In the figure: 1. Import channel; 2. Composite structure; 3. Galvanometer; 4. Field lens; 5. Infrared light import connector; 6. Red light collimator; 7. 45-degree red light reflector; 8. Blue light import connector; 9. Blue light collimator; 10. 45-degree blue light reflector. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0026] like Figure 1 As shown, a composite laser welding head includes a multi-laser introduction channel 1 and a multi-laser composite structure 2. The multi-laser introduction channel 1 is used to introduce multiple wavelength lasers. The end of the laser introduction channel 1 is connected to the multi-laser composite structure 2. The multi-laser composite structure 2 is used to composite the multiple wavelength lasers introduced by the multi-laser introduction channel 1.

[0027] Its working principle is that by setting up a composite multi-laser composite structure 2, the required laser can be composited and used for welding non-ferrous metals such as flat copper wires, so that only laser combinations with better welding effects can be selected, such as infrared light and blue light. Copper has an absorption rate of only 5% for infrared laser (1030-1090nm) at room temperature, while its absorption rate for blue light (430-470nm) at room temperature is as high as more than 50%. Therefore, adding blue laser as one of the light sources in laser welding can improve the welding effect and make the welding process more controllable; blue light and infrared laser are composited together through the multi-laser composite structure 2, so that the two laser beams overlap in space.

[0028] According to the above working principle, some preferred embodiments or implementation structures are provided, such as Figure 1As shown, the multi-laser introduction channel 1 includes an infrared light introduction connector 5, a red light collimator 6, a 45-degree red light reflector 7, a blue light introduction connector 8, a blue light collimator 9 and a 45-degree blue light reflector 10. The infrared light introduction connector 5 and the blue light introduction connector 8 are arranged in parallel, the red light collimator 6 and the blue light collimator 9 are respectively connected below the infrared light introduction connector 5 and the blue light introduction connector 8, the 45-degree red light reflector 7 and the 45-degree blue light reflector 10 are connected directly below the light path exits of the red light collimator 6 and the blue light collimator 9, and the upper and lower ends of the 45-degree red light reflector 7 and the 45-degree blue light reflector 10 are aligned and arranged in parallel, the infrared light reflected by the 45-degree red light reflector 7 can be refracted through the 45-degree blue light reflector 10 and then combined with the blue light reflected by the 45-degree blue light reflector 10 to be input into the multi-laser composite structure 2.

[0029] The infrared light is emitted by an infrared laser emitter, and the blue light is emitted by a blue laser emitter. The emitter here can preferably be a semiconductor laser emitter.

[0030] The 45-degree blue light reflector 10 includes a coated mirror that reflects only blue light, and the 45-degree red light reflector 7 includes a coated mirror that reflects only red light.

[0031] The multi-laser composite structure 2 includes a galvanometer 3 and a field lens 4. The galvanometer 3 is used to change the emission direction of the composite laser. The field lens 4 is connected below the optical path outlet of the galvanometer 3 and is used to focus the composite light beam into an annular light spot.

[0032] The galvanometer 3 includes a first galvanometer reflector lens 12 and a second galvanometer reflector lens 11. The first galvanometer reflector lens 12 is arranged in the direction in which the composite laser is emitted from the laser introduction channel 1, and the second galvanometer reflector lens 11 is arranged in the direction in which the composite laser is reflected by the first galvanometer reflector lens 12, and the second galvanometer reflector lens 11 is arranged above the field lens 4.

[0033] The first galvanometer reflective lens 12 and the second galvanometer reflective lens 11 can be driven to deflect by two small motors, so as to change the trajectory of the emitted laser in real time, so as to facilitate welding of different shapes, such as: circle, rectangle and straight line segment, etc.; at the same time, the galvanometer 3 can also more conveniently change the welding position.

[0034] The field lens 4 includes a focusing lens, such as a concave lens or a Fresnel lens.

[0035] In specific implementation, before welding, the insulating paint PI+PAI or PEEK composite material on the surface of the end of the flat copper wire needs to be removed by mechanical or laser paint removal, and the two flat copper wires to be welded are aligned, clamped and cut using a special flat wire welding fixture. The matching gap needs to be less than 0.3mm, and the left and right misalignment needs to be less than 0.3mm to ensure that the laser will not burn the paint during welding and to ensure a good solder joint appearance.

[0036] The servo axis moves the flat copper wire to the working position, and then the laser emitting unit moves to just above the flat wire. At this time, the laser focused spot is swung by the galvanometer 3 to be exactly located at the center of the cross section after the two flat copper wires are bonded.

[0037] A blue laser with a wavelength of 430-470nm and a power of ≥1000W and an infrared fiber laser with a wavelength of 1030-1090nm and a power of ≥1500W can be used to emit the blue laser and infrared laser that need to be composited.

[0038] Those skilled in the art should be able to conceive that the position of the flat wire to be welded should be photographed by a visual system, and the welding coordinates should be captured and analyzed to guide the laser welding.

[0039] The infrared laser and the blue laser respectively pass through the infrared light introduction connector 5 and the blue light introduction connector 8 to form an annular light spot, and then are reflected by the galvanometer 3 into the field lens 4, and finally focused on a point. The infrared laser passes through the infrared light introduction connector 5 or directly enters the red light collimator 6 through the optical fiber, is refracted by the red light collimator 6 and reaches the 45-degree red light reflector 7. The infrared laser is reflected by the 45-degree red light reflector 7 to the 45-degree blue light reflector 10.

[0040] The blue light enters the blue light collimator 9 through the blue light introduction connector 8, and is refracted by the blue light collimator 9 to reach the 45-degree blue light reflector 10. At this time, the infrared laser is refracted by the 45-degree blue light reflector 10 and the blue light is reflected by the 45-degree blue light reflector 10 to form a ring-shaped light beam, which enters the galvanometer 3 together; after the blue light and the infrared laser are combined into a laser beam, they are reflected by the first galvanometer reflector lens 12 and the second galvanometer reflector lens 11 in the galvanometer 3 and reach the field lens 4. Finally, the field lens 4 focuses the light beam into a ring-shaped light spot. The focused infrared laser and blue light are simultaneously irradiated on the two flat On the welding surface of the copper wire, the blue light reacts with the copper wire, and the two composite laser beams enter the galvanometer 3. Under the action of the motor-driven deflection of the first galvanometer reflector lens 12 and the second galvanometer reflector lens 11, the laser moves out of the set welding trajectory to weld the ends of the flat wire. The field lens 4 in the galvanometer 3 system focuses the parallel light beam reflected by the galvanometer 3 into a light spot with a very small diameter at the bottom; and the field lens 4 has a large processing range. Combined with the galvanometer 3, multiple required welding areas can be welded in sequence without changing the positions of the entire field lens 4 and the galvanometer 3 at the entire welding head.

[0041] Since blue light generally has a lower energy density, it performs moderate heat conduction welding, heating and melting the surface metal, creating an extremely stable molten pool, such as Figure 2As shown in the figure, there is very little spatter when the blue light and infrared laser are irradiated. At this time, the copper absorbs the infrared laser and quickly forms a welding keyhole. Since the energy density of the infrared laser is higher and the core diameter of the infrared laser is smaller, the penetration is stronger and the molten pool reaches a deeper level in a short time. Due to the presence of blue light, the welding keyhole will also be larger and the molten pool will be more stable, making it easier for the metal vapor generated in the keyhole to escape outward, minimizing the kinetic energy of the escaped steam, and effectively suppressing the generation of spatter. Finally, the light is stopped, the molten pool cools to form a welding point, and the welding of the flat copper wire is completed. In this process, due to the presence of blue light, the cooling speed of the molten pool is slower than that of the single infrared laser, which can make the metal vapor escape more calmly, the temperature gradient during and after welding is smaller, and welding defects such as pores and cracks are less likely to occur, so the final welding quality can be better guaranteed.

[0042] In this process, the blue light plays the role of preheating and slow cooling, and performs moderate heat conduction welding, and the infrared laser performs deep melting welding to obtain a deeper welding depth. The galvanometer 3 swings at a certain speed during the welding process, so that the blue light and infrared laser follow the required welding trajectory, and finally completes the welding process.

[0043] Those skilled in the art should be able to imagine that the multiple wavelength lasers can also be infrared light or other wavelength lasers instead of blue light, such as multiple wavelength lasers including infrared light, green light and blue light. The laser introduction channel 1 can be directly introduced through a channel formed by an optical fiber.

[0044] It should be noted that the terms "first", "second" etc. in the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged in appropriate circumstances, so that the embodiments of the present application described here. In the present application, the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inside", "outside", "middle", "vertical", "horizontal", "lateral", "longitudinal" etc. are based on the orientation or positional relationship shown in the accompanying drawings.

[0045] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0046] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments, and the above embodiments and descriptions are only for explaining the principle of the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, and these changes and improvements fall within the scope of the utility model to be protected.

Claims

1. A composite laser welding head, characterized in that: The invention comprises a multi-laser introduction channel (1) and a multi-laser composite structure (2), wherein the multi-laser introduction channel (1) is used to introduce lasers of multiple wavelengths, the end of the laser introduction channel (1) is connected to the multi-laser composite structure (2), and the multi-laser composite structure (2) is used to composite the lasers of multiple wavelengths introduced by the multi-laser introduction channel (1).

2. A composite laser welding head according to claim 1, characterized in that: The multiple wavelength lasers include infrared light and blue light.

3. A composite laser welding head according to claim 2, characterized in that: The multi-laser introduction channel (1) comprises an infrared light introduction joint (5), a red light collimator (6), a 45-degree red light reflector (7), a blue light introduction joint (8), a blue light collimator (9) and a 45-degree blue light reflector (10), wherein the infrared light introduction joint (5) and the blue light introduction joint (8) are arranged in parallel, the red light collimator (6) and the blue light collimator (9) are respectively connected below the infrared light introduction joint (5) and the blue light introduction joint (8), and the 45-degree red light reflector (10) is connected to the infrared light introduction joint (5) and the blue light introduction joint (8). The mirror (7) and the 45-degree blue light reflector (10) are connected directly below the light path exits of the red light collimating mirror (6) and the blue light collimating mirror (9), and the upper and lower ends of the 45-degree red light reflector (7) and the 45-degree blue light reflector (10) are aligned and arranged in parallel, and the infrared light reflected by the 45-degree red light reflector (7) can be refracted by the 45-degree blue light reflector (10) and then combined with the blue light reflected by the 45-degree blue light reflector (10) and input into the multi-laser composite structure (2).

4. The composite laser welding head according to claim 2, characterized in that: The infrared light is emitted by an infrared laser emitter, and the blue light is emitted by a blue laser emitter.

5. The composite laser welding head according to claim 3, characterized in that: The 45-degree blue light reflector (10) comprises a mirror coated with a film that reflects only blue light, and the 45-degree red light reflector (7) is a mirror coated with a film that reflects only red light.

6. The composite laser welding head according to claim 1, characterized in that: The multi-laser composite structure (2) comprises a galvanometer (3) and a field lens (4); the galvanometer (3) is used to change the emission direction of the composite laser; the field lens (4) is connected below the optical path outlet of the galvanometer (3); and the field lens (4) is used to focus the composite light beam into an annular light spot.

7. The composite laser welding head according to claim 6, characterized in that: The galvanometer (3) comprises a first galvanometer reflective lens (12) and a second galvanometer reflective lens (11); the first galvanometer reflective lens (12) is arranged in the direction in which the composite laser is emitted from the laser introduction channel (1); the second galvanometer reflective lens (11) is arranged in the direction in which the composite laser is reflected by the first galvanometer reflective lens (12); and the second galvanometer reflective lens (11) is arranged above the field lens (4).

8. The composite laser welding head according to claim 6, characterized in that: The field lens (4) comprises a focusing lens.

9. The composite laser welding head according to claim 1, characterized in that: The multiple wavelength lasers include infrared light, green light and blue light.

10. The composite laser welding head according to claim 1, characterized in that: The laser introduction channel (1) comprises an optical fiber.

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