Laser welding lens structure and laser welding equipment

Abstract

The present invention discloses a laser welding lens structure and a laser welding device, and relates to the technical field of laser welding. The laser welding lens structure includes a first lens portion and a cylindrical lens portion. A lens portion is configured to receive a laser beam projected along a preset direction, and the first lens portion is used to converge or diverge the laser beam. The first lens portion and the cylindrical lens portion are sequentially arranged at intervals along the preset direction. The focal points of the cylindrical lens portion and the first lens portion do not overlap. The laser beam can sequentially project the first lens portion and the cylindrical lens portion along the preset direction to obtain a first laser focusing portion and a second laser focusing portion in the preset direction. There is a predetermined angle between the projections of the first laser focusing portion and the second laser focusing portion along the preset direction. The laser welding lens structure is applied to laser welding, and the welding quality is improved by the effect of the laser welding lens structure on the laser beam.

Description

Technical Field

[0001] The present invention relates to the technical field of laser welding, and in particular to a laser welding lens structure and laser welding equipment. Background Art

[0002] Laser welding technology belongs to fusion welding, which uses laser beam as energy to impact the weldment joint to achieve the welding purpose.

[0003] Laser welding is an efficient and precise welding method that uses a high-energy-density laser beam as a heat source. Laser welding is one of the important aspects of the application of laser material processing technology. In the 1970s, it was mainly used for welding thin-walled materials and low-speed welding. The welding process is a heat conduction type, that is, the laser radiation heats the surface of the workpiece, and the surface heat diffuses to the inside through heat conduction. By controlling the width, energy, peak power and repetition frequency of the laser pulse, the workpiece is melted to form a specific molten pool.

[0004] However, the welding effect of existing laser welding is not good. Summary of the invention

[0005] The first object of the present invention is to provide a laser welding lens structure, which is applied to laser welding and improves welding quality through the effect of the laser welding lens structure on the laser beam.

[0006] The second object of the present invention is to provide a laser welding device, which is provided with the above-mentioned laser welding lens structure. By providing the laser welding lens structure, the welding quality can be effectively improved.

[0007] The embodiment of the present invention is achieved as follows:

[0008] A laser welding lens structure, comprising:

[0009] A first lens portion, the first lens portion is configured to receive a laser beam projected along a preset direction, and the first lens portion is used to converge or diverge the laser beam;

[0010] The cylindrical lens portion, the first lens portion and the cylindrical lens portion are sequentially arranged at intervals along a preset direction;

[0011] The focal points of the cylindrical lens portion and the first lens portion do not overlap;

[0012] The laser beam can sequentially project the first lens portion and the cylindrical lens portion along a preset direction to obtain a first laser focusing portion and a second laser focusing portion in the preset direction;

[0013] There is a predetermined angle between the projections of the first laser focusing portion and the second laser focusing portion along a preset direction.

[0014] The inventors found that the existing technology focuses all the energy on a very small point. In actual seam welding production, under the same welding molten pool effect conditions, the molten pool area on the product seam determines the strength of the weld, so the repeatability accuracy of the overlap between the laser focus movement trajectory and the product seam is very high. Therefore, in actual production operations, the overlap accuracy of the laser focus movement trajectory and the product seam is very high, which increases the difficulty of welding and makes it difficult to ensure the welding quality.

[0015] The inventor has designed the above-mentioned laser welding lens structure, which is applied to laser welding, and improves the welding quality through the effect of the laser welding lens on the laser beam. The laser welding lens structure includes a first lens portion and a cylindrical lens portion. The first lens portion and the cylindrical lens portion are sequentially arranged at intervals along a preset direction, and the first lens portion and the cylindrical lens portion act together on the laser beam emitted along the preset direction. It should be noted that the focal points of the cylindrical lens portion and the first lens portion do not overlap. Specifically, the laser beam is first acted upon by the first lens portion, which causes the laser beam to converge or diverge, so that the laser beam has a focus through the first lens portion; then the converged or diverged laser beam is acted upon by the cylindrical lens portion, and another focus is generated under the optical characteristics of the cylindrical lens portion, and due to the focusing effect of the cylindrical lens portion itself, the laser beam processed by the first lens portion directly passes through the axial plane of the cylindrical lens portion, and converges at the focus of the first lens portion to form a second laser focusing portion, and the laser beam acted upon by the cylindrical lens portion converges at the focus of the cylindrical lens portion to form a first laser focusing portion, and due to the characteristics of the cylindrical lens portion, the first laser focusing portion and the second laser focusing portion are There is a predetermined angle between the projections of the laser focusing part along the preset direction, that is, the light between the first laser focusing part and the second laser focusing part is distorted. During welding, it is only necessary to place the product to be welded between the first laser focusing part and the second laser focusing part. The reason is that during welding, due to various reasons, such as the processing error of the product to be welded itself and the error of the technician debugging, when the distance between the product to be welded and the lens fluctuates, as long as the range of the fluctuation is between the first laser focusing part and the second laser focusing part, because the power density of the laser is increased between the first laser focusing part and the second laser focusing part, that is, the molten pool is increased, so the obtained molten pool depth can be guaranteed to be greater than the required value. At the same time, because the first laser focusing part and the second laser focusing part are linear under the action of the cylindrical lens, in the actual welding process, the first laser focusing part and the second laser focusing part are at an angle of 45 degrees to each other with the seam of the product to be welded, then the focus point has a larger margin for the overlap of the welded product seam with the lens movement trajectory compared with the prior art. Finally, the repeatability accuracy requirement of the overlap between the trajectory of the laser focus movement and the product seam is reduced. The welding difficulty is reduced and the welding quality is guaranteed.

[0016] In one embodiment of the present invention:

[0017] The first lens portion includes at least one lens sheet,

[0018] The cylindrical lens part includes at least one cylindrical lens sheet.

[0019] In one embodiment of the present invention:

[0020] A distance from a center of the first lens portion to a center of the cylindrical lens portion is smaller than a focal length of the first lens portion and a focal length of the cylindrical lens portion.

[0021] In one embodiment of the present invention:

[0022] The cylindrical lens portion has four planes parallel to a preset direction.

[0023] In one embodiment of the present invention:

[0024] The four planes form a regular quadrilateral.

[0025] In one embodiment of the present invention:

[0026] The first lens portion is a convex lens portion;

[0027] The cylindrical lens portion protrudes along a preset direction away from the end surface of the convex lens.

[0028] In one embodiment of the present invention:

[0029] The convex lens portion is a plano-convex lens portion, which has a flat surface and an arc-shaped surface along a preset direction, and the arc-shaped surface is close to the cylindrical lens.

[0030] In one embodiment of the present invention:

[0031] The first lens portion is a concave lens portion;

[0032] The end surface of the cylindrical lens portion away from the concave lens is recessed in a direction of the concave lens portion.

[0033] In one embodiment of the present invention:

[0034] The concave lens portion is a plano-concave lens portion, which has a flat surface and an arc-shaped surface along a preset direction, and the arc-shaped surface is close to the cylindrical lens.

[0035] A laser welding device having any one of the above-mentioned laser welding lens structures.

[0036] The technical solution of the present invention has at least the following beneficial effects:

[0037] A laser welding lens structure provided by the present invention is applied to laser welding, and improves welding quality through the effect of the laser welding lens structure on the laser beam.

[0038] The present invention provides a laser welding device, which is provided with the above-mentioned laser welding lens structure. By providing the laser welding lens structure, the welding quality can be effectively improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0040] Figure 1 This is a schematic diagram of the structure of the laser welding lens in Example 1 of the present invention;

[0041] Figure 2 is a schematic structural diagram of the first lens portion in Example 1 of the present invention;

[0042] Figure 3 Schematic diagram of the structure of the cylindrical lens portion in Example 1 of the present invention;

[0043] Figure 4 This is a schematic diagram of the imaging principle of the first laser focusing part and the second laser focusing part in Example 1 of the present invention;

[0044] Figure 5 This is a schematic structural diagram of another laser welding lens structure in Example 1 of the present invention.

[0045] Icons: 10-laser welding lens structure; 10a-equally divided point; 10b-equally divided point; 10c-equally divided point; 10d-equally divided point; 11-first lens portion; 12-cylindrical lens portion; 20-laser welding lens structure; 21-optical lens; 81-first laser focusing portion; 82-second laser focusing portion; 90-laser beam; 110-flat surface; 111-arc surface; 120-plane surface; 210-convex lens surface; 211-cylindrical mirror surface. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0047] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0049] In the description of the present invention, it should be noted that the terms "inside", "below", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0050] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0051] In the present invention, unless otherwise clearly specified and limited, a first feature being above or below a second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them. Moreover, a first feature being above, above, and above a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being below, below, and below a second feature includes the first feature being directly below and obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0052] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0053] Example 1

[0054] The present embodiment provides a laser welding lens structure 10, which is applied in laser welding. The laser welding lens structure 10 acts on the laser beam to improve the welding quality.

[0055] Please refer to Figure 1 , Figure 1 The specific structure of the laser welding lens structure 10 in the embodiment is shown.

[0056] The laser welding lens structure 10 includes a first lens portion 11 and a cylindrical lens portion 12 .

[0057] The laser welding lens structure 10 is applied in laser welding, and the laser beam 90 passes through the laser welding lens structure 10 to form a molten pool on the welding workpiece.

[0058] Specifically, the first lens portion 11 is configured to receive the laser beam 90 emitted along a preset direction, and the first lens portion 11 is configured to converge or diverge the laser beam 90. Figure 1 In the figure, for easy understanding, the laser beam 90 is shown and the preset direction is indicated.

[0059] The first lens portion 11 and the cylindrical lens portion 12 are sequentially arranged at intervals along a preset direction, that is, the laser beam 90 is incident on the first lens portion 11 and the cylindrical lens portion 12 sequentially.

[0060] The focal points of the cylindrical lens portion 12 and the first lens portion 11 do not overlap. Due to the optical properties of the cylindrical lens portion 12 itself, a portion of the laser beam 90 converged or diverged by the first lens portion 11 is directly projected and focused at the original focus without being affected by the focusing of the cylindrical lens portion 12, and the focus is defined as the second laser focus portion 82; the other portion is affected by the focusing of the cylindrical lens portion 12 and focused at another location, and the focus is defined as the first laser focus portion 81.

[0061] In summary, the laser beam 90 can sequentially project the first lens portion 11 and the cylindrical lens portion 12 in a preset direction to obtain the first laser focusing portion 81 and the second laser focusing portion 82 in the preset direction. In addition, there is a predetermined angle between the projections of the first laser focusing portion 81 and the second laser focusing portion 82 in the preset direction, that is, the focused light between the first laser focusing portion 81 and the second laser focusing portion 82 is distorted.

[0062] Specifically, in this embodiment, the first lens portion 11 includes a lens piece that can diverge or converge the light path. In other specific embodiments, the first lens portion 11 can also be composed of multiple lens pieces, for example, two, three, and four lens structures that can diverge or converge the light path.

[0063] In this embodiment, the first lens portion 11 includes a cylindrical lens piece, which can make the projections of the first laser focusing portion 81 and the second laser focusing portion 82 along a preset direction have an angle, that is, a preset angle that can be artificially adjusted through the cylindrical lens piece structure. In other specific embodiments, the first lens portion 11 can also be composed of multiple cylindrical lens pieces, for example, two, three, four, etc.

[0064] It should be noted that, in the present embodiment, the distance from the center of the first lens portion 11 to the center of the cylindrical lens portion 12 is smaller than the focal length of the first lens portion 11 and the focal length of the cylindrical lens portion 12 .

[0065] Please refer to Figure 1 ,exist Figure 1 The specific structures of the first lens portion 11 and the cylindrical lens portion 12 in this embodiment can be seen in FIG.

[0066] The first lens portion 11 is a convex lens portion, and the first lens portion 11 converges the laser beam 90. Specifically, since the first lens portion 11 is summarized as a lens sheet in this embodiment, the convex lens portion is a convex lens, and the cylindrical lens portion 12 is an outward convex cylindrical lens, wherein the cylindrical lens portion 12 convexes along a preset direction away from the end surface of the convex lens.

[0067] Further, in this embodiment, please refer to Figure 2 and Figure 3 , Figure 2 4 shows the specific structure of the first lens unit 11 in this embodiment. Figure 3 The specific structure of the cylindrical lens section 12 in this embodiment is shown.

[0068] The convex lens portion, that is, the first lens portion 11 is a plano-convex lens portion, and the plano-convex lens portion, that is, a single plano-convex lens, has a flat surface 110 and an arcuate surface 111 along a preset direction, and the arcuate surface 111 is close to the cylindrical lens portion 12, and the centers of the flat surface 110 and the arcuate surface 111 are on the same straight line. It should be noted that in other specific embodiments, the lens type in the convex lens portion can also be a biconvex lens or a concave-convex lens. It should be noted that in other specific embodiments, since the first lens portion 11 can be composed of multiple convex lenses, the first lens portion 11 can also be composed of a plano-convex lens, a biconvex lens, and a concave-convex lens.

[0069] Please refer to Figure 3 In this embodiment, the cylindrical lens portion 12 is a cylindrical lens, and the cylindrical lens has four planes 120 parallel to a preset direction. The four planes 120 form a regular quadrilateral. It should be noted that in other specific embodiments, the structure of the cylindrical lens portion 12 may not be limited.

[0070] The significance of setting up a cylindrical lens is: please combine Figure 4 Come and see, Figure 4 FIG. 8 shows the imaging principle of the first laser focusing unit 81 and the second laser focusing unit 82:

[0071] The figure shows four equally divided points of the laser beam 90 on the cross section, namely, equally divided point 10a, equally divided point 10b, equally divided point 10c and equally divided point 10d. Among them, equally divided point 10a and equally divided point 10c are located in the axial plane of the cylindrical lens, and equally divided point 10b and equally divided point 10d are the radial planes of the cylindrical lens. Since the cylindrical lens converges the light in the axial direction to form a line on the axial plane of the cylindrical lens, that is, the propagation of light on the axial plane of the cylindrical lens is not affected by the focusing effect of the cylindrical lens. When the laser passes through the first lens portion 11, the equally divided points 10a and 10c are not affected by the focusing effect of the cylindrical lens, and the two endpoints of the first laser focusing portion 81 are formed on the first laser focusing portion 81, and then converge on the focus of the first lens portion 11, that is, the second laser focusing portion 82, and the equally divided points 10b and 10d are converged to form the first laser focusing portion 81, and the first laser focusing portion 81 is a linear focus, and the equally divided points 10a and 10c are not affected by the focusing effect of the cylindrical lens, and converge on the second laser focusing portion 82. After the equally divided points 10b and 10d converge on the first laser focusing portion 81, they are scattered according to the straight-line propagation of the light, and the two endpoints of the second laser focusing portion 82 are formed on the second laser focusing portion 82, and the first laser focusing portion 81 is also linear. Since the focusing principle of the cylindrical lens is to converge the light toward the axial plane, while the light on the axial plane is not affected, the preset angle between the projections of the first laser focusing portion 81 and the second laser focusing portion 82 in the preset direction is 90°, the first laser focusing portion 81 and the second laser focusing portion 82 are perpendicular to each other in space, and the optical path between the first laser focusing portion 81 and the second laser focusing portion 82 is twisted by 90°.

[0072] The inventors found that the existing technology focuses all the energy on a very small point. In actual seam welding production, under the same welding molten pool effect conditions, the molten pool area on the product seam determines the strength of the weld, so the repeatability accuracy of the overlap between the laser focus movement trajectory and the product seam is very high. Therefore, in actual production operations, the overlap accuracy of the laser focus movement trajectory and the product seam is very high, which increases the difficulty of welding and makes it difficult to ensure the welding quality.

[0073] The inventor has designed the above-mentioned laser welding lens structure 10, which is applied to laser welding. The laser welding lens structure 10 acts on the laser beam 90 to improve the welding quality. The laser welding lens structure 10 includes a first lens portion 11 and a cylindrical lens portion 12. The first lens portion 11 and the cylindrical lens portion 12 are sequentially arranged at intervals along a preset direction, and the first lens portion 11 and the cylindrical lens portion 12 act together on the laser beam 90 emitted along the preset direction. It should be noted that the focal points of the cylindrical lens portion 12 and the first lens portion 11 do not overlap. Specifically, the laser beam 90 is first acted upon by the first lens portion 11, and the first lens portion 11 makes the laser beam 90 converge or diverge, so that the laser beam 90 has a focus through the first lens portion 11; then, the converged or diverged laser beam 90 is acted upon by the cylindrical lens portion 12, and another focus is generated under the optical characteristics of the cylindrical lens portion 12, and due to the focusing effect of the cylindrical lens portion 12 itself, the laser beam 90 processed by the first lens portion 11 directly passes through the axial plane of the cylindrical lens portion 12, and at the focus of the first lens portion 11, The laser beam 90 under the action of the cylindrical lens part 12 converges to form the first laser focusing part 81 at the focus of the cylindrical lens part 12, and due to the characteristics of the cylindrical lens part 12, the projections of the first laser focusing part 81 and the second laser focusing part 82 along the preset direction have a predetermined angle, that is, the light between the first laser focusing part 81 and the second laser focusing part 82 is distorted. When welding, it is only necessary to place the product to be welded between the first laser focusing part 81 and the second laser focusing part 82. The reason is that when welding, due to various reasons, such as the processing error of the product to be welded itself and the error of the technicians' debugging, the distance between the product to be welded and the lens fluctuates, as long as the fluctuation range is between the first laser focusing part 81 and the second laser focusing part 82, because the power density of the laser increases between the first laser focusing part 81 and the second laser focusing part 82, that is, the molten pool increases, so the obtained molten pool depth can be guaranteed to be greater than the required value. At the same time, because the first laser focusing part 81 and the second laser focusing part 82 are focused in a linear shape under the action of the cylindrical lens, in the actual welding process, the first laser focusing part 81 and the second laser focusing part 82 are at a 45-degree angle to the joint of the product to be welded, which has a larger overlap margin between the joint of the welded product and the movement trajectory of the lens compared to the focus point of the prior art. Finally, the repeatability accuracy requirement of the overlap between the trajectory of the laser focus movement and the joint of the product is reduced, which reduces the difficulty of welding and ensures the welding quality.

[0074] It should be noted that this embodiment also provides another laser welding lens structure, in which the first lens portion 11 is a concave lens portion, and the end surface of the cylindrical lens portion 12 away from the concave lens portion is concave in the direction of the concave lens portion. The concave lens portion is a plano-concave lens portion, and the plano-concave lens portion has a flat surface and an arcuate surface along a preset direction, and the arcuate surface is close to the cylindrical lens portion.

[0075] It should be noted that a laser welding device is also provided in this embodiment. The laser welding device has the laser welding lens structure 10 provided above. By providing the laser welding lens structure 10, the welding quality of the laser welding device can be improved.

[0076] It should be noted that, in this embodiment, the first lens portion 11 and the cylindrical lens portion 12 are sequentially arranged at intervals along a preset direction, which can also be interpreted as:

[0077] The first lens portion 11 and the cylindrical lens portion 12 can be designed with optical structures between two opposite end faces of a lens: Figure 5 , Figure 5 The specific structure of another laser welding lens structure 20 provided in this embodiment is shown.

[0078] The main body of the laser welding lens structure 20 is an optical lens 21 , and two opposite end surfaces of the optical lens 21 along a preset direction are a convex lens surface 210 and a cylindrical mirror surface 211 .

[0079] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A laser welding lens structure, characterized in that: include: a first lens portion, wherein the first lens portion is configured to receive a laser beam emitted along a preset direction, and the first lens portion is configured to converge or diverge the laser beam; A cylindrical lens portion, wherein the first lens portion and the cylindrical lens portion are sequentially arranged at intervals along the preset direction; The focal points of the cylindrical lens portion and the first lens portion do not overlap; The laser beam can sequentially project the first lens portion and the cylindrical lens portion along the preset direction to obtain a first laser focusing portion and a second laser focusing portion in the preset direction; There is a predetermined angle between the projections of the first laser focusing portion and the second laser focusing portion along the preset direction, and the predetermined angle is 90°. During welding, the product to be welded is located between the first laser focusing portion and the second laser focusing portion, and the first laser focusing portion, the second laser focusing portion and the seam of the product to be welded are at an angle of 45 degrees to each other.

2. The laser welding lens structure according to claim 1, characterized in that: The first lens portion includes at least one lens sheet, The cylindrical lens part includes at least one cylindrical lens sheet.

3. The laser welding lens structure according to claim 1, characterized in that: A distance from a center of the first lens portion to a center of the cylindrical lens portion is smaller than a focal length of the first lens portion and a focal length of the cylindrical lens portion.

4. The laser welding lens structure according to claim 1, characterized in that: The cylindrical lens portion has four planes parallel to the preset direction.

5. The laser welding lens structure according to claim 4, characterized in that: The four planes form a regular quadrilateral.

6. The laser welding lens structure according to claim 1, characterized in that: The first lens portion is a convex lens portion; The end surface of the cylindrical lens portion away from the convex lens portion protrudes along the preset direction.

7. The laser welding lens structure according to claim 6, characterized in that: The convex lens portion is a plano-convex lens portion, and the plano-convex lens portion has a flat surface and an arc-shaped surface along a preset direction, and the arc-shaped surface is close to the cylindrical lens portion.

8. The laser welding lens structure according to claim 1, characterized in that: The first lens portion is a concave lens portion; An end surface of the cylindrical lens portion away from the concave lens portion is recessed in a direction of the concave lens portion.

9. The laser welding lens structure according to claim 8, characterized in that: The concave lens portion is a plano-concave lens portion, and the plano-concave lens portion has a flat surface and an arc-shaped surface along a preset direction, and the arc-shaped surface is close to the cylindrical lens portion.

10. A laser welding device, characterized in that: The laser welding equipment has the laser welding lens structure described in any one of claims 1-9.

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