A focusing device and a focusing method of a laser fusion welding head

Abstract

This invention discloses a focusing device and method for a laser welding head, comprising: a support assembly; a limiting assembly connected to the support assembly for limiting the position of a test piece and causing the test piece to be inclined relative to a horizontal plane; a weld seam trajectory provided on the test piece; and a scale disposed on the limiting assembly, with the scale graduations on the scale parallel to the weld seam trajectory. This invention features a simple structural design, allowing for rapid on-site calibration of the actual focal length of the laser welding head and appropriate adjustments to bring its focal length close to or close to the factory theoretical value.

Description

Technical Field

[0001] This invention relates to the field of laser processing, specifically to a focusing device and method for a laser welding head. Background Technology

[0002] The laser focal length positioning mechanism is a device that effectively confirms the position of the laser focal length, enabling the laser welding head to achieve better welding results.

[0003] In existing technologies, the focal length of the laser welding head is mainly determined by the theoretical value when the equipment leaves the factory. However, in actual use, factors such as damage and repair, and impacts can cause vibrations in the structure of the laser welding head, causing the focal length to deviate from the theoretical value, thus affecting the quality of laser welding. Once such a situation occurs, the only solution is to have the equipment manufacturer recalibrate the focal length, which results in downtime and increased operating costs, as well as disruption to production schedules. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a focusing device and method for laser welding heads. Its structure is simple, and it can quickly calibrate the actual focal length of the laser welding head on-site and make appropriate adjustments to make its focal length close to or close to the theoretical value from the factory.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] On the one hand, a focusing device for a laser welding head is provided, comprising:

[0007] Support assembly;

[0008] A limiting component, connected to the support component, is used to limit the position of the test piece and to make the test piece inclined relative to the horizontal plane; the test piece is provided with a weld seam trajectory;

[0009] And a scale, which is set on the limiting component, and the scale setting direction on the scale is parallel to the weld trajectory;

[0010] The actual focal length of the laser welding head is obtained by calculating the actual focal length F1 = theoretical focal length F ± sinα * ΔL1, where α is the angle between the test piece 100 and the horizontal plane, and ΔL1 is the distance between the scale mark and the reference mark corresponding to the narrowest point of the welding trajectory generated when the laser welding head moves along the projection of the weld trajectory on the horizontal plane. The reference mark is the scale mark corresponding to the focal length of the laser welding head when it is the theoretical focal length F.

[0011] Preferably, the support assembly includes a first support and a second support, which are arranged in parallel relative to each other, and both the first support and the second support have inclined surfaces.

[0012] Preferably, both the first bracket and the second bracket have inclined surfaces, and the angle between the inclined surfaces and the horizontal plane is 10-80°.

[0013] Preferably, the projection of the weld seam trajectory on the horizontal plane is located between the first support and the second support, and is parallel to the first support and the second support.

[0014] Preferably, the limiting component includes: a first limiting member and a second limiting member, the first limiting member being connected to the first bracket and the second limiting member being connected to the second bracket; the first limiting member and the second limiting member respectively define the position of one side of the test piece.

[0015] Preferably, the scale is disposed on the first limiting member and / or the second limiting member.

[0016] Preferably, the scale has a 0 mark, with one side of the 0 mark being a positive mark and the other side being a negative mark.

[0017] On the other hand, a focusing method for a laser welding head implemented by the above-mentioned focusing device is also provided, which includes the following steps:

[0018] Move the laser welding head to the area above the test piece, and make the laser welding head perpendicular to the horizontal plane. Turn on the teaching guide beam and adjust the position of the laser welding head so that the guide beam spot falls on the weld trajectory and the position of the guide beam spot corresponds to the reference scale L0 on the scale.

[0019] The focal length of the laser welding head is adjusted to the theoretical value F of the focal length at the factory by adjusting the height of the laser welding head.

[0020] The first position and the second position are determined on the projection of the weld trajectory onto the horizontal plane;

[0021] Turn on the laser welding head to generate a laser beam, and then keep the height of the laser welding head constant so that the laser beam generated by the laser welding head moves in a straight line from the first position to the second position along the projection of the weld track on the horizontal plane, or moves in a straight line from the second position to the first position along the projection of the weld track on the horizontal plane, so as to form a welding track corresponding to the weld track on the test piece.

[0022] The actual focal length of the laser welding head is obtained according to F1=F±sinα*ΔL1, where ΔL1 is the distance between the scale L1 corresponding to the narrowest point of the welding trajectory and the reference scale L0, and α is the angle between the test piece 100 and the horizontal plane.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The focusing device in this invention has a simple structure, is easy to operate, and has low cost. It can quickly calibrate the actual focal length of the laser welding head on site and make appropriate adjustments to make the focal length close to or equal to the theoretical value from the factory, thus ensuring welding quality. There is no need to return the device to the factory for recalibration and adjustment, thereby significantly reducing equipment downtime and improving work efficiency. Attached Figure Description

[0025] Figure 1 This is an overall structural diagram of the focusing device of the laser welding head in this invention;

[0026] Figure 2 A side view of the focusing device in this invention when the focal length of the laser welding head is the theoretical value of the focal length;

[0027] Figure 3 A side view of the focusing device in this invention during the process of the laser welding head moving from the first position A to the second position B;

[0028] Figure 4a The top and side views of the focusing device in this invention are shown when the laser welding head moves from the first position A to the second position B, and the scale corresponding to the narrowest point of the welding trajectory is behind the reference scale.

[0029] Figure 4b The top and side views of the focusing device in this invention are shown when the laser welding head moves from the first position A to the second position B, and the scale corresponding to the narrowest point of the welding trajectory is in front of the reference scale.

[0030] Figure 4c The top and side views of the focusing device in this invention are shown when the laser welding head moves from the second position B to the first position A, and the scale corresponding to the narrowest point of the welding trajectory is behind the reference scale.

[0031] Figure 4d The top and side views of the focusing device in this invention are shown when the laser welding head moves from the second position B to the first position A, and the scale corresponding to the narrowest point of the welding trajectory is in front of the reference scale. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] Example 1:

[0034] like Figure 1As shown, the focusing device for the laser welding head in this embodiment includes:

[0035] Base 1;

[0036] A support assembly, which is connected to the base 1;

[0037] A limiting component, connected to the bracket assembly, is used to limit the position of the test piece 100 and to make the test piece 100 inclined relative to the horizontal plane. The angle between the test piece 100 and the horizontal plane is α, and α is preferably 30-60°, particularly preferably 45°. A weld seam trajectory 101 is provided on the test piece 100. In this embodiment, the test piece 100 can be made of metal or non-metal material.

[0038] And a scale 2, which is set on the limiting component, and the scale setting direction on the scale 2 is parallel to the weld trajectory 101. In this embodiment, the scale unit on the scale 2 is millimeters (mm) or centimeters (cm).

[0039] At work, such as Figure 2 As shown, the laser welding head 200 is moved to the area above the test piece 100 by a robot, and then the robot is adjusted so that the laser welding head 200 is perpendicular to the horizontal plane. The teaching guide beam (such as red light) is turned on, and the position of the laser welding head 200 is adjusted so that the guide beam spot falls on the weld trajectory 101, and its position corresponds to the reference scale L0 (such as 0mm) on the scale 2. At the same time, the height of the laser welding head 200 is adjusted so that the focal length of the laser welding head 200 is the theoretical focal length value F at the factory.

[0040] The first position A and the second position B are determined on the projection of the weld trajectory 101 onto the horizontal plane;

[0041] Turn on the laser welding head 200 to generate a laser beam, and then... Figure 3 As shown, keeping the height of the laser welding head 200 constant, the laser beam generated by the laser welding head 200 moves linearly from the first position A to the second position B along the projection of the weld trajectory 101 on the horizontal plane, or moves linearly from the second position B to the first position A along the projection of the weld trajectory 101 on the horizontal plane, so as to form a welding trajectory 102 corresponding to the weld trajectory 101 on the test piece 100 (e.g., ...). Figures 4a-4d (As shown).

[0042] Furthermore, since the laser beam generated by the laser welding head 200 has hyperbolic characteristics, the spot size is different at the positive and negative defocus positions. At this time, the scale L1 corresponding to the narrowest point B of the welding trajectory 102 corresponds to the actual focal length F1 of the laser welding head 200. Furthermore, the actual focal length F1 of the laser welding head 200 can be obtained based on the distance between scale L1 and the reference scale L0, and the angle α between the test piece 100 and the horizontal plane. Specifically:

[0043] like Figure 4a As shown, when the laser beam generated by the laser welding head 200 moves in a straight line from the first position A to the second position B along the projection of the weld trajectory 101 on the horizontal plane, and the scale L1 corresponding to the narrowest point B of the welding trajectory 102 is behind the reference scale L0, the actual focal length value F1 = the theoretical focal length value F - sinα * ΔL1.

[0044] like Figure 4b As shown, when the laser beam generated by the laser welding head 200 moves in a straight line from the first position A to the second position B along the projection of the weld trajectory 101 on the horizontal plane, and the scale L1 corresponding to the narrowest point B of the welding trajectory 102 is in front of the reference scale L0, the actual focal length value F1 = theoretical focal length value F + sinα*ΔL1.

[0045] like Figure 4c As shown, when the laser beam generated by the laser welding head 200 moves in a straight line from the second position B to the first position A along the projection of the weld trajectory 101 on the horizontal plane, and the scale L1 corresponding to the narrowest point B of the welding trajectory 102 is behind the reference scale L0, the actual focal length value F1 = theoretical focal length value F + sinα*ΔL1.

[0046] like Figure 4d As shown, when the laser beam generated by the laser welding head 200 moves in a straight line from the second position B to the first position A along the projection of the weld trajectory 101 on the horizontal plane, and the scale L1 corresponding to the narrowest point B of the welding trajectory 102 is in front of the reference scale L0, the actual focal length value F1 = the theoretical focal length value F - sinα * ΔL1.

[0047] Wherein, ΔL1 is the distance between the scale L1 corresponding to the narrowest point B of the welding trajectory 102 and the reference scale L0.

[0048] Therefore, the device in this embodiment can quickly calibrate the actual focal length of the laser welding head on-site and make appropriate adjustments to make its focal length close to or equal to the theoretical value from the factory, ensuring welding quality. There is no need to return to the factory for recalibration and adjustment of the focal length, thereby significantly reducing equipment downtime and improving work efficiency.

[0049] Example 2:

[0050] The only difference between this embodiment and embodiment 1 is that, as shown in Figure 4, the support assembly includes:

[0051] The first bracket 3 and the second bracket 4 are both connected to the base 1 by fasteners such as screws or bolts, and are arranged relatively parallel to each other. At the same time, the first bracket 3 and the second bracket 4 both have inclined surfaces, and the angle between the inclined surfaces and the horizontal plane is 10-80°, preferably 30-60°. Meanwhile, the projection of the weld trajectory 101 on the horizontal plane is located between the first bracket 3 and the second bracket 4, and is parallel to the first bracket 3 and the second bracket 4.

[0052] The limiting component includes:

[0053] The first limiting member 5 and the second limiting member 6 are respectively connected to the first bracket 3 by fasteners such as screws or bolts, and the second limiting member 6 is connected to the second bracket 4 by fasteners such as screws or bolts; the first limiting member 5 and the second limiting member 6 respectively limit the position of one side of the test piece 100.

[0054] Meanwhile, the scale 2 is disposed on the first limiting member 5 and / or the second limiting member 6.

[0055] Example 3:

[0056] The only difference between this embodiment and embodiment 1 or 2 is that, Figure 1 As shown, for ease of calculation and observation, the reference scale L0 on the scale 2 is 0 (e.g., 0mm), and one side of the reference scale L0 is a positive scale and the other side is a negative scale, so the value of ΔL1 can be read directly.

[0057] Example 4:

[0058] This embodiment provides a focusing method for a laser welding head implemented using the focusing device described in any one of embodiments 1-3, which includes the following steps:

[0059] The laser welding head 200 is moved to the area above the test piece 100 by the robot, and then the robot is adjusted so that the laser welding head 200 is perpendicular to the horizontal plane. The teaching guide beam (such as red light) is turned on, and the position of the laser welding head 200 is adjusted so that the guide beam spot falls on the weld trajectory 101, and the position of the guide beam spot corresponds to the reference scale L0 (such as 0mm) on the scale 2.

[0060] The height of the laser welding head 200 is adjusted so that the focal length of the laser welding head 200 is at the theoretical value F of the focal length at the factory.

[0061] The first position A and the second position B are determined on the projection of the weld trajectory 101 onto the horizontal plane;

[0062] Turn on the laser welding head 200 to generate a laser beam, and then keep the height of the laser welding head 200 unchanged so that the laser beam generated by the laser welding head 200 moves in a straight line from the first position A to the second position B along the projection of the weld track 101 on the horizontal plane, or moves in a straight line from the second position B to the first position A along the projection of the weld track 101 on the horizontal plane, so as to form a welding track 102 on the test piece 100 corresponding to the weld track 101.

[0063] The actual focal length of the laser welding head 200 is obtained according to F1 = F ± sinα * ΔL1, where ΔL1 is the distance between the scale L1 corresponding to the narrowest point B of the welding trajectory 102 and the reference scale L0. Specifically, the process of obtaining the actual focal length value F1 is the same as that in Example 1. Figures 4a-4d The descriptions are partially the same, so I will not repeat them here.

[0064] In summary, the present invention has a simple structural design, is easy to operate, and has low cost. It can quickly calibrate the actual focal length of the laser welding head on site and make appropriate adjustments to make the focal length close to or equal to the theoretical value of the factory, thus ensuring welding quality. There is no need to return to the factory for recalibration and adjustment of the focal length, thereby significantly reducing equipment downtime and improving work efficiency.

[0065] It should be noted that, in this document, terms such as "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0066] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method of focusing a laser welding head by means of a focusing device of the laser welding head, characterized in that, The focusing device of the laser welding head comprises: a support assembly; a limiting assembly connected to the support assembly for limiting the position of the test piece and allowing the test piece to be arranged in an inclined manner relative to the horizontal plane, and a weld seam track being arranged on the test piece; and a scale arranged on the limiting assembly, and the scale marks being arranged in a direction parallel to the weld seam track; The focusing method comprises the following steps: moving the laser welding head to a region above the test piece, and then allowing the laser welding head to be perpendicular to the horizontal plane, turning on the teaching guide light beam, and adjusting the position of the laser welding head so that the guide light beam spot falls on the weld seam track, and the position of the guide light beam spot corresponds to the reference scale mark on the scale; adjusting the height of the laser welding head so that the focal length of the laser welding head is at the theoretical focal length F of the laser welding head when leaving the factory; determining a first position and a second position on the projection of the weld seam track on the horizontal plane; turning on the laser welding head to generate a laser beam, and then keeping the height of the laser welding head unchanged, so that the laser beam generated by the laser welding head moves linearly along the projection of the weld seam track on the horizontal plane from the first position to the second position, or from the second position to the first position, to form a welding track corresponding to the weld seam track on the test piece; obtaining the actual focal length value of the laser welding head according to F1=F±sinα*ΔL1, wherein α is the included angle between the test piece and the horizontal plane, and ΔL1 is the distance between the scale mark corresponding to the narrowest part of the welding track and the reference scale mark when the laser welding head moves linearly along the projection of the weld seam track on the horizontal plane, and the reference scale mark corresponds to the focal length of the laser welding head being the theoretical focal length F.

2. The focus seeking method of claim 1, wherein, The support assembly comprises a first support and a second support arranged in parallel relative to each other, and the first support and the second support each have an inclined surface.

3. The focusing device of claim 2, wherein The first support and the second support each have an inclined surface, and the included angle between the inclined surface and the horizontal plane is 10-80°.

4. The method of claim 2, wherein, The projection of the weld seam track on the horizontal plane is located between the first support and the second support and is parallel to the first support and the second support.

5. The method of claim 2, wherein, The limiting assembly comprises a first limiting member and a second limiting member, the first limiting member is connected to the first support, and the second limiting member is connected to the second support; the first limiting member and the second limiting member respectively correspond to the position of one side of the test piece.

6. The method of focusing according to claim 5, wherein, The scale is arranged on the first limiting member and / or the second limiting member.

7. The method of focusing according to claim 6, wherein, The scale has a 0 scale mark, and one side of the 0 scale mark is a positive scale mark and the other side is a negative scale mark.

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