Multi-layer composite coating laser cleaning device and method based on multiple laser light sources

Abstract

This invention relates to the field of laser cleaning technology, specifically disclosing a laser cleaning device and method for multi-layer composite coatings based on multiple laser light sources. The device includes a gantry frame and a movable platform positioned below it. A visual imaging component and a laser light source selector are mounted on the gantry frame above the movable platform. Multiple light source input terminals on the laser light source selector are respectively connected to laser light sources of different wavelengths, and the output terminal of the laser light source selector is connected to a galvanometer. This invention enables flexible switching and precise alignment of multiple laser light sources, simplifies the equipment structure, reduces optical path adjustment time, improves cleaning efficiency, and lowers operational difficulty, meeting the cleaning needs of different materials and coatings. It also enables full monitoring of the cleaning process, ensuring the ideality and consistency of the cleaning effect and improving the stability of product quality. Finally, it achieves intelligent cleaning of multi-layer composite coatings.

Description

Technical Field

[0001] This invention relates to the field of laser cleaning technology, and in particular to a laser cleaning device and method for multilayer composite coatings based on multiple laser light sources. Background Technology

[0002] With the continuous development of industrial technology, various composite coatings are widely used in aerospace, shipbuilding, automotive and other fields. These coatings are usually composed of multiple layers of different materials and have multiple functions such as corrosion protection, heat insulation, and decoration. During use, these coatings need to be replaced or repaired regularly, thus placing higher demands on the cleaning technology of composite coatings.

[0003] Laser cleaning, as a novel, non-contact, efficient, and environmentally friendly cleaning method, has been widely used in the field of composite coating cleaning in recent years. Compared with traditional chemical and mechanical cleaning methods, laser cleaning has advantages such as high precision, no secondary pollution, and high degree of automation. As a new surface treatment method, laser cleaning technology has advantages such as precision, efficiency, and environmental friendliness, and has been widely used in aerospace, automotive, and shipbuilding industries. Compared with traditional chemical and mechanical cleaning methods, laser cleaning has advantages such as non-contact operation, no chemical release, and ease of automation integration.

[0004] However, in the cleaning of composite coatings, due to the different absorption rates of different coating materials to lasers of different light sources and wavelengths, it is difficult to clean multiple coatings simultaneously using a single wavelength laser. Traditional laser cleaning methods often require multiple laser sources and complex optical systems, resulting in complex equipment structures and requiring a significant amount of time to adjust the optical path and align the workpiece during actual use. Existing laser cleaning technologies still have some problems when dealing with multi-layer composite coatings. Most laser cleaning devices can only use a single wavelength or a limited number of wavelengths of laser source, making it impossible to effectively clean multi-layer composite coatings composed of different materials. Secondly, existing technologies lack the ability to precisely control the peeling of multi-layer composite coatings layer by layer, which can easily cause damage to the underlying coating or substrate. Existing technologies also lack the ability to flexibly switch and combine different wavelength laser sources, making it impossible to select the optimal cleaning parameters for different coating characteristics.

[0005] Therefore, there is an urgent need to develop a multi-laser source laser cleaning device that can simultaneously meet the cleaning needs of different coatings and improve cleaning efficiency. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies by proposing a laser cleaning device and method for multi-layer composite coatings based on multiple laser light sources.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A multi-layer composite coating laser cleaning device based on multiple laser light sources includes a gantry frame and a movable loading platform below it. A visual imaging component and a laser light source selector are installed on the gantry frame above the movable loading platform. Multiple light source input terminals on the laser light source selector are respectively connected to laser light sources of different wavelengths, and a galvanometer is connected to the output terminal of the laser light source selector. The cleaning device also includes a control system for controlling the laser source selector, laser source, vision imaging components, and galvanometer.

[0008] Optionally, the laser source includes a mid-infrared laser source, a near-infrared laser source, a green laser source, and a violet laser source, all of which are connected to the four light source input terminals on the laser source selector via optical fibers.

[0009] Optionally, the gantry frame includes a first gantry column and a second gantry column on both sides, and a fixed crossbeam between the tops of the first gantry column and the second gantry column.

[0010] Optionally, the visual imaging component includes a vertical visual camera, a low-angle visual camera, and a high-angle visual camera; The vertical vision camera is rigidly mounted on a fixed crossbeam and located directly above the movable platform. The lens axis makes a 90-degree angle with the ground and the lens faces the movable platform. A low-angle vision camera is mounted on the lower end of the first gantry column, with the lens axis at an angle of 20-40 degrees to the ground and the lens facing the movable cargo platform. A high-angle vision camera is mounted on the upper part of the second gantry column, with the lens axis at an angle of 50-70 degrees to the ground, and the lens facing the movable cargo platform.

[0011] Optionally, the laser source selector is mounted on a fixed crossbeam, and the galvanometer is coaxially mounted with the output end of the laser source selector.

[0012] Optionally, the laser source selector includes an output axis and four sets of incident axes, as well as a conical beam terminator, and also includes a central axis. The output axis and the four sets of incident axes are all perpendicular to the central axis and are in the same plane, and the conical beam terminator is located on the central axis.

[0013] Optionally, the emission axis includes an acousto-optic tunable filter, an emission focusing lens, an emission diverging lens, and an emission collimating lens arranged coaxially in sequence. The center of the acousto-optic tunable filter is located on the central axis, and the conical beam terminator is located behind the acousto-optic tunable filter.

[0014] Optionally, the four incident axes are incident axis one, incident axis two, incident axis three, and incident axis four, respectively. The incident axis includes an incident diverging lens, an incident collimating lens, and a reflecting mirror arranged coaxially in sequence. The second incident axis includes an incident diverging lens, an incident collimating lens, and a dichroic filter arranged coaxially in sequence. The third incident axis includes a third incident diverging lens, a third incident collimating lens, and a second dichroic filter arranged coaxially in sequence. The incident axis four includes an incident diverging lens four, an incident collimating lens four, and a dichroic filter three arranged coaxially in sequence.

[0015] Optionally, the reflector, dichroic filter one, dichroic filter two, dichroic filter three, and acousto-optic tunable filter are sequentially located on the central axis, and their centers are all coaxial with the central axis. The reflector, dichroic filter one, dichroic filter two, dichroic filter three, and acousto-optic tunable filter are all at a 45-degree angle to the central axis.

[0016] A laser cleaning method for multilayer composite coatings based on multiple laser light sources, the cleaning method being based on the aforementioned cleaning apparatus, and further comprising the following steps: Step 1: Assemble the cleaning device; Step 2: Place the workpiece to be cleaned on the movable platform and wait for cleaning. Step 3: Adjust the position and angle of the components in the laser source selector so that all optical path axes on the central axis coincide. Step four: Set the optimal laser wavelength, laser power, scanning speed, and spot overlap rate for cleaning different coatings, and then clean the workpiece to be cleaned.

[0017] Compared with the prior art, the beneficial effects of the present invention are: This invention achieves flexible switching and precise alignment of multiple laser light sources by employing a combination of an optical path switching mechanism and a galvanometer mechanism, which simplifies the equipment structure, reduces optical path adjustment time, improves cleaning efficiency, and reduces operational difficulty, thus meeting the cleaning needs of different materials and coatings. This invention uses a visual imaging component to detect coating characteristics in real time, enabling full monitoring of the cleaning process, ensuring the ideality and consistency of the cleaning effect, and improving the stability of product quality.

[0018] This invention employs a layer-by-layer cleaning method, automatically selecting a suitable laser light source of appropriate wavelength based on the properties of different coatings. This achieves intelligent cleaning of multi-layer composite coatings, avoiding the limitations caused by single-wavelength lasers and improving cleaning quality and precision. Attached Figure Description

[0019] Fig. 1 This is a schematic diagram of the overall structure of the present invention; Fig. 2 This is a schematic diagram of the internal optical path structure of the laser source selector of the present invention.

[0020] In the diagram: 1. Control system; 2. Mid-infrared laser source; 3. Near-infrared laser source; 4. Green laser source; 5. Violet laser source; 6. Laser source selector; 7a. Vertical vision camera; 7b. Low-angle vision camera; 7c. High-angle vision camera; 8a. First gantry column; 8b. Second gantry column; 9. Fixed crossbeam; 10. Movable loading platform; 11. Galvanometer; 12a. Incident diverging lens one; 12b. Incident diverging lens two; 12c. Incident diverging lens three; 12d. Incident diverging lens four; 13a. Incident collimating lens one; 13b. Incident collimating lens two; 13c. Incident collimating lens three; 13d. Incident collimating lens four; 14. Mirror; 15. Dichroic filter one; 16. Dichroic filter two; 17. Dichroic filter three; 18. Acousto-optic tunable filter; 19. Outgoing focusing lens; 20. Outgoing diverging lens; 21. Outgoing collimating lens; 22. Conical beam terminator. Detailed Implementation

[0021] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0022] Reference Figs. 1-2 A multi-layer composite coating laser cleaning device based on multiple laser light sources includes a gantry frame and a movable loading platform 10 below it. A visual imaging component and a laser light source selector 6 are installed on the gantry frame above the movable loading platform 10. Multiple light source input terminals on the laser light source selector 6 are respectively connected to laser light sources of different wavelengths. A galvanometer 11 is connected to the output terminal of the laser light source selector 6. The cleaning device also includes a control system 1 for controlling the laser light source selector 6, the laser light source, the vision imaging component, the movable platform 10, and the galvanometer 11. All components are connected to the control system 1, enabling intelligent control during operation and making subsequent operations more precise and efficient.

[0023] Specifically, the laser source includes a mid-infrared laser source 2, a near-infrared laser source 3, a green laser source 4, and a violet laser source 5, all of which are connected to the four light source input terminals on the laser source selector 6 via optical fibers. Different wavelengths of laser light sources can meet the needs of cleaning different coatings and can be freely switched and selected via the laser source selector 6.

[0024] Specifically, the gantry frame includes a first gantry column 8a and a second gantry column 8b on both sides, and a fixed crossbeam 9 between the tops of the first gantry column 8a and the second gantry column 8b. The gantry frame facilitates the connection and installation of the visual imaging component and the laser light source selector 6 above the movable loading platform 10.

[0025] Specifically, the visual imaging components include a vertical visual camera 7a, a low-angle visual camera 7b, and a high-angle visual camera 7c. The vertical vision camera 7a is rigidly mounted on the fixed crossbeam 9 and is located directly above the movable platform 10. The lens axis makes a 90-degree angle with the ground and the lens faces the movable platform 10. A low-angle vision camera 7b is mounted on the lower end of the first gantry column 8a, with the lens axis at an angle of 20-40 degrees to the ground and the lens facing the movable cargo platform 10. A high-angle vision camera 7c is mounted on the upper part of the second gantry column 8b, with the lens axis at an angle of 50-70 degrees to the ground and the lens facing the movable cargo platform 10.

[0026] Cameras at different angles and positions can capture images of the workpieces placed on the movable platform 10 from all angles, thereby improving the visual imaging effect of the workpieces and making the cleaning of the workpieces more comprehensive and efficient.

[0027] Specifically, the laser source selector 6 is mounted on the fixed crossbeam 9, and the galvanometer 11 is coaxially mounted with the output end of the laser source selector 6.

[0028] Specifically, the laser source selector 6 includes an output axis and four sets of incident axes, as well as a conical beam terminator 22. It also includes a central axis. The output axis and the four sets of incident axes are all perpendicular to the central axis and are in the same plane. The conical beam terminator 22 is located on the central axis.

[0029] Specifically, the emission axis includes an acousto-optic tunable filter 18, an emission focusing lens 19, an emission diverging lens 20, and an emission collimating lens 21 arranged coaxially in sequence. The center of the acousto-optic tunable filter 18 is located on the central axis. A conical beam terminator 22 is located behind the acousto-optic tunable filter 18. The conical beam terminator 22 is used to absorb unselected laser light transmitted by the acousto-optic tunable filter 18.

[0030] Specifically, the four incident axes are incident axis one, incident axis two, incident axis three, and incident axis four. The four incident axes correspond to four different light sources. The infrared laser generated by the mid-infrared laser source 2 is transmitted through optical fiber and enters the internal optical path of the laser source selector 6 along the fourth incident axis. The near-infrared laser generated by the near-infrared laser source 3 is transmitted through optical fiber and enters the internal optical path of the laser source selector 6 along the third incident axis. The green laser generated by the green light source 4 is transmitted through optical fiber and enters the internal optical path of the laser source selector 6 along the second incident axis. The violet laser generated by the violet laser source 5 is transmitted through optical fiber and enters the internal optical path of the laser source selector 6 along the first incident axis.

[0031] The incident axis includes an incident diverging lens 12a, an incident collimating lens 13a, and a reflecting mirror 14 arranged coaxially in sequence. The second incident axis includes an incident diverging lens 12b, an incident collimating lens 13b, and a dichroic filter 15 arranged coaxially in sequence. The incident axis three includes an incident diverging lens three 12c, an incident collimating lens three 13c, and a dichroic filter two 16 arranged coaxially in sequence. The incident axis four includes an incident diverging lens four 12d, an incident collimating lens four 13d, and a dichroic filter three 17 arranged coaxially in sequence.

[0032] Specifically, the reflector 14, dichroic filter 15, dichroic filter 2 16, dichroic filter 3 17, and acousto-optic tunable filter 18 are located sequentially on the central axis, and their centers are all coaxial with the central axis. The reflector 14, dichroic filter 15, dichroic filter 2 16, dichroic filter 3 17, and acousto-optic tunable filter 18 are all at a 45-degree angle to the central axis.

[0033] A laser cleaning method for multilayer composite coatings based on multiple laser light sources, the cleaning method being based on the aforementioned cleaning apparatus, and further comprising the following steps: Step 1: Assemble the cleaning device; Step 2: Place the workpiece to be cleaned on the movable platform 10 and wait for cleaning. Step 3: Adjust the position and angle of the components in the laser source selector 6 so that all optical path axes on the central axis coincide. Step four: Set the optimal laser parameters, such as laser wavelength, laser power, scanning speed, and spot overlap rate, for cleaning different coatings, and then clean the workpiece to be cleaned.

[0034] After the cleaning operation begins, the movable platform 10 moves along a preset trajectory. The movable platform 10 utilizes existing technology and will not be described in detail here. It is assisted by a vertical vision camera 7a, a low-angle vision camera 7b, and a high-angle vision camera 7c to collect visual information of the coating on the surface of the workpiece to be cleaned and upload it to the control system 1. The control system 1 uses a preset visual recognition algorithm combined with the collected multi-angle information to complete the recognition of the surface coating. The control system 1 selects the laser source and matches it with the process based on the surface coating information. It also controls the acousto-optic tunable filter 18 in the laser source selector 6 to change the wavelength and intensity of the diffracted light, so that the laser with the selected wavelength and rated value is emitted from the laser source selector 6 and enters the galvanometer 11. The galvanometer 11 works in conjunction with the movable platform 10 to move the workpiece over a long distance and select the cleaning area. The galvanometer 11 moves the laser beam path to complete the scanning and cleaning of the area to be cleaned. After the workpiece surface coating is cleaned, the movable platform 10 moves according to the preset trajectory. The three vision cameras in the vision imaging component combine visual recognition to detect the cleaning effect online. If there is residue, the residual area is cleaned again. If there is no residue, the second layer of coating is identified, and the laser source is matched and the laser parameters are set according to the coating properties. By readjusting the acousto-optic tunable filter 18 in the laser source selector 6, the light source selection is completed, and the second layer of coating is cleaned. The above process is repeated to achieve the peeling of the multi-layer composite coating layer by layer.

[0035] Four lasers are introduced, and combined with the laser source selector 6 and galvanometer 11 system, the rapid switching of different wavelength laser sources can be achieved. At the same time, by optimizing the optical path design, the precise alignment of different source optical paths can be achieved to meet the cleaning needs of different coatings.

[0036] By using multiple vision cameras at different angles to collect image information of the workpiece surface to be cleaned, and by combining the multi-angle image information with an intelligent coating recognition algorithm, the coating information system can be intelligently judged, making coating cleaning more intelligent.

[0037] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A multi-layer composite coating laser cleaning device based on multiple laser light sources, comprising a gantry frame and a movable loading platform (10) disposed below it, characterized in that, The gantry is equipped with a visual imaging component and a laser light source selector (6) above the movable loading platform (10). Multiple light source input terminals on the laser light source selector (6) are respectively connected to laser light sources of different wavelengths, and the output terminal of the laser light source selector (6) is connected to a galvanometer (11). The cleaning device also includes a control system (1) for controlling the laser source selector (6), the laser source, the vision imaging assembly and the galvanometer (11).

2. The laser cleaning device for multi-layer composite coatings based on multiple laser light sources according to claim 1, characterized in that, The laser source includes a mid-infrared laser source (2), a near-infrared laser source (3), a green laser source (4), and a violet laser source (5), all of which are connected to the four light source input terminals on the laser source selector (6) via optical fibers.

3. The laser cleaning device for multi-layer composite coatings based on multiple laser light sources according to claim 2, characterized in that, The gantry frame includes a first gantry column (8a) and a second gantry column (8b) on both sides, and a fixed crossbeam (9) between the tops of the first gantry column (8a) and the second gantry column (8b).

4. The laser cleaning device for multi-layer composite coatings based on multiple laser light sources according to claim 3, characterized in that, The visual imaging assembly includes a vertical visual camera (7a), a low-angle visual camera (7b), and a high-angle visual camera (7c). A vertical vision camera (7a) is rigidly mounted on a fixed crossbeam (9) and located directly above a movable platform (10). The lens axis is at a 90-degree angle to the ground and the lens is facing the movable platform (10). A low-angle vision camera (7b) is mounted on the lower end of the first gantry column (8a), with the lens axis at an angle of 20-40 degrees to the ground and the lens facing the movable cargo platform (10). A high-angle vision camera (7c) is mounted on the upper end of the second gantry column (8b), with the lens axis at an angle of 50-70 degrees to the ground and the lens facing the movable cargo platform (10).

5. The laser cleaning device for multi-layer composite coatings based on multiple laser light sources according to claim 4, characterized in that, The laser source selector (6) is mounted on the fixed crossbeam (9), and the galvanometer (11) is coaxially mounted with the output end of the laser source selector (6).

6. The laser cleaning device for multi-layer composite coatings based on multiple laser light sources according to claim 5, characterized in that, The laser source selector (6) includes an output axis and four sets of incident axes and a conical beam terminator (22), and also includes a central axis. The output axis and the four sets of incident axes are all perpendicular to the central axis and are in the same plane. The conical beam terminator (22) is located on the central axis.

7. The laser cleaning device for multi-layer composite coatings based on multiple laser light sources according to claim 6, characterized in that, The emission axis includes an acousto-optic tunable filter (18), an emission focusing lens (19), an emission diverging lens (20), and an emission collimating lens (21) arranged coaxially in sequence. The center of the acousto-optic tunable filter (18) is located on the central axis, and the conical beam terminator (22) is located behind the acousto-optic tunable filter (18).

8. The laser cleaning device for multi-layer composite coatings based on multiple laser light sources according to claim 7, characterized in that, The four incident axes are incident axis one, incident axis two, incident axis three, and incident axis four, respectively. The incident axis includes an incident diverging lens (12a), an incident collimating lens (13a), and a reflecting mirror (14) arranged coaxially in sequence. The second incident axis includes an incident diverging lens (12b), an incident collimating lens (13b), and a dichroic filter (15) arranged coaxially in sequence. The incident axis three includes an incident diverging lens three (12c), an incident collimating lens three (13c), and a dichroic filter two (16) arranged coaxially in sequence. The incident axis four includes an incident diverging lens four (12d), an incident collimating lens four (13d), and a dichroic filter three (17) arranged coaxially in sequence.

9. The laser cleaning device for multi-layer composite coatings based on multiple laser light sources according to claim 8, characterized in that, The reflector (14), dichroic filter one (15), dichroic filter two (16), dichroic filter three (17), and acousto-optic tunable filter (18) are located sequentially on the central axis, and their centers are all coaxial with the central axis. The reflector (14), dichroic filter one (15), dichroic filter two (16), dichroic filter three (17), and acousto-optic tunable filter (18) are all at a 45-degree angle to the central axis.

10. A laser cleaning method for multilayer composite coatings based on multiple laser light sources, characterized in that, The cleaning method is based on the cleaning apparatus of claim 9, and the cleaning method further includes the following steps: Step 1: Assemble the cleaning device; Step 2: Place the workpiece to be cleaned on the movable platform (10) and wait for cleaning; Step 3: Adjust the position and angle of the components in the laser source selector (6) so that all optical path axes on the central axis coincide. Step four: Set the optimal laser wavelength, laser power, scanning speed, and spot overlap rate for cleaning different coatings, and then clean the workpiece to be cleaned.

Images