A variable focal length device for laser cleaning

Abstract

The present invention relates to a variable focal length device for laser cleaning, which includes a first lens module, a second lens module and a third lens module. Among them, the second lens module includes a second housing with openings at the upper and lower ends and at least one lens unit. Each lens unit includes a lens, a mounting ring and an adjusting rod. The lens is mounted in the second housing through the mounting ring. An adjustment hole is provided on the second housing, and the adjusting rod passes through the adjustment hole to connect the mounting ring. The first lens module and the third lens module are respectively fixed to the upper and lower ends of the second housing, and the first lens module is also connected to the output end of the galvanometer in the laser cleaning equipment. Compared with the prior art, the present invention can directly replace the field lens used in the existing fixed laser cleaning equipment and directly install it at the output end of the galvanometer to achieve the change of focal length; the present invention can directly transform the existing equipment, is convenient to use, easy to promote, and has strong practicability.

Description

Technical Field

[0001] The present invention relates to the technical field of laser cleaning, and in particular to a variable focal length device for laser cleaning. Background Art

[0002] Existing fixed focal length laser cleaning equipment, such as Figure 1 shown, includes a laser, a galvanometer, and a field lens. The field lens is a field lens for laser marking and serves as an optical element for laser focusing. The beam output by the laser is deflected by the galvanometer and then focused by the field lens. At the focal point, the smallest size spot is achieved. The size of this spot is directly proportional to the focal length according to optical theory. Commercial field lens products are designed with fixed focal lengths to focus on improving optical quality to meet the requirements of laser marking. During laser cleaning, for difficult-to-clean surfaces, a small spot is required to enhance the laser energy density; for easy-to-clean surfaces, a large spot is needed to improve the cleaning efficiency and protect the substrate material. Therefore, fixed focal length laser cleaning equipment is difficult to meet this requirement.

[0003] To solve the above problems, Chinese Utility Model Patent No. CN 206470467 U discloses a variable focal length optical unit for laser cleaning and a laser cleaning device, which adds a zoom element between the laser and the galvanometer to change the optical path, so that the focal point of the field lens changes, thereby achieving the purpose of changing the size of the focused spot. Chinese Utility Model Patent No. CN 207463739 U discloses an automatic zoom laser cleaning head device, which also adds a zoom element (liquid zoom lens) between the laser and the galvanometer to change the optical path and thus change the size of the final focused spot. However, the above-mentioned laser cleaning equipment with a zoom structure has the following problems: Implementing the pipeline change by adding a zoom element will increase the length of the optical path, resulting in a larger device length and a more complex structure. Especially for handheld laser cleaning equipment, it will lead to a decline in operating performance and inconvenience in use. At the same time, adding a zoom element requires modifying the internal structure of the existing laser cleaning equipment, with a small scope of application. Summary of the Invention

[0004] The purpose of the present invention is to overcome the above-mentioned defects existing in the prior art and provide a variable focal length device for laser cleaning.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] A variable focal length device for laser cleaning, comprising a first lens module, a second lens module and a third lens module. Among them, the second lens module includes a second housing with openings at the upper and lower ends and at least one lens unit. Each lens unit includes a lens, a mounting ring and an adjusting rod. The lens is mounted in the second housing through the mounting ring. An adjustment hole is provided on the second housing, and the adjusting rod passes through the adjustment hole to connect the mounting ring. The first lens module and the third lens module are respectively fixed at the upper and lower ends of the second housing. The first lens module is also connected to the output end of the galvanometer in the laser cleaning device.

[0007] Further, if the number of lens units is greater than or equal to two, the second housing includes a housing body and a mounting frame. The mounting frame includes a plurality of mounting cavities arranged side by side. The upper and lower ends of the mounting cavity are open. The lens units are respectively mounted in the mounting cavities. The adjustment holes are provided on the side walls of each mounting cavity. A fixing slot is provided on the housing body. The mounting frame is inserted into the fixing slot so that one of the mounting cavities of the mounting frame is located in the center of the housing body.

[0008] Further, the second housing further includes a draw plate. The draw plate is mounted on the upper end face of the mounting cavity and has a length greater than that of the mounting frame.

[0009] Further, the adjustment hole is cross-shaped or straight-shaped.

[0010] Further, the first lens module includes a first housing with openings at the upper and lower ends and a first lens. The first lens is mounted in the first housing.

[0011] Further, the first housing and the second housing are connected by screw threads.

[0012] Further, the third lens module includes a third housing with openings at the upper and lower ends and a third lens. The third lens is mounted in the third housing.

[0013] Further, the third housing and the second housing are connected by screw threads.

[0014] Further, the lens in the first lens module is a concave lens, and the lenses in the third lens module are all convex lenses.

[0015] Further, the focal lengths of the lenses in each lens unit are all different.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. The variable focal length device of the present invention can directly replace the field lens used in the existing fixed laser cleaning equipment and be directly installed at the output end of the galvanometer to achieve the change of focal length. This structure can achieve zooming without changing the internal structure of the existing fixed focal length laser cleaning equipment, and directly utilize the installation position of the field lens for installation. The present invention can directly transform the existing equipment, is convenient to use, easy to promote, and has strong practicability.

[0018] 2. The present invention can not only achieve small-range adjustment of the lens of the lens unit through the mounting ring and the adjusting rod, but also replace the lenses with different focal lengths through the mounting frame to achieve large-range adjustment, with strong applicability and can adapt to laser cleaning processes with a wide range of requirements.

[0019] 3. The setting of the draw plate can improve the structural stability of the lens unit and enhance the convenience of use. Description of the Drawings

[0020] Figure 1 Schematic diagram of the structural principle of the existing fixed focal length laser cleaning equipment.

[0021] Figure 2 Schematic diagram of the structure of Embodiment 1.

[0022] Figure 3 Exploded view of Embodiment 1.

[0023] Figure 4 Schematic diagram of the principle of Embodiment 1.

[0024] Figure 5 Schematic diagram of the structural principle of the laser cleaning equipment applying Embodiment 1.

[0025] Figure 6 Schematic diagram of the structure of Embodiment 2.

[0026] Figure 7 Exploded view of Embodiment 2.

[0027] Figure 8 Schematic diagram of the principle of Embodiment 2.

[0028] Reference numerals: 1. First lens module, 11. First housing, 12. First lens, 2. Second lens module, 21. Second housing, 211. Adjusting hole, 21a. Housing body, 21a-1. Fixed slot, 21b. Mounting frame, 21b-1. Mounting cavity, 21c. Draw plate, 22. Lens, 23. Mounting ring, 24. Adjusting rod, 3. Third lens module, 31. Third housing, 32. Third lens. Detailed Embodiments

[0029] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented on the premise of the technical solution of the present invention, and the detailed implementation manners and specific operation processes are given, but the protection scope of the present invention is not limited to the following embodiments.

[0030] Embodiment 1

[0031] As Figure 2 and Figure 3 shown, this embodiment provides a variable focal length device for laser cleaning, which includes a first lens module 1, a second lens module 2, and a third lens module 3. The specific structure is as follows:

[0032] The second lens module 2 includes a second housing 21 with openings at both the upper and lower ends and a lens unit. The lens unit includes a lens 22, a mounting ring 23, and an adjusting rod 24. The lens 22 is installed in the second housing 21 through the mounting ring 23. An adjustment hole 211 is provided on the side wall of the second housing 21, and the adjusting rod 24 passes through the adjustment hole 211 to connect the mounting ring 23. The first lens module 1 and the third lens module 3 are respectively fixed to the upper and lower ends of the second housing 21. The shape of the adjustment hole 211 can be cross-shaped or linear, preferably cross-shaped. The outer ring of the mounting ring 23 is an arc surface and is fixed by the frictional force and supporting force generated between it and the inner wall of the second housing 21.

[0033] The first lens module 1 includes a first housing 11 with openings at both the upper and lower ends and a first lens 12. The first lens 12 is installed in the first housing 11. The upper end of the first housing 11 is connected to the output end of the galvanometer in the laser cleaning device. The connection method can adopt existing snap structures, threaded structures, nested structures, etc., preferably a snap structure. The lower end of the first housing 11 is screwed to the upper end of the second housing 21 through a threaded structure. In this embodiment, the first lens 12 is a concave lens.

[0034] The third lens 32 includes a third housing 31 with openings at both the upper and lower ends and a third lens 32. The third lens 32 is installed in the third housing 31. The upper end of the third housing 31 is screwed to the upper end of the second housing 21 through a threaded structure. In this embodiment, the third lens 32 is a convex lens.

[0035] The working principle of this embodiment is as Figure 4 and Figure 5 shown. When using the laser cleaning device, by adjusting the adjusting rod 24 up and down or left and right, the relative positions and distances between the lens 22 in the lens unit and the first lens 12 and the third lens 32 can be adjusted, and thus the overall focal length of the entire device can be continuously adjusted.

[0036] Embodiment 2

[0037] As Figure 6 and Figure 7This embodiment provides a variable focal length device for laser cleaning, which includes a first lens module 1, a second lens module 2, and a third lens module 3. The specific structure is as follows:

[0038] The second lens module 2 includes a second housing 21 with openings at the upper and lower ends and a plurality of lens units. In this embodiment, three lens units are adopted. Each lens unit includes a lens 22, a mounting ring 23, and an adjusting rod 24. The focal lengths of the lenses 22 in each lens unit are different. The second housing 21 includes a housing body 21a and a mounting frame 21b. The mounting frame 21b is composed of a plurality of mounting cavities 21b-1 arranged side by side. The upper and lower ends of each mounting cavity 21b-1 are open, and the three lens units are respectively mounted in the mounting cavities 21b-1. An adjustment hole (not shown in the figure of Embodiment 2) is provided on the side wall of the mounting cavity 21b-1, and the adjusting rod 24 passes through the adjustment hole to connect the mounting ring 23. The shape of the adjustment hole is the same as that in Embodiment 1 and can be a cross shape or a straight shape, preferably a cross shape. The outer ring of the mounting ring 23 is an arc surface and is fixed by the frictional force and supporting force generated between it and the inner wall of the mounting cavity 21b-1. A fixing slot 21a-1 is provided on the housing body 21a, and the mounting frame 21b is inserted into the fixing slot 21a-1 for fixation. A pull plate 21c is also mounted on the upper end surface of the mounting frame 21b. The length of the pull plate 21c is greater than the length of the mounting cavity 21b-1, which can not only improve the structural stability of the lens unit but also improve the convenience of use.

[0039] The first lens module 1 includes a first housing 11 with openings at the upper and lower ends and a first lens 12. The first lens 12 is mounted in the first housing 11. The upper end of the first housing 11 is connected to the output end of the galvanometer in the laser cleaning device. The connection method can adopt existing snap structures, threaded structures, nested structures, etc., preferably a snap structure. The lower end of the first housing 11 is spirally connected to the upper end of the second housing 21 through a threaded structure. In this embodiment, the first lens 12 is a concave lens.

[0040] The third lens 32 includes a third housing 31 with openings at the upper and lower ends and a third lens 32. The third lens 32 is mounted in the third housing 31. The upper end of the third housing 31 is spirally connected to the upper end of the second housing 21 through a threaded structure. In this embodiment, the third lens 32 is a convex lens.

[0041] The working principle of this embodiment is as Figure 8 shown. When using the laser cleaning device, first, the lens unit is replaced by a horizontal pulling method, and the focal length is adjusted within a large range by selecting different types of lenses 22. Then, similar to Embodiment 1, the focal length is adjusted within a small range through the adjusting rods of each mounting cavity.

[0042] The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and variations based on the concept of the present invention without creative work. Therefore, all technical solutions that can be obtained by those skilled in the art in this technical field based on the concept of the present invention through logical analysis, reasoning, or limited experiments on the basis of the prior art should fall within the protection scope determined by the claims.

Claims

1. A variable focal length device for laser cleaning, characterized in that, It includes a first lens module (1), a second lens module (2) and a third lens module (3). Among them, the second lens module (2) includes a second housing (21) with openings at the upper and lower ends and at least one lens unit. Each lens unit includes a lens (22), a mounting ring (23) and an adjusting rod (24). The lens (22) is mounted in the second housing (21) through the mounting ring (23). An adjustment hole (211) is provided on the second housing (21). The adjusting rod (24) passes through the adjustment hole (211) and is connected to the mounting ring (23). The first lens module (1) and the third lens module (3) are respectively fixed at the upper and lower ends of the second housing (21). The first lens module (1) is also connected to the output end of the galvanometer in the laser cleaning device; If the number of lens units is greater than or equal to two, the second housing (21) includes a housing body (21a) and a mounting frame (21b). The mounting frame (21b) includes a plurality of mounting cavities (21b-1) arranged side by side. The upper and lower ends of the mounting cavities (21b-1) are open. The lens units are respectively mounted in the mounting cavities (21b-1). The adjustment hole (211) is provided on the side wall of each mounting cavity (21b-1). A fixing slot (21a-1) is provided on the housing body (21a). The mounting frame (21b) is inserted into the fixing slot (21a-1) so that one of the mounting cavities (21b-1) of the mounting frame (21b) is located at the center of the housing body (21a); The first lens module (1) includes a first housing (11) with openings at the upper and lower ends and a first lens (12). The first lens (12) is mounted in the first housing (11).

2. The variable focal length device for laser cleaning according to claim 1, wherein The second housing (21) further includes a draw plate (21c). The draw plate (21c) is mounted on the upper end face of the mounting cavity (21b-1) and has a length greater than that of the mounting frame (21b).

3. The variable focal length device for laser cleaning according to claim 1, wherein, The adjustment hole (211) is cross-shaped or linear.

4. A variable focal length device for laser cleaning according to claim 1, wherein, The first housing (11) and the second housing (21) are connected by screw threads.

5. The variable focal length device for laser cleaning according to claim 1, characterized in that, The third lens module (3) includes a third housing (31) with openings at the upper and lower ends and a third lens (32). The third lens (32) is mounted in the third housing (31).

6. The variable focal length device for laser cleaning according to claim 5, characterized in that, The third housing (31) and the second housing (21) are connected by screw threads.

7. A variable focal length device for laser cleaning according to claim 1, characterized in that, The lens in the first lens module (1) is a concave lens, and the lens in the third lens module (3) is a convex lens.

8. A variable focal length device for laser cleaning according to claim 1, characterized in that, The focal lengths of the lenses (22) in each lens unit are all different.

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