CN219542023U

CN219542023U - Novel variable facula laser cutting head

Info

Publication number: CN219542023U
Application number: CN202223275597.XU
Authority: CN
Inventors: 高旭恒; 刘进辉; 丁建武
Original assignee: Guanghui Shanghai Laser Technology Co ltd
Current assignee: Guanghui Shanghai Laser Technology Co ltd
Priority date: 2022-12-07
Filing date: 2022-12-07
Publication date: 2023-08-18
Anticipated expiration: 2032-12-07

Abstract

The utility model discloses a novel variable-facula laser cutting head, which comprises an optical fiber output device, a collimating lens assembly, a afocal beam expanding variable-magnification lens assembly and a focusing lens assembly, wherein the optical fiber output device, the collimating lens assembly, the afocal beam expanding variable-magnification lens assembly and the focusing lens assembly are sequentially arranged along the direction of an optical path; the afocal beam expansion variable-magnification lens component comprises a front lens, a variable-magnification lens and a compensation lens which are arranged along the light path direction, wherein the position of the front lens is fixed, the variable-magnification lens and the compensation lens can reciprocate along the light path direction, and the beam expansion ratio of the afocal beam expansion variable-magnification lens component is changed by changing the position of the variable-magnification lens and/or the compensation lens. According to the utility model, the afocal beam expansion zoom lens component based on the Galilean negative-positive structure is added between the collimating lens component and the focusing lens component, so that the multiplying power of the optical system can be continuously changed according to requirements, the beam expansion ratio is continuously adjustable, and meanwhile, the focal position is kept unchanged, so that the size of a focal spot is changed, the size of the focal spot is continuously adjustable, and the cutting quality is improved.

Description

Novel variable facula laser cutting head

Technical Field

The utility model relates to the technical field of laser cutting equipment, in particular to a novel variable-facula laser cutting head.

Background

The laser cutting is a novel processing means which irradiates a material by utilizing focused high-power density laser to enable the material to be melted and gasified rapidly, and simultaneously blows out molten substances by means of high-speed airflow coaxial with a light beam, thereby realizing the cutting purpose. During laser cutting, the adjustment of the size of the light spot has a certain help to cut plates with different thicknesses.

The focal spot with small spot diameter and high energy density is generally adopted in the cutting of the sheet, the obtained kerf is narrow, the cutting efficiency is high, and the method plays an important role in high-speed cutting; when cutting thick plates, focal spots with large spot diameters are generally adopted, the obtained kerf is wide, molten metal materials can be blown away, large focal depth can be obtained, the verticality of a cutting section is good, and the cutting quality can be greatly improved. Therefore, in laser cutting, controlling the size and position of the laser focal spot is critical.

The internal optical path of the laser cutting head usually comprises two parts, namely a collimating mirror assembly for collimating the laser light emitted from the optical fiber and a focusing mirror assembly for focusing the parallel light, so that two common ways of changing the light spot are usually to change the position of the focusing mirror assembly or change the position of the collimating mirror assembly. In addition, a afocal zoom beam expanding system can be added between the existing collimating lens component and the focusing lens component and used for changing the magnification of the optical path of the cutting head.

While changing the position of the collimator lens assembly may change the magnification of the optical system, this focusing approach may result in a shift in the focal position. During zooming, about half of the focal point in the adjustable range is located inside the cutting head and cannot be truly focused on the workpiece surface. In addition, the focusing mode causes the focus to have an overlong stroke, and the risk of burning the nozzle exists under the condition that the position of the nozzle is fixed.

In addition, a zoom scheme has been proposed to incorporate an afocal zoom beam expansion system between the collimator lens assembly and the focusing lens assembly. In the zooming process, the focus is always positioned outside the nozzle of the cutting head, and the position of the focus is unchanged. However, the positive-negative-positive afocal zoom beam expanding system based on the kepler structure has the defects of long volume and small variable magnification range.

To this end, the present inventors have found a method for solving the above-mentioned problems through beneficial studies and studies, and the technical solutions to be described below are made in this context.

Disclosure of Invention

The technical problems to be solved by the utility model are as follows: aiming at the defects of the prior art, the novel variable-spot laser cutting head with small volume and large variable-magnification range is provided.

The technical problems to be solved by the utility model can be realized by adopting the following technical scheme:

a novel variable-facula laser cutting head comprises an optical fiber output device, a collimating mirror assembly, a afocal beam expanding zoom mirror assembly and a focusing mirror assembly which are sequentially arranged along the direction of an optical path; it is characterized in that the method comprises the steps of,

the afocal beam expansion variable-magnification lens component comprises a front lens, a variable-magnification lens and a compensation lens which are arranged along the light path direction, wherein the position of the front lens is fixed, the variable-magnification lens and the compensation lens can reciprocate along the light path direction, and the beam expansion ratio of the afocal beam expansion variable-magnification lens component is changed by changing the position of the variable-magnification lens and/or the compensation lens.

In a preferred embodiment of the present utility model, the front lens and the variable magnification lens are single-sided concave lenses, and the compensation lens is a double-sided convex lens.

In a preferred embodiment of the present utility model, the magnification of the afocal beam expanding variable magnification lens assembly is adjustable in a range of 2.0X to 6.0X.

In a preferred embodiment of the present utility model, the collimator lens assembly is a single-sided concave lens.

In a preferred embodiment of the present utility model, the focusing mirror assembly includes a lenticular lens and a meniscus lens arranged in the direction of the optical path.

Due to the adoption of the technical scheme, the utility model has the beneficial effects that:

1. according to the utility model, the afocal beam expansion zoom lens component based on the Galilean negative-positive structure is added between the collimating lens component and the focusing lens component, so that the multiplying power of an optical system can be continuously changed according to requirements, the beam expansion ratio is continuously adjustable, and meanwhile, the focal position is kept unchanged, so that the size of a focal spot is changed, the size of the focal spot is continuously adjustable, and the cutting quality is improved;

2. the focusing lens component adopts the aberration elimination design to compensate the aberration generated by the front group lens, is used for eliminating the aberration introduced by the focusing lens component and compensating the aberration generated by the front group lens, can greatly reduce wave front distortion and improve the beam quality of a focusing point;

3. the afocal beam expansion zoom lens component adopts a modularized design, and has the advantages of small volume, compact structure and strong practicability.

Drawings

In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the utility model, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural view of the present utility model.

Fig. 2 is a schematic structural view of the afocal beam expanding variable magnification lens assembly of the present utility model.

Detailed Description

The utility model is further described with reference to the following detailed drawings in order to make the technical means, the creation characteristics, the achievement of the purpose and the effect of the implementation of the utility model easy to understand.

Referring to fig. 1, a novel variable spot laser cutting head is shown, which comprises an optical fiber output device 100, a collimating mirror assembly 200, an afocal beam expanding variable magnification lens assembly 300 and a focusing mirror assembly 400, which are sequentially arranged along the direction of an optical path.

The optical fiber output device 100 is configured to diverge and output high-power laser output by an optical fiber, reduce optical power density of an output end surface, and avoid damage to the output end surface caused by the high-power laser.

The collimator lens assembly 200 is located behind the optical fiber output device 100 for collimating the divergent light beam output from the optical fiber output device 100 into a parallel light beam. In this embodiment, the collimator lens assembly 200 is a single-sided concave lens.

The afocal expanded beam variable magnification lens assembly 300 includes a front lens 310, a variable magnification lens 320, and a compensation lens 330 arranged along the optical path direction. The front lens 310 is fixed in position, the zoom lens 320 and the compensation lens 330 can reciprocate along the direction of the optical path, the beam expansion ratio of the afocal beam expansion zoom lens assembly 300 is changed by changing the positions of the zoom lens 320 and/or the compensation lens 330, the magnification adjustable range of the afocal beam expansion zoom lens assembly 300 is 2.0X-6.0X, the magnification of the optical system can be continuously changed according to the requirement, and meanwhile, the focal position is kept unchanged, so that the size of a focal spot is changed, the size of the focal spot is continuously adjustable, and the cutting quality is improved. In the present embodiment, the front lens 310 and the variable magnification lens 320 are single-sided concave lens compensation lenses 330 are double-sided convex lenses.

In addition, the variable magnification lens 320 and the compensation lens 330 are connected by a mechanical cam, which is designed according to a zoom curve and a compensation curve. In actual use, the mechanical cam is rotated to enable the zoom lens 320 to move along the zoom curve, and meanwhile the compensation lens 330 moves along the compensation curve, so that the focal length of the afocal beam-expanding zoom lens assembly 300 is changed, the multiplying power of the whole optical system is changed, and meanwhile, the output light beam is ensured to have good collimation characteristic all the time. The mechanical cam mechanism is a conventional device in the art and will not be described in detail herein. The afocal beam expanding variable magnification lens assembly 300 adopts a modularized structure, and has the advantages of small volume, compact structure and strong practicability.

The focusing lens assembly 400 is positioned behind the afocal beam-expanding variable magnification lens assembly 300, and serves to focus the parallel light beam emitted from the afocal beam-expanding variable magnification lens assembly 300 to a specific position. Specifically, the focusing lens assembly 400 includes a convex lens 410 and a meniscus lens 420 sequentially arranged in the direction of the optical path, which adopts an aberration-removing design for removing self-induced aberration and compensating aberration generated by the front group lens, can greatly reduce wavefront distortion, and improves the beam quality of the focused point.

The foregoing has shown and described the basic principles and main features of the present utility model and the advantages of the present utility model. It will be understood by those skilled in the art that the present utility model is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present utility model, and various changes and modifications may be made without departing from the spirit and scope of the utility model, which is defined in the appended claims. The scope of the utility model is defined by the appended claims and equivalents thereof.

Claims

1. A novel variable-facula laser cutting head comprises an optical fiber output device, a collimating mirror assembly, a afocal beam expanding zoom mirror assembly and a focusing mirror assembly which are sequentially arranged along the direction of an optical path; it is characterized in that the method comprises the steps of,

2. The novel variable spot laser cutting head of claim 1 wherein the front lens and the variable magnification lens are single sided concave lenses and the compensation lens is a double sided convex lens.

3. The novel variable spot laser cutting head of claim 1, wherein the magnification adjustable range of the afocal beam expanding variable magnification lens assembly is 2.0X-6.0X.

4. The novel variable spot laser cutting head of claim 1, wherein the collimator lens assembly is a single-sided concave lens.

5. The novel variable spot laser cutting head of claim 1 wherein the focusing mirror assembly comprises a biconvex lens and a meniscus lens disposed along the direction of the optical path.