阅读说明：本技术 多聚焦点透镜大功率水导激光水光耦合装置 (High-power water-conducting laser water optical coupling device with multi-focus lens ) 是由 赵玉刚 刘谦 王珂 郑志龙 赵国勇 张海云 李丽 张桂香 孟建兵 周海安 高跃武 于 2021-09-23 设计创作，主要内容包括：本发明公开了多聚焦点透镜大功率水导激光水光耦合装置,属于激光加工技术领域。其特征为：光学透镜为多聚焦点透镜,平行的圆柱形激光束经过多聚焦点透镜后进入水光耦合装置,在进入水射流喷嘴后,沿着水射流的轴心线形成多个聚焦点,激光光束聚焦到每个光斑后再发散,以全反射的形式沿水射流水柱传输、实现水光耦合。与传统的水导激光水光耦合装置相比,本发明由于将原来球面透镜变成了多聚焦点透镜,聚焦点由一个变成了多个,每一个聚焦点的能量密度获得了显著的降低,有效避免了聚焦点处气爆现象的发生,从而显著提高了激光的功率,进而提高了水导激光的加工效率。(The invention discloses a high-power water-guided laser water-optical coupling device with a multi-focus lens, and belongs to the technical field of laser processing. It is characterized in that: the optical lens is a multi-focus lens, parallel cylindrical laser beams enter the water optical coupling device after passing through the multi-focus lens, a plurality of focusing points are formed along the axial lead of the water jet after entering the water jet nozzle, the laser beams are focused to each light spot and then are dispersed, and the laser beams are transmitted along the water jet column in a total reflection mode to realize water optical coupling. Compared with the traditional water-guided laser water optical coupling device, the invention changes the original spherical lens into a multi-focus lens, so that one focus point is changed into a plurality of focus points, the energy density of each focus point is obviously reduced, the occurrence of gas explosion at the focus point is effectively avoided, the power of laser is obviously improved, and the processing efficiency of water-guided laser is improved.)

1. The high-power water-conduction laser water optical coupling device of the multi-focus lens is characterized in that: the device comprises a multi-focus lens (1), a water-light coupling cavity (2), a glass window (3), high-pressure purified water (4), a water jet nozzle (5), a focusing light column (6), a light-guiding water jet column (7), a cylindrical parallel laser beam (8) and the like; the optical lens adopts the multi-focus lens (1), the laser penetrates through the multi-focus lens (1) to form a plurality of laser focus points, the focus points are linearly distributed along the axial lead of the lens in the light guide water jet column (7), the laser energy is distributed in the focus points, compared with a spherical lens with only one focus point, the multi-focus lens (1) enables the energy density of each focus point to be remarkably reduced, thereby avoiding the generation of gas explosion of the light guide water jet column (7) and the occurrence of water-light coupling interruption phenomenon caused by the overlarge energy density of the focus point of the traditional single focus lens, enabling the power of the laser to be remarkably improved and the processing efficiency of the water guide laser processing system to be remarkably improved.

2. The water-light coupling device of the multi-focus lens high-power water-guided laser as claimed in claim 1, wherein: the focus focusing lens (1) is positioned right above the water-light coupling cavity (2); the water optical coupling cavity (2) is of a cylindrical structure, a cylindrical cavity is arranged inside the water optical coupling cavity, a circular hole (12) is formed in the center of the upper wall of the cavity and used for injecting a laser beam, and a piece of circular plate glass is fixed to the lower surface of the upper wall in a close fit mode to form a glass window (3) of the water optical coupling cavity;a water jet nozzle (5) is fixed at the center of the lower wall of the cavity; a water inlet hole (13) is formed in the cylindrical surface of the water optical coupling cavity, and high-pressure water enters from the water inlet hole and is sprayed out from the water jet nozzle (5) to form a cylindrical light-guide water jet water column (7); the curved surface of the multi-focus lens 1 is formed by intersecting a plurality of spherical surfaces with the same axial lead and different radiuses, and the radius R of the spherical surface at the top is₁The maximum is that the radius of the annular spherical surface which is farther away from the axis is smaller, and the radius Rn of the annular spherical surface which is farthest away from the axis, namely the most peripheral annular spherical surface is smallest; circular spherical radius R at lens edge position_nThe laser passes through the annular spherical surface to form a focusing point which is closest to the bottom surface of the lens; spherical surface at the top of the lens with radius R₁The laser penetrates through the spherical surface to form a focusing point which is farthest away from the bottom surface of the lens; the focusing points are uniformly distributed along the axial lead of the lens to form a plurality of focusing points; the laser passes through the corresponding focusing point, then is dispersed and emitted to the inner surface of the light guide water jet water column (7), and then is transmitted inside the light guide water jet water column (7) through total reflection; by the alignment adjustment of the multi-focus lens (1) and the water jet nozzle (5), the focus point (6) is positioned on the axis of the light guide water jet column (7), and the incident laser is ensured not to interfere with the upper surface of the water jet nozzle.

3. The water-light coupling device of the multi-focus lens high-power water-guided laser as claimed in claim 1, wherein: the multi-focus lens is characterized in that the projection areas of the coaxial top spherical surface and each annular spherical surface along the axial lead are equal, so that the laser energy density of each focus point (6) in the light-guide water jet water column (7) is equal; the total number of the top spherical surfaces and the annular spherical surfaces of the multi-focus lens is n, and the radius of a plane circle projected by the top spherical surfaces along the axial lead on a horizontal plane is r₁The excircle radius of the plane circular ring of the projection of the outermost annular spherical surface on the horizontal plane along the axis is r_nAt known r_nIn the case of (i) th (value range: 1 to n-1), the formula for calculating the excircle radius of the plane circle (i is 1) and the formula for calculating the excircle radius of the plane circle are

4. The water-light coupling device of the multi-focus lens high-power water-guided laser as claimed in claim 1, wherein: due to the use of the high-power water-guided laser water optical coupling device of the multi-focus lens in the water-guided laser processing system, the traditional water-guided laser processing system becomes a gas explosion-free water-guided laser processing system; the processing system consists of a laser (21), an optical fiber laser beam (22), a beam expanding collimating lens group (23), a spectroscope (24), a multi-focus lens (25), a water-light coupling cavity (26), a light guide water jet water column (27), a processed workpiece (28), a CCD camera (29), an attenuation sheet (30), an optical filter (31) and a total reflector (32); laser emitted by a laser (21) enters an optical fiber to form an optical fiber laser beam (22), then passes through a beam expanding collimating lens group (23) and a spectroscope (24) to reach a multi-focus lens (25), the laser beam passing through the multi-focus lens (25) enters a water optical coupling cavity (26) and then is focused into a plurality of focusing points from top to bottom along the inside of a light guide water jet column (27), the focusing points are emitted to the inner surface of the light guide water jet column (27) through divergence, and then transmitted to the surface of a workpiece to be processed (28) along the light guide water jet column (27) through total reflection, so that the workpiece to be processed (28) is processed; light reflected back from the water light coupling cavity (26) through the multi-focus lens (25) is reflected by the spectroscope (24) and the holophote (32), then passes through the optical filter (31) and the attenuation sheet (30) and reaches the CCD camera (29), the camera displays the alignment condition of a laser beam of laser which is emitted into the water light coupling cavity (26) through the multi-focus lens (25) and the light guide water jet column (27), and the relative position of the water jet nozzle and the multi-focus lens (25) in the water light coupling cavity (26) is adjusted through a mechanical transmission device, so that a focus point is positioned in the light guide water jet column (27), and the laser beam does not interfere with the upper surface of the water jet column (5).

Technical Field

The invention belongs to the technical field of laser processing, and particularly relates to a water optical coupling device of a water-guided laser processing system.

Background

Compared with the traditional laser cutting, the water-guided laser cutting has the following advantages:

(1) thermal damage can not be generated, because the sprayed water flow can cool the material in the laser pulse interval, the thermal deformation and the thermal damage of the material are greatly reduced, and the original structure and the original performance of the material are kept;

(2) the working distance of the water jet is large, and focusing is not needed;

(3) the sprayed water flow can take away the molten material in the cutting process, so that pollutants are reduced;

(4) the machining precision is high, and the method is particularly suitable for high-precision machining of thin-wall parts.

The water-guided laser can be used for cutting, punching, slotting, cleaning the surface of a workpiece and the like. Due to the characteristics of water-guided laser processing, the method has important popularization and application prospects in the processing fields of metal materials, semiconductors, glass, ceramics, carbon fiber composite materials and the like.

The traditional water optical coupling device inevitably generates an air explosion phenomenon when high-power laser is used, so that the water jet nozzle is damaged, the water optical coupling is interrupted, and the water-guided laser processing cannot be continuously carried out, so that the traditional water-guided laser processing system has low laser power and low processing efficiency, and the application and popularization of the water-guided laser processing technology are seriously restricted.

Disclosure of Invention

Aiming at the problem of gas explosion of water optical coupling of the traditional water-guided laser processing system, the inventor invents a multi-focus lens high-power water-guided laser water optical coupling device. The device changes one focusing point of the laser in the water jet into a plurality of focusing points, and the energy density of each focusing point is obviously reduced, so that the power of the laser can be obviously improved, and the processing efficiency of the water jet is improved. In order to achieve the purpose, the invention adopts the following technical scheme:

the high-power water-conduction laser water optical coupling device with the multi-focus lens is characterized in that the multi-focus lens (1) is adopted as an optical lens of the high-power water-conduction laser water optical coupling device, laser focusing points formed by the laser penetrating through the multi-focus lens (1) are linearly distributed in a light-conduction water jet water column (7) along the axial lead of the lens, so that the energy of the laser is distributed in a plurality of focusing points, the energy density of each focusing point is remarkably reduced, the phenomena of gas explosion generation and water optical coupling interruption of the light-conduction water jet water column (7) caused by the overlarge energy density of the focusing points of the traditional single focusing point lens are avoided, the power of the laser can be remarkably improved, and the processing efficiency of a water-conduction laser processing system is also remarkably improved.

The high-power water-guided laser water-optical coupling device with the multi-focus lens comprises the multi-focus lens (1), a water-optical coupling cavity (2), a glass window (3), high-pressure purified water (4), a water jet nozzle (5), a focusing light column (6), a light-guiding water jet water column (7), a cylindrical parallel laser beam (8) and the like, wherein the multi-focus lens (1) is positioned right above the water-optical coupling cavity (2).

The water optical coupling cavity (2) is of a cylindrical structure, a cylindrical cavity is arranged inside the water optical coupling cavity, a circular hole (12) is formed in the center of the upper wall of the cavity and used for injecting a laser beam, and a piece of circular plate glass is fixed to the lower surface of the upper wall in a close fit mode to form a glass window (3) of the water optical coupling cavity; a water jet nozzle (5) is fixed at the center of the lower wall of the cavity; and a water inlet (13) is arranged on the cylindrical surface of the water optical coupling cavity, and high-pressure water enters from the water inlet and is sprayed out from the water jet nozzle (5) to form a cylindrical light-guide water jet column (7).

The curved surface of the multi-focus lens (1) is formed by intersecting a plurality of spherical surfaces with the same axial lead and different radiuses, and the spherical surface at the top has the radius R₁At the maximum, the farther from the axis the annular spherical surface has the smaller radius, and the farthest from the axis, that is, the most peripheral annular spherical surface has the radius R_nMinimum; circular spherical radius R at lens edge position_nThe laser passes through the annular spherical surface to form a focusing point which is closest to the bottom surface of the lens; spherical surface at the top of the lens with radius R₁The laser penetrates through the spherical surface to form a focusing point which is farthest away from the bottom surface of the lens; the focusing points are uniformly distributed along the axial lead of the lens to form a plurality of focusing points; the laser passes through the corresponding focusing point, then is dispersed and emitted to the inner surface of the light guide water jet water column (7), and then is transmitted inside the light guide water jet water column (7) through total reflection; by the alignment adjustment of the multi-focus lens (1) and the water jet nozzle (5), the focus point (6) is positioned on the axis of the light guide water jet column (7), and the incident laser is ensured not to interfere with the upper surface of the water jet nozzle.

The projection areas of the top spherical surface of the multi-focus lens and each annular spherical surface of the multi-focus lens high-power water-guided laser water optical coupling device along the axial lead are equal, so that the laser energy density of each focus point (6) in the light-guiding water jet water column (7) is equal; the total number of the top spherical surfaces and the annular spherical surfaces of the multi-focus lens is n, and the radius of a plane circle projected by the top spherical surfaces along the axial lead on a horizontal plane is r₁The excircle radius of the plane circular ring of the projection of the outermost annular spherical surface on the horizontal plane along the axis is r_nAt known r_nIn the case of (i) th (value range: 1 to n-1), the formula for calculating the excircle radius of the plane circle (i is 1) and the formula for calculating the excircle radius of the plane circle are

The water-light coupling device of the high-power water-guided laser of the multi-focus lens has the following advantages and effects: after laser beam sees through the glass window of focus lens of the group and the water optical coupling cavity, form a plurality of focus points and the laser energy density of every facula equals in leaded light water jet water column, compare with the spherical lens that only has a focus point in the tradition, the energy that sees through focus lens laser of the group no longer concentrates on a focus point, but disperse in a plurality of focus points, the laser energy density of every facula is showing and is reducing, thoroughly eliminate because of the high emergence that causes leaded light water jet water column to produce the gas explosion of facula energy density, the water jet nozzle damages, the emergence of water optical coupling interrupt phenomenon, can improve the power of laser, and then improve the machining efficiency of water guide laser processing system.

Drawings

Fig. 1 is a schematic structural diagram of a high-power water-guided laser water-optical coupling device with a multi-focus lens, wherein: 1-multi-focus lens, 2-water optical coupling cavity, 3-glass window, 4-high-pressure purified water, 5-water jet nozzle, 6-focusing light column, 7-light guide water jet column, 8-cylindrical parallel laser beam, 9-total reflection laser beam and 10-spherical radius R of top of lens₁11-radius of the annular sphere R at the edge of the lens_n。

FIG. 2 is a top view of the multi-focus lens, which is also a horizontal projection of the top spherical surface and each of the annular spherical surfaces of the multi-focus lens along its axis.

Fig. 3 is a schematic structural diagram of a gas explosion-free water-guided laser processing system employing a multi-focus lens high-power water-guided laser water-optical coupling device, wherein: 21-a laser, 22-a fiber laser beam, 23-a beam expanding collimating lens group, 24-a spectroscope, 25-a multi-focus lens, 26-a water optical coupling cavity, 27-a light guide water jet column, 28-a processed workpiece, 29-a CCD camera, 30-an attenuation sheet, 31-an optical filter and 32-a total reflector.

Detailed Description

The following further describes the embodiments of the present invention with reference to the drawings.

As shown in fig. 1, the high-power water-guided laser water-optical coupling device with a multi-focus lens comprises a multi-focus lens (1), a water-optical coupling cavity (2), a glass window (3), high-pressure purified water (4), a water jet nozzle (5), a focusing light column (6), a light-guiding water jet column (7) and a cylindrical parallel laser beam (2)8) And the like; the multi-focus lens (1) is positioned right above the water-light coupling cavity (2); the water optical coupling cavity (2) is of a cylindrical structure, a cylindrical cavity is arranged inside the water optical coupling cavity, a circular hole (12) is formed in the center of the upper wall of the cavity and used for injecting a laser beam, and a piece of circular plate glass is fixed to the lower surface of the upper wall in a close fit mode to form a glass window (3) of the water optical coupling cavity; a water jet nozzle (5) is fixed at the center of the lower wall of the cavity; a water inlet hole (13) is formed in the cylindrical surface of the water optical coupling cavity, and high-pressure water enters from the water inlet hole and is sprayed out from the water jet nozzle (5) to form a cylindrical light-guide water jet water column (7); the curved surface of the multi-focus lens (1) is formed by intersecting a plurality of spherical surfaces with the same axial lead and different radiuses, and the radius R of the spherical surface at the top part₁At the maximum, the farther from the axis the annular spherical surface has the smaller radius, and the farthest from the axis, that is, the most peripheral annular spherical surface has the radius R_nMinimum; circular spherical radius R at lens edge position_nThe laser passes through the annular spherical surface to form a focusing point which is closest to the bottom surface of the lens; spherical surface at the top of the lens with radius R₁The laser penetrates through the spherical surface to form a focusing point which is farthest away from the bottom surface of the lens; the focusing points are uniformly distributed along the axial lead of the lens to form a plurality of focusing points; the laser passes through the corresponding focusing point, then is dispersed and emitted to the inner surface of the light guide water jet water column (7), and then is transmitted inside the light guide water jet water column (7) through total reflection; by the alignment adjustment of the multi-focus lens (1) and the water jet nozzle (5), the focus point (6) is positioned on the axis of the light guide water jet column (7), and the incident laser is ensured not to interfere with the upper surface of the water jet nozzle.

The coaxial top spherical surface of the multi-focus lens of the high-power water-guided laser water optical coupling device is equal to the projection area of each annular spherical surface along the axial lead, so that the laser energy density of each focus point (6) in the light-guided water jet water column (7) is equal.

FIG. 2 is a top view of the multi-focus lens, which is a horizontal projection view of the top spherical surface and each of the annular spherical surfaces of the multi-focus lens along the axial line, the circle at the center and the circular ring surfaces concentric with the circle at the centerThe products are equal; let the total number n of the top spherical surface and the annular spherical surface of the multi-focus lens be 5, r_n10mm, according to the formula of radius calculationAnd calculating to obtain:

fig. 3 shows an air explosion-free water-jet guided laser processing system, which is composed of a laser (21), an optical fiber laser beam (22), a beam expanding and collimating lens group (23), a spectroscope (24), a multi-focus lens (25), a water-light coupling cavity (26), a light-guide water jet water column (27), a processed workpiece (28), a CCD camera (29), an attenuation sheet (30), a filter (31), and a total reflector (32); laser emitted by a laser (21) enters an optical fiber to form an optical fiber laser beam (22), then passes through a beam expanding collimating lens group (23) and a spectroscope (24) to reach a multi-focus lens (25), the laser beam passing through the multi-focus lens (25) enters a water optical coupling cavity (26) and then is focused into a plurality of focusing points from top to bottom along the inside of a light guide water jet column (27), the focusing points are emitted to the inner surface of the light guide water jet column (27) through divergence, and then transmitted to the surface of a workpiece to be processed (28) along the light guide water jet column (27) through total reflection, so that the workpiece to be processed (28) is processed; light reflected back from the water light coupling cavity (26) through the multi-focus lens (25) is reflected by the spectroscope (24) and the holophote (32), then passes through the optical filter (31) and the attenuation sheet (30) and reaches the CCD camera (29), the camera displays the alignment condition of a laser beam of laser which is emitted into the water light coupling cavity (26) through the multi-focus lens (25) and the light guide water jet column (27), and the relative position of the water jet nozzle and the multi-focus lens (25) in the water light coupling cavity (26) is adjusted through a mechanical transmission device, so that a focus point is positioned inside the light guide water jet column (27).

However, any simple modification, equivalent change and modification made to the above technical solutions according to the technical essence of the present invention still belong to the protection scope of the technical solutions of the present invention.