阅读说明：本技术 一种用于硬脆材料微纳功能表面加工的激光辅助切削机床 (Laser auxiliary cutting machine tool for micro-nano functional surface processing of hard and brittle material ) 是由 冀世军 李晓雅 赵继 范润泽 贺秋伟 代汉达 于 2021-10-06 设计创作，主要内容包括：本发明公开了一种用于硬脆材料微纳功能表面成型的激光辅助切削机床,包括铣刀模块、立柱组模块、底座、载物台组模块、夹紧定位模块、顶盖、激光器；三个立柱组模块固定在底座上且绕z轴均匀分布,载物台组模块分别与三个立柱组模块铰接；立柱组模块上设有由丝杠驱动的滑块,滑块与载物台组模块铰接,使载物台组模块与立柱组模块构成3-PUU并联机构；工件通过夹紧定位模块固定在载物台组模块上且能够在载物台组模块驱动下绕Z轴旋转；顶盖固定在三个立柱组模块上,铣刀模块固定在顶盖上且位于载物台组模块正上方,激光器通过激光器架固定在顶盖上且位于铣刀模块侧方。同时提供一种用于硬脆材料微纳功能表面成型的激光辅助切削机床的加工方法。(The invention discloses a laser auxiliary cutting machine tool for forming a micro-nano functional surface of a hard and brittle material, which comprises a milling cutter module, an upright post group module, a base, an objective table group module, a clamping and positioning module, a top cover and a laser, wherein the milling cutter module is arranged on the base; the three upright post group modules are fixed on the base and uniformly distributed around the z axis, and the objective table group module is respectively hinged with the three upright post group modules; the upright post group module is provided with a slide block driven by a screw rod, and the slide block is hinged with the objective table group module so that the objective table group module and the upright post group module form a 3-PUU parallel mechanism; the workpiece is fixed on the objective table group module through the clamping and positioning module and can rotate around the Z axis under the driving of the objective table group module; the top cover is fixed on the three upright post group modules, the milling cutter module is fixed on the top cover and is positioned right above the objective table group module, and the laser is fixed on the top cover through a laser frame and is positioned on the side of the milling cutter module. Meanwhile, the machining method of the laser auxiliary cutting machine tool for forming the micro-nano functional surface of the hard and brittle material is provided.)

1. A laser auxiliary cutting machine tool for forming a micro-nano functional surface of a hard and brittle material is characterized by comprising a milling cutter module (1), an upright post group module (2), a base (3), an objective table group module (4), a clamping and positioning module (6), a top cover (8) and a laser (9); the three upright post group modules (2) are fixed on the base (3) and are uniformly distributed around the z axis, and the objective table group module (4) is respectively hinged with the three upright post group modules (2) and is positioned at the central position between the upright post group modules (2); a slide block (206) driven by a screw rod (203) is arranged on the upright post group module (2), and the slide block (206) is hinged with the objective table group module (4) to ensure that the objective table group module (4) and the upright post group module (2) form a 3-PUU parallel mechanism; the workpiece (5) is fixed on the objective table group module (4) through the clamping and positioning module (6) and can rotate around the Z axis under the driving of the objective table group module (4); the top cover (8) is fixed on the three upright post group modules (2), the milling cutter module (1) is fixed on the top cover (8) and is positioned right above the objective table group module (4), and the laser (9) is fixed on the top cover (8) through the laser frame (7) and is positioned on the side of the milling cutter module (1).

2. The laser-assisted cutting machine tool for the micro-nano functional surface molding of the hard and brittle material is characterized in that the column group module (2) comprises a lead screw motor (201), a gasket (202), a lead screw (203), a column (204), a guide rail (205), a slide block (206), a connecting rod (207) and a hook hinge (208), the guide rail (205) is fixed on the column (204) along the Z-axis direction, the slide block (206) is in sliding connection with the guide rail (205), the slide block (206) is hinged with the connecting rod (207) through the hook hinge (208), and the other end of the connecting rod (207) is hinged with the stage group module (4) through the hook hinge (208); the screw motor (201) is fixed on the top cover (8), the screw (203) is in meshed transmission with the sliding block (206), and the sliding block (206) slides along the guide rail (205) to do linear reciprocating motion under the driving of the screw motor (201), so that the function of pushing and pulling the connecting rod (207) is realized.

3. The laser-assisted cutting machine tool for forming the micro-nano functional surface of the hard and brittle material is characterized in that the object stage group module (4) comprises a mounting plate (401), a rotary table (402), an object stage (403) and a stepping motor (404), wherein the mounting plate (401) is fixed on the rotary table (402), the rotary table (402) is mounted on the object stage (403) and driven by the stepping motor (404) to rotate, the stepping motor (404) is fixed at the bottom of the object stage (403), three pairs of lugs are arranged on the object stage (403), and the three pairs of lugs are hinged to the upright column group module (2) through a Hooke hinge (208).

4. The laser-assisted cutting machine tool for forming the micro-nano functional surface of the hard and brittle material is characterized in that the clamping and positioning module (6) comprises a pressing block (601), a pressing nut (602), a pressing stud (603) and a positioning block (604); the positioning block (604) is fixed on the mounting plate (401), the positioning block (604) limits three degrees of freedom of x movement, y movement and z rotation of the workpiece (5), the workpiece is pressed and fixed on the mounting plate (401) through the pressing block (601), and the positioning block (604) and the mounting plate (401) achieve the function of positioning the workpiece.

5. The laser-assisted cutting machine tool for forming the micro-nano functional surface of the hard and brittle material is characterized in that the positioning block (604) is provided with a positioning notch matched with the shape of the workpiece (5), and the workpiece (5) is limited to move along the X-axis direction and the Y-axis direction and rotate around the Z-axis through the positioning notch.

6. The laser-assisted cutting machine tool for forming the micro-nano functional surface of the hard and brittle material is characterized in that a strip hole is formed in the pressing block (601) and used for adjusting the assembling position of the pressing stud (603); after the pressing block (601) presses the workpiece (5), the pressing block is fixed on the mounting plate (401) through the pressing nut (602) and the pressing stud (603), and the function of clamping the workpiece is achieved.

7. The machining method of the laser-assisted cutting machine tool for forming the micro-nano functional surface of the hard and brittle material according to claim 1, comprising the following steps of:

step 1, clamping a workpiece on a positioning fixture module, starting a machine tool, setting initial parameter values and initial positions of a system, and inputting a design model;

step 2, analyzing the design model, determining the operation action of the machine tool according to data analysis, forming a numerical control machining program, and achieving the purpose of controlling the movement of the workpiece by controlling the movement of the objective table group module and the 3-PUU parallel mechanism;

step 3, measuring the workpiece processed in the step 2 to form a model, and comparing the model with the design model input in the step 1;

and 4, finishing the machining if the precision requirement is met, and returning to the equipment initialization action in the step 1 if the precision requirement is not met.

8. The machining method of the laser-assisted cutting machine tool for forming the micro-nano functional surface of the hard and brittle material according to claim 7, wherein when the machining direction is changed, the control of the motion of the object carrying module in the step 2 is that: the rotation angle is determined, and then the horizontal movement of the workpiece is determined through the relation between the position of the workpiece and the rotation angle.

9. The machining method of the laser-assisted cutting machine tool for forming the micro-nano functional surface of the hard and brittle material as claimed in claim 7, wherein the motion of the 3-PUU parallel mechanism is cooperatively controlled by three column group modules, and finally the movement of the stage group module along the X, Y, Z axis is realized: and determining respective movement of the three sliding blocks according to the relation between the positions of the sliding blocks of the three upright post group modules and the positions of the object stage group modules, wherein the sliding blocks are driven by the screw rod to do linear reciprocating movement to drive the object stage group modules to move.

Technical Field

The invention belongs to the field of machine manufacturing, and particularly relates to a laser-assisted cutting machine tool for machining a micro-nano functional surface of a hard and brittle material and a machining method thereof.

Background

Due to the special properties of the hard and brittle materials in optical, electronic and mechanical properties, various prepared precision parts are widely applied in related fields. But hard brittle materials are generally classified as difficult to machine materials due to their properties of high hardness and brittleness. Laser-assisted machining is currently widely recognized as one of the economically feasible methods of machining hard and brittle materials. And the application of micro-nano surface functional structures such as black silicon and micro-channels widens the application range of the hard and brittle materials. In recent ten years, surface micro-nano structures are becoming one of the hot research directions for hard and brittle materials.

At present, the research on the laser-assisted cutting forming machine tool for the micro-nano functional surface of the hard and brittle material at home and abroad is not found for a long time. Most of the existing used related equipment stays in the laboratory application stage, the whole machine mainly adopts the self-assembly of a laser and processing equipment, and the degree of the machine does not reach the degree of commercial-grade products, so if a machine tool capable of efficiently processing a microstructure on the surface of a hard and brittle material can be researched, the cost of the machine tool is necessarily greatly reduced, and the application and popularization of the machine tool in the fields of civil life, medical treatment, communication, scientific research and even military industry and national defense are promoted.

Disclosure of Invention

Aiming at the problem that no laser auxiliary cutting forming machine tool for machining the micro-nano functional surface of the commercial grade hard and brittle material is available in the market at present, the invention provides the laser auxiliary cutting machine tool for forming the micro-nano functional surface of the hard and brittle material and the machining method thereof, wherein a 3-PUU parallel mechanism is innovatively adopted, and under the condition that a cutter and a laser are fixed relative to a machine tool, the machining effect that the laser irradiates the to-be-machined area of a workpiece all the time is realized by the cooperation of a rotary table and the 3-PUU parallel mechanism.

The purpose of the invention is realized by the following technical scheme, which is combined with the attached drawings:

a laser auxiliary cutting machine tool for forming a micro-nano functional surface of a hard and brittle material comprises a milling cutter module 1, an upright post group module 2, a base 3, an objective table group module 4, a clamping and positioning module 6, a top cover 8 and a laser 9; the three upright post group modules 2 are fixed on the base 3 and are uniformly distributed around the z axis, and the objective table group module 4 is respectively hinged with the three upright post group modules 2 and is positioned in the central position between the upright post group modules 2; the upright post group module 2 is provided with a slide block 206 driven by a screw rod 203, and the slide block 206 is hinged with the objective table group module 4, so that the objective table group module 4 and the upright post group module 2 form a 3-PUU parallel mechanism; the workpiece 5 is fixed on the objective table group module 4 through the clamping and positioning module 6 and can rotate around the Z axis under the driving of the objective table group module 4; the top cover 8 is fixed on the three upright post group modules 2, the milling cutter module 1 is fixed on the top cover 8 and is positioned right above the objective table group module 4, and the laser 9 is fixed on the top cover 8 through the laser frame 7 and is positioned on the side of the milling cutter module 1.

The 3-PUU parallel mechanism is a 3-degree-of-freedom moving pair-Hooke pair parallel mechanism connection mode, and the 3-PUU mechanism can realize the movement of the object stage group module 4 along the X, Y, Z axis by respectively changing the Z-direction positions of the three sliding blocks 206. The 3-PUU parallel mechanism has a relatively simple structure, has the advantages of high rigidity, high speed, high precision, high flexibility and no accumulated error, and is very suitable for the requirement of laser cutting. Compared with a multi-degree-of-freedom parallel mechanism, the 3-PUU has a more practical application value and a simple structure, and can meet the requirement of plane cutting.

Further, the upright group module 2 includes a screw motor 201, a washer 202, a screw 203, an upright 204, a guide rail 205, a slider 206, a connecting rod 207, and a hooke joint 208, the guide rail 205 is fixed on the upright 204 along the Z-axis direction, the slider 206 is slidably connected with the guide rail 205, the slider 206 is hinged to the connecting rod 207 through the hooke joint 208, and the other end of the connecting rod 207 is hinged to the stage group module 4 through the hooke joint 208; the lead screw motor 201 is fixed on the top cover 8, the lead screw 203 is in meshed transmission with the sliding block 206, the sliding block 206 slides along the guide rail 205 under the driving of the lead screw motor 201 to do linear reciprocating motion, the function of a push-pull connecting rod 207 is realized, and each upright post group module is independently driven by the independent lead screw motor 201.

Further, the object stage group module 4 includes a mounting plate 401, a rotating table 402, an object stage 403, and a stepping motor 404, where the mounting plate 401 is fixed on the rotating table 402, the rotating table 402 is mounted on the object stage 403 and is driven by the stepping motor 404 to rotate, the stepping motor 404 is fixed at the bottom of the object stage 403, three pairs of lugs are arranged on the object stage 403, and the three pairs of lugs are hinged to the column group module 2 through a hooke hinge 208.

Preferably, mounting panel 401 includes clamping piece mounting hole 4011, mounting panel mounting hole 4012, mounting panel locating hole 4013, locating piece mounting hole 4014, locating piece locating hole 4015, clamping piece mounting hole 4011 is along mounting panel 401 circumference evenly distributed, realize the installation clamping piece function, mounting panel mounting hole 4012 is along mounting panel 401 circumference evenly distributed, realize fixed mounting panel 401 function, mounting panel locating hole 4013 realizes mounting panel 401 locate function, mounting block mounting hole 4014 realizes the installation locating piece 604 function, locating piece locating hole 4015 realizes locating piece 604 locate function.

Further, the clamping and positioning module 6 comprises a pressing block 601, a pressing nut 602, a pressing stud 603 and a positioning block 604; the positioning block 604 is fixed on the mounting plate 401, the positioning block 604 limits three degrees of freedom of x movement, y movement and z rotation of the workpiece 5, the pressing block 601 tightly presses and fixes the workpiece on the mounting plate 401, and the positioning block 604 and the mounting plate 401 realize the function of positioning the workpiece.

Preferably, the positioning block 604 is provided with a positioning notch matching with the shape of the workpiece 5, and the workpiece 5 is limited by the positioning notch to move along the X-axis and Y-axis directions and rotate around the Z-axis.

Preferably, the pressing block 601 is provided with a strip hole for adjusting the assembling position of the pressing stud 603; after the pressing block 601 presses the workpiece 5, the pressing block is fixed on the mounting plate 401 through the pressing nut 602 and the pressing stud 603, so that the function of clamping the workpiece is realized.

Preferably, the top surface of the base 3 is provided with three bosses which are uniformly distributed around the z-axis and used for mounting the column group module 2.

The invention also provides a processing method of the laser auxiliary cutting machine tool for forming the micro-nano functional surface of the hard and brittle material, which mainly comprises the following steps:

step 1, clamping a workpiece on a positioning fixture module, starting a machine tool, setting initial parameter values and initial positions of a system, and inputting a design model;

step 2, analyzing the design model, determining the operation action of the machine tool according to data analysis to form a numerical control machining program, and achieving the purpose of controlling the movement of the workpiece by controlling the rotation of the workbench and the movement of the 3-PUU parallel mechanism;

step 3, measuring the workpiece processed in the step 2 to form a model, and comparing the model with the design model input in the step 1;

and 4, finishing the machining if the precision requirement is met, and returning to the equipment initialization action in the step 1 if the precision requirement is not met.

Further, when the processing direction is changed, the controlling of the movement of the object carrying table group module in the step 2 means: the rotation angle is determined, and then the horizontal movement of the workpiece is determined through the relation between the position of the workpiece and the rotation angle.

Further, the motion of the 3-PUU parallel mechanism is cooperatively controlled by the three upright post group modules, and finally the movement of the object stage group module along the X, Y, Z axis is realized: and determining respective movement of the three sliding blocks according to the relation between the positions of the sliding blocks of the three upright post group modules and the positions of the object stage group modules, wherein the sliding blocks are driven by the screw rod to do linear reciprocating movement to drive the object stage group modules to move.

The invention has the advantages that:

1. aiming at the current situation that the domestic laser-assisted machining machine tool for hard and brittle materials is still in a laboratory stage, a special laser-assisted cutting machine tool for hard and brittle materials is designed, so that the machine tool is more integrated and commercialized, the appearance of the equipment is optimized, the requirement of commercial products is met, meanwhile, the power parameter of a laser, the motion of a cutter and the like are controlled, and the fusion mode of the laser and the machining equipment is convenient to operate, control, safe, reliable and attractive in appearance;

2. different from the traditional xyz coordinate machine tool, the machine tool design innovatively adopts a 3-PUU parallel mechanism, the application of the 3-PUU parallel mechanism in the machine tool design is tried, the moving freedom degree of a workpiece is realized by controlling the 3-PUU parallel mechanism, and the rotating freedom degree of the workpiece is realized by using a rotary table, so that the control of the workpiece is realized; compared with a multi-degree-of-freedom parallel mechanism, the 3-PUU has a more practical application value and a simple structure, and can meet the requirement of plane cutting.

3. Under the condition that the cutter and the laser are fixed relative to the machine tool, the machining effect that the laser always irradiates on the area to be machined is achieved by the matching of the rotary table and the sliding block.

Drawings

FIG. 1 is a general structural schematic diagram of a laser-assisted cutting machine tool for micro-nano functional surface forming of a hard and brittle material

FIG. 2 is a schematic view of the column set module

FIG. 3 is a schematic view of the stage set module

FIG. 4 is a schematic view of clamping the workpiece of the stage assembly module

FIG. 5 is a top view of the mounting plate

FIG. 6 is a schematic view of the base structure

FIG. 7 is a flow chart of a processing method of a laser-assisted cutting machine tool for forming a micro-nano functional surface of a hard and brittle material

FIG. 8 is a schematic diagram of the motion principle of the 3-PUU parallel mechanism

FIG. 9 is a diagram showing the movement analysis of the 3-PUU parallel mechanism during the processing

In the figure:

1. milling cutter module 2, upright post group module 3, base 4, objective table group module 5, workpiece 6, clamping and positioning module 7, laser frame 8, top cover 9, laser module 201, lead screw motor 202, gasket 203, lead screw 204, upright post 205, guide rail 206, sliding block 207, connecting rod 208, hooke hinge 401, mounting plate 402, rotary table 403, objective table 404, stepping motor 601, pressing block 602, pressing nut 603, pressing stud 604, positioning block 4011, clamping piece mounting hole 4012, mounting plate mounting hole 4013, mounting plate positioning hole 4014, positioning block mounting hole 4015, positioning block positioning hole 4015

Detailed Description

The embodiments are further illustrated by the following figures and examples.

The motion principle of the machine tool is as follows: the tool and the laser are fixed and the workpiece rotates around the axis of the tool. The method has simple structure, can reduce energy consumption and improve precision. The specific implementation method comprises the following steps:

a laser auxiliary cutting machine tool for forming a micro-nano functional surface of a hard and brittle material comprises a milling cutter module 1, an upright post group module 2, a base 3, an objective table group module 4, a workpiece 5, a clamping and positioning module 6, a top cover 8 and a laser 9; the three upright post group modules 2 are fixed on the base 3 and are uniformly distributed around the z axis, and the objective table group module 4 is respectively hinged with the three upright post group modules 2 and is positioned in the central position between the upright post group modules 2; the upright post group module 2 is provided with a slide block 206 driven by a screw rod 203, and the slide block 206 is hinged with the objective table group module 4, so that the objective table group module 4 and the upright post group module 2 form a 3-PUU parallel mechanism; the workpiece 5 is fixed on the objective table group module 4 through the clamping and positioning module 6 and can rotate around the Z axis under the driving of the objective table group module 4; the top cover 8 is fixed on the three upright post group modules 2, the milling cutter module 1 is fixed on the top cover 8 and is positioned right above the objective table group module 4, and the laser 9 is fixed on the top cover 8 through the laser frame 7 and is positioned on the side of the milling cutter module 1.

The 3-PUU parallel mechanism is a 3-degree-of-freedom moving pair-Hooke pair parallel mechanism connection mode, and the 3-PUU mechanism can realize the movement of the object stage group module 4 along the X, Y, Z axis by respectively changing the Z-direction positions of the three sliding blocks 206. The 3-PUU parallel mechanism has a relatively simple structure, has the advantages of high rigidity, high speed, high precision, high flexibility and no accumulated error, and is very suitable for the requirement of laser cutting. Compared with a multi-degree-of-freedom parallel mechanism, the 3-PUU has a more practical application value and a simple structure, and can meet the requirement of plane cutting.

Further, the upright group module 2 includes a screw motor 201, a washer 202, a screw 203, an upright 204, a guide rail 205, a slider 206, a connecting rod 207, and a hooke joint 208, the guide rail 205 is fixed on the upright 204 along the Z-axis direction, the slider 206 is slidably connected with the guide rail 205, the slider 206 is hinged to the connecting rod 207 through the hooke joint 208, and the other end of the connecting rod 207 is hinged to the stage group module 4 through the hooke joint 208; the lead screw motor 201 is fixed on the top cover 8, the lead screw 203 is in meshed transmission with the sliding block 206, the sliding block 206 slides along the guide rail 205 under the driving of the lead screw motor 201 to do linear reciprocating motion, the function of a push-pull connecting rod 207 is realized, and each upright post group module is independently driven by the independent lead screw motor 201.

Further, the object stage group module 4 includes a mounting plate 401, a rotating table 402, an object stage 403, and a stepping motor 404, where the mounting plate 401 is fixed on the rotating table 402, the rotating table 402 is mounted on the object stage 403 and is driven by the stepping motor 404 to rotate, the stepping motor 404 is fixed at the bottom of the object stage 403, three pairs of lugs are arranged on the object stage 403, and the three pairs of lugs are hinged to the column group module 2 through a hooke hinge 208.

Preferably, mounting panel 401 includes clamping piece mounting hole 4011, mounting panel mounting hole 4012, mounting panel locating hole 4013, locating piece mounting hole 4014, locating piece locating hole 4015, clamping piece mounting hole 4011 is along mounting panel 401 circumference evenly distributed, realize the installation clamping piece function, mounting panel mounting hole 4012 is along mounting panel 401 circumference evenly distributed, realize fixed mounting panel 401 function, mounting panel locating hole 4013 realizes mounting panel 401 locate function, mounting block mounting hole 4014 realizes the installation locating piece 604 function, locating piece locating hole 4015 realizes locating piece 604 locate function.

Further, the clamping and positioning module 6 comprises a pressing block 601, a pressing nut 602, a pressing stud 603 and a positioning block 604; the positioning block 604 is fixed on the mounting plate 401, the positioning block 604 limits three degrees of freedom of x movement, y movement and z rotation of the workpiece 5, the pressing block 601 tightly presses and fixes the workpiece on the mounting plate 401, and the positioning block 604 and the mounting plate 401 realize the function of positioning the workpiece.

Preferably, the positioning block 604 is provided with a positioning notch matching with the shape of the workpiece 5, and the workpiece 5 is limited by the positioning notch to move along the X-axis and Y-axis directions and rotate around the Z-axis.

Preferably, the pressing block 601 is provided with a strip hole for adjusting the assembling position of the pressing stud 603; after the pressing block 601 presses the workpiece 5, the pressing block is fixed on the mounting plate 401 through the pressing nut 602 and the pressing stud 603, so that the function of clamping the workpiece is realized.

Preferably, the top surface of the base 3 is provided with three bosses which are uniformly distributed around the z-axis and used for mounting the column group module 2.

The invention also provides a processing method of the laser auxiliary cutting machine tool for forming the micro-nano functional surface of the hard and brittle material, which mainly comprises the following steps:

step 1, clamping a workpiece on a positioning fixture module, starting a machine tool, setting initial parameter values and initial positions of a system, and inputting a design model;

step 2, analyzing the design model, determining the operation action of the machine tool according to data analysis to form a numerical control machining program, and achieving the purpose of controlling the movement of the workpiece by controlling the rotation of the rotary table and the movement of the 3-PUU parallel mechanism;

step 3, measuring the workpiece processed in the step 2 to form a model, and comparing the model with the design model input in the step 1;

and 4, finishing the machining if the precision requirement is met, and returning to the equipment initialization action in the step 1 if the precision requirement is not met.

Further, when the processing direction is changed, the controlling of the movement of the object carrying table group module in the step 2 means: the rotation angle is determined, and then the horizontal movement of the workpiece is determined through the relation between the position of the workpiece and the rotation angle.

Further, the motion of the 3-PUU parallel mechanism is controlled by the lead screw motor 201 of the three upright post group modules 2, and finally the motion of the movable platform along the X, Y, Z axis is realized: according to the relation between the slide block position of the three upright post group module 2 and the object stage group module position, the respective movement of the three screw motors 201 is determined, the slide block 206 makes a linear reciprocating movement under the driving of the screw motors 201 by using the screws 203 to realize the function of the push-pull connecting rod 207, and the push-pull connecting rod 207 drives the object stage group module to realize the movement of the object stage group module.

Example 1

The selected processing object is a simple two-dimensional micro-channel structure, and the structure is characterized in that: most are simple two-dimensional patterns, requiring surface roughness of the flow channel to control fluid flow rate. And selecting milling for the machining mode. Because the cutter rotates in the milling process, the laser auxiliary heating mode in the process that the laser path is in the cutter cannot be adopted, and therefore the heating mode is selected to be a preheating heating mode. Because the irradiation point of the laser is always positioned on the surface to be processed, when the cutter translates on the surface of the workpiece, if the irradiation position of the laser is always unchanged, the laser cannot irradiate the surface to be processed and even irradiates other parts of the cutter or a machine tool when the processing direction is changed, so that loss is caused. In order to solve the problem that the laser point is not matched with the cutter path, a rotational degree of freedom needs to be added to meet the requirement that the laser irradiation point is always in the advancing direction of the cutter, so that the cutter and the laser are adopted for fixation, and the workpiece rotates around the axis of the cutter. The method has simple structure, can reduce energy consumption and improve precision. The specific implementation method of the machine tool comprises the following steps:

as shown in fig. 1, a laser-assisted cutting machine tool for micro-nano functional surface forming of hard and brittle materials comprises a milling cutter module 1, an upright post group module 2, a base 3, a stage group module 4, a workpiece 5, a clamping and positioning module 6, a laser frame 7, a top cover 8 and a laser 9, wherein the base 3 is provided with three uniformly distributed bosses on the top surface for mounting the upright post group module 2, the upright post group module 2 has 3 groups in total, the three bosses are fixed on the base 3 and are uniformly distributed around a z-axis, the purpose is to provide driving for a sliding block, the stage group module 4 is hinged with the upright post group module 2 and is positioned at the center position of the upright post group module 2, the stage group module 4 and the upright post group module 2 form a 3-PUU parallel mechanism, and a 3-PUU (P-prism pair of motion, U-hook pair of parallel mechanism of hook pair of parallel mechanism of hook pair of, the 3-PUU mechanism can realize the movement of the movable platform along the X, Y, Z shaft by changing the positions of the three sliding blocks, the parallel mechanism has a relatively simple structure, and has the advantages of high rigidity, high speed, high precision, high flexibility and no accumulated error, thereby being very suitable for the requirements of laser cutting. Compared with a multi-degree-of-freedom parallel mechanism, the 3-PUU has a more practical application value and a simple structure, and can meet the requirement of plane cutting. The workpiece 5 is fixed on the object stage group module 4 through the clamping and positioning module 6, the top cover 8 is fixed on the upright post group module 2, the milling cutter module 1 is fixed on the top cover 8 and is positioned right above the object stage group module 4, the laser frame 7 is fixed on the top cover 8 and is positioned on the side of the milling cutter module 1, and the laser 9 is fixed on the laser frame 7.

As shown in fig. 2, the column set module 2 includes a screw motor 201, a spacer 202, a screw 203, a column 204, a guide rail 205, a slider 206, a connecting rod 207, and a hooke joint 208, the guide rail 205 is fixedly connected to the column 204, the slider 206 is slidably connected to the guide rail 205, the slider 206 is hinged to the connecting rod 207 by the hooke joint 208, the screw motor 201 is fixed to the top cover 8, the slider can be controlled to move to a specified position at a specified speed by controlling the on-off time and the pulse frequency of the screw motor, and the slider 206 is driven by the screw 203 to perform a linear reciprocating motion by the screw motor 201, thereby achieving the function of pushing and pulling the connecting rod 207. The upright column occupies a large volume, the material is HT200, the sliding block is mainly responsible for pushing and pulling the connecting rod under the control of the screw rod, the stress is not large, the material with small mass is selected to reduce the inertia in the movement process, the material is aluminum alloy 5083-H112, the connecting rod bears the high-frequency pulling and pressing load in a small amplitude, the connecting rod is not complex in structure, and the processing manufacturability is good, so that the material is 45 steel.

As shown in fig. 3, the object stage group module 4 includes a mounting plate 401, a turntable 402, an object stage 403, and a stepping motor 404, where the object stage group module 4 is used to clamp a workpiece and provide a required rotational degree of freedom for processing, the mounting plate 401 is fixed on the turntable 402, the turntable 402 is driven by the stepping motor 404 to rotate, the turntable 402 is fixed on the object stage 403, the stepping motor 404 is fixed on the object stage 403, and three pairs of lugs of the object stage 403 are hinged to the column group module 2 through hooke joints 208.

As shown in fig. 4, the clamping and positioning module 6 includes a pressing block 601, a pressing nut 602, a pressing stud 603, and a positioning block 604, the positioning block 604 is fixed on the mounting plate 401, the positioning block 604 limits three degrees of freedom of x movement, y movement, and z rotation of the workpiece 5, the mounting plate 401 limits three degrees of freedom of z movement, x rotation, and y rotation of the workpiece 5, the positioning block 604 and the mounting plate 401 realize a workpiece positioning function, and the pressing block 601 is fixed on the mounting plate 401 by using the pressing nut 602 and the pressing stud 603, so as to realize a workpiece clamping function.

As shown in fig. 5, mounting panel 401 includes clamping piece mounting hole 4011, mounting panel mounting hole 4012, mounting panel locating hole 4013, locating piece mounting hole 4014, locating piece locating hole 4015, clamping piece mounting hole 4011 is along mounting panel 401 circumference evenly distributed, realize installation clamping piece function, mounting panel mounting hole 4012 is along mounting panel 401 circumference evenly distributed, realize fixed mounting panel 401 function, mounting panel locating hole 4013 realizes mounting panel 401 locate function, locating piece mounting hole 4014 realizes installation locating piece 604 function, locating piece locating hole 4015 realizes locating piece 604 function. The top surface of the mounting plate is used as a workpiece positioning surface and has certain flatness requirement; secondly for the installation of adaptation not equidimension work piece, the hole distribution of installation clamping piece is fit: the workpiece is not convenient to clamp if the workpiece is too loose, and the processing cost is increased if the workpiece is too dense; mounting holes are also reserved for fixing the mounting plate on the rotary table; finally, mounting holes are reserved for the positioning block and the positioning pin thereof. The mounting plate should also be lightweight to reduce the rotational inertia of the turntable.

As shown in fig. 6, the base 3 has three uniformly distributed bosses on the top surface for mounting the column set, and the bosses can reduce the area of the milled plane on the top surface; the bottom surface is also provided with a notch for reducing the processing area. The base is used as a main part for bearing the weight of the machine tool, and the stability requirement is high; the base has no excessively fine size requirements on the total length, the total width and the total height, but has higher requirements on the uniformity and the distance of the three bosses; the whole volume of the part is large, the part needs to be subjected to milling and drilling processes, and the part is used as a pressed support, and HT200 is selected as a comprehensive consideration material.

3-calculation of the degree of freedom of the PUU parallel mechanism: the degree of freedom of a 3-PUU parallel mechanism is tested, in the mechanism, a movable component comprises three sliding blocks, three connecting rods and a movable platform, and the number of the sliding blocks, the connecting rods and the movable platform is 7; the V-level pair is a space moving pair, and the number of the V-level pairs is 3; the IV-level pair is a Hooke pair, the number of the IV-level pairs is 6, and according to a degree of freedom calculation formula:

n＝6n-5P₅-4P₄-3P₃-2P₂-P₁

the calculated degree of freedom of the mechanism is

n＝6×7-5×3-4×6＝3

In the process of milling the two-dimensional micro-channel, a tool and a workpiece need to move freely in a horizontal plane, and move in a vertical direction during tool retracting action, so that the analysis machine tool needs the moving freedom degrees in the x direction, the y direction and the z direction, wherein the z-axis direction is only needed when the machine tool is not processed, and the machine tool only needs 2.5 axes.

The driving number is equal to the degree of freedom, the mechanism can move definitely, and the degree of freedom meets the requirement.

As shown in fig. 8, the theoretical principle of the 3-PUU parallel mechanism controlling the motion of the brake platform is as follows:

different from the traditional xyz coordinate, the driving motors of the 3-PUU parallel mechanism do not respectively and independently control the movement in a certain direction, so that the relation between the position of the sliding block and the position of the movable platform needs to be found, and the position of the movable platform can be controlled by controlling the position of the sliding block.

In order to solve the position relation between the platform and the sliding block, firstly, the 3-PUU parallel mechanism is structurally simplified and a coordinate system is constructed. Assuming that three sliding blocks respectively move up and down along the central axis directions of three guide rails of 1 axis, 2 axes and 3 axes, simplifying the sliding blocks into A₂、B₂、 C₂Three points, connecting rod A₁A₂、B₁B₂、C₁C₂Respectively connected with the sliding block and the movable platform, and the connection points with the movable platform are respectively A₁、 B₁、C₁The moving plane of the moving platform intersects with the axes 1, 2 and 3 respectively at three points A, B, C.

A right-handed rectangular coordinate system O-XYZ is established by taking the central point O of a regular triangle formed by the intersection points of the three axes and the fixed platform as the origin, and the X axis is parallel to A₁C₁Direction to move the platform A₁B₁C₁Midpoint O₁Establishing a moving coordinate system O for the origin₁-X₁Y₁Z₁Each axial direction is parallel to the X, Y, Z axis

Assuming that the side length of the regular triangle of the fixed platform is L, the side length of the regular triangle of the movable platform is L₁Length L of connecting rod₂。

Taking the 1-axis as an example,at the beginning of O₁Relative to a fixed coordinate system of

According to the side length formula and the midpoint definition of the regular triangle, the coordinate of A relative to the fixed coordinate system is

According to the knowledge of coordinate change, A and A₁Relative to the position of the moving coordinate system

Then | AA₁If is |, then

At Δ AA₁A₂In the middle, it can be obtained by the Pythagorean theorem

Similarly, | BB can be derived₂And CC₂The formula of | the position relationship between the three sliders and the platform is as follows

In the case of a defined machine tool profile, L₁And L₂All the sliding blocks are constant known, so that the position of the movable platform can be controlled by the three sliding blocks through the above formula.

As shown in fig. 9, the principle of controlling the motion and rotation angle of the platform is:

in the actual processing movement process, the translation matching of the rotary table and the movable platform is also needed, in order to determine the relation between the position of the platform and the rotation angle, firstly, the model is simplified, and a coordinate system is established. The fixed coordinate system O-XY is fixedly connected under the machine tool frame, and the tool nose coordinate P is (X)_o，Y_o) Moving coordinate system O₁-X₁Y₁Fixedly connected to the moving platform, O₁The coordinates are

According to the coordinate change knowledge, the coordinate of the P point relative to the moving coordinate system at the moment is

For convenience of presentation, contract

The coordinate of the point P relative to the moving coordinate system is

P(X₁，Y₁)＝(u，v)

Then, the moving coordinate system O₁-X₁Y₁Around O₁Point rotating alpha angle to moving coordinate system O₁-X₂Y₂According to the knowledge of coordinate transformation, the point P is relative to the moving coordinate system O₁-X₂Y₂Has the coordinates of

P(X₂，Y₂)＝(u cosα+v sinα，v cosα-u sinα)

To achieve O₁-X₁Y₁Effect of rotation around point P, translation of coordinate system O₁-X₂Y₂To O₂-X₃Y₃So that P (X)₁，Y₁) And P (X)₂，Y₂) Equality, simple calculation requires that O be equal₁Along X₂Direction translation

(u cosα+vsinα)-u

Along Y₂Direction translation

(v cosα-u sinα)-v

But the two translations are along X₂And Y₂Two directions, which need to be converted to X and Y (or X)₁And Y₁) In the direction, the movement can be translated into the movement of the movable platform coordinate. Depending on the angular relationship, the platform is required to be along X (or X)₁) Direction movement

[(u cosα+v sinα)-u]cosα-[(v cosα-u sinα)-v]sinα (1)

Along Y (or Y)₁) Direction movement

[(u cosα+v sinα)-u]sinα+[(v cosα-u sinα)-v]cosα (2)

Simplifying the formulas (1) and (2) to obtain a formula f (alpha) for translating the movable platform along the X direction and a formula g (alpha) for translating the movable platform along the Y direction when the platform rotates an alpha angle

In the actual processing process, the material is processed,andcan be obtained by in situ measurement, and X_oAnd Y_oThe relation between the platform position and the rotation angle is obtained in a fixed value mode.

Example 2

A processing method of a laser auxiliary cutting machine tool for forming a micro-nano functional surface of a hard and brittle material mainly comprises the following steps:

step 1, selecting a cutter according to a machined workpiece, mounting the cutter at a fixed position, and adjusting the power of a laser according to the material of the workpiece and the machining requirement;

step 2, clamping a workpiece on a positioning fixture module, wherein the workpiece has the freedom degrees of moving along three axes and rotating around a vertical axis due to the working principle of a machine tool that a cutter and a laser are fixed, and when the machine tool is started, the initial position of the workpiece and other initial parameter values of a system need to be set, and a design model is input at the same time;

step 3, analyzing a design model, determining respective movement of the three lead screw motors 201 according to the relation between the position of the sliding block and the position of the workbench, determining movement of the stepping motor 404 according to the relation between the position of the platform and a rotating angle, finally determining the operation action of the workpiece according to data analysis to form a numerical control machining program, and finally achieving the purpose of controlling the movement of the workpiece through the rotation of the workbench and the movement of the sliding block;

step 4, measuring the workpiece processed in the step 3 to form a model, and comparing the model with the design model input in the step 2;

and 5, finishing the machining if the machining requirement is met, and returning to the equipment initialization action in the step 2 if the machining requirement is not met.