Laser combined machining device and method for efficient grinding-polishing of microstructure

Abstract

The invention discloses a laser composite machining device and method for efficient grinding-polishing of a microstructure, and belongs to the technical field of precision machining. The laser composite precision machining device comprises a laser composite precision machining module which specifically comprises a laser device, a collimator, a main shaft and a texture grinding wheel, and the texture grinding wheel is arranged on the main shaft; a lens mounting frame is arranged inside the lens, a first beam splitter, a second beam splitter, a third beam splitter and a reflector are sequentially arranged on the lens mounting frame, a first focus lens is arranged on a beam splitting optical path of the first beam splitter, a second focus lens is arranged on a beam splitting optical path of the second beam splitter, and a third focus lens is arranged on a beam splitting optical path of the third beam splitter. And a fourth focusing mirror is arranged on a reflecting light path of the reflecting mirror. In the grinding process, in-situ laser is used for achieving grinding-polishing integration, the problems that in the ultra-precision machining process, machining is conducted firstly, then polishing is conducted, efficiency is low, the process is complex, and the equipment adaptability is poor are solved, and the machining period of the microstructure is shortened.

Description

Technical Field

[0001] The invention belongs to the technical field of precision machining, and in particular relates to a laser composite machining method and device for high-efficiency grinding-polishing of microstructures of hard, brittle and difficult-to-machine materials. Background Art

[0002] C f Ceramic-based composites such as SiC and other hard-to-process materials, such as nickel-based high-temperature alloys, have the advantages of high temperature resistance, high strength, corrosion resistance, and low density. Various microstructures are prepared on the surface of the materials to achieve drag reduction and heat dissipation effects. They are widely used in defense industry, aerospace, high-end automobiles and other fields. However, due to the small scale of the microstructure and high consistency requirements, higher and higher requirements are placed on processing. At present, the processing of microstructures is mainly based on conventional processing methods. Conventional processing has problems such as large tool wear and poor processing surface quality. Secondary trimming is often required, so the processing efficiency is also low. Studies have shown that lasers can effectively improve the machinability of hard and brittle materials, improve the processing surface quality, and reduce tool wear. At present, there is no one who uses lasers for integrated microstructure processing-polishing of hard and brittle materials. At present, some people have made improvements to laser polishing technology. For example, a laser polishing machine and a polishing method for the laser polishing machine (CN117483957A), although they can polish objects of multiple sizes, still belong to the process of secondary finishing; a laser polishing device for inner holes (CN218016412U), but it does not specify how large the inner hole can be polished and needs to be used with specific equipment; an ultrafast laser polishing method for ceramic-based composite materials (CN108890138B), the laser polishing effect in this patent is obvious, but the laser processing angle of the material is only 90°-70°; a femtosecond laser precision forming processing system for complex components of hard and brittle materials (CN110788500B) has a relatively complex process and requires electrochemical assistance during laser polishing. Therefore, there is an urgent need for a processing method and device that integrates processing and laser polishing and improves grinding quality and efficiency, so as to achieve high-efficiency and high-quality grinding-polishing effects of array microstructures when processing the microstructures of hard, brittle and difficult-to-process materials. Therefore, the invention of a laser composite processing method and device for efficient grinding-polishing of microstructures is necessary. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a laser composite processing device and method for efficient grinding and polishing of microstructures. During the grinding process, in-situ laser is used to achieve integrated grinding and polishing, which solves the problems of low efficiency of first processing and then polishing, complex process, poor equipment adaptability, etc. in ultra-precision machining, and reduces the processing cycle of the microstructure.

[0004] A laser composite processing device for efficient grinding and polishing of microstructures comprises a laser composite precision processing module, a driving module, a safety protection module, a supporting unit, a connecting unit and an observation module. The laser composite precision processing module comprises a laser, a collimator, a spindle and a textured grinding wheel. The textured grinding wheel is arranged on the spindle, and a lens mounting frame is arranged inside. The lens mounting frame is sequentially arranged with a first beam splitter, a second beam splitter, a third beam splitter and a reflector. A first focusing mirror is arranged on the light splitting path of the first beam splitter, a second focusing mirror is arranged on the light splitting path of the second beam splitter, a third focusing mirror is arranged on the light splitting path of the third beam splitter, and a fourth focusing mirror is arranged on the reflecting path of the reflector. The laser light beam emitted by the laser enters the internal optical cavity of the textured grinding wheel through the collimator, a part of the energy is transmitted through the first beam splitter to the lower second beam splitter, and a part of the energy is reflected through the focusing mirror to form a focus on the same surface of the vertex of the texture.

[0005] The support unit includes a marble gantry and a marble workbench; the drive module includes an X-axis linear slide, a Y-axis stepper motor, and a Z-axis stepper motor; the connection unit includes a processing platform, an adapter plate I, a connection plate II, a connection plate I, a laser support frame, and an adapter plate I; the observation module includes a manual slide and an industrial camera; the safety protection module includes a protective cover and a mounting rod.

[0006] The laser is fixedly arranged on a connecting plate II through a laser supporting frame, and the connecting plate II is arranged on a marble workbench.

[0007] The spindle is arranged on a connecting plate I through a spindle fixing frame, and the connecting plate I is connected to a Z-axis stepping motor.

[0008] The X-axis linear slide is arranged on a marble workbench, and the Y-axis stepper motor is arranged on the X-axis linear slide.

[0009] A liquid circulation channel is arranged inside the protective cover and is connected to a cooling system.

[0010] A laser composite processing method for microstructure efficient grinding-polishing adopts the laser composite processing device for microstructure efficient grinding-polishing, comprising the following steps:

[0011] Step 1: Fix the workpiece on the processing platform, install the texture grinding wheel on the spindle, start the control system, move the X-axis linear slide, Y-axis stepper motor, and Z-axis stepper motor, rotate the spindle, and perform the tool setting process through the industrial camera of the observation module, so that the rotating texture grinding wheel is close to the pre-processing position on the workpiece surface;

[0012] Step 2: Fix the laser on the laser support frame, adjust the position so that the laser and the collimator are in the same plane, and perform infrared preview of the laser;

[0013] Step three, input the CNC program, the protective cover descends and covers the processing area, the coolant circulates inside the protective cover, the laser is started, the light beam is introduced into the grinding wheel through the optical path, and reaches the first beam splitter. Part of the energy is reflected through the first focusing mirror and focused on the same plane of the grinding wheel texture, and part of the energy is transmitted to the second beam splitter and passes through the third beam splitter and the reflecting mirror in turn, and is focused on the same plane through the second focusing mirror, the third focusing mirror, and the fourth focusing mirror; during the grinding wheel processing, in-situ laser polishing is realized, and the laser energy emitted from the non-processing position hits the light-absorbing coating inside the protective cover and is absorbed by the protective cover.

[0014] Through the above design scheme, the present invention can bring the following beneficial effects:

[0015] 1. A method for integrating efficient microstructure grinding and laser polishing is proposed. A multi-angle beam splitting chamber is designed inside the grinding wheel to guide the laser light path and achieve the effect of laser polishing. The array microstructure is processed by a textured grinding wheel, and a laser is introduced inside. Combined with laser polishing, while processing the array microstructure, the burrs, chip adhesion and other defects of the microstructure are trimmed to improve the quality of the processed surface and achieve high-efficiency and high-quality grinding-polishing integration of the microstructure.

[0016] 2. A multi-angle beam splitting chamber is designed, in which optical device beam splitters and focusing mirrors are embedded. Laser is introduced into the spindle and then introduced to the microstructure surface through the multi-angle beam splitting chamber, realizing laser polishing of array microstructure processing. An optical bracket is placed inside the textured grinding wheel. The bracket has two mounting positions. The lower mounting position is equipped with a focusing mirror, and the upper mounting position is equipped with a beam splitter or a reflector with different transmittances. The center of the beam splitter and the reflector is coaxial with the center of the focusing mirror. After the laser passes through the spindle, it is introduced into the grinding wheel. Through the action of the beam splitter, part of the energy of the laser is transferred to the next beam splitter, and part of the reflected light passes through the focusing mirror through the gap structure between the grinding wheel textures to form a laser beam. The focus point is at the same position on the top of the grinding wheel texture. During the high-speed operation of the grinding wheel, texture processing and laser shaping are performed alternately. The burrs and chip adhesion left by the texture processing are improved through laser shaping to improve the processing surface quality, realizing efficient grinding and polishing of the microstructure.

[0017] 3. An internal cooling protective cover is added above the processing area. The protective cover can well cover the processing area. The protective cover material has a high melting threshold, and the inner surface is covered with a carbon black layer with a high infrared absorption rate, which effectively reduces the laser energy. There is a liquid channel inside, and the temperature of the protective cover is reduced by connecting the coolant circulation system. When the laser passes through the inside of the grinding wheel to reach the protective cover through the action of the beam splitter, the energy is relatively small. When it hits the protective cover, it first passes through the carbon black layer to absorb most of the infrared band, which greatly reduces the laser energy. After passing through the internal coolant, it cannot cause damage to the protective cover and transfers heat out; during the processing, the laser beam on the grinding wheel is in a defocused state at a position higher or lower than the texture, with low energy, achieving effective protection and ensuring safety during laser processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention is further described below with reference to the accompanying drawings and specific embodiments:

[0019] Figure 1 It is a schematic structural diagram of the laser compound precision machining module of the laser compound machining device for efficient grinding-polishing of microstructures of the present invention.

[0020] Figure 2 This is a schematic diagram of the laser installation structure of the laser composite processing device for efficient grinding-polishing of microstructures of the present invention.

[0021] Figure 3 This is a schematic diagram of the overall external structure of the laser composite processing device for efficient grinding and polishing of microstructures of the present invention.

[0022] Figure 4 This is a schematic diagram of the internal structure of the textured grinding wheel of the laser composite processing device for efficient grinding-polishing of microstructures of the present invention.

[0023] Figure 5 This is a schematic diagram of the laser light path of the laser composite processing device for efficient grinding and polishing of microstructures of the present invention.

[0024] In the figure, 1-marble gantry, 2-marble workbench, 3-manual slide, 4-adapter plate I, 5-industrial camera, 6-textured grinding wheel, 7-machining platform, 8-X-axis linear slide, 9-Y-axis stepper motor, 10-spindle, 11-connecting plate I, 12-collimator, 13-laser, 14-laser support frame, 15-connecting plate II, 16-Z-axis stepper motor, 17-lens mounting frame, 18-protective cover, 19-mounting rod, 20-adapter plate I, 23-first focusing mirror, 24-second focusing mirror, 25-fourth focusing mirror, 26-third focusing mirror, 27-first beam splitter, 28-second beam splitter, 29-third beam splitter, 30-reflector. DETAILED DESCRIPTION

[0025] Laser composite processing device for efficient grinding and polishing of microstructures, such as Figure 1-Figure 5 As shown, it includes a laser composite precision processing module, a driving module, a safety protection module, a support unit, a connection unit and an observation module. The laser composite precision processing module includes a laser 13, a collimator 12, a spindle 10 and a textured grinding wheel 6. The support unit includes a marble gantry 1 and a marble workbench 2; the driving module includes an X-axis linear slide 8, a Y-axis stepper motor 9, and a Z-axis stepper motor 16; the connection unit includes a processing platform 7, an adapter plate I4, a connecting plate II15, a connecting plate I11, a laser support frame 14 and an adapter plate I20; the observation module includes a manual slide 3 and an industrial camera 5; the safety protection module includes a protective cover 18 and a mounting rod 19.

[0026] Specifically, the marble workbench 2 is connected with four feet and placed on a horizontal workbench plane, and the marble gantry 1 is fixed on the marble workbench 2 by bolts.

[0027] The X-axis straight slide 8 is connected to the marble workbench 2 through four bolts, the Y-axis stepper motor 9 is fixed on the X-axis straight slide 8 through four bolts, and the processing platform 7 is fixed on the Y-axis stepper motor 9.

[0028] The manual slide 3 is fixed on the marble gantry 1, the adapter plate Ⅰ4 is fixed on the manual slide 3 by four bolts, and the industrial camera 5 is fixed on the adapter plate Ⅰ4.

[0029] The Z-axis stepper motor 16 is fixed on the marble gantry 1, the connecting plate Ⅰ11 is connected to the Z-axis stepper motor 16, the spindle fixing frame is connected to the connecting plate Ⅰ11, the spindle 10 is fixed on the spindle fixing frame, the textured grinding wheel 6 is fixed on the spindle 10, the interior of the textured grinding wheel 6 is hollow, and an optical mounting frame 17 is fixed on the mounting frame, on which beam splitters, focusing mirrors and reflecting mirrors with different transmission effects are installed.

[0030] The adapter plate II 15 is connected to the marble workbench 2, the laser support frame 14 is fixed on the adapter plate II 15, the laser 13 is placed on the laser support frame 14, and the collimator 12 is fixed on the spindle 10. The protective cover 18 is connected to the adapter plate I 20 on the marble gantry 2 through the connecting rod 19.

[0031] The laser composite precision machining module emits a laser beam from a laser 13, which enters the interior of the texture grinding wheel 6 through a collimator 12, transmits part of the energy through the first beam splitter to the next beam splitter, and part of the energy is reflected through the focusing mirror to be focused on the same surface of the texture vertex. As the spindle 10 rotates, the machining-polishing cycle is completed to achieve in-situ laser polishing.

[0032] The stepper motor and linear slide of the driving module move to control the movement of the workpiece and complete the grinding process of the array texture.

[0033] The observation unit mainly includes an industrial camera. Before processing, the position is adjusted by a manual slide to complete the tool setting process. In order to ensure that the energy is attenuated while the focusing energy is consistent, after ZEMAX simulation analysis, the transmittance of the three beam splitters is 25%, 33.33%, and 50% respectively. The fourth side is a reflector. When the millimeter-level laser beam energy passes through the beam splitter, the energy attenuation is stable.

[0034] Specific, efficient grinding-polishing laser composite processing implementation:

[0035] Fix the workpiece on the processing platform 7, install the texture grinding wheel 6 on the spindle 10, start the control cabinet, move the X-axis linear slide 8, the Y-axis stepper motor 9, and the Z-axis stepper motor 16, and rotate the spindle 10. Perform the tool setting process through the industrial camera 5 on the side, so that the rotating grinding wheel texture 6 is close to the pre-processing position on the workpiece surface.

[0036] Fix the laser 13 on the laser support frame 14, and adjust the position so that the laser 13 is in the same plane as the collimator 12. Start the chiller, turn on the laser control cabinet, turn on the red light preview of the laser 13, and adjust the position of the laser so that the infrared light of the laser passes through the internal optical path of the texture grinding wheel 6 in sequence.

[0037] According to the processing requirements, the CNC program is input into the control cabinet, the spindle 10 rotates at the required speed, the protective cover 18 descends to a certain height, safely covers the top of the processing area, the coolant delivery equipment is started, the coolant circulates inside the protective cover, and processing begins.

[0038] The laser 13 is started, and the light beam is introduced into the grinding wheel through the optical path and reaches the first beam splitter 27. Part of the energy is reflected through the first focusing mirror 23 and focused on the same plane of the grinding wheel texture. Part of the energy is transmitted to the second beam splitter 28 and sequentially passes through the third beam splitter 29 and the reflector 30, and is focused on the same plane through the second focusing mirror 24, the third focusing mirror 26, and the fourth focusing mirror 25. During the grinding wheel processing, in-situ laser polishing is realized, and the laser energy emitted from the non-processing position hits the light-absorbing coating inside the protective cover and is absorbed by the protective cover.

[0039] It is to be understood that the present invention is described by some embodiments, and it is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the scope of protection of the present invention.

Claims

1. A laser composite processing device for efficient grinding and polishing of microstructures, including a laser composite precision processing module, a drive module, a safety protection module, a support unit, a connection unit and an observation module. Its characteristics are: The laser composite precision machining module comprises a laser (13), a collimator (12), a spindle (10) and a textured grinding wheel (6); the textured grinding wheel (6) is arranged on the spindle (10), a lens mounting frame (17) is arranged inside the spindle (10), a first beam splitter (27), a second beam splitter (28), a third beam splitter (29) and a reflector (30) are arranged on the lens mounting frame (17) in sequence, a first focusing mirror (23), a second beam splitter (28) and a reflector (30) are arranged on the light splitting path of the first beam splitter (27), and a first focusing mirror (23), a second beam splitter (28) and a reflector (30) are arranged on the light splitting path of the first beam splitter (27). ) is provided with a second focusing mirror (24), a third focusing mirror (26) is provided on the splitting light path of the third beam splitter (29), and a fourth focusing mirror (25) is provided on the reflecting light path of the reflecting mirror (30); the laser beam emitted by the laser (13) passes through the collimator (12) and enters the internal optical cavity of the texture grinding wheel (6), passes through the first beam splitter (27), a part of the energy is transmitted to the lower second beam splitter (28), and a part of the energy is reflected and transmitted through the focusing mirror to form a focus on the same surface of the texture vertex.

2. The laser composite processing device for efficient grinding and polishing of microstructures according to claim 1, Its characteristics are: The support unit comprises a marble gantry (1) and a marble workbench (2); the drive module comprises an X-axis linear slide (8), a Y-axis stepper motor (9), and a Z-axis stepper motor (16); the connection unit comprises a processing platform (7), an adapter plate I (4), a connection plate II (15), a connection plate I (11), a laser support frame (14), and an adapter plate I (20); the observation module comprises a manual slide (3) and an industrial camera (5); and the safety protection module comprises a protective cover (18) and a mounting rod (19).

3. The laser composite processing device for efficient grinding and polishing of microstructures according to claim 1, Its characteristics are: The laser (13) is fixedly mounted on a connecting plate II (15) via a laser support frame (14), and the connecting plate II (15) is mounted on a marble workbench (2).

4. The laser composite processing device for efficient grinding and polishing of microstructures according to claim 1, Its characteristics are: The main shaft (10) is arranged on a connecting plate I (11) via a main shaft fixing frame, and the connecting plate I (11) is connected to a Z-axis stepping motor (16).

5. The laser composite processing device for efficient grinding and polishing of microstructures according to claim 1, Its characteristics are: The X-axis linear slide (8) is arranged on the marble workbench (2), and the Y-axis stepping motor (9) is arranged on the X-axis linear slide (8).

6. The laser composite processing device for efficient grinding and polishing of microstructures according to claim 1, Its characteristics are: The protective cover (18) is provided with a liquid circulation channel inside and is connected to the cooling system.

7. Laser composite processing method for efficient grinding and polishing of microstructures, Its characteristics are: The laser composite processing device for efficient microstructure grinding and polishing according to claim 1 comprises the following steps: Step 1: fix the workpiece on the processing platform (7), install the texture grinding wheel (6) on the main shaft (10), start the control system, move the X-axis linear slide (8), the Y-axis stepping motor (9), and the Z-axis stepping motor (16), rotate the main shaft (10), and perform the tool setting process through the industrial camera (5) of the observation module, so that the rotating texture grinding wheel (6) is close to the pre-processing position on the surface of the workpiece; Step 2: fix the laser (13) on the laser support frame (14), adjust the position so that the laser (13) and the collimator (12) are in the same plane, and perform infrared preview of the laser (13); Step three, inputting the numerical control program, the protective cover (18) descends and covers the processing area, the coolant circulates inside the protective cover (18), the laser (13) is started, the light beam is introduced into the grinding wheel through the optical path, and reaches the first beam splitter (27), part of the energy is reflected through the first focusing mirror (23) and focused on the same plane of the grinding wheel texture (6), part of the energy is transmitted to the second beam splitter (28) and passes through the third beam splitter (29) and the reflecting mirror (30) in sequence, and is focused on the same plane through the second focusing mirror (24), the third focusing mirror (26), and the fourth focusing mirror (25); during the grinding wheel processing, in-situ laser polishing is realized, and the laser energy emitted from the non-processing position hits the light-absorbing coating inside the protective cover and is absorbed by the protective cover.

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