Laser processing device for mirror image processing

Abstract

The utility model discloses a laser processing device for mirror image processing. The device comprises an X-axis moving platform, a Y-axis moving platform, a Z-axis moving platform, a laser source, a scanning galvanometer system, a paraxial vision system, a workpiece table and a control system which are sequentially arranged and located on a base platform. The device is specially designed to be used for mirror image machining, laser galvanometer machining and mirror image machining modes are combined, high-precision synchronous machining of the front face and the back face of a workpiece is achieved, the taper problem occurring in traditional laser machining is effectively solved, and meanwhile the machining quality and efficiency are improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of laser processing, concretely relates to a laser processing device for mirror image processing for improving processing taper. BACKGROUND

[0002] Laser cutting is through the laser of specific wavelength emits high-energy light beam, after the shaping of beam expander, drive galvanometer deflection light beam, and through field lens focus irradiation material surface, utilize light beam deflection scanning to peel off material layer by layer, thereby realize cutting. This process is called galvanometer scanning processing. Another processing mode is that the high-energy light beam emitted by the laser is shaped by the beam expander, and is directly irradiated on the material surface through the objective lens to form a penetrating cutting or scanning cutting.

[0003] The core of the galvanometer processing mode is the application of high-speed galvanometer system and small-aperture telecentric lens. Its advantages include high processing efficiency, small focusing spot and long focal depth, especially suitable for complex processing scenes such as micro-holes and special-shaped holes. However, its disadvantage is that when processing thicker materials (1mm or more), taper problems will occur, and the thicker the material, the more obvious the taper.

[0004] The objective lens processing mode directly irradiates the material surface with the light beam focused by the objective lens for processing. Compared with the galvanometer processing, its advantages are smaller focusing spot, longer focal depth and better beam quality, and there is no taper in the processing process. However, its disadvantage is lower processing efficiency, greater heat influence, and dependence on high-precision linear motor drive, resulting in higher cost.

[0005] With the rapid development of manufacturing industry, designers have higher requirements for the aperture accuracy, taper control, processing depth and surface quality of the processing technology. INVENTION CONTENTS

[0006] In view of the above shortcomings of the prior art, the purpose of the utility model is to provide a laser processing device for mirror image processing, which can solve the problems of poor processing quality and obvious processing taper in the laser processing process.

[0007] The laser processing device for mirror image processing of the utility model is characterized by comprising: a base platform, an X-axis moving platform and a Y-axis moving platform arranged on the base platform, and a Z-axis moving platform installed on the crossbeam above the base platform; a laser source is arranged on the right side of the base platform crossbeam, and a scanning galvanometer system for processing workpieces is connected with the laser source through a mirror system; a side vision system for identifying workpieces is arranged in parallel on the side of the scanning galvanometer system, a workpiece table for placing workpieces is arranged above the X-axis moving platform, the upper surface of the workpiece table is a positioning surface of the workpieces, two positioning pins are arranged on the positioning surface, and positioning holes matched with the two positioning pins are arranged on the front and back surfaces of the workpieces.

[0008] Further, the X-axis moving platform, the Y-axis moving platform, the Z-axis moving platform, the laser source, the scanning galvanometer system and the paraxial vision system are electrically connected with the control system located on the crossbeam.

[0009] Further, the laser source is a pulse laser with a wavelength adjustable range of 355nm to 1064nm, and the outgoing light beam is vertically introduced into the incident end of the scanning galvanometer system after being reflected by the mirror system, and the outgoing end of the scanning galvanometer system acts on the workpiece on the workpiece table.

[0010] Further, the scanning galvanometer system comprises a two-dimensional galvanometer group and a focusing lens, and the deflection angle of the galvanometer is adjusted by the control system to drive the laser beam to move in the two-dimensional plane of the workpiece surface.

[0011] Further, the paraxial vision system comprises a high-resolution CCD camera and a ring-shaped light supplement lamp, the optical axis of the CCD camera is parallel to the laser processing light path, and the CCD camera is used for identifying the 4-Mark positioning point on the workpiece surface and feeding back to the control system.

[0012] Further, the surface of the workpiece table is provided with vacuum adsorption holes, and the vacuum adsorption hole matrix is arranged on the surface of the cuboid block, the cuboid block has a cavity communicating with each vacuum adsorption hole, the cavity is communicated with a vacuum negative pressure device, and the workpiece is fixed on the workpiece table by the vacuum pump adsorption mode.

[0013] Further, the control system comprises a mirror image processing module for generating a center axis symmetric mirror image processing file according to a preset processing drawing, a vision calibration module for realizing automatic alignment of coordinate systems during turning processing in communication with the paraxial vision system, and a motion control module for accurately driving the X / Y / Z-axis moving platform and the scanning galvanometer system to cooperate based on the encoder feedback signal.

[0014] Further, the workpiece is a plate, and the positioning hole penetrates the front surface and the back surface of the workpiece.

[0015] Further, the thickness of the workpiece is 1-2mm plate.

[0016] The working steps of the laser processing device for mirror image processing are as follows:

[0017] The working steps of the laser processing device for mirror image processing are as follows:

[0018] S1: After aligning and positioning the workpiece to be processed (pre-processed positioning hole in batches) with the positioning pin, fixing it on the workpiece table, and calibrating the initial coordinate system through the paraxial vision system;

[0019] S2: Import the processing graph file, and generate the front surface processing path and the 4-Mark positioning point by the control system.

[0020] S3: Start the laser source, control the scanning galvanometer system to complete the front face machining of the workpiece and mark 4-Mark points;

[0021] S4: After generating the center axis symmetry mirror image machining file, turn over the workpiece and fix it, identify the 4-Mark points through the side-axis vision system and establish the turned-over coordinate system;

[0022] S5: Drive the laser beam according to the mirror image machining file to complete the back face machining, realize the symmetry consistency of the front and back face graphics.

[0023] The beneficial effects that can be produced by the present application include: by arranging two positioning pins on the positioning surface, positioning holes matched with the two positioning pins are arranged on the front and back surfaces of the workpiece, thereby facilitating the positioning of the two surfaces of the workpiece, the device has accurate reference when machining the front and back surfaces of the workpiece, the machining shapes of the front and back surfaces of the workpiece are mirror images, and the adjustment of the machining file is also facilitated; by machining the front and back surfaces of the workpiece according to the present application, the problem of single-surface machining taper of the product can be improved, and the machining quality is improved. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is the perspective view of the laser machining device of the present application;

[0025] Figure 2 is the effect view of the workpiece to be machined;

[0026] Figure 3 is the center axis symmetry mirror image machining effect view of the workpiece to be machined;

[0027] Figure 4 is the mirror image machining method flowchart. DETAILED DESCRIPTION

[0028] The present application is further explained and described with reference to specific embodiments and drawings.

[0029] As shown in the drawings, Figure 1 According to the machining mode of the present application, a laser machining device for mirror image machining is provided, which comprises a base platform 10, a multi-axis linear module, a laser source 20, a scanning galvanometer system 30, a side-axis vision system 40, a workpiece table 50 and a control system 60.

[0030] The base platform 10 is integrally made of granite and is used to fix the shaft moving platforms.

[0031] The multi-axis linear module comprises an X-axis moving platform 11 and a Y-axis moving platform 12, which are driven by linear motors, the maximum thrust of the motor is 500N, the repeat positioning accuracy is ±1μm, and the stroke range is 800×600mm; the Z-axis moving platform is controlled by a servo motor in a closed loop and has a vertical stroke of 150mm, which is used to adjust the vertical position of the laser focal point.

[0032] Wherein the laser source module 20 can be an infrared picosecond laser, wavelength 1064nm, pulse width <15ps, peak power >100W, the laser beam is incident to the scanning galvanometer system through the reflection system.

[0033] Wherein the scanning galvanometer system 30 adopts a digital galvanometer, the marking speed is >5000mm / s, including a two-dimensional galvanometer group 31 and a focusing lens 32, controlling the X / Y offset of the laser beam in the plane, the scanning accuracy is ±0.5μm; through the focusing lens, the focal length is 160mm, the effective scanning range is 100×100mm, and the focusing spot diameter is ≤15μm.

[0034] Wherein the paraxial vision system 40 includes a high-resolution CCD camera and a ring-shaped light supplement lamp, the CCD high-resolution camera is matched with the ring-shaped light supplement lamp, the light path of which is parallel to the laser light path, and the distance between the two axes is 15mm.

[0035] The workpiece table 50 is provided with vacuum adsorption holes 51, which are arranged in a matrix on the surface of a cuboid block having a cavity communicating with each vacuum adsorption hole 51, the cavity being in communication with a vacuum negative pressure device, the workpiece is fixed on the workpiece table 50 by vacuum pumping adsorption, the aperture of the vacuum adsorption hole 51 is 0.4mm, the pitch is 8mm×8mm, and the metal / ceramic / glass substrate with a thickness of 0.1-15mm can be adsorbed.

[0036] The upper surface of the workpiece table 50 is a positioning surface of the workpiece, and two positioning pins 70 are arranged on the positioning surface, and positioning holes 80 matched with the two positioning pins are arranged on the front surface and the back surface of the workpiece.

[0037] Wherein the control system 60 includes a mirror image processing module: taking the center axis of the workpiece as the mirror image reference, generating a coordinate system transformation rule (such as original coordinate point (x, y, z)→back surface coordinate point (x', y, z'), x'=W-x); a vision calibration module: through fitting the three-dimensional coordinate offset matrix (Δx, Δy, Δθ) of 4-Mark points, compensating the pose error after the workpiece is turned over; a motion control module: adopting EtherCAT bus synchronous control X / Y / Z axis and galvanometer motion, multi-axis collaborative error <1μm.

[0038] The mirror image processing process based on the device is as follows:

[0039] The element to be processed is installed on the workpiece table 50 and is adsorbed and fixed, a processing file is introduced in the control system 60, and four-corner positioning Mark point processing parameters are automatically generated; the light beam of the laser source 20 is introduced into the scanning galvanometer system 30 through the mirror group 21, four Mark positioning features (the form can be selected as a cross or a circle, the diameter is ≤0.5 mm, and the precision is ±2 μm) are processed around the element, and the feature positions are recorded in real time by the paraxial vision system 40.

[0040] If the processing area exceeds the width of the scanning galvanometer system 30 (≥100×100 mm), the control system 60 divides the figure into several sub-areas, drives the X / Y axis moving platform (11, 12) to perform sub-area displacement compensation, realizes multi-station splicing processing, and stores the processing path and the workpiece thickness data synchronously after completing the front surface cutting / etching of the element.

[0041] The control system 60 calls the mirror image processing module, generates a center axis symmetrical mirror image processing code file (the coordinate transformation formula is x'=W-x, wherein W is the workpiece width) based on the front surface processing track, and associates the vision calibration parameters.

[0042] After the element completing the front surface processing is turned over and is fixed on the workpiece table 50 again, the paraxial vision system 40 is called to perform micron-level positioning calibration (the positioning error is ≤±3 μm) on the four Mark points, the clamping offset is calculated and the mirror image path is dynamically corrected; when the back surface processing area exceeds the width of the galvanometer, the figure is divided according to the mirror image coordinates, and then multi-station processing is performed, and the back surface high-precision symmetrical processing of the workpiece is completed.

[0043] The above only is the preferred embodiment of the present application, and on the premise of not departing from the principle of the present application, a number of improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection range of the present application.

Claims

1. A laser processing apparatus for mirror processing, characterized in that, include: The base platform (10), the X-axis moving platform (11) and the Y-axis moving platform (12) are set on the base platform (10), and the Z-axis moving platform (13) is installed on the crossbeam above the base platform (10); a laser source (20) is provided on the right side of the crossbeam of the base platform (10), and a scanning galvanometer system (30) for processing workpieces is connected to the laser source (20) through a reflector system (21); a paraxial vision system (40) for identifying workpieces is arranged parallel to the side of the scanning galvanometer system (30), and a workpiece stage (50) for placing workpieces is provided above the X-axis moving platform (11). The upper surface of the workpiece stage (50) is the positioning surface of the workpiece, and two positioning pins are provided on the positioning surface. Positioning holes (80) that match the two positioning pins (70) are preset on the front and back surfaces of the workpiece.

2. The laser processing apparatus according to claim 1, characterized in that, The X-axis moving platform (11), Y-axis moving platform (12), Z-axis moving platform (13), laser source (20), scanning galvanometer system (30) and paraxial vision system (40) are electrically connected to the control system (60) located on the crossbeam.

3. The laser processing apparatus according to claim 2, characterized in that, The laser source (20) is a pulsed laser with a wavelength adjustable range of 355nm to 1064nm. Its emitted beam is reflected by the mirror system (21) and then vertically introduced into the incident end of the scanning galvanometer system (30). The output end of the scanning galvanometer system (30) acts on the workpiece on the workpiece stage (50).

4. The laser processing apparatus according to claim 3, characterized in that, The scanning galvanometer system (30) includes a two-dimensional galvanometer group (31) and a focusing lens (32). The galvanometer deflection angle is adjusted by the control system (60) to drive the laser beam to move in a two-dimensional plane on the workpiece surface.

5. The laser processing apparatus according to claim 4, characterized in that, The off-axis vision system (40) includes a high-resolution CCD camera and a ring light. The optical axis of the CCD camera is parallel to the laser processing optical path and is used to identify 4-Mark positioning points on the workpiece surface and feed them back to the control system (60).

6. The laser processing apparatus according to claim 5, characterized in that, The workpiece stage (50) is provided with vacuum adsorption holes (51) on its surface. The vacuum adsorption holes (51) are arranged in a matrix on the surface of a cuboid block. The cuboid block has a cavity that connects each vacuum adsorption hole (51). The cavity is connected to a vacuum negative pressure device. The workpiece is fixed on the workpiece stage (50) by vacuum pump adsorption.

7. The laser processing apparatus according to claim 6, characterized in that, The control system (60) includes: a mirror processing module for generating a central axis symmetrical mirror processing file according to a preset processing drawing; a vision calibration module for automatically aligning the coordinate system during flipping processing by communicating with the off-axis vision system (40); and a motion control module for precisely driving the X / Y / Z axis moving platform and the scanning galvanometer system to coordinate their actions based on encoder feedback signals.

8. The laser processing apparatus according to claim 1, characterized in that, The workpiece is plate-shaped, and the positioning hole penetrates both the front and back of the workpiece.

9. The laser processing apparatus according to claim 1, characterized in that, The thickness of the workpiece is 1-2 mm.

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