Method and system for eliminating processing splicing traces by using random laser ablation points

Abstract

The invention discloses a method for eliminating processing splicing traces by using random laser ablation points, which comprises the following steps of: carrying out layering and blocking treatment on a texture pattern to be processed to obtain a laser processing track required by texture processing; the laser beam is controlled to conduct texture machining and texture splicing on the metal workpiece to be machined according to the laser machining track; and performing ablation treatment on the texture of the metal workpiece subjected to texture splicing by using the random laser ablation points so as to eliminate splicing traces among the blocks and reduce the roughness of the texture of the metal workpiece subjected to ablation. According to the method, splicing traces generated in large-size texture splicing can be eliminated through the random laser ablation points, the workpiece without bad appearance can be obtained, and therefore the roughness of the surface of the metal workpiece is reduced, the product quality is improved, and the requirement of customers for keeping the original color of metal is met.

Description

Technical Field

[0001] The present application relates to the field of laser processing technology, and more specifically, to a method and system for eliminating processing splicing marks by using random laser ablation points. Background Art

[0002] When etching metal surfaces with existing etching technology, laser etching and chemical etching are often used. However, the processing pattern accuracy of chemical etching is often not as good as that of laser etching, and it will cause environmental pollution.

[0003] After the initial laser etching is completed, mechanical sandblasting is often used for further polishing. However, the mechanical sandblasting method is often not fine enough to eliminate the uneven defects caused by the initial laser etching; in addition, the metal surface after mechanical sandblasting is often whitish, which cannot meet the needs of some customers who require the original color of the metal to be maintained. Summary of the invention

[0004] In response to at least one defect or improvement need in the prior art, the present application provides a method and system for eliminating processing splicing marks using random laser ablation points, so as to eliminate the uneven defects caused by the initial laser etching and meet the customer's requirement to maintain the original color of the metal.

[0005] To achieve the above objectives, in a first aspect, the present application provides a method for eliminating machining splicing marks by using random laser ablation points, comprising:

[0006] The texture pattern to be processed is processed in layers and blocks to obtain the laser processing trajectory required for texture processing;

[0007] Controlling the laser beam to perform texture processing and texture splicing on the metal workpiece to be processed according to the laser processing trajectory;

[0008] The texture of the metal workpiece after texture splicing is ablated using random laser ablation points to eliminate the splicing marks between blocks and reduce the roughness of the texture of the metal workpiece after ablation.

[0009] Furthermore, the texture is processed in layers, and each layer of texture pattern to be processed is processed separately in blocks to ensure that the splicing positions between layers are different, so as to reduce the splicing marks.

[0010] Furthermore, the laser beam following the laser processing trajectory is a focused beam formed by the laser generated by the laser passing through a galvanometer and then being focused by a lens.

[0011] Furthermore, the block range of the block processing does not exceed the maximum effective scanning range of the galvanometer.

[0012] Furthermore, the two-dimensional metal workpiece texture pattern is wrapped onto the three-dimensional curved surface, and the obtained data is used to process the three-dimensional metal workpiece texture.

[0013] Furthermore, the splicing of the two-dimensional metal workpiece texture is achieved by a galvanometer in conjunction with a three-axis motor; and the splicing of the three-dimensional metal workpiece texture is achieved by a galvanometer in conjunction with a five-axis motor.

[0014] Furthermore, the galvanometer is fixed on the A-axis of the five-axis machine tool, and the A-axis is fixed on the Z-axis; the metal workpiece is fixed on the C-axis, and the C-axis is fixed on the XY-axis.

[0015] Furthermore, the laser ablation points are randomly distributed within a preset distance range around the laser processing track and the splicing trace, and the dot density can be set.

[0016] In a second aspect, the present application provides a system for eliminating machining splicing marks by using random laser ablation points, comprising:

[0017] a laser supply unit for supplying laser light for setting a texture on a metal workpiece;

[0018] A processing and splicing position coordination unit, which adjusts the relative position between the laser supply unit and the metal workpiece to coordinately implement the texture setting of the metal workpiece;

[0019] A control unit controls the coordination between the laser supply unit and the processing and splicing position coordination unit to implement the method for eliminating processing and splicing marks as described in any one of claims 1-8.

[0020] Furthermore, the laser supply unit comprises:

[0021] A laser, providing a laser beam;

[0022] A beam expander collimator lens, which expands the diameter of the laser beam and maintains the collimation of the beam;

[0023] A galvanometer, controlling the deflection of the laser beam passing through the beam expansion and collimation mirror;

[0024] A lens, which focuses the laser beam passing through the galvanometer to form a focused beam;

[0025] The processing and splicing position coordination unit is a five-axis machine tool, which fixes the galvanometer on the A axis, which is fixed on the Z axis; and fixes the metal workpiece on the C axis, which is fixed on the XY axis.

[0026] In general, the above technical solutions conceived by the present application can achieve the following beneficial effects compared with the prior art:

[0027] (1) The present application utilizes random laser ablation points to eliminate the splicing marks produced in the splicing of large-size textures, and can obtain a workpiece without a bad appearance, thereby reducing the roughness of the metal workpiece surface, improving product quality, and meeting the customer's demand for maintaining the original color of the metal.

[0028] (2) The present application processes each layer of texture pattern that needs to be processed separately, ensuring that the splicing positions between layers are different, thereby reducing the splicing marks. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 A core flow chart of a method for eliminating machining splicing marks by using random laser ablation points provided in an embodiment of the present application;

[0031] Figure 2 The overall structure diagram of the five-axis machine tool provided in the embodiment of the present application;

[0032] Figure 3 A schematic diagram of the structure of a system for eliminating machining splicing marks by using random laser ablation points provided in an embodiment of the present application;

[0033] Figure 4 This is a diagram of the arrangement of the hexagonal texture pattern provided in the embodiment of the present application;

[0034] Figure 5 A schematic diagram of the intelligent layering and block division of software provided in the embodiment of the present application;

[0035] Figure 6 A schematic diagram of random laser ablation dotting to eliminate splicing marks provided in an embodiment of the present application;

[0036] Reference numerals:

[0037] 1-Laser;

[0038] 2- beam expansion collimator;

[0039] 3- Galvanometer;

[0040] 4- Lens;

[0041] 5- Focus the laser beam;

[0042] 6-Metal workpieces;

[0043] 7-C-axis rotary motor;

[0044] 8-XY axis servo motor;

[0045] 9-Z-axis servo motor;

[0046] 10-A axis rotating motor;

[0047] 11- Control system;

[0048] 12-Splicing traces;

[0049] 13-Laser processing trajectory;

[0050] 14- Random laser ablation spots. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. In addition, the technical features involved in each embodiment of the present application described below can be combined with each other as long as they do not conflict with each other.

[0052] The terms "first", "second" or "nth" in the specification, claims or drawings of the present application are used to distinguish different objects rather than to describe a specific order. In addition, the terms "including" or "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device including a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units inherent to these processes, methods, products or devices.

[0053] Background Technology Introduction

[0054] 1. Five-axis machine tools, five-axis processing, etc.

[0055] Five-axis machining (5Axis Machining) is a mode of CNC machine tool processing. According to ISO regulations, when describing the movement of CNC machine tools, a right-hand rectangular coordinate system is used; the coordinate axis parallel to the main axis is defined as the Z axis, and the rotation coordinates around the X, Y, and Z axes are A, B, and C respectively. The movement of each coordinate axis can be achieved by the workbench or the movement of the tool, but the direction is defined by the movement direction of the tool relative to the workpiece. Usually, five-axis linkage refers to the linear interpolation movement of any five coordinates of X, Y, Z, A, B, and C.

[0056] In other words, five axes refers to three moving axes (linear axes) X, Y, and Z plus any two rotating axes. Compared with the common three-axis (three degrees of freedom X, Y, and Z) machining, five-axis machining refers to machining parts with complex geometric shapes, which requires the machining tool to be able to position and connect in five degrees of freedom. The machine tools used for five-axis machining are usually called five-axis machine tools or five-axis machining centers.

[0057] 2. Working principle of five-axis machining center

[0058] The working principle of the five-axis machining center is mainly based on the linkage control of its five independent axes, which include three linear axes (X, Y, Z) and two rotary axes (A, B or C). The following is a detailed explanation of the working principle of the five-axis machining center.

[0059] Linkage control of five independent axes: The core of the five-axis machining center is the ability to achieve linkage control of five axes. The X-axis, Y-axis, and Z-axis represent the movement of the workpiece in the front and back, left and right, and up and down directions, respectively, and are used to control the position of the workpiece in the plane and three-dimensional space. The A-axis and C-axis (or B-axis) are used to control the rotation of the workpiece. The A-axis rotates around the X-axis, and the C-axis rotates around the Z-axis (the B-axis rotates around the Y-axis), which can achieve rotation processing in different directions. This multi-axis linkage capability enables the five-axis machining center to perform all-round processing of the workpiece in three-dimensional space, greatly improving the accuracy and efficiency of processing.

[0060] 3. XYZ coordinate axis and ABC coordinate axis of five-axis machine tool

[0061] The XYZ coordinate axes of a five-axis machine tool refer to the three linear moving axes of the machine tool in space.

[0062] Specifically:

[0063] X-axis: This is a horizontal axis on a five-axis machine, usually used to move a workpiece or tool along the length of the machine. The range of the X-axis determines the length of the workpiece that the five-axis machine can handle.

[0064] Y-axis: The Y-axis is another horizontal moving axis perpendicular to the X-axis. It is used to move the workpiece or tool along the width direction of the five-axis machine tool. The moving range of the Y-axis determines the width of the workpiece that the machine tool can handle.

[0065] Z-axis: The Z-axis is a vertical moving axis perpendicular to the X-axis and Y-axis. It is used to move the workpiece or tool along the height direction of the five-axis machine tool. The moving range of the Z-axis determines the height of the workpiece that the machine tool can handle and the cutting depth of the tool.

[0066] In addition to the three linear motion axes mentioned above, the five-axis machine tool also includes two rotation axes:

[0067] A-axis: Usually an axis that rotates around the X-axis, also called a swing head. It allows the tool or workpiece to rotate in the X-axis direction, thereby achieving processing of the side or complex curved surface of the workpiece.

[0068] C-axis: An axis that rotates around the Z-axis, also known as the table rotation axis. It allows the workpiece to rotate in a horizontal plane, thereby achieving processing of the workpiece's circumferential surface or complex curved surface.

[0069] As described in the background technology section of the specification, after the initial laser etching is completed, mechanical sandblasting is often used for further polishing. However, the mechanical sandblasting method is often not fine enough to eliminate the uneven defects caused by the initial laser etching; in addition, the metal surface after mechanical sandblasting is often whitish, which cannot meet the needs of some customers to maintain the original color of the metal. In view of this, the present application provides a method and system for eliminating processing splicing marks using random laser ablation points, which aims to overcome the technical defects of large-scale two-dimensional or three-dimensional metal workpiece surface texture splicing processing splicing marks, large surface roughness, and meet the needs of customers to maintain the original color of the metal.

[0070] refer to Figure 1-Figure 6 An embodiment of the present application provides a method for eliminating processing splicing marks by using random laser ablation points, which may specifically include the following steps.

[0071] Step 1: The texture pattern to be processed is processed in layers and blocks to obtain the laser processing trajectory required for texture processing.

[0072] In some embodiments, specifically, the control system 11 controls a large-size texture pattern (for example, a hexagonal texture pattern, see Figure 4 ) for intelligent block and layer processing, a total of 60 layers, each layer processing depth is 1-5μm, each layer of 60 layers has different block boundaries, refer to Figure 5 , in order to calculate the processing trajectory 13 required for all texture processing.

[0073] The block range cannot exceed the maximum effective scanning range of the galvanometer 3, and the maximum effective scanning range of the galvanometer 3 is 50mm*50mm.

[0074] Step 2: Control the laser beam to perform texture processing and texture splicing on the metal workpiece 6 to be processed according to the laser processing trajectory 13 generated in step 1.

[0075] In some embodiments, the metal workpiece 6 is a stainless steel plate with a length of 400 mm, a width of 400 mm, a thickness of 2 mm, and a hexagonal texture pattern arrangement as shown in FIG. Figure 4As shown. A laser 1 with a pulse width ranging from nanoseconds to femtoseconds is used. The laser beam is a focused laser beam 5 formed by the laser generated by the laser 1 passing through a galvanometer 3 and then focused by a lens 4. More specifically, a 50W infrared pulsed laser 1 is used, and the laser pulse passes through a beam expander collimator 2 and is focused by a lens 4 to obtain a focused laser beam 5.

[0076] Appropriate laser ablation parameters are set, with a power of 25 W and a frequency of 50 kHz. The control system 11 drives the focused laser beam 5 to deflect by controlling the galvanometer 3 . The metal workpiece 6 can be subjected to block texture processing according to the laser processing trajectory 13 obtained in step 1 to form a block texture.

[0077] The metal texture depth does not exceed 0.5mm, the metal texture size does not exceed 1200mm, the laser ablation depth is between 1-5μm, the texture needs to be processed in layers, and the number of layers = texture depth / single ablation depth.

[0078] For each layer of texture pattern to be processed, separate blocks are processed to ensure that the joint positions between layers are different, so as to reduce the joint marks. Figure 5 (a) Processing the first layer of texture pattern, the blocks are divided according to the block boundaries a1, a2, a3, and a4.

[0079] After the first layer is processed, Figure 5 (b) Processing the second layer of texture pattern, the blocks are divided according to the block dividing lines b1, b2, b3, and b4.

[0080] …

[0081] After the 58th layer is processed, Figure 5 (c) Processing the 59th layer texture pattern, the blocks are divided according to the block boundaries c1, c2, c3, and c4.

[0082] according to Figure 5 (d) The last layer, i.e., the 60th layer of texture pattern, is processed and divided into blocks according to the block dividing lines d1, d2, d3, and d4.

[0083] At this point, the texture ablation of the metal workpiece 6 is completed.

[0084] The galvanometer 3 drives the focused laser beam 5 to deflect, and at the same time cooperates with the axis movement to complete the splicing of different block textures, so as to realize the laser ablation of large-scale metal surface textures. The galvanometer 3 is fixed on the A axis of the five-axis machine tool, and the A axis is fixed on the Z axis. The metal workpiece 6 is fixed on the C axis, and the C axis is fixed on the XY axis.

[0085] The focus of the focused laser beam 5 is controlled by the Z-axis servo motor 9; the splicing processing of the two-dimensional metal workpiece texture is completed by the galvanometer 3, the XY-axis servo motor 8 and the Z-axis servo motor 9; the splicing processing of the three-dimensional metal workpiece texture is completed by the galvanometer 3, the XY-axis servo motor 8, the Z-axis servo motor 9, the C-axis rotation motor 7 and the A-axis rotation motor 10; the tangent angle between the focused laser beam 5 and the block surface is 90°±20°.

[0086] The three-dimensional metal workpiece texture requires the two-dimensional metal workpiece texture graphics to be covered onto the three-dimensional surface through the equipment software, and the obtained data is used to process the three-dimensional metal workpiece texture, which can effectively prevent the graphic distortion caused by direct projection processing.

[0087] Step 3: Use random laser ablation points to ablate the texture of the metal workpiece after texture splicing to eliminate splicing marks between blocks and reduce the roughness of the texture of the metal workpiece after ablation.

[0088] After the large-size texture pattern splicing process is completed, the surface of the metal workpiece 6 is processed by random laser ablation points 14 to obtain the final metal texture sample. In some embodiments, specifically, appropriate laser dotting parameters are set, power 12.5W, frequency 50kHz, dotting time 0.1ms, and dot density dpi=1000. Figure 6 The laser dots are randomly distributed within a certain range around the laser processing track 13 and the splicing mark 12 generated in step 1, and the dot density can be set by the device software. The number of random laser dots can be one or more times. The laser dot effect is jointly determined by three parameters: laser power, frequency and dot time, and can be controlled by the device software.

[0089] After setting the appropriate laser dot parameters, the surface of the metal sample 6 can be processed using random laser ablation points 14 to eliminate the splicing marks 12 formed by splicing. Because the random laser ablation points are smaller than the sand of traditional mechanical sandblasting, the texture of the metal workpiece after being processed by the laser ablation points will be more delicate. The metal surface after mechanical sandblasting is whitish, and some customers have the demand to maintain the original color of the metal. At this time, the random laser ablation points can maintain the original color of the metal when dotting, which just meets the demand to maintain the original color of the metal. The use of random laser ablation points to polish the metal texture solves the problem of splicing marks that are easily visible to the naked eye during the splicing of large-size metal textures, optimizes the appearance of the metal workpiece, reduces the roughness of the metal texture surface, and improves product quality.

[0090] refer to Figure 2 and Figure 3 Another embodiment of the present application proposes a system that utilizes random laser ablation points to eliminate processing and splicing marks. The system may specifically include the following components.

[0091] The laser supply unit provides laser for setting texture on the metal workpiece. Specifically, the laser supply unit can be a component that provides a focused laser beam 5, which can be composed of multiple components.

[0092] The processing and splicing position coordination unit adjusts the relative position between the laser supply unit and the metal workpiece to coordinate and realize the texture setting of the metal workpiece.

[0093] The control unit controls the coordination between the laser supply unit and the processing and splicing position coordination unit to realize the aforementioned method for eliminating processing and splicing marks.

[0094] Further, the laser supply unit may include:

[0095] The laser 1 provides a laser beam.

[0096] The beam expander collimator 2 expands the diameter of the laser beam and maintains the collimation of the beam.

[0097] The galvanometer mirror 3 controls the deflection of the laser beam passing through the beam expander collimator lens 2 .

[0098] The lens 4 focuses the laser beam passing through the galvanometer mirror 3 to form a focused beam.

[0099] The processing and splicing position coordination unit is a five-axis machine tool, which fixes the galvanometer 3 on the A axis of the five-axis machine tool, and fixes the A axis on the Z axis; fixes the metal workpiece 6 on the C axis, and fixes the C axis on the XY axis.

[0100] The processing and splicing position coordination unit also includes a C-axis rotary motor 7, an XY-axis servo motor 8, a Z-axis servo motor 9, and an A-axis rotary motor 10. The focus of the focused laser beam 5 is controlled by the Z-axis servo motor 9; the splicing processing of the two-dimensional metal workpiece texture is completed by the galvanometer 3, the XY-axis servo motor 8, and the Z-axis servo motor 9, and the splicing processing of the three-dimensional metal workpiece texture is completed by the galvanometer 3, the XY-axis servo motor 8, the Z-axis servo motor 9, the C-axis rotary motor 7, and the A-axis rotary motor 10.

[0101] The specific technical details in the embodiment of the system for eliminating processing splicing marks by using random laser ablation points can be referred to the aforementioned embodiment of the method for eliminating processing splicing marks by using random laser ablation points, and will not be repeated here.

[0102] Those skilled in the art will appreciate that the technical features described in the various embodiments and / or claims of the present application may be combined and / or coupled in a variety of ways, even if such combinations and / or couplings are not explicitly described in the present application. In particular, without departing from the spirit and teachings of the present application, the technical features described in the various embodiments and / or claims of the present application may be combined and / or coupled in a variety of ways, and all of these combinations and / or couplings fall within the scope of the present application.

[0103] Although the present application has been shown and described with reference to specific exemplary embodiments of the present application, it should be understood by those skilled in the art that various changes in form and details may be made to the present application without departing from the spirit and scope of the present application as defined by the appended claims and their equivalents. Therefore, the scope of the present application should not be limited to the above-mentioned embodiments, but should be determined not only by the appended claims, but also by the equivalents of the appended claims.

Claims

1. A method for eliminating machining splicing marks by using random laser ablation points, characterized in that: include: The texture pattern to be processed is processed in layers and blocks to obtain the laser processing trajectory required for texture processing; Controlling the laser beam to perform texture processing and texture splicing on the metal workpiece to be processed according to the laser processing trajectory; The texture of the metal workpiece after texture splicing is ablated using random laser ablation points to eliminate the splicing marks between blocks and reduce the roughness of the texture of the metal workpiece after ablation.

2. The method for eliminating processing and splicing marks according to claim 1, characterized in that: The texture is processed in layers, and each layer of texture pattern that needs to be processed is processed separately in blocks to ensure that the splicing positions between layers are different, so as to reduce the splicing marks.

3. The method for eliminating processing and splicing marks according to claim 1, characterized in that: The laser beam following the laser processing track is a focused beam formed by the laser generated by the laser passing through the galvanometer and then being focused by the lens.

4. The method for eliminating processing and splicing marks according to claim 3, characterized in that: The block range of the block processing does not exceed the maximum effective scanning range of the galvanometer.

5. The method for eliminating processing and splicing marks according to claim 1, characterized in that: The two-dimensional metal workpiece texture graphics are wrapped onto the three-dimensional surface, and the obtained data is used to process the three-dimensional metal workpiece texture.

6. The method for eliminating processing and splicing marks according to claim 5, characterized in that: The splicing of the two-dimensional metal workpiece texture is achieved by a galvanometer in conjunction with a three-axis motor; the splicing of the three-dimensional metal workpiece texture is achieved by a galvanometer in conjunction with a five-axis motor.

7. The method for eliminating processing and splicing marks according to claim 6, characterized in that: The galvanometer is fixed on the A axis of the five-axis machine tool, and the A axis is fixed on the Z axis; the metal workpiece is fixed on the C axis, and the C axis is fixed on the XY axis.

8. The method for eliminating processing and splicing marks according to claim 1, characterized in that: The laser ablation points are randomly distributed within a preset distance range around the laser processing track and the splicing trace, and the dot density can be set.

9. A system for eliminating machining splicing marks using random laser ablation points, characterized in that: include: a laser supply unit for supplying laser light for setting a texture on a metal workpiece; A processing and splicing position coordination unit, which adjusts the relative position between the laser supply unit and the metal workpiece to coordinately implement the texture setting of the metal workpiece; A control unit controls the coordination between the laser supply unit and the processing and splicing position coordination unit to implement the method for eliminating processing and splicing marks as described in any one of claims 1-8.

10. The system for eliminating processing and splicing marks according to claim 9, characterized in that: The laser supply unit comprises: A laser, providing a laser beam; A beam expander collimator lens, which expands the diameter of the laser beam and maintains the collimation of the beam; A galvanometer, controlling the deflection of the laser beam passing through the beam expansion and collimation mirror; A lens, which focuses the laser beam passing through the galvanometer to form a focused beam; The processing and splicing position coordination unit is a five-axis machine tool, which fixes the galvanometer on the A axis, which is fixed on the Z axis; and fixes the metal workpiece on the C axis, which is fixed on the XY axis.

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