A laser processing device for low-speed diesel engine crosshead pin surface micro-texture and a control method thereof

Abstract

This invention relates to a laser processing apparatus and its control method for microtexturing the surface of a crosshead pin in a low-speed diesel engine. The laser processing apparatus is used to form several pits on the surface of the crosshead pin, and includes a laser emitting mechanism; a beam processing mechanism for refracting the laser emitted by the laser emitting mechanism so that the laser acts on the crosshead pin; a workpiece clamping module for fixing and rotating the crosshead pin; and a drive mechanism for moving the laser emitting mechanism so that the laser beam emitted by the laser emitting mechanism can uniformly irradiate the beam processing mechanism. In this invention, the coverage area of ​​the beam processing mechanism can be adjusted according to actual needs. After processing one coverage area, the workpiece only needs to be rotated to the next angle. A maximum of 360 rotations are required to complete the processing of the entire crosshead pin, far fewer than the millions of movements required by traditional single-point processing, increasing efficiency by tens to hundreds of times.

Description

Technical Field

[0001] This invention belongs to the field of laser processing technology, specifically relating to a laser processing device and its control method for microtexturing the surface of a crosshead pin in a low-speed diesel engine. Background Technology

[0002] Low-speed diesel engines are the main propulsion power unit for large ships. The crosshead pin is the core load-bearing component connecting the piston rod and the crosshead slide block, and it bears huge alternating loads and sliding friction during operation. In recent years, the processing of micron-level pit arrays (i.e., microtextures) on the surface of the crosshead pin has become a key technology to improve the lubrication condition and reduce friction and wear.

[0003] Laser surface microtexturing technology is widely used in such processing due to its advantages of non-contact operation, high precision, and small heat-affected zone. However, the crosshead pin has a large surface area, and the number of micropits required typically reaches hundreds of thousands or even millions. If the traditional single-point pulse-by-pulse processing method is used, the switching time for a single laser beam to move from creating one pit to the next is much longer than the effective light output time. Processing millions of micropits can take up to several hours, which cannot meet the batch production cycle. Even if a beam splitting module is used to divide a single laser beam into a 4×4 or 8×8 array for parallel processing, although multiple micropits can be formed in one pass, the energy of the single beam decreases after splitting, often requiring multiple pulses to accumulate into pits, resulting in limited actual efficiency improvement. At the same time, it also brings problems such as edge micropit deformation and uneven energy distribution.

[0004] Therefore, there is an urgent need for a dedicated laser processing device that can balance high efficiency and high quality, enabling rapid and uniform processing of large-area microtextures on highly curved cylindrical surfaces. Summary of the Invention

[0005] The purpose of this invention is to provide a laser processing device and its control method for microtexturing the surface of a crosshead pin in a low-speed diesel engine in order to solve the problems mentioned in the background art.

[0006] The present invention achieves the above objectives through the following technical solutions: A laser processing apparatus for microtexturing the surface of a crosshead pin in a low-speed diesel engine, used to form several pits on the surface of the crosshead pin, including: Laser emitting mechanism; The beam processing mechanism is used to refract the laser generated by the laser emitting mechanism so that the laser acts on the crosshead pin; The workpiece clamping module is used to fix and rotate the crosshead pin; and The drive mechanism is used to move the laser emitting mechanism so that the laser beam emitted by the laser emitting mechanism can be evenly irradiated onto the beam processing mechanism.

[0007] Preferably, the laser emitting mechanism includes a mounting plate and a laser disposed on the mounting plate. The mounting plate is fixedly mounted on a dedicated laser micro-weaving machine tool, and the laser is located directly above the crosshead pin and at the midpoint of the workpiece. The laser is a nanosecond pulsed fiber laser.

[0008] Preferably, the drive mechanism includes a reducer fixedly mounted on the mounting plate, a drive motor connected to the reducer, a connector for connecting the laser and the mounting plate, and a first telescopic member mounted on the connector; The connecting component is a ball joint, and the first telescopic component is used to drive the laser and the mounting plate to rotate.

[0009] Preferably, the drive mechanism includes two telescopic components fixedly mounted on the mounting plate; The laser and the mounting plate are connected by a ball joint, allowing the laser emitting end of the laser to swing freely relative to the mounting plate.

[0010] Preferably, the laser surface is provided with an iron protective layer; Both of the telescopic ends of the second telescopic component are fixedly equipped with magnetic components for adsorbing the protective layer.

[0011] Preferably, the beam processing mechanism includes an arc-shaped plate with several through holes and a refractive element disposed in the through holes, wherein the refractive element is a mirror or a prism.

[0012] Preferably, two No. 3 telescopic components are fixedly provided on the mounting plate. The two No. 3 telescopic components are respectively located at both ends of the arc-shaped plate. An arc-shaped strip is fixedly provided at the telescopic end of the No. 3 telescopic component. The arc-shaped strip is in contact with the surface of the arc-shaped plate and is used to drive the arc-shaped plate to deform in order to adapt to different crosshead pins.

[0013] Preferably, two brackets are fixedly provided on the mounting plate, and the two brackets are respectively located at the bottom of both ends of the arc-shaped plate; The two telescopic components No. 3 are respectively fixedly installed on the corresponding brackets, and the telescopic direction of the telescopic components No. 3 is vertical. The arc-shaped strip is fixedly connected to the surface of the arc-shaped plate.

[0014] A method for controlling the laser processing of micro-textured surfaces on crosshead pins of low-speed diesel engines includes the following steps: S1: Install the crosshead pin onto the workpiece clamping module and automatically align the cylindrical axis; S2: The drive mechanism moves the laser emitting mechanism and the beam processing mechanism above the workpiece. The drive mechanism moves the laser beam on the beam processing mechanism. Laser beams at different irradiation angles are refracted or reflected by the beam processing mechanism and then vertically irradiate the workpiece surface, completing the micro-texture processing of the area covered by the beam processing mechanism. S3: The workpiece clamping module drives the workpiece to rotate, moving the unprocessed area below the beam processing mechanism. Repeat step three until the surface treatment of the entire workpiece is completed.

[0015] The beneficial effects of this invention are as follows: 1. The coverage area of ​​the beam processing mechanism in this invention can be adjusted according to actual needs. After processing one coverage area, the workpiece only needs to be rotated to the next angle. The entire crosshead pin can be processed by rotating a maximum of 360 times around the circumference, which is far less than the millions of movements required by traditional single-point processing, and the efficiency is increased by tens to hundreds of times.

[0016] 2. This invention precisely controls the movement path of the laser beam on the beam processing mechanism through a drive mechanism, so that laser beams at different irradiation angles can be processed to irradiate the workpiece surface perpendicularly, effectively eliminating the problems of spot distortion and energy unevenness caused by the cylindrical curvature, and ensuring that the depth and roundness of the micro-pits in each area are consistent.

[0017] 3. The deformable arc plate structure of the present invention drives the arc strip through the second telescopic component to change the radius of curvature of the arc plate, which can quickly adapt to crosshead pins of different diameters without replacing hardware, thus significantly improving the versatility of the equipment. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention; Figure 2 This is a schematic diagram illustrating the working principle of the present invention; Figure 3 This is the right view of the present invention; Figure 4 This is a schematic diagram of the structure of Embodiment 2 of the present invention; Figure 5 This is an exploded view of the present invention.

[0019] In the diagram: 1. Mounting plate; 2. Laser; 3. Reducer; 4. Drive motor; 5. Telescopic component No. 1; 6. Ball hinge; 7. Telescopic component No. 2; 8. Magnetic component; 9. Through hole; 10. Curved plate; 11. Refractive component; 12. Telescopic component No. 3; 13. Curved strip; 14. Bracket. Detailed Implementation

[0020] The present application will now be described in further detail. It should be noted that the following specific embodiments are only used to further illustrate the present application and should not be construed as limiting the scope of protection of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content.

[0021] Example 1

[0022] like Figure 1-3 As shown, a laser processing device for microtexturing the surface of a crosshead pin in a low-speed diesel engine is used to form several pits on the surface of the crosshead pin. The device includes a laser emitting mechanism, a drive mechanism for moving the laser emitting mechanism, and a beam processing mechanism. The beam processing mechanism is used to refract the laser generated by the laser emitting mechanism so that the laser acts on the crosshead pin.

[0023] In this embodiment, the processing device also includes a workpiece clamping module, an online monitoring and feedback control module, an auxiliary process module, and safety protection and a machine frame.

[0024] The workpiece clamping module features a head and tailstock configuration, utilizing a dedicated laser micro-texturing machine tool. One end is a servo-driven chuck, and the other end is a pneumatic movable center. After the workpiece is loaded, it can automatically align with the cylindrical axis. A central frame provides intermediate auxiliary support to reduce deflection deformation of long workpieces.

[0025] Before machining, the online monitoring and feedback control module uses a line laser profilometer to scan the actual generatrix and radial runout of the workpiece after clamping, generating a surface model to compensate for the machining trajectory. During machining, the micro-textured structure is observed in real time. After machining, the depth and diameter of micro-pits in key areas are randomly checked; if the dimensions exceed tolerances, a correction command or alarm is issued.

[0026] The auxiliary process module uses coaxial or off-axis nozzles to purge compressed air or nitrogen (flow rate 10-50 L / min) to remove plasma and residue, preventing the recast layer from being too thick; it uses a high negative pressure industrial dust collector connected to a sealed protective cover in the processing area to maintain cleanliness; and it provides constant temperature (25±1℃) cooling water for laser 2, scanning head, turntable motor, etc.

[0027] Safety protection and the entire machine frame include a fully enclosed protective cover: laser leakage prevention (OD6+ level), with a safety interlock door, and the observation window uses laser protective glass.

[0028] It should be noted that after the workpiece is clamped, the drive mechanism moves the laser emitting mechanism and the beam processing mechanism above the workpiece, establishing a coordinate system with the dedicated laser micro-texturing machine as a reference. The drive mechanism moves the laser emitting mechanism, allowing the laser to move along the beam processing mechanism. Laser beams at different irradiation angles, after being processed by the beam processing mechanism, are perpendicularly irradiated onto the workpiece surface, quickly completing the surface micro-texturing treatment of the area covered by the beam processing mechanism. After completing the surface micro-texturing treatment of this area, the dedicated laser micro-texturing machine rotates the workpiece, moving the unprocessed portion below the beam processing mechanism. After several rotations of the workpiece, the surface treatment of the entire workpiece is completed.

[0029] Traditional processing methods involve single-point processing (or using a beam splitter to divide a single laser beam into a 4×4 or 8×8 array, forming multiple micro-pits in a single scan). Assuming 1 million micro-pits need to be processed on a workpiece, it takes 1 microsecond (physical time) for a single laser beam to create one pit, and 100 microseconds to move to the next pit (the time consumed by switching processing stations often far exceeds the effective processing time of the laser beam). In single-point processing mode, the workpiece or laser emitting mechanism needs to move 1 million times. This invention enables the laser emitting mechanism to instantly complete the workpiece surface treatment within the coverage area of ​​the beam processing mechanism. The coverage area of ​​the beam processing mechanism can be adjusted according to actual needs, but is at least 1 / 360th of the workpiece surface area (taking the workpiece's circumference as an example). Based on this, this invention requires at most 360 movements, improving processing efficiency several times over compared to traditional methods.

[0030] In this embodiment, the laser emitting mechanism includes a mounting plate 1 and a laser 2 mounted on the mounting plate 1. The mounting plate 1 is fixedly mounted on a dedicated laser micro-weaving machine tool, such that the laser 2 is located directly above the workpiece and at the midpoint of the workpiece.

[0031] Preferably, the laser 2 is a nanosecond pulsed fiber laser, which can efficiently ablate and form textures such as micro-pits and micro-grooves, with a small heat-affected zone and high cost performance.

[0032] Preferably, the drive mechanism in this embodiment includes a reducer 3 fixedly mounted on the mounting plate 1, a drive motor 4 connected to the reducer 3, a connector for connecting the laser 2 and the mounting plate 1, and a first telescopic member 5 (which may be an electric push rod, the same below) mounted on the connector.

[0033] Among them, the connecting part adopts ball hinge 6, and the first telescopic part 5 is used to drive the laser 2 and the mounting plate 1 to rotate.

[0034] It should be noted that the working principle of the drive mechanism is as follows: the drive motor 4 drives the laser 2 to rotate through the reducer 3, and at the same time, the first telescopic component 5 drives the laser 2 to rotate relative to the mounting plate 1, causing the laser beam generated by the laser 2 to change angle from vertical downward until it reaches the edge of the beam processing mechanism. As the laser beam rotates around the connecting component, it can cover the beam processing mechanism below. The beam processing mechanism refracts the laser beam, so that the laser beam can vertically irradiate the workpiece, thereby forming several micro-pits on the workpiece.

[0035] Laser 2 and telescopic component 5 are powered by a rotating ring, which eliminates the problem of wire tangling.

[0036] In this embodiment, the beam processing mechanism includes an arc-shaped plate 10 with a plurality of through holes 9 and a refractive element 11 disposed in the through holes 9. The refractive element 11 is a mirror or a prism.

[0037] The laser beam is deflected by the refraction of the refractive element 11, which can adjust the irradiation angle of the laser beam so that the laser beam irradiates the workpiece surface perpendicularly, ensuring the processing effect of the micro-pits.

[0038] Example 2

[0039] like Figure 4-5 As shown, unlike Embodiment 1, the drive mechanism includes two telescopic members 7 fixedly mounted on the mounting plate 1.

[0040] Laser 2 is ball-jointed to mounting plate 1. The lower end of laser 2 is the laser beam emitting end, which can swing freely relative to mounting plate 1.

[0041] It should be noted that the working principle of the drive mechanism is as follows: the two telescopic components 7 are located on both sides of the laser 2, and the telescopic directions of the two telescopic components 7 are perpendicular to each other. Under the control of the PLC, the telescopic ends of the two telescopic components 7 extend autonomously, enabling the laser beam to move freely on the beam processing mechanism. When the laser beam irradiates the beam processing mechanism, it is refracted or reflected, allowing the laser beam to irradiate the workpiece surface perpendicularly, thereby forming micro-dimples.

[0042] Preferably, the surface of the laser 2 is provided with an iron protective layer.

[0043] Both telescopic ends of the two No. 2 telescopic components 7 are fixedly equipped with magnetic components 8 for adsorbing the protective layer. The magnetic components 8 are permanent magnets.

[0044] It should be noted that by setting up the magnetic component 8, when the magnetic component 8 comes into contact with the protective layer, it will be attracted to the protective layer. When the two telescopic components 7 extend and retract, they will drive the protective layer and the laser 2 to move rapidly, preventing the laser 2 from moving lagging or displacing, thus ensuring processing efficiency.

[0045] Furthermore, the magnetic component 8 is spherical.

[0046] Example 3

[0047] Based on Embodiment 1, in this embodiment, two No. 3 telescopic components 12 are fixedly provided on the mounting plate 1. The two No. 3 telescopic components 12 are located at both ends of the arc plate 10. An arc strip 13 is fixedly provided at the telescopic end of the No. 3 telescopic component 12. The arc strip 13 is in contact with the surface of the arc plate 10 and is used to drive the arc plate 10 to deform in order to adapt to different crosshead pins.

[0048] It should be noted that, in order to accommodate workpieces of different sizes, especially those with different diameters, two brackets 14 are fixedly installed on the mounting plate 1. The two brackets 14 are located at the bottom of both ends of the arc-shaped plate 10. Two telescopic components 12 are fixedly installed on the brackets 14 respectively, and the telescopic direction of the telescopic components 12 is vertical.

[0049] The arc-shaped strip 13 is attached to the surface of the arc-shaped plate 10 and is fixedly connected. When the diameter of the workpiece changes, the telescopic end of the third telescopic component 12 extends, and the telescopic end drives the arc-shaped strip 13 to move downward, so that both ends of the arc-shaped strip 13 contact the bracket 14. Under the obstruction of the bracket 14, the arc-shaped strip 13 deforms, and the radius of curvature of both the arc-shaped strip 13 and the arc-shaped plate 10 increases, which can be used for workpieces with larger diameters.

[0050] Conversely, the telescopic end of the third telescopic component 12 shortens, and the arc-shaped strip 13 moves upward. A stop block can be added to the bracket 14 to block both ends of the arc-shaped strip 13, thereby reducing the radius of curvature of the arc-shaped strip 13 and making it suitable for workpieces with smaller diameter values.

[0051] To ensure the normal deformation of the arc plate 10, a metal strip can be attached to the surface of the arc plate 10. The metal strip is parallel to the axis of the arc plate 10, which can make the radius of curvature of the arc plate 10 change uniformly and prevent the axis from bending easily.

[0052] Example 4

[0053] A control method for a laser processing device for micro-texturing the surface of a crosshead pin in a low-speed diesel engine includes the following steps: S1: Install the crosshead pin onto the workpiece clamping module and automatically align the cylindrical axis; S2: The drive mechanism moves the laser emitting mechanism and the beam processing mechanism above the workpiece. The drive mechanism moves the laser beam on the beam processing mechanism. Laser beams at different irradiation angles are refracted or reflected by the beam processing mechanism and then vertically irradiate the workpiece surface, completing the micro-texture processing of the area covered by the beam processing mechanism. S3: The workpiece clamping module drives the workpiece to rotate, moving the unprocessed area below the beam processing mechanism. Repeat step three until the surface treatment of the entire workpiece is completed.

[0054] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A laser processing device for microtexturing the surface of a crosshead pin in a low-speed diesel engine, used to form several pits on the surface of the crosshead pin, characterized in that, include: Laser emitting mechanism; The beam processing mechanism is used to refract the laser generated by the laser emitting mechanism so that the laser acts on the crosshead pin; The workpiece clamping module is used to fix and rotate the crosshead pin; and The drive mechanism is used to move the laser emitting mechanism so that the laser beam emitted by the laser emitting mechanism can be evenly irradiated onto the beam processing mechanism.

2. The laser processing device for microtexturing the surface of a crosshead pin in a low-speed diesel engine according to claim 1, characterized in that, The laser emitting mechanism includes a mounting plate (1) and a laser (2) disposed on the mounting plate (1). The mounting plate (1) is fixedly installed on a special laser micro-weaving machine tool. The laser (2) is located directly above the crosshead pin and at the midpoint of the workpiece. The laser (2) is a nanosecond pulsed fiber laser.

3. The laser processing device for microtexturing the surface of a crosshead pin in a low-speed diesel engine according to claim 2, characterized in that, The drive mechanism includes a reducer (3) fixed on the mounting plate (1), a drive motor (4) connected to the reducer (3), a connector for connecting the laser (2) and the mounting plate (1), and a first telescopic component (5) provided on the connector. The connecting component adopts a ball hinge (6), and the first telescopic component (5) is used to drive the laser (2) and the mounting plate (1) to rotate.

4. The laser processing device for microtexturing the surface of a crosshead pin in a low-speed diesel engine according to claim 2, characterized in that, The drive mechanism includes two telescopic components (7) fixedly mounted on the mounting plate (1). The laser (2) and the mounting plate (1) are connected by a ball joint, so that the laser emitting end of the laser (2) can swing freely relative to the mounting plate (1).

5. The laser processing device for microtexturing the surface of a crosshead pin in a low-speed diesel engine according to claim 4, characterized in that, The surface of the laser (2) is provided with an iron protective layer; Both telescopic ends of the two telescopic components (7) are fixedly provided with magnetic components (8) for adsorbing the protective layer.

6. The laser processing device for microtexturing the surface of a crosshead pin in a low-speed diesel engine according to claim 1, characterized in that, The beam processing mechanism includes an arc-shaped plate (10) with several through holes (9) and a refractive element (11) disposed in the through holes (9), wherein the refractive element (11) is a mirror or a prism.

7. The laser processing device for microtexturing the surface of a crosshead pin in a low-speed diesel engine according to claim 2, characterized in that, Two No. 3 telescopic components (12) are fixedly provided on the mounting plate (1). The two No. 3 telescopic components (12) are located at both ends of the arc plate (10). An arc strip (13) is fixedly provided at the telescopic end of the No. 3 telescopic component (12). The arc strip (13) is in contact with the surface of the arc plate (10) and is used to drive the arc plate (10) to deform in order to adapt to different crosshead pins.

8. The laser processing device for microtexturing the surface of a crosshead pin in a low-speed diesel engine according to claim 7, characterized in that, Two brackets (14) are fixedly provided on the mounting plate (1), and the two brackets (14) are respectively located at the bottom of both ends of the arc plate (10); The two telescopic components (12) are respectively fixedly installed on the corresponding brackets (14), and the telescopic direction of the three telescopic components (12) is vertical. The arc-shaped strip (13) is fixedly connected to the surface of the arc-shaped plate (10).

9. A method for controlling the microtexture on the surface of a crosshead pin of a low-speed diesel engine as described in any one of claims 1-8 using a laser processing apparatus, characterized in that, Includes the following steps: S1: Install the crosshead pin onto the workpiece clamping module and automatically align the cylindrical axis; S2: The drive mechanism moves the laser emitting mechanism and the beam processing mechanism above the workpiece. The drive mechanism moves the laser beam on the beam processing mechanism. Laser beams at different irradiation angles are refracted or reflected by the beam processing mechanism and then vertically irradiate the workpiece surface, completing the micro-texture processing of the area covered by the beam processing mechanism. S3: The workpiece clamping module drives the workpiece to rotate, moving the unprocessed area below the beam processing mechanism. Repeat step three until the surface treatment of the entire workpiece is completed.

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