A laser beam active alignment system and a laser beam active alignment method

Abstract

The application discloses a kind of laser beam active alignment system and laser beam active alignment method, system includes: machine tool, tool is equipped on machine tool, tool can be moved along preset movement path on machine tool, tool and the contact of workpiece to be processed forms cutting point;Machine tool shaft controller is used to control tool along preset movement path, obtain the position information of tool on preset movement path;Laser beam generating component is used to emit laser beam;Laser beam controller can adjust the optical path of laser beam according to the position information of tool on preset movement path provided by machine tool shaft controller, so that the optical path center of laser beam is incident to cutting point.Compared with prior art, the present application receives tool position information provided by machine tool shaft controller in real time through laser beam controller and dynamically adjusts the optical path of laser beam, so that the optical path center of laser beam always coincides with cutting point.

Description

Technical Field

[0001] This invention relates to the field of laser cutting technology, and in particular to an active laser beam alignment system and a method for active laser beam alignment. Background Technology

[0002] Traditional diamond turning processes suffer from severe tool wear and poor surface finish when machining hard and brittle materials. Laser-assisted diamond turning is a hybrid technology that combines single-point diamond turning with laser heating to increase the ductility of hard and brittle materials. A focused laser beam is guided through a transparent tool and exits at the cutting edge in front. During cutting, the laser heats the material around the cutting point, which in turn softens the hard and brittle material and increases tool life.

[0003] Traditional laser-assisted diamond turning technology has the following limitations: Fixed cutting point and laser beam center: In existing technologies, the laser beam center is fixed at a certain position on the cutting edge and cannot be dynamically adjusted according to changes in the slope of the machined surface. This results in the laser beam failing to effectively cover the cutting point when machining workpieces with large changes in surface angle, reducing machining efficiency and tool life.

[0004] Limited laser beam coverage: For large-diameter lenses or deeply concave molds, existing technology cannot use the optimal tool radius for machining because the laser beam cannot cover the entire cutting point.

[0005] High laser power requirements: In order to cover a larger angular change, a larger defocus is required, which reduces the effective laser power at each cutting point. This must be compensated for by increasing the input laser power, which leads to problems such as thermal instability and scorching. Summary of the Invention

[0006] The purpose of this invention is to provide a laser beam active alignment system and a laser beam active alignment method to solve the technical problems in the prior art. It can dynamically adjust the position of the laser beam during the cutting process so that it is always aligned with the actual cutting point.

[0007] In a first aspect, the present invention provides a laser beam active alignment system, comprising: A machine tool is provided with a cutting tool, which can move along a preset movement path on the machine tool. The cutting tool is used to process a workpiece, and the cutting tool contacts the workpiece to form a cutting point. A machine tool axis controller is used to control the tool along the preset movement path and to obtain the position information of the tool on the preset movement path. Laser beam generating component, used to emit a laser beam; The laser beam controller can adjust the optical path of the laser beam according to the position information of the tool on the preset movement path provided by the machine tool axis controller, so that the center of the laser beam is incident on the cutting point.

[0008] In the laser beam active alignment system described above, preferably, the tool can move along the X-axis, Y-axis, or Z-axis direction on the machine tool, wherein the X-axis, Y-axis, and Z-axis directions are perpendicular to each other.

[0009] In the laser beam active alignment system described above, preferably, the laser beam generating component includes a laser source, an optical fiber, a collimator, and a focusing lens arranged sequentially along the optical path. The laser source generates a laser beam and transmits it via coupling through the optical fiber. The optical fiber transmits the laser beam generated by the laser source to the collimator. The collimator collimates the laser beam in the optical fiber into parallel light. The focusing lens focuses the collimated laser beam at the cutting point.

[0010] In the laser beam active alignment system described above, preferably, the collimator is mounted on an electric laser stage so that the collimator can move along the J-axis, K-axis and L-axis directions, wherein the J-axis, K-axis and L-axis directions are perpendicular to each other.

[0011] In the laser beam active alignment system described above, preferably, the laser beam controller acquires the position information of the tool on the preset movement path provided by the machine tool axis controller in real time, and calculates the spatial coordinates of the current cutting point based on the position information to generate movement commands for the electric laser stage in the J-axis direction, the K-axis direction, and the L-axis direction, so that the collimator moves to dynamically adjust the optical path center of the laser beam.

[0012] In the laser beam active alignment system described above, preferably, the focusing lens has an adjustable focal length.

[0013] In the laser beam active alignment system described above, preferably, the cutting tool is a transparent single-point diamond turning tool.

[0014] In the laser beam active alignment system described above, preferably, the laser beam passes through the interior of the tool and irradiates the cutting point from the front of the cutting edge of the tool. In the laser beam active alignment system described above, preferably, the laser beam controller and the machine tool axis controller are connected via a real-time communication interface.

[0015] Secondly, the present invention also provides a laser beam active alignment method, which applies the aforementioned laser beam active alignment system and includes the following steps: The machine tool axis controller is used to control the tool to move along a preset movement path, and the position information of the tool on the preset movement path is acquired in real time. The laser beam controller reads the position information of the tool on the preset movement path provided by the machine tool axis controller, and calculates the spatial coordinates of the current cutting point based on the position information; The laser beam controller adjusts the optical path of the laser beam according to the coordinates of the cutting point, so that the center of the laser beam is incident on the cutting point.

[0016] Compared to existing technologies, this invention uses a laser beam controller to receive tool position information from the machine tool axis controller in real time and dynamically adjusts the laser beam path to ensure that the center of the laser beam path always coincides with the cutting point. Through dynamic alignment, a narrower laser beam can be directly focused on the area in contact with the workpiece, thereby reducing laser input power, minimizing heat-affected zones, scorching, and residual stress. This allows for the use of diamond tools with larger nose radii to improve material removal rates and tool life. When machining workpieces with high surface angles, this invention can significantly improve tool life and reduce tool wear. Attached Figure Description

[0017] Figure 1 This is a structural block diagram of the laser beam active alignment system provided in an embodiment of the present invention.

[0018] Explanation of reference numerals in the attached diagram: 1-Machine tool, 2-Cutting tool, 3-Laser source, 4-Fiber optic cable, 5-Collimator, 6-Focusing lens, 7-Electric laser stage, 8-Laser beam controller, 9-Machine tool axis controller. Detailed Implementation

[0019] The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0020] like Figure 1 As shown, an embodiment of the present invention provides a laser beam active alignment system. The system integrates laser beam control and tool motion control to achieve real-time dynamic alignment of the laser beam with the cutting point during machining, thereby improving machining accuracy and efficiency and overcoming problems such as laser beam misalignment and low energy utilization in traditional technologies. Specifically, the system includes a machine tool 1, a machine tool axis controller 9, a laser beam generating component, and a laser beam controller 8.

[0021] The machine tool 1 is equipped with a cutting tool 2, which can move along a preset path on the machine tool 1. The cutting tool 2 is used to process the workpiece. The cutting tool 2 contacts the workpiece to form a cutting point, which is also the target reference point for the laser beam to be aligned. During the processing, the position of the cutting point changes continuously as the contact area between the cutting tool 2 and the workpiece changes.

[0022] The machine tool axis controller 9 is used to control the tool 2 along a preset movement path and obtain the position information of the tool 2 on the preset movement path. The machine tool axis controller 9 obtains the actual spatial coordinates of the tool 2 in real time through high-precision sensing devices such as servo motor encoders and grating rulers and transmits them synchronously to the laser beam controller 8.

[0023] The laser beam generating component is used to emit a controllable and focused laser beam. The laser beam locally heats the workpiece, improves the workpiece's plasticity, softens the material locally, reduces cutting force, extends tool life, and improves the surface quality of the machined part.

[0024] The laser beam controller 8 adjusts the optical path of the laser beam based on the position information of the tool 2 on the preset movement path provided by the machine tool axis controller 9, so that the center of the laser beam is incident on the cutting point. The laser beam controller 8 receives the tool 2 position information sent by the machine tool axis controller 9 to obtain the spatial coordinates of the current cutting point, and adjusts the laser beam direction accordingly to achieve spatial tracking and alignment of the laser beam. Through dynamic alignment, a narrower laser beam can be directly focused on the area in contact with the workpiece, thereby reducing laser input power, heat-affected zone, scorching, and residual stress. This allows for the use of diamond tools 2 with larger nose radius to improve material removal rate and tool life. When machining workpieces with high surface angles, this invention can significantly improve tool life and reduce tool wear.

[0025] In the embodiments provided in this disclosure, the tool 2 can move along the X-axis, Y-axis, or Z-axis on the machine tool 1, and the X-axis, Y-axis, and Z-axis are perpendicular to each other. The tool 2 has three linear degrees of freedom in three directions, and the three movement directions (X-axis, Y-axis, and Z-axis) are mutually perpendicular, forming a Cartesian coordinate system. This ensures that the position of any point of the tool 2 in space can be described by a unique coordinate (x, y, z), providing a deterministic basis for the subsequent spatial vector calculation of the laser beam.

[0026] In one feasible implementation, the tool 2 is carried on the slide, the machine tool axis controller 9 outputs the target coordinates, and the machine tool 1 feed system (e.g., servo motor + ball screw) independently drives the slide in the X-axis, Y-axis and Z-axis directions. Each axis direction is equipped with a position detection element (e.g., grating ruler, magnetic grating or encoder) to output axis coordinate feedback value in real time. This feedback value is the position information of the tool 2, which is used for the subsequent spatial coordinate transformation of the laser beam controller 8.

[0027] In the embodiments provided in this application, the laser beam generating component includes a laser source 3, an optical fiber 4, a collimator 5, and a focusing lens 6 arranged sequentially along the optical path, forming a unidirectional optical link.

[0028] Laser source 3 is used to generate a laser beam and transmit it through optical fiber 4. As the starting point of the optical path, laser source 3 has its emitting surface directly or indirectly coupled to the incident end face of optical fiber 4, converting the divergent light into waveguide-confined light.

[0029] Fiber 4 is used to transmit the laser beam generated by laser source 3 to collimator 5, providing collimator 5 with constant incident conditions.

[0030] Collimator 5 is located after the output end of fiber 4. Collimator 5 is used to collimate the laser beam in fiber 4 into parallel light. Collimator 5 can convert the conical diverging beam into parallel light with a very small divergence angle. The diameter of the parallel light remains unchanged during subsequent propagation.

[0031] The focusing lens 6 is used to focus the collimated, parallel laser beam onto the cutting point. As the optical path terminator, the focusing lens 6 highly concentrates the energy of the parallel light in space and focuses it onto the instantaneous cutting point formed by the contact between the cutting edge of the tool 2 and the workpiece. Although the tool 2 moves continuously during the machining process, the laser beam controller 8 can control the collimated laser beam to be stably focused on the cutting point.

[0032] In one feasible implementation, the collimator 5 is mounted on the electric laser stage 9 and fixedly connected to the electric laser stage 9, enabling the collimator 5 to move synchronously with the tool 2. The collimator 5 can move along the J-axis, K-axis, and L-axis, which are perpendicular to each other. The collimator 5 has three linear degrees of freedom in three directions, and the three movement directions (J-axis, K-axis, and L-axis) are mutually perpendicular, forming a Cartesian coordinate system. This ensures that when the collimator 5 moves along any single axis, it will not introduce offsets in other axes.

[0033] The spatial displacement vector (J, K, L axis vectors) of collimator 5 can be uniformly transformed with the spatial displacement vector (X, Y, Z axis vectors) of tool 2. The laser beam can be spatially displaced synchronously with tool 2 before entering focusing lens 6. According to the lens imaging principle of focusing lens 6, the change in incident eccentricity will be linearly reflected as the lateral shift of the focal point on the object surface, while the beam direction of the laser beam remains parallel to the optical axis of the lens, so that the laser beam is always aligned with the cutting point, reducing energy dispersion and thermal effects caused by laser beam deflection, and improving the tool life.

[0034] In one feasible implementation, the laser beam controller 8 acquires the position information of the tool 2 on the preset movement path provided by the machine tool axis controller 9 in real time. The laser beam controller 8 can grasp the spatial posture of the tool 2 in real time, thereby obtaining the instantaneous spatial coordinates of the cutting point.

[0035] The laser beam controller 8 calculates the spatial coordinates of the current cutting point based on the position information, and generates movement commands for the motorized laser stage 9 in the J-axis, K-axis, and L-axis directions, causing the collimator 5 to move to dynamically adjust the optical path center of the laser beam. After obtaining the cutting point coordinates, the laser beam controller 8 can perform reverse optical path calculation, that is, using the focusing lens 6 as a reference, it projects the target position of the cutting point in reverse onto the output plane of the collimator 5, thereby obtaining the spatial coordinate points required for the output optical axis of the collimator 5. The laser beam controller 8 then transmits these spatial coordinate points to the motorized laser stage 9, generating movement commands in the J-axis, K-axis, and L-axis directions. The motorized laser stage 9 drives the collimator 5 to move according to these commands, thereby moving the starting point of the parallel light beam to a position where the focused spot falls on the cutting point.

[0036] Preferably, the focusing lens 6 has an adjustable focal length. The focusing lens 6 can achieve active zoom, no longer limited to a fixed focal length. By changing the focal length in real time, the focusing lens 6 can adjust the axial distance between the focal point and the lens principal surface in real time, thereby adapting to the depth changes of the tool 2 along the Z-axis or the differences in the height of different workpieces.

[0037] If the tool 2 changes in depth along the preset movement path, the machine tool axis controller 9 sends the Z-axis coordinate to the laser beam controller 8 in real time. The laser beam controller 8 first calculates the focal position using the cutting point coordinates, then compares it with the focal axial position provided by the current focal length to obtain the deviation. Subsequently, the focusing lens 6 adjusts the focal length so that the focal point moves along the optical axis to coincide with the cutting point.

[0038] In the embodiments provided in this application, the tool 2 is a transparent single-point diamond turning tool 2. The laser beam passes through the interior of the tool 2 and irradiates the cutting point from the front of the cutting edge. The laser beam can be incident along the body of the tool 2. When the laser beam travels inside the tool 2, it forms a stable light guide trajectory and then exits from the front of the cutting edge, directly acting on the workpiece material near the cutting point to locally soften the surface of the workpiece. This achieves a compact optical path layout, with the laser beam's exit point closer to the cutting point, avoiding the laser beam being blocked due to changes in surface slope when incident laterally. Especially in the machining of complex curved or deeply concave surfaces, it can ensure that the laser beam energy is always injected forward into the cutting edge, reducing the risk of alignment failure.

[0039] The laser beam controller 8 and the machine tool axis controller 9 are connected via a real-time communication interface. This allows the spatial position information of the tool 2 to be immediately forwarded to the laser beam controller 8 via the real-time communication interface as it is generated. Upon receiving the information, the laser beam controller 8 completes coordinate calculation, generates optical path correction commands, and drives the electric laser stage 9 to move within the same cycle. This ensures that the spatial displacement vectors (J, K, L axis vectors) of the collimator 5 correspond to the spatial displacement vectors (X, Y, Z axis vectors) of the tool 2, keeping the laser beam adjustment in phase with the movement of the tool 2 and avoiding energy shift caused by laser beam movement lag.

[0040] Secondly, the present invention also provides a laser beam active alignment method, which applies the aforementioned laser beam active alignment system and includes the following steps: Step S101: Use the machine tool axis controller 9 to control the tool 2 to move along the preset movement path, and obtain the position information of the tool 2 on the preset movement path in real time.

[0041] Step S102: Use the laser beam controller 8 to read the position information of the tool 2 on the preset movement path provided by the machine tool axis controller 9, and calculate the spatial coordinates of the cutting point based on the position information.

[0042] Step S103: The laser beam controller 8 adjusts the optical path of the laser beam according to the coordinates of the cutting point, so that the center of the laser beam is incident on the cutting point.

[0043] Through the aforementioned active laser beam alignment method, the laser beam controller 8 receives the tool 2 position information sent by the machine tool axis controller 9, obtains the spatial coordinates of the current cutting point, and adjusts the laser beam direction accordingly to achieve spatial tracking alignment of the laser beam. Dynamic alignment allows for the direct focusing of a narrower laser beam onto the area in contact with the workpiece, thereby reducing laser input power, minimizing heat-affected zones, scorching, and residual stress. This allows for the use of diamond tools 2 with larger nose radii to improve material removal rate and tool life. When machining workpieces with high surface angles, this invention can significantly improve tool life and reduce tool wear.

[0044] The above description, based on the embodiments shown in the figures, details the structure, features, and effects of the present invention. The above description is only a preferred embodiment of the present invention, but the present invention is not limited to the scope of implementation shown in the figures. Any changes made in accordance with the concept of the present invention, or equivalent embodiments modified to have equivalent changes, that do not exceed the spirit covered by the specification and figures, should be within the protection scope of the present invention.

Claims

1. A laser beam active alignment system, characterized by, include: A machine tool is provided with a cutting tool, which can move along a preset movement path on the machine tool. The cutting tool is used to process a workpiece, and the cutting tool contacts the workpiece to form a cutting point. A machine tool axis controller is used to control the tool along the preset movement path and to obtain the position information of the tool on the preset movement path. Laser beam generating component, used to emit a laser beam; The laser beam controller can adjust the optical path of the laser beam according to the position information of the tool on the preset movement path provided by the machine tool axis controller, so that the center of the laser beam is incident on the cutting point.

2. The laser beam active alignment system of claim 1, wherein, The cutting tool can move along the X-axis, Y-axis or Z-axis on the machine tool, and the X-axis, Y-axis and Z-axis are perpendicular to each other.

3. The laser beam active alignment system of claim 1, wherein, The laser beam generating assembly includes a laser source, an optical fiber, a collimator, and a focusing lens arranged sequentially along the optical path. The laser source generates a laser beam and transmits it via coupling through the optical fiber. The optical fiber transmits the laser beam generated by the laser source to the collimator. The collimator collimates the laser beam in the optical fiber into parallel light. The focusing lens focuses the collimated laser beam at the cutting point.

4. The laser beam active alignment system of claim 3, wherein, The collimator is mounted on an electric laser stage so that it can move along the J-axis, K-axis and L-axis directions, which are perpendicular to each other.

5. The laser beam active alignment system of claim 4, wherein, The laser beam controller acquires the position information of the tool on the preset movement path provided by the machine tool axis controller in real time, and calculates the spatial coordinates of the current cutting point based on the position information to generate movement commands for the electric laser stage in the J-axis direction, the K-axis direction, and the L-axis direction, so that the collimator moves to dynamically adjust the optical path center of the laser beam.

6. The laser beam active alignment system of claim 4, wherein, The focusing lens has an adjustable focal length.

7. The laser beam active alignment system of claim 1, wherein, The cutting tool is a transparent single-point diamond turning tool.

8. The laser beam active alignment system of claim 7, wherein, The laser beam passes through the interior of the tool and illuminates the cutting point from the front of the cutting edge.

9. The laser beam active alignment system of claim 1, wherein, The laser beam controller and the machine tool axis controller are connected via a real-time communication interface.

10. A method of active alignment of a laser beam, characterized in that, The active laser beam alignment system according to any one of claims 1-9 includes the following steps: The machine tool axis controller is used to control the tool to move along a preset movement path, and the position information of the tool on the preset movement path is acquired in real time. The laser beam controller reads the position information of the tool on the preset movement path provided by the machine tool axis controller, and calculates the spatial coordinates of the current cutting point based on the position information; The laser beam controller adjusts the optical path of the laser beam according to the coordinates of the cutting point, so that the center of the laser beam is incident on the cutting point.

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