CN-122007602-A - Four-axis galvanometer laser processing device

Abstract

The invention provides a four-axis galvanometer laser processing device, which belongs to the technical field of laser precision processing and galvanometer scanning control and comprises a laser, a three-axis galvanometer scanning module and a rotary light path module, wherein the three-axis galvanometer scanning module comprises a first galvanometer, a second galvanometer and a dynamic focusing unit, the first galvanometer and the second galvanometer are used for controlling light beams to deflect in the X, Y axial direction, the rotary light path module is arranged on an emergent light path of the three-axis galvanometer scanning module and comprises a hollow motor, a hollow motor rotor frame, a first reflecting mirror and a second reflecting mirror which are sequentially arranged along the light path, the first reflecting mirror and the second reflecting mirror are obliquely arranged relative to the rotation axis of the hollow motor, and the hollow motor is used for driving the first reflecting mirror and the second reflecting mirror to integrally rotate so as to enable the emergent laser beams to rotate and scan 360 degrees around the rotation axis of the hollow motor. The invention realizes oblique incidence scanning removal of laser on the side wall of the blind hole, and the system light path is more concise, the required precision elements are less, and the manufacturing and maintenance cost is reduced.

Inventors

• QIN YINGXIONG
• LI YUDA
• LIU XIAODONG

Assignees

• 华中科技大学

Dates

Publication Date

20260512

Application Date

20260323

Claims (10)

1. 1. The four-axis galvanometer laser processing device is characterized by comprising a laser, a three-axis galvanometer scanning module and a rotary light path module; The laser is used for outputting a laser beam (6); The triaxial galvanometer scanning module comprises a dynamic focusing unit, a first galvanometer (7) and a second galvanometer (8) which are arranged along the light path of the laser beam (6), wherein the first galvanometer (7) is used for controlling the deflection of the light beam in the X-axis direction, the second galvanometer (8) is used for controlling the deflection of the light beam in the Y-axis direction, and the dynamic focusing unit is used for adjusting the position of a laser focus in the Z-axis direction; The three-axis vibrating mirror scanning device comprises a three-axis vibrating mirror scanning module, a rotating light path module and a driving module, wherein the rotating light path module is arranged on an emergent light path of the three-axis vibrating mirror scanning module, the rotating light path module comprises a hollow motor (2), a hollow motor rotor frame (5) and an optical component, the hollow motor rotor frame (5) is connected to an output shaft of the hollow motor (2), and the optical component is arranged on the hollow motor rotor frame (5); The optical component is used for deflecting an incident laser beam and then emitting the laser beam at a fixed inclination angle; The hollow motor (2) is used for driving the optical assembly to rotate by taking the theta axis as an axis, so that the emergent laser beam can rotate and scan 360 degrees around the rotation axis of the hollow motor.
2. 2. The four-axis galvanometer laser machining device according to claim 1, wherein the rotation axis of the rotary optical path module coincides with the axis of the blind hole to be machined.
3. 3. The four-axis galvanometer laser processing device according to claim 1, wherein the outgoing end of the rotary optical path module is further provided with a focusing mirror (11), and the focusing mirror (11) is used for focusing the laser beam passing through the rotary optical path module onto the inner side wall of the blind hole.
4. 4. A four-axis galvanometer laser machining apparatus according to claim 3, characterized in that the focusing mirror (11) is a telecentric field lens.
5. 5. The four-axis galvanometer laser beam machine as set forth in claim 1, wherein the dynamic focusing unit is a focusing lens group that moves in the direction of the optical axis, the movement of which is driven by a linear motor.
6. 6. The four-axis galvanometer laser machining apparatus according to claim 1, wherein the fixed inclination angle α is 30 ° or more.
7. 7. A four-axis galvanometer laser machining apparatus according to claim 1, characterized in that the optical assembly comprises a first mirror (3) and a second mirror (4) arranged in sequence along an optical path, the first mirror (3) and the second mirror (4) being each arranged obliquely to the axis of rotation of the hollow motor (2); The first reflecting mirror (3) and the second reflecting mirror (4) are plane reflecting mirrors.
8. 8. The four-axis galvanometer laser machining device according to claim 1, wherein the hollow motor (2) is a direct drive motor.
9. 9. The four-axis galvanometer laser machining apparatus according to any one of claims 1-8, further comprising a control system configured to cooperatively control the X, Y, Z-axis motion of the three-axis galvanometer scanning module and the θ -axis rotational motion of the rotational optical path module so that the laser focus forms a predetermined scanning trajectory on the inner sidewall of the blind hole.
10. 10. The four-axis galvanometer laser machining device of claim 9, wherein the preset scanning track is an annular scanning track which is performed layer by layer along the depth direction of the blind hole.

Description

Four-axis galvanometer laser processing device Technical Field The invention belongs to the technical field of laser precision machining and galvanometer scanning control, and particularly relates to a four-axis galvanometer laser machining device. Background The traditional biaxial galvanometer scanning head realizes in-plane high-speed scanning through X, Y two swinging lenses and is widely used for marking, engraving, welding and micromachining. In order to expand the processing range and adapt to the processing of a three-dimensional curved surface or a deep cavity, the industry has developed a 3D dynamic focusing scanning system which is provided with a Z-axis dynamic focusing module on the basis of X, Y galvanometer, and the accurate focusing in a larger range is realized by moving the focal length to compensate the height of an object plane. The existing three-axis dynamic focusing head generally adopts a 3D scanning head structure that a group of zoom or scanning lenses moving along with a Z axis are added behind an X/Y galvanometer, so that the dynamic adjustment of the working distance and the focal position is realized. Currently, there is a need in the electronics, semiconductor, etc. industries for a process that requires removal after plating a metallic silver layer on the inside walls of blind vias. However, due to the specificity of the blind hole structure, the conventional laser normal incidence mode is difficult to effectively irradiate the silver plating layer on the side wall of the blind hole, so that the removal efficiency and the effect are poor. In order to solve the problem that laser energy is difficult to act on the side wall of the blind hole, various laser oblique incidence processing schemes are proposed in the industry. One common approach is a laser beam rotating galvanometer system, as disclosed in chinese patent CN101856772a, which combines a beam rotating focusing method with galvanometer scanning. The proposal adopts a beam rotator (such as a rotary wedge prism, an off-axis rotary lens and the like) to be arranged on a hollow shaft high-speed motor, so that laser beams are deflected and focused by a vibrating mirror after rotating around the shaft, and the processing similar to spiral punching is realized. The scheme can cut the laser in a spiral track, so that the processing aperture is increased, and slag is discharged conveniently. Another prior art solution is to use an optical wedge/image rotator to achieve oblique incidence and rotation of the beam. For example, U.S. patent No. 7842901B2 proposes to control the aperture roundness by varying the tilt angle of the output beam by rotating an angle-adjustable wedge. In the scheme, the optical wedge not only needs to rotate around the central shaft at a constant speed, but also needs to perform pitching motion to change the incident angle, and the optical wedge belongs to compound motion control. In addition, a commercial five-axis laser scanning system (such as precSYS of SCANLAB company) is available on the market, and the accurate processing of the laser beam at any space dip angle is realized by combining two tilt adjusting shafts and a dynamic focusing shaft through an X/Y biaxial galvanometer. The system can carry out high-precision laser oblique incidence micromachining, and can process complex micropore structures such as cylinders, positive/negative cones and the like. However, the prior art solutions described above all have significant drawbacks: (1) The light beam rotating system adopting the Dove prism and other image rotators needs a high-precision hollow shaft motor and a precision optical element for supporting, and the system has large volume and high price. The five-axis scanning head integrates a multi-axis driving and controlling unit, which also results in high equipment cost and severe maintenance requirements. (2) The alignment and control difficulties are great, the schemes such as rotary wedge prism and the like are used for realizing the high-speed rotation and pitching compound motion of the optical wedge, the control algorithm is complex, and errors are easy to accumulate. When the Dove prism is adopted to rotate, the angle and the optical axis of the Dove prism are accurately calibrated, and synchronous galvanometer scanning is performed, so that the system debugging difficulty is increased. The calibration process of the five-axis linkage system is complex, the laser focus and each axis coordinate are required to be precisely aligned, and the initial alignment and subsequent calibration workload is large. (3) The efficiency and applicability are limited, and part of the schemes realize large-area processing through a two-dimensional motion platform, but the mechanical movement speed is low and the acceleration and deceleration time is long. The normal incidence of the conventional vibrating mirror cannot be conducted on a blind hole with a larger depth and diameter, and the side wall melt i