High-speed dynamic focus tracking laser scanning system

Abstract

The utility model relates to the technical field of laser processing, in particular to a high-speed dynamic focus tracking laser scanning system, which comprises a dichroscope, a light beam zooming unit and a galvanometer unit which are sequentially arranged on a path of a laser beam, and a visual inspection unit positioned outside the path. Wherein the light beam zooming unit is configured to be capable of focusing a laser beam and adjusting the focal length of the laser beam; the dichroscope is configured to allow the laser beam to pass through; the detection end of the visual detection unit is configured to be capable of obtaining an image of a printed piece formed on the printing plane through the dichroscope and the galvanometer unit. In the printing process, the image of the printed piece formed on the printing plane is reflected to the detection end of the visual detection unit through the galvanometer unit and the dichroscope, whether the formed printed piece deviates from the preset printing position or not can be recognized through the image obtained by the visual detection unit, and splicing dislocation can be monitored in real time in the printing process; and therefore, splicing correction can be conveniently carried out on a splicing dislocation position.

Description

Technical Field

[0001] This utility model relates to the field of laser processing technology, specifically to a high-speed dynamic tracking laser scanning system. Background Technology

[0002] Laser 3D printing prints three-dimensional objects using a laser scanning system. The basic process is as follows: a powder feeding device delivers a certain amount of powder to the work platform, a powder spreading device spreads a layer of powder material evenly on the bottom plate of the forming cylinder or the upper surface of the already formed part, and a laser galvanometer system controls the laser to scan the solid powder layer according to the cross-sectional contour of the layer with an approximately constant spot size and beam energy, causing the powder to melt and bond with the already formed part below. After one layer of cross-section is sintered, the work platform descends by the thickness of one layer, and the powder spreading device spreads another layer of uniform and dense powder on top, and a new layer of cross-section is scanned and sintered. After several layers are scanned and superimposed, the entire three-dimensional object is manufactured.

[0003] Currently, in order to achieve high efficiency and large-format printing, multiple laser scanning systems are mainly used for printing simultaneously. During the forming process, multiple laser scanning systems work simultaneously in their respective zones, and the zones are spliced ​​together to form a complete printed pattern, which multiplies the forming size and forming efficiency of the equipment.

[0004] While using multiple scanning systems simultaneously for printing can improve efficiency, several issues remain: First, misalignment in the XY direction is common at the laser junction of the formed parts. Currently, misalignment correction is primarily performed before printing. However, even with pre-printing correction, the galvanometer can still drift during printing due to environmental changes such as temperature, humidity, and vibration, as well as mechanical wear of the galvanometer motor, leading to misalignment. Second, the laser beam spot projected onto the printing plane is also prone to Z-axis shift during printing due to environmental factors like temperature and vibration, causing the focal point to deviate from the printing plane. Utility Model Content

[0005] To address the aforementioned deficiencies, the technical problem to be solved by this utility model is to provide a high-speed dynamic tracking laser scanning system that can monitor the splicing offset during the printing process and thus perform real-time correction.

[0006] The above-mentioned technical objective of this utility model is achieved through the following technical solution:

[0007] A high-speed dynamic tracking laser scanning system includes a dichroic mirror, a beam zoom unit, and a galvanometer unit arranged sequentially along the path of a laser beam, as well as a visual detection unit located outside the path.

[0008] The beam zoom unit is configured to focus the laser beam and adjust the focal length of the laser beam.

[0009] The galvanometer unit is configured to reflect the laser beam onto the printing plane and to adjust the planar position of the laser beam reflected onto the printing plane.

[0010] The dichroic mirror is configured to allow the laser beam to pass through;

[0011] The detection end of the visual inspection unit is configured to acquire an image of the printed part formed on the printing plane through a dichroic mirror and a galvanometer unit.

[0012] By adopting the above scheme, during use, the laser beam passes sequentially along the path through a dichroic mirror and a beam zoom unit to reach the galvanometer unit. The beam zoom unit focuses the laser beam, and the galvanometer unit adjusts the position of the laser beam reflected onto the printing plane. The image of the printed part formed on the printing plane is reflected by the galvanometer unit and the dichroic mirror to the detection end of the vision inspection unit. The data obtained by the detection end of the vision inspection unit can identify whether the formed printed part deviates from the preset printing position, and can reflect any splicing misalignments, enabling real-time monitoring of splicing misalignments during the printing process. Based on the splicing misalignment information, before scanning and printing the next layer, the galvanometer unit adjusts the scanning path of the laser beam on the printing plane to correct the splicing misalignments. In this process, the galvanometer unit adjusts the position of the laser beam reflected onto the printing plane during the printing process, thereby scanning the printing plane according to a preset path. During the scanning process, the galvanometer unit can reflect the images of the part being scanned and the adjacent parts that have already been scanned onto the dichroic mirror. The dichroic mirror reflects the images onto the detection end of the vision detection unit, thereby enabling real-time acquisition of the forming status of the printed part formed on the scanning path.

[0013] Preferably, the beam zoom unit includes a focusing lens group, a diverging lens, and a linear drive mechanism. The diverging lens is fixed to the working end of the linear drive mechanism. The laser beam first passes through the diverging lens and then through the focusing lens group. The linear drive mechanism is used to adjust the distance between the diverging lens and the focusing lens group, thereby adjusting the focal length of the laser beam. During the printing process, the distance from each point on the printing plane to the reflector of the galvanometer unit is different. The focal length of the laser beam can be adjusted in real time according to the requirements of the laser scanning path, so that the laser beam can be accurately focused on the printing plane for printing operations.

[0014] Preferably, the beam zoom unit further includes a first housing, in which the focusing lens group, diverging lens, and linear drive mechanism are all fixedly installed. Both ends of the first housing have first apertures for the laser beam to pass through. The first housing isolates external light interference and provides dust protection, ensuring the stability of the working environment during printing.

[0015] Preferably, the first housing contains a heat exchange plate with a second aperture for the laser beam to pass through. The heat exchange plate contains two first cooling medium channels, each with a medium interface at its first end extending outside the first housing. The first housing also contains a second cooling medium channel, with its inlet and outlet connected to the second ends of the two first cooling medium channels, respectively. In use, cooling medium is introduced into the first medium interface. The cooling medium flows sequentially through the first, second, and third first cooling medium channels, dissipating heat from the first housing and the heat sink, preventing thermal expansion of the material due to temperature rise, and thus improving stability.

[0016] Preferably, the system also includes a second housing, which is fixedly connected to the front end of the first housing. Both ends of the second housing have third apertures for the laser beam to pass through, and the detection end of the vision inspection unit is disposed within the second housing. Because the detection end of the vision inspection unit is disposed within the second housing, interference during the reflection of the image of the printed surface from the galvanometer unit and dichroic mirror to the detection end of the vision inspection unit can be reduced, thereby ensuring that the detection end can detect accurate data.

[0017] Preferably, the system also includes a spot detection component located at one end of the galvanometer unit. This spot detection component includes a mounting base, a window, a spot detection unit, and a reflection unit. The mounting base has a beam channel. The window is used to split the laser beam projected onto it into a reflected beam and a transmitted beam. The window is located within the beam channel and at its exit end. The spot detection unit detects the spot projected onto its detection end. The reflection unit reflects the reflected beam of the laser beam projected onto a preset position on the window back to the detection end of the spot detection unit. In use, the laser beam enters the beam channel. When the laser beam is projected onto the preset position on the window, it is split into a reflected beam and a transmitted beam. The transmitted beam is used for printing in the printing area. The reflected beam is reflected by the reflection unit to the detection end of the spot detection unit, where the spot is identified to obtain its shape information. Because the transmitted beam can still print while the reflected beam is being detected, spot detection can be performed during the printing process, allowing for online correction of the spot's shape. Furthermore, since the reflected laser beam has low energy, there is no need to design an energy attenuation system to protect the detection end, making the overall structure compact and small, with better space advantages.

[0018] Preferably, the window is configured to close the exit end of the beam channel. Because the window closes the exit end of the beam channel, the reflection unit is separated from the printing area, preventing mutual interference.

[0019] Preferably, the mounting base has a third cooling medium channel inside, with both the inlet and outlet of the third cooling medium channel located on the outside of the mounting base. Since the laser beam generates heat during operation, introducing cooling medium into the third cooling medium channel can reduce the temperature of the mounting base and its interior.

[0020] Preferably, the mounting base has a first mounting port on its side, and the reflecting unit is disposed within the first mounting port. The reflecting unit includes a third housing and a mirror assembly disposed inside it. The third housing is fixedly connected to the first mounting port, and the spot detection unit is fixedly connected to the third housing. The third housing has a light inlet corresponding to the first mounting port and a light outlet corresponding to the detection end of the spot detection unit. The mirror assembly is configured to reflect the reflected beam of the laser beam projected at the preset position to the detection end of the spot detection unit. Because the mirror assembly is disposed inside the housing, the influence of the external environment on the mirror assembly is reduced.

[0021] Preferably, the reflector group includes a first reflector, a second reflector, and a third reflector. The first and second reflectors are arranged in parallel. The reflected beam of the laser beam projected at the preset position is reflected by the first and second reflectors and then onto the third reflector. The third reflector is configured to reflect the reflected beam projected onto it to the detection end of the spot detection unit. The path length of the reflected beam to the detection end of the spot detection unit is equal to the path length of the transmitted beam to the printing plane. Since the length of the reflected beam needs to be the same as the length of the transmitted beam, the true information of the spot transmitted by the transmitted beam in the printing area can be reflected. Because the first and second reflectors are parallel to each other, the reflected beam can be reflected multiple times between the first and second reflectors, thereby meeting the path length requirement of the reflected beam and reducing the overall length of the reflector unit.

[0022] In summary, the high-speed dynamic focusing laser scanning system provided by this utility model has at least the following beneficial effects:

[0023] 1. It can monitor splicing misalignment in real time during the laser scanning and printing process and correct the splicing misalignment.

[0024] 2. It can dynamically track the spatial coordinates of the laser beam's focal point in the X, Y, and Z axes, thus ensuring the accuracy of the focal point's spatial position. Furthermore, the beam zoom unit and galvanometer unit can collaboratively adjust the spatial coordinates of the laser beam's focal point in the X, Y, and Z axes. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without any novel effort.

[0026] Figure 1 This is a three-dimensional structural schematic diagram of the present invention;

[0027] Figure 2 This is a three-dimensional structural diagram of the beam zoom unit in this utility model;

[0028] Figure 3 This is a front view of the beam zoom unit in this utility model;

[0029] Figure 4 yes Figure 3 Sectional view at point AA;

[0030] Figure 5This is an assembly diagram of the second housing, dichroic mirror, visual inspection unit, and laser collimator from the front view of this utility model.

[0031] Figure 6 This is an assembly diagram of the second housing, dichroic mirror, visual inspection unit, and laser collimator from a rear view in this utility model.

[0032] Figure 7 This is a three-dimensional structural diagram of the spot detection component in this utility model from a top-down perspective;

[0033] Figure 8 This is a three-dimensional structural diagram of the light spot detection component in this utility model from an upward viewing angle;

[0034] Figure 9 This is a front view of the spot detection component in this utility model;

[0035] Figure 10 yes Figure 9 Sectional view at point BB;

[0036] Figure 11 yes Figure 10 An enlarged view of point a in the middle;

[0037] Figure 12 This is a three-dimensional structural diagram of the mounting base in this utility model;

[0038] Figure 13 This is a perspective view of the mounting base in this utility model from a side view.

[0039] Figure 14 This is a perspective view of the heat exchange plate in this utility model from the front side.

[0040] The reference numerals in the accompanying drawings include: dichroic mirror 1, beam zoom unit 2, focusing lens group 201, first lens 2011, second lens 2012, diverging mirror 202, linear drive mechanism 203, voice coil motor 2031, second mounting base 2032, second through hole 2033, first housing 204, bottom housing 2041, cover plate 2042, first aperture 205, heat exchange plate 206, second aperture 207, first cooling medium channel 208, medium interface 209, first mounting base 210, first through hole 211, first lens barrel 212, second lens barrel 213, galvanometer unit 3, and vision inspection unit 4. Second housing 5, third aperture 6, mounting base 7, window plate 8, reflection unit 9, third housing 901, mirror group 902, first mirror 9021, second mirror 9022, third mirror 9023, light outlet 903, second mirror base 904, spot detection unit 10, beam channel 11, laser beam 12, reflected beam 13, transmitted beam 14, third cooling medium channel 15, first mounting port 16, first mirror base 17, clearance hole 18, second mounting port 19, end cap 20, third through hole 21, laser collimator 22, attenuation filter 23, vent hole 24, flange 25. Detailed Implementation

[0041] To enable those skilled in the art to better understand the technical solution of this utility model, the following description is provided in conjunction with the appendix. Figure 1-14 The present invention will be further described in detail below with reference to specific embodiments.

[0042] Please see Figure 1-14 This embodiment provides a high-speed dynamic focusing laser scanning system, comprising: a laser collimator 22, a dichroic mirror 1, a beam zoom unit 2, and a galvanometer unit 3 arranged sequentially from front to back along the path of a laser beam 12, and a vision detection unit 4 located outside the path. The beam zoom unit 2 is configured to focus the laser beam 12 and adjust its focal length; the galvanometer unit 3 is configured to reflect the laser beam 12 onto a printing plane and adjust the planar position of the laser beam 12 reflected onto the printing plane; the dichroic mirror 1 is configured to allow the laser beam 12 to pass through; and the detection end of the vision detection unit 4 is configured to acquire an image of the printed part formed on the printing plane through the dichroic mirror 1 and the galvanometer unit 3. The dichroic mirror 1 is prior art; specifically, it can be a prior art dichroic mirror capable of allowing a 1064nm wavelength laser beam to pass through and reflecting visible light with wavelengths from 340nm to 780nm.

[0043] Please see Figure 4The beam zoom unit 2 includes a focusing lens group 201, a diverging lens 202, and a linear drive mechanism 203 arranged sequentially from left to right. The diverging lens 202 is fixed to the working end of the linear drive mechanism 203. The laser beam 12 enters from the front side of the beam zoom unit 2 and exits from the rear side. The laser beam 12 first passes through the diverging lens 202 and then through the focusing lens group 201. The linear drive mechanism 203 is used to adjust the distance between the diverging lens 202 and the focusing lens group 201, thereby adjusting the focal length of the laser beam 12 passing through the focusing lens group 201. The focusing lens group 201 includes a first lens 2011 and a second lens 2012. The first lens 2011 is located to the right of the second lens 2012. The laser beam 12 passes through the first lens 2011 and then through the second lens 2012. The left side of the first lens 2011 is convex, and the right side is flat; both sides of the second lens 2012 are convex; the diverging lens 202 is a lens with both sides being concave.

[0044] Please see Figure 2 The beam zoom unit 2 also includes a first housing 204. The focusing lens group 201, the diverging lens 202, and the linear drive mechanism 203 are all fixedly installed inside the first housing 204. Both ends of the first housing 204 are provided with first apertures 205 for the laser beam 12 to pass through. Please continue reading. Figure 4 Specifically, the first housing 204 includes a bottom housing 2041 and a cover plate 2042. The bottom housing 2041 has an opening on its upper side. The cover plate 2042 is bolted to the upper side of the bottom housing 2041, and the cover plate 2042 closes the upper opening of the bottom housing 2041. The first optical aperture 205 is specifically opened at both ends of the bottom housing 2041. A first fixing seat 210 is fixedly installed inside the first housing 204. The first fixing seat 210 is fixed to the bottom housing 2041 by bolts. A first through hole 211 for the laser beam 12 to pass through is opened in the middle of the first fixing seat 210. A first lens barrel 212 is bolted to the left side of the first fixing seat 210. A second lens barrel 213 is sleeved on the outside of the first lens barrel 212. The focusing lens group 201 is fixed to the inner side of the left section of the second lens barrel 213.

[0045] Please continue reading. Figure 4The first housing 204 contains a heat exchange plate 206, with a second aperture 207 in the middle for the laser beam 12 to pass through. The heat exchange plate 206 contains two first cooling medium channels 208, each with a medium interface 209 extending outside the first housing 204. The first housing 204 contains a second cooling medium channel, with its inlet and outlet connected to the second ends of the two first cooling medium channels 208. The second cooling medium channel is specifically located inside the bottom plate on the lower side of the bottom housing 2041. Its outlet and inlet are both located on the upper surface of the bottom plate, and are connected to the second ends of the two first cooling medium channels 208, i.e., their lower ends. The distribution of the first cooling medium channels 208 on the heat exchange plate 206 is detailed below. Figure 14 .

[0046] Please continue reading. Figure 4 The linear drive mechanism 203 includes a second fixed base 2032 and a voice coil motor 2031. The second fixed base 2032 is fixedly connected inside the first housing 204. A second through hole 2033 for the laser beam 12 to pass through is opened in the middle of the second fixed base 2032, and the second fixed base 2032 is located near the right end of the first housing 204. The stator of the voice coil motor 2031 is fixedly mounted on the second fixed base 2032, and the mover of the voice coil motor 2031 is fixedly connected to the diverging mirror 202. The mover of the voice coil motor 2031 can drive the diverging mirror 202 closer to and further away from the group of diverging mirrors 202.

[0047] Please see Figure 1 , Figure 5 and Figure 6 The system also includes a second housing 5, which is fixedly connected to the front end of the first housing 204. Both the front and rear ends of the second housing 5 have third light holes 6 for the laser beam 12 to pass through. The detection end of the vision inspection unit 4 is located inside the second housing 5. A first mirror mount 17 is fixedly installed inside the second housing 5. The first mirror mount 17 has a clearance hole 18 for the laser beam 12 to pass through, and a dichroic mirror 1 is fixedly installed on the first mirror mount 17. The vision inspection unit 4 is existing technology and can specifically be an industrial camera. To facilitate the installation of the first mirror mount 17 and the dichroic mirror 1, a second mounting port 19 is provided on the right side of the second housing 5. An end cap 20 is detachably connected to the second mounting port 19. The end cap 20 has a third through hole 21 for the detection end of the vision inspection unit 4 to pass through, and the vision inspection unit 4 is detachably connected to the right side of the end cap 20.

[0048] The galvanometer unit 3 is existing technology. It is a 2D galvanometer unit, specifically comprising an X-axis galvanometer, a Y-axis galvanometer, a first motor, and a second motor. The first motor drives the X-axis galvanometer to deflect, and the second motor drives the Y-axis galvanometer to deflect. By driving the X-axis galvanometer to deflect using the first motor, the reflection angle of the X-axis galvanometer is adjusted, thereby adjusting the position of the laser beam 12 projected onto the printing plane in the X-axis direction. Similarly, by driving the Y-axis galvanometer to deflect using the second motor, the reflection angle of the Y-axis galvanometer is adjusted, thereby adjusting the position of the laser beam 12 projected onto the printing plane in the Y-axis direction. Through the cooperation of the X-axis and Y-axis galvanometers, the position of the laser beam 12 projected onto the printing plane can be adjusted to any position. In use, the laser beam 12 enters from the inlet end on the front side of the galvanometer unit, passes through the outlet on the lower side of the galvanometer unit 3, and reaches the printing plane.

[0049] Please see Figure 1 and Figure 7-13 The system also includes a spot detection component located at the light-emitting end of the galvanometer unit 3, positioned below the galvanometer unit 3. Specifically, the spot detection component includes a mounting base 7, a window 8, a spot detection unit 10, and a reflection unit 9. The mounting base 7 has a beam channel 11, with its upper end as the entrance and its lower end as the exit. The window 8 is used to divide the laser beam 12 projected onto it into a reflected beam 13 and a transmitted beam 14. Specifically, the window 8 is used to divide the laser beam 12 passing through it into a reflected beam 13 (with a percentage less than 1%) and a transmitted beam 14 (with a percentage greater than 99%). The window 8 is located within the beam channel 11 and at its exit end. The spot detection unit 10 is used to detect the spot projected onto its detection end, specifically detecting the morphological information of the spot projected onto its detection end. The spot detection unit 10 is prior art and can be a conventional area scan camera. The reflection unit 9 is used to reflect the reflected beam 13 of the laser beam 12 projected onto the window plate 8 at a preset position to the detection end of the spot detection unit 10. The window plate 8 is configured to close the exit end of the beam channel 11.

[0050] Please see Figure 12 The mounting base 7 has a first mounting opening 16 on its side, and the reflector unit 9 is disposed within the first mounting opening 16. Please continue reading. Figure 10-12 The reflecting unit 9 includes a third housing 901 and a reflector assembly 902 disposed inside it. The third housing 901 is fixedly connected within the first mounting port 16. The spot detection unit 10 is fixedly connected within the third housing 901. The third housing 901 has a light inlet corresponding to the first mounting port 16 and a light outlet 903 corresponding to the detection end of the spot detection unit 10. The reflector assembly 902 is configured to reflect the reflected beam 13 of the laser beam 12 projected at a preset position to the detection end of the spot detection unit 10. Please refer to [link to relevant documentation]. Figure 10In addition, the mounting base 7 is provided with a vent 24. After assembly, inert gas can be easily introduced into the mounting base 7 through the vent 24 to maintain the stability of the laser beam propagation medium. Specifically, the vent 24 is located at the annular flange 25 at the lower part of the mounting base 7. The inlet of the vent 24 is located on the upper surface of the flange 25, and the outlet of the vent 24 is located inside the mounting base 7.

[0051] Please continue reading. Figure 10 and Figure 11 Specifically, the reflector assembly 902 includes a first reflector 9021, a second reflector 9022, and a third reflector 9023. The first and second reflectors 9021 and 9022 are arranged in parallel. The reflected beam 13 of the laser beam 12 projected at a preset position is reflected by the first and second reflectors 9021 and then onto the third reflector 9023. The third reflector 9023 is configured to reflect the reflected beam 13 projected onto it to the detection end. The path length of the reflected beam 13 to the detection end of the spot detection unit 10 is equal to the path length of the transmitted beam 14 to the printing plane. More specifically, a second mirror mount 904 is fixedly connected inside the third housing 901, and the third reflector 9023 is fixedly connected to the second mirror mount 904. The third reflector 9023 is tilted at a 40° angle downwards to the right. See details. Figure 11 The angle between the mirror surface of the third reflector 9023 and the horizontal plane is 40°. In actual use, the distance from the reflected beam 13 of the laser beam 12 projected onto the window plate 8 to the detection end of the spot detection unit 10 after being reflected by the reflector group 902 is equal to the distance from the transmitted beam 14 to the printing plane. Since the length of the reflected beam 13 is the same as the length of the transmitted beam 14, it is necessary to reflect the shape information of the spot transmitted by the transmitted beam 14 in the printing area. The path of the reflected beam 13 is longer, resulting in a longer length of the reflection unit 9. Since the first reflector 9021 and the second reflector 9022 are parallel to each other, the reflected beam 13 can be reflected multiple times between the first reflector 9021 and the second reflector 9022, thereby meeting the path length requirement of the reflected beam 13 and reducing the overall length of the reflection unit 9. In order to further prevent the high-energy reflected beam 13 from causing heat to the spot detection unit 10, preferably, an attenuation filter 23 is provided between the third reflector 9023 and the detection end of the spot detection unit 10.

[0052] Please continue reading. Figure 10Since the laser beam 12 is projected onto the window 8 from above, in order to ensure that the reflected beam 13 can be reflected onto the first reflector 9021 with a small angle to the vertical direction, the first reflector 9021 is preferably positioned above the second reflector 9022. The first reflector 9021 is closer to the entrance end of the beam channel 11, and the second reflector 9022 is closer to the exit end of the beam channel 11. The length of the first reflector 9021 extending into the beam channel 11 is greater than the length of the second reflector 9022 extending into the beam channel 11. Because the first reflector 9021 has a longer length extending into the beam channel 11, it can receive the reflected beam 13 closer to the direction perpendicular to the window 8, thus reducing the space occupied by the reflector assembly 902 inside the beam channel 11.

[0053] Please see Figure 13 The mounting base 7 has a third cooling medium channel 15 inside, with both the inlet and outlet of the third cooling medium channel 15 located on the outside of the mounting base 7. To improve the overall heat dissipation efficiency of the mounting base 7, the third cooling medium channel 15 is arranged in a tortuous shape along the circumference of the mounting base 7 to increase the heat exchange area of ​​the cooling medium.

[0054] During operation, several dynamic focusing scanning systems are used simultaneously for scanning and printing. Each system is responsible for scanning and printing a corresponding area, and each system is equipped with a laser. A laser beam 12 is emitted from the laser and travels along a path through a laser collimator 22, a dichroic mirror 1, and a beam zoom unit 2 before reaching a galvanometer unit 3. The beam zoom unit 2 focuses the laser beam 12, and the galvanometer unit 3 adjusts the position of the reflected laser beam 12 onto the printing plane, which is located within the forming chamber. The image of the printed part on the printing plane is reflected by the galvanometer unit 3 and the dichroic mirror 1 to the detection end of the vision inspection unit 4. To ensure the vision inspection unit 4 can recognize a clear image, a light source is provided within the forming chamber for illumination. The image acquired by the vision inspection unit 4 can identify whether the printed part deviates from the preset printing position, and any misalignments can be detected, allowing for real-time monitoring of misalignments during the printing process. Based on the information about misalignment, before scanning and printing the next layer, the scanning path of the laser beam 12 on the printing plane is adjusted by the galvanometer unit 3 to correct the misalignment. During the printing process, the galvanometer unit 3 adjusts the position of the laser beam 12 reflected onto the printing plane, thus scanning along a preset path. During scanning, the galvanometer unit 3 reflects the images of the currently scanned area and adjacent already scanned areas onto the dichroic mirror 1, which then reflects them to the detection end of the vision detection unit 4, allowing real-time acquisition of the forming status of the printed part along the scanning path. During the scanning and printing process, as the laser beam 12 is reflected onto the printing plane by the galvanometer unit 3, it first enters the beam channel 11, and then is split into a reflected beam 13 and a transmitted beam 14 by the window 8. The transmitted beam 14 reaches the printing area for scanning and printing. When the laser beam 12 is projected onto a preset position on the window plate 8, the reflected beam 13 is reflected by the reflection unit 9 to the detection end of the spot detection unit 10. The detection end of the detection unit identifies the spot, thereby obtaining the shape information of the spot. Since the transmitted beam 14 can still perform printing while the spot of the reflected beam 13 is being detected, the spot detection can be performed during the printing process, allowing for online detection. Furthermore, because the energy of the reflected beam 13 is low, it is less likely to damage the spot detection unit 10 during detection, resulting in a low safety risk. The heat generated by the reflected beam 13 is also low, resulting in a lower operating temperature for the spot detection unit 10, which helps ensure the operational stability and lifespan of the spot detection unit 10.In addition, by using the information such as the size and shape of the light spot detected by the light spot detection unit 10, it can be determined whether the focal length of the laser beam 12 deviates from the printing plane. If it deviates from the printing plane, the distance between the diverging mirror 202 and the focusing mirror group 201 can be adjusted by adjusting the linear drive mechanism 203, thereby adjusting the focal length of the laser beam 12 so that the light spot working on the printing plane can be adjusted to the required size.

[0055] It should be noted that words indicating direction in this article, such as "up" and "down," are all in the format of "upper" and "lower." Figure 1 The direction setting is for ease of description only and has no other specific meaning.

[0056] It should also be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or apparatus comprising a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or apparatus that includes the aforementioned element.

[0057] This article uses specific examples to illustrate the principles and implementation methods of this utility model. The descriptions of the above embodiments are only for the purpose of helping to understand the core ideas of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made to this utility model without departing from the principles of this utility model, and these improvements and modifications also fall within the protection scope of the claims of this utility model.

Claims

1. A high-speed dynamic focusing laser scanning system, characterized in that, It includes a dichroic mirror (1), a beam zoom unit (2) and a galvanometer unit (3) arranged sequentially on the path of the laser beam (12), and a visual detection unit (4) located outside the path; The beam zoom unit (2) is configured to focus the laser beam (12) and adjust the focal length of the laser beam (12); The galvanometer unit (3) is configured to reflect the laser beam (12) onto the printing plane and to adjust the planar position of the laser beam (12) reflected onto the printing plane; The dichroic mirror (1) is configured to allow the laser beam (12) to pass through; The detection end of the visual inspection unit (4) is configured to acquire an image of the printed part formed on the printing plane through the dichroic mirror (1) and the galvanometer unit (3).

2. The high-speed dynamic focusing laser scanning system according to claim 1, characterized in that, The beam zoom unit (2) includes a focusing lens group (201), a diverging lens (202), and a linear drive mechanism (203). The diverging lens (202) is fixed to the working end of the linear drive mechanism (203). The linear drive mechanism (203) is used to adjust the distance between the diverging lens (202) and the focusing lens group (201), thereby adjusting the focal length of the laser beam (12).

3. The high-speed dynamic focusing laser scanning system according to claim 2, characterized in that, The beam zoom unit (2) also includes a first housing (204), the focusing lens group (201), the diverging lens (202) and the linear drive mechanism (203) are all fixedly installed in the first housing (204), and the first housing (204) has a first light hole (205) at both ends for the laser beam (12) to pass through.

4. The high-speed dynamic focusing laser scanning system according to claim 3, characterized in that, The first housing (204) is provided with a heat exchange plate (206), and the heat exchange plate (206) is provided with a second optical hole (207) for the laser beam (12) to pass through. The heat exchange plate (206) is provided with two first cooling medium channels (208), and the first end of the first cooling medium channel (208) is connected to a medium interface (209). The medium interface (209) extends to the outside of the first housing (204). The first housing (204) is provided with a second cooling medium channel, and the inlet and outlet of the second cooling medium channel are respectively connected to the second ends of the two first cooling medium channels (208).

5. The high-speed dynamic focusing laser scanning system according to claim 3, characterized in that, It also includes a second housing (5), which is fixedly connected to the front end of the first housing (204). Both ends of the second housing (5) are provided with third light holes (6) for the laser beam (12) to pass through. The detection end of the visual detection unit (4) is located inside the second housing (5).

6. A high-speed dynamic focusing laser scanning system according to any one of claims 2-5, characterized in that, It also includes a spot detection component disposed at one end of the galvanometer unit (3) from which light is emitted. The spot detection component includes a mounting base (7), a window (8), a spot detection unit (10), and a reflection unit (9). The mounting base (7) is provided with a beam channel (11). The window (8) is used to divide the laser beam (12) projected onto it into a reflected beam (13) and a transmitted beam (14). The window (8) is disposed in the beam channel (11) and located at the exit end of the beam channel (11). The spot detection unit (10) is used to detect the spot projected onto its detection end. The reflection unit (9) is used to reflect the reflected beam (13) of the laser beam (12) projected onto the window (8) at a preset position to the detection end of the spot detection unit (10).

7. A high-speed dynamic focusing laser scanning system according to claim 6, characterized in that, The window (8) is configured to close the exit end of the beam channel (11).

8. The high-speed dynamic focusing laser scanning system according to claim 6, characterized in that, The mounting base (7) is provided with a third cooling medium channel (15) inside, and the inlet and outlet of the third cooling medium channel (15) are both opened on the outside of the mounting base (7).

9. A high-speed dynamic focusing laser scanning system according to claim 6, characterized in that, The mounting base (7) has a first mounting port (16) on its side. The reflecting unit (9) is disposed in the first mounting port (16). The reflecting unit (9) includes a third housing (901) and a reflector group (902) disposed inside it. The third housing (901) is fixedly connected in the first mounting port (16). The spot detection unit (10) is fixedly connected in the third housing (901). The third housing (901) has a light inlet corresponding to the first mounting port (16) and a light outlet (903) corresponding to the detection end of the spot detection unit (10). The reflector group (902) is configured to reflect the reflected beam (13) of the laser beam (12) projected at the preset position to the detection end of the spot detection unit (10).

10. A high-speed dynamic focusing laser scanning system according to claim 9, characterized in that, The reflector group (902) includes a first reflector (9021), a second reflector (9022), and a third reflector (9023). The first reflector (9021) and the second reflector (9022) are arranged in parallel. The reflected beam (13) of the laser beam (12) projected at the preset position is reflected by the first reflector (9021) and the second reflector (9022) and then reflected onto the third reflector (9023). The third reflector (9023) is configured to reflect the reflected beam (13) projected onto it to the detection end of the spot detection unit (10).

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