Light spot switching device for LPBF forming and light path system

Abstract

The utility model relates to the technical field of laser additive manufacturing, in particular to a light spot switching device for LPBF forming and a light path system. The light spot switching device comprises a shell, a light beam shaping unit and a first driving unit. Wherein the shell is provided with a light inlet and a light outlet which are used for forming a laser path; the light beam shaping unit is movably arranged in the shell, and the light beam shaping unit is used for shaping a light spot of the light beam into a linear light spot; when the light beam shaping unit is located at the first working position, the input end of the light beam shaping unit corresponds to the light inlet, and the output end corresponds to the light outlet; and when the light beam shaping unit is located at the second working position, the light beam shaping unit is located outside the laser path. The light beam shaping unit is driven by the first driving unit and is switched between the first working position and the second working position, so that the circular light spot and the linear light spot are switched to carry out printing work of additive manufacturing, and the printing processing efficiency of additive manufacturing is effectively improved.

Description

Technical Field

[0001] This utility model relates to the field of laser additive manufacturing technology, specifically to a spot switching device and optical path system for LPBF forming. Background Technology

[0002] Laser powder bed fusion (LPBF) is an important branch of laser additive manufacturing (AM). Based on the principle of layer-by-layer manufacturing, LPBF technology can use software to slice a 3D model of a part into layers, and then use a focused laser beam to selectively fuse powder particles layer by layer to directly obtain high-performance, high-density metal parts. Traditionally, additive manufacturing using LPBF employs a circular laser spot for printing.

[0003] However, traditional circular laser spot additive manufacturing technology has a relatively low single-pass processing width, which can only reach a size comparable to the diameter of the laser spot. Because the shapes of each layer vary during the printing process, some areas requiring printing are narrower, making circular laser spot printing more suitable; while other areas require printing wider, necessitating multiple repeated sweeps with a circular laser spot to complete a single layer, thus significantly limiting the processing efficiency of laser additive manufacturing. Utility Model Content

[0004] To address the aforementioned deficiencies, the technical problem to be solved by this utility model is to provide a spot switching device and optical path system for LPBF forming. This spot switching device can switch the laser to a line spot when needed, thereby increasing the processing width per pass and improving the processing efficiency of additive manufacturing.

[0005] The above-mentioned technical objective of this utility model is achieved through the following technical solution:

[0006] Firstly, a spot switching device for LPBF forming is provided, including:

[0007] The housing is provided with an inlet and an outlet for forming a laser path;

[0008] A beam shaping unit is movably disposed within the housing. The beam shaping unit is used to shape the spot of the light beam into a linear spot. When the beam shaping unit is in the first working position, its input end corresponds to the light inlet and its output end corresponds to the light outlet. When the beam shaping unit is in the second working position, the beam shaping unit is located outside the laser path.

[0009] A first driving unit is disposed within the housing, and the first driving unit is used to drive the beam shaping unit to switch between the first working position and the second working position.

[0010] By adopting the above scheme, during use, the first driving unit drives the beam shaping unit to the first working position. After the laser beam passes through the beam shaping unit, the beam spot is shaped into a linear spot. Additive manufacturing is performed using this linear spot, increasing the width of a single processing pass, thereby reducing the number of scans and improving processing efficiency. For the outline portion to be scanned and printed, and the portion that cannot be scanned and printed using the linear spot, the first driving unit moves the beam shaping unit to the second working position. At this time, the beam shaping unit leaves the laser path. The laser beam passes directly through the laser path, and the beam spot is circular. The beam shaping unit switches between the first and second working positions, thereby switching between circular and linear spots for additive manufacturing printing, effectively improving the printing efficiency of additive manufacturing. Furthermore, the housing provides a space to separate the beam shaping unit from the outside, preventing external environmental influences on the beam shaping unit.

[0011] Preferably, the beam shaping unit is disposed on the working end of the first driving unit and configured to rotate relative to the working end of the first driving unit. When scanning and printing in the printing area using a line spot, the required scanning width of the printing area may be smaller than the length of the line spot. For printing areas where the required scanning width is smaller than the length of the line spot, or for other areas with arc-shaped contours, the angle of the line spot can be adjusted by rotating the beam shaping unit, thereby adjusting the scanning width of the line spot on the printing area.

[0012] Preferably, the first drive unit includes a linear motor, a fixed base, a movable base, and a fixed sleeve. The movable base is slidably connected to the fixed base, the linear motor is mounted on the fixed base, and the working end of the linear motor is connected to the movable base. The fixed sleeve is fixedly connected to the movable base, and the beam shaping unit is rotatably mounted inside the fixed sleeve. Because the beam shaping unit is rotatably mounted inside the fixed sleeve, the stability of the beam shaping unit's rotation is improved, and the beam shaping unit is also protected.

[0013] Preferably, the fixed base is provided with a first mounting groove, and the movable base includes a movable block and a connecting member connected to each other. The movable block is slidably connected within the first mounting groove, and the fixed sleeve is fixedly connected to the connecting member. Because the movable block is slidably connected within the first mounting groove, the overall structure is more compact and saves installation space.

[0014] Preferably, the stator of the linear motor is disposed in the first mounting slot, and the movable block has a second mounting slot on the side facing the first mounting slot, with the mover of the linear motor disposed in the second mounting slot. Because the mover and stator of the linear motor are respectively disposed in the corresponding first and second mounting slots, the overall structure is more compact, and the overall size of the housing can be made smaller.

[0015] Preferably, the movable block and the fixed base are connected by a guide rail pair. The guide rail pair ensures the stability of the relative sliding between the movable block and the fixed base, thereby improving the stability of the beam shaping unit when switching between the first working position and the second working position.

[0016] Preferably, the beam shaping unit includes a lens sleeve and an optical lens assembly. The lens sleeve is rotatably connected within a fixed sleeve, and the optical lens assembly is disposed within the lens sleeve. The optical lens assembly is used to shape the laser beam spot into a linear spot. The optical lens assembly is a precision component, and the lens sleeve protects it. Furthermore, since the linear spot is shaped using the optical lens assembly, which has excellent light-guiding properties, the laser beam experiences minimal energy loss as it passes through, thus ensuring the energy efficiency of the laser beam.

[0017] Preferably, a second driving unit is also included, which is disposed within the fixed sleeve and is used to drive the beam shaping unit to rotate. The second driving unit facilitates the rotation of the beam shaping unit, and because it is located inside the fixed sleeve, it achieves high space utilization and a more compact overall structure.

[0018] Preferably, the second drive unit includes a rotary voice coil motor and a positioning sleeve. The positioning sleeve is fitted onto the lens sleeve, the mover of the voice coil motor is fixed on the outside of the positioning sleeve, and the stator of the voice coil motor is fixed on the inside of the positioning sleeve. This makes the second drive unit tightly integrated with adjacent components, further making the structure more compact.

[0019] Secondly, this utility model also provides an optical path system, including the above-mentioned spot switching device for LPBF.

[0020] In summary, the spot switching device for LPBF forming provided by this utility model has at least the following characteristics:

[0021] Beneficial effects:

[0022] 1. The beam shaping unit switches between a first working position and a second working position, thereby switching between circular and linear beam spots, which effectively improves the printing efficiency of additive manufacturing.

[0023] 2. Since the linear light spot is shaped by an optical mirror assembly, which has good light guiding properties, the laser beam experiences minimal energy loss when passing through the optical mirror assembly, thus ensuring the energy efficiency of the laser beam. Attached Figure Description

[0024] 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.

[0025] Figure 1 This is a three-dimensional structural diagram of the light spot switching device of this utility model from the right-hand perspective;

[0026] Figure 2 This is a three-dimensional structural diagram of the light spot switching device of this utility model from the left-hand perspective;

[0027] Figure 3 This is a three-dimensional structural diagram of the light spot switching device of this utility model from the right-hand perspective (the cover is hidden);

[0028] Figure 4 This is a right view of the light spot switching device of this utility model (the cover is hidden);

[0029] Figure 5 This is a three-dimensional structural diagram of the first driving unit and the beam shaping unit of this utility model from the right-side view.

[0030] Figure 6 This is a three-dimensional structural diagram of the first driving unit and beam shaping unit of this utility model from the left-hand perspective.

[0031] Figure 7 This is an exploded view of the first drive unit of this utility model from the left side.

[0032] Figure 8 This is an exploded view of the first drive unit of this utility model from the right side.

[0033] Figure 9 This is an exploded schematic diagram of the beam shaping unit of this utility model from an upward viewing angle;

[0034] Figure 10 This is a three-dimensional structural diagram of the optical path system of this utility model.

[0035] The reference numerals in the attached drawings include: housing 1, bottom shell 101, cover 102, light inlet 103, light outlet 104, beam shaping unit 2, lens sleeve 201, first connecting sleeve 2011, second connecting sleeve 2012, first slot 2013, optical lens group 202, bearing 203, first drive unit 3, fixed base 301, first mounting slot 302, moving base 303, movable block 3031, second mounting slot 3032, third mounting slot 3033, connector 3034, fixed sleeve 304, guide rail pair 305, end cap 306, through hole 307, positioning sleeve 4, laser galvanometer device 5, and laser collimator 6. Detailed Implementation

[0036] 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 1-10 The present invention will be further described in detail below with reference to specific embodiments.

[0037] Please see Figure 1-9 The light spot switching device for LPBF forming provided in this embodiment includes: a housing 1, a beam shaping unit 2, and a first driving unit 3. The housing 1 has a light inlet 103 and a light outlet 104 for forming a laser path. Specifically, the housing 1 includes a bottom shell 101 and a cover 102. The bottom shell 101 is a groove-shaped opening on the right side, and the cover 102 is detachably connected to the opening of the bottom shell 101 and closes the opening. The light inlet 103 is located on the cover 102, and the light outlet 104 is located on the left side of the bottom shell 101. The light inlet 103 and the light outlet 104 correspond to each other, and both the light inlet 103 and the light outlet 104 are circular holes. The beam shaping unit 2 is movably disposed within the housing 1 and is used to shape the light spot of the beam into a linear light spot. Specifically, the beam shaping unit 12 is used to shape the circular light spot of the beam into a linear light spot. When beam shaping unit 2 is in the first working position, its input end corresponds to the light inlet 103, and its output end corresponds to the light outlet 104. When beam shaping unit 2 is in the second working position, it is located outside the laser path. The first driving unit 3 is disposed inside the housing 1 and is used to drive beam shaping unit 2 to switch between the first and second working positions.

[0038] By adopting the above scheme, during use, the first driving unit 3 drives the beam shaping unit 2 to the first working position. After the laser beam passes through the beam shaping unit 2, the circular spot of the beam is shaped into a linear spot. Additive manufacturing using a linear spot increases the width of a single processing pass, thereby reducing the number of scans and improving processing efficiency. For the outline portion to be scanned and printed, and the portion that cannot be scanned and printed by the linear spot, the first driving unit 3 drives the beam shaping unit 2 to the second working position. At this time, the beam shaping unit 2 leaves the laser path. The laser beam passes directly through the laser path, and the spot of the beam is circular. The beam shaping unit 2 switches between the first and second working positions, thereby switching between a circular spot and a linear spot for additive manufacturing printing, effectively improving the printing efficiency of additive manufacturing. Furthermore, the housing 1 provides a space separated from the external environment for the beam shaping unit 2, preventing external environmental influences on the beam shaping unit 2.

[0039] Please continue reading, 5 and... Figure 9 Since the width of the beam beam required for scanning the printing area may be smaller than the length of the beam beam when scanning the printing area using a line spot, it is preferable that the beam shaping unit 2 is disposed on the working end of the first driving unit 3 and configured to rotate relative to the working end of the first driving unit 3. The first driving unit 3 can drive the beam shaping unit 2 to switch between a first working position and a second working position via its working end. Since the beam shaping unit 2 can rotate relative to the working end of the first driving unit 3, for printing areas where the required scanning width is smaller than the length of the beam beam, or for other areas with arc-shaped contours, the angle of the beam beam can be adjusted by rotating the beam shaping unit 2, thereby adjusting the width of the beam beam scanning along the scanning path on the printing area.

[0040] Please continue reading. Figure 4-8 Preferably, the first drive unit 3 includes a linear motor, a fixed base 301, a movable base 303, and a fixed sleeve 304. The movable base 303 is slidably connected to the fixed base 301, the linear motor is mounted on the fixed base 301, the working end of the linear motor is connected to the movable base 303, the fixed sleeve 304 is fixedly connected to the movable base 303, and the beam shaping unit 2 is rotatably mounted inside the fixed sleeve 304.

[0041] Please see Figure 7 and Figure 8Preferably, the fixed base 301 is provided with a first mounting groove 302, which is specifically located on the right side of the fixed base 301. The movable base 303 includes a movable block 3031 and a connecting member 3034 connected to each other. The movable block 3031 is slidably connected within the first mounting groove 302. The fixed sleeve 304 is fixedly connected to the connecting member 3034. Specifically, the lower end of the connecting member 3034 is C-shaped to match the outer contour of the fixed sleeve 304, and the fixed sleeve 304 is connected to the connecting member 3034 by bolts.

[0042] Preferably, the stator of the linear motor is disposed within the first mounting groove 302, and the movable block 3031 has a second mounting groove 3032 on the side facing the first mounting groove 302. The mover of the linear motor is disposed within the second mounting groove 3032. Linear motors are existing technology, and the mover of the linear motor can drive the movable block 3031 to move linearly.

[0043] Preferably, the movable block 3031 and the fixed seat 301 are connected by a guide rail pair 305, which is existing technology. The guide rail pair 305 can specifically be a combination of a slider and a guide rail. In this embodiment, the guide rail pair 305 preferably adopts a rolling cross guide rail pair, that is, a cross roller guide rail. In this embodiment, the upper and lower sides of the movable block 3031 are respectively connected to the fixed seat 301 through a guide rail pair 305. Specifically, a third mounting groove 3033 is provided on both the upper and lower sides of the movable block 3031. The guide rail pair 305 includes two guide rails that can slide relative to each other, one guide rail being fixedly installed in the corresponding third mounting groove 3033, and the other guide rail being fixedly installed in the first mounting groove 302.

[0044] Please continue reading. Figure 9 Preferably, the beam shaping unit 2 includes a lens sleeve 201 and an optical lens group 202. The lens sleeve 201 is rotatably mounted within the fixed sleeve 304, and the optical lens group 202 is disposed within the lens sleeve 201. The optical lens group 202 is used to shape the beam spot into a linear beam spot. The optical lens group 202 is a combination of optical lenses. In this embodiment, a combination of two optical lenses is specifically used, which can shape the circular beam spot into a linear beam spot. The technique of shaping the circular beam spot into a linear beam spot using the optical lens group 202 is existing technology. Since the linear beam spot is shaped by the optical lens group 202, which has good light guiding properties, the laser beam experiences minimal energy loss when passing through it, thus ensuring the energy efficiency of the laser beam.

[0045] Please see Figure 9Preferably, the lens sleeve 201 includes a first connecting sleeve 2011 and a second connecting sleeve 2012, which are connected by bolts. The inner edge of the right end of the first connecting sleeve 2011 has a first slot 2013, and the inner edge of the left end of the second connecting sleeve 2012 has a second slot. The two optical lenses of the optical lens assembly 202 are respectively installed in the first slot 2013 and the second slot. The first driving unit 3 also includes an end cap 306, which has a through hole 307 for the laser beam to pass through. The end cap 306 is connected to the left end of the fixing sleeve 304 by bolts. Both the first connecting sleeve 2011 and the second connecting sleeve 2012 are connected to the fixing sleeve 304 by bearings 203, preferably ceramic bearings from the prior art.

[0046] Please see Figure 9 To facilitate the rotation of the beam shaping unit 2, a second driving unit is preferably included. This second driving unit is housed within the fixed sleeve 304 and is used to drive the beam shaping unit 2 to rotate. Specifically, the second driving unit includes a rotary voice coil motor and a positioning sleeve 4. The positioning sleeve 4 is fitted onto the lens sleeve 201, and the positioning sleeve 4 is fixedly connected to the lens sleeve 201. The mover of the voice coil motor is fixed to the outside of the positioning sleeve 4, and the stator of the voice coil motor is fixed to the inside of the fixed sleeve 304. Specifically, the positioning sleeve 4 is fixedly connected to the second connecting sleeve 2012. The rotary voice coil motor is existing technology. The rotary voice coil motor can drive the positioning sleeve 4 to rotate via its mover, thereby driving the lens sleeve 201 and the optical lens assembly 202 to rotate, thus adjusting the tilt angle of the linear light spot.

[0047] Because laser beams have high energy, they generate significant heat around them during use. To improve heat dissipation efficiency, the housing 1 is preferably made of aluminum alloy. Specifically, both the cover 102 and the bottom shell 101 are made of aluminum alloy. The excellent thermal conductivity of aluminum alloy improves heat dissipation efficiency.

[0048] Please see Figure 10Based on the same inventive concept, this utility model also provides an optical path system, which includes the aforementioned spot switching device for LPBF. Specifically, the optical path system further includes a laser galvanometer device 5 and a laser collimator 6. The LPBF spot switching device is fixedly installed on the right side of the laser galvanometer device 5, and the laser collimator 6 is fixedly installed on the right side of the LPBF spot switching device. During use, the laser beam passes through the laser collimator 6, then through the light inlet 103 and light outlet 104 of the LPBF spot switching device, and enters the laser galvanometer device 5. Finally, the laser beam scans and prints the printing area through the laser beam output end of the laser galvanometer device 5. Both the laser galvanometer device and the laser collimator are prior art. The laser galvanometer device includes an XY optical scanning head, an electronic drive amplifier, an optical reflecting mirror, and a computer controller. The signal provided by the computer controller drives the optical scanning head through the drive amplifier circuit, thereby controlling the deflection of the laser beam in the XY plane.

[0049] 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.

[0050] 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.

[0051] 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 spot switching device for LPBF forming, characterized in that, The application relates to a laser spot switching device for LPBF (laser powder bed fusion) forming. The laser spot switching device comprises a shell (1) provided with a light inlet (103) and a light outlet (104) for forming a laser channel; a light beam shaping unit (2) movably arranged in the shell (1), the light beam shaping unit (2) is used for shaping a light spot of a light beam into a linear light spot; when the light beam shaping unit (2) is located at a first working position, an input end of the light beam shaping unit (2) corresponds to the light inlet (103), and an output end of the light beam shaping unit (2) corresponds to the light outlet (104); when the light beam shaping unit (2) is located at a second working position, the light beam shaping unit (2) is located outside the laser channel; a first driving unit (3) arranged in the shell (1), the first driving unit (3) is used for driving the light beam shaping unit (2) to switch between the first working position and the second working position. The light beam shaping unit (2) is arranged on a working end of the first driving unit (3) and is configured to be capable of rotating relative to the working end of the first driving unit (3). The first driving unit (3) comprises a linear motor, a fixed seat (301), a moving seat (303) and a fixed sleeve (304), the moving seat (303) is slidably connected to the fixed seat (301), the linear motor is arranged on the fixed seat (301), a working end of the linear motor is connected to the moving seat (303), the fixed sleeve (304) is fixedly connected to the moving seat (303), and the light beam shaping unit (2) is rotatably arranged in the fixed sleeve (304).

2. The spot switching device for LPBF forming according to claim 1, characterized in that, A first mounting groove (302) is arranged on the fixed seat (301), the moving seat (303) comprises a movable block (3031) and a connecting piece (3034) connected to each other, the movable block (3031) is slidably connected in the first mounting groove (302), and the fixed sleeve (304) is fixedly connected to the connecting piece (3034).

3. The spot switching device for LPBF forming according to claim 2, characterized in that, A stator of the linear motor is arranged in the first mounting groove (302), a second mounting groove (3032) is formed in a side of the movable block (3031) facing the first mounting groove (302), and a rotor of the linear motor is arranged in the second mounting groove (3032).

4. The spot switching device for LPBF forming according to claim 3, characterized in that, The movable block (3031) and the fixed seat (301) are connected through a guide rail pair (305).

5. The spot switching device for LPBF forming according to claim 4, characterized in that, The light beam shaping unit (2) comprises a mirror sleeve (201) and an optical mirror group (202), the mirror sleeve (201) is rotatably connected in the fixed sleeve (304), the optical mirror group (202) is arranged in the mirror sleeve (201), and the optical mirror group (202) is used for shaping a light spot of a light beam into a linear light spot.

6. The spot switching device for LPBF forming according to claim 4, wherein, The application further comprises a second driving unit, the second driving unit is arranged in the fixed sleeve (304), and the second driving unit is used for driving the light beam shaping unit (2) to rotate.

7. The spot switching device for LPBF forming according to any one of claims 3-6, characterized in that, The second driving unit comprises a rotary voice coil motor and a positioning sleeve (4), the positioning sleeve (4) is sleeved on the mirror sleeve (201), a rotor of the voice coil motor is fixed to an outer side of the positioning sleeve (4), and a stator of the voice coil motor is fixed to an inner side of the fixed sleeve (304).

8. The spot switching device for LPBF forming according to claim 7, characterized in that, The application further provides a laser spot switching device for LPBF forming.

9. The spot switching device for LPBF forming according to claim 8, characterized in that, ​ 10. An optical path system, characterized by comprising: ​

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