Light spot detection device

Abstract

The utility model relates to the technical field of additive manufacturing, in particular to a light spot detection device. The detection device comprises a mounting base, a diaphragm, a light spot detection unit and a reflection unit. Wherein the mounting seat is provided with a light beam channel, the diaphragm is used for dividing a laser beam projected on the diaphragm into a reflected light beam and a transmitted light beam, and the diaphragm is arranged in the light beam channel. During use, when a laser beam is projected to a preset position on the diaphragm, 99% of the laser beam is transmitted to form a transmitted beam, and less than 1% of the remaining laser beam is reflected to form a reflected beam. Wherein the transmission light beam is used for carrying out printing work in a printing area; and the reflected light beam is reflected to the detection end of the light spot detection unit through the reflection unit, and the light spot is identified through the detection end of the detection unit, so that the form information of the light spot is obtained. And when the light spot of the reflected light beam is detected, the transmitted light beam can still be printed, so that the detection work of the light spot can be carried out on line.

Description

Technical Field

[0001] This utility model relates to the field of additive manufacturing technology, specifically to a spot detection device. Background Technology

[0002] Laser Powder Bed Fusion (LPBF) additive manufacturing is a technology that uses a focused laser beam to fuse loose powder along a designed path to form parts layer by layer. This technology has wide applications in aerospace, automotive, and medical fields. In the LPBF additive manufacturing process, measuring the high-energy laser spot is crucial to ensuring that the parameters of the high-energy laser spot are within the preset parameters.

[0003] In existing technologies, to determine whether the shape, size, or energy intensity of a high-energy laser spot meets requirements during operation, it is necessary to detect the high-energy laser spot. Currently, when obtaining parameters of a high-energy laser spot, the device for detecting the spot needs to be placed on a printing platform, allowing the laser to directly strike the detection device for detection.

[0004] While existing methods for detecting high-energy laser spots can obtain relatively accurate laser spot parameters, several problems exist during their use. First, because the spot detection equipment needs to be placed on a printing platform, performing spot detection during the printing process can disrupt the printing workflow, making online spot detection difficult. Second, due to the high energy of the high-energy laser beam, the spot detection equipment is easily damaged, posing a significant safety risk. Utility Model Content

[0005] To address the aforementioned deficiencies, the technical problem to be solved by this utility model is to provide a spot detection device that can perform spot detection during the printing process.

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

[0007] A spot detection device, comprising:

[0008] Mounting base, which has a beam channel;

[0009] A window is used to split the laser beam projected onto it into a reflected beam and a transmitted beam. The window is disposed in the beam channel and located at the exit end of the beam channel.

[0010] A spot detection unit is used to detect the spot of light projected onto its detection end;

[0011] The reflection unit is used to reflect the reflected beam of the laser beam projected onto a preset position on the window to the detection end.

[0012] By adopting the above scheme, during use, the laser beam enters the beam channel and is projected onto a preset position on the window. The laser beam is then split into a reflected beam and a transmitted beam by the window. 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 information such as its shape and size. Since printing can continue even while the reflected beam is being detected, spot detection can be performed during the printing process, meaning it can be done online. Furthermore, because the reflected laser beam has lower energy, it is less likely to damage the spot detection unit during detection, resulting in low safety risks. Additionally, the reflected beam generates less heat, leading to a lower operating temperature for the spot detection unit, which helps ensure its operational stability and lifespan.

[0013] 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, it separates the reflecting unit from the printing area, preventing mutual interference, and also serves as a sealing connection for the printing chamber.

[0014] Preferably, the mounting base has a mounting opening on its side, and the reflecting unit is disposed at the mounting opening. The fact that the reflecting unit is located at the mounting opening on the side of the mounting base makes it easier for the reflecting unit to receive the reflected light beam.

[0015] Preferably, the reflecting unit includes a housing and a mirror assembly disposed inside it. The housing is fixedly connected to the mounting port, and the light spot detection unit is fixedly connected to the housing. The housing has a light inlet corresponding to the mounting port and a light outlet corresponding to the detection end. The mirror assembly is configured to reflect the reflected beam of the laser beam projected at the preset position to the detection end. Because the mirror assembly is disposed inside the housing, the influence of the external environment on the mirror assembly is reduced.

[0016] Preferably, the reflector assembly 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 onto 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. Since the length of the reflected beam needs to be the same as the length of the transmitted beam to reflect information such as the shape and size of the light spot transmitted by the transmitted beam in the printing area, the path of the reflected beam is relatively long, resulting in a longer length of the reflective unit. 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 reflective unit.

[0017] Preferably, the first reflector is located near the entrance end of the beam channel, and the second reflector is located near the exit end of the beam channel. The length of the first reflector extending into the beam channel is greater than the length of the second reflector extending into the beam channel. Because the first reflector extends longer into the beam channel, it can receive reflected beams closer to the direction perpendicular to the window, thus reducing the space occupied by the reflector assembly within the beam channel.

[0018] Preferably, the reflecting unit further includes two pressure plates, which are respectively disposed corresponding to the first reflecting lens and the second reflecting lens. The pressure plates are connected to the housing by a number of locking bolts. The first reflecting lens is clamped between the corresponding pressure plate and the housing, and the second reflecting lens is clamped between the corresponding pressure plate and the housing. By fixing the corresponding first and second reflecting lenses to the housing through the pressure plates, the stability of the reflecting mirror assembly is enhanced.

[0019] Preferably, a spring is fitted onto the locking bolt, with one end of the spring abutting against the pressure plate and the other end abutting against the head of the locking bolt. Because of the spring on the locking bolt, the pressure plate maintains the clamping force on the corresponding first and second reflecting lenses. Simultaneously, due to the elasticity of the spring, over-tightening of the locking bolt during installation can prevent damage to the first and second lenses.

[0020] Preferably, the reflection unit further includes an attenuation filter disposed on the path of the reflected beam to the detection end. The attenuation filter reduces the energy of the reflected beam, thereby reducing the risk of damage to the spot detection unit.

[0021] Preferably, the mounting base has a cooling medium channel inside, with both the medium inlet and outlet of the cooling medium channel located on the outside of the mounting base. Since the laser beam generates significant heat to the surrounding environment during operation, introducing cooling medium into the cooling medium channel can reduce the temperature of the mounting base and its interior.

[0022] In summary, the light spot detection device provided by this utility model has at least the following beneficial effects:

[0023] 1. It can detect the shape, size and other information of the light spot online, making it more convenient to use.

[0024] 2. The safety risks of detecting light spots are lower. 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 diagram of the present invention from a top-down perspective;

[0027] Figure 2 This is a three-dimensional structural diagram of the present invention from a downward viewing angle;

[0028] Figure 3 This is the front view of this utility model;

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

[0030] Figure 5 yes Figure 4 An enlarged view of point a in the middle;

[0031] Figure 6 This is a three-dimensional structural diagram of the reflective unit in this utility model;

[0032] Figure 7 This is an exploded view of the reflective unit in this utility model;

[0033] Figure 8 This is a three-dimensional structural diagram of the mounting base in this utility model;

[0034] Figure 9 This is a perspective view of the mounting base in this utility model from a side view.

[0035] The reference numerals in the attached drawings include: mounting base 1, beam channel 2, window 3, spot detection unit 4, reflection unit 5, housing 501, light outlet 502, mirror assembly 503, first mirror 5031, second mirror 5032, third mirror 5033, pressure plate 504, locking bolt 505, spring 506, attenuation filter 507, mounting groove 508, threaded hole 509, positioning bolt 510, slot 511, clearance hole 512, through hole 513, mirror base 514, mounting port 6, cooling medium channel 7, medium inlet 8, medium outlet 9, flange 10, end cap 11, laser beam 12, reflected beam 13, transmitted beam 14. 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 1-9 The present invention will be further described in detail below with reference to specific embodiments.

[0037] Please see Figure 1-9 This embodiment provides a light spot detection device, including: a mounting base 1, a window 3, a light spot detection unit 4, and a reflection unit 5. The mounting base 1 has a beam channel 2, which is vertically arranged, with its upper end as the entrance and its lower end as the exit. The window 3 is used to divide the laser beam 12 projected onto it into a reflected beam 13 and a transmitted beam 14. The window 3 is disposed within the beam channel 2 and located at its exit. In this embodiment, to ensure high transmittance of the laser beam 12, the window 3 is preferably made of high-transmittance fused silica glass, as even with high-transmittance fused silica glass, less than 1% of the laser light is reflected, thus forming a low-energy reflected beam 13 and a high-energy transmitted beam 14. The light spot detection unit 4 is used to detect the light spot projected onto its detection end; specifically, the detection unit 4 is used to detect the shape of the light spot projected onto its detection end. The light spot detection unit 4 is a prior art device, specifically a pre-existing area array camera. The reflection unit 5 is used to reflect the reflected beam 13 of the laser beam 12 projected onto the window plate 3 at a preset position to the detection end.

[0038] By adopting the above scheme, during use, the laser beam 12 enters the beam channel 2. When the laser beam 12 is projected onto a preset position on the window 3, it is split into a reflected beam 13 and a transmitted beam 14 by the window 3. The transmitted beam 14 is used for printing in the printing area; the reflected beam 13 is reflected by the reflection unit 5 to the detection end of the spot detection unit 4, where the spot is identified to obtain information such as its shape and size. Since the transmitted beam 14 can still print while the spot of the reflected beam 13 is being detected, spot detection can be performed during the printing process, meaning spot detection can be done online. Furthermore, because the reflected beam 13 has low energy, it is less likely to damage the spot detection unit 4 during detection, resulting in low safety risk. Additionally, the heat generated by the reflected beam 13 is also low, resulting in a lower operating temperature for the spot detection unit 4, which helps ensure the stability and lifespan of the spot detection unit 4.

[0039] Please continue reading. Figure 2 and Figure 4 Preferably, the window 3 is configured to close the exit end of the beam channel 2. Specifically, the window 3 is a circular lens. The window 3 is fixed to the lower end of the mounting base 1 by the flange 10 and bolts. The edge of the window 3 is sandwiched between the flange 10 and the lower end face of the mounting base 1.

[0040] Please continue reading. Figure 8 Preferably, the mounting base 1 has a mounting opening 6 on its right side, and the reflecting unit 5 is disposed at the mounting opening 6. Since the laser beam 12 is input from the top of the mounting base 1, and during the printing process, the laser beam 12 is adjusted in angle by the galvanometer system to scan and print in the printing area, the range of motion of the laser beam 12 is a conical spatial range. To accommodate the range of motion of the laser beam 12 and reduce the amount of material used in manufacturing the mounting base 1, preferably, the mounting base 1 is trumpet-shaped with a small diameter at the top and a large diameter at the bottom.

[0041] Please see Figure 9 Preferably, the mounting base 1 has a cooling medium channel 7 inside, and the medium inlet 8 and medium outlet 9 of the cooling medium channel 7 are both located on the outside of the mounting base 1. In order to improve the overall heat dissipation efficiency of the mounting base 1, the cooling medium channel 7 is arranged in a tortuous shape along the circumference of the mounting base 1 to increase the heat exchange area of ​​the cooling medium.

[0042] Please continue reading. Figure 4 and Figure 5Preferably, the reflecting unit 5 includes a housing 501 and a reflector assembly 503 disposed inside it. The housing 501 is fixedly connected to the mounting port 6. The spot detection unit 4 is fixedly connected to the housing 501. The left side of the housing 501 has a light inlet corresponding to the mounting port 6, and the right side of the housing 501 has a light outlet 502 corresponding to the detection end. The reflector assembly 503 is configured to reflect the reflected beam 13 of the laser beam 12 projected at a preset position to the detection end. The spot detection unit 4 is fixedly connected to the right side of the housing 501. An end cap 11 is also fixedly connected to the right side of the housing 501, covering the spot detection unit 4.

[0043] Please continue reading. Figure 4 and Figure 5 Specifically, the reflector assembly 503 includes a first reflector 5031, a second reflector 5032, and a third reflector 5033. The first reflector 5031 and the second reflector 5032 are arranged in parallel. The reflected beam 13 of the laser beam 12 projected onto the preset position is reflected onto the third reflector 5033 after being reflected by the first and second reflectors 5031 and 5032. The third reflector 5033 is configured to reflect the reflected beam 13 projected onto it to the detection end. More specifically, a mirror base 514 is fixedly connected inside the housing 501, and the third reflector 5033 is fixedly connected to the mirror base 514. The reflector is tilted at 45° to the lower right. In actual use, the distance from which the reflected beam 13 of the laser beam 12 projected onto the preset position on the window plate 3 is reflected by the reflector assembly 503 to the detection end of the spot detection unit 4 is equal to the distance from the transmitted beam 14 to the printing working plane. Because the length of the reflected beam 13 is the same as the length of the transmitted beam 14, it is necessary to reflect information such as the shape and size of the light spot transmitted by the transmitted beam 14 in the printing area. The path of the reflected beam 13 is relatively long, resulting in a longer length of the reflecting unit 5. Since the first reflecting mirror 5031 and the second reflecting mirror 5032 are parallel to each other, the reflected beam 13 can be reflected multiple times between the reflection by the first reflecting mirror 5031 and the second reflecting mirror 5032, thereby meeting the path length requirement of the reflected beam 13 and reducing the overall length of the reflecting unit 5.

[0044] Please continue reading. Figure 4 , 57. Since the laser beam 12 is projected onto the window 3 from above, in order to ensure that the reflected beam 13 can be reflected onto the first reflector 5031 with a small angle to the vertical direction, preferably, the first reflector 5031 is positioned above the second reflector 5032. The first reflector 5031 is closer to the entrance end of the beam channel 2, and the second reflector 5032 is closer to the exit end of the beam channel 2. The length of the first reflector 5031 extending into the beam channel 2 is greater than the length of the second reflector 5032 extending into the beam channel 2. Because the first reflector 5031 extends longer into the beam channel 2, it can receive the reflected beam 13 closer to the direction perpendicular to the window 3, thereby reducing the space occupied by the reflector assembly 503 inside the beam channel 2.

[0045] Please continue reading. Figure 7 To facilitate the fixing of the reflecting mirrors, preferably, the reflecting unit 5 also includes two pressure plates 504. The two pressure plates 504 are respectively disposed corresponding to the first reflecting mirror 5031 and the second reflecting mirror 5032. The pressure plates 504 are connected to the housing 501 by a number of locking bolts 505. In this embodiment, preferably, the pressure plates 504 are connected to the housing 501 by four locking bolts 505. The housing 501 has through holes 513 for the threaded sections of the corresponding locking bolts 505 to pass through. Specifically, four through holes 513 are opened on the upper side and four through holes 513 are opened on the lower side of the housing 501. The first reflecting mirror 5031 is sandwiched between the corresponding pressure plate 504 and the housing 501, and the second reflecting mirror 5032 is sandwiched between the corresponding pressure plate 504 and the housing 501. The pressure plates 504 have a number of clearance holes 512 for the reflected beam 13 to be projected onto the corresponding first reflecting mirror 5031 and the second reflecting mirror 5032.

[0046] Please continue reading. Figure 7 Preferably, a spring 506 is fitted onto the locking bolt 505. One end of the spring 506 abuts against the pressure plate 504, and the other end abuts against the head of the locking bolt 505. Specifically, the pressure plate 504 has a slot 511 on the side facing the corresponding reflector. The first reflector 5031 and the second reflector 5032 are respectively installed in the corresponding slots 511. The end faces of the first reflector 5031 and the second reflector 5032 that abut against the housing 501 are located outside the corresponding slots 511, so that the housing 501 and the pressure plate 504 can clamp the corresponding reflectors. Because the locking bolt 505 is equipped with a spring 506, the spring 506 can maintain the clamping force of the pressure plate 504 on the corresponding first reflector 5031 and the second reflector 5032. At the same time, due to the elastic characteristics of the spring 506, over-tightening of the locking bolt 505 during installation can prevent damage to the first and second reflectors.

[0047] Please continue reading. Figure 5 Preferably, the reflecting unit 5 further includes an attenuating filter 507, which is disposed on the path from the reflected beam 13 to the detection end. Specifically, a mounting groove 508 is provided on the right side of the housing 501, which communicates with the light output hole, and the attenuating filter 507 is installed in the mounting groove 508. To facilitate fixing the attenuating filter 507, a threaded hole 509 is provided on the lower side of the housing 501, which communicates with the mounting groove 508. A positioning bolt 510 is threaded into the threaded hole 509, and the upper end of the positioning bolt 510 presses the attenuating filter 507 against the mounting groove 508, thereby fixing the attenuating filter 507 in the mounting groove 508.

[0048] 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.

[0049] 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.

[0050] 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 detection device, characterized in that, include: Mounting base (1), on which a beam channel (2) is provided; A window (3) is used to divide the laser beam (12) projected thereon into a reflected beam (13) and a transmitted beam (14). The window (3) is disposed in the beam channel (2) and located at the exit end of the beam channel (2). A light spot detection unit (4) is used to detect the light spot projected onto its detection end; The reflection unit (5) is used to reflect the reflected beam (13) of the laser beam (12) projected onto the window (3) at a preset position to the detection end.

2. The spot detection device according to claim 1, characterized in that, The window (3) is configured to close the exit end of the beam channel (2).

3. The spot detection device according to claim 1, characterized in that, The mounting base (1) has a mounting port (6) on its side, and the reflective unit (5) is located at the mounting port (6).

4. The spot detection device according to claim 3, characterized in that, The reflecting unit (5) includes a housing (501) and a reflector assembly (503) disposed inside it. The housing (501) is fixedly connected to the mounting port (6). The spot detection unit (4) is fixedly connected to the housing (501). The housing (501) has a light inlet corresponding to the mounting port (6) and a light outlet (502) corresponding to the detection end. The reflector assembly (503) is configured to reflect the reflected beam (13) of the laser beam (12) projected at the preset position to the detection end.

5. The spot detection device according to claim 4, characterized in that, The reflector group (503) includes a first reflector (5031), a second reflector (5032), and a third reflector (5033). The first reflector (5031) and the second reflector (5032) are arranged in parallel. The reflected beam (13) of the laser beam (12) projected at the preset position is reflected by the first reflector (5031) and the second reflector (5032) and then reflected onto the third reflector (5033). The third reflector (5033) is configured to reflect the reflected beam (13) projected onto it to the detection end.

6. The spot detection device according to claim 5, characterized in that, The first reflector (5031) is close to the entrance end of the beam channel (2), and the second reflector (5032) is close to the exit end of the beam channel (2). The length of the first reflector (5031) extending into the beam channel (2) is greater than the length of the second reflector (5032) extending into the beam channel (2).

7. A spot detection device according to any one of claims 4-6, characterized in that, The reflective unit (5) further includes two pressure plates (504), which are respectively arranged corresponding to the first reflector (5031) and the second reflector (5032). The pressure plates (504) are connected to the housing (501) by a number of locking bolts (505). The first reflector (5031) is sandwiched between the corresponding pressure plate (504) and the housing (501), and the second reflector (5032) is sandwiched between the corresponding pressure plate (504) and the housing (501).

8. The spot detection device according to claim 7, characterized in that, A spring (506) is fitted on the locking bolt (505). One end of the spring (506) abuts against the pressure plate (504), and the other end abuts against the head of the locking bolt (505).

9. The light spot detection device according to claim 4, characterized in that, The reflection unit (5) further includes an attenuation filter (507), which is disposed on the path from the reflected beam (13) to the detection end.

10. The spot detection device according to claim 1, characterized in that, The mounting base (1) is provided with a cooling medium channel (7) inside, and the medium inlet (8) and medium outlet (9) of the cooling medium channel (7) are both opened on the outside of the mounting base (1).

Images