Independent flow field device for avoiding lens and powder spreading surface pollution and 3D printer
The independent flow field device's blowing and suction design solves the problem of black smoke pollution in 3D metal printing, achieving cleaning of the lens and powder-coated surface and improving printing results.
Patent Information
- Application Number
- CN202423161398.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-20
- Publication Date
- 2025-11-18
- Estimated Expiration
- 2034-12-20
AI Technical Summary
During 3D metal printing, the black smoke generated by laser melting causes contamination of the lens and powder surface, affecting the printing quality.
An independent flow field device is adopted, including an air blowing section and an air suction section. The air blowing section blows gas onto the powder-coated surface and the lens, and the black smoke is blown to the air suction section and sucked away. An external fan is used to suck out the black smoke to avoid pollution.
It effectively reduces black smoke contamination of the lens and powder-coated surface, improving print quality and efficiency.
Smart Images
Figure CN223557266U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of metal 3D printing, and in particular to an independent flow field device and 3D printer for avoiding contamination of lenses and powder surfaces. Background Technology
[0002] A 3D metal printer is a scientific instrument used in basic sciences of physics, engineering and technology, and mechanical engineering. It uses laser melting technology to melt metal powder to form functional solid parts. It can be used to print high-throughput metal materials. It is a fully digital rapid prototyping manufacturing process that directly produces high-density metal parts based on the interface data of each layer in 3D CAD. The thickness of the molten metal layer ranges from 20 micrometers to 100 micrometers, enabling rapid metal prototyping.
[0003] When a 3D printer manufactures parts, it first needs to lay down metal powder in the forming cylinder of the forming chamber. A laser melting device is then positioned in the forming chamber and aligns with the metal powder in the forming cylinder to melt it using a laser. The metal then solidifies and forms the final product. However, during the laser melting process, black smoke, or black dust, is generated at the contact points between the laser and the surface of the laid metal powder. This black smoke contaminates the powder-laying surface and gradually permeates the forming chamber. Furthermore, the black smoke particles adhere to the lenses of the laser melting device, causing contamination. Utility Model Content
[0004] To address the issue of black smoke generated during laser melting contaminating the powder-coated surface and lens, this application provides an independent flow field device and 3D printer for preventing contamination of the lens and powder-coated surface.
[0005] The independent flow field device and 3D printer provided in this application for avoiding contamination of the lens and powder surface adopt the following technical solution:
[0006] In a first aspect, this application provides an independent flow field device for avoiding contamination of the lens and powder surface:
[0007] An independent flow field device for avoiding contamination of lens and powder surface includes an air blowing section and an air suction section, which are disposed opposite to each other on both sides of a forming chamber.
[0008] The air blowing section includes an air blowing pipe, a pressure equalization chamber, and an air blowing head. One end of the pressure equalization chamber is connected to the air blowing pipe, and the other end of the pressure equalization chamber is connected to the air blowing head. The pressure equalization chamber and the air blowing head are both fixedly installed on the side wall of the molding chamber. The pressure equalization chamber is located on the outside of the molding chamber, and the air blowing head is located on the inside of the molding chamber. The connection between the pressure equalization chamber and the air blowing head penetrates through the side wall of the molding chamber. The air blowing head is oriented towards the powder-coated surface and the lens.
[0009] The air intake section includes an air intake pipe, an air intake chamber, and an air intake head. One end of the air intake chamber is connected to the air intake pipe, and the other end of the air intake chamber is connected to the air intake head. Both the air intake chamber and the air intake head are fixedly installed on the side wall of the molding chamber, with the air intake chamber located outside the molding chamber and the air intake head located inside the molding chamber. The connection between the air intake chamber and the air intake head penetrates the side wall of the molding chamber.
[0010] By adopting the above technical solution, when laser melting is performed in the molding chamber, gas is introduced into the blowing pipe. After passing through the suction chamber, the gas is blown out from the suction head. Since the blowing head is set towards the powder-coated surface and the lens, the black smoke generated on the powder-coated surface and the black smoke that escaped to the lens are blown to the side where the suction head is located. The suction pipe can be drawn out by an external fan, thereby drawing out the black smoke from the suction head, suction chamber and suction pipe in sequence, reducing the pollution of the powder-coated surface and the lens caused by the black smoke.
[0011] Optionally, the equalizing chamber includes a first chamber and a second chamber, and the blowing head includes a first head body and a second head body. The first chamber and the first head body are connected to each other, and the second chamber and the second head body are connected to each other. The first head body is positioned towards the lens, and the second head body is positioned towards the powder-coated surface.
[0012] The air blowing pipe is connected to the first compartment and the second compartment via a first branch pipe and a second branch pipe, respectively.
[0013] By employing the above-mentioned technical solutions, air is blown onto the powder-coated surface and the lens respectively, which helps to improve the accuracy and efficiency of blowing away black smoke.
[0014] Optionally, the equalizing chamber is arranged to gradually expand from the air blowing pipe toward the air blowing head. The air blowing head includes an air inlet rectangular frame and a speed-increasing plate fixedly connected to the air inlet rectangular frame. The speed-increasing plate has multiple speed-increasing holes. The opening at one end of the air inlet rectangular frame is connected to the equalizing chamber, and the opening at the other end of the air inlet rectangular frame is connected to the speed-increasing holes.
[0015] By adopting the above technical solution, the gas in the blowing pipe sequentially enters the equalizing chamber and the air inlet rectangular frame, and then is blown out through the speed-increasing orifice. The equalizing chamber is gradually widened from the blowing pipe toward the blowing head, which allows the gas in the blowing pipe to gradually diffuse in the equalizing chamber, increasing the gas blowing area; the speed-increasing orifice accelerates the blown gas, making it easier to blow away the black smoke.
[0016] Optionally, multiple pressure equalization orifice plates are spaced apart along the gradually expanding direction of the pressure equalization chamber.
[0017] By adopting the above technical solution, multiple pressure equalization orifice plates can diffuse the gas flowing through the pressure equalization chamber step by step, improve the diffusion effect, and thus improve the pressure equalization effect. This allows the gas in the pressure equalization chamber to enter the air intake rectangular frame over a large area, preventing the gas in the pressure equalization chamber from concentrating and entering the air intake rectangular frame from the middle, thereby avoiding the situation where the gas is blown out in a concentrated manner and only a local black smoke is blown away.
[0018] Optionally, multiple mounting protrusions are fixedly connected to both sides of the equalizing orifice plate in the width direction, and mounting grooves are provided on the top and bottom walls of the equalizing chamber for the mounting protrusions to be inserted into.
[0019] By adopting the above technical solution, the installation of the pressure equalization orifice plate is facilitated.
[0020] Optionally, the thickness of the equalizing chamber is set to gradually decrease from the direction of the air blowing pipe toward the air blowing head.
[0021] By adopting the above technical solution, it is helpful to pressurize and accelerate the gas in the equalization chamber.
[0022] Optionally, the speed-increasing orifice is arranged in a triangular shape.
[0023] By adopting the above technical solution, for the same area and number of speed-increasing orifices, if circular orifices are used, the wind speed will be too high, and they will not be able to effectively blow away the black smoke; if square orifices are used, although they have a better effect than circular orifices, the processing cost of square orifices is high. The speed-increasing orifices in this application are arranged in a triangular shape, which facilitates reasonable control of the blowing wind speed and saves processing costs.
[0024] Optionally, the length of the first head body is less than the length of the second head body, and the size of the speed-increasing hole on the first head body is greater than the size of the speed-increasing hole on the second head body; the distance between the lowest point of the speed-increasing hole on the first head body and the bottom surface of the speed-increasing plate on the first head body is a first distance, and the distance between the lowest point of the speed-increasing hole on the second head body and the bottom surface of the speed-increasing plate on the second head body is a second distance, and the second distance is greater than the first distance.
[0025] By adopting the above technical solution, the length of the first head body is shorter than that of the second head body because the air blown out by the second head body needs to cover the entire printing arc surface of the powder-coated surface, so it is longer. The first head body is mainly for cleaning, so it does not need to be longer.
[0026] The size of the speed-increasing hole on the first head body is larger than that on the second head body because the air blown out by the second head body acts on the lens and the powder-coated surface. The powder-coated surface is where black smoke is emitted, and there is a lot of black smoke. Therefore, the size of the speed-increasing hole at this location is smaller than that at the lens. In other words, the wind speed acting on the powder-coated surface is greater than the wind speed at the lens.
[0027] Additionally, the printed curved surface, i.e. the powder-coated surface where the laser strikes, is composed of metal powder. The black smoke generated by the laser melting is buffered for approximately ten millimeters. This buffering, with a second distance greater than the first, ensures that the air blower is at a suitable distance from the powder-coated surface, quickly blowing away the buffered black smoke without blowing away unformed powder. A small portion of the black smoke that cannot be completely blown away will escape to the lens. The speed-increasing orifice is at a suitable distance from the lens, adapted to the blowing position, and the first head body blows away the black smoke from the lens.
[0028] Optionally, the intake head includes an exhaust rectangular frame and a partition plate. The partition plate is inclinedly disposed within the exhaust rectangular frame and divides the exhaust rectangular frame into an upper chamber and a lower chamber. Both the upper chamber and the lower chamber are connected to the exhaust chamber. The lowest side of the partition plate is farther away from the exhaust chamber than the highest side. There are gaps between the top and bottom surfaces of the partition plate and the inner wall of the exhaust rectangular frame.
[0029] By adopting the above technical solution, without a partition plate, when black smoke is drawn out through the exhaust rectangle, a large amount of black smoke will accumulate around the perimeter of the rectangle. Furthermore, if the incoming black smoke travels at a high speed, it may even be blown directly onto the exhaust rectangle. With the partition plate, the black smoke can be drawn out from both the upper and lower chambers. Most of the black smoke is drawn out directly from the upper chamber, while a smaller portion is drawn out from the lower chamber. This also creates a difference in suction velocity between the upper and lower chambers, which helps to comprehensively remove the incoming black smoke.
[0030] Secondly, this application provides a 3D printer, which adopts the following technical solution:
[0031] A 3D printer includes the aforementioned independent flow field device for avoiding contamination of the lens and powder-coated surface.
[0032] In summary, this application includes at least one of the following beneficial technical effects:
[0033] 1. When laser melting is performed in the molding chamber, gas is introduced into the air blowing pipe. After passing through the air suction chamber, the gas is blown out from the air suction head. Since the air blowing head is set towards the powder-coated surface and the lens, the black smoke generated on the powder-coated surface and the black smoke that escaped to the lens are blown to the side where the air suction head is located. The air suction pipe can be connected to an external fan to draw in air, thereby drawing out the black smoke from the air suction head, air suction chamber and air suction pipe in sequence, reducing the pollution of the powder-coated surface and the lens caused by the black smoke.
[0034] 2. The gas in the blowing pipe enters the equalizing chamber and the air inlet rectangular frame in sequence, and then is blown out through the speed-increasing hole; the equalizing chamber is set to gradually expand from the blowing pipe toward the blowing head, which allows the gas in the blowing pipe to gradually diffuse in the equalizing chamber and increase the gas blowing area; the speed-increasing hole can accelerate the blown gas, making it easier to blow away the black smoke.
[0035] 3. The suction head includes an exhaust rectangle and a partition plate. The partition plate is inclined and set inside the exhaust rectangle, dividing the exhaust rectangle into an upper chamber and a lower chamber. Black smoke can be sucked away from the upper chamber and the lower chamber. Most of the black smoke is directly sucked away from the upper chamber, and a small part of the black smoke is sucked away from the lower chamber. At the same time, a suction and exhaust air velocity difference is created between the upper chamber and the lower chamber, which helps to completely suck away the blown black smoke. Attached Figure Description
[0036] Figure 1 This is a schematic diagram of the overall structure of an independent flow field device for avoiding contamination of the lens and powder surface according to an embodiment of this application.
[0037] Figure 2 This is another perspective of the overall structure of the independent flow field device used to avoid contamination of the lens and powder surface.
[0038] Figure 3 It is a structural diagram used to show the first and second head bodies.
[0039] Figure 4 This is a schematic diagram illustrating the structure of an equalizing orifice plate.
[0040] Figure 5 This is a structural diagram used to show the side of the partition.
[0041] Explanation of reference numerals in the attached drawings: 1. Air blowing section; 11. Air blowing pipe; 111. First branch pipe; 112. Second branch pipe; 113. Oxygen concentration sensor; 114. Wind speed sensor; 12. Pressure equalization chamber; 121. Pressure equalization orifice plate; 122. Mounting protrusion; 123. Mounting groove; 13. Air blowing head; 131. Inlet rectangular frame; 132. Speed increasing plate; 133. Speed increasing hole; 2. Air intake section; 21. Inlet pipe; 22. Inlet chamber; 23. Inlet head; 3. First chamber; 4. Second chamber; 5. First head body; 6. Second head body; 7. Outlet rectangular frame; 71. Upper chamber; 72. Lower chamber; 8. Divider plate. Detailed Implementation
[0042] The following is in conjunction with the appendix Figure 1-5 This application will be described in further detail.
[0043] This application discloses an independent flow field device and a 3D printer for avoiding contamination of the lens and powder surface.
[0044] In a first aspect, embodiments of this application disclose an independent flow field device for avoiding contamination of the lens and powder surface:
[0045] Reference Figure 1-2 An independent flow field device for preventing contamination of the lens and powder-coated surface includes an air blowing section 1 and an air intake section 2, which are positioned opposite each other on opposite sides of a forming chamber. The air blowing section 1 includes an air blowing pipe 11, a pressure equalization chamber 12, and an air blowing head 13. An oxygen concentration sensor 113 and a wind speed sensor 114 are fixedly mounted on the air blowing pipe 11. One end of the pressure equalization chamber 12 is connected to the air blowing pipe 11, and the other end is connected to the air blowing head 13. Both the pressure equalization chamber 12 and the air blowing head 13 are fixedly mounted on the side wall of the forming chamber, with the pressure equalization chamber 12 located on the outside of the forming chamber and the air blowing head 13 located on the inside of the forming chamber. The connection point between the pressure equalization chamber 12 and the air blowing head 13 penetrates the side wall of the forming chamber. The air blowing head 13 is positioned towards the powder-coated surface and the lens.
[0046] The suction section 2 includes a suction pipe 21, a suction chamber 22, and a suction head 23. One end of the suction chamber 22 is connected to the suction pipe 21, and the other end of the suction chamber 22 is connected to the suction head 23. The suction chamber 22 and the suction head 23 are both fixedly installed on the side wall of the molding chamber, with the suction chamber 22 located outside the molding chamber and the suction head 23 located inside the molding chamber. The connection between the suction chamber 22 and the suction head 23 penetrates the side wall of the molding chamber.
[0047] During laser melting in the molding chamber, gas is introduced into the air blowing pipe 11. After passing through the air suction chamber 22, the gas is blown out from the air suction head 23. Since the air blowing head 13 is set towards the powder-coated surface and the lens, the black smoke generated on the powder-coated surface and the black smoke that escaped to the lens are blown to the side where the air suction head 23 is located. The air suction pipe 21 can draw in air through an external fan, thereby drawing out the black smoke from the air suction head 23, the air suction chamber 22 and the air suction pipe 21 in sequence, reducing the pollution of the powder-coated surface and the lens caused by the black smoke.
[0048] Reference Figure 1-3 The equalizing chamber 12 includes a first chamber 3 and a second chamber 4, and the blowing head 13 includes a first head body 5 and a second head body 6. The first chamber 3 and the first head body 5 are connected to each other, as are the second chamber 4 and the second head body 6. The first head body 5 is positioned towards the lens, and the second head body 6 is positioned towards the powder-coated surface. The blowing pipe 11 is connected to the first chamber 3 and the second chamber 4 via a first branch pipe 111 and a second branch pipe 112, respectively. Blowing air onto the powder-coated surface and the lens separately helps to improve the accuracy and efficiency of blowing away black smoke.
[0049] Reference Figure 3-4The equalizing chamber 12 is gradually widened from the blowing pipe 11 toward the blowing head 13. The blowing head 13 includes an air inlet rectangular frame 131 and a speed-increasing plate 132 fixedly connected to the air inlet rectangular frame 131. The speed-increasing plate 132 has multiple speed-increasing holes 133. One end of the air inlet rectangular frame 131 is connected to the equalizing chamber 12, and the other end is connected to the speed-increasing holes 133. The gas in the blowing pipe 11 enters the equalizing chamber 12 and the air inlet rectangular frame 131 in sequence, and then is blown out through the speed-increasing holes 133. The equalizing chamber 12 is gradually widened from the blowing pipe 11 toward the blowing head 13, which allows the gas in the blowing pipe 11 to gradually diffuse in the equalizing chamber 12, increasing the gas blowing area; the speed-increasing holes 133 accelerate the blown gas, making it easier to blow away the black smoke.
[0050] Reference Figure 1 and Figure 3-4 Multiple pressure equalization plates 121 are spaced apart along the gradually expanding direction of the pressure equalization chamber 12. The multiple pressure equalization plates 121 can diffuse the gas flowing through the pressure equalization chamber 12 step by step, improve the diffusion effect, and thus improve the pressure equalization effect. This allows the gas in the pressure equalization chamber 12 to enter the air intake rectangular frame 131 over a large area, preventing the gas in the pressure equalization chamber 12 from concentrating and entering the air intake rectangular frame 131 from the middle, thereby avoiding the situation where the gas is blown out in a concentrated manner, resulting in only a local black smoke being blown away.
[0051] Reference Figure 3-4 Multiple mounting protrusions 122 are fixedly connected to both sides of the equalizing orifice plate 121 in the width direction. Mounting grooves 123 are provided on the top and bottom walls of the equalizing chamber 12 for the mounting protrusions 122 to be inserted into, facilitating the installation of the equalizing orifice plate 121. The thickness of the equalizing chamber 12 gradually decreases from the blowing pipe 11 towards the blowing head 13, which helps to pressurize and accelerate the gas in the equalizing chamber 12. The speed-increasing orifices 133 are triangularly arranged. For the same area and number of speed-increasing orifices 133, if circular, the wind speed would be too high to effectively blow away the black smoke; if square, although it has a better effect than circular, the processing cost of square holes is high. The speed-increasing orifices 133 in this application are triangularly arranged, which facilitates reasonable control of the blowing wind speed and saves processing costs.
[0052] Referring to the figure, the length of the first head body 5 is less than the length of the second head body 6, and the size of the speed-increasing hole 133 on the first head body 5 is greater than the size of the speed-increasing hole 133 on the second head body 6; the distance between the lowest point of the speed-increasing hole 133 on the first head body 5 and the bottom surface of the speed-increasing plate 132 on the first head body 5 is the first distance, and the distance between the lowest point of the speed-increasing hole 133 on the second head body 6 and the bottom surface of the speed-increasing plate 132 on the second head body 6 is the second distance, and the second distance is greater than the first distance.
[0053] The length of the first head body 5 is shorter than that of the second head body 6 because the air blown out by the second head body 5 needs to cover the entire printed curved surface of the powder-coated area, so it is longer. The first head body 6 is mainly for cleaning, so it does not need to be longer.
[0054] The size of the speed-increasing hole 133 on the first head body 5 is larger than that on the second head body 6. This is because the air blown out by the second head body 5 acts on the lens, while the air blown out by the second head body 6 acts on the powder-coated surface. The powder-coated surface is where black smoke is emitted, and there is a lot of black smoke. Therefore, the size of the speed-increasing hole 133 at this location is smaller than that at the lens. In other words, the wind speed acting on the powder-coated surface is greater than the wind speed at the lens.
[0055] Additionally, the printed curved surface, i.e. the powder-coated surface where the laser strikes, is made of metal powder. The black smoke generated by the laser melting will be buffered for about ten millimeters. This buffering, with the second distance being greater than the first, ensures that the distance between the air blower and the powder-coated surface is appropriate, quickly blowing away the black smoke buffered on the powder-coated surface without blowing away the unformed powder. A small portion of the black smoke that cannot be blown away will escape to the lens. The speed-increasing orifice 133 is at an appropriate distance from the lens, adapted to the position of the air blower, so the first head body 5 blows away the black smoke from the lens.
[0056] Reference Figure 1 and Figure 5 The intake head 23 includes an exhaust rectangular frame 7 and a partition plate 8. The partition plate 8 is inclinedly disposed within the exhaust rectangular frame 7 and divides the exhaust rectangular frame 7 into an upper chamber 71 and a lower chamber 72. Both the upper chamber 71 and the lower chamber 72 are connected to the exhaust chamber. The lowest side of the partition plate 8 is farther away from the exhaust chamber than the highest side. There are gaps between the top and bottom surfaces of the partition plate 8 and the inner wall of the exhaust rectangular frame 7.
[0057] Without the partition plate 8, when black smoke is drawn out through the exhaust rectangle 7, a large amount of black smoke will accumulate around the perimeter of the exhaust rectangle 7. Furthermore, if the incoming black smoke travels at a high speed, it may even be blown directly onto the exhaust rectangle 7. With the partition plate 8, black smoke can be drawn out from both the upper chamber 71 and the lower chamber 72. Most of the black smoke is drawn out directly from the upper chamber 71, while a smaller portion is drawn out from the lower chamber 72. This also creates a difference in suction velocity between the upper and lower chambers 71 and 72, which helps to completely remove the incoming black smoke.
[0058] The implementation principle of an independent flow field device for avoiding contamination of the lens and powder coating surface according to an embodiment of this application is as follows: gas is introduced into the blowing pipe 11, and the gas is blown out from the suction head 23 after passing through the suction chamber 22. Since the blowing head 13 is set towards the powder coating surface and the lens, the black smoke generated on the powder coating surface and the black smoke that escaped to the lens are blown to the side where the suction head 23 is located. The suction pipe 21 can be connected to an external fan to draw in air, thereby drawing out the black smoke from the suction head 23, the suction chamber 22 and the suction pipe 21 in sequence, reducing the contamination of the powder coating surface and the lens caused by the black smoke.
[0059] Secondly, this application discloses a 3D printer:
[0060] A 3D printer includes the aforementioned independent flow field device for avoiding contamination of the lens and powder-coated surface.
[0061] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.
Claims
1. An independent flow field device for avoiding contamination of lens and powder-coated surfaces, characterized in that: It includes an air blowing section (1) and an air suction section (2), which are disposed opposite to each other on both sides of the molding chamber; The air blowing section (1) includes an air blowing pipe (11), a pressure equalization chamber (12), and an air blowing head (13). One end of the pressure equalization chamber (12) is connected to the air blowing pipe (11), and the other end of the pressure equalization chamber (12) is connected to the air blowing head (13). The pressure equalization chamber (12) and the air blowing head (13) are both fixedly installed on the side wall of the molding chamber. The pressure equalization chamber (12) is located on the outside of the molding chamber, and the air blowing head (13) is located on the inside of the molding chamber. The connection between the pressure equalization chamber (12) and the air blowing head (13) penetrates the side wall of the molding chamber. The air blowing head (13) is positioned facing the powder-coated surface and the lens. The suction section (2) includes a suction pipe (21), a suction chamber (22), and a suction head (23). One end of the suction chamber (22) is connected to the suction pipe (21), and the other end of the suction chamber (22) is connected to the suction head (23). The suction chamber (22) and the suction head (23) are both fixedly installed on the side wall of the molding chamber. The suction chamber (22) is located outside the molding chamber, and the suction head (23) is located inside the molding chamber. The connection between the suction chamber (22) and the suction head (23) penetrates the side wall of the molding chamber.
2. The independent flow field device for avoiding contamination of lens and powder surface according to claim 1, characterized in that: The equalizing chamber (12) includes a first chamber (3) and a second chamber (4), and the blowing head (13) includes a first head body (5) and a second head body (6). The first chamber (3) and the first head body (5) are connected to each other, and the second chamber (4) and the second head body (6) are connected to each other. The first head body (5) is positioned towards the lens, and the second head body (6) is positioned towards the powder-coated surface. The air blowing pipe (11) is connected to the first cabin (3) and the second cabin (4) through the first branch pipe (111) and the second branch pipe (112) respectively.
3. The independent flow field device for avoiding contamination of lens and powder surface according to claim 2, characterized in that: The equalizing chamber (12) is gradually widened from the air blowing pipe (11) toward the air blowing head (13). The air blowing head (13) includes an air inlet rectangular frame (131) and a speed-increasing plate (132) fixedly connected to the air inlet rectangular frame (131). The speed-increasing plate (132) has a plurality of speed-increasing holes (133). The opening at one end of the air inlet rectangular frame (131) is connected to the equalizing chamber (12), and the opening at the other end of the air inlet rectangular frame (131) is connected to the speed-increasing holes (133).
4. The independent flow field device for avoiding contamination of lens and powder surface according to claim 3, characterized in that: Multiple pressure equalization orifice plates (121) are arranged at intervals along the gradually expanding direction of the pressure equalization chamber (12).
5. The independent flow field device for avoiding contamination of lens and powder surface according to claim 4, characterized in that: Multiple mounting protrusions (122) are fixedly connected to both sides of the equalizing plate (121) in the width direction. Mounting grooves (123) are provided on the top and bottom walls of the equalizing chamber (12) for the mounting protrusions (122) to be inserted into.
6. The independent flow field device for avoiding contamination of lens and powder surface according to claim 3, characterized in that: The thickness of the equalizing chamber (12) gradually decreases from the air blowing pipe (11) toward the air blowing head (13).
7. The independent flow field device for avoiding contamination of lens and powder surface according to claim 3, characterized in that: The speed-increasing orifice (133) is arranged in a triangular shape.
8. The independent flow field device for avoiding contamination of lens and powder surface according to claim 3, characterized in that: The length of the first head body (5) is less than the length of the second head body (6), and the size of the speed-increasing hole (133) on the first head body (5) is greater than the size of the speed-increasing hole (133) on the second head body (6); the distance between the lowest point of the speed-increasing hole (133) on the first head body (5) and the bottom surface of the speed-increasing plate (132) on the first head body (5) is the first distance, and the distance between the lowest point of the speed-increasing hole (133) on the second head body (6) and the bottom surface of the speed-increasing plate (132) on the second head body (6) is the second distance, and the second distance is greater than the first distance.
9. The independent flow field device for avoiding contamination of lens and powder surface according to claim 1, characterized in that: The intake head (23) includes an exhaust rectangular frame (7) and a partition plate (8). The partition plate (8) is inclinedly disposed within the exhaust rectangular frame (7) and divides the exhaust rectangular frame (7) into an upper chamber (71) and a lower chamber (72). Both the upper chamber (71) and the lower chamber (72) are connected to the exhaust chamber. The lowest side of the partition plate (8) is farther away from the exhaust chamber than the highest side. There are gaps between the top and bottom surfaces of the partition plate (8) and the inner wall of the exhaust rectangular frame (7).
10. A 3D printer, characterized in that: Includes the independent flow field device for avoiding contamination of the lens and powder surface as described in any one of claims 1-9.