An air inlet adapter for metal 3D printing equipment

Abstract

The present invention relates to an air inlet adapter for metal 3D printing equipment, comprising a shell with an air inlet and an air outlet, and characterized in that: a chamber connecting the air inlet and the air outlet is provided inside the shell, a first baffle, a second baffle and a third baffle are connected to the cavity wall of the cavity, and the first baffle, the second baffle and the third baffle are distributed in sequence from the air inlet to the air outlet. In addition, a first gap is provided between at least one side of the periphery of the first baffle and the cavity wall of the cavity, a gap is provided in the middle of the second baffle, and a second gap is provided between at least one side of the periphery of the third baffle and the cavity wall of the cavity, so that external airflow enters the cavity from the air inlet, and passes through the first gap, the gap and the second gap in sequence, and then flows out through the air outlet, so that the air inlet adapter has a simple structure and a better airflow buffering effect.

Description

Technical Field

[0001] The invention relates to the technical field of accessories for metal 3D printing equipment, and in particular to an air inlet adapter for metal 3D printing equipment. Background Art

[0002] Additive Manufacturing (AM), commonly known as 3D printing, is a cumulative manufacturing technology for rapid prototyping of three-dimensional objects. As an important branch of additive manufacturing, metal additive manufacturing is a new manufacturing technology that uses metal powder / wire as raw materials, high-energy beams (laser / electron beam / arc / plasma beam, etc.) as tools, and computer three-dimensional CAD data models as the basis. It uses the principle of discrete-accumulation, melts the laid powder to be formed layer by layer under the control of software and CNC systems, and then solidifies and accumulates layer by layer to manufacture high-performance metal components. The machine that prints products using 3D printing technology is called 3D printing equipment.

[0003] A general 3D printer includes a molding chamber. During 3D printing, in order to prevent the oxygen content in the molding chamber from being too high and the powder to be molded from reacting with oxygen, an inert gas is generally filled into the molding chamber through the air duct system to form a layer of protective gas laminar flow on the molding surface of the metal powder. Since the airflow direction output by the air duct system is chaotic and the flow rate is fast, if the air blown out by the air duct system is directly delivered to the molding chamber, it will affect the molding effect of the metal powder; and the air outlet of the air duct system and the air inlet of the molding chamber are inconsistent in shape. Usually, the air outlet of the air duct system is a circular pipe, and the air inlet of the molding chamber is a rectangular air inlet, so that the air outlet of the air duct system cannot be directly connected to the air inlet of the molding chamber. Therefore, it is usually necessary to connect an air inlet adapter between the air duct system and the molding chamber to convert the circular air duct into a rectangular air duct and achieve the purpose of uniform wind direction and uniform wind speed.

[0004] The Chinese utility model patent with patent number CN201820701667.8 (authorization announcement number CN208263445U) discloses a 3D printing device, including a molding chamber and a molding container arranged in the molding chamber, wherein a first air intake structure is provided on the first side of the molding chamber, and the air intake of the first air intake structure faces the molding container. In the direction from the connecting port of the first air intake structure to the air intake, the width of the first air intake structure gradually increases and its height gradually decreases. The first air intake structure includes an expansion portion and a straight-through portion connected to each other, wherein, in the direction from the connecting port of the first air intake structure to the air intake, the width of the expansion portion gradually increases and its height gradually decreases. A first air intake guide element is provided inside the first air intake structure to form a plurality of air intake ducts. In the direction from the connecting port of the first air intake structure to the air intake, the first air intake guide element gradually expands outward. A first grid plate is provided at the air intake of the first air intake structure, and the first grid plate is provided with a first air intake grid. The thickness dimension of the first grid plate is greater than the opening width dimension of the first air intake grid.

[0005] The first air intake structure (referred to as an air intake adapter in this application) of the above-mentioned 3D printing device buffers the airflow by splitting the airflow twice. However, the air intake structure of the 3D printing device has the following deficiencies: ① The channels in the air intake structure are mainly straight channels, and some are arc-shaped channels, which makes the flow path of the gas inside the air intake structure shorter, the airflow buffering is insufficient, and the gas flow rate is still fast; ② Because the airflow first undergoes the first diversion in the width of the air intake structure, and then undergoes the second diversion in the width and height directions, the airflow in different channels in the width direction will always maintain differences in concentration, speed, etc., resulting in poor overall uniformity of the airflow flowing out of the grid plate, thereby making the airflow uniformity out of the air outlet poor; ③ Because the channels formed by the guide elements are all distributed side by side along the width direction of the air intake structure, and the guide elements gradually expand outward along the fluid conveying direction, the length of the channel located in the middle of the air intake structure is shorter than the length of the channel located on both sides of the air intake structure, and different channels have different buffering effects on the gas, so that the gas flow rates output through different channels are still quite different, that is, the uniformity of the gas flow rate after diversion is still poor; ④ Multiple guide elements and grids need to be arranged inside the air intake structure, and the structure is complex, resulting in cumbersome processing procedures and low production efficiency of the air intake structure. Summary of the invention

[0006] The first technical problem to be solved by the present invention is to provide an air inlet adapter for a metal 3D printing device with a simple structure and better airflow buffering effect in response to the above-mentioned technical status quo.

[0007] The second technical problem to be solved by the present invention is to provide an air inlet adapter for a metal 3D printing device with better overall uniformity of airflow in response to the above-mentioned technical status quo.

[0008] The second technical problem to be solved by the present invention is to provide an air inlet adapter for a metal 3D printing device with better gas flow rate uniformity in response to the above-mentioned technical status.

[0009] The technical solution adopted by the present invention to solve the above-mentioned first technical problem is: an air inlet adapter for metal 3D printing equipment, comprising a shell having an air inlet and an air outlet, characterized in that: a chamber connecting the air inlet and the air outlet is provided inside the shell, and a first baffle, a second baffle and a third baffle are connected to the cavity wall of the cavity, and the first baffle, the second baffle and the third baffle are distributed in sequence from the air inlet to the air outlet. In addition, a first gap is provided between at least one side of the periphery of the first baffle and the cavity wall of the cavity, a gap is provided in the middle of the second baffle, and a second gap is provided between at least one side of the periphery of the third baffle and the cavity wall of the cavity, so that the external airflow enters the cavity from the air inlet, and passes through the first gap, the gap and the second gap in sequence before flowing out through the air outlet.

[0010] In order to make the air flow flow to the air outlet more smoothly, and at the same time, in order to arrange the air inlet adapter reasonably to avoid interference between the air inlet adapter and other components such as the fan, the chamber is in the shape of a horizontally placed cylinder, and the air inlet is arranged at the rear side of the side of the cylinder, and the air outlet is arranged at the front side of the side of the cylinder. According to the wall attachment effect, the air flow will flow along the wall of the chamber after entering the chamber, and the side of the cylinder is an arc surface. The arc surface design can reduce wind resistance, so that the air flow can flow to the air outlet more smoothly and avoid air flow accumulation in the chamber; the design of the chamber shape can make the processing of the air inlet adapter simpler; because a fan is usually installed above the air inlet adapter, placing the cylinder horizontally can avoid interference between the air inlet adapter and the fan.

[0011] Since powder is usually spread on a rectangular substrate in the molding chamber, the gas entering the molding chamber is preferably evenly distributed in the left-right direction, so as to avoid large fluctuations in the airflow above the substrate and affect the metal powder molding. In order to make the airflow more dispersed in the left-right direction and thus more evenly distributed, the air outlet is rectangular, the length direction of the rectangle is the left-right direction, and the second gap is set along the left-right direction.

[0012] The technical solution adopted by the present invention to solve the above-mentioned second technical problem is as follows: the third baffle is arranged vertically, and the upper and lower peripheral sides of the third baffle have the second gap with the cavity wall of the chamber; an air outlet channel is also arranged inside the shell, the inlet of the air outlet channel is connected to the chamber, the outlet of the air outlet channel is the air outlet, and at least one partition plate is arranged inside the air outlet channel, and the partition plate divides the air outlet channel into at least two sub-channels distributed side by side in the left and right directions. After the airflow is layered up and down by the third baffle, the airflow is layered left and right by the partition plate, so that the airflow undergoes diversion in two different directions successively, so that the upper and lower layers of airflow can be mixed in the sub-channel, so that the overall uniformity of the airflow is better.

[0013] To promote the airflow to flow out of the air outlet, the length of the air outlet is L1, the length of the cylinder is L2, and L1≤L2. According to Bernoulli's principle, when the length of the air outlet is less than the length of the cylinder, the airflow can be accelerated to pass through a narrower air outlet.

[0014] The technical solution adopted by the present invention to solve the above-mentioned second technical problem is: the first baffle, the second baffle and the third baffle are arranged side by side, and the first baffle has the first gap on both sides of the periphery of the first baffle and the cavity wall of the chamber, and the third baffle has the second gap on both sides of the periphery of the third baffle and the cavity wall of the chamber. The airflow entering the chamber is first split through the two first gaps, then the airflow is first merged through the gap, and then the airflow is secondly split through the two second gaps, and finally the airflow is merged for the second time through the air outlet, so that the airflow can be fully uniform after the two splits and merges, so that the overall uniformity of the airflow is better.

[0015] The technical solution adopted by the present invention to solve the third technical problem is as follows: the air inlet and the air outlet are coaxially arranged, and the common plane of the air inlet axis and the cylinder axis is the first plane, and the chamber, the first baffle, the second baffle and the third baffle are all arranged in mirror symmetry with respect to the first plane. This design enables the first gaps on the upper and lower sides of the first baffle to be arranged in mirror symmetry with respect to the first plane, the gaps to be arranged in mirror symmetry with respect to the first plane, and the second gaps on the upper and lower sides of the third baffle to be arranged in mirror symmetry with respect to the first plane, so that the airflow entering the chamber flows along the paths of both sides of the chamber in a completely consistent manner, thereby making the buffering effect of the chamber on the airflow on both sides basically the same, avoiding large differences in the flow rates of the airflow on both sides, and making the gas flow rate more uniform.

[0016] In order to make the first baffle and the third baffle have basically the same airflow diversion effect, the first baffle, the second baffle and the third baffle are all flat plates arranged vertically, the bottom surface diameter of the cylinder is D, and the first baffle, the second baffle and the third baffle are respectively located at 0.25D, 0.5D and 0.75D of the bottom surface of the cylinder from back to front.

[0017] In order to make the first baffle and the third baffle have substantially the same airflow diversion effect, the height of the first gap is H1, the height of the second gap is H2, the height of the slit is H3, and H1 = H2 < H3 < 0.5D.

[0018] In order to balance the speed of airflow passing through the gap, H3 is 1.5 to 3 times of H2. If the difference between H3 and H2 is large, the gas flow rate will be too slow, and it will be difficult for the airflow to pass through the gap. If the difference between H3 and H2 is small at the gap, the gas flow rate at the gap will be too fast, which will easily cause airflow turbulence.

[0019] In order to further reduce the gas flow rate, the flow area of ​​the gas inlet is S1, the flow area of ​​the gas outlet is S2, and S1≤S2.

[0020] Compared with the prior art, the advantages of the present invention are: an air flow channel is formed between three baffles spaced apart from the air inlet to the air outlet and the cavity wall of the chamber, so that the structure of the air inlet adapter is simpler, the processing procedure can be simplified, and thus the production efficiency is improved; moreover, the positions of the first gap, the slit and the second gap are set so that the airflow first enters the chamber through the air inlet, and then flows to the periphery of the first baffle, the middle of the second baffle, and the periphery of the third baffle in sequence, and finally flows out through the air outlet, so that the flow path of the airflow in the chamber is in a zigzag shape. Compared with a straight or curved flow path, the zigzag flow path is longer, so that the airflow can be fully buffered in the chamber, the airflow deceleration effect is better, and the airflow speed entering the molding chamber can be made more moderate, thereby avoiding affecting the molding effect of the metal powder. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the structure of the embodiment of the present invention after installation (in a top view);

[0022] Figure 2 is a three-dimensional structural diagram of an embodiment of the present invention;

[0023] Figure 3 It is a side view of an embodiment of the present invention. DETAILED DESCRIPTION

[0024] The present invention is further described in detail below with reference to the accompanying drawings.

[0025] like Figures 1 to 3Shown is the best embodiment of the present invention.

[0026] The air inlet adapter of the metal 3D printing device in this embodiment is as follows: Figures 2-3 As shown, it includes a shell 1 having an air inlet 111 and an air outlet 121. A chamber 11 connecting the air inlet 111 and the air outlet 121 is provided inside the shell 1, and a first baffle 2, a second baffle 3 and a third baffle 4 are connected to the cavity wall of the chamber 11, and the first baffle 2, the second baffle 3 and the third baffle 4 are sequentially spaced from the air inlet 111 to the air outlet 121. In addition, a first gap 100 is provided between at least one side of the periphery of the first baffle 2 and the cavity wall of the chamber 11, a gap 31 is provided in the middle of the second baffle 3, and a second gap 200 is provided between at least one side of the periphery of the third baffle 4 and the cavity wall of the chamber 11, so that the external airflow enters the chamber 11 from the air inlet 111, and sequentially passes through the first gap 100, the gap 31, and the second gap 200 before flowing out through the air outlet 121.

[0027] The air inlet adapter of the metal 3D printing equipment in this embodiment has a simpler structure and can simplify the processing steps, thereby improving production efficiency. Moreover, the flow path of the airflow in the chamber 11 is in a zigzag shape. Compared with a straight or curved flow path, the zigzag flow path is longer, so that the airflow in the chamber 11 can be fully buffered, and the airflow deceleration effect is better, which can make the airflow speed entering the molding chamber 7 more moderate, thereby avoiding affecting the molding effect of the metal powder.

[0028] The chamber 11 is in the shape of a horizontal cylinder (see Figure 1 and Figure 3 ), and the air inlet 111 is arranged at the rear side of the side of the cylinder, and the air outlet 121 is arranged at the front side of the side of the cylinder (see Figure 1 ). According to the wall attachment effect, after the airflow enters the chamber 11, it will flow along the wall of the chamber 11. The side of the cylinder is an arc surface. The arc surface design can reduce wind resistance, so that the airflow can flow more smoothly to the air outlet, avoiding the accumulation of airflow in the chamber; the design of the shape of the chamber 11 can make the processing of the air inlet adapter simpler; because a fan is usually installed above the air inlet adapter, placing the cylinder horizontally can avoid interference between the air inlet adapter and the fan. The flow area of ​​the air inlet 111 is S1, and the flow area of ​​the air outlet 121 is S2, S1≤S2, so that the gas flow rate can be further reduced.

[0029] like Figure 3As shown, the first baffle 2, the second baffle 3 and the third baffle 4 are arranged side by side, and the two opposite sides on the periphery of the first baffle 2 have a first gap 100 with the cavity wall of the chamber 11, and the two opposite sides on the periphery of the third baffle 4 have a second gap 200 with the cavity wall of the chamber 11, so that the airflow can be fully uniformed after two diversions and confluences, so that the overall uniformity of the airflow is better. Specifically, in this embodiment, the first baffle 2 and the third baffle 4 are both arranged vertically, and the upper and lower sides of the periphery of the first baffle 2 have a first gap 100 with the cavity wall of the chamber 11, and the upper and lower sides of the periphery of the third baffle 4 have a second gap 200 with the cavity wall of the chamber 11.

[0030] The air inlet 111 and the air outlet 121 are coaxially arranged (see Figure 1 and Figure 3 ), let the common plane of the air inlet 111 axis and the cylinder axis be the first plane 300, the chamber 11, the first baffle 2, the second baffle 3 and the third baffle 4 are all arranged in mirror symmetry with respect to the first plane 300 (see Figure 3 ), so that the airflow entering the chamber 11 flows along the paths of both sides of the chamber 11 in a completely consistent manner, so that the buffering effect of the chamber 11 on the airflow on both sides is basically the same, avoiding a large difference in the flow rate of the airflow on both sides, and making the gas flow rate more uniform. The first baffle 2, the second baffle 3 and the third baffle 4 are all flat plates, the bottom diameter of the cylinder is D, and the first baffle 2, the second baffle 3 and the third baffle 4 are respectively located at 0.25D, 0.5D and 0.75D of the bottom surface of the cylinder from back to front (see Figure 3 ). The height of the first gap 100 is H1, the height of the second gap 200 is H2, the height of the gap 31 is H3, and H1=H2<H3<0.5D (see Figure 2 ). H3 is 1.5 to 3 times of H2; in this embodiment, H3 is 2 times of H2.

[0031] The air outlet 121 is rectangular, and the length direction of the rectangle is the left-right direction (see Figure 1 ), so as to match the rectangular substrate 6. The second gap 200 is arranged along the left and right directions (see Figure 2 and Figure 3 ), so that the airflow can be more dispersed in the left and right directions and the airflow distribution can be more uniform. The length of the air outlet 121 is L1, the length of the cylinder is L2, and L1≤L2 (see Figure 1 ); According to Bernoulli's principle, such a design can accelerate the airflow through the narrower air outlet 121.

[0032] like Figure 1As shown, an air outlet channel 12 is also provided inside the shell 1, the inlet of the air outlet channel 12 is connected to the chamber 11, the outlet of the air outlet channel 12 is an air outlet 121, and at least one partition plate 5 is provided in the air outlet channel 12, the partition plate 5 divides the air outlet channel 12 into at least two sub-channels 122 distributed side by side in the left and right directions, so that the third baffle 4 first separates the airflow into upper and lower layers, and then separates the airflow into left and right layers through the partition plate 5, so that the airflow undergoes diversion in two different directions in succession, so that the upper and lower layers of airflow can be mixed in the sub-channel 122, so that the overall uniformity of the airflow is better.

Claims

1. An air inlet adapter for a metal 3D printing device, comprising a housing (1) having an air inlet (111) and an air outlet (121), characterized in that: The shell (1) is provided with a chamber (11) communicating with the air inlet (111) and the air outlet (121), the chamber wall of the chamber (11) being connected with a first baffle (2), a second baffle (3) and a third baffle (4), and the first baffle (2), the second baffle (3) and the third baffle (4) are sequentially spaced from the air inlet (111) to the air outlet (121), and furthermore, a first gap (100) is provided between at least one side of the periphery of the first baffle (2) and the chamber wall of the chamber (11), and the middle portion of the second baffle (3) is opened. A gap (31) is provided, and a second gap (200) is provided between at least one side of the periphery of the third baffle (4) and the cavity wall of the chamber (11), so that external airflow enters the chamber (11) from the air inlet (111), passes through the first gap (100), the gap (31), and the second gap (200) in sequence, and then flows out through the air outlet (121); the chamber (11) is in the shape of a horizontally placed cylinder; the air inlet (111) is arranged on the rear side of the side of the cylinder, and the air outlet (121) is arranged on the front side of the side of the cylinder.

2. The air inlet adapter of the metal 3D printing device according to claim 1, characterized in that: The air outlet (121) is rectangular, the length direction of the rectangle is the left-right direction, and the second gap (200) is arranged along the left-right direction.

3. The air inlet adapter of the metal 3D printing device according to claim 2, characterized in that: The third baffle (4) is arranged in the vertical direction, and the upper side and the lower side of the peripheral edge of the third baffle (4) have the second gap (200) with the cavity wall of the chamber (11); the shell (1) is also provided with an air outlet channel (12), the inlet of the air outlet channel (12) is connected to the chamber (11), the outlet of the air outlet channel (12) is the air outlet (121), and at least one partition plate (5) is provided in the air outlet channel (12), and the partition plate (5) divides the air outlet channel (12) into at least two sub-channels (122) distributed side by side in the left-right direction.

4. The air inlet adapter of the metal 3D printing device according to claim 2, characterized in that: The length of the air outlet (121) is L1, the length of the cylinder is L2, and L1≤L2.

5. The air inlet adapter of the metal 3D printing device according to claim 1, characterized in that: The first baffle plate (2), the second baffle plate (3) and the third baffle plate (4) are arranged side by side, and the first baffle plate (2) has the first gap (100) on two opposite sides of the periphery with the cavity wall of the chamber (11), and the third baffle plate (4) has the second gap (200) on two opposite sides of the periphery with the cavity wall of the chamber (11).

6. The air inlet adapter of the metal 3D printing device according to claim 5, characterized in that: The air inlet (111) and the air outlet (121) are coaxially arranged, so that the common plane of the axis of the air inlet (111) and the axis of the cylinder is a first plane (300), and the chamber (11), the first baffle (2), the second baffle (3) and the third baffle (4) are all arranged in mirror symmetry with respect to the first plane (300).

7. The air inlet adapter of the metal 3D printing device according to claim 6, characterized in that: The first baffle (2), the second baffle (3) and the third baffle (4) are all flat plates arranged in the vertical direction. The bottom surface diameter of the cylinder is D. The first baffle (2), the second baffle (3) and the third baffle (4) are respectively located at 0.25D, 0.5D and 0.75D of the bottom surface of the cylinder from the back to the front.

8. The air inlet adapter of the metal 3D printing device according to claim 7, characterized in that: The height of the first gap (100) is H1, the height of the second gap (200) is H2, the height of the gap (31) is H3, and H1=H2<H3<0.5D.

9. The air inlet adapter of the metal 3D printing device according to claim 8, characterized in that: H3 is 1.5 to 3 times that of H2.

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