Metal powder bed additive manufacturing system based on three-layer wind field

Abstract

The metal powder bed additive manufacturing system based on the three-layer wind field comprises a forming cavity, a stratosphere air inlet channel, a flow restraining layer air inlet channel and an air purifying layer air inlet channel are sequentially arranged on an air inlet face from bottom to top, and the stratosphere air inlet channel and the air purifying layer air inlet channel extend in the first direction; an air inlet channel outlet of the flow suppression layer air inlet channel points to the second direction; the air outlet face is provided with a stratosphere air outlet channel, a flow restraining layer air outlet channel and an air purifying layer air outlet channel, the first direction is the direction from the air inlet face to the air outlet face and is parallel to the printing breadth, and the second direction inclines towards the printing breadth relative to the first direction. Through the three-layer wind field design, the stability and the wind speed of the parallel wind field beside the printing breadth and the laser lens are guaranteed, internal flocculation is avoided, printing by-products are blown and collected to the maximum extent, and the printing breadth and the laser lens are prevented from being polluted.

Description

Technical Field

[0001] The present application belongs to the technical field of metal powder bed additive manufacturing, and specifically relates to a metal powder bed additive manufacturing system based on a three-layer wind field. Background Art

[0002] In order to prevent smoke and other byproducts generated during printing from contaminating the printing surface or the laser lens, maintain the stability of the printing process, and ensure the continuity of the optical transmission path, the wind field design and printing system in the molding chamber of the metal powder bed additive manufacturing equipment become one of the key considerations.

[0003] There are two main wind field designs in the prior art. The first one is to set a blowing port and an air suction port on the opposite side walls inside the molding cavity. The blowing port is usually at a certain height from the printing plane to suck away the smoke and dust during the printing process. This setting method cannot collect all the smoke and dust into the air suction port, resulting in by-products that continue to interfere with normal printing and shorten the service life of the laser lens. The second is to form multiple wind walls through multiple wind fields with different heights. This method does not strictly distinguish between the functional designs of air inlets at different heights. The airflows between different blowing ports are easy to affect each other, destroying the stability of the wind field in the molding cavity, resulting in turbulence between the lower printing format and the top laser lens, causing smoke and dust to contaminate the printing format and the laser lens. Summary of the invention

[0004] The purpose of this application is to provide a metal powder bed additive manufacturing system based on a three-layer wind field, so as to solve the technical problem that the wind field setting in the molding chamber of the metal powder bed additive manufacturing system in the prior art cannot collect all the smoke and dust into the air suction port, resulting in by-products continuously interfering with normal printing and shortening the service life of the laser lens.

[0005] In order to achieve the above objectives, the present application provides a metal powder bed additive manufacturing system based on a three-layer wind field, comprising:

[0006] A molding cavity, wherein the bottom surface is provided with a printing surface, the top surface is provided with a lens mounting surface, and the side wall includes an air inlet surface and an air outlet surface which are arranged opposite to each other, wherein the air inlet surface is sequentially arranged with a stratospheric air inlet channel, a flow suppression layer air inlet channel and a clean air layer air inlet channel from bottom to top, wherein the stratospheric air inlet channel and the clean air layer air inlet channel are extended in a first direction, and an air inlet channel outlet of the flow suppression layer air inlet channel is arranged to point to a second direction;

[0007] A blowing device, used for blowing air into the cavity of the molding cavity through the stratospheric air inlet channel, the suppression layer air inlet channel and the clean air layer air inlet channel;

[0008] Among them, the wind outlet surface is arranged with a stratospheric air outlet channel, a stratospheric air outlet channel and a clean air layer air outlet channel, which are respectively used to discharge the wind blown in by the stratospheric air inlet channel, the stratospheric air inlet channel and the clean air layer air inlet channel; the first direction is the direction in which the air inlet surface points to the air outlet surface, and the first direction is parallel to the printing format; the second direction is inclined toward the printing format direction relative to the first direction.

[0009] In one or more embodiments, the molding cavity further includes a pair of first guide plates and a pair of second guide plates arranged on the air inlet surface and penetrating the side walls of the molding cavity, the gap between the pair of first guide plates forming the stratospheric air inlet channel, and the gap between the pair of second guide plates forming the clean air layer air inlet channel.

[0010] In one or more embodiments, the molding cavity further includes a flow limiting plate arranged at the inner end of the second guide plate, and the flow limiting plate extends from the inner end of the second guide plate toward another second guide plate to increase the fluid velocity at the outlet of the clean air layer inlet channel.

[0011] In one or more embodiments, the molding cavity further includes a plurality of air guide plates arranged between the inner ends of a pair of the first air guide plates, and the plurality of air guide plates are arranged at intervals to separate the outlet of the stratospheric air inlet channel into a plurality of relatively independent outlets.

[0012] In one or more embodiments, the stratospheric air outlet channel is arranged at the orthogonal projection of the stratospheric air inlet channel on the air outlet surface; the clean air layer air outlet channel is arranged at the orthogonal projection of the clean air layer air inlet channel on the air outlet surface; the air outlet channel inlet of the suppression layer air outlet channel is arranged at the orthogonal projection of the suppression layer air inlet channel on the air outlet surface.

[0013] In one or more embodiments, the molding cavity further includes an air inlet hood arranged on the air inlet surface, the air inlet hood being located between the clean air layer air inlet channel and the stratospheric air inlet channel, and having the suppression layer air inlet channel formed therein, the air inlet channel inlet of the suppression layer air inlet channel being located on the air inlet surface and penetrating through the side wall of the molding cavity, and the air inlet channel outlet being arranged on the air inlet hood.

[0014] In one or more embodiments, the air inlet hood includes a pair of side panels arranged opposite to each other, a top plate respectively located between the top, middle and lower parts of the pair of side panels, an air inlet plate and a bottom plate, the air inlet plate and the bottom plate are arranged obliquely relative to the printing format, and a plurality of the air inlet channel outlets are evenly arranged on at least a partial area of ​​the air inlet plate and the bottom plate.

[0015] In one or more embodiments, the air inlet channel inlet of the flow suppression layer air inlet channel includes a horizontal flow section and a guide section arranged in sequence, the bottom side of the guide section is inclined toward the printing format, and the top plate is inclined toward the printing format and parallel to the bottom side of the guide section.

[0016] In one or more embodiments, the molding cavity further includes an air outlet hood arranged on the air outlet surface, an air outlet channel of the flow suppression layer is formed between the air outlet hood and the air outlet surface, an air outlet channel inlet of the air outlet channel of the flow suppression layer is arranged at the bottom end of the air outlet hood, and an air outlet channel outlet is located on the air outlet surface and is arranged through the side wall of the molding cavity.

[0017] In one or more embodiments, the second direction forms an angle of 5° to 30° with the first direction.

[0018] Different from the prior art, the beneficial effects of this application are:

[0019] The present application ensures the stability and wind speed of the parallel wind field next to the printing format and the laser lens through a three-layer wind field design, avoids flocculation inside the molding cavity, blows and collects printing by-products as much as possible, prevents the printing format and the laser lens from being contaminated, improves the quality reliability of the prints, and enhances the market competitiveness of the products. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a cross-sectional structural schematic diagram of an embodiment of a metal powder bed additive manufacturing system of the present application;

[0022] Figure 2 It is a structural schematic diagram of an embodiment of a metal powder bed additive manufacturing system of the present application;

[0023] Figure 3 This is a structural schematic diagram from another perspective of an embodiment of the metal powder bed additive manufacturing system of the present application.

[0024] Reference numerals:

[0025] Molding cavity 10; printing format 101; lens mounting surface 102; air inlet surface 103; air outlet surface 104; stratospheric air inlet channel 105; damping layer air inlet channel 106; air inlet channel inlet 1061; stratospheric section 10611; guide section 10612; air inlet channel outlet 1062; clean air layer air inlet channel 107; stratospheric air outlet channel 108; damping layer air outlet channel 109; air outlet channel inlet 1091; air outlet channel outlet 1092; clean air layer air outlet channel 110; first guide plate 111; second guide plate 112; flow limiting plate 113; air guide plate 114; air inlet cover 115; side plate 1151; top plate 1152; air inlet plate 1153; bottom plate 1154; air outlet cover 116. DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work should fall within the scope of protection of the present application.

[0027] In order to solve the problems existing in the wind field design of current metal powder bed additive manufacturing equipment, the applicant has developed a new type of metal powder bed additive manufacturing system. The system uses a three-layer wind field design to blow away printing by-products as much as possible to prevent the printing format and laser lens from being contaminated. It can also ensure the stability of each parallel wind field, eliminate smoke and dust accumulation areas, and improve the quality reliability of printed parts.

[0028] Specifically, see Figures 1 to 3 , Figure 1 is a schematic cross-sectional view of an embodiment of a metal powder bed additive manufacturing system of the present application, Figure 2 is a structural schematic diagram of an embodiment of a metal powder bed additive manufacturing system of the present application, Figure 3 This is a structural schematic diagram from another perspective of an embodiment of the metal powder bed additive manufacturing system of the present application.

[0029] like Figures 1 to 3 As shown, the metal powder bed additive manufacturing system includes a molding cavity 10, wherein a printing surface 101 is arranged on the bottom surface of the molding cavity 10, and the printing surface 101 is used to carry the printed part during the printing process; a lens mounting surface 102 is arranged on the top surface of the molding cavity 10, specifically, a laser lens can be installed on the top of the molding cavity 10, and laser operation can be performed on the printing surface 101 through a through hole penetrating the lens mounting surface 102.

[0030] The side wall of the molding cavity 10 further includes an air inlet surface 103 and an air outlet surface 104 which are arranged opposite to each other, wherein the air inlet surface 103 is provided with a stratospheric air inlet channel 105, a suppression layer air inlet channel 106 and a clean air layer air inlet channel 107 in sequence from bottom to top;

[0031] The wind outlet surface 104 is provided with a stratospheric wind outlet channel 108, a damping layer wind outlet channel 109 and a clean air layer wind outlet channel 110 for respectively conducting out the wind blown in by the stratospheric wind inlet channel 105, the damping layer wind inlet channel 106 and the clean air layer wind inlet channel 107.

[0032] The metal powder bed additive manufacturing system also includes a blowing device (not shown in the figure), which is used to blow air into the molding cavity 10 through the stratospheric air inlet channel 105, the suppression layer air inlet channel 106 and the clean air layer air inlet channel 107.

[0033] It can be understood that through the cooperation of the stratospheric air inlet channel 105 and the stratospheric air outlet channel 108, the suppression layer air inlet channel 106 and the suppression layer air outlet channel 109, and the clean air layer air inlet channel 107 and the clean air layer air outlet channel 110, a three-layer wind field arranged in sequence from bottom to top can be formed inside the molding cavity 10.

[0034] The design of the three-layer wind field is described in detail below, wherein the stratospheric air inlet channel 105 and the clean air layer air inlet channel 107 are extended along the first direction x, the first direction x is the direction from the air inlet surface 103 to the air outlet surface 104, and the first direction x is parallel to the printing format 101. Correspondingly, the stratospheric air outlet channel 108 is arranged at the orthographic projection of the stratospheric air inlet channel 105 on the air outlet surface 104; the clean air layer air outlet channel 110 is arranged at the orthographic projection of the clean air layer air inlet channel 107 on the air outlet surface 104.

[0035] Since the extension directions of the stratospheric air inlet channel 105 and the clean air layer air inlet channel 107 are parallel to the printing format 101, parallel wind fields can be formed at the bottom and top of the molding cavity 10 respectively. The parallel wind field at the bottom is arranged next to the printing format 101, and is used to blow out the by-products generated during the printing process and discharge them through the stratospheric air outlet channel 108; the parallel wind field at the top is arranged next to the laser lens, and is used to prevent the by-products of the printing process from contaminating the lens and ensuring the printing quality.

[0036] Specifically, in this embodiment, the molding cavity 10 includes a pair of first guide plates 111 and a pair of second guide plates 112 arranged on the air inlet surface 103 and penetrating the side wall of the molding cavity 10, and the gap between the pair of first guide plates 111 forms a stratospheric air inlet channel 105, and the gap between the pair of second guide plates 112 forms a clean air layer air inlet channel 107. Of course, in other embodiments, the stratospheric air inlet channel 105 and the clean air layer air inlet channel 107 can also be implemented in other commonly used ways in the art, and the effects of this embodiment can be achieved.

[0037] In order to increase the air pressure of the parallel wind field at the top of the molding cavity 10 to achieve the best purging effect on the laser lens, in this embodiment, the molding cavity 10 also includes a flow limiting plate 113 arranged at the inner end of the second flow guide plate 112, and the flow limiting plate 113 extends from the inner end of the second flow guide plate 112 toward the other second flow guide plate 112 to increase the outlet wind pressure of the clean air layer inlet channel 107. It can be understood that the outlet area of ​​the clean air layer inlet channel 107 is reduced by the action of a pair of flow limiting plates 113, thereby increasing the gas flow rate and improving the purging effect.

[0038] In order to form a stable and uniform wind wall on the printing format 101, please refer to Figure 2 In this embodiment, the molding chamber 10 further includes a plurality of air guide plates 114 arranged between the inner ends of a pair of first air guide plates 111. The plurality of air guide plates 114 are arranged at intervals to separate the outlet of the stratospheric air inlet channel 105 into a plurality of relatively independent outlets, so that the wind entering the molding chamber 10 from the stratospheric air inlet channel 105 can be evenly divided into a plurality of strands, thereby ensuring the uniformity and stability of the wind field on the printing surface 101.

[0039] In order to avoid mutual interference between the parallel wind fields inside the molding cavity 10 and improve the stability of the top and bottom parallel wind fields, in the present embodiment, the air inlet channel outlet 1062 of the flow suppression layer air inlet channel 106 is set to point to the second direction y, and the second direction y is inclined relative to the first direction x toward the printing format 101. Correspondingly, the air outlet channel inlet 1091 of the flow suppression layer air outlet channel 109 is arranged below the direct projection of the air inlet channel outlet 1062 of the flow suppression layer air inlet channel 106 on the air outlet surface 104.

[0040] Through the cooperation of the flow suppression layer air inlet channel 106 and the flow suppression layer air outlet channel 109, a downward inclined flow suppression wind field can be formed in the middle of the molding cavity 10. The flow suppression wind field suppresses the parallel wind field at the bottom of the molding cavity 10 to the bottom, suppresses the gas turbulence inside the cavity, avoids the attenuation of the wind speed of the parallel wind field, and avoids the upward movement of smoke and dust, thereby ensuring the stability of the parallel wind field next to the printing format 101 and the laser lens, and improving the quality reliability of the print.

[0041] Specifically, see Figure 1 and Figure 2 The molding cavity 10 includes an air inlet cover 115 covered on the air inlet surface 103. The air inlet cover 115 is located between the clean air layer air inlet channel 107 and the stratospheric air inlet channel 105, and a flow suppression layer air inlet channel 106 is formed inside. The air inlet channel inlet 1061 of the flow suppression layer air inlet channel 106 is located on the air inlet surface 103 and runs through the side wall of the molding cavity 10, and the air inlet channel outlet 1062 is arranged on the air inlet cover 115.

[0042] Specifically, in this embodiment, the air inlet cover 115 includes a pair of side panels 1151 arranged opposite to each other, a top plate 1152 respectively located between the top, middle and lower parts of the pair of side panels 1151, an air inlet plate 1153 and a bottom plate 1154, the air inlet plate 1153 and the bottom plate 1154 are arranged obliquely relative to the printing format 101, and a plurality of air inlet channel outlets 1062 of the flow suppression layer air inlet channel 106 are evenly arranged on the lower area of ​​the air inlet plate 1153 and the bottom plate 1154.

[0043] Based on the above scheme, the air inlet channel outlet 1062 of the flow suppression layer air inlet channel 106 is densely arranged, and the air outlet surface 104 area is maximized, so as to even out the gas flow rate at the air inlet of the flow suppression layer, form a stable wind wall for the printing format 101 inside the molding cavity 10 and the laser lens space, and suppress the gas turbulence inside the cavity.

[0044] In one embodiment, the extension direction of the air inlet channel outlet 1062 of the flow suppression layer air inlet channel 106, that is, the second direction y, can be at an angle of 5 to 30 degrees with the first direction x, which can be achieved by adjusting the inclination angles of the air inlet plate 1153 and the bottom plate 1154 accordingly, thereby ensuring the optimal flow suppression effect.

[0045] In order to optimize the guide effect of the flow suppression layer air inlet channel 106, in the present embodiment, the air inlet channel inlet 1061 of the flow suppression layer air inlet channel 106 includes a horizontal flow section 10611 and a guide section 10612 arranged in sequence, the bottom side of the guide section 10612 is inclined toward the printing format 101, and the top plate 1152 is inclined toward the printing format 101 and is parallel to the bottom side of the guide section 10612, thereby guiding the incoming air to the air inlet plate 1153 and the bottom plate 1154.

[0046] In order to maximize the wind in the flow-suppressing wind field out of the molding cavity 10, in the present embodiment, the molding cavity 10 also includes an air outlet hood 116 arranged on the air outlet surface 104, and a flow-suppressing layer air outlet channel 109 is formed between the air outlet hood 116 and the air outlet surface 104, and an air outlet channel inlet 1091 of the flow-suppressing layer air outlet channel 109 is arranged at the bottom end of the air outlet hood 116, and the air outlet channel outlet 1092 is located on the air outlet surface 104 and is arranged through the side wall of the molding cavity 10.

[0047] Based on the above scheme, the flow suppression wind field can enter the interior of the air outlet hood 116 from the bottom of the air outlet hood 116 and finally be discharged from the outlet on the air outlet surface 104, wherein the height of the bottom of the air outlet hood 116 is lower than the bottom of the air inlet hood 115.

[0048] The metal powder bed additive manufacturing system of the above-mentioned embodiments ensures the stability and wind speed of the parallel wind field beside the printing format 101 and the laser lens through a three-layer wind field design, avoids flocculation inside the molding cavity 10, blows and collects printing by-products as much as possible, prevents the printing format 101 and the laser lens from being contaminated, improves the quality reliability of the printed parts, and enhances the market competitiveness of the products.

[0049] It is obvious to those skilled in the art that the present application is not limited to the details of the exemplary embodiments described above, and that the present application can be implemented in other specific forms without departing from the spirit or essential features of the present application. Therefore, the embodiments should be regarded as exemplary and non-limiting in all respects, and the scope of the present application is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present application. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0050] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A metal powder bed additive manufacturing system based on a three-layer wind field, characterized in that: include: A molding cavity, wherein the bottom surface is provided with a printing surface, the top surface is provided with a lens mounting surface, and the side wall includes an air inlet surface and an air outlet surface which are arranged opposite to each other, wherein the air inlet surface is sequentially arranged with a stratospheric air inlet channel, a flow suppression layer air inlet channel and a clean air layer air inlet channel from bottom to top, wherein the stratospheric air inlet channel and the clean air layer air inlet channel are extended in a first direction, and an air inlet channel outlet of the flow suppression layer air inlet channel is arranged to point to a second direction; A blowing device, used for blowing air into the cavity of the molding cavity through the stratospheric air inlet channel, the suppression layer air inlet channel and the clean air layer air inlet channel; Among them, the wind outlet surface is arranged with a stratospheric air outlet channel, a stratospheric air outlet channel and a clean air layer air outlet channel, which are respectively used to discharge the wind blown in by the stratospheric air inlet channel, the stratospheric air inlet channel and the clean air layer air inlet channel; the first direction is the direction in which the air inlet surface points to the air outlet surface, and the first direction is parallel to the printing format; the second direction is inclined toward the printing format direction relative to the first direction.

2. The metal powder bed additive manufacturing system according to claim 1, characterized in that: The molding cavity further includes a pair of first guide plates and a pair of second guide plates arranged on the air inlet surface and penetrating the side wall of the molding cavity. The gap between the pair of first guide plates forms the stratospheric air inlet channel, and the gap between the pair of second guide plates forms the clean air layer air inlet channel.

3. The metal powder bed additive manufacturing system according to claim 2, characterized in that: The molding cavity further includes a flow limiting plate arranged at the inner end of the second guide plate, and the flow limiting plate extends from the inner end of the second guide plate toward another second guide plate to increase the fluid velocity at the outlet of the clean air layer air inlet channel.

4. The metal powder bed additive manufacturing system according to claim 2, characterized in that: The molding cavity further includes a plurality of air guide plates arranged between the inner ends of a pair of the first air guide plates, and the plurality of air guide plates are arranged at intervals to separate the outlet of the stratospheric air inlet channel into a plurality of relatively independent outlets.

5. The metal powder bed additive manufacturing system according to claim 1, characterized in that: The stratospheric air outlet channel is arranged at the orthogonal projection of the stratospheric air inlet channel on the air outlet surface; the clean air layer air outlet channel is arranged at the orthogonal projection of the clean air layer air inlet channel on the air outlet surface; the air outlet channel inlet of the suppression layer air outlet channel is arranged at the orthogonal projection of the air inlet channel outlet of the suppression layer air inlet channel below the orthogonal projection of the air outlet surface.

6. The metal powder bed additive manufacturing system according to claim 1, characterized in that: The molding cavity also includes an air inlet hood arranged on the air inlet surface, the air inlet hood is located between the clean air layer air inlet channel and the stratospheric air inlet channel, and the suppression layer air inlet channel is formed inside, the air inlet channel inlet of the suppression layer air inlet channel is located on the air inlet surface and penetrates the side wall of the molding cavity, and the air inlet channel outlet is arranged on the air inlet hood.

7. The metal powder bed additive manufacturing system according to claim 6, characterized in that: The air inlet hood includes a pair of side panels arranged opposite to each other, a top plate, an air inlet plate and a bottom plate respectively located between the top, middle and lower parts of the pair of side panels, the air inlet plate and the bottom plate are inclined relative to the printing format, and a plurality of air inlet channel outlets are evenly arranged on at least a partial area of ​​the air inlet plate and the bottom plate.

8. The metal powder bed additive manufacturing system according to claim 7, characterized in that: The air inlet inlet of the flow suppression layer air inlet channel includes a horizontal flow section and a guide section arranged in sequence, the bottom side of the guide section is inclined toward the printing format, and the top plate is inclined toward the printing format and parallel to the bottom side of the guide section.

9. The metal powder bed additive manufacturing system according to claim 1, characterized in that: The molding cavity also includes an air outlet hood arranged on the air outlet surface, and the flow suppression layer air outlet channel is formed between the air outlet hood and the air outlet surface, the air outlet channel inlet of the flow suppression layer air outlet channel is arranged at the bottom end of the air outlet hood, and the air outlet channel outlet is located on the air outlet surface and runs through the side wall of the molding cavity.

10. The metal powder bed additive manufacturing system according to any one of claims 1 to 9, characterized in that: The second direction forms an angle of 5 to 30 degrees with the first direction.

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