Non-contact powder laying device and method for additive manufacturing

Abstract

The invention provides a non-contact powder laying device and method for additive manufacturing, and belongs to the technical field of additive manufacturing. The linear moving module is provided with a support, and the linear moving module can drive the support to move relative to the forming platform; the powder spreading module comprises a powder falling seat, a powder falling shaft and a powder bin; the powder suction seat is connected with the support, the powder suction seat comprises a powder suction port and a powder outlet, and the powder outlet is located above the powder suction port. The powder feeding device has the beneficial effects that the powder inlet and the powder falling opening are aligned to the two quadrant points of the containing cavity in the horizontal direction correspondingly, powder at the powder inlet can be prevented from falling to the powder falling opening through a gap between the powder falling shaft and the containing cavity when the powder falling shaft is in a static state, and the powder leakage phenomenon is avoided; and meanwhile, the powder falling shaft rotates in the direction from the air inlet to the powder falling opening through the bottom of the containing cavity, and powder falling into the containing cavity from the powder inlet can be effectively transferred to the powder falling opening.

Description

Technical Field

[0001] The present invention belongs to the technical field of additive manufacturing, and relates to a non-contact powder spreading device and method for additive manufacturing. Background Art

[0002] Existing laser selective melting technology usually uses contact-type powder spreading devices such as scrapers or powder spreading rollers to spread powder, but this powder spreading method often faces the following problems: First, during the powder spreading process, the powder spreading device is always in direct contact with the powder. If there is foreign matter on the surface of the scraper or powder spreading roller, it will directly affect the quality of the powder bed; second, the contact-type powder spreading device will produce a certain contact force on the powder bed and the formed part, and the contact force is inversely proportional to the thickness of the powder spreading layer. When the part is slightly warped and deformed, the contact force will increase significantly, resulting in greater powder spreading resistance, resulting in uneven powder spreading and affecting the quality of part forming; third, when the part is greatly warped and deformed, the powder spreading device will directly contact the part and interfere, resulting in local deformation, breakage or tool jamming of the part, resulting in a decrease in part quality or even the scrapping of the part.

[0003] In addition, as one of the future development trends of additive manufacturing technology, support-free forming technology also puts forward higher requirements on the powder spreading device. The flexible scraper used in the existing technology is difficult to meet the requirements of support-free forming technology. At the same time, the powder dropper is prone to problems such as powder leakage. Therefore, there is a large room for improvement. Summary of the invention

[0004] The purpose of the present invention is to address the above-mentioned problems existing in the prior art and to propose a non-contact powder spreading device and method for additive manufacturing.

[0005] The object of the present invention can be achieved by the following technical scheme: A non-contact powder spreading device for additive manufacturing, comprising:

[0006] Forming platform;

[0007] A linear moving module connected to the forming platform, wherein the linear moving module is provided with a bracket, and the linear moving module can drive the bracket to move relative to the forming platform;

[0008] A powder spreading module, comprising a powder dropping seat, a powder dropping shaft and a powder bin, wherein the powder dropping seat is connected to the bracket, the powder bin is connected to the powder dropping seat, the powder dropping seat is provided with a powder inlet, a containing chamber and a powder dropping port, the powder inlet, the containing chamber and the powder dropping port are integrally connected, the powder dropping shaft is rotatably connected to the powder dropping seat and is located in the containing chamber, the powder dropping shaft is provided with a powder dropping groove, the powder inlet and the powder dropping port are respectively aligned with two quadrants of the containing chamber in the horizontal direction, and the powder dropping shaft rotates from the powder inlet through the bottom of the containing chamber toward the powder dropping port;

[0009] A powder suction seat is connected to the bracket, and the powder suction seat comprises a powder suction port and a powder outlet, wherein the powder outlet is located above the powder suction port.

[0010] In the above-mentioned non-contact powder spreading device for additive manufacturing, the powder spreading module also includes a powder scraper, one end of which is connected to the powder dropping seat, and the other end of which is in contact with the powder dropping shaft and can extend into the powder dropping groove.

[0011] In the above-mentioned non-contact powder spreading device for additive manufacturing, the scraper includes a fixed part and a powder scraping part, the fixed part is connected to the powder dropping seat, the number of the powder scraping parts is at least two, each of the powder scraping parts is connected to the fixed part and in contact with the powder dropping shaft, and a powder scraping gap is formed between two adjacent powder scraping parts.

[0012] In the above-mentioned non-contact powder spreading device for additive manufacturing, the powder spreading module also includes a rotating bearing and a bearing seat, the bearing seat is connected to the powder dropping seat, and the end of the powder dropping shaft is rotatably connected to the bearing seat through the bearing.

[0013] In the above-mentioned non-contact powder spreading device for additive manufacturing, the powder spreading module also includes a sealing gasket, which is located between the end of the powder falling shaft and the rotating bearing, and the end of the powder falling shaft contacts the rotating bearing through the sealing gasket.

[0014] In the above-mentioned non-contact powder spreading device for additive manufacturing, the powder spreading module also includes a reducer and a motor, the reducer and the motor are fixed relative to the powder dropping seat, the powder dropping shaft is connected to the motor through the reducer, and the motor can drive the powder dropping shaft to rotate through the reducer.

[0015] In the above-mentioned non-contact powder spreading device for additive manufacturing, the powder suction seat is provided with a scraping knife seat, and the scraping knife seat is arranged on a side of the powder suction port close to the bracket.

[0016] In the above-mentioned non-contact powder spreading device for additive manufacturing, the height of the bottom of the accommodating chamber gradually increases from the lower quadrant point to the powder dropping port to form an anti-overflow portion.

[0017] In the above-mentioned non-contact powder spreading device for additive manufacturing,

[0018] Secondly, a non-contact powder spreading method for additive manufacturing includes the steps of:

[0019] S1: The linear motion module drives the bracket to move relative to the forming platform, thereby driving the powder spreading module and the powder suction seat to move;

[0020] S2: The powder spreading module drops the powder in the powder bin onto the forming platform, and forms a powder layer with a first thickness under the action of linear motion;

[0021] S3: The powder suction seat simultaneously sucks powder from the powder layer of the first thickness, so that the forming platform forms a powder layer of the second thickness after the powder is sucked, and the second thickness is 1 / 5-1 / 10 of the first thickness.

[0022] In the above-mentioned non-contact powder spreading method for additive manufacturing, in step S3, the powder layer having a first thickness is pre-leveled by a scraper seat provided on the powder suction seat.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. The powder inlet and the powder drop outlet are respectively aligned with the two quadrants of the accommodating chamber in the horizontal direction, which can prevent the powder at the powder inlet from falling to the powder drop outlet through the gap between the powder drop outlet and the accommodating chamber when the powder drop outlet shaft is in a stationary state, thereby avoiding powder leakage. At the same time, the powder drop outlet shaft rotates from the powder inlet through the bottom of the accommodating chamber toward the powder drop outlet, which can effectively transfer the powder that falls into the accommodating chamber from the powder inlet to the powder drop outlet.

[0025] 2. The non-contact powder spreading device for additive manufacturing pre-places excess powder through a powder dropping module, and uses a powder suction seat to absorb powder and spread the powder evenly, thereby realizing non-contact powder spreading.

[0026] 3. One end of the scraper is connected to the powder dropping seat and the other end of the scraper is in contact with the powder dropping shaft, thereby effectively cleaning the residual powder in the powder dropping groove and scraping the powder out of the powder dropping port to improve the powder dropping accuracy.

[0027] 4. A powder scraping gap is formed between two adjacent powder scraping parts to ensure that the powder scraper can effectively clean the residual powder in the powder dropping groove, and the powder can evenly fall from the powder scraping gap to the powder dropping port.

[0028] 5. The sealing gasket is located between the end of the powder dropping shaft and the rotating bearing. The end of the powder dropping shaft contacts the rotating bearing through the sealing gasket. The sealing gasket is used to seal and isolate the powder inside the powder dropping shaft to prevent the powder from affecting the bearing performance.

[0029] 6. A scraper seat is provided on the side of the powder suction port close to the bracket. As the bracket moves, the powder is pre-leveled before the powder suction seat sucks the powder, which effectively improves the powder suction accuracy.

[0030] 7. Since the distance between the non-contact powder spreading device for additive manufacturing and the surface of the powder layer can be up to 10 times the second thickness, even if the formed part is warped or deformed, the device will not come into direct contact with the formed part. This avoids the problem of conventional scrapers generating direct contact force on the formed part during the powder spreading process and causing damage to the part and causing it to displace and deform. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic structural diagram of the non-contact powder spreading device for additive manufacturing of the present invention.

[0032] Figure 2 An exploded view of the non-contact powder spreading device for additive manufacturing of the present invention.

[0033] Figure 3 It is a top view of the non-contact powder spreading device for additive manufacturing of the present invention.

[0034] Figure 4 for Figure 3 Cross-sectional view from AA perspective.

[0035] Figure 5 for Figure 4 An enlarged view of the powder suction seat.

[0036] Figure 6 It is a structural schematic diagram of the powder spreading module of the present invention.

[0037] Figure 7 It is an exploded view of the powder spreading module of the present invention.

[0038] In the figure, 100, forming platform; 200, linear moving module; 210, bracket; 300, powder spreading module; 310, powder dropping seat; 311, powder inlet; 312, accommodating chamber; 313, powder dropping port; 314, anti-overflow part; 320, powder dropping shaft; 321, powder dropping trough; 330, powder bin; 340, powder scraper; 341, fixing part; 342, powder scraper part; 350, rotating bearing; 360, bearing seat; 370, sealing gasket; 380, reducer; 390, motor; 400, powder suction seat; 410, powder suction port; 420, powder outlet; 430, scraper seat. DETAILED DESCRIPTION

[0039] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0040] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0041] In addition, in the present invention, descriptions such as "first", "second", "one", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0042] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0043] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0044] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0045] like Figure 1-Figure 7 As shown, a non-contact powder spreading device for additive manufacturing includes: a forming platform 100, a linear moving module 200, a powder spreading module 300 and a powder suction seat 400.

[0046] The linear moving module 200 is connected to the forming platform 100 , and the linear moving module 200 is provided with a bracket 210 . The linear moving module 200 can drive the bracket 210 to move relative to the forming platform 100 .

[0047] Among them, the powder laying module 300 includes a powder dropping seat 310, a powder dropping shaft 320 and a powder bin 330, the powder dropping seat 310 is connected to the bracket 210, the powder bin 330 is connected to the powder dropping seat 310, the powder dropping seat 310 is provided with a powder inlet 311, a accommodating chamber 312 and a powder dropping port 313, the powder inlet 311, the accommodating chamber 312 and the powder dropping port 313 are connected as a whole, the powder dropping shaft 320 is rotatably connected to the powder dropping seat 310 and is located in the accommodating chamber 312, the powder dropping shaft 320 is provided with a powder dropping groove 321, the powder inlet 311 and the powder dropping port 313 are respectively aligned with the two quadrants of the accommodating chamber 312 in the horizontal direction, and the powder dropping shaft 320 rotates from the powder inlet 311 through the bottom of the accommodating chamber 312 toward the powder dropping port 313.

[0048] The powder suction seat 400 is connected to the bracket 210 , and the powder suction seat 400 includes a powder suction port 410 and a powder outlet 420 , and the powder outlet 420 is located above the powder suction port 410 .

[0049] In this embodiment, the powder inlet 311 and the powder drop outlet 313 are respectively aligned with the two quadrants of the accommodating chamber 312 in the horizontal direction, which can prevent the powder at the powder inlet 311 from falling to the powder drop outlet 313 through the gap between the powder drop outlet 320 and the accommodating chamber 312 when the powder drop outlet shaft 320 is in a stationary state, thereby avoiding powder leakage. At the same time, the powder drop outlet 313 rotates from the powder inlet 311 through the bottom of the accommodating chamber 312 toward the powder drop outlet 313, which can effectively transfer the powder that falls into the accommodating chamber 312 from the powder inlet 311 to the powder drop outlet 313.

[0050] At the same time, the non-contact powder spreading device for additive manufacturing pre-places excess powder through the powder dropping module, and uses the powder suction seat 400 to absorb the powder and spread the powder evenly, thereby realizing non-contact powder spreading.

[0051] like Figure 1-Figure 7 As shown, based on the above embodiment, the powder spreading module 300 also includes a powder scraper 340, one end of which is connected to the powder dropping seat 310, and the other end of which is in contact with the powder dropping shaft 320 and can extend into the powder dropping groove 321.

[0052] Specifically, the scraper 340 is an elastic structure, and the scraper 340 is preset with elastic force to extend into the powder dropping groove 321 , that is, when the powder dropping shaft 320 rotates until the scraper 340 is aligned with the powder dropping groove 321 , the scraper 340 extends into the powder dropping groove 321 .

[0053] Specifically, the powder scraper 340 is located at the powder dropping opening 313 .

[0054] In this embodiment, one end of the scraper 340 is connected to the powder dropping seat 310 and the other end of the scraper 340 is in contact with the powder dropping shaft 320, thereby effectively cleaning the residual powder in the powder dropping groove 321 and scraping the powder out of the powder dropping port 313, thereby improving the powder dropping accuracy.

[0055] like Figure 1-Figure 7 As shown, on the basis of the above embodiment, the scraper 340 includes a fixed part 341 and a scraper part 342, the fixed part 341 is connected to the powder dropping seat 310, the number of the scraper parts 342 is at least two, each of the scraper parts 342 is connected to the fixed part 341 and in contact with the powder dropping shaft 320, and a scraper gap is formed between two adjacent scraper parts 342.

[0056] In this embodiment, a powder scraping gap is formed between two adjacent powder scraping portions 342 to ensure that the powder scraping knife 340 can effectively clean the residual powder in the powder dropping groove 321 while the powder can evenly fall from the powder scraping gap to the powder dropping port 313 .

[0057] like Figure 1-Figure 7 As shown, based on the above embodiment, the powder spreading module 300 also includes a rotating bearing 350 and a bearing seat 360, the bearing seat 360 is connected to the powder dropping seat 310, and the end of the powder dropping shaft 320 is rotatably connected to the bearing seat 360 through the bearing.

[0058] In this embodiment, the end of the powder dropping shaft 320 is rotatably connected to the bearing seat 360 through a bearing, so that a certain gap is formed between the middle of the powder dropping shaft 320 and the accommodating cavity 312 to prevent direct sliding friction between the two and increase the service life.

[0059] like Figure 1-Figure 7 As shown, based on the above embodiment, the powder spreading module 300 also includes a sealing gasket 370, which is located between the end of the powder falling shaft 320 and the rotating bearing 350, and the end of the powder falling shaft 320 contacts the rotating bearing 350 through the sealing gasket 370.

[0060] Specifically, the sealing gasket 370 may be felt.

[0061] In this embodiment, the sealing gasket 370 is located between the end of the powder dropping shaft 320 and the rotating bearing 350. The end of the powder dropping shaft 320 contacts the rotating bearing 350 through the sealing gasket 370. The sealing gasket 370 is used to seal and isolate the powder inside the powder dropping shaft 320 to prevent the powder from affecting the bearing performance.

[0062] like Figure 1-Figure 7As shown, based on the above embodiment, the powder spreading module 300 also includes a reducer 380 and a motor 390, the reducer 380 and the motor 390 are fixed relative to the powder dropping seat 310, the powder dropping shaft 320 is connected to the motor 390 through the reducer 380, and the motor 390 can drive the powder dropping shaft 320 to rotate through the reducer 380.

[0063] In this embodiment, the motor 390 can drive the powder dropping shaft 320 to rotate through the reducer 380 to provide a power source.

[0064] like Figure 1-Figure 7 As shown, on the basis of the above embodiment, the powder suction seat 400 is provided with a scraping knife seat 430 , and the scraping knife seat 430 is arranged on a side of the powder suction port 410 close to the bracket 210 .

[0065] Specifically, in order to increase the service life of the scraper seat 430 , a layer of wear-resistant material may be added to the surface of the scraper seat 430 .

[0066] In this embodiment, a scraper seat 430 is provided on one side of the powder suction port 410 close to the bracket 210 , and the powder is pre-leveled before the powder suction seat 400 sucks the powder as the bracket 210 moves, thereby effectively improving the powder suction accuracy.

[0067] like Figure 1-Figure 7 As shown, based on the above embodiment, the height of the bottom of the accommodating cavity 312 gradually increases from the lower quadrant point to the powder dropping port 313 to form an anti-overflow portion 314.

[0068] In this embodiment, the anti-overflow portion 314 formed by the gradually increasing height of the bottom of the accommodating cavity 312 from the lower quadrant point to the powder dropping port 313 can prevent the powder at the powder inlet 311 from falling to the powder dropping port 313 through the gap between the powder dropping shaft 320 and the accommodating cavity 312 when the powder dropping shaft 320 is in a stationary state, so as to concentrate the powder at the lower quadrant point, further avoiding the occurrence of powder leakage.

[0069] like Figure 1-Figure 7 As shown, a non-contact powder spreading method for additive manufacturing comprises the steps of:

[0070] S1: The linear moving module 200 drives the bracket 210 to move relative to the forming platform 100, thereby driving the powder spreading module 300 and the powder suction seat 400 to move;

[0071] S2: The powder spreading module 300 drops the powder in the powder bin 330 onto the forming platform 100, and a powder layer having a first thickness H1 is formed under the action of linear motion;

[0072] S3: The powder suction seat 400 simultaneously sucks powder from the powder layer with the first thickness H1, so that the forming platform 100 forms a powder layer with the second thickness H after the powder is sucked. The second thickness H is 1 / 5-1 / 10 of the first thickness H1.

[0073] In this embodiment, since the maximum distance between the non-contact powder spreading device for additive manufacturing and the surface of the powder layer can be up to 10 times the second thickness H, even if the formed part is warped or deformed, the device will not come into direct contact with the formed part. This avoids the problem of conventional scrapers generating direct contact force on the formed part during the powder spreading process and causing damage to the part, causing it to displace and deform.

[0074] like Figure 1-Figure 7 As shown, on the basis of the above embodiment, in step S3, the powder layer with a first thickness H1 is pre-leveled by the scraper seat 430 provided on the powder suction seat 400.

[0075] In this embodiment, a scraper seat 430 is provided on one side of the powder suction port 410 close to the bracket 210 , and the powder is pre-leveled before the powder suction seat 400 sucks the powder as the bracket 210 moves, thereby effectively improving the powder suction accuracy.

Claims

1. A non-contact powder spreading device for additive manufacturing, characterized in that: include: Forming platform; A linear moving module connected to the forming platform, wherein the linear moving module is provided with a bracket, and the linear moving module can drive the bracket to move relative to the forming platform; A powder spreading module, comprising a powder dropping seat, a powder dropping shaft and a powder bin, wherein the powder dropping seat is connected to the bracket, the powder bin is connected to the powder dropping seat, the powder dropping seat is provided with a powder inlet, a containing chamber and a powder dropping port, the powder inlet, the containing chamber and the powder dropping port are integrally connected, the powder dropping shaft is rotatably connected to the powder dropping seat and is located in the containing chamber, the powder dropping shaft is provided with a powder dropping groove, the powder inlet and the powder dropping port are respectively aligned with two quadrants of the containing chamber in the horizontal direction, and the powder dropping shaft rotates from the powder inlet through the bottom of the containing chamber toward the powder dropping port; A powder suction seat is connected to the bracket, and the powder suction seat comprises a powder suction port and a powder outlet, wherein the powder outlet is located above the powder suction port.

2. A non-contact powder spreading device for additive manufacturing according to claim 1, characterized in that: The powder spreading module also includes a powder scraper, one end of which is connected to the powder dropping seat, and the other end of which is in contact with the powder dropping shaft and can extend into the powder dropping groove.

3. A non-contact powder spreading device for additive manufacturing according to claim 2, characterized in that: The powder scraper includes a fixed part and a powder scraping part, the fixed part is connected to the powder dropping seat, the number of the powder scraping parts is at least two, each of the powder scraping parts is connected to the fixed part and contacts the powder dropping shaft, and a powder scraping gap is formed between two adjacent powder scraping parts.

4. A non-contact powder spreading device for additive manufacturing according to claim 1, characterized in that: The powder spreading module further comprises a rotating bearing and a bearing seat, wherein the bearing seat is connected to the powder dropping seat, and the end of the powder dropping shaft is rotatably connected to the bearing seat via the bearing.

5. A non-contact powder spreading device for additive manufacturing according to claim 4, characterized in that: The powder spreading module further includes a sealing gasket, which is located between the end of the powder dropping shaft and the rotating bearing, and the end of the powder dropping shaft contacts the rotating bearing through the sealing gasket.

6. A non-contact powder spreading device for additive manufacturing according to claim 1, characterized in that: The powder spreading module also includes a reducer and a motor, the reducer and the motor are fixed relative to the powder dropping seat, the powder dropping shaft is connected to the motor via the reducer, and the motor can drive the powder dropping shaft to rotate via the reducer.

7. A non-contact powder spreading device for additive manufacturing according to claim 1, characterized in that: The powder suction seat is provided with a scraping knife seat, and the scraping knife seat is arranged on a side of the powder suction port close to the bracket.

8. The non-contact powder spreading device for additive manufacturing according to claim 1, characterized in that: The height of the bottom of the accommodating cavity gradually increases from the lower quadrant point to the powder dropping port to form an overflow prevention portion.

9. A non-contact powder spreading method for additive manufacturing, characterized in that: Includes steps: S1: The linear motion module drives the bracket to move relative to the forming platform, thereby driving the powder spreading module and the powder suction seat to move; S2: The powder spreading module drops the powder in the powder bin onto the forming platform, and forms a powder layer with a first thickness under the action of linear motion; S3: The powder suction seat simultaneously sucks powder from the powder layer of the first thickness, so that the forming platform forms a powder layer of the second thickness after the powder is sucked, and the second thickness is 1 / 5-1 / 10 of the first thickness.

10. A non-contact powder spreading method for additive manufacturing according to claim 9, characterized in that: In step S3, the powder layer having a first thickness is pre-leveled by a leveling blade seat provided on the powder suction seat.

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