Rotary 3D printing system and printing method

Abstract

The application provides a rotary 3D printing system and a printing method, which comprises a mounting frame, a rotary printing table, which is arranged on the mounting frame in a pivotable manner, a powder forming cavity, which is arranged on a printing reference platform, a powder recycling cavity, which is arranged on the printing reference platform, a forming substrate, which is arranged in the powder forming cavity and extends along a circumferential arc line of the rotary printing table, a substrate driving device, which comprises a lifting plate block for bearing the forming substrate and a driver for driving the lifting plate block to move up and down, a powder supply bin, which is arranged on the mounting frame and above the rotary printing table, a laser device, which is arranged on the mounting frame and above the rotary printing table, and a powder spreading mechanism, which comprises a scraper mounting frame and a scraper. The application can continuously perform the powder spreading operation and the laser scanning and sintering operation synchronously, the powder spreading uniformity is good, the total powder spreading time is short, and the 3D printing efficiency is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of 3D printing additive manufacturing technology, and in particular to a rotary 3D printing system and printing method. Background Technology

[0002] Traditional SLS, SLM, and EBM devices are all controlled by a computer control system. The powder material is spread evenly on the substrate through a 3D printing powder feeding system. Then, an energy source (usually a laser with a galvanometer or an electron beam) moves along the X and Y axes. During the movement, the energy source sinters the powder material spread on the substrate. After sintering one layer, the substrate descends by one layer thickness, and then another layer of powder is spread and sintered again. Finally, the solid is obtained by layering the consumables on the substrate.

[0003] Most of the 3D printing devices disclosed in the existing technology are based on the above principle. They first spread the material powder on the substrate and then use an energy source to sinter the powder material. The powder spreading is not uniform, the total powder spreading time is long, and the overall efficiency is low. Summary of the Invention

[0004] In view of the shortcomings of the prior art described above, the technical problem to be solved by the present invention is to provide a rotary 3D printing system and printing method that enables the powder spreading operation and the laser scanning sintering operation to be carried out simultaneously and continuously, resulting in good powder spreading uniformity of the powder spreading mechanism, short total powder spreading time, and greatly improving 3D printing efficiency.

[0005] To address the aforementioned technical problems, this invention provides a rotary 3D printing system, comprising:

[0006] Mounting rack;

[0007] A rotary printing table is mounted on a mounting frame with its top surface forming a printing reference platform.

[0008] The powder forming cavity is located on the printing reference platform and extends along the circumferential arc of the rotary printing table.

[0009] The powder recovery chamber is located on the printing reference platform, and the powder recovery chamber and the powder forming chamber are arranged adjacent to each other along the circumference of the rotary printing table.

[0010] The lifting molding substrate is located inside the powder molding cavity and extends along the circumferential arc of the rotary printing table. The molding substrate is used to support the product.

[0011] The substrate driving device includes a lifting plate that carries the molded substrate and a driver that drives the lifting plate to move up and down. The lifting plate is located in the powder forming cavity, and the shape of the lifting plate is adapted to the shape of the powder forming cavity. The driver rotates with the fixed axis of the rotary printing table.

[0012] The powder supply hopper is located on the mounting frame and above the rotary printing stage to release the powder it stores onto the printing reference platform.

[0013] A laser device is mounted on a mounting frame and positioned above a rotary printing stage to project a laser beam onto the molding substrate.

[0014] The powder spreading mechanism includes a scraper mounting frame and a powder scraper. The scraper mounting frame is mounted on the mounting frame, and the powder scraper is mounted on the scraper mounting frame. The powder scraper is located above the rotary printing stage and extends radially along the rotary printing stage. The powder scraper is used to scrape the powder on the molding substrate and push excess powder into the powder recovery chamber.

[0015] Preferably, the scraper mounting bracket includes a support column and a cantilever rod for mounting the scraper blade. The support column is spaced through the center of the rotary printing table and is located on the mounting bracket, while the cantilever rod is located on the support column.

[0016] Preferably, the cantilever rod extends radially along the rotary printing table, and the radial inner end of the cantilever rod is fixed to the support column.

[0017] Preferably, the projection position of the laser device on the molding substrate is recorded as the irradiation position, the projection position of the powder supply hopper on the molding substrate is recorded as the powder falling position, and the projection position of the powder scraper on the molding substrate is recorded as the powder scraping position. The powder falling position, the powder scraping position, and the irradiation position are arranged sequentially along the rotation direction of the rotary printing table.

[0018] Preferably, the driver includes a servo motor fixedly connected to the rotary printing table and a lead screw driven by the servo motor, with the lead screw threaded through the lifting plate.

[0019] Preferably, the powder supply hopper includes a storage container, the bottom of which has a powder outlet, and a switch valve is provided on the powder outlet.

[0020] Preferably, the cross-section of the storage container gradually decreases from top to bottom.

[0021] Preferably, the powder forming cavity is fan-shaped, and the angle corresponding to the arc-shaped extension trajectory of the powder forming cavity is greater than 180 degrees.

[0022] Preferably, the top surface of the rotary printing stage has concentrically arranged outer and inner convex edges, which together define the printing reference platform into an annular shape.

[0023] The present invention also provides a printing method using the aforementioned rotary 3D printing system, comprising the following steps:

[0024] The powder supply hopper releases the powder it stores onto the printing reference platform according to a preset dispensing amount;

[0025] The rotary printing table begins to rotate in the preset direction. During the rotation, the powder scraper spreads the powder evenly on the upper surface of the molding substrate.

[0026] When the molded substrate covered with powder is rotated to a position below the laser device, the laser device begins to scan and sinter the powder.

[0027] When the scraper passes over the powder forming chamber and is positioned above the powder recovery chamber, it pushes excess powder into the powder recovery chamber. At the same time, the driver causes the lifting plate to descend one printing layer, and the forming substrate moves synchronously with the lifting plate. Then, the powder supply hopper releases powder for the second time, and the rotary 3D printing system enters the printing process for the second layer. This cycle continues until the product is formed.

[0028] As described above, the rotary 3D printing system and printing method of the present invention have the following beneficial effects: The mounting frame serves as the installation, layout, and load-bearing structure for the rotary 3D printing system, providing installation positions for components and mechanisms of the rotary 3D printing system other than the mounting frame. The rotary printing stage is generally cylindrical and can rotate around a fixed axis relative to the mounting frame. Since both the powder forming cavity and the powder recovery cavity are located on the printing reference platform, when the rotary printing stage rotates around its fixed axis, the powder forming cavity and the powder recovery cavity rotate with the rotary printing stage. The molding substrate is located within the powder forming cavity and extends along the circumferential arc of the rotary printing stage. When each printing layer is completed, the molding substrate will sink to the height of one printing layer. To achieve the lifting function of the molding substrate, the substrate driving device includes a lifting plate that supports the molding substrate and a driver that drives the lifting plate to move up and down. The lifting plate is located within the powder forming cavity, and the shape of the lifting plate is adapted to the shape of the powder forming cavity, so that the molding substrate rises and falls synchronously with the lifting plate. Furthermore, the driver rotates along with the fixed axis of the rotary print stage. This configuration allows the driver to move the lifting plate up and down during the rotation of the rotary print stage's fixed axis. The powder supply hopper is mounted on the mounting frame and remains relatively fixed. Located above the rotary print stage, the hopper releases its stored powder onto the printing reference platform when the printing reference platform is below it. The laser unit is also mounted on the mounting frame and remains relatively fixed. Located above the rotary print stage, the laser projects a beam onto the printing reference platform when the powder-coated substrate is below it, causing the powder to sinter and solidify. The doctor blade mounting bracket of the powder spreading mechanism is mounted on the mounting frame, keeping the doctor blade relatively fixed relative to the mounting frame. The doctor blade is located above the rotary print stage and extends radially along it, ensuring that the powder on the printing reference platform is evenly spread onto the printing reference platform. After the powder spreading operation is complete, the doctor blade pushes excess powder into the powder recovery chamber. Furthermore, a key innovation that deserves special emphasis is that the rotary printing stage maintains a constant rotation speed throughout the entire 3D printing process. Each time the powder scraper passes above the powder recovery chamber, the substrate driving device causes the molding substrate to settle to the height of one printing layer. Therefore, the rotary 3D printing system of this invention enables simultaneous and continuous powder spreading and laser scanning sintering operations. The rotary printing stage rotates on a fixed axis relative to the powder spreading mechanism, resulting in excellent powder spreading uniformity and a short total powder spreading time, significantly improving 3D printing efficiency. Attached Figure Description

[0029] Figure 1 The diagram shows the powder release of the rotary 3D printing system of the present invention.

[0030] Figure 2 Displayed as Figure 1 Top view of the rotary 3D printing system shown;

[0031] Figure 3 The image shown is a powder-laying printing diagram of the rotary 3D printing system of the present invention.

[0032] Figure 4 Displayed as Figure 3 Top view of the rotary 3D printing system shown;

[0033] Figure 5 The diagram shows the rotary printing table, powder forming chamber, and powder recovery chamber.

[0034] Component designation explanation

[0035] Detailed Implementation

[0036] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0037] It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings of this specification are merely for illustrative purposes to aid those skilled in the art and are not intended to limit the scope of the invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of the invention, should still fall within the scope of the technical content disclosed in this invention. Furthermore, the terms such as "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and are not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.

[0038] like Figure 1 , Figure 2 , Figure 3 as well as Figure 4 As shown, the present invention provides a rotary 3D printing system, comprising:

[0039] Mounting rack;

[0040] A rotary printing table 1 is mounted on a mounting frame with a fixed axis for rotation, and the top surface of the rotary printing table 1 forms a printing reference platform 11.

[0041] Powder forming cavity 2 is located on printing reference platform 11 and extends along the circumferential arc of rotary printing table 1.

[0042] Powder recovery chamber 3 is located on printing reference platform 11. Powder recovery chamber 3 and powder forming chamber 2 are arranged adjacent to each other along the circumference of rotary printing table 1.

[0043] The lifting molding substrate 4 is located in the powder molding cavity 2 and extends along the circumferential arc of the rotary printing table 1. The molding substrate 4 is used to support the product.

[0044] The substrate driving device 5 includes a lifting plate 51 that carries the above-mentioned molded substrate 4 and a driver 52 that drives the lifting plate 51 to move up and down. The lifting plate 51 is located in the powder forming cavity 2. The shape of the lifting plate 51 is adapted to the shape of the powder forming cavity 2. The driver 52 rotates with the fixed axis rotation of the rotary printing table 1.

[0045] The powder supply chamber 6 is mounted on the mounting frame and located above the rotary printing stage 1 to release the powder stored therein onto the printing reference platform 11.

[0046] Laser device 7 is mounted on the mounting frame and located above the rotary printing table 1 to project a laser beam onto the molding substrate 4.

[0047] The powder spreading mechanism 8 includes a scraper mounting frame 81 and a scraper blade 82. The scraper mounting frame 81 is mounted on the mounting frame, and the scraper blade 82 is mounted on the scraper mounting frame 81. The scraper blade 82 is located above the rotary printing table 1 and extends radially along the rotary printing table 1. The scraper blade 82 is used to scrape the powder on the molding substrate 4 and push the excess powder into the powder recovery chamber 3.

[0048] In this invention, the aforementioned mounting frame (not shown) serves as the installation, layout, and load-bearing structure for the rotary 3D printing system, providing mounting positions for components and mechanisms of the rotary 3D printing system other than the mounting frame. The rotary printing stage 1 is generally cylindrical and can rotate around a fixed axis relative to the mounting frame. Since both the powder forming cavity 2 and the powder recovery cavity 3 are located on the printing reference platform 11, when the rotary printing stage 1 rotates around its fixed axis, the powder forming cavity 2 and the powder recovery cavity 3 rotate with the rotary printing stage 1. The molding substrate 4 is located within the powder forming cavity 2 and extends along the circumferential arc of the rotary printing stage 1. When each printing layer is completed, the molding substrate 4 will sink to the height of one printing layer. To achieve the lifting function of the molding substrate 4, the substrate driving device 5 includes a lifting plate 51 that supports the molding substrate 4 and a driver 52 that drives the lifting plate 51 to move up and down. The lifting plate 51 is located within the powder forming cavity 2, and the shape of the lifting plate 51 is adapted to the shape of the powder forming cavity 2, so that the molding substrate 4 rises and falls synchronously with the lifting plate 51. Furthermore, the driver 52 rotates along with the fixed axis of the rotary print stage 1. This configuration allows the driver 52 to drive the lifting plate 51 up and down during the rotation of the rotary print stage 1. The powder supply hopper 6 is mounted on the mounting frame and remains relatively fixed to it. The powder supply hopper 6 is located above the rotary print stage 1. When the printing reference platform 11 is below the powder supply hopper 6, the powder supply hopper 6 can release the powder it stores onto the printing reference platform 11. The laser device 7 (e.g., a laser scanning galvanometer) is mounted on the mounting frame and remains relatively fixed to it. The laser device 7 is located above the rotary print stage 1. When the powder-coated molding substrate 4 is below the laser device 7, the laser device 7 projects a beam onto the molding substrate 4, causing the powder to sinter and form the desired shape. The scraper mounting bracket 81 of the powder spreading mechanism 8 is mounted on the mounting frame, so that the scraper blade 82 is relatively fixed relative to the mounting frame. The scraper blade 82 is located above the rotary printing stage 1 and extends radially along the rotary printing stage 1, which can evenly spread the powder on the printing reference platform 11 onto the molding substrate 4. After the powder spreading operation is completed, the scraper blade 82 pushes the excess powder into the powder recovery chamber 3. In addition, an innovation that needs to be emphasized is that the rotary printing stage 1 is always rotating at a constant speed throughout the 3D printing process; whenever the scraper blade 82 passes above the powder recovery chamber 3, the substrate driving device 5 causes the molding substrate 4 to sink by the height of one printing layer.

[0049] Therefore, the rotary 3D printing system of the present invention enables the powder spreading operation and the laser scanning sintering operation to be carried out simultaneously and continuously. The rotary printing stage 1 rotates on a fixed axis relative to the powder spreading mechanism 8, which makes the powder spreading mechanism 8 have good powder spreading uniformity and short total powder spreading time, greatly improving the 3D printing efficiency.

[0050] To simplify the structure of the aforementioned scraper mounting bracket 81, the scraper mounting bracket 81 includes a support column 811 and a cantilever rod 812 for mounting the scraper blade 82. The support column 811 is spaced through the center of the rotary printing table 1 and is located on the mounting bracket, while the cantilever rod 812 is located on the support column 811.

[0051] Furthermore, in order to keep the aforementioned scraper blade 82 in an elevated state, the aforementioned cantilever rod 812 extends radially along the rotary printing table 1, and the radial inner end of the cantilever rod 812 is fixed to the support column 811.

[0052] To ensure that the powder spreading and laser scanning sintering operations can be performed synchronously and continuously, the projection position of the laser device 7 on the molding substrate 4 is designated as the irradiation position, the projection position of the powder supply hopper 6 on the molding substrate 4 is designated as the powder dropping position, and the projection position of the powder scraper 82 on the molding substrate 4 is designated as the powder scraping position. The powder dropping position, powder scraping position, and irradiation position are arranged sequentially along the rotation direction of the rotary printing table 1. Although the start time of the powder spreading operation is earlier than the start time of the laser scanning sintering operation, and the end time of the powder spreading operation is earlier than the end time of the laser scanning sintering operation, there is an overlap period between the total time of the powder spreading operation and the total time of the laser scanning sintering operation. The percentage of this overlap period relative to the total time of the powder spreading operation is relatively large, and the percentage of this overlap period relative to the total time of the laser scanning sintering operation is also relatively large.

[0053] To precisely control the up-and-down movement of the lifting plate 51, the driver 52 includes a servo motor 521 fixedly connected to the rotary printing table 1 and a lead screw 522 driven by the servo motor 521. The lead screw 522 is threaded through the lifting plate 51. Specifically, the rotary printing table 1 has a through hole 14 to avoid the lead screw 522. In this case, the lifting plate 51 is equivalent to the nut structure of the nut-lead screw mechanism, and the lead screw 522 is equivalent to the lead screw structure of the nut-lead screw mechanism.

[0054] For automated powder release, the powder supply chamber 6 includes a storage container with a powder outlet at the bottom, and a switching valve is installed on the outlet. The switching valve is communicatively connected to the industrial control computer of the rotary 3D printing system.

[0055] To control the amount of powder released, the cross-section of the aforementioned storage container gradually decreases from top to bottom. Specifically, the powder outlet is a flat orifice, and its length is parallel to the radial direction of the rotary printing stage 1.

[0056] To extend the overlap time between the powder spreading operation and the laser scanning sintering operation, the powder forming cavity 2 is fan-shaped, and the angle corresponding to the arc-shaped extension trajectory of the powder forming cavity 2 is greater than 180 degrees. In addition, the powder recovery cavity 3 is also fan-shaped, and the angle corresponding to the arc-shaped extension trajectory of the powder recovery cavity 3 is no greater than 45 degrees.

[0057] To prevent powder from falling off the rotary printing table 1 during the powder spreading process by the powder scraper 82, the top surface of the rotary printing table 1 has a concentrically arranged outer convex edge 12 and inner convex edge 13, which together define the printing reference platform 11 into a ring shape.

[0058] The present invention also provides a printing method using the above-described rotary 3D printing system, comprising the following steps:

[0059] The powder supply chamber 6 releases the powder stored in it onto the printing reference platform 11 according to the preset dispensing amount;

[0060] The rotary printing table 1 starts to rotate in the preset rotation direction. During the rotation, the powder scraper 82 spreads the powder evenly on the upper surface of the molding substrate 4.

[0061] When the molded substrate 4 with powder spread on it rotates to a position below the laser device 7, the laser device 7 begins to scan and sinter the powder.

[0062] When the scraper blade 82 passes over the powder forming chamber 2 and is positioned above the powder recovery chamber 3, the scraper blade 82 pushes excess powder into the powder recovery chamber 3. At the same time, the driver 52 drives the lifting plate 51 to descend one printing layer, and the forming substrate 4 moves synchronously with the lifting plate 51. Then, the powder supply hopper 6 releases powder for the second time, and the rotary 3D printing system enters the printing process of the second layer. This cycle continues until the product is formed.

[0063] The printing method of the present invention enables the powder spreading operation and the laser scanning sintering operation to be carried out simultaneously and continuously. The rotary printing stage 1 rotates on a fixed axis relative to the powder spreading mechanism 8, which makes the powder spreading mechanism 8 have good powder spreading uniformity and short total powder spreading time, greatly improving the 3D printing efficiency.

[0064] In summary, the rotary 3D printing system and method of this invention enable simultaneous and continuous powder spreading and laser scanning sintering operations, resulting in excellent powder spreading uniformity and short total powder spreading time, thus greatly improving 3D printing efficiency. Therefore, this invention effectively overcomes the various shortcomings of existing technologies and has high industrial application value.

[0065] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A rotary 3D printing system, characterized by, The device comprises: a mounting frame; a rotary printing platform (1) which is arranged on the mounting frame in a fixed-axle rotating manner, and the top surface of the rotary printing platform (1) forms a printing reference platform (11); a powder forming cavity (2) which is arranged on the printing reference platform (11), and the powder forming cavity (2) extends along the circumferential arc of the rotary printing platform (1); a powder recycling cavity (3) which is arranged on the printing reference platform (11), and the powder recycling cavity (3) and the powder forming cavity (2) are arranged adjacent to each other along the circumference of the rotary printing platform (1); a liftable forming substrate (4) which is located in the powder forming cavity (2) and extends along the circumferential arc of the rotary printing platform (1), and the forming substrate (4) is used for carrying products; a substrate driving device (5) which comprises a lifting plate block (51) carrying the forming substrate (4) and a driver (52) driving the lifting plate block (51) to move up and down, the lifting plate block (51) is located in the powder forming cavity (2), the shape of the lifting plate block (51) is matched with the shape of the powder forming cavity (2), and the forming substrate (4) is lifted synchronously with the lifting plate block (51); the driver (52) rotates with the rotary printing platform (1) in a fixed-axle rotating manner, and in the process of fixed-axle rotation of the rotary printing platform (1), the driver (52) can also drive the lifting plate block (51) to move up and down; a powder supply bin (6) which is arranged on the mounting frame and located above the rotary printing platform (1) to release the powder stored therein onto the printing reference platform (11); a laser device (7) which is arranged on the mounting frame and located above the rotary printing platform (1) to project a light beam onto the forming substrate (4); a powder spreading mechanism (8) which comprises a scraper mounting frame (81) and a powder scraper (82), the scraper mounting frame (81) is arranged on the mounting frame, the powder scraper (82) is arranged on the scraper mounting frame (81), the powder scraper (82) is located above the rotary printing platform (1) and extends along the radial direction of the rotary printing platform (1), and the powder scraper (82) is used for scraping the powder on the forming substrate (4) and pushing the excess powder into the powder recycling cavity (3); the scraper mounting frame (81) comprises a support column (811) and a cantilever rod (812) for mounting the powder scraper (82), the support column (811) is arranged at the center of the rotary printing platform (1) and on the mounting frame in a gap, and the cantilever rod (812) is arranged on the support column (811).

2. The rotary 3D printing system of claim 1, wherein: The cantilever rod (812) extends linearly along the radial direction of the rotary printing platform (1), and the radial inner end of the cantilever rod (812) is fixed to the support column (811).

3. The rotary 3D printing system of claim 1, wherein: The projection position of the laser device (7) on the forming substrate (4) is recorded as the irradiation position, the projection position of the powder supply bin (6) on the forming substrate (4) is recorded as the powder falling position, and the projection position of the powder scraper (82) on the forming substrate (4) is recorded as the powder scraping position, and the powder falling position, the powder scraping position and the irradiation position are arranged in sequence along the rotating direction of the rotary printing platform (1).

4. The rotary 3D printing system of claim 1, wherein: The driver (52) comprises a servo motor (521) fixedly connected with the rotary printing table (1) and a lead screw (522) in transmission connection with the servo motor (521), the lead screw (522) being threaded through the lifting plate (51).

5. The rotary 3D printing system of claim 1, wherein: The powder supply bin (6) comprises a storage container, a bottom of the storage container being provided with a powder outlet, and a switch valve being arranged on the powder outlet.

6. The rotary 3D printing system of claim 5, wherein: The cross section of the storage container gradually decreases from top to bottom.

7. The rotary 3D printing system of claim 1, wherein: The powder forming cavity (2) is in a fan shape, and an angle corresponding to an arc-shaped extension track of the powder forming cavity (2) is greater than 180 degrees.

8. The rotary 3D printing system of claim 1, wherein: The top end surface of the rotary printing table (1) is provided with an outer convex edge (12) and an inner convex edge (13) arranged concentrically, and the outer convex edge (12) and the inner convex edge (13) jointly define the printing reference platform (11) into a circular ring shape.

9. A printing method using the rotary 3D printing system according to any one of claims 1 to 8, characterized by, The method comprises the following steps: The powder supply bin (6) releases the powder stored therein to the printing reference platform (11) according to a preset release amount; The rotary printing table (1) starts to rotate in a preset rotation direction, and the powder scraper (82) spreads the powder on the upper surface of the forming substrate (4) during the rotation; When the forming substrate (4) with the spread powder rotates to the lower side of the laser device (7), the laser device (7) starts to scan and sinter the powder; When the powder scraper (82) is located above the powder recycling cavity (3) after passing through the powder forming cavity (2), the powder scraper (82) pushes the excess powder into the powder recycling cavity (3); at the same time, the driver (52) drives the lifting plate (51) to descend by one printing layer, the forming substrate (4) moves synchronously with the lifting plate (51), then the powder supply bin (6) releases the powder for the second time, and the rotary 3D printing system enters the printing operation process of the second layer, and the process is repeated until the product is formed.

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