A powder spreading method and apparatus for multi-material printing

Abstract

This invention provides a powder spreading method and apparatus for multi-material printing, belonging to the field of additive manufacturing technology. The method includes the following steps: S1: forming a first powder layer; S2: forming a first powder printing layer and residual first powder within the printing area; S3: a powder suction component and a second powder spreading component operate synchronously to collect the residual first powder from step S2; S4: forming a second powder layer; S5: forming a second powder printing layer and residual second powder within the printing area; S6: a powder suction component and a first powder spreading component operate synchronously to collect the residual second powder from step S5; S7: repeating steps S1-S6 until the product printing is complete. This invention allows the powder spreading component to operate independently during powder spreading, and the powder suction component to operate synchronously with the un-powdered powder spreading component during powder suction. This avoids the risk of powder cross-contamination, improving the quality of laser-printed products. Furthermore, compared to powder spreading and suction components operating independently, it increases work efficiency.

Description

Technical Field

[0001] This invention belongs to the field of additive manufacturing technology and relates to a powder spreading method, particularly a powder spreading method and apparatus for multi-material printing. Background Technology

[0002] Powder bed fusion is the mainstream process in additive manufacturing. With the increasing demand for complex functional parts in industry, multi-material additive manufacturing has become an important development direction. Multi-material printing requires the precise placement of different powders onto the forming area using a powder spreading device. However, existing multi-material powder spreading devices have the following significant drawbacks in practical applications: First, the powder discharger suffers from powder leakage. During start-up, shutdown, or movement, the existing powder discharger is prone to unexpected powder leakage at the discharge port due to mechanical gaps, powder flowability, and equipment vibration. The leaked powder will cause powder contamination to the original powder bed.

[0003] Secondly, sharing a scraper leads to cross-contamination of powder. Currently, multi-material powder spreading often uses the same scraper to spread different powders. Because the powders are extremely fine and have strong adhesion, after the scraper spreads the first material, some powder inevitably remains on the blade. When the scraper continues to spread the second material, this residual powder mixes in, causing cross-contamination. This compromises the purity of the designed materials, leading to uncontrollable performance at the interface of the molded part, and even causing cracking.

[0004] Chinese patent CN202411605010.8 discloses a multi-material powder bed additive manufacturing equipment and its product preparation method. By setting two powder feeders and two scrapers, the risk of powder cross-contamination can be avoided to some extent. However, in this patent, the movement logic of the two powder feeders is always synchronous. When one powder feeder is in working state, although the other powder feeder is in non-working state, the synchronous operation of the two powder feeders causes powder leakage during the movement of the non-working powder feeder. This leaked powder mixes with the powder output by the working powder feeder, forming powder cross-contamination, which ultimately affects the product performance. Summary of the Invention

[0005] The purpose of this invention is to address the aforementioned problems in existing technologies by proposing a powder spreading method that can strictly avoid cross-contamination of powders and improve the performance of molded products.

[0006] The objective of this invention can be achieved through the following technical solution: a powder spreading method for multi-material printing, comprising: S1: The first powder spreading component moves horizontally from the first end to the second end of the printing area to form a first powder layer in the printing area; S2: The laser performs laser printing within the first powder layer along a preset trajectory, forming a first powder printing layer and residual first powder; S3: The powder suction component and the second powder spreading component move synchronously from the first end to the second end of the printing area in the horizontal direction, and the powder suction component absorbs the residual first powder in step S2. S4: The second powder spreading component moves horizontally from the second end to the first end of the printing area to form a second powder layer in the printing area; S5: The laser performs laser printing within the second powder layer along a preset trajectory, forming a second powder printing layer and residual second powder; S6: The powder suction component and the first powder spreading component move synchronously from the second end to the first end of the printing area in the horizontal direction, and the powder suction component absorbs the second powder remaining in step S5. S7: Repeat steps S1-S6 until the product printing is complete.

[0007] In the above-described powder spreading method for multi-material printing, regarding step S3, When the powder suction assembly is not equipped with a power drive structure, step S3 includes the following steps: S31: Drive the second drive motor, and through the meshing transmission between the second gear and the rack, cause the second moving plate to move in the horizontal direction. When the second moving plate comes into contact with the third moving plate, the second moving plate and the third moving plate move in the horizontal direction synchronously, so as to realize that the powder suction component and the second powder spreading component move in the horizontal direction synchronously. S32: When the third moving plate moves to a preset displacement at the first end of the printing area, the powder suction device is turned on to suck up the first powder remaining in step S2. Based on the function of the powder suction device, the second scraper never comes into contact with the first powder when it moves. S33: When the third moving plate moves to the second preset displacement from the printing area, the powder suction device is turned off, and at this time there is no residual first powder in the printing area; When the power drive structure is installed on the powder suction component, step S3 includes the following steps: S31: Drives the third drive motor, which, through the meshing transmission between the third gear and the rack, causes the third moving plate to move horizontally; at the same time, drives the second drive motor, which, through the meshing transmission between the second gear and the rack, causes the second moving plate to move horizontally, so that the powder suction component and the second powder spreading component move horizontally synchronously. S32: When the third moving plate moves to a preset displacement at the first end of the printing area, the powder suction device is turned on to suck up the first powder remaining in step S2. Based on the function of the powder suction device, the second scraper never comes into contact with the first powder when it moves. S33: When the third moving plate moves to the second preset displacement distance from the printing area, the powder suction device is turned off, and at this time there is no residual first powder in the printing area.

[0008] In the above-described powder spreading method for multi-material printing, regarding step S6, When the powder suction assembly is not equipped with a power drive structure, step S6 includes the following steps: S61: Drive the first drive motor, and through the meshing transmission between the first gear and the rack, cause the first moving plate to move in the horizontal direction. When the first moving plate comes into contact with the third moving plate, the first moving plate and the third moving plate move in the horizontal direction synchronously, so as to realize that the powder suction component and the first powder spreading component move in the horizontal direction synchronously. S62: When the third moving plate moves to the second end of the printing area at a preset displacement, the powder suction device is turned on to suck up the second powder remaining in step S5. Based on the function of the powder suction device, the first scraper never comes into contact with the second powder when it moves. S63: When the third moving plate moves to a preset displacement at the first end of the printing area, the powder suction device is turned off, and at this time there is no residual second powder in the printing area; When the power drive structure is installed on the powder suction component, step S6 includes the following steps: S61: Drive the third drive motor to move the third moving plate horizontally through the meshing transmission between the third gear and the rack; at the same time drive the first drive motor to move the first moving plate horizontally through the meshing transmission between the first gear and the rack, so as to realize that the powder suction component and the first powder spreading component move horizontally synchronously. S62: When the third moving plate moves to the second end of the printing area at a preset displacement, the powder suction device is turned on to suck up the second powder remaining in step S5. Based on the function of the powder suction device, the first scraper never comes into contact with the second powder when it moves. S63: When the third moving plate moves to a preset displacement at the first end of the printing area, the powder suction device is turned off, and at this time there is no residual second powder in the printing area.

[0009] The present invention also provides a powder spreading device for multi-material printing, comprising: A base plate having a printing area configured for powder laser printing, the printing area including a first end and a second end; A first powder spreading component, a second powder spreading component, and a powder suction component are slidably connected to the base plate. The first powder spreading component includes a first powder dropper, the second powder spreading component includes a second powder dropper, and the powder suction component includes a powder suction component. The planes where the powder dropper, the powder dropper, and the powder suction component are located are all higher than the plane of the printing area. During powder spreading, the first and second powder spreading components operate alternately and independently. During powder suction, the powder suction component operates alternately and synchronously with the first and second powder spreading components.

[0010] In the above-mentioned powder spreading device for multi-material printing, there are a first moving plate, a second moving plate and a third moving plate. The first moving plate is provided with a first powder dispenser and a first scraper, the second moving plate is provided with a second powder dispenser and a second scraper, and the third moving plate is provided with the powder suction device. The first scraper and the second scraper are arranged opposite to each other and are correspondingly connected to the side of the first moving plate and the second moving plate facing the third moving plate.

[0011] In the aforementioned powder spreading device for multi-material printing, when the powder suction device and the second powder discharge device move synchronously, there is a gap in the vertical direction between the plane where the lowest edge of the second scraper on the second moving plate is located and the residual first powder in the printing area; when the powder suction device and the first powder discharge device move synchronously, there is a gap in the vertical direction between the plane where the lowest edge of the first scraper on the first moving plate is located and the residual second powder in the printing area.

[0012] In the aforementioned powder spreading device for multi-material printing, when the powder suction device and the second powder dropper move synchronously, the powder suction device enters the printing area before the second powder dropper; when the powder suction device and the first powder dropper move synchronously, the powder suction device enters the printing area before the first powder dropper.

[0013] The powder spreading device for multi-material printing described above also includes: The rack is connected to the base plate, and the length direction of the rack is parallel to the powder spreading direction or the powder absorption direction; A first drive motor is mounted on a first movable plate, and the output end of the first drive motor is connected to a first gear that meshes with a rack. The second drive motor is mounted on the second movable plate, and the output end of the second drive motor is connected to a second gear that meshes with the rack.

[0014] The powder spreading device for multi-material printing described above also includes: The third drive motor is mounted on the third movable plate, and the output end of the third drive motor is connected to a third gear that meshes with the rack.

[0015] In the powder spreading device for multi-material printing described above, there are also two parallel slide rails connected to the base plate, a first slider connected to both ends of the first moving plate, a second slider connected to both ends of the second moving plate, and a third slider connected to both ends of the third moving plate, wherein the two first sliders, the two second sliders, and the two third sliders are respectively slidably connected to the corresponding slide rails.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The powder spreading device for multi-material printing provided by the present invention sets up the first powder spreading component, the second powder spreading component and the powder suction component separately. When spreading powder, the corresponding powder spreading component operates independently. When suctioning powder, the powder suction component operates synchronously with the powder spreading component where the other powder of the powder being suctioned is located. On the one hand, this avoids the risk of powder cross-contamination and improves the quality of laser printed products. On the other hand, compared with the control logic of the first powder spreading component, the powder suction component and the second powder spreading component operating independently, it improves the work efficiency.

[0017] (2) The first scraper and the second scraper are respectively connected to the side of the first moving plate and the second moving plate facing the powder suction component, so that when the powder is spread, the corresponding scraper is always located behind the powder drop port of the current powder dropper, thereby ensuring the reliability of the powder leveling. At the same time, when the powder suction component and the powder spreading component are running synchronously, the scraper on the current powder spreading component is located behind the powder suction component, ensuring that the scraper on the powder spreading component will not come into contact with the residual powder, thus avoiding cross-contamination of the powder. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the powder spreading device for multi-material printing according to the present invention.

[0019] Figure 2 This is a schematic diagram of the structure of the first powder spreading component in a preferred embodiment of the present invention.

[0020] Figure 3 This is a partial structural schematic diagram of the first powder spreading component in a preferred embodiment of the present invention.

[0021] Figure 4 This is a schematic diagram of the structure of the second powder spreading component in a preferred embodiment of the present invention.

[0022] Figure 5 This is a partial structural schematic diagram of the second powder spreading component in a preferred embodiment of the present invention.

[0023] In the picture, 100. Base plate; 110. Printing area; 111. First end; 112. Second end; 200. First powder spreading component; 210. First powder dropper; 211. First powder hopper; 212. First housing; 220. First moving plate; 221. First powder dropping trough; 230. First powder dropping motor; 240. First scraper; 250. First screw; 251. First receiving trough; 300. Second powder spreading component; 310. Second powder dropper; 311. Second powder hopper; 312. Second housing; 320. Second moving plate; 321. Second powder drop trough; 330. Second powder drop motor; 340. Second scraper; 350. Second screw; 351. Second receiving trough; 400. Powder suction component; 410. Powder suction device; 420. Third moving plate; 500, Drive assembly; 510, Rack; 520, First drive motor; 530, Second drive motor; 540, Third drive motor; 550, First gear; 560, Second gear; 570, Third gear; 580, Slide rail; 590, First slider; 5100, Second slider; 5200, Third slider. Detailed Implementation

[0024] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0025] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0026] like Figures 1 to 5 As shown, the present invention provides a powder spreading device for multi-material printing, comprising: A base plate 100 is provided thereon with a printing area 110 configured for powder laser printing, and the printing area 110 includes a first end 111 and a second end 112. A first powder-spreading assembly 200 and a second powder-spreading assembly 300 are slidably connected to the base plate 100, and a powder-absorbing assembly 400 is located between the first powder-spreading assembly 200 and the second powder-spreading assembly 300. The first powder-spreading assembly 200 includes a first powder dispenser 210, the second powder-spreading assembly 300 includes a second powder dispenser 310, and the powder-absorbing assembly 400 includes a powder-absorbing assembly 410. The planes where the powder outlets of the first powder dispenser 210, the second powder dispenser 310, and the powder-absorbing assembly 410 are located are all higher than the printing area 110. On the plane, when the powder discharge port of the first powder dispenser 210 slides from the first end 111 to the second end 112 of the printing area 110, the first powder can be spread; when the powder discharge port of the second powder dispenser 310 slides from the second end 112 to the first end 111 of the printing area 110, the second powder can be spread; when the powder suction port of the powder suction device 410 slides from the first end 111 to the second end 112 of the printing area 110, or from the second end 112 to the first end 111 of the printing area 110, the residual powder after the current laser printing can be sucked up.

[0027] It is worth mentioning that when the first powder is spread, the first powder spreading component 200 operates independently; when the residual first powder after laser printing is collected, the powder suction component 400 and the second powder spreading component 300 operate synchronously; when the second powder is spread, the second powder spreading component 300 operates independently; when the residual second powder after laser printing is collected, the powder suction component 400 and the first powder spreading component 200 operate synchronously.

[0028] In other words, when the first powder and the second powder are spread, the corresponding powder spreading components operate independently; when the residual first powder and second powder after laser printing are collected, the powder suction component 400 operates synchronously with the powder spreading component containing the other powder of the currently collected powder. In this way, even if powder leakage occurs in the powder spreading component that operates synchronously with the powder suction component 400, it will not be a problem, because the powder for the next layer of laser printing is the powder stored in the powder spreading component that operates synchronously with the powder suction component 400, so there is no risk of powder cross-contamination.

[0029] The present invention provides a powder spreading device for multi-material printing, wherein the first powder spreading component 200, the second powder spreading component 300, and the powder suction component 400 are set separately, and the corresponding powder spreading component operates independently during powder spreading, while the powder suction component 400 operates synchronously with the powder spreading component containing another powder of the powder currently being sucked. On the one hand, this avoids the risk of powder cross-contamination and improves the quality of laser printed products. On the other hand, compared with the control logic of the first powder spreading component 200, the powder suction component 400, and the second powder spreading component 300 operating independently, it improves work efficiency.

[0030] Preferably, the first powder spreading assembly 200 includes a first moving plate 220, and a first powder dispensing motor 230, a first powder dispenser 210, and a first scraper 240 connected to the first moving plate 220. The output end of the first powder dispensing motor 230 is connected to a first screw 250, wherein the first screw 250 extends into the first powder dispenser 210, and the first screw 250 is provided with a plurality of first receiving grooves 251 along the axial direction. The plurality of first receiving grooves 251 are arranged in a ring on the first screw 250. The first moving plate 220 is provided with first powder dispensing grooves 221 corresponding to the powder dispensing port position of the first powder dispenser 210. The second powder spreading assembly 300 includes a second moving plate 320, and a first powder dispensing motor 230, a first powder dispenser 210, and a first scraper 240 connected to the first moving plate 220. The moving plate 320 has a second powder-feeding motor 330, a second powder-feeding device 310, and a second scraper 340. The output end of the second powder-feeding motor 330 is connected to a second screw 350, which extends into the second powder-feeding device 310. The second screw 350 has multiple second receiving grooves 351 arranged in a ring along its axial direction. The second moving plate 320 has second powder-feeding grooves 321 corresponding to the powder-feeding port position of the second powder-feeding device 310. The first scraper 240 and the second scraper 340 are arranged opposite each other and are connected to the side of the first moving plate 220 and the second moving plate 320 facing the powder-absorbing assembly 400.

[0031] It is worth mentioning that the first powder dispenser 210 stores the first powder. The first powder dispensing motor 230 drives the first screw 250 to rotate, and the first powder in the first receiving groove 251 on the first screw 250 falls into the printing area 110 through the powder dispensing port on the first powder dispenser 210. The first scraper 240 scrapes the first powder in the printing area 110 to form the first powder layer. The second powder dispenser 310 stores the second powder. The second powder dispensing motor 330 drives the second screw 350 to rotate, and the second powder in the second receiving groove 351 on the second screw 350 falls into the printing area 110 through the powder dispensing port on the second powder dispenser 310. The second scraper 340 scrapes the second powder in the printing area 110 to form the second powder layer.

[0032] In this embodiment, the first scraper 240 and the second scraper 340 are respectively connected to the side of the first moving plate 220 and the second moving plate 320 facing the powder suction component 400, so that when the corresponding powder is spread, the corresponding scraper is always located behind the powder dispensing port of the current powder dispenser, thereby ensuring the reliability of powder leveling. At the same time, when the powder suction component 400 and the powder spreading component are running synchronously, the scraper on the current powder spreading component is located behind the powder suction component 400, ensuring that the scraper on the powder spreading component will not come into contact with residual powder, thus avoiding cross-contamination of powder.

[0033] More preferably, the first powder dispenser 210 includes a first powder hopper 211 and a first housing 212 that are interconnected, wherein the first powder hopper 211 is configured to store a first powder and the first screw 250 extends into the first housing 212; the second powder dispenser 310 includes a second powder hopper 311 and a second housing 312 that are interconnected, wherein the second powder hopper 311 is configured to store a second powder and the second screw 350 extends into the second housing 312.

[0034] Preferably, the powder suction assembly 400 includes a third movable plate 420, and a powder suction device 410 is connected to the third movable plate 420. One end of the powder suction device 410, which is provided with a powder suction port, passes through the third movable plate 420, and the other end of the powder suction device 410 is connected to an external powder suction device through a pipe.

[0035] It is worth mentioning that this powder suction device can be used for industrial powder recovery systems.

[0036] Preferably, the system further includes a drive assembly 500, which includes a rack 510 connected to the base plate 100, and a first drive motor 520, a second drive motor 530, and a third drive motor 540 respectively connected to the first moving plate 220, the second moving plate 320, and the third moving plate 420. The length direction of the rack 510 is parallel to the powder spreading direction or the powder suction direction. The output end of the first drive motor 520 is connected to a first gear 550 that meshes with the rack 510, the output end of the second drive motor 530 is connected to a second gear 560 that meshes with the rack 510, and the third drive motor 540... The output end is connected to a third gear 570 that meshes with the rack 510. The first drive motor 520 drives the first gear 550 to rotate, and through the meshing transmission between the first gear 550 and the rack 510, the first powder spreading component 200 moves horizontally. The second drive motor 530 drives the second gear 560 to rotate, and through the meshing transmission between the second gear 560 and the rack 510, the second powder spreading component 300 moves horizontally. The third drive motor 540 drives the third gear 570 to rotate, and through the meshing transmission between the third gear 570 and the rack 510, the powder suction component 400 moves horizontally.

[0037] It is worth mentioning that, since the powder suction component 400 operates synchronously with either the first powder spreading component 200 or the second powder spreading component 300, and during operation, the powder suction component 400 is always positioned in front of the powder spreading component along the direction of movement, a power drive structure is not required on the powder suction component 400; that is, the third drive motor 540 and the third gear 570 connected to the output end of the third drive motor 540 are not required. When the powder suction component 400 operates synchronously with the first powder spreading component 200, the first drive motor 520 can drive the first powder spreading component 200 and the powder suction component 400 to move synchronously through the meshing transmission between the first gear 550 and the rack 510. When the powder suction component 400 operates synchronously with the second powder spreading component 300, the second drive motor 530 can drive the second powder spreading component 300 and the powder suction component 400 to move synchronously through the meshing transmission between the second gear 560 and the rack 510. This reduces the overall production cost of the device.

[0038] It is further noted that the output end of the first drive motor 520 is connected to the first gear 550 through the first reducer, the output end of the second drive motor 530 is connected to the second gear 560 through the second reducer, and the output end of the third drive motor 540 is connected to the third gear 570 through the third reducer.

[0039] Preferably, the drive assembly 500 further includes two parallel slide rails 580 connected to the base plate 100, a first slider 590 connected to both ends of the first moving plate 220, a second slider 5100 connected to both ends of the second moving plate 320, and a third slider 5200 connected to both ends of the third moving plate 420, wherein the two first sliders 590, the two second sliders 5100, and the two third sliders 5200 are respectively slidably connected to the corresponding slide rails 580.

[0040] It is worth mentioning that the straightness of the movement of the first powder spreading component 200, the second powder spreading component 300, and the powder suction component 400 is ensured by the cooperation between the slider and the slide rail 580.

[0041] This invention also provides a powder spreading method for multi-material printing, comprising the following steps: S1: The first powder spreading component 200 moves horizontally from the first end 111 of the printing area 110 to the second end 112, forming a first powder layer in the printing area 110; S2: The laser performs laser printing within the first powder layer along a preset trajectory, forming a first powder printing layer and residual first powder; S3: The powder suction component 400 and the second powder spreading component 300 move synchronously from the first end 111 to the second end 112 of the printing area 110 in the horizontal direction, and the powder suction component 400 absorbs the first powder remaining in step S2; S4: The second powder spreading component 300 moves horizontally from the second end 112 of the printing area 110 to the first end 111, forming a second powder layer in the printing area 110; S5: The laser performs laser printing within the second powder layer along a preset trajectory, forming a second powder printing layer and residual second powder; S6: The powder suction component 400 and the first powder spreading component 200 move synchronously from the second end 112 to the first end 111 of the printing area 110 in the horizontal direction, and the powder suction component 400 absorbs the second powder remaining in step S5. S7: Repeat steps S1-S6 until the product printing is complete.

[0042] It is worth mentioning that during the first powder spreading, only the first powder spreading component 200 moves, so only the first powder is present in the printing area 110. After the laser performs laser printing along the preset trajectory, the only remaining powder in the printing area 110 is the first powder. Then, the powder suction component 400 and the second powder spreading component 300 operate synchronously. During the operation of the powder suction component 400 and the second powder spreading component 300, the powder suction component 400 is "in front" and the second powder spreading component 300 is "behind". In other words, the powder suction component 400 approaches the first end 111 of the printing area 110 first, and the powder spreading component approaches the printing area later. The first end 111 of 110 allows the powder suction component 400 to completely remove the residual first powder within the printing area 110. When the second powder spreading component 300 enters the printing area 110, even if powder leakage occurs, since there is no residual first powder in the printing area 110 at this time, the second powder leaking from the second powder spreading component 300 will not cause cross-contamination within the printing area 110. Furthermore, after the residual first powder is removed, the next step is for the second powder spreading component 300 to operate. Therefore, when the second powder spreading component 300 is in the printing area... When the second powder is spread evenly within area 110, the second powder falling from the second powder spreading component 300 mixes with the second powder leaking from the second powder spreading component 300 during the synchronous operation of the previous powder suction component 400 and the second powder spreading component 300. Since both are second powders, there is no cross-contamination. After laser printing along the preset trajectory, only the second powder remains. Then, the powder suction component 400 and the first powder spreading component 200 operate synchronously, with the powder suction component 400 "in front" and the first powder spreading component 200 "behind." The powder suction component 400 can pick up the powder from the printing area 110. All the remaining second powder in the printing area 110 will not cause cross-contamination when the first powder spreading component 200 enters the printing area 110, even if powder leakage occurs. Furthermore, after the remaining second powder is removed, the next step is for the first powder spreading component 200 to operate. Therefore, when the first powder spreading component 200 spreads the first powder in the printing area 110, the first powder falling from the first powder spreading component 200 mixes with the first powder leaking from the first powder spreading component 200 during the synchronous operation of the previous powder suction component 400 and the first powder spreading component 200. Since both are first powders, there is again no cross-contamination. This process is repeated, ensuring that there is no cross-contamination between the two powders at any step, thus guaranteeing the quality and performance of the formed product.

[0043] More preferably, step S1 includes the following steps: S11: Drive the first drive motor 520, and through the meshing transmission between the first gear 550 and the rack 510, cause the first moving plate 220 to move in the horizontal direction; S12: When the first moving plate 220 moves to a preset displacement of the first end 111 of the printing area 110, the first powder dispenser 210 is turned on, and the first powder in the printing area 110 is scraped flat under the action of the first scraper 240. S13: When the first moving plate 220 moves to a preset displacement at the second end 112 of the printing area 110, the first powder dispenser 210 is turned off. At this time, a first powder layer is formed in the printing area 110.

[0044] More preferably, for step S3, When the powder suction assembly 400 is not equipped with a power drive structure, the following steps are included: S31: Drive the second drive motor 530, and through the meshing transmission between the second gear 560 and the rack 510, cause the second moving plate 320 to move in the horizontal direction. When the second moving plate 320 contacts the third moving plate 420, the second moving plate 320 and the third moving plate 420 move in the horizontal direction synchronously, so as to realize that the powder suction component 400 and the second powder spreading component 300 move in the horizontal direction synchronously. S32: When the third moving plate 420 moves to a preset displacement of the first end 111 of the printing area 110, the powder suction device 410 is turned on to suck up the first powder remaining in step S2. Based on the function of the powder suction device 410, the second scraper 340 never comes into contact with the first powder when it moves. S33: When the third moving plate 420 moves to a preset displacement at the second end 112 of the printing area 110, the powder suction device 410 is turned off. At this time, there is no residual first powder in the printing area 110, but there may be second powder leaked by the synchronously moving second powder spreading component 300 when it passes through the printing area 110.

[0045] When the power drive structure is installed on the powder suction component 400, the following steps are included: S31: Drive the third drive motor 540, which drives the third moving plate 420 to move horizontally through the meshing transmission between the third gear 570 and the rack 510; at the same time, drive the second drive motor 530, which drives the second moving plate 320 to move horizontally through the meshing transmission between the second gear 560 and the rack 510, so as to realize that the powder suction component 400 and the second powder spreading component 300 move horizontally synchronously. S32: When the third moving plate 420 moves to a preset displacement of the first end 111 of the printing area 110, the powder suction device 410 is turned on to suck up the first powder remaining in step S2. Based on the function of the powder suction device 410, the second scraper 340 never comes into contact with the first powder when it moves. S33: When the third moving plate 420 moves to a preset displacement at the second end 112 of the printing area 110, the powder suction device 410 is turned off. At this time, there is no residual first powder in the printing area 110, but there may be second powder leaked by the synchronously moving second powder spreading component 300 when it passes through the printing area 110.

[0046] More preferably, step S4 includes the following steps: S41: Drive the second drive motor 530, and through the meshing transmission between the second gear 560 and the rack 510, cause the second moving plate 320 to move in the horizontal direction; S42: When the second moving plate 320 moves to a preset displacement at the second end 112 of the printing area 110, the second powder dispenser 310 is turned on, and the second powder in the printing area 110 is scraped flat by the second scraper 340. S43: When the second moving plate 320 moves to a preset displacement at the first end 111 of the printing area 110, the second powder dispenser 310 is turned off. At this time, a second powder layer is formed in the printing area 110.

[0047] More preferably, for step S6, When the powder suction assembly 400 is not equipped with a power drive structure, the following steps are included: S61: Drive the first drive motor 520, and through the meshing transmission between the first gear 550 and the rack 510, cause the first moving plate 220 to move in the horizontal direction. When the first moving plate 220 contacts the third moving plate 420, the first moving plate 220 and the third moving plate 420 move in the horizontal direction synchronously, so as to realize that the powder suction component 400 and the first powder spreading component 200 move in the horizontal direction synchronously. S62: When the third moving plate 420 moves to the second end 112 of the printing area 110 at a preset displacement, the powder suction device 410 is turned on to suck up the second powder remaining in step S5. Based on the function of the powder suction device 410, the first scraper 240 never comes into contact with the second powder when it moves. S63: When the third moving plate 420 moves to a preset displacement of the first end 111 of the printing area 110, the powder suction device 410 is turned off. At this time, there is no residual second powder in the printing area 110, but there may be first powder leaked by the synchronously moving first powder spreading component 200 when it passes through the printing area 110.

[0048] When the power drive structure is installed on the powder suction component 400, the following steps are included: S61: Drive the third drive motor 540, and through the meshing transmission between the third gear 570 and the rack 510, cause the third moving plate 420 to move in the horizontal direction; at the same time, drive the first drive motor 520, and through the meshing transmission between the first gear 550 and the rack 510, cause the first moving plate 220 to move in the horizontal direction, so as to realize that the powder suction component 400 and the first powder spreading component 200 move synchronously in the horizontal direction; S62: When the third moving plate 420 moves to the second end 112 of the printing area 110 at a preset displacement, the powder suction device 410 is turned on to suck up the second powder remaining in step S5. Based on the function of the powder suction device 410, the first scraper 240 never comes into contact with the second powder when it moves. S63: When the third moving plate 420 moves to a preset displacement of the first end 111 of the printing area 110, the powder suction device 410 is turned off. At this time, there is no residual second powder in the printing area 110, but there may be first powder leaked by the synchronously moving first powder spreading component 200 when it passes through the printing area 110.

[0049] In this embodiment, the reasonable layout of the first powder spreading component 200, the second powder spreading component 300, and the powder suction component 400, along with the control logic for powder spreading and suction, avoids the impact of powder leakage on the powder layer. In addition, by using two scrapers to level different powders, cross-contamination of heterogeneous powders due to powder residue on the scrapers is avoided. At the same time, under the action of the powder suction device 410, the non-powder spreading scrapers in the powder spreading component that move synchronously with it will not come into contact with the powder, further avoiding cross-contamination of powders and ensuring the quality and performance of the product after molding.

[0050] It should be noted that in this invention, the use of terms such as "first," "second," and "a" is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified. The terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two elements or the interaction between two elements, unless otherwise explicitly specified. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0051] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0052] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A powder spreading method for multi-material printing, characterized by, Including the following steps: S1: The first powder spreading component moves horizontally from the first end to the second end of the printing area to form a first powder layer in the printing area; S2: The laser performs laser printing within the first powder layer along a preset trajectory, forming a first powder printing layer and residual first powder; S3: The powder suction component and the second powder spreading component move synchronously from the first end to the second end of the printing area in the horizontal direction, and the powder suction component absorbs the residual first powder in step S2. S4: The second powder spreading component moves horizontally from the second end to the first end of the printing area to form a second powder layer in the printing area; S5: The laser performs laser printing within the second powder layer along a preset trajectory, forming a second powder printing layer and residual second powder; S6: The powder suction component and the first powder spreading component move synchronously from the second end to the first end of the printing area in the horizontal direction, and the powder suction component absorbs the second powder remaining in step S5. S7: Repeat steps S1-S6 until the product printing is complete.

2. The powder spreading method for multi-material printing according to claim 1, wherein, Regarding step S3, When the powder suction assembly is not equipped with a power drive structure, step S3 includes the following steps: S31: Drive the second drive motor, and through the meshing transmission between the second gear and the rack, cause the second moving plate to move in the horizontal direction. When the second moving plate comes into contact with the third moving plate, the second moving plate and the third moving plate move in the horizontal direction synchronously, so as to realize that the powder suction component and the second powder spreading component move in the horizontal direction synchronously. S32: When the third moving plate moves to a preset displacement at the first end of the printing area, the powder suction device is turned on to suck up the first powder remaining in step S2. Based on the function of the powder suction device, the second scraper never comes into contact with the first powder when it moves. S33: When the third moving plate moves to the second preset displacement from the printing area, the powder suction device is turned off, and at this time there is no residual first powder in the printing area; When the power drive structure is installed on the powder suction component, step S3 includes the following steps: S31: Drives the third drive motor, which, through the meshing transmission between the third gear and the rack, causes the third moving plate to move horizontally; at the same time, drives the second drive motor, which, through the meshing transmission between the second gear and the rack, causes the second moving plate to move horizontally, so that the powder suction component and the second powder spreading component move horizontally synchronously. S32: When the third moving plate moves to a preset displacement at the first end of the printing area, the powder suction device is turned on to suck up the first powder remaining in step S2. Based on the function of the powder suction device, the second scraper never comes into contact with the first powder when it moves. S33: When the third moving plate moves to the second preset displacement distance from the printing area, the powder suction device is turned off, and at this time there is no residual first powder in the printing area.

3. The powder spreading method for multi-material printing of claim 1, wherein, Regarding step S6, When the powder suction assembly is not equipped with a power drive structure, step S6 includes the following steps: S61: Drive the first drive motor, and through the meshing transmission between the first gear and the rack, cause the first moving plate to move in the horizontal direction. When the first moving plate comes into contact with the third moving plate, the first moving plate and the third moving plate move in the horizontal direction synchronously, so as to realize that the powder suction component and the first powder spreading component move in the horizontal direction synchronously. S62: When the third moving plate moves to the second end of the printing area at a preset displacement, the powder suction device is turned on to suck up the second powder remaining in step S5. Based on the function of the powder suction device, the first scraper never comes into contact with the second powder when it moves. S63: When the third moving plate moves to a preset displacement at the first end of the printing area, the powder suction device is turned off, and at this time there is no residual second powder in the printing area; When the power drive structure is installed on the powder suction component, step S6 includes the following steps: S61: Drive the third drive motor to move the third moving plate horizontally through the meshing transmission between the third gear and the rack; at the same time drive the first drive motor to move the first moving plate horizontally through the meshing transmission between the first gear and the rack, so as to realize that the powder suction component and the first powder spreading component move horizontally synchronously. S62: When the third moving plate moves to the second end of the printing area at a preset displacement, the powder suction device is turned on to suck up the second powder remaining in step S5. Based on the function of the powder suction device, the first scraper never comes into contact with the second powder when it moves. S63: When the third moving plate moves to a preset displacement at the first end of the printing area, the powder suction device is turned off, and at this time there is no residual second powder in the printing area.

4. A powder spreading device for multi-material printing, based on the powder spreading method for multi-material printing according to any one of claims 1 to 3, characterized in that include: A base plate having a printing area configured for powder laser printing, the printing area including a first end and a second end; A first powder spreading component, a second powder spreading component, and a powder suction component are slidably connected to the base plate. The first powder spreading component includes a first powder dropper, the second powder spreading component includes a second powder dropper, and the powder suction component includes a powder suction component. The planes where the powder dropper, the powder dropper, and the powder suction component are located are all higher than the plane of the printing area. During powder spreading, the first and second powder spreading components operate alternately and independently. During powder suction, the powder suction component operates alternately and synchronously with the first and second powder spreading components.

5. The powder spreading device for multi-material printing according to claim 4, characterized in that, It includes a first movable plate, a second movable plate and a third movable plate, wherein the first movable plate is provided with the first powder dispenser and the first scraper, the second movable plate is provided with the second powder dispenser and the second scraper, and the third movable plate is provided with the powder suction device, wherein the first scraper and the second scraper are arranged opposite to each other and are correspondingly connected to the side of the first movable plate and the second movable plate facing the third movable plate.

6. The powder spreading apparatus for multi-material printing according to claim 5, characterized in that, When the powder suction device and the second powder discharge device move synchronously, there is a gap in the vertical direction between the plane where the lowest edge of the second scraper on the second moving plate is located and the residual first powder in the printing area; when the powder suction device and the first powder discharge device move synchronously, there is a gap in the vertical direction between the plane where the lowest edge of the first scraper on the first moving plate is located and the residual second powder in the printing area.

7. The powder spreading device for multi-material printing according to claim 4, characterized in that, When the toner suction device and the second toner discharge device move synchronously, the toner suction device enters the printing area before the second toner discharge device; when the toner suction device and the first toner discharge device move synchronously, the toner suction device enters the printing area before the first toner discharge device.

8. The powder spreading device for multi-material printing according to claim 5, characterized in that, Also includes: The rack is connected to the base plate, and the length direction of the rack is parallel to the powder spreading direction or the powder absorption direction; A first drive motor is mounted on a first movable plate, and the output end of the first drive motor is connected to a first gear that meshes with a rack. The second drive motor is mounted on the second movable plate, and the output end of the second drive motor is connected to a second gear that meshes with the rack.

9. The powder spreading device for multi-material printing according to claim 8, characterized in that, Also includes: The third drive motor is mounted on the third movable plate, and the output end of the third drive motor is connected to a third gear that meshes with the rack.

10. The powder spreading apparatus for multi-material printing according to claim 5, characterized in that, It also includes two parallel slide rails connected to the base plate, a first slider connected to both ends of the first movable plate, a second slider connected to both ends of the second movable plate, and a third slider connected to both ends of the third movable plate, wherein the two first sliders, the two second sliders, and the two third sliders are respectively slidably connected to the corresponding slide rails.

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