Powder supply device for additive manufacturing multi-mode powder
By designing the roller assembly and mixing components of the powder feeding device, the problem of uneven mixing of multimodal powders was solved, achieving uniform powder bed placement and high density, thus improving the product quality of additive manufacturing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-13
- Publication Date
- 2026-03-13
AI Technical Summary
In additive manufacturing, the uneven mixing of multimodal powders due to differences in particle size and density leads to inconsistent powder bed density, which affects product quality.
Design a powder supply device comprising multiple powder feeding mechanisms, a powder mixing component, a drive component, and a mixing component. Through the rotation of the roller assembly and the stirring of the mixing component, uniform mixing of multimodal powders is achieved, and the mixing effect is enhanced by tooth-like protrusions and a vibrator.
This method achieves uniform mixing of multimodal powders, improves the density consistency and mixing quality of the powder bed, and reduces dimensional differences and deformation defects in the green body during sintering.
Smart Images
Figure CN223989076U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of plunger pump parts processing technology, and in particular to a powder supply device for additive manufacturing of multimodal powders. Background Technology
[0002] Currently, in the powder metallurgy industry, multimodal powder mixing is commonly used to improve the density of green bodies. This method has been extended to the additive manufacturing industry. According to the powder proportioning theory proposed by Ayer and Soppe, the maximum density achievable by a dual-modal powder system is when the two modal powders have different particle size ratios D1 / D2, at which point the particle size ratio D1 / D2 > 6. Especially for binder spraying additive manufacturing, directly mixing multimodal powders in practice will inevitably lead to segregation due to particle size inhomogeneity. This prevents the powder bed from being laid out according to the preset powder ratio, and also compromises the uniformity of density among the green bodies formed, and even the internal uniformity of density within the same green body. Green bodies in this state are prone to batch-to-batch dimensional differences or sintering performance variations during subsequent debinding and sintering processes, and may even result in sintering deformation defects. Therefore, in binder spraying molding processes, the uniformity and consistency of the powder bed play a crucial role in controlling the shape and properties of the product.
[0003] In the field of multi-material additive manufacturing, there are differences in the theoretical density between different materials. Even if powders with the same particle size range are used in additive manufacturing, they cannot be mixed evenly during the mixing process, which can easily lead to segregation in practical applications.
[0004] Therefore, there is an urgent need for a powder feeding device for additive manufacturing of multimodal powders to solve the problem of uneven mixing due to segregation caused by differences in particle size or density of multimodal powders, and to achieve high-density powder bed placement. Utility Model Content
[0005] The purpose of this invention is to provide a powder supply device for additive manufacturing of multimodal powders, which solves the problems existing in the prior art. It has a simple structure, is easy to use, and effectively ensures the uniform mixing of multimodal powders.
[0006] To achieve the above objectives, this utility model provides the following solution:
[0007] This utility model provides a powder feeding device for additive manufacturing multimodal powders, comprising: multiple powder feeding mechanisms, a powder mixing assembly, a driving component, and a mixing component. The multiple powder feeding mechanisms are used to respectively place powders of different modes. The powder mixing assembly includes a fixed support and a roller assembly. The roller assembly is horizontally arranged and rotatably connected to the fixed support. The first end of the roller assembly is used to communicate with the feed port of the multiple powder feeding mechanisms to receive the powders conveyed by the multiple powder feeding mechanisms and form multimodal mixed powders. The fixed end of the driving component is fixedly connected to the fixed support, and its driving end is drivenly connected to the roller assembly through a transmission assembly to drive the roller assembly to rotate. The mixing component is placed inside the roller assembly to mix the multimodal mixed powders evenly during the rotation of the roller assembly.
[0008] Preferably, the mixing component comprises a plurality of spheres and / or a plurality of cylindrical rods.
[0009] Preferably, the roller assembly includes a cylinder, a first end cap, a second end cap, and a baffle. The cylinder is arranged horizontally. The first end cap is fastened to the first end of the cylinder, and the feeding ports of the plurality of powder-discharging mechanisms are connected to the first end cap and communicate with the inner cavity of the cylinder. The second end cap is fastened to the second end of the cylinder, and the output end of the transmission assembly is drivenly connected to the second end cap. Powder-discharging holes are formed on the inner sidewall of the cylinder along its axial direction, and the baffle is disposed on the outer side of the cylinder to open or close the powder-discharging holes.
[0010] Preferably, it further includes a first vibrator, which is disposed on the outside of the second end cap; the inner wall of the cylinder is provided with tooth-like protrusions for enhancing the uniformity of mixing.
[0011] Preferably, the roller assembly further includes a first bearing, a second bearing, a first shaft tube, and a second shaft tube. The fixed bracket is provided with a first fixed station and a second fixed station. The first bearing and the second bearing are respectively fixed at the first fixed station and the second fixed station. The first shaft tube passes through the inner ring of the first bearing and is interference-fitted with the first bearing. The second shaft tube passes through the inner ring of the second bearing and is interference-fitted with the second bearing. The first shaft tube and the second shaft tube are arranged on the same axis.
[0012] One end of the first shaft tube is connected to and communicates with the output port of each of the total powder dropping mechanisms, and the other end is connected to and communicates with the inner cavity of the cylinder; one end of the second shaft tube is drivenly connected to the second end cap and communicates with the inner cavity of the cylinder; the output end of the transmission assembly is drivenly connected to the second shaft tube.
[0013] Preferably, the driving component is a micro motor, the transmission assembly includes a belt and a transmission wheel, a third fixed station is provided on the fixed bracket, and the micro motor is fixed to the third fixed station; the transmission wheel is sleeved on the outside of the second shaft tube and fixedly connected to the second shaft tube, and the belt drive connects the output shaft of the micro motor and the transmission wheel to drive the second shaft tube to rotate the cylinder.
[0014] Preferably, it further includes a main conveying pipe, a first sealing pipe joint, a gas output pipe, and a second sealing pipe joint. The first sealing pipe joint and the second sealing pipe joint are both two-section pipe structures capable of sealing and rotating connection. One end of the main conveying pipe is used to connect and communicate with the output port of each of the main powder dropping mechanisms. The end of the first sealing pipe joint away from the main powder dropping mechanism is used to connect and communicate with the first shaft pipe to achieve a sealed rotating connection between the main conveying pipe and the first shaft pipe. One end of the second sealing pipe joint is used to connect and communicate with the second shaft pipe, and the other end is used to connect and communicate with the gas output pipe to achieve a rotating connection between the second shaft pipe and the gas output pipe.
[0015] Preferably, the main powder feeding mechanism includes a hopper, a powder feeding pipe, and a powder feeding protective gas conveying pipe. The hopper is arranged above one side of the first end cover. The upper end of the powder feeding pipe is connected to and communicates with the bottom of the hopper, and the lower end is connected to and communicates with the main conveying pipe. The outlet end of the powder feeding protective gas conveying pipe is connected to the powder feeding pipe to convey protective gas to the powder feeding pipe to drive the powder into the cylinder. The other end of the main conveying pipe is connected to and communicates with the first shaft pipe.
[0016] Preferably, a filter screen is provided inside the second end cap, the mesh size of the filter screen is smaller than the minimum powder particle size in the multimodal mixed powder, and the end of the gas output pipe away from the second shaft tube is connected to the air inlet of the powder delivery protective gas conveying pipe through an exhaust pipe.
[0017] Preferably, the total powder discharge mechanism further includes a second vibrator, a valve body, and a precision balance. The second vibrator is disposed at the bottom of the hopper, the valve body is disposed at one end of the powder feeding pipe near the hopper, and the precision balance is disposed on the powder feeding pipe between the valve body and the powder feeding protective gas conveying pipe.
[0018] The present invention achieves the following technical advantages over the prior art:
[0019] 1. This utility model provides a powder supply device for additive manufacturing of multimodal powders. By setting multiple main powder feeding mechanisms, different main powder feeding mechanisms can respectively place powders of different modalities. This allows for precise control of the proportion and supply amount of different modal powders according to actual needs. The roller assembly, as a mixing container, rotates under the drive of the drive component. The rotation of the roller assembly causes the powder to continuously tumble and flow inside, increasing the opportunities for collision and interaction between powders and improving the uniformity of mixing. Compared with static mixing methods, dynamic stirring and rotation can more effectively break up powder agglomeration and stratification, achieving better mixing results. In addition, the mixing component is placed inside the roller assembly. As the roller assembly rotates, the mixing component can fully stir and mix the multimodal powders. This mechanical stirring method allows powders of different modalities to fully contact and mix within the roller assembly, ensuring that the mixed powder has uniform composition and properties.
[0020] 2. Furthermore, tooth-like protrusions are provided on the inner wall of the cylinder, which increases the friction between the powder and the cylinder, further improving the mixing effect. Attached Figure Description
[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0022] Figure 1 A schematic diagram of the powder supply device for additive manufacturing of multimodal powders provided by this utility model;
[0023] In the diagram: 1. Fixed bracket; 2. First shaft tube; 3. First end cap; 4. Roller assembly; 5. Second end cap; 6. First vibrator; 7. Third fixed station; 8. Micro motor; 9. Belt; 10. Second bearing; 11. Gas output pipe; 12. Exhaust pipe; 13. Second sealing pipe joint; 14. Transmission wheel; 15. Second fixed station; 16. Powder discharge hole; 17. Cylindrical rod; 18. Multimodal mixed powder; 19. Sphere; 20. Inner wall of cylinder; 21. First fixed station; 22. First bearing; 23. First sealing pipe joint; 24. Powder feeding pipe; 25. Powder feeding protective gas conveying pipe; 26. Precision balance; 27. Valve body; 28. Hopper; 29. Second vibrator; 30. Main powder discharge mechanism; 31. Conveying main pipe. Detailed Implementation
[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0025] The purpose of this invention is to provide a powder supply device for additive manufacturing of multimodal powders, which solves the problems existing in the prior art. It has a simple structure, is easy to use, and effectively ensures the uniform mixing of multimodal powders.
[0026] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0027] This utility model provides a powder supply device for additive manufacturing of multimodal powders, such as... Figure 1 As shown, the system includes: multiple powder feeding mechanisms 30, a fixed support 1, a roller assembly 4, a drive unit, and a mixing unit. Each powder feeding mechanism 30 is used to place powders of different modalities. The first and second ends of the roller assembly 4 are rotatably connected to the fixed support 1. The first end of the roller assembly 4 is connected and communicates with each powder feeding mechanism 30 to receive the powder conveyed by each powder feeding mechanism 30 and form a multimodal mixed powder 18. One end of the drive unit is fixedly connected to the fixed support 1, and the other end is connected to the roller assembly 4 to drive the roller assembly 4 to rotate. The mixing unit is placed inside the roller assembly 4 to mix the multimodal mixed powder 18 evenly during the rotation of the roller assembly 4. By setting multiple powder feeding mechanisms 30, powders of different modalities can be placed separately, thus enabling precise control of the proportion and supply of different modal powders according to actual needs. The roller assembly 4, as a mixing container, rotates under the drive of the drive unit. The rotation of the roller assembly 4 causes the powder to continuously tumble and flow inside, increasing the opportunities for collision and interaction between powders and improving the uniformity of mixing. Compared to static mixing, dynamic stirring and rotation can more effectively break up powder agglomeration and stratification, achieving better mixing results. Furthermore, the mixing component is placed inside the drum assembly 4. As the drum assembly 4 rotates, the mixing component can fully stir and mix the multimodal mixed powder 18. This mechanical stirring method allows powders of different modes to fully contact and mix inside the drum assembly 4, ensuring that the mixed powder has uniform composition and properties.
[0028] In a preferred embodiment, the mixing component includes a plurality of spheres 19. Preferably, the diameter of the spheres 19 is 3mm to 5mm. The spheres 19 with a diameter of 3mm to 5mm can better contact the powder when the roller assembly 4 rotates, further enhancing the mixing effect on the multimodal mixed powder 18 and improving the mixing uniformity.
[0029] In a preferred embodiment, the mixing component further includes a plurality of cylindrical rods 17. Preferably, the length of the cylindrical rods 17 is 1 / 3 to 1 / 2 of the axial length of the roller assembly 4. The cylindrical rods 17 with a length of 1 / 3 to 1 / 2 of the length of the roller assembly 4 can stir the powder at different positions and cooperate with the spheres 19 to improve the mixing effect of the powder in all directions.
[0030] In a preferred embodiment, the roller assembly 4 includes a first end cap 3, a cylinder, a baffle, and a second end cap 5. The first end cap 3 is detachably fixedly connected to the first end of the cylinder. Specifically, the first end cap 3 is threadedly connected to the first end of the cylinder. The second end cap 5 is detachably fixedly connected to the second end of the cylinder. Specifically, the second end cap 5 is threadedly connected to the second end of the cylinder. A powder discharge hole 16 is provided on the side wall of the cylinder. The baffle is provided outside the powder discharge hole 16 to open or close the powder discharge hole 16. The opening and closing action of the baffle at the powder discharge hole 16 can be realized by a pneumatic device. Preferably, the cylinder is made of ceramic or tungsten alloy.
[0031] In a preferred embodiment, the powder feeding device for additive manufacturing of multimodal powder further includes a first vibrator 6, which is disposed on the outside of the second end cap 5. Preferably, the first vibrator 6 is an ultrasonic vibrator, and the inner wall of the cylinder is provided with tooth-like protrusions. During the rotation of the roller assembly 4, the vibration of the first ultrasonic vibrator can make the powder move more actively within the roller assembly 4, enhancing the mixing effect of the cylindrical rod 17 and the sphere on the powder. Through vibration, the powder can better contact the cylindrical rod 17 and the sphere, thereby improving the mixing uniformity of the powder, ensuring that the multimodal powder can be mixed according to the preset ratio, and improving the density consistency of the preform. The tooth-like protrusions on the inner wall 20 of the cylinder increase the friction between the powder and the cylinder, further improving the mixing effect.
[0032] In a preferred embodiment, the powder supply device for additive manufacturing of multimodal powders further includes a first shaft tube 2, a first bearing 22, a second shaft tube, and a second bearing 10. Both the first and second shaft tubes are hollow tubular structures. One end of the first shaft tube 2 is connected to and communicates with the output port of each main powder feeding mechanism 30. The second shaft tube is connected to and communicates with the second end cap 5. A first fixed station 21 and a second fixed station 15 are provided on the fixed bracket 1. The first bearing 22 and the second bearing 10 are respectively fixedly connected to the first fixed station 21 and the second fixed station 15. The first shaft tube 2 passes through the inner ring of the first bearing 22 and is interference-fitted with the first bearing 22. The second shaft tube passes through the inner ring of the second bearing 10 and is interference-fitted with the second bearing 10. The first and second shaft tubes are coaxially arranged. The hollow tubular structure of the first and second shaft tubes facilitates powder transport. The bearing arrangement ensures stable rotation of the connecting shaft, improving the operational reliability of the device. The coaxial arrangement ensures smooth rotation of the roller assembly 4, improving the mixing effect.
[0033] In a preferred embodiment, the driving component includes a micro motor 8, a belt 9, and a transmission wheel 14. A third fixed station 7 is provided on the fixed bracket 1. The micro motor 8 is fixedly connected to the third fixed station 7. The transmission wheel 14 is sleeved on the outside of the second shaft tube and fixedly connected to the second shaft tube. The belt 9 is used to connect the output shaft of the micro motor 8 and the transmission wheel 14 to drive the transmission wheel 14 to rotate. The micro motor 8 drives the roller assembly 4 to rotate through the belt 9 and the transmission wheel 14. The transmission is smooth and the rotation speed of the roller assembly 4 can be precisely controlled to meet different mixing requirements.
[0034] In a preferred embodiment, the powder supply device for additive manufacturing multimodal powder further includes a main conveying pipe 31, a first sealing pipe joint 23, a gas output pipe 11, and a second sealing pipe joint 13. Both the first sealing pipe joint 23 and the second sealing pipe joint 13 are two-section pipe structures that can be sealed and rotatably connected. In the connected state, one section can be fixed and the other section can rotate around the axis. One end of the main conveying pipe 31 is used to connect and communicate with the output port of each main powder dropping mechanism 30. The end of the first sealing pipe joint 23 away from the main powder dropping mechanism 30 is used to connect and communicate with the first shaft pipe 2 to achieve a sealed rotatable connection between the main conveying pipe 31 and the first shaft pipe 2. One end of the second sealing pipe joint 13 is used to connect and communicate with the second shaft pipe, and the other end is used to connect and communicate with the gas output pipe 11 to achieve a rotatable connection between the second shaft pipe and the gas output pipe 11. The sealed rotatable connection of the joint ensures the sealing during the powder conveying process, while allowing the connecting shaft to rotate. It can directly rotate the sleeve after the powder is conveyed, ensuring the continuity of the device and improving the flexibility and reliability of the device.
[0035] In a preferred embodiment, the main powder feeding mechanism 30 includes a hopper 28, a powder feeding pipe 24, and a powder feeding protective gas conveying pipe 25. One end of the powder feeding pipe 24 is connected to and communicates with the bottom of the hopper 28, and the other end is connected to and communicates with the main conveying pipe 31. One end of the powder feeding protective gas conveying pipe 25 is connected to and communicates with the powder feeding pipe 24 and can convey protective gas to the powder feeding pipe 24 to drive the powder into the cylinder. A filter screen is provided inside the second end cover 5. The mesh size of the filter screen is smaller than the minimum powder particle size in the multimodal mixed powder 18, and the gas output... The end of pipe 11 furthest from the second shaft pipe is connected to the inlet end of the powder feeding protective gas conveying pipe 25 via an exhaust pipe 12. The exhaust pipe 12 is connected to the second shaft pipe via a quick connector. Preferably, the exhaust pipe 12 is φ6~8mm. The hopper 28 is configured as a "V-shaped barrel" structure. The powder feeding protective gas conveying pipe 25 includes an "L-shaped" hollow pipe that partially extends into the powder feeding pipe 24. Preferably, the protective gas can be argon or nitrogen. The protective gas is ultimately discharged from the exhaust pipe 12 and can be recycled and re-enter the powder feeding protective gas conveying pipe 25. The "V-shaped barrel" hopper 28 facilitates powder flow. The powder feeding protective gas conveying pipe 25 uses protective gas to transport powder, improving powder flowability and conveying efficiency. A filter screen prevents powder from flowing out of the roller assembly 4. The exhaust pipe 12 is φ6-8mm to ensure smooth gas discharge and recycling, saving resources.
[0036] In a preferred embodiment, the total powder feeding mechanism 30 further includes a second vibrator 29, a valve body 27, and a precision balance 26. The second vibrator 29 is disposed at the bottom of the hopper 28. Preferably, the second vibrator 29 is an ultrasonic vibrator. The valve body 27 is disposed at one end of the powder feeding pipe 24 near the hopper 28. The precision balance 26 is disposed on the powder feeding pipe 24 between the valve body 27 and the powder feeding protective gas conveying pipe 25. Preferably, the graduation value of the precision balance 26 is better than 0.001g. The ultrasonic vibrator at the bottom promotes the powder to enter the powder feeding pipe 24 from the hopper 28. The valve body 27 can control the amount of powder fed. The precision balance 26 has a graduation value better than 0.001g, which can accurately control the proportion of powders of different modes and improve the mixing quality.
[0037] In a preferred embodiment, the fixing bracket 1 is made of aluminum alloy. The aluminum alloy fixing bracket 1 has a light weight and good strength, which makes it easy to install and use, while ensuring the stability of the device.
[0038] The specific implementation process of the powder supply device for additive manufacturing multimodal powder provided by this utility model;
[0039] This invention determines the required particle size of the metal powder based on calculations. Assuming the particle sizes of the powder to be laid in the powder bed are D50=a and D50=b, and the mass ratio of the mixed powders is 1:3, it can be seen from the above that a total of 30 powder-feeding mechanisms 30 are required to lay the powder bed. The implementation process is as follows:
[0040] Powders of particle sizes a and b are placed in two main powder feeding mechanisms 30, with a single layer thickness of 0.03 mm. Assuming the forming area of the equipment is S and the powder bed density is ρ, the required powder for a single layer is 0.03 * S * (1.2~1.3)ρ. Therefore, the calculated powder requirements for a single layer are 1 / 4 * 0.03 * S * (1.2~1.3) for particle size a and 3 / 4 * 0.03 * S * (1.2~1.3) for particle size b. Due to the small particle size and insufficient flowability, the powder can be further processed by the second vibrator 29. Vibration causes the powder to fall into the precision balance 26. At the same time, the precision balance 26 weighs the corresponding powder and sends it into the roller assembly 4 under the action of protective gas through the powder delivery protective gas conveying pipe 25. The protective gas is filtered through the filter screen of the second end cover 5 and then returned to the powder delivery protective gas conveying pipe 25. The multimodal mixed powder 18 in the roller assembly 4 is mixed evenly under the action of the cylindrical rod 17 and the ball 19. After being mixed evenly, the powder falls through the powder falling hole 16 and finally, with the cooperation of the powder spreading roller, a high-quality powder bed is laid.
[0041] This utility model uses specific examples to illustrate its principles and implementation methods. The above description of the embodiments is only for the purpose of helping to understand the method and core idea of this utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the idea of this utility model. In summary, the content of this specification should not be construed as a limitation of this utility model.
Claims
1. A powder feed device for additive manufacturing of multimodal powders, characterized by: The application relates to a multi-modal powder mixing device, which comprises the following parts: a plurality of total powder falling mechanisms (30) for placing different modalities of powder respectively; a powder mixing assembly, which comprises a fixed support (1) and a roller assembly (4) horizontally arranged and rotationally connected with the fixed support (1), a first end of the roller assembly (4) being used for communicating with feeding ports of the plurality of total powder falling mechanisms (30) to receive powder delivered by the plurality of total powder falling mechanisms (30) and form multi-modal mixed powder (18); a driving member, a fixed end of the driving member being fixedly connected with the fixed support (1), and a driving end of the driving member being transmissionally connected with the roller assembly (4) through a transmission assembly to drive the roller assembly (4) to rotate; a stirring member arranged in the roller assembly (4) to uniformly mix the multi-modal mixed powder (18) during rotation of the roller assembly (4).
2. The powder feed device for additively manufacturing a multimodal powder of claim 1, characterized by: The stirring member comprises a plurality of spheres (19) and / or a plurality of cylindrical rods (17).
3. The powder feed apparatus for additively manufacturing a multimodal powder of claim 1, wherein: The roller assembly (4) comprises a barrel, a first end cover (3), a second end cover (5) and a baffle, the barrel being horizontally arranged; the first end cover (3) is fixedly connected with a first end of the barrel, the feeding ports of the plurality of total powder falling mechanisms (30) are connected with the first end cover and communicate with an inner cavity of the barrel; the second end cover (5) is fixedly connected with a second end of the barrel, an output end of the transmission assembly is transmissionally connected with the second end cover (5); a plurality of powder falling holes (16) are formed on an inner side wall of the barrel along an axial direction of the barrel, and the baffle is arranged on an outer side of the barrel to open or close the powder falling holes (16).
4. The powder supply device for additively manufacturing a multimodal powder according to claim 3, characterized in that: A first vibrator (6) is further arranged on an outer side of the second end cover (5); and the inner wall of the barrel is provided with tooth-shaped protrusions for enhancing mixing uniformity.
5. The powder feed apparatus for additively manufacturing a multimodal powder of claim 3, wherein: The roller assembly (4) further comprises a first bearing (22), a second bearing (10), a first shaft tube (2) and a second shaft tube, the fixed support (1) is provided with a first fixing station (21) and a second fixing station (15), the first bearing (22) and the second bearing (10) are fixedly arranged in the first fixing station (21) and the second fixing station (15) respectively, the first shaft tube (2) is connected with the first bearing (22) in an interference fit mode by penetrating through an inner ring of the first bearing (22), the second shaft tube is connected with the second bearing (10) in an interference fit mode by penetrating through an inner ring of the second bearing (10), and the first shaft tube (2) and the second shaft tube are coaxially arranged; one end of the first shaft tube (2) is connected with and communicates with output ports of the total powder falling mechanisms (30), the other end of the first shaft tube (2) is connected with and communicates with the inner cavity of the barrel, one end of the second shaft tube is transmissionally connected with and communicates with the inner cavity of the barrel, and an output end of the transmission assembly is transmissionally connected with the second shaft tube.
6. The powder supply device for additively manufacturing a multimodal powder according to claim 5, characterized in that: The driving member is a micro motor (8), the transmission assembly includes a belt (9) and a transmission wheel (14), a third fixed station (7) is arranged on the fixed support (1), and the micro motor (8) is fixed to the third fixed station (7); the transmission wheel (14) is sleeved outside the second shaft pipe and is fixedly connected with the second shaft pipe, and the belt (9) is in transmission connection with the output shaft of the micro motor (8) and the transmission wheel (14) to drive the second shaft pipe to drive the cylinder to rotate.
7. The powder supply device for additively manufacturing a multimodal powder according to claim 6, characterized in that: Further comprising a delivery main pipe (31), a first sealing pipe joint (23), a second sealing pipe joint (13) and a gas output pipe (11), one end of the delivery main pipe (31) is used for being connected with and communicating with the output port of each total powder falling mechanism (30), the first sealing pipe joint (23) is sealingly and rotatably connected and communicates the first shaft pipe (2) with the delivery main pipe (31); the second sealing pipe joint (13) is sealingly and rotatably connected and communicates the gas output pipe (11) with the second shaft pipe.
8. The powder supply device for additively manufacturing a multimodal powder according to claim 7, characterized in that: The total powder falling mechanism (30) comprises a hopper (28), a powder feeding pipe (24) and a powder feeding protective gas delivery pipe (25), the hopper (28) is arranged above the side of the first end cover; the upper end of the powder feeding pipe (24) is connected with and communicates with the bottom of the hopper (28), and the lower end is connected with and communicates with the delivery main pipe (31); the gas outlet end of the powder feeding protective gas delivery pipe (25) communicates with the powder feeding pipe (24) to deliver protective gas to the powder feeding pipe (24) to drive the powder into the cylinder.
9. The powder supply device for additively manufacturing a multimodal powder according to claim 8, characterized in that: The second end cover (5) is provided with a filter screen, the mesh aperture of the filter screen is smaller than the minimum powder particle size in the multimodal mixed powder (18), and the end, away from the second shaft pipe, of the gas output pipe (11) communicates with the gas inlet end of the powder feeding protective gas delivery pipe (25) through an exhaust pipe (12).
10. The powder supply device for additively manufacturing a multimodal powder according to claim 9, characterized in that: The total powder falling mechanism (30) further comprises a second vibrator (29), a valve body (27) and a precision balance (26), the second vibrator (29) is arranged at the bottom of the hopper (28), the valve body (27) is arranged at one end of the powder feeding pipe (24) close to the hopper (28), and the precision balance (26) is arranged on the powder feeding pipe (24) between the valve body (27) and the powder feeding protective gas delivery pipe (25).