Powder stirring and conveying mechanism, and additive manufacturing device

Abstract

The present application discloses a powder stirring and conveying mechanism, and an additive manufacturing device. The powder stirring and conveying mechanism comprises: a stirring cavity; a stirrer, which is at least partially located in the stirring cavity, and can be driven to rotate in a forward direction and a reverse direction, the stirrer comprising a main shaft and multiple stirring blades fixed on the main shaft; a powder supply plate, which is rotatably disposed in the stirring cavity, and comprises a main body capable of supporting powder and multiple mounting arms extending from the main body, the multiple mounting arms being rotatably disposed on the main shaft. The stirrer is configured to be able to contact the powder supply plate from one side of the powder supply plate and push the powder supply plate to rotate in the forward direction within the stirring cavity when rotating in the forward direction, and to be able to contact the powder supply plate from the other side of the powder supply plate and push the powder supply plate to rotate in the reverse direction within the stirring cavity when rotating in the reverse direction. The present solution, by means of separately providing a stirrer and a powder supply plate, not only facilitates daily maintenance of the mechanism, but also allows the stirrer to be designed with a relatively large swinging range as needed.

Description

Powder mixing and conveying mechanism and additive manufacturing equipment Technical Field

[0001] The present application relates to the technical field of additive manufacturing equipment, and in particular to a powder stirring and conveying mechanism for supplying powder material to a forming platform of an additive manufacturing equipment. Background Art

[0002] Additive manufacturing technology is a manufacturing method that is completely opposite to traditional material "removal" processing methods. It directly manufactures a three-dimensional physical entity model that is completely consistent with the corresponding mathematical model by adding material, based on three-dimensional CAD model data and usually adopting a layer-by-layer manufacturing method.

[0003] In additive manufacturing technology that uses powder as a building material, powdered material is continuously supplied to a forming platform, and the particles of the powdered material are layered and fused together to produce a three-dimensional object on a layer-by-layer basis.

[0004] Patent document publication number CN104837607A discloses a powder feeding mechanism for a three-dimensional printer, which includes a carrier arm that moves through a powder chamber and a support platform for carrying a pile of powdered building material; the support platform moves with the carrier arm, and the carrier arm moves to a powder delivery position in which the support platform is in a lateral orientation so as to be flush with the material bed.

[0005] Patent document No. CN112041152A discloses an apparatus for supplying material to an additive manufacturing platform, comprising a rotatable delivery module including a blade and a plurality of distribution elements. In use, the rotatable delivery module is controllable to rotate the blade to a supply position to enable material to be supplied from the blade to the additive manufacturing platform. The blade and the plurality of distribution elements are arranged such that during rotation: the blade provides a dose of material from the material supply module for supply to the additive manufacturing platform, and at least one of the plurality of distribution elements distributes the material within the material supply module so that the blade supplies a substantially uniform dose of material to the additive manufacturing platform along the length of the blade.

[0006] The two powder feeding mechanism solutions listed above are typical solutions, and technical solutions for supplying powder to the forming platform will continue to be developed. Summary of the Invention

[0007] The purpose of this application is to provide a powder stirring and conveying mechanism and additive manufacturing equipment, in the hope of reducing manufacturing and maintenance costs.

[0008] In a first aspect of the present application, a powder stirring and conveying mechanism is provided for supplying powder to a forming platform of an additive manufacturing device, wherein the powder stirring and conveying mechanism comprises: a shell; a stirring chamber located in the shell and used to hold powder, the stirring chamber having a discharge port located at an upper portion of the shell, the discharge port having a first edge portion, and the first edge portion being configured to be able to dock with the forming platform; an agitator, which is at least partially located in the stirring chamber and can be driven to rotate in a forward and reverse direction, the agitator comprising a main shaft and a plurality of stirring blades fixed to the main shaft; a powder supply plate, which is configured to stir the powder The powder in the mixing chamber is transported to the discharge port, the powder supply plate is rotatably arranged in the mixing chamber and includes a main body capable of supporting powder and at least one mounting arm extending from the main body, and the at least one mounting arm is rotatably arranged on the main shaft; the agitator is configured to contact the powder supply plate from one side of the powder supply plate and push the powder supply plate to rotate in the forward direction in the mixing chamber during forward rotation, and to contact the powder supply plate from the other side of the powder supply plate and push the powder supply plate to rotate in the reverse direction in the mixing chamber during reverse rotation.

[0009] According to the above scheme, by separating the agitator and the powder supply plate, it can not only facilitate the daily maintenance of the mechanism, but also the agitator can be designed with a larger swing range as needed; and because the powder supply plate in this case is not directly connected to the drive source, the power consumption is smaller during the entire working process.

[0010] In combination with the first aspect, in certain embodiments of the first aspect, the plurality of stirring blades are configured to contact the powder supply plate during the forward and reverse rotations.

[0011] According to the above solution, a plurality of stirring blades contact the powder supply plate, which can stably promote the rotation of the powder supply plate, thereby improving the stability of the powder supply plate in supplying powder.

[0012] In combination with the first aspect, in certain embodiments of the first aspect, the plurality of mounting arms are rotatably coupled to the main shaft via at least one bearing.

[0013] In combination with the first aspect, in certain embodiments of the first aspect, there are multiple mounting arms, and an opening is formed between two adjacent mounting arms.

[0014] According to the above solution, excess powder on the powder supply plate can fall back into the stirring chamber through the openings, thereby preventing the powder from being scattered everywhere.

[0015] In combination with the first aspect, in certain embodiments of the first aspect, the stirring chamber has an inlet located at the lower part of the shell, and the plurality of stirring blades are configured to disperse the powder fed into the stirring chamber from the inlet to both sides of the inlet.

[0016] In combination with the first aspect, in certain embodiments of the first aspect, the single rotation angle of the agitator in both forward and reverse rotations is 540°.

[0017] In combination with the first aspect, in certain embodiments of the first aspect, the discharge port has a second edge portion, and the second edge portion is opposite to the first edge portion; the rotation of the powder supply plate in the stirring chamber includes rotation between a first position and a second position; in the first position, the powder supply plate is close to the first edge portion; in the second position, the powder supply plate is close to the second edge portion.

[0018] According to the above solution, the powder supply plate can pass through the entire interior of the stirring chamber when rotating between the first position and the second position, so that there is no "dead zone" in the stirring chamber, and the utilization rate of the stirring chamber is effectively improved.

[0019] In combination with the first aspect, in certain embodiments of the first aspect, the rotation of the powder supply plate in the stirring chamber includes rotation between a first position and an origin position; the first edge portion is provided with a mechanical limiting mechanism, and the mechanical limiting mechanism includes a pair of blocks; in the origin position, the powder supply plate contacts the pair of blocks.

[0020] According to the above scheme, the use of a mechanical limit mechanism can help the powder supply plate identify the origin position, avoid accidents such as collisions, and the mechanical limit is stable and reliable, with extremely low maintenance costs.

[0021] In combination with the first aspect, in certain embodiments of the first aspect, the stirring chamber includes an arcuate inner wall surface connecting the first edge portion and the second edge portion, and the main body contacts or approaches the arcuate inner wall surface when rotating.

[0022] In combination with the first aspect, in certain embodiments of the first aspect, the powder stirring and conveying mechanism further includes: a powder collection chamber, which is located in the shell and arranged side by side with the stirring chamber, and the powder collection chamber is docked with the second edge portion.

[0023] In combination with the first aspect, in certain embodiments of the first aspect, the powder stirring and conveying mechanism further includes: a heating module, which is used to heat the powder in the stirring chamber.

[0024] In combination with the first aspect, in certain embodiments of the first aspect, the powder stirring and conveying mechanism also includes: a rotational drive device, which is arranged on the shell and located outside the stirring chamber, and the rotational drive device includes a motor, and the motor is connected to the main shaft to provide power to the stirrer to rotate in the forward and reverse directions.

[0025] The second aspect of the present application provides an additive manufacturing device, comprising: a powder stirring and conveying mechanism as described in the first aspect and any possible implementation of the first aspect; a forming platform, which can be raised and lowered relative to the discharge port; and a powder spreading mechanism, which is used to spread the powder provided by the powder supply plate onto the forming platform, the powder spreading mechanism comprising a powder spreading tool located above the forming platform and capable of moving laterally along the forming platform.

[0026] In combination with the second aspect, in certain embodiments of the second aspect, the powder spreading tool includes a powder spreading roller that can be driven to rotate, and the powder spreading roller extends longitudinally.

[0027] In combination with the second aspect, in certain embodiments of the second aspect, the powder stirring and conveying mechanisms are a pair and are respectively arranged on both sides of the forming platform.

[0028] Other advantages of the present invention will be described in detail in the following specific embodiments in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] FIG1 is a schematic structural diagram of an additive manufacturing device provided in one embodiment of the present application;

[0030] FIG2 is an overall schematic diagram of a powder stirring and conveying mechanism provided in one embodiment of the present application;

[0031] FIG3 is a schematic structural diagram of a stirring chamber provided in one embodiment of the present application;

[0032] FIG4 is a schematic structural diagram of an agitator provided in one embodiment of the present application;

[0033] FIG5 is a schematic structural diagram of a powder supply plate provided in one embodiment of the present application;

[0034] FIG6 is a schematic diagram of the powder supply plate of FIG5 combined with the agitator of FIG4;

[0035] FIG7 is an overall schematic diagram of a powder supply plate provided in an embodiment of the present application when in a first position;

[0036] FIG8 is a side view of a powder supply plate in a first position according to an embodiment of the present application;

[0037] FIG9 is an overall schematic diagram of a powder supply plate provided in an embodiment of the present application when in a second position;

[0038] FIG10 is a side view of a powder supply plate in a second position according to an embodiment of the present application;

[0039] FIG11 is a side view of a powder supply plate provided in an embodiment of the present application at an origin position;

[0040] FIG12 is a schematic diagram of the agitator and the powder supply plate of the present application in a first working state; wherein the powder supply plate is in a second position;

[0041] FIG13 is a schematic diagram of the stirrer and the powder supply plate of the present application in a second working state; wherein the powder supply plate is in the middle position one;

[0042] FIG14 is a schematic diagram of the agitator and the powder supply plate of the present application in a third working state; wherein the agitator blade rotates to the left side of the powder supply plate and contacts the powder supply plate;

[0043] FIG15 is a schematic diagram of the stirrer and powder supply plate of the present application in a fourth operating state; wherein the powder supply plate is in the middle position 2, and the powder spreading roller is located on the right side of the stirring chamber;

[0044] FIG16 is a schematic diagram of the stirrer and powder supply plate of the present application in a fifth operating state; wherein the powder supply plate is in the middle position 2, and the powder spreading roller moves to the left side of the stirring chamber;

[0045] FIG17 is a schematic diagram of the agitator and powder supply plate of the present application in a sixth operating state; wherein the powder supply plate is in the first position and the powder spreading roller is located on the left side of the agitator chamber;

[0046] FIG18 is a schematic diagram of the stirrer and powder supply plate of the present application in a seventh operating state; wherein the powder supply plate is in the first position and the powder spreading roller moves to the right side of the stirring chamber;

[0047] FIG19 is a schematic diagram of the agitator and the powder supply plate of the present application in an eighth working state; wherein the powder supply plate is at the origin position;

[0048] FIG20 is a schematic diagram of the stirrer and the powder supply plate of the present application in a ninth working state; wherein the powder supply plate is in the middle position three;

[0049] FIG21 is a schematic diagram of the stirrer and powder supply plate of the present application in the tenth working state; wherein the stirring blade rotates to the right side of the powder supply plate and contacts the powder supply plate;

[0050] FIG22 is a schematic diagram of the stirrer and the powder supply plate of the present application in an eleventh working state; wherein the powder supply plate is in the first position;

[0051] Among them: 100, additive manufacturing equipment; 1, feeding pipe; 2, forming platform; 3, powder stirring and conveying mechanism; 4, powder spreading mechanism; 41, powder spreading roller; 31, shell; 32, stirring chamber; 33, powder collecting chamber; 34, agitator; 35, powder supply plate; 36, rotary drive device; 321, discharge port; 3211, first edge portion; 3212, second edge portion; 3213, arc-shaped inner wall surface; 322, feed port; 351, main body; 352, mounting arm; 353, opening; 38, mechanical limiting mechanism; 381, stopper. DETAILED DESCRIPTION

[0052] The technical solution of this application will be clearly described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative work are within the scope of protection of this application.

[0053] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application.

[0054] It should be noted that the directional terms such as "upper", "lower", "left", "right", "horizontal", and "longitudinal" described in the embodiments of the present application are described based on the angles shown in the accompanying drawings and should not be understood as limiting the embodiments of the present application. In addition, in the context, it should be understood that when it is mentioned that one element is connected to another element, it can not only be directly connected to the other element, but also be indirectly connected to the other element through an intermediate element.

[0055] The powder stirring and conveying mechanism and additive manufacturing equipment proposed in the embodiments of the present application can be applied to additive manufacturing processes, and the powder material used in additive manufacturing can include at least one of polymers, metal powders or ceramic powders.

[0056] The terms "a" and "an" used in the following description are intended to indicate at least one of a particular element. In addition, as used herein, the term "include" means including but not limited to, and the term "comprising" means including but not limited to. The term "based on" means at least partially based on.

[0057] Referring to Figure 1, Figure 1 is a schematic diagram of the structure of an additive manufacturing device provided in an embodiment of the present application. The additive manufacturing device 100 includes a pair of feeding pipes 1 extending vertically, a forming platform 2, a pair of powder stirring and conveying mechanisms 3, and a powder spreading mechanism 4. The forming platform 2 is located between the pair of powder stirring and conveying mechanisms 3, and the three are arranged in a transverse direction (in this example, "transverse" refers to the left and right direction). The powder spreading mechanism 4 can translate between a forming platform 2 and a pair of powder stirring and conveying mechanisms 3 in a transverse direction.

[0058] Each feeding pipe 1 is connected to a powder mixing and conveying mechanism 3 at its upper portion and to a powder supply bin (not shown) at its lower portion. To continuously deliver powder from the supply bin to the pair of powder mixing and conveying mechanisms 3, a mechanical transmission mechanism is provided between the two. Typically, such a mechanical device is a conveyor belt or screw conveyor. In this example, a screw conveyor is preferably used for spiral feeding to achieve uniform powder delivery to the powder mixing and conveying mechanisms 3.

[0059] The forming platform 2 is often used to support printing operations, and its material and structure need to be selected according to the specific printing model and usage scenario; the forming platform 2 is usually a metal platform, but can also be a ceramic platform, a glass platform, a plastic platform, etc. When each layer of powder is spread on the forming platform 2, a printing operation is performed, after which the forming platform 2 will drop to a certain height and wait for the next powder spreading operation. In some embodiments, the forming platform is set to be slightly lower than the powder output position of the powder stirring and conveying mechanism. In these embodiments, the forming platform will not drop at the beginning of the printing operation, but will only start to drop after multiple powder spreading actions to fill the gap between the forming platform and the powder output position, so that the powder layer on the forming platform is flush with the powder output position.

[0060] The powder spreading mechanism 4 evenly spreads the powder from the stirring and conveying mechanism 3 onto the building platform 2. In this example, one function of the powder spreading mechanism 4 is to push excess powder delivered by the stirring and conveying mechanism 3 back into the stirring chamber of the stirring and conveying mechanism 3. A second function of the powder spreading mechanism 4 is to evenly spread an appropriate amount of powder delivered by the stirring and conveying mechanism 3 onto the building platform. The powder spreading mechanism 4 includes at least one powder spreading tool. In this example, the powder spreading tool comprises a rotating powder spreading roller 41 extending longitudinally. The roller surface of the powder spreading roller 41 is typically made of a highly elastic, wear-resistant material such as rubber or polyurethane. The rotation of the powder spreading roller 41 spreads and disperses the powder. Furthermore, the rotation speed and direction of the powder spreading roller can be adjusted to accommodate the dispersion requirements of different powder materials. In this example, the powder spreading roller 41 is capable of reciprocating and lateral translation between the stirring and conveying mechanism 3 and the building platform 2. In some embodiments, the powder spreading roller 41 can be replaced by a scraper.

[0061] Referring to Figures 2 and 3, the powder stirring and conveying mechanism 3 includes a housing 31, a stirring chamber 32, a powder collecting chamber 33, an agitator 34, and a powder supply plate 35. The stirring chamber 32 and the powder collecting chamber 33 are both located in the housing 31 and arranged side by side in the horizontal direction. The stirring chamber 32 and the powder collecting chamber 33 are both capable of retaining powder. The agitator 34 is at least partially located in the stirring chamber 32 and can be driven by a rotary drive device 36 to rotate in forward and reverse directions. In this example, the rotary drive device 36 is mounted on the outer wall surface of the housing 31, and the rotary drive device 36 may include a motor. The powder supply plate 35 is rotatably arranged in the stirring chamber 32.

[0062] The stirring chamber 32 has a discharge port 321 located at the upper portion of the housing 31. The discharge port 321 has a first edge portion 3211 and a second edge portion 3212 that oppose each other, and an arcuate inner wall surface 3213 connecting the first edge portion 3211 and the second edge portion 3212. The first edge portion 3211 and the second edge portion 3212 both extend longitudinally. The first edge portion 3211 can interface with the molding platform 2, and the powder collection chamber 33 interfaces with the second edge portion 3212.

[0063] The stirring chamber 32 has an inlet 322 located at the lower portion of the housing 31. The upper portion of the feeding pipe 1 is connected to the inlet 322, and the powder material can enter the stirring chamber 32 through the inlet 322. A heating module (not shown) is also provided at the lower portion of the housing 31. The heating module is coated on the outer wall of the stirring chamber 32 to heat the powder in the stirring chamber 32. The heating module can keep the powder material in the stirring chamber 32 at a certain temperature.

[0064] Referring to Figure 4, the agitator 34 includes a main shaft 341 extending in the longitudinal direction and a plurality of stirring blades 342 fixed to the main shaft 341; the motor of the rotary drive device 36 is in transmission connection with the main shaft 341 to provide the main shaft 341 with power for rotating in the forward and reverse directions, and can simultaneously drive the plurality of stirring blades 342 to rotate in the forward and reverse directions. The stirring blades 342 are spiral or flat spiral, and are configured to disperse the powder fed into the stirring chamber 34 from the feed port 322 to both sides of the feed port 322, so that the powder is evenly distributed in the stirring chamber 34; in addition, the plurality of stirring blades 342 can also push the powder supply plate 35 to rotate within a certain period of time. In this example, the agitator 34 can rotate in the forward and reverse directions under the drive of the rotary drive device 36.

[0065] Referring to Figure 5 , the powder supply plate 35 includes a main body 351 capable of supporting powder and a plurality of mounting arms 352 extending from the main body 351. An opening 353 is formed between adjacent mounting arms 352. These openings 353 not only allow powder that falls from the main body 351 to return to the stirring chamber 32, but also help reduce the weight of the powder supply plate 35, thereby alleviating the burden on the agitator 34. The powder supply plate 35 is configured to transport powder within the stirring chamber 32 to the first edge 3211 of the discharge port 321.

[0066] 6 , a plurality of mounting arms 352 are rotatably mounted on the main shaft 341 . In this example, the plurality of mounting arms 352 are rotatably coupled to the main shaft 341 via a plurality of bearings 354 . The main body 351 contacts or approaches the arcuate inner wall surface 3213 during rotation.

[0067] As shown in Figures 7-10, the rotation of the powder supply plate 35 within the stirring chamber 32 includes rotation between a second position, a first position, and an origin position. As shown in Figures 7 and 8, the powder supply plate 35 is in the first position, close to the first edge portion 3211. As shown in Figures 9 and 10, the powder supply plate 35 is in the second position, close to the second edge portion 3212. By virtue of the rotation of the powder supply plate 35 between the first and second positions, the powder within the stirring chamber 32 can be continuously transported to the discharge port 321 for transfer to the forming platform 2 by the powder spreading roller 41.

[0068] During operation of the agitator 34, during forward rotation, the agitator 34 can contact the powder supply plate 35 from one side thereof and propel the powder supply plate 35 to rotate in the forward direction within the stirring chamber 32. Furthermore, during reverse rotation, the agitator 34 can contact the powder supply plate 35 from the other side thereof and propel the powder supply plate 35 to rotate in the reverse direction within the stirring chamber 32. In this example, the plurality of agitating blades 342 on the agitator 34 directly contact the powder supply plate 35 for a period of time during both forward and reverse rotation, thereby propel the powder supply plate 35 to rotate.

[0069] 2 and 3 , the first edge portion 3211 of the discharge port 321 is provided with a mechanical limiting mechanism 38 , and the mechanical limiting mechanism 38 includes a pair of stoppers 381 .

[0070] As shown in Figure 11, at this time the powder supply plate 35 is in the origin position, and the powder supply plate 35 contacts a pair of blocks 381. The use of mechanical limiting here can, on the one hand, prevent the powder supply plate 35 from crossing the first edge portion 3211 of the discharge port 321 and causing accidents such as collision with the powder roller 41, and the mechanical limiting is stable and reliable, with extremely low maintenance costs. On the other hand, by setting the mechanical limit origin position. In some embodiments, when the powder supply plate 35 contacts the mechanical limiting mechanism 38, the change in the electrical signal caused by the motor being stalled can be used to identify whether the powder supply plate 35 has reached the origin position. In other preferred embodiments, a proximity switch sensor can be set at the origin position to identify whether the powder supply plate 35 has reached the origin position. During operation, the powder mixing and conveying mechanism's shaft, agitator 34, evenly distributes the powder overflowing from the bottom feed inlet 322 to both sides, distributing it evenly along the longitudinal length of the mixing chamber 32. The agitator 34 then reciprocates to ensure uniform heating of the powder. As the agitator 34 rotates back and forth, the powder supply plate 35, acting upon the thrust from the contact points of the agitator's blades 342 and the force of gravity, also swings back and forth. The following describes the operating process of the agitator 34 and powder supply plate 35:

[0071] As shown in Figure 12, the powder supply plate 35 at this position is in the second working position. The powder supply plate 35 is close to the second edge portion 3212 of the discharge port 321. After driving the agitator 34 counterclockwise (i.e., in the reverse direction, the same below) to rotate a certain angle, the stirring blade 342 of the agitator 34 leaves the powder supply plate 35; the powder supply plate 35 is no longer affected by the support force of the stirring blade 342, and is only affected by its own gravity and the resistance of the powder at the bottom. As shown in Figure 13, the powder supply plate 35 moves to the middle position by itself.

[0072] After that, the stirring blade 342 of the stirrer 34 continues to rotate counterclockwise until it moves to the left side of the powder supply plate 35 and contacts the powder supply plate 35; as shown in FIG14 , the stirring blade 342 will continue to rotate counterclockwise and provide a thrust to the powder supply plate 35, so that the powder supply plate 35 drives the powder P at the bottom of the stirring chamber 32 to move to the middle position 2 as shown in FIG15 . In this middle position 2, the stirrer 34 stops rotating, and the powder supply plate 35 is supported by the stirring blade 342 and stops; as shown in FIG16 , at this time, the driving powder roller 41 moves horizontally from right to left, so that the powder supply plate 35 The portion of powder P1 on the plate 35 that exceeds the plane of the discharge port 321 will be removed from the powder supply plate 35 and sent back to the stirring chamber 32; as shown in Figure 17, after the powder roller 41 removes the powder P1, the stirring blade 342 will continue to rotate counterclockwise and push the powder supply plate 35 and the powder P2 thereon to the first position. As shown in Figure 18, in this first position, the agitator 34 stops rotating, and the powder supply plate 35 supported by the stirring blade 342 will stop, driving the powder roller 41 to move horizontally from left to right and transfer the powder P2 on the powder supply plate 35 to the forming platform 2. As shown in Figure 19, when the powder roller 41 leaves the stirring chamber 32, the agitator 34 continues to rotate counterclockwise to push the powder supply plate 32, causing the powder supply plate 35 to contact a pair of blocks 381 of the mechanical limit mechanism, that is, the powder supply plate 35 is at the origin. In other embodiments, the step of positioning the powder supply plate 35 at the origin may be performed once after a certain number of powder conveying operations, or may be performed only during power-on self-test.

[0073] After the powder supply plate 35 returns to the original position, the agitator 34 will change to clockwise (i.e., forward direction). At this time, the powder supply plate 35 is affected by gravity and also rotates clockwise until it reaches the middle position three as shown in Figure 20 (this middle position three may be at the same position as the middle position one, or it may be different. It is affected by the gravity on the powder supply plate 35 and the powder resistance at the bottom of the stirring chamber). It is blocked by the powder at the bottom of the stirring chamber and stops moving. The powder supply plate 35 will stay at this middle position three. At this time, the agitator 34 continues to rotate clockwise until it rotates to the right side of the powder supply plate 35, as shown in Figure 21; at this time, the stirring blade 342 of the agitator 34 contacts the powder supply plate 35; thereafter, the agitator 34 continues to rotate clockwise and pushes the powder supply plate 35 to move clockwise until the powder supply plate 35 returns to the second position as shown in Figure 22.

[0074] In this way, the powder supply plate 35 completes a single powder conveying process. During this process, the powder supply plate 35 rotates 180° counterclockwise and 180° clockwise, respectively, and the agitator 34 rotates 540° counterclockwise and 540° clockwise, respectively. During the rotation of the powder supply plate 35, the rotational force is partially derived from its own gravity and partially from the propulsion of the agitator blades 342. The rotation is stable.

[0075] In this case, a set of transmission mechanisms can be used to complete the processes of powder stirring and powder lifting and feeding, thereby reducing equipment manufacturing costs, maintenance costs and customer production costs; and a mechanical limit method is used to identify the direction of the powder supply plate 35 to avoid accidents such as collisions, and the mechanical limit is stable and reliable, with minimal maintenance costs.

[0076] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above embodiments. The above embodiments and descriptions are only for illustrative purposes. Various changes and improvements may be made to the present application without departing from the spirit and scope of the present application. The scope of protection claimed in the present application is defined by the appended claims, the description and their equivalents.

Claims

1. A powder stirring and conveying mechanism for supplying powder to a forming platform of an additive manufacturing device, characterized in that, The powder stirring and conveying mechanism comprises: case; a stirring chamber, which is located in the shell and can hold powder, the stirring chamber having a discharge port located at the upper part of the shell, the discharge port having a first edge portion, and the first edge portion is configured to be able to dock with the forming platform; an agitator, which is at least partially located in the agitation chamber and can be driven to rotate in a forward direction and a reverse direction, the agitator comprising a main shaft and a plurality of agitation blades fixed to the main shaft; A powder supply plate, which is configured to transport the powder in the stirring chamber to the discharge port, the powder supply plate is rotatably disposed in the stirring chamber and includes a main body capable of supporting powder and at least one mounting arm extending from the main body, and the at least one mounting arm is rotatably disposed on the main shaft; the agitator is configured to contact the powder supply plate from one side of the powder supply plate and push the powder supply plate to rotate in the forward direction in the stirring chamber during forward rotation, and to contact the powder supply plate from the other side of the powder supply plate and push the powder supply plate to rotate in the reverse direction in the stirring chamber during reverse rotation.

2. The powder stirring and conveying mechanism according to claim 1, characterized in that, There are multiple installation arms, and an opening is formed between two adjacent installation arms.

3. The powder stirring and conveying mechanism according to claim 1, characterized in that, The stirring chamber has a material inlet located at the lower part of the shell, and the plurality of stirring blades are configured to disperse the powder fed into the stirring chamber from the material inlet to both sides of the material inlet.

4. The powder stirring and conveying mechanism according to claim 1, wherein The discharge port has a second edge portion, and the second edge portion is opposite to the first edge portion; the rotation of the powder supply plate in the stirring chamber includes rotation between a first position and a second position; In the first position, the powder supply plate is close to the first edge portion; in the second position, the powder supply plate is close to the second edge portion.

5. The powder stirring and conveying mechanism according to claim 4, characterized in that, The rotation of the powder supply plate in the stirring chamber includes rotation between a first position and an origin position; the first edge portion is provided with a mechanical limiting mechanism, and the mechanical limiting mechanism includes a pair of blocks; in the origin position, the powder supply plate contacts the pair of blocks.

6. The powder stirring and conveying mechanism according to claim 4, wherein, The stirring chamber comprises an arc-shaped inner wall surface connecting the first edge portion and the second edge portion, and the main body contacts or approaches the arc-shaped inner wall surface when rotating.

7. The powder stirring and conveying mechanism according to claim 4, characterized in that, Also includes: A powder collecting chamber is located in the shell and arranged side by side with the stirring chamber, and the powder collecting chamber is butted against the second edge portion.

8. The powder stirring and conveying mechanism according to claim 1, wherein Also includes: A heating module is used to heat the powder in the stirring chamber.

9. The powder stirring and conveying mechanism according to claim 1, wherein Also includes: The rotary drive device is arranged on the shell and located outside the stirring chamber. The rotary drive device includes a motor, which is connected to the main shaft to provide the stirrer with power for rotating in the forward and reverse directions.

10. An additive manufacturing device, characterized in that, include: A powder stirring and conveying mechanism as described in any one of claims 1 to 9; A molding platform, which can be raised and lowered relative to the discharge port; as well as Powder spreading mechanism, which is used to spread the powder provided by the powder supply plate onto the forming platform. The powder spreading mechanism includes a powder spreading tool located above the forming platform and capable of moving laterally along the forming platform.

11. The additive manufacturing device according to claim 10, wherein, The powder spreading tool includes a powder spreading roller that can be driven to rotate, and the powder spreading roller extends longitudinally.

12. The additive manufacturing device according to claim 10, wherein The number of the powder stirring and conveying mechanisms is one pair and they are respectively arranged on both sides of the forming platform.

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