Powder spreading apparatus and powder spreading control method

Abstract

The embodiment of the application relates to the technical field of 3D printing powder laying, and discloses a powder laying device and a powder laying control method, the powder laying device comprising a powder laying platform, a powder laying device, a first driving device and a second driving device. The powder laying platform is used for laying printing materials, the powder laying device comprises a cantilever and a powder laying roller, the cantilever is slidingly arranged on the powder laying platform, the powder laying roller is rotationally arranged on the cantilever, the first driving device drives the powder laying roller to rotate, and the second driving device drives the cantilever to slide. Through the above mode, the embodiment of the application realizes independent adjustment of the translational speed and the rotating speed of the powder laying roller, so that a good powder laying effect is achieved.

Description

TECHNICAL FIELD

[0001] The embodiment of the present application relates to the field of 3D printing technology, in particular to a powder laying device and a powder laying control method. BACKGROUND

[0002] A 3D printer is an additive manufacturing equipment for rapid prototyping. The powder laying printing mode has been widely used in 3D printing equipment such as selective laser sintering, selective laser melting, binder jetting technology. The powder laying device with a powder laying roller has a good powder laying effect on materials with relatively poor fluidity such as high polymer materials, metal and high polymer composite materials, and has been applied to 3D printing equipment with printing materials containing high polymer materials such as selective laser melting, binder jetting technology.

[0003] At present, the powder laying roller driving device and transmission mechanism are arranged on the powder laying assembly, which has the defects of large size and complex transmission structure, and the mode of rotating the powder laying roller by moving the powder laying assembly is limited by the fixed transmission ratio, so that the speed of the powder laying roller cannot be adjusted, which has the defects of single use parameter and narrow application range, and cannot meet the laying of printing materials of different types and particle sizes. SUMMARY

[0004] In view of the above problems, the embodiment of the present application provides a powder laying device and a powder laying control method, which can independently adjust the translational speed and rotational speed of the powder laying roller to achieve good powder laying effect.

[0005] According to an aspect of the embodiment of the present application, a powder laying device is provided, which comprises a powder laying platform, a powder laying device, a first driving device and a second driving device. The powder laying platform is used for laying printing materials; the powder laying device comprises a cantilever and a powder laying roller, the cantilever is slidingly arranged on the powder laying platform along a preset moving direction, and the powder laying roller is rotationally connected to the cantilever; the second driving device is arranged on the powder laying platform, the second driving device is connected with the cantilever, and the second driving device is used for driving the cantilever to move relative to the powder laying platform along the preset moving direction at a preset moving speed, so that the cantilever drives the powder laying roller to smooth the printing materials on the powder laying platform; the first driving device is connected with the powder laying roller, and the first driving device is used for driving the powder laying roller to rotate relative to the powder laying platform in a preset rotating direction at a preset rotating speed, so that the powder laying roller compacts the printing materials on the powder laying platform, and when the powder laying roller rotates in the preset rotating direction, the linear velocity direction of the powder laying roller towards the bottom edge of the powder laying platform is the same as the preset moving direction.

[0006] The powder spreading device is driven to move relative to the powder spreading platform by the second driving device, and the powder spreading roller is driven to rotate relative to the powder spreading platform by the first driving device alone. The driving force of the powder spreading roller is external, so that the rotation speed of the powder spreading roller is not limited by the moving speed of the powder spreading device, the situation that the rotation speed of the powder spreading roller is limited during the powder spreading process is reduced, the printing material is compacted during the powder spreading process, and good powder spreading effect is achieved.

[0007] In an optional mode, the preset moving speed is positively correlated with the preset rotation speed.

[0008] The preset rotation speed of the powder spreading roller is positively correlated with the preset moving speed, so that the rotation speed of the powder spreading roller can be better adjusted to ensure good powder spreading effect.

[0009] In an optional mode, the first driving device comprises a first driving member, a first driving wheel, a first driven wheel and a first flexible transmission member. The first driving wheel and the first driven wheel are both rotationally arranged on the powder spreading platform, and the first driving wheel and the first driven wheel are arranged in a spaced manner along the preset moving direction. The first flexible transmission member is sleeved between the first driving wheel and the first driven wheel. The output shaft of the first driving member is connected with the first driving wheel, and the first driving member is used for moving the first flexible transmission member through the first driving wheel. The powder spreading roller is engaged with the first flexible transmission member, so that the powder spreading roller rotates with the movement of the first flexible transmission member.

[0010] The first driving device is arranged on the powder spreading platform, the occupied space and weight of the powder spreading device are reduced, the structural cost and operation energy consumption are reduced, and the stability of powder spreading is improved.

[0011] In an optional mode, a bearing seat is arranged on the cantilever, a bearing is arranged in the bearing seat, one end of the powder spreading roller has a transmission shaft, the transmission shaft is rotationally connected to the bearing seat through the bearing, a first transmission wheel is arranged on the transmission shaft, and the first transmission wheel is engaged with the first flexible transmission member.

[0012] The transmission shaft and the bearing are used to limit the rotation of the powder spreading roller on the bearing seat, the vibration of the powder spreading roller caused by the first flexible transmission member during the transmission process is reduced, and the powder spreading is more stable.

[0013] In an optional mode, the first transmission wheel is engaged with the inner side surface of the first flexible transmission member, a tensioning wheel is also rotationally arranged on the bearing seat, the tensioning wheel is arranged on the outer side of the first transmission wheel, and the tensioning wheel is pressed against the outer side surface of the first flexible transmission member.

[0014] The tensioning wheel presses the first flexible transmission member inward, increases the contact area of the inner side of the first flexible transmission member and the first transmission wheel, thereby increasing the number of teeth of the first transmission wheel and the inner side of the first flexible transmission member, and further tightening the first flexible transmission member, and improving the stability of the transmission.

[0015] In an optional manner, the number of the tensioning wheels is two, and the tensioning wheels are respectively located on two sides of the first transmission wheel along the preset moving direction.

[0016] The two tensioning wheels increase the acting force of the first flexible transmission member on both sides of the first transmission wheel when the first flexible transmission member operates, thereby improving the stability of the transmission and the service life of the first flexible transmission member.

[0017] In an optional manner, the powder spreading device comprises a first bearing seat and a second bearing seat, the first bearing seat and the second bearing seat are fixedly arranged below the cantilever, the first bearing seat and the second bearing seat are respectively provided with bearings, the heights of bearing hole positions are consistent, and the powder spreading roller is rotationally connected between the bearings of the first bearing seat and the second bearing seat.

[0018] The two ends of the powder spreading roller are respectively connected with the bearings, the connection of the two ends of the powder spreading roller reduces the vibration generated when the powder spreading roller rotates, and the stability of the powder spreading roller is improved, the consistent height of the bearing hole positions makes the powder spreading roller parallel to the powder spreading platform, and the printing material is pressed into a plane.

[0019] In an optional manner, the second driving device comprises a second driving member, a second driving wheel, a second driven wheel and a second flexible transmission member, the second driving wheel and the second driven wheel are rotationally arranged on the powder spreading platform, the second driving wheel and the second driven wheel are spaced apart along the preset moving direction, the second flexible transmission member is sleeved between the second driving wheel and the second driven wheel, the output shaft of the second driving member is connected with the second driving wheel, and the second driving member is used for moving the second flexible transmission member through the second driving wheel; the cantilever is fixedly connected with the second flexible transmission member, so that the cantilever moves with the second flexible transmission member.

[0020] The transmission structure is formed by arranging the second driving wheel, the second driven wheel and the second flexible transmission member, the first driving member drives the second flexible transmission member to drive the cantilever to move along a fixed path relative to the powder spreading platform, and the structure is simple and convenient to install.

[0021] In an optional manner, a guide rail is arranged on the powder spreading platform along the preset moving direction, a sliding block is arranged on the cantilever, and the sliding block is slidingly connected to the guide rail.

[0022] The powder laying device can reduce the interference of the vibration of the flexible transmission member on the powder laying effect by moving the sliding block on the guide rail, so that the powder laying is more stable.

[0023] According to another aspect of the embodiment of the present application, a powder laying control method is provided, including: obtaining the preset moving speed and the preset rotating speed; calculating the output rotating speed of the second driving device according to the transmission ratio between the second driving device and the powder laying device and the preset moving speed; calculating the output rotating speed of the first driving device according to the transmission ratio between the first driving device and the powder laying roller and the preset rotating speed; controlling the second driving device to operate in a first rotating direction to drive the cantilever to move in a first direction in the preset moving direction, and controlling the first driving device to operate in a second rotating direction to drive the powder laying roller to rotate in a first direction in the preset rotating direction, until the cantilever moves to a first target position, wherein when the powder laying roller rotates in the first direction, the linear velocity direction of the powder laying roller towards the bottom edge of the powder laying platform is the same as the first direction; controlling the second driving device to operate in a third rotating direction to drive the cantilever to move in a second direction in the preset moving direction, and controlling the first driving device to operate in a fourth rotating direction to drive the powder laying roller to rotate in a second direction in the preset rotating direction, until the cantilever moves to a second target position, wherein when the powder laying roller rotates in the second direction, the linear velocity direction of the powder laying roller towards the bottom edge of the powder laying platform is the same as the second direction, the third rotating direction is opposite to the first rotating direction, the second direction is opposite to the first direction, and the second direction is opposite to the first direction; jumping to the control of the second driving device to operate in the first rotating direction to drive the cantilever to move in the first direction in the preset moving direction, and the control of the first driving device to operate in the second rotating direction to drive the powder laying roller to rotate in the first direction in the preset rotating direction, until the cantilever moves to the first target position, until the powder laying is completed.

[0024] The powder laying control method drives the cantilever to move back and forth relative to the powder laying platform by the second driving member, and drives the powder laying roller to rotate relative to the powder laying platform according to the moving direction of the cantilever by the first driving member, so that the rotation of the powder laying roller is externalized, the rotating speed of the powder laying roller is not limited by the moving speed of the powder laying device, and the powder laying process is improved.

[0025] The above description is only a summary of the technical solutions of the present application. In order to enable one skilled in the art to better understand the technical means of the present application, the present application can be implemented according to the content of the description, and in order to enable the above and other purposes, characteristics and advantages of the present application to be more obvious and easy to understand, the following specific embodiments of the present application are described. BRIEF DESCRIPTION OF DRAWINGS

[0026] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a description of the preferred embodiments, and are not meant to limit the present application. Moreover, the same reference numerals are used throughout the various drawings to designate identical parts. In the drawings:

[0027] Figure 1 A structural schematic diagram of a powder laying device provided by an embodiment of the present application is shown in FIG. 4.

[0028] Figure 2 A structural schematic diagram of the transmission engagement between the first driving wheel and the first flexible transmission member in the powder laying device provided by an embodiment of the present application is shown in FIG. 5.

[0029] Figure 3a A structural schematic diagram of the powder laying device provided by an embodiment of the present application is shown in FIG. 6.

[0030] Figure 3b A sectional structural schematic diagram of the powder laying device provided by an embodiment of the present application is shown in FIG. 7.

[0031] Figure 4 A structural schematic diagram of the tension wheel in the powder laying device provided by an embodiment of the present application is shown in FIG. 8.

[0032] Figure 5 A structural schematic diagram of the connection between the guide rail and the sliding block in the powder laying device provided by an embodiment of the present application is shown in FIG. 9.

[0033] Figure 6 A flowchart of the powder laying control method provided by an embodiment of the present application is shown in FIG. 10.

[0034] The reference numerals in the detailed description are as follows:

[0035] 100, powder laying device;

[0036] 110, powder laying platform; 111, guide rail; 112, sliding block;

[0037] 120, powder laying device; 121, cantilever; 1211, bearing seat; 122, powder laying roller; 1221, transmission shaft; 1222, first transmission wheel; 1223, tension wheel; 1231, first bearing seat; 1232, second bearing seat; 1233, bearing;

[0038] 130, first driving device; 131, first driving member; 132, first driving wheel; 133, first driven wheel; 134, first flexible transmission member;

[0039] 140, second driving device; 141, second driving member; 142, second driving wheel; 143, second driven wheel; 144, second flexible transmission member. DETAILED DESCRIPTION

[0040] The embodiments of the present application will be described in detail below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical scheme of the present application, and therefore only serve as examples, but cannot be used to limit the protection scope of the present application.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the specification herein is for describing particular embodiments only and is not intended to be limiting of the application; the use of the terms "include," "have," or "comprise" and variations thereof herein are intended to be equivalent to the term "comprising"; and the use of the term "about" in relation to a geographic area is intended to be equivalent to the term "approximately".

[0042] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is two or more, unless otherwise explicitly and specifically limited.

[0043] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The occurrence of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily independent or alternative embodiments to each other. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0044] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of existence of A, existence of A and B, and existence of B. In addition, the character " / " in this paper generally represents a "or" relationship between the front and rear associated objects.

[0045] In the description of the embodiments of the present application, the term "multiple" refers to two or more (including two), and similarly, "multiple groups" refers to two or more groups (including two groups), and "multiple pieces" refers to two or more pieces (including two pieces).

[0046] In the description of the embodiments of the present application, the orientations or positional relationships indicated by the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the embodiments of the present application.

[0047] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connecting", "connecting", "fixing" and the like should be understood in a broad sense, for example, can be fixed connection, can also be detachable connection, or integral; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0048] At present, in the field of 3D printing technology, the forming method has the problem of shrinkage of the workpiece, which is not only related to the characteristics of the material, but also related to the density of the powder to be sintered. Generally speaking, the density of the powder is about 70% of the full density, and the density of the formed part after sintering can reach more than 98% of the full density, so the change of the powder density during the forming process will cause the shrinkage of the formed part. In order to minimize the shrinkage of the formed part and obtain a formed part with higher quality, it is necessary to ensure that the powder has a higher density. Powder laying is one of the important printing methods in 3D printing sintering technology. In order to shorten the manufacturing cycle of the part, improve the forming efficiency, and at the same time ensure the quality of the formed part, it is one of the prerequisites for smooth sintering to ensure that the powder has a higher density during powder laying.

[0049] Common powder laying methods mainly include scraper type, powder laying roller type and moving hopper type, etc. Among them, the powder laying device of scraper type and powder laying roller type belongs to the lower supply type. The powder laying device of moving hopper type belongs to the upper supply type. Since the powder is not compacted, the density between the powder layers is small, resulting in a relatively sparse product organization structure of the formed part; for the powder laying device using a scraper to lay powder, although it can meet certain requirements, it also has problems such as uneven powder laying and low powder density, resulting in low surface quality of the formed part, and even the layers are difficult to bond, and sintering cannot continue; the powder laying roller not only moves horizontally but also rotates, which not only can lay the powder flat, but also can compact the powder more effectively.

[0050] In existing powder spreading devices, the spreading roller rotates by translating itself on the powder. Its rotational speed is directly proportional to the overall translational speed of the spreading device, and the speed ratio is fixed. In practical applications, the compaction effect of different types of powders is related to the rotational speed of the spreading roller. Therefore, the rotational speed of the spreading roller affects the compaction effect of the powder, and the rotational speed cannot be adjusted according to different powders, which poses a significant limitation to process development.

[0051] Based on the above considerations, in order to achieve better powder spreading effect by independently driving the powder spreading roller and adjusting its rotation speed, so that the powder spreading roller can be adjusted to different speeds according to the type of printing material, the inventors of this application propose a powder spreading device. The powder spreading device includes a powder spreading platform, a powder spreading device, a first driving device, and a second driving device. The printing material is spread on the powder spreading platform. The second driving device is used to drive the powder spreading device to translate relative to the powder spreading platform, so that the powder spreading device smooths the printing material on the powder spreading platform. The first driving device is used to drive the powder spreading device to rotate, so that the powder spreading device compacts the printing material. Moreover, the rotation speed of the powder spreading device can be adjusted by the first driving device according to different types of printing materials, and the moving speed of the powder spreading device can be adjusted by the second driving device.

[0052] The powder spreading equipment disclosed in this application can be used, but is not limited to, for powder spreading in 3D printing, and can also be used in the compaction process of any powder, solid particles and other materials.

[0053] Please see Figure 1 , Figure 1 This diagram illustrates a structural embodiment of the powder spreading device disclosed in this invention. The powder spreading device 100 includes a powder spreading platform 110, a powder spreading device 120, a first driving device 130, and a second driving device 140. The powder spreading platform 110 is used to spread printing materials. The powder spreading device 120 includes a cantilever 121 and a powder spreading roller 122. The cantilever 121 moves along a preset direction (e.g., ...). Figure 1 The powder spreading roller 122 (in the direction indicated by arrow A and the opposite direction) is slidably disposed on the powder spreading platform 110. The powder spreading roller 122 is rotatably connected to the cantilever 121; the second drive device 140 is disposed on the powder spreading platform and connected to the cantilever 121. The second drive device 140 is used to drive the cantilever 121 to move relative to the powder spreading platform 110 along a preset moving direction and at a preset moving speed, so that the cantilever 121 drives the powder spreading roller 122 to smooth the printed material on the powder spreading platform 110; the first drive device 130 is connected to the powder spreading roller 122 and is used to drive the powder spreading roller 122 to rotate relative to the powder spreading platform 110 in a preset rotating direction and at a preset speed, so that the powder spreading roller 122 compacts the printed material on the powder spreading platform 110. When the powder spreading roller 122 rotates in the preset rotating direction, its linear velocity direction toward the bottom edge of the powder spreading platform 110 is the same as the preset moving direction.

[0054] As shown in Figure 1 , the powder laying platform 110 can be provided with a groove for laying the printing material, the shape of the groove is not limited, and the printing material is laid in the groove. The cantilever 121 is horizontally arranged on the powder laying platform 110, and the powder roller 122 is installed on the lower side of the cantilever 121, so that the side surface of the powder roller 122 is in horizontal contact with the printing material. The second driving device 140 is installed on the powder laying platform 110 and can be connected with one end of the cantilever 121 away from the powder roller 122, so that the second driving device 140 drives the cantilever 121 to move on the powder laying platform in a preset direction.

[0055] The first driving device 130 can be connected with the rotating shaft of one end of the powder roller 122, and the first driving device can be installed on the powder laying platform 110 or the cantilever 121, as long as it can drive the powder roller 122 to rotate in a preset rotating direction at a preset rotating speed. In order to ensure that the linear speed direction of the bottom of the powder roller 122 is the same as the moving direction of the powder laying device 120, when the second driving device 140 drives the powder laying device 120 to move in the direction indicated by the arrow A in the figure, the first driving device 130 drives the powder roller 122 to rotate in the direction indicated by the arrow B in the figure, when the second driving device 140 drives the powder laying device 120 to move in the direction opposite to the direction indicated by the arrow A in the figure, the first driving device 130 drives the powder roller to rotate in the direction indicated by the arrow C in the figure, so that the cantilever 121 moves relative to the powder laying platform 110, and the powder roller 122 rotates and flattens and compacts the printing material. Figure 1 Figure 1 Figure 1

[0056] In use, the powder laying equipment 100 can be installed on a 3D printer, and can share a power supply with the 3D printer or work using a separate power supply. The 3D printer can control the powder laying equipment 100 to work through a controller. After the power is turned on, the controller controls the second driving device 140 to drive the cantilever 121 to move in the direction indicated by the arrow A in the figure, and controls the first driving device 130 to drive the powder roller 122 to rotate in the direction indicated by the arrow B in the figure. The right groove of the powder laying platform 110 is the discharge place, and when the cantilever 121 passes above the discharge place, the powder roller 122 pushes the printing material at the discharge place to the left groove of the powder laying platform 110 and flattens and compacts it, and when the cantilever 121 moves to the left end point, the controller controls the second driving device 140 to drive the cantilever 121 to move in the opposite direction indicated by the arrow A in the figure, and controls the first driving device 130 to drive the powder roller 122 to rotate in the direction indicated by the arrow C in the figure, so as to prevent the powder roller 122 from damaging the printing material plane, and when the cantilever 121 moves to the right end point, the controller controls the 3D printer to lay new printing material at the discharge place. The controller controls the powder laying equipment 100 and the 3D printer to cycle the above steps until the printing is completed. Figure 1 Figure 1

[0057] ​​​​​In the powder laying process, the powder laying roller 122 rotates while moving to push the printing material to the printing area to be laid flat and compacted, and the powder laying effect of the powder laying roller 122 is related to the moving speed of the powder laying device 120 and the friction coefficient of the surface of the printing material. Therefore, in actual application, the rotating speed of the powder laying roller 122 is adjusted according to the moving speed of the powder laying device 120 and the printing material.

[0058] The powder laying device 100 provided by the embodiment of the present application drives the powder laying device 120 to move relative to the powder laying platform 110 through the second driving device 140, and separately drives the powder laying roller 122 to rotate relative to the powder laying platform 110 through the first driving device 130. The driving force of the rotation of the powder laying roller 122 is external, so that the rotating speed of the powder laying roller 122 is not limited by the moving speed of the powder laying device 120, and the damage to the printing material plane caused by the limited rotating speed of the powder laying roller 122 in the powder laying process is reduced, so that the powder laying roller 122 compacts the printing material in the powder laying process, and good powder laying effect is achieved.

[0059] In the powder laying process, the relationship between the moving speed and the rotating speed of the powder laying roller 122 relative to the powder laying platform 110 is one of the important factors affecting the powder laying efficiency. In order to better adjust the preset moving speed and the preset rotating speed, according to some embodiments of the present application, the preset moving speed of the powder laying roller 122 is positively correlated with the preset rotating speed.

[0060] Since the smaller the curvature radius of the contact point between the powder laying roller 122 and the printing material is, the more unstable the motion of the contact point is, therefore, in the powder laying process, the related process parameters of the powder laying roller 122 should be considered comprehensively, and the curvature radius of the contact point between the powder laying roller 122 and the powder particles of the printing material should be increased as much as possible. When the cantilever 121 and the powder laying roller 122 move forward at a horizontal speed v and the powder laying roller 122 rotates at an angular speed ω, since the radius of the powder laying roller 122 is small, the powder laying roller 122 is analyzed as a rigid body, and the trajectory equation of the outermost point of the powder laying roller 122 is:

[0061]

[0062] In the above formula, v is the horizontal speed at which the powder laying roller 122 moves forward; ω is the angular speed at which the powder laying roller 122 rotates, the direction of the linear speed of the lowest point of the powder laying roller 122 is positive if it is the same as the forward direction of the powder laying roller 122, and negative otherwise; R is the radius of the powder laying roller 122; β is the included angle between the radius connecting the outermost point of the powder laying roller 122 and the center of the powder laying roller 122 and the radius connecting the lowest point of the powder laying roller 122 and the center of the powder laying roller 122. The curvature radius p of the trajectory of the outermost point of the powder laying roller 122 is:

[0063]

[0064] From the above formula, the radius of curvature p is related to the radius R of the powder roller 122, the horizontal speed, i.e., the moving speed v of the powder roller 122 relative to the powder platform 110, and the angular velocity ω of the rotation of the powder roller 122. In actual applications, in order to save costs, the size of the powder roller 122 is not easily changed, and thus the radius R of the powder roller 122 can be regarded as a constant value. Then, it can be analyzed that the preset rotating speed of the powder roller 122 is positively correlated with the preset moving speed. Therefore, when the preset moving speed of the powder roller 122 is increased in order to improve the powdering efficiency, the preset rotating speed of the powder roller 122 should also be increased to ensure the radius of curvature p of the movement track of the powder roller 122 required for good powdering effect, so that the rotating speed of the powder roller 122 can be better adjusted.

[0065] According to some embodiments of the present application, optionally, please continue to refer to Figure 1 , the first driving device 130 includes a first driving member 131, a first driving wheel 132, a first driven wheel 133, and a first flexible transmission member 134. The first driving wheel 132 and the first driven wheel 133 are both rotationally arranged on the powder platform 110, and the first driving wheel 132 and the first driven wheel 133 are arranged in a preset moving direction. The first flexible transmission member 134 is sleeved between the first driving wheel 132 and the first driven wheel 133. The output shaft of the first driving member 131 is connected with the first driving wheel 132, and the first driving member 131 is used to drive the first flexible transmission member 134 to move through the first driving wheel 132. The powder roller 122 is engaged with the first flexible transmission member 134, so that the powder roller 122 rotates with the movement of the first flexible transmission member 134.

[0066] As shown in Figure 1 , the first driving member 131 can be a motor, which is fixedly arranged on the powder platform 110. The output shaft of the motor is fixedly connected with the first driving wheel 132. The first driving wheel 132, the first driven wheel 133, and the first flexible transmission member 134 can be two pulleys and a transmission belt as shown in Figure 1 , or two sprockets and a transmission chain in other embodiments. Please refer to Figure 2 , Figure 2 , which shows the connection structure of the first driving wheel 132 and the first flexible transmission member 134. The inner side of the first flexible transmission member 134 is provided with a clamping tooth which is engaged and connected with the clamping tooth of the first driving wheel 132. The first driven wheel 133 and the powder roller 122 are also engaged with the first flexible transmission member 134 as shown in Figure 2The structure is shown in engagement connection, and the first driving wheel 132 and the first driven wheel 133 tighten the transmission belt, so that the first driving member 131 drives the first driving wheel 132 to rotate, drives the first driven wheel 133 and the first flexible transmission member 134 to operate, and drives the powder spreading roller 122 to rotate. The rotating direction of the powder spreading roller 122 changes with the operating direction of the first driving member 131, and the advancing direction of the powder spreading roller 122 relative to the printing material plane is consistent with the moving direction of the powder spreading device 120.

[0067] When the first driving device 130 is directly arranged on the cantilever 121 to drive the powder spreading roller 122, the cantilever 121 needs to reserve a large space for the installation of the motor and other components, causing the cantilever 121 to become long and the stiffness of the cantilever 121 to become poor. At the same time, the motor and other components increase the overall weight of the powder spreading device 120, increase the operating energy consumption of the powder spreading device 120 relative to the powder spreading platform 110, and the size of the driving motor of the powder spreading roller 122 is limited by the diameter of the powder spreading roller 122. A small motor is not enough to drive the powder spreading roller 122 to operate at high speed, and increasing the size of the motor needs to increase the diameter of the powder spreading roller 122, which causes the powder spreading device 120 to occupy a large height space. In addition, the direct connection of the motor to the powder spreading roller 122 causes the cantilever 121 to vibrate, affecting the powder spreading effect. Therefore, arranging the first driving device 130 on the powder spreading platform 110 reduces the occupied space and weight of the powder spreading device 120, reduces the structural cost and operating energy consumption, and improves the stability of powder spreading.

[0068] According to some embodiments of the present application, optionally, please refer to Figure 3a and Figure 3b , Figure 3a a perspective structure of the powder spreading roller 122 is shown, Figure 3b a structure of the powder spreading device is shown, the cantilever 121 is provided with a bearing seat 1211, the bearing seat 1211 is provided with a bearing 1233, one end of the powder spreading roller 122 is provided with a transmission shaft 1221, the transmission shaft 1221 is rotatably connected to the bearing seat 1211; the transmission shaft 1221 is provided with a first transmission wheel 1222, and the first transmission wheel 1222 is engaged with the first flexible transmission member 134.

[0069] As Figure 3b shown, the bearing seat 1211 is provided with a bearing 1233, the powder spreading roller 122 rotates on the bearing 1233 of the bearing seat 1211 through the transmission shaft 1221, the diameter of the transmission shaft 1221 is consistent with the hole diameter of the bearing, one end of the transmission shaft 1221 is connected with the first transmission wheel 1222, and the other end is connected with the powder spreading roller 122. The first transmission wheel 1222 is a gear shape and is engaged with the first flexible transmission member 134.

[0070] The first flexible transmission component 134 moves to drive the first transmission wheel 1222 to rotate, thereby driving the powder spreading roller 122 to rotate. The powder spreading roller 122 is restricted to rotate on the bearing seat 1211 by the transmission shaft 1221 and the bearing, which reduces the vibration of the powder spreading roller 122 caused by the first flexible transmission component 134 during the transmission process, making the powder spreading more stable.

[0071] Optionally, according to some embodiments of this application, please refer to Figure 4 , Figure 4 A schematic diagram of the installation structure of the tension wheel 1223 is shown. The first transmission wheel 1222 meshes with the inner side of the first flexible transmission member 134. The tension wheel 1223 is also rotatably mounted on the bearing seat 1211. The tension wheel 1223 is located on the outer side of the first transmission wheel and presses against the outer side of the first flexible transmission member 134.

[0072] like Figure 4 As shown, the tensioning wheel 1223 and the first transmission wheel 1222 are arranged on the same vertical plane. The first flexible transmission member 134 passes between the tensioning wheel 1223 and the first transmission wheel 1222. The tensioning wheel 1223 contacts the outer side of the first flexible transmission member 134, and the first transmission wheel 1222 meshes with the inner side of the first flexible transmission member 134.

[0073] The tensioning wheel 1223 presses the first flexible transmission member 134 inward, increasing the contact area between the inner side of the first flexible transmission member 134 and the first transmission wheel 1222. This increases the number of teeth meshing between the first transmission wheel 1222 and the inner side of the first flexible transmission member 134, and also further tightens the first flexible transmission member 134, improving transmission stability. Furthermore, because the tensioning wheel 1223 presses the outer side of the first flexible transmission member 134, the tensioning wheel 1223 rotates with the operation of the first flexible transmission member 134. The tensioning wheel 1223 can be mounted on the powder spreading device 120 via bearings, reducing rotational friction during rotation and lowering transmission losses.

[0074] Optionally, according to some embodiments of this application, please refer to Figure 4 There are two tensioning wheels 1223, which are located on both sides of the first transmission wheel 1222 along the preset moving direction.

[0075] During the powder spreading process, the powder spreading device 120 is positioned relative to the powder spreading platform 110 along... Figure 1The middle arrow A direction and the reverse direction of A do reciprocating motion, in order to ensure that the powder laying device 120 moves along the reciprocating two directions relative to the powder laying platform 110, the stability of the first flexible transmission member 134 driving the powder laying roller 122 to rotate, the number of the tensioning wheel 1223 is set to two and is respectively installed on both sides of the first transmission wheel 1222, and the meshing positions of the first flexible transmission member 134 and the two sides of the first transmission wheel 1222 are at a certain angle.

[0076] The two tensioning wheels 1223 make the first flexible transmission member 134 along Figure 1 When the middle A direction and the reverse direction of A operate, the acting force of the first flexible transmission member 134 driving the first transmission wheel 1222 is increased, which improves the stability of transmission and the service life of the first flexible transmission member 134.

[0077] According to some embodiments of the present application, optionally, please refer to Figure 3b The powder laying device 120 comprises a first bearing seat 1231 and a second bearing seat 1232, the first bearing seat 1231 and the second bearing seat 1232 are fixedly arranged below the cantilever 121, please refer to Figure 3a The first bearing seat 1231 and the second bearing seat 1232 are respectively provided with a bearing 1233, the hole positions of the bearings 1233 are consistent in height, and the powder laying roller 122 is rotationally connected between the bearings 1233 of the first bearing seat 1231 and the second bearing seat 1232.

[0078] The two ends of the powder laying roller 122 are respectively connected with the bearings 1233, the connection of the two ends of the powder laying roller 122 reduces the vibration generated when the powder laying roller 122 rotates, and improves the stability of the powder laying roller 122, the consistent height of the hole positions of the bearings 1233 makes the powder laying roller 122 parallel to the powder laying platform 110, and the printing material is pressed into a plane. Further, the first bearing seat 1231 and the second bearing seat 1232 can be respectively provided with a bearing cover for restraining the bearing 1233 to avoid the falling of the bearing 1233.

[0079] According to some embodiments of the present application, optionally, please refer to Figure 1 The second driving device 140 comprises a second driving member 141, a second driving wheel 142, a second driven wheel 143 and a second flexible transmission member 144; the second driving wheel 142 and the second driven wheel 143 are both rotationally arranged on the powder laying platform 110, and the second driving wheel 142 and the second driven wheel 143 are spaced apart along a preset moving direction, the second flexible transmission member 144 is sleeved between the second driving wheel 142 and the second driven wheel 143, the output shaft of the second driving member 141 is connected with the second driving wheel 142, and the second driving member 141 is used for moving the second flexible transmission member 144 through the second driving wheel 142; the cantilever 121 is fixedly connected with the second flexible transmission member 144, so that the cantilever 121 moves with the second flexible transmission member 144.

[0080] The second driving member 141 can be a motor fixedly arranged on the powder laying platform 110, and an output shaft of the motor is fixedly connected with the second driving wheel 142. The second driving device 140 can adopt the same mechanism as the first driving device 130 mentioned above, and details are not described herein again. The second driving member 141 drives the second flexible transmission member 144 to move in a preset direction and drives the cantilever 121 to move. When the powder laying device 120 moves to either end point of the second flexible transmission member 144, the second driving member 141 changes the rotating direction so that the second flexible transmission member 144 moves back and forth relative to the powder laying platform 110.

[0081] The second driving wheel 142 and the second driven wheel 143 are arranged at intervals, and the second flexible transmission member 144 is sleeved between the second driving wheel 142 and the second driven wheel 143, so that the second flexible transmission member 144 forms a moving path for the translation of the cantilever 121 relative to the powder laying platform 110. The length of the moving path is the interval distance between the second driving wheel 142 and the second driven wheel. By arranging the second driving wheel 142, the second driven wheel 143 and the second flexible transmission member 144 to form a transmission structure, the second driving member 141 can drive the second flexible transmission member 144 to drive the cantilever 121 to move along a fixed path relative to the powder laying platform 110, which is simple in structure and convenient to install.

[0082] According to some embodiments of the present application, optionally, please refer to Figure 5 The powder laying platform 110 is provided with a guide rail 111 in a preset moving direction, and the cantilever 121 is provided with a sliding block 112 which is slidingly connected to the guide rail 111.

[0083] Since the flexible transmission member will inevitably vibrate, the powder laying effect will be affected. As shown in Figure 5 The guide rail 111 is arranged in the preset moving direction, and the guide rail 111 can be arranged near the first flexible transmission member 134. The sliding block 112 slidingly arranged on the guide rail 111 can limit the moving track of the powder laying device 120 relative to the powder laying platform 110 to be a straight line.

[0084] The powder laying device 120 moves on the guide rail 111 through the sliding block 112, which can reduce the interference of the vibration of the flexible transmission member on the powder laying effect, so that the powder laying is more stable. Further, the guide rail 111 can also be arranged near the second flexible transmission member 144, and the sliding block 112 can be additionally arranged at the corresponding position of the powder laying device 120, and details are not described herein again. The guide rail 111 and the sliding block 112 should not be in direct contact with the flexible transmission member to avoid affecting the stability of the transmission.

[0085] In another aspect, the embodiment of the present application provides a powder laying control method, which is applied to the powder laying device 100 in any of the above embodiments and can be executed by a controller in the powder laying device or a controller in the 3D printer. Please refer to Figure 6 , Figure 6 The steps of the powder laying control method are shown in the figure. The method comprises the following steps:

[0086] S100: Obtain a preset moving speed and a preset rotating speed.

[0087] In this step, the preset moving speed and the preset rotating speed, which are the translational speed of the powder laying roller 122 and the rotating speed of the powder laying roller 122 obtained according to the motion trajectory equation of the powder laying roller 122 in the above scheme, are input into the controller.

[0088] S200: Calculate the output rotating speed of the second driving device 140 according to the transmission ratio between the second driving device 140 and the powder laying device 120 and the preset moving speed.

[0089] S300: Calculate the output rotating speed of the first driving device 130 according to the transmission ratio between the first driving device 130 and the powder laying roller 122 and the preset rotating speed.

[0090] In this step, according to the above scheme, the rotating speed of the second driving member 141 is n1, the pitch of the second driving wheel 142 driven by the second driving member 141 is a1, and the number of teeth is Z1; the rotating speed of the first driving member 131 is n2, the pitch of the first driving wheel 132 is a2, and the number of teeth is Z2; the pitch of the first transmission wheel 1222 is a2, the number of teeth is Z3, and the rotating speed of the first transmission wheel 1222 and the powder laying roller is equal to n3. The following conversion can be made:

[0091]

[0092] a1, a2, Z1, and Z3 are constant values, and the rotating speed of the first driving member 131 and the rotating speed of the second driving member 141 can be set by a motion controller. Therefore, the rotating speed of the powder laying roller 122 can be adjusted by adjusting the rotating speeds of the two motors. In actual application, only the translational speed of the powder laying device 120 and the rotating speed of the powder laying roller 122 are effective process parameters. Here, the moving speed of the powder laying device 120 is V, and V = n1a1Z1 / 60. The input parameters V and n3 are V and n3, and the controller converts them according to the conversion relationship

[0093]

[0094] to obtain the rotating speed n1 of the second driving member 141, and converts them according to the conversion relationship

[0095]

[0096] The rotational speed n2 of the first driving component 131 is obtained.

[0097] S400: Control the second drive device 140 to operate in the first rotation direction to drive the cantilever 121 to move along the first direction in the preset movement direction, and at the same time control the first drive device 130 to operate in the second rotation direction to drive the powder spreading roller 122 to rotate in the first direction in the preset rotation direction until the cantilever 121 moves to the first target position. When the powder spreading roller 122 rotates in the first direction, its linear velocity direction toward the bottom edge of the powder spreading platform 110 is the same as the first direction.

[0098] In this step, such as Figure 1 As shown, when the cantilever 121 moves in the direction of arrow A, the first rotation direction of the second drive member 141 is the direction indicated by arrow B. When n2 is positive, the second rotation direction of the first drive member is the direction indicated by arrow B; when n2 is negative, the second rotation direction of the first drive member 131 is the direction indicated by clockwise arrow C. The first direction of rotation of the powder spreading roller 122 is the direction indicated by arrow B. The first target position can be the endpoint of the movement trajectory in the direction of arrow A. Specifically, the first position can be obtained by setting a position sensor at the endpoint of the movement trajectory in the direction of arrow A. When the cantilever 121 moves to this endpoint, the position sensor sends a reversal signal to the controller. Alternatively, the distance that the cantilever 121 moves in the direction of arrow A can be recorded. When the distance reaches a preset value, a reversal signal is sent to the controller.

[0099] S500: Control the second drive device 140 to operate in the third rotation direction to drive the cantilever 121 to move along the second direction in the preset movement direction. At the same time, control the first drive device 130 to operate in the fourth rotation direction to drive the powder spreading roller 122 to rotate in the second direction in the preset rotation direction until the cantilever 121 moves to the second target position. When the powder spreading roller 122 rotates in the second direction, its linear velocity direction toward the bottom edge of the powder spreading platform 110 is the same as the second direction. The third rotation direction is opposite to the first rotation direction, the second direction is opposite to the first direction, the fourth rotation direction is opposite to the second rotation direction, and the second direction is opposite to the first direction.

[0100] In this step, when the cantilever 121 moves in the opposite direction of the second direction (arrow A), the third rotation direction of the second drive member 141 is the direction shown by arrow C, and at the same time, the fourth rotation direction of the first drive member 131 is the direction shown by arrow B. The second rotation direction of the powder spreading roller 122 is the direction shown by arrow B. The second target position can be the endpoint of the trajectory in the opposite direction of A. The specific method for obtaining the second position is the same as in step S500, and will not be elaborated further here.

[0101] S600: Jump to control the second driving device 140 to run in the first rotation direction to drive the cantilever 121 to move in the first direction of the preset moving direction, and control the first driving device 130 to run in the second rotation direction to drive the powder roller 122 to rotate in the first direction of the preset rotation direction, until the cantilever 121 moves to the first target position, until the powdering is completed.

[0102] The powdering control method provided by the embodiments of the present application drives the cantilever 121 to move back and forth relative to the powdering platform 110 through the second driving member 141, and simultaneously drives the powder roller 122 to rotate relative to the powdering platform 110 according to the moving direction of the cantilever 121 through the first driving member 131, which externally applies the self-rotation force of the powder roller 122, so that the rotation speed of the powder roller 122 is not limited by the moving speed of the powdering device 120, and the powdering wrinkles or powder raising caused by the limited rotation speed of the powder roller 122 in the powdering process is reduced, so that the printing material is compacted in the powdering process, and a good powdering effect is achieved. The preset moving speed and the preset rotation speed can be calculated through the mathematical relationship between the translation speed and the rotation speed of the powder roller 122, so that the powder roller can adjust the preset moving speed and the preset rotation speed according to different application scenarios, such as different types of printing materials, to ensure a good powdering effect.

[0103] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and the description of the present application. Especially, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A powder spreading apparatus, characterized by, The powder laying device comprises a powder laying platform, a powder laying device, a first driving device and a second driving device; The powder laying platform is used for laying printing materials; The powder laying device comprises a cantilever and a powder laying roller, the cantilever is slidingly arranged on the powder laying platform along a preset moving direction, and the powder laying roller is rotationally connected to the cantilever; The second driving device is arranged on the powder laying platform, the second driving device is connected with the cantilever, and the second driving device is used for driving the cantilever to move relative to the powder laying platform along the preset moving direction at a preset moving speed, so that the cantilever drives the powder laying roller to smooth the printing materials on the powder laying platform; The first driving device is connected with the powder laying roller, the first driving device is used for driving the powder laying roller to rotate relative to the powder laying platform at a preset rotating speed in a preset rotating direction, so that the powder laying roller compacts the printing materials on the powder laying platform, and when the powder laying roller rotates in the preset rotating direction, a linear velocity direction of the powder laying roller towards a bottom edge of the powder laying platform is the same as the preset moving direction; The first driving device comprises a first driving member, a first driving wheel, a first driven wheel and a first flexible transmission member; The first driving member is fixedly arranged on the powder laying platform; The first driving wheel and the first driven wheel are both rotationally arranged on the powder laying platform, and the first driving wheel and the first driven wheel are arranged in a spaced manner along the preset moving direction, the first flexible transmission member is sleeved between the first driving wheel and the first driven wheel, an output shaft of the first driving member is connected with the first driving wheel, and the first driving member is used for moving the first flexible transmission member through the first driving wheel; The powder laying roller is engaged with the first flexible transmission member, so that the powder laying roller rotates with the movement of the first flexible transmission member.

2. The powder spreading apparatus of claim 1, wherein The preset moving speed is positively correlated with the preset rotating speed.

3. The powder spreading apparatus of claim 1, wherein, A bearing seat is arranged on the cantilever, a bearing is arranged in the bearing seat, one end of the powder laying roller has a transmission shaft, and the transmission shaft is rotationally connected to the bearing seat through the bearing; A first transmission wheel is arranged on the transmission shaft, and the first transmission wheel is engaged with the first flexible transmission member.

4. The powder spreading apparatus of claim 3, wherein The first transmission wheel is engaged with the inner side surface of the first flexible transmission member, a tension wheel is also rotationally arranged on the bearing seat, the tension wheel is arranged on the outer side of the first transmission wheel, and the tension wheel is pressed against the outer side surface of the first flexible transmission member.

5. The powder spreading apparatus of claim 4, wherein, The number of the tension wheels is two, and the tension wheels are respectively located on the two sides of the first transmission wheel along the preset moving direction.

6. The powder spreading apparatus of any one of claims 1-4, wherein, The powder laying device comprises a first bearing seat and a second bearing seat, the first bearing seat and the second bearing seat are fixedly arranged below the cantilever, the first bearing seat and the second bearing seat are respectively provided with bearings, the heights of bearing holes are consistent, and the powder laying roller is rotationally connected between the bearings of the first bearing seat and the second bearing seat.

7. The powder spreading apparatus of any one of claims 1-4, wherein, The second driving device comprises a second driving member, a second driving wheel, a second driven wheel and a second flexible transmission member; The second driving wheel and the second driven wheel are rotatably arranged on the powder laying platform, and the second driving wheel and the second driven wheel are arranged at intervals along the preset moving direction, the second flexible transmission member is sleeved between the second driving wheel and the second driven wheel, and the output shaft of the second driving member is connected with the second driving wheel, so that the second driving member drives the second flexible transmission member to move through the second driving wheel. The cantilever is fixedly connected with the second flexible transmission member, so that the cantilever moves with the second flexible transmission member.

8. The powder spreading apparatus of any one of claims 1-4, wherein, The powder laying platform is provided with a guide rail along the preset moving direction, and the cantilever is provided with a sliding block which is slidingly connected with the guide rail.

9. A powder spreading control method characterized by, The method is applied to the powder laying device as claimed in any one of claims 1-8, and the method comprises: acquiring the preset moving speed and the preset rotating speed; calculating the output rotating speed of the second driving device according to the transmission ratio between the second driving device and the powder laying device and the preset moving speed; calculating the output rotating speed of the first driving device according to the transmission ratio between the first driving device and the powder laying roller and the preset rotating speed; controlling the second driving device to operate in a first rotating direction to drive the cantilever to move in a first direction in the preset moving direction, and controlling the first driving device to operate in a second rotating direction to drive the powder laying roller to rotate in a first direction in the preset rotating direction, until the cantilever moves to a first target position, wherein when the powder laying roller rotates in the first direction, the linear velocity direction of the powder laying roller towards the bottom edge of the powder laying platform is the same as the first direction; controlling the second driving device to operate in a third rotating direction to drive the cantilever to move in a second direction in the preset moving direction, and controlling the first driving device to operate in a fourth rotating direction to drive the powder laying roller to rotate in a second direction in the preset rotating direction, until the cantilever moves to a second target position, wherein when the powder laying roller rotates in the second direction, the linear velocity direction of the powder laying roller towards the bottom edge of the powder laying platform is the same as the second direction, the third rotating direction is opposite to the first rotating direction, the second direction is opposite to the first direction, and the second direction is opposite to the first direction; jumping to the control of the second driving device to operate in the first rotating direction to drive the cantilever to move in the first direction in the preset moving direction, and the control of the first driving device to operate in the second rotating direction to drive the powder laying roller to rotate in the first direction in the preset rotating direction, until the cantilever moves to the first target position, until the powder laying is completed. The second driving wheel and the second driven wheel are rotatably arranged on the powder laying platform, and the second driving wheel and the second driven wheel are arranged at intervals along the preset moving direction, the second flexible transmission member is sleeved between the second driving wheel and the second driven wheel, and the output shaft of the second driving member is connected with the second driving wheel, so that the second driving member drives the second flexible transmission member to move through the second driving wheel. The cantilever is fixedly connected with the second flexible transmission member, so that the cantilever moves with the second flexible transmission member. The powder laying platform is provided with a guide rail along the preset moving direction, and the cantilever is provided with a sliding block which is slidingly connected with the guide rail. The method is applied to the powder laying device as claimed in any one of claims 1-8, and the method comprises: acquiring the preset moving speed and the preset rotating speed; calculating the output rotating speed of the second driving device according to the transmission ratio between the second driving device and the powder laying device and the preset moving speed; calculating the output rotating speed of the first driving device according to the transmission ratio between the first driving device and the powder laying roller and the preset rotating speed; controlling the second driving device to operate in a first rotating direction to drive the cantilever to move in a first direction in the preset moving direction, and controlling the first driving device to operate in a second rotating direction to drive the powder laying roller to rotate in a first direction in the preset rotating direction, until the cantilever moves to a first target position, wherein when the powder laying roller rotates in the first direction, the linear velocity direction of the powder laying roller towards the bottom edge of the powder laying platform is the same as the first direction; controlling the second driving device to operate in a third rotating direction to drive the cantilever to move in a second direction in the preset moving direction, and controlling the first driving device to operate in a fourth rotating direction to drive the powder laying roller to rotate in a second direction in the preset rotating direction, until the cantilever moves to a second target position, wherein when the powder laying roller rotates in the second direction, the linear velocity direction of the powder laying roller towards the bottom edge of the powder laying platform is the same as the second direction, the third rotating direction is opposite to the first rotating direction, the second direction is opposite to the first direction, and the second direction is opposite to the first direction; jumping to the control of the second driving device to operate in the first rotating direction to drive the cantilever to move in the first direction in the preset moving direction, and the control of the first driving device to operate in the second rotating direction to drive the powder laying roller to rotate in the first direction in the preset rotating direction, until the cantilever moves to the first target position, until the powder laying is completed.

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