阅读说明：本技术 一种涂覆刮刀装置及具备该装置的3d打印设备 (Coating scraper device and 3D printing equipment with same ) 是由 赖永辉 马劲松 于清晓 马跃科 杨根 于 2021-02-08 设计创作，主要内容包括：本发明提供一种涂覆刮刀装置及具备该装置的3D打印设备,其用于在3D打印装置中涂覆3D打印材料,具备：工作台单元、刮刀单元和框架平台；工作台单元具备：工作台；成型缸；成型缸驱动机构；料缸；和料缸驱动机构；刮刀单元沿工作台上表面所在平面水平移动,具备：涂覆刮刀主体框架；刮刀单元驱动机构；分别沿上下方向移动规定距离的两个涂覆刮刀；离合凸轮机构；和离合凸轮驱动机构。根据本发明,通过设置两个涂覆刮刀,从而在涂覆刮刀装置在工作台上往复运动过程中均可实现打印,结构简单、涂覆均匀、工作效率高且材料利用率高。(The invention provides a coating scraper device and a 3D printing device with the same, which are used for coating a 3D printing material in a 3D printing device and are provided with: the device comprises a workbench unit, a scraper unit and a frame platform; the table unit includes: a work table; a forming cylinder; a forming cylinder drive mechanism; a material cylinder; and a material cylinder driving mechanism; the scraper unit moves horizontally along the plane of the upper surface of the workbench, and is provided with: coating the scraper body frame; a scraper unit drive mechanism; two coating blades moving a prescribed distance in the up-down direction, respectively; a clutch cam mechanism; and a clutch cam driving mechanism. According to the invention, by arranging the two coating scrapers, printing can be realized in the reciprocating process of the coating scraper device on the workbench, and the device has the advantages of simple structure, uniform coating, high working efficiency and high material utilization rate.)

1. A coating blade device for coating 3D printing material in a 3D printing device,

the disclosed device is provided with: the device comprises a workbench unit, a scraper unit and a frame platform;

the table unit includes:

a table for printing a workpiece;

the forming cylinder is concavely arranged on the workbench and internally provided with a workpiece to be formed;

a forming cylinder driving mechanism capable of moving the forming cylinder in an up-and-down direction perpendicular to a plane of the upper surface of the worktable by a predetermined distance;

the material cylinder is concavely arranged on the workbench, is arranged in parallel with the forming cylinder and is internally provided with printing materials; and

a material cylinder driving mechanism capable of moving the material cylinder in the up-down direction by a prescribed distance;

the scraper unit moves horizontally along the plane of the upper surface of the workbench, and comprises:

a coating blade main body frame which is installed on the workbench unit and can move along the parallel direction of the material cylinder and the forming cylinder;

a blade unit driving mechanism for driving the coating blade main body frame to horizontally move along the plane of the upper surface of the workbench;

two coating scrapers which are arranged in parallel in the coating scraper main body frame and move a specified distance in the up-down direction respectively;

the clutch cam mechanism is arranged on the coating scraper main body frame and is connected with the two coating scrapers; and

the clutch cam driving mechanism drives the clutch cam mechanism to rotate so as to drive the two coating scrapers to move up and down respectively.

2. The coating blade device according to claim 1,

the scraper unit further includes: the pre-spreading roll shaft is arranged in parallel with the two coating scrapers and is positioned between the two coating scrapers; and a pre-laying roller shaft driving mechanism for driving the pre-laying roller shaft to rotate and/or move for a specified distance along the up-down direction.

3. The coating blade device according to claim 1,

the upper surface of the workbench is convexly provided with a pair of guide rails for the scraper unit to move, and the pair of guide rails are provided with scraper grooves with the size corresponding to the width size of the coating scraper on the workbench in a manner of clamping the forming cylinder and the material cylinder.

4. The coating blade device according to claim 1,

the 3D printing material is ceramic paste, ceramic slurry, plastic powder, metal powder or wax powder.

5. The coating blade device according to claim 1,

the driving mechanism is a stepping motor or a driving motor.

6. The coating blade device according to claim 1,

the forming cylinder and the material cylinder have the same size.

7. 3D printing device provided with a coating blade arrangement according to any of the claims 1 to 6.

Technical Field

The invention relates to a coating blade device and a 3D printing device with the same.

Background

3D printing is a rapid prototyping technique that builds objects by layer-by-layer printing using bondable materials such as powdered metals, plastics, and resins based on digital model files. The 3D printing apparatus manufactures a 3D object by performing such a printing technique. The 3D printing equipment has wide application in the fields of dies, customized commodities, medical jigs, prostheses and the like due to high forming precision. The current popular 3D printing technology categories mainly include SLA/DLP technology, FDM fused deposition modeling technology, 3DP technology, SLS selective laser sintering, etc.

Among them, 3D printing materials are rapidly developed in recent years as a new technology industry, and become a national focus-driven development industry. The 3D printing materials are different in types according to different 3D printing molding technologies, at present, the total amount of the 3D printing materials is more than 200, and the materials come out at intervals, and in recent years, plastic materials, ceramic materials, metal materials, wood materials, wax materials and the like are successively introduced as the 3D printing materials.

The coating scraper for coating 3D printing materials such as metal powder, ceramic materials and the like on the market generally adopts a single scraper structure, has the advantages of simple structure, low cost and the like, and also has the defect of not being neglected. Particularly, when 3D printing apparatus design for a more common shaping jar with a material jar structure side by side, single scraper can only one-wayly coat 3D printing material, promptly, with the material in the material jar one-wayly scrape into the shaping jar in, can only print the one deck once scraping, the scraper need get back to the material jar position when printing next layer. In addition, one-way scraper can not scrape the material return jar with the unnecessary 3D printing material of last layer, and is not only inefficient, still can not make full use of raw and other materials, prints the same high part and needs more raw and other materials.

Disclosure of Invention

The problems to be solved by the invention are as follows:

in view of the above problems, an object of the present invention is to provide a coating blade device with simple structure, uniform coating, high work efficiency and high material utilization rate, and a 3D printing apparatus having the same.

The technical means for solving the problems are as follows:

the present invention provides a coating blade device for coating a 3D printing material in a 3D printing device, comprising: the device comprises a workbench unit, a scraper unit and a frame platform;

the table unit includes:

a table for printing a workpiece; the forming cylinder is concavely arranged on the workbench and internally provided with a workpiece to be formed; a forming cylinder driving mechanism capable of moving the forming cylinder in an up-and-down direction perpendicular to a plane of the upper surface of the worktable by a predetermined distance; the material cylinder is concavely arranged on the workbench, is arranged in parallel with the forming cylinder and is internally provided with printing materials; and a material cylinder driving mechanism capable of moving the material cylinder in the up-down direction by a prescribed distance;

the scraper unit moves horizontally along the plane of the upper surface of the workbench, and comprises:

a coating blade main body frame which is installed on the workbench unit and can move along the parallel direction of the material cylinder and the forming cylinder; a blade unit driving mechanism for driving the coating blade main body frame to horizontally move along the plane of the upper surface of the workbench; two coating scrapers which are arranged in parallel in the coating scraper main body frame and move a specified distance in the up-down direction respectively; the clutch cam mechanism is arranged on the coating scraper main body frame and is connected with the two coating scrapers; and the clutch cam driving mechanism drives the clutch cam mechanism to rotate so as to drive the two coating scrapers to move along the up-down direction respectively.

According to the invention, the two coating scrapers which can respectively move along the up-down direction are arranged, so that printing can be realized in the reciprocating process of the coating scraper device on the workbench, namely, the coating scraper device can realize double-layer printing once reciprocating relative to the workbench, namely, the coating scraper device can realize one-time coating of printing materials once moving in one direction on the workbench, and correspondingly, the coating of the printing materials is realized once again once moving back to the original position in reverse direction, thereby improving the printing efficiency.

Specifically, the scraper unit is located at the initial position and is closer to the material cylinder than the forming cylinder, the clutch cam driving mechanism drives the cam to rotate, one coating scraper which is relatively far away from the material cylinder in the two coating scrapers is lowered to be abutted against the upper surface of the workbench, the other coating scraper is lifted to be a specified height away from the upper surface of the workbench, meanwhile, the material cylinder driving mechanism drives the material cylinder to move upwards by a layer of printing layer thickness, raw materials (namely, printing materials) in the cylinder are extruded, and in order to ensure that the coating is uniform and has no omission, the extruded materials are necessarily more than the materials required by coating a layer of workpieces.

And then, the scraper unit moves along the upper surface of the workbench under the driving of the scraper unit driving mechanism, one coating scraper firstly scrapes the material cylinder to coat the printing material extruded from the material cylinder into the forming cylinder which passes through the scraper unit subsequently to realize the first layer printing, and because the material extruded from the material cylinder remains after the first layer printing, the clutch cam driving mechanism drives the cam of the clutch cam mechanism to rotate again, so that one coating scraper which is originally abutted against the upper surface of the workbench is lifted to a specified height from the upper surface of the workbench, and the other coating scraper is lowered to be abutted against the upper surface of the workbench, and meanwhile, when one layer is printed, the forming cylinder driving mechanism drives the forming cylinder to move downwards by a printing layer thickness.

Then, the doctor unit is moved in the reverse direction along the upper surface of the table, i.e., returned to the home position, by the drive of the doctor unit drive mechanism. In the moving process, the other side coating scraper is abutted with the upper surface of the workbench to scrape the residual material through the forming cylinder, so that the second layer printing is realized, then the residual printing material is pushed back to the material cylinder, so that the scraper unit completes one reciprocating motion, and the two-layer printing is realized.

In the present invention, the doctor unit may further include: the pre-spreading roll shaft is arranged in parallel with the two coating scrapers and is positioned between the two coating scrapers; and a pre-laying roller shaft driving mechanism for driving the pre-laying roller shaft to rotate and/or move for a specified distance along the up-down direction.

From this, can strike off the material of mixing in advance before the printing material through addding the roller of spreading in advance at the scraper, then will print the even coating of material in the shaping jar top through the coating scraper to improve the coating quality when individual layer coats at every turn, improve printing quality and success rate.

In the present invention, a pair of guide rails on which the doctor unit is moved may be provided so as to protrude from an upper surface of the table, and a doctor groove having a size corresponding to a width of the coating doctor may be formed on the table so as to sandwich the forming cylinder and the material cylinder.

Therefore, the material scraped out after the first coating of each scraper is in the scraper groove, almost all the remainders can be coated again along the scraper groove during the second reverse coating, the materials can be recycled as far as possible, the waste of the materials is avoided, and due to the fact that the materials can be almost completely utilized, the working cost can be reduced, and the equivalent filling from the material cylinder to the forming cylinder can be theoretically realized.

In the invention, the 3D printing material may be ceramic paste, ceramic slurry, plastic powder, metal powder or wax powder.

In the present invention, the driving mechanism may be a stepping motor or a driving motor.

In the present invention, the forming cylinder and the material cylinder may have the same size. Thus, the manufacturing cost can be further reduced and the structure can be made compact.

The invention also provides 3D printing equipment with the coating scraper device.

The invention has the following effects:

the invention aims to provide a coating scraper device which is simple in structure, uniform in coating, high in working efficiency and high in material utilization rate, and 3D printing equipment with the coating scraper device.

Drawings

Fig. 1 is a perspective view showing a coating blade device of the present invention;

FIG. 2 is a side view showing the coating blade assembly of the present invention;

FIG. 3 is a top view showing the coating blade apparatus of the present invention;

fig. 4 is a perspective view showing a part of the blade unit of the present invention;

fig. 5 is a sectional view showing a part of the blade unit viewed along a sectional line a-a shown in fig. 3;

fig. 6 is a partial perspective view showing a clutch cam mechanism-related structure of the blade unit of the present invention;

description of the symbols:

d-a coating blade device;

1-a table unit; 10-a workbench; 11-a forming cylinder; 12-forming cylinder drive mechanism; 13-material cylinder; 14-a material cylinder driving mechanism; 15-a guide rail;

2-a scraper unit; 21-coating the blade body frame; 22-a scraper unit drive mechanism; 23-a coating blade; 24-a clutch cam mechanism; 25-clutch cam driving mechanism; 26-pre-paving a roll shaft; 27-pre-paving roller shaft driving mechanism;

3-frame platform.

Detailed Description

The present invention is further described below in conjunction with the following embodiments, which are to be understood as merely illustrative, and not restrictive, of the invention. All other embodiments, which can be derived by a person skilled in the art from the examples without making any creative effort, shall fall within the protection scope of the present invention. The same or corresponding reference numerals denote the same components in the respective drawings, and redundant description is omitted.

Moreover, various mechanical terms are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In the present invention, for convenience of description, the moving direction of the table during printing is defined as the "up-down direction", and the directions or positional relationships indicated by the terms "left", "right", "front", "rear", and the like are based on the directions or positional relationships shown in the drawings, and it is not intended to indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and thus, it is not to be construed as limiting the present invention.

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Fig. 1 is a perspective view showing a coating blade device D of the present invention, fig. 2 is a side view showing the coating blade device D of the present invention, and fig. 3 is a plan view showing the coating blade device D of the present invention. As shown in fig. 1 to 3, disclosed herein is a coating blade device D for coating a 3D printing material in a 3D printing device, which is provided with a table unit 1, a blade unit 3, and a frame platform 3. The frame platform 3 is used for supporting the working table unit 1 and the scraper unit 2, and is not limited to a specific structure or form as long as the fixing and supporting functions can be achieved.

[ Table Unit ]

In the present invention, the table unit 1 includes a table 10, a forming cylinder 11, a forming cylinder driving mechanism 12, a material cylinder 13, a material cylinder driving mechanism 14, and a pair of guide rails 15. Specifically, the worktable 10 has a horizontal worktable upper surface for printing a 3D workpiece, on which a forming cylinder 11 for receiving a workpiece to be formed and a material cylinder 13 for receiving a 3D printing material are concavely mounted, respectively. The upper openings of the forming cylinder 11 and the material cylinder 13 are flush with the upper surface of the workbench, the lower sides of the forming cylinder 11 and the material cylinder 13 are respectively and correspondingly connected with a forming cylinder driving mechanism 12 and a material cylinder driving mechanism 14, and the forming cylinder 11 and the material cylinder 13 can move for a specified distance relative to the workbench 10 in the vertical direction vertical to the upper surface of the workbench under the driving of the driving mechanisms.

Further, the forming cylinder 11 and the material cylinder 13 are arranged side by side in the moving direction of the doctor unit 2, and particularly in the present invention, since the equal amount (i.e., 1: 1) of filling from the material cylinder 13 to the forming cylinder 11 can be realized, the forming cylinder 11 and the material cylinder 13 can have substantially the same shape and size. In addition, the forming cylinder 11 and the material cylinder 13 are formed into a structure with a variable internal storage space, and the pressing and expansion of the internal storage space can be realized by the forming cylinder driving mechanism 12 installed below the forming cylinder 11 and the material cylinder driving mechanism 14 installed below the material cylinder 13. For example, in the present invention, the forming cylinder 11 and the material cylinder 13 are formed into a structure similar to an injector, the size of the space (i.e., the storage space of the workpiece or the material) in the "cylinder" is changed by controlling the up-and-down movement of the "core bar" by the driving mechanism, and for example, the printing material in the material cylinder 13 can be extruded from the opening by pressing the space in the "cylinder" by the "core bar", and for example, the larger workpiece can be accommodated in the forming cylinder 11 by increasing the space in the "cylinder" by the "core bar", but the specific implementation manner is not limited to the above examples.

The pair of guide rails 15 are provided on the upper surface of the table so as to sandwich the two molding cylinders 11 and the material cylinder 13 arranged in parallel, and guide the doctor unit 2 to move along a predetermined trajectory. The guide rails 15 are formed in a structure protruding upward from the upper surface of the table so as to form blade grooves with a size corresponding to that of a coating blade described later with respect to each other. Therefore, the printing material coated at each time can not cross the guide rail 15 protruding out of the surface of the workbench to diffuse all around, but is separated and blocked in the scraper groove between the two guide rails, so that the material can be fully utilized, and the subsequent complex cleaning work can be avoided.

[ doctor unit ]

In the present invention, the entire blade unit 2 is horizontally movable along the plane of the upper surface of the table, and includes a coating blade main body frame 21, a blade unit driving mechanism 22, a coating blade 23, a clutch cam mechanism 24, a clutch cam driving mechanism 25, a pre-laying roller shaft 26, and a pre-laying roller shaft driving mechanism 27. Fig. 4 is a perspective view showing a part of the blade unit 2 of the present invention, fig. 5 is a sectional view showing a part of the blade unit 2 viewed along a sectional line a-a shown in fig. 3, and fig. 6 is a partial perspective view showing a structure relating to the clutch cam mechanism 24 of the blade unit 2 of the present invention.

As shown in fig. 4 to 6, the coating blade main body frame 21 is mounted on the table 10, and is mainly composed of parallel clamp plates 211 on both sides and a plurality of rod members 212 disposed between the clamp plates 211. The plurality of rod members 212 are disposed in parallel between the two clamping plates 211 to mainly support and fix the same, and theoretically, the number, size, installation manner, and the like are not limited as long as the structure is stable and does not interfere with other structures, but actually, as shown in the present invention, it is preferable that four rod members 212 are symmetrically fixed to the corners. The coating blade body frame 21 is further mounted on the frame platform 3 for stabilizing the overall structure of the apparatus, i.e., the width of the coating blade device D is limited by the both side clamping plates 211 in the present invention, in order to achieve the stable mounting of the entire apparatus on the frame platform 3 by one mechanical structure, but in practice, it is not necessary to form the structure for clamping the frame platform 3 at all, for example, one mechanical structure may be used to mount the blade unit 2 on the table unit 1 in a relatively movable manner, and another mechanical structure may be used to mount the blade unit 2 and the table unit 1 on the frame platform 3 in a stable manner, and the structural stability of the coating blade device D is achieved by two mechanical structures. The mechanical structure is not limited to the engagement, engagement locking, welding, and fixing of the gears.

As shown in fig. 3, the doctor unit driving mechanism 22 is attached to the frame platform 3, and is connected to the coating doctor main body frame 21 via a driving belt 221 shown in fig. 2 to be driven to move in the horizontal direction as shown in the drawing, that is, in the parallel direction of the material cylinder 13 and the forming cylinder 11. The mounting position of the blade unit driving mechanism 22 is not particularly limited, and the driving manner is not limited to the driving belt and may be adjusted according to the actual situation. Hereinafter, for the sake of simplicity of explanation, the coating blade main body frame 21 and its internal structure are generically referred to as the blade unit 2 without separately emphasizing the blade unit driving mechanism 22.

Two coating blades 23 of identical construction are also arranged offset and parallel between the two clamping plates 211, i.e. the coating blades 23 and the bar members 212 are also parallel to one another. Two clutch cam mechanisms 24 are respectively mounted on the inner side surfaces between the both side clamping plates 211, both ends of the two coating scrapers 23 are respectively connected to the clutch cam mechanisms 24, and a clutch cam driving mechanism 25 is mounted on the outer side surface of either side clamping plate 211 and is provided with a clutch main shaft 251 disposed between the both side clamping plates 211. The two clutch cam mechanisms 24 are connected to both ends of the clutch main shaft 251, respectively, so that the clutch main shaft 251 is driven by the clutch cam driving mechanism 25 to rotate by a predetermined angle, thereby driving the two coating blades 23 to move in the up-down direction, respectively.

Specifically, as shown in fig. 6, both ends of the both-side coating blade 23 are respectively connected with two elastic members 245, which are springs, for example, for a total of four elastic members. The elastic member 245 is fixed at one end, and is capable of moving the coating blade 23 in an elastic direction (up-down direction in this embodiment) within an elastic range by elastic deformation of the elastic member under an external force. The clutch cam mechanism 24 includes followers 247 and cams 244 connected to the two coating blades 23 and the elastic member 245, respectively, that is, the clutch cam mechanisms 24 on both sides have four followers 247 and cams 244 in total, one end of the follower 247 is in relatively movable contact with the cam 244, the other end is connected to the coating blade 23 or the elastic member 245, the protruding portions of the two cams 244 on the same side should be reversed to ensure that the two blades connected to each other can move up and down, and the protruding portions of the two cams 244 connected to both ends of the same coating blade 23 should be in the same direction to ensure that both ends of the blades are synchronized.

When the clutch cam driving mechanism 25 drives the cam 244 of the clutch cam mechanism 24 to rotate through the clutch main shaft 251, the cam 244 makes the driven member 247 move up and down according to rules due to the shape characteristics when rotating, so as to apply external force to the elastic member 245, because the protruding parts on the same side are installed oppositely, one elastic member 245 on the side is stressed with small pressure and relatively extends, the coating scraper 23 is pushed to move down, and the other elastic member 245 is stressed with large pressure and relatively shortens, so as to drive the coating scraper 23 to move up and down, thereby realizing the up and down movement of the coating scraper 23. The coating blade 23 is provided with clutch cam mechanisms 24 at both ends (both sides) thereof, and is driven synchronously by a clutch main shaft 251, thereby achieving stable up-and-down movement. In the present embodiment, fig. 6 shows a mechanical structure in which the scraper is moved up and down by the rotation of the cam, but the invention is not limited thereto, and there is no technical obstacle for those skilled in the art to realize the up and down movement of the scraper by means of the rotation of the gear set.

Further, the pre-coat roller shaft 26 is provided between the two nip plates 211 and between the two coating blades 23, and is formed in a parallel configuration with the rod member 212 and the like. The pre-laying roller shaft drive 27 is installed on the outer side surface of the side clamping plate 211, is electrically connected with the pre-laying roller shaft 26, and is used for driving the pre-laying roller shaft 26 to rotate and/or move for a specified distance along the vertical direction. For example, the actual height of the pre-spreading roller shaft 26 may be adjusted according to the amount of the printing material, etc. to achieve the uniform mixing degree and the uniform spreading state of the rolled printing material, and the pre-spreading roller shaft 26 may be increased according to the actual requirement so as not to participate in the rolling operation at all. The material can be mixed uniformly in advance before the printing material is strickleed off by the coating scraper 23 by adding the pre-paving roller shaft 26, and then the printing material is uniformly coated above the forming cylinder 11 by the coating scraper 23, so that the coating quality during each single-layer coating is improved, and the printing quality and the success rate are improved. In the present invention, the pre-placement roller shaft drive 27 and the clutch cam drive mechanism 25 are mounted on the same side so as to be vertically overlapped with each other, but the present invention is not limited thereto. In addition, the pre-coat roller shaft 26 and the coating blade 23 may be controlled by separate driving motors, respectively.

< example >

The present invention will be described in detail by way of examples. It is also to be understood that the following examples are intended only to further illustrate the particular manner in which the present invention operates.

As shown in fig. 1 to 3, a position of the scraper unit 2 on the side close to the material cylinder 13 is defined as a start position, and at this time, the blade unit 2 is closer to the material cylinder 13 than the forming cylinder 11, the clutch cam driving mechanism 25 drives the clutch cam mechanism 24 to rotate, so that one coating blade 23 (the right side in fig. 3) of the two coating blades 23 relatively far from the material cylinder 13 is lowered to be in contact with the upper surface of the table, the other coating blade 23 (the left side in fig. 3) is raised to a predetermined height from the upper surface of the table, meanwhile, the material cylinder driving mechanism 14 drives the material cylinder 13 to move upwards by the specified height, and the 3D printing material in the cylinder is extruded, so that the coating is uniform and is not missed, and the extruded printing material is more than the material consumption required by coating a layer of workpiece.

Next, the doctor unit 2 is driven by the doctor unit driving mechanism 22 to move in the left-right direction shown in fig. 3 along the upper surface of the table, and the pre-spreading roller shaft 26 is located between the two coating scrapers 23, so that the printing material extruded from the material cylinder 13 is contacted earlier than the coating scraper 23 abutting against the upper surface of the table, and after the uniform mixing, the coating scraper 23 on the right side passes through the material cylinder 13 first, and the printing material scraped therefrom is uniformly applied to the workpiece to be printed in the forming cylinder 11 that passes through next, thereby realizing the first layer printing, but the printing material extruded from the material cylinder 13 remains after the first layer printing.

At this time, the doctor unit 2 is stopped at a position on the side close to the forming cylinder 11, that is, the doctor unit 2 is closer to the forming cylinder 11 than to the material cylinder 13. The clutch cam driving mechanism 25 drives the clutch cam mechanism 24 to rotate, so that one of the two coating blades 23 (the right side in fig. 3) that originally comes into contact with the upper surface of the table is raised to a predetermined height from the upper surface of the table, and the other coating blade 23 (the left side in fig. 3) is lowered to come into contact with the upper surface of the table, which can be understood as interchanging the relative vertical relationship of the two coating blades 23.

Next, the blade unit 2 is moved in the reverse direction along the upper surface of the table, i.e., returned to the start position, by the driving of the blade unit driving mechanism 22. In the moving process, the other side coating scraper 23 is abutted against the upper surface of the workbench to scrape the residual material to coat the residual material on the workpiece to be printed in the forming cylinder 11, so that the second layer printing is realized, and then most of the possible residual printing material is pushed back to the material cylinder 13, so that the scraper unit 2 completes one reciprocating motion, and the two-layer 3D printing is realized.

Whenever printing is completed one layer, the forming cylinder driving mechanism 12 drives the forming cylinder 11 to move down by one layer of the printing layer thickness regardless of the forward stroke of the doctor unit 2 from the home position or the backward stroke of returning to the home position, and waits for the next printing. And the cylinder drive mechanism 14 drives the cylinder 13 to move up to extrude the printing material when the doctor unit 2 goes out, and moves down to accommodate the remaining printing material pushed back when the doctor unit 2 goes back.

Therefore, the high utilization rate of printing materials can be achieved, and due to the fact that the reciprocating motion of the scraper is effective coating, the materials are fully utilized, and therefore the working efficiency of the 3D printing equipment can be greatly improved.

In addition, at each time of reciprocating, the coating scraper 23 at one side relatively far away from the cylinder body is in contact with the upper surface of the workbench, the coating scraper 23 at the other side is lifted, redundant materials scraped after the printing materials are coated for the first time are blocked in the scraper groove by the guide rails 15 at two sides, after the other end of the scraper unit 2 moves, the coating scraper 23 at the other side relatively far away from the cylinder body is in contact with the upper surface of the workbench, the coating scraper 23 at one side working slightly ahead is lifted, and when the printing materials are coated reversely for the second time, almost all the residual materials in the scraper groove can be pushed back to the material cylinder 13 after being coated again. Both coating passes are performed by the more distant one of the two coating blades 23, so that no material remains between the blades. The guide rails 15 are raised to form a blade groove matching the width of the coating blade 23, and the material in the groove can be scraped off each time. The pre-spreading roller shaft 26 presses the printing material before the coating scraper 23 coats the printing material, so that the printing material is uniformly mixed and spread as much as possible, and the subsequent coating scraper 23 can coat the printing material efficiently. In this way, the material can be recovered as much as possible, waste of the material can be avoided, and since the material can be almost completely used, the working cost can be reduced, and theoretically, the equivalent filling from the material cylinder 13 to the molding cylinder 11 can be realized.

In the present invention, all the driving mechanisms are not particularly limited as long as the corresponding functions can be achieved, and may be, for example, a stepping motor or a driving motor. The present invention is widely applicable to industrial use, and the 3D printing material to which the present invention is applied may be, for example, a powdery material such as a ceramic paste, a ceramic slurry, a plastic powder, a metal powder, or a wax powder. The pair of guide rails 15 and the scraper grooves formed therein may be recessed downward from the upper surface of the table, and substantially the same effect as the scraper grooves formed by the pair of guide rails 15 protruding upward can be obtained. The frame platform 3 can be formed in various sizes in accordance with peripheral equipment, and it is sufficient if it can support and fix the coating blade 23 device D thereon, and this configuration can maximize the matching with various installation places and the adaptation to the peripheral environment without changing the coating blade 23 device D, thereby enhancing the device compatibility at a minimum cost. In the present invention, the cylinder driving mechanism 14 may drive the cylinder 13 to move up to a height of two printing layers according to the properties of the printing material, and the like, and the printing material having a rigid amount may be extruded for coating twice, and in this case, the cylinder 13 may not be lowered during the return stroke of the doctor unit 2. In the present invention, the shape of the doctor blade, the shape of the roller shaft, and the like are not particularly limited, and the doctor blade may be formed in a multi-blade assembly structure as shown in the drawings, but may be formed in another structure that achieves a similar function, such as a structure in which the doctor blade is integrally formed in a single piece.

In conclusion, the coating scraper device D provided by the invention has the advantages of simple structure, uniform coating, high working efficiency, high material utilization rate and wide application range, and is beneficial to industrial production.

The above embodiments are intended to illustrate and not to limit the scope of the invention, which is defined by the claims, but rather by the claims, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.