Powder spreading mechanism and 3D printer

Abstract

The present invention relates to a powder spreading mechanism and a 3D printer. The 3D printer includes the powder spreading mechanism. The powder spreading mechanism includes: a mounting frame, a powder discharging component, a vibration component and a scraping component; the powder discharging component includes a powder bin, a vibration side plate and an adjustment side plate arranged on the mounting frame, the vibration side plate and the adjustment side plate are arranged on the periphery of the powder outlet of the powder bin, and an adjustable drop opening is formed between the vibration side plate and the adjustment side plate; the vibration component includes a vibration main body and a vibration driving member drivingly connected to the vibration main body, the vibration main body is mounted on the mounting frame and connected to the vibration side plate; the scraping component includes a support seat and a scraper, the support seat is mounted on the mounting frame, and the scraper is mounted on one side of the support seat close to the drop opening, and is used to scrape the powder spreading surface. The powder spreading mechanism and the 3D printer can stably adjust the amount of powder discharging, and have high working efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of 3D printing, and in particular to a powder spreading mechanism and a 3D printer. Background Art

[0002] The existing 3DP printing technology is mainly based on additive manufacturing, which constructs complex parts by printing, sintering, melting and bonding powder solids of different materials in layers. The usual process is: data slicing processing → work box descends → powder spreader spreads powder → print head prints slice image → work box descends again → powder spreader spreads powder again → print head prints slice image again, and prints in sequence. In the whole working process, the powder spreader is an important forming structure. It runs continuously to spread hundreds or thousands of layers of powder in the whole forming process. In such an important process, to ensure the accuracy, levelness and uniformity of each layer, the powder spreading equipment needs to run stably and efficiently, and there will be no problems of no powder, pushing powder and pulling powder. The one-way powder spreading mechanism in the prior art adopts an integrated structure, and specifically adopts an integrated design for the powder spreading structure and the scraping structure, which causes slight changes in the scraping structure when adjusting the amount of powder. As for the two-way powder spreading mechanism, although its working efficiency is high, it is complicated in structure, high in equipment cost, and difficult to adjust and restore after a slight structural change, resulting in its low reliability, and thus failing to achieve the ideal efficiency and benefits. Summary of the invention

[0003] Based on this, it is necessary to provide a powder spreading mechanism and a 3D printer that can easily and stably adjust the powder amount, has high working efficiency and a simple structure, in order to address the problems of the powder spreading mechanism used in 3D printers in the prior art that the powder spreading amount is difficult to control and the working efficiency is low.

[0004] A powder spreading mechanism, the powder spreading mechanism comprising: a mounting frame, a powder lowering component, a vibration component and a scraping component; the powder lowering component comprises a powder bin, a vibration side plate and an adjustment side plate arranged on the mounting frame, the vibration side plate and the adjustment side plate are arranged on the periphery of the powder outlet of the powder bin, and an adjustable drop-out port is formed between the vibration side plate and the adjustment side plate; the vibration component comprises a vibration main body and a vibration driving member drivingly connected to the vibration main body, the vibration main body is mounted on the mounting frame and connected to the vibration side plate; the scraping component comprises a support seat and a scraper, the support seat is mounted on the mounting frame, and the scraper is mounted on a side of the support seat close to the drop-out port, for scraping the powder spreading surface.

[0005] In one embodiment, the adjustment side plate includes a movable plate and a fixed plate, an adjustment fixing seat is installed between the movable plate and the vibration side plate, and the fixed plate is installed on a side of the movable plate away from the adjustment fixing seat through an adjustment bolt.

[0006] In one embodiment, the fixing plate is penetrated by an adjustment slot, the adjustment bolt is installed on the fixing plate through the adjustment slot, and the movable plate is movably abutted against the adjustment fixing seat.

[0007] In one of the embodiments, the movable plate and the vibrating side plate are both provided with bending portions at one end close to the blanking opening, and the two bending portions are staggered.

[0008] In one of the embodiments, a holding portion is provided at one end of the movable plate away from the blanking port for adjusting the movable plate to move up and down along the fixed plate.

[0009] In one embodiment, the scraper includes a mounting portion and a smoothing portion set at different heights, the mounting portion is connected to the bottom end of the support seat, one end of the smoothing portion is connected to the mounting portion, and the other end protrudes toward the blanking port and is set flush with the bending portion of the vibrating side plate.

[0010] In one embodiment, there are a plurality of adjusting and fixing seats, and each of the adjusting and fixing seats is disposed between the movable plate and the vibrating side plate at intervals.

[0011] In one of the embodiments, the support base is arranged close to one side of the vibration side plate.

[0012] In one of the embodiments, end side plates are respectively provided at both ends of the vibration side plate and the adjustment side plate.

[0013] In one of the embodiments, the powder bin is provided with a conveying component, and the conveying component is used to convey powder to the powder bin.

[0014] In one embodiment, the conveying assembly includes a conveying agitator wheel and a conveying drive member, the conveying agitator wheel is installed in the powder bin, and the conveying drive member is driven and connected to the conveying agitator wheel to convey the powder from the powder inlet of the powder bin to the powder outlet of the powder bin.

[0015] In one embodiment, the conveying component also includes a powder detection component, which includes an electrically connected position sensor and a controller. The position sensor is installed on the powder bin, and the controller receives a signal from the position sensor to control the powder bin feeding.

[0016] In one embodiment, the position sensor includes a light simulation detector.

[0017] In one embodiment, the vibration body includes an eccentric sleeve connecting member, a swing connecting member and an intermediate connecting member. The eccentric sleeve connecting member is connected to the vibration driving member and is installed on the mounting frame. The swing connecting member is connected to the vibration side plate. The intermediate connecting member respectively connects the eccentric sleeve connecting member and the swing connecting member.

[0018] In one of the embodiments, side scrapers are also provided at both ends of the vibrating side plate.

[0019] A 3D printer comprises the powder spreading mechanism of any one of the above embodiments.

[0020] The above-mentioned powder spreading mechanism and 3D printer, by arranging a vibrating side plate and an adjusting side plate on both sides of the powder outlet of the powder bin, utilize the adjustability of the adjusting side plate to adjust the size of the drop opening so as to control the amount of powder dropped, and by arranging a vibration component of an independent structure connected to the vibrating side plate, a uniform powder dropping effect is achieved, and at the same time, the vibration component of the independent structure can be disassembled separately, which is convenient for maintenance and installation; further, a scraper is arranged on the mounting frame through a support seat, so as to prevent the scraper from being affected by vibration, realize independent scraping of the powder spreading surface, ensure the quality of sand spreading, and at the same time help to improve the sand spreading efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the three-dimensional structure of a powder spreading mechanism according to an embodiment.

[0022] Figure 2 for Figure 1 A schematic diagram of the three-dimensional structure of the powder spreading mechanism from another perspective is shown.

[0023] Figure 3 It is a partial structural schematic diagram of a powder spreading mechanism of an embodiment.

[0024] Figure 4 It is a partial structural schematic diagram of a powder spreading mechanism of yet another embodiment. DETAILED DESCRIPTION

[0025] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly understood.

[0026] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or there may be a centered element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a centered element at the same time. The terms "vertical", "horizontal", "left", "right", "top", "bottom", "bottom end", "top end" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0028] In one embodiment, a powder spreading mechanism comprises: a mounting frame, a powder lowering assembly, a vibration assembly and a scraping assembly; the powder lowering assembly comprises a powder bin, a vibration side plate and an adjustment side plate arranged on the mounting frame, the vibration side plate and the adjustment side plate are arranged on the periphery of a powder outlet of the powder bin, and a material drop opening with adjustable size is formed between the vibration side plate and the adjustment side plate; the vibration assembly comprises a vibration main body and a vibration driving member drivingly connected to the vibration main body, the vibration main body is mounted on the mounting frame and connected to the vibration side plate; the scraping assembly comprises a support seat and a scraper, the support seat is mounted on the mounting frame, and the scraper is mounted on a side of the support seat close to the material drop opening, for scraping the powder spreading surface.

[0029] In one embodiment, a 3D printer includes a powder spreading mechanism, which includes: a mounting frame, a powder lowering assembly, a vibration assembly and a scraping assembly; the powder lowering assembly includes a powder bin, a vibration side plate and an adjustment side plate arranged on the mounting frame, the vibration side plate and the adjustment side plate are arranged on the periphery of a powder outlet of the powder bin, and an adjustable drop opening is formed between the vibration side plate and the adjustment side plate; the vibration assembly includes a vibration body and a vibration driving member drivingly connected to the vibration body, the vibration body is mounted on the mounting frame and connected to the vibration side plate; the scraping assembly includes a support seat and a scraper, the support seat is mounted on the mounting frame, and the scraper is mounted on a side of the support seat close to the drop opening for scraping the powder spreading surface.

[0030] The above-mentioned powder spreading mechanism and 3D printer, by arranging a vibrating side plate and an adjusting side plate on both sides of the powder outlet of the powder bin, utilize the adjustability of the adjusting side plate to adjust the size of the drop opening so as to control the amount of powder dropped, and by arranging a vibration component of an independent structure connected to the vibrating side plate, a uniform powder dropping effect is achieved, and at the same time, the vibration component of the independent structure can be disassembled separately, which is convenient for maintenance and installation; further, a scraper is arranged on the mounting frame through a support seat, so as to prevent the scraper from being affected by vibration, realize independent scraping of the powder spreading surface, ensure the quality of sand spreading, and at the same time help to improve the sand spreading efficiency.

[0031] The powder spreading mechanism is described below in conjunction with a specific embodiment to further understand the inventive concept of the powder spreading mechanism. Figure 1 and Figure 2 , a powder spreading mechanism 10, the powder spreading mechanism includes: a mounting frame 100, a powder lowering component 200, a vibration component 300 and a leveling component 400; wherein the powder lowering component 200, the vibration component 300 and the leveling component 400 are all mounted on the mounting frame 100. Specifically, the mounting frame 100 is a square steel sheet metal, which is used to install the powder spreading mechanism on the frame of the 3D printer. Furthermore, the powder lowering component 200 is a structure for holding powder and controlling the falling of powder, the vibration component 300 is connected to the powder lowering component 200 to control the uniformity of powder falling of the powder lowering component 200, and the leveling component 400 is directly connected to the mounting frame 100, is not affected by vibration, and is used to level and compact the powder spreading surface. For the specific structure of each component, please refer to the following embodiments for detailed description:

[0032] Please continue reading Figure 1 and Figure 2 , the powder lowering assembly 200 includes a powder bin 210, a vibrating side plate 220 and an adjusting side plate 230 arranged on the mounting frame 100, the vibrating side plate 220 and the adjusting side plate 230 are arranged at the periphery of the powder outlet 240 of the powder bin, and a drop opening 250 of adjustable size is formed between the vibrating side plate 220 and the adjusting side plate 230. In one embodiment, the powder bin 210 has a receiving cavity, a cover plate is arranged at the top of the receiving cavity, and the powder outlet 240 is opened at one end of the receiving cavity away from the cover plate. Further, a powder inlet is arranged on the cover plate. Further, the powder inlet is arranged at one end of the cover plate. In this way, the powder can fall into the receiving cavity through the powder inlet on the cover plate, and further fall through the powder outlet. Since the vibrating side plate 220 and the adjusting side plate 230 are arranged at the periphery of the powder outlet, the powder can smoothly fall onto the powder laying surface along the drop opening 250 formed by the two.

[0033] Please also read Figure 3In one embodiment, the two ends of the vibration side plate 220 and the adjustment side plate 230 are respectively provided with end side plates 260. Specifically, the vibration side plates 220 and the adjustment side plates 230 are symmetrically arranged at intervals on both sides of the powder outlet 240, and the end side plates 260 are arranged at the ends of the vibration side plates 220 and the adjustment side plates 230, so as to form a relatively closed and independent powder dropping mechanism. In other words, the vibration side plate 220, the adjustment side plate 230 and the two end side plates 260 form another accommodating chamber close to the powder bin 210, which is used to temporarily store the powder falling from the powder bin.

[0034] In order to smoothly carry out the feeding operation, in one embodiment, the powder bin 210 is provided with a conveying assembly 500, and the conveying assembly 500 is used to convey powder to the powder bin. Specifically, the conveying assembly 500 includes a conveying stirring wheel 510 and a conveying driving member 520, and the conveying stirring wheel 510 is installed in the powder bin 210, and the conveying driving member 520 drives and connects the conveying stirring wheel 510, and is used to convey the powder from the powder inlet of the powder bin 210 to the powder outlet of the powder bin. Specifically, when the powder at the powder inlet falls into the powder bin, it is evenly conveyed from one end of the powder bin to the other end through the conveying stirring wheel 510, so that the entire powder feeding process is uniform and the powder in the powder bin is evenly placed.

[0035] In order to monitor the powder level in the powder bin at any time, in one embodiment, the conveying assembly also includes a powder detection member 530, and the powder detection member 530 includes an electrically connected position sensor and a controller, the position sensor is installed on the powder bin, and the controller receives the signal of the position sensor to control the feeding of the powder bin. In one embodiment, the position sensor includes a light simulation detector. When designing the powder bin, the minimum powder height and the maximum powder height are pre-set according to the workload, and the position sensor is set to detect the current powder height by light detection or other detection methods, so that the data can be transmitted to the controller at any time for analysis and comparison to see whether the critical powder height is reached, so as to make powder feeding control commands at any time.

[0036] In order to achieve the adjustable size of the blanking opening formed between the vibrating side plate and the adjusting side plate, please refer to Figure 3 and Figure 4In a specific embodiment, the adjustment side plate 230 includes a movable plate 231 and a fixed plate 232, and an adjustment fixing seat 240 is installed between the movable plate 231 and the vibration side plate 220, and the fixed plate 232 is installed on the side of the movable plate 231 away from the adjustment fixing seat 240 through the adjustment bolt 233. That is, the movable plate 231 is installed on the vibration side plate 220 through the adjustment fixing seat 240. It should be noted that the installation position of the adjustment fixing seat 240 needs to be set away from the blanking port 250 to avoid the adjustment fixing seat 240 affecting the blanking. In one implementation, there are multiple adjustment fixing seats 240, and each of the adjustment fixing seats 240 is arranged between the movable plate 231 and the vibration side plate 220 at intervals. It should be understood that the powder spreading mechanism for a 3D printer has a long horizontal length. When installing the adjustment side plate, setting multiple adjustment fixing seats 240 is conducive to more stably installing the adjustment side plate as a whole on the vibration side plate.

[0037] Furthermore, the fixed plate 232 is provided with an adjustment slot, and the adjustment bolt 233 is installed on the fixed plate 232 through the adjustment slot, and movably abuts the movable plate 231 on the adjustment fixing seat 240. That is to say, the movable plate 231 is movably pressed between the fixed plate 232 and the adjustment fixing seat 240. Specifically, when the adjustment bolt 233 is loosened, a movable gap can be formed between the movable plate 231 and the fixed plate 232, and the size of the blanking opening 250 formed between the movable plate 231 and the vibration side plate 220 can be adjusted by pulling the movable plate 231 up and down. When the position of the movable plate 231 needs to be fixed after adjustment, the movable plate 231 can be pressed between the adjustment fixing seat 240 and the fixed plate 232 by tightening the adjustment bolt 233.

[0038] In order to facilitate the formation of a stacking angle that can control the powder falling, in one embodiment, the movable plate 231 and the end of the vibrating side plate 220 close to the material drop opening 250 are both provided with a bending portion, and the two bending portions are staggered. In other words, a staggered platform is formed between the movable plate 231 and the bending portion of the vibrating side plate 220. When the powder is accumulated on the bending portion, a stacking angle is formed. By adjusting the movable plate 231, the size of the material drop opening 250 in the vertical direction can be adjusted, and then the amount of powder dropped can be adjusted.

[0039] In order to facilitate the operation of the movable plate to move up and down, in one embodiment, a holding portion is provided at one end of the movable plate 231 away from the blanking port 250, for adjusting the movable plate 231 to move up and down along the fixed plate 232. The structure of the holding portion can be any structure that is easy to hold, and is not specifically limited in this embodiment.

[0040] Please also read Figure 3 and Figure 4The vibration assembly 300 includes a vibration body 310 and a vibration driving member 320 drivingly connected to the vibration body. The vibration body 310 is mounted on the mounting frame 100 and connected to the vibration side plate 220. In one embodiment, the vibration body 310 includes an eccentric sleeve connecting member 311, a swing connecting member 312 and an intermediate connecting member 313. The eccentric sleeve connecting member 311 is connected to the vibration driving member 320 and is mounted on the mounting frame 100. The swing connecting member 312 is connected to the vibration side plate 220. The intermediate connecting member 313 connects the eccentric sleeve connecting member 311 and the swing connecting member 312 respectively. The linkage triangle assembly formed by the eccentric sleeve connecting member 311, the swing connecting member 312 and the intermediate connecting member 313 swings around the rotation point of the swing connecting member 312. The vibration side plate 220 is fixedly connected to the swing connecting member 312 and swings accordingly to realize vibration linkage, so that the vibration side plate 220 vibrates the powder to fall evenly.

[0041] Please refer again Figure 3 and Figure 4 , the scraping assembly 400 includes a support seat 410 and a scraper 420, the support seat 410 is installed on the installation frame 100, and the scraper 420 is installed on the side of the support seat 410 close to the blanking port 250, and is used to scrape the powder surface. In one embodiment, the support seat 410 is arranged close to the side of the vibration side plate 220. That is to say, the scraper 420 is arranged on the side where the vibration assembly is installed in the powder spreading mechanism, which is conducive to the scraper 420 to compact the powder surface tightly according to the powder spreading direction. Further, the scraper 420 includes a mounting portion and a smoothing portion with different heights, the mounting portion is connected to the bottom end of the support seat, one end of the smoothing portion is connected to the mounting portion, and the other end protrudes toward the blanking port 250 and is arranged flush with the bending portion of the vibration side plate 220. It should be noted that the scraper 420 is arranged at intervals from the bending portion of the vibration side plate 220, so that it is safe from the influence of the vibration assembly when scraping and compacting the powder surface. In this way, by arranging the scraper plate flush with the bent portion of the vibrating side plate 220, it is more conducive to simultaneously and seamlessly compacting and leveling the powder surface when powder is applied.

[0042] In order to clean up the excess powder on the work surface in time during the powder spreading process, in one embodiment, please refer to Figure 1 , side scrapers 270 are also provided at both ends of the vibrating side plate 220. That is, side scrapers 270 are provided protrudingly at both ends of the powder spreading mechanism, and the side scrapers 270 are provided beyond the powder spreading surface. When excess powder is accumulated on the work surface, the side scrapers 270 can be used to push the powder at the edge of the powder spreading surface, and finally push the powder to the sand cleaning bin provided at the bottom of the frame of the 3D printer as the powder spreading mechanism moves.

[0043] In one embodiment, a 3D printer includes the powder spreading mechanism 10 described in any one of the above embodiments.

[0044] The above-mentioned powder spreading mechanism and 3D printer, by arranging a vibrating side plate 220 and an adjusting side plate 230 on both sides of the powder outlet of the powder bin 210, utilize the adjustability of the adjusting side plate 230 to adjust the size of the drop opening so as to control the amount of powder released, and by arranging a vibration component 300 of an independent structure connected to the vibrating side plate 220, a uniform powder release effect is achieved, and at the same time, the vibration component of the independent structure can be disassembled separately, which is convenient for maintenance and installation; further, a scraper 420 is arranged on the mounting frame through the support seat 410, so as to prevent the scraper from being affected by vibration, realize independent scraping of the powder spreading surface, ensure the quality of sand spreading, and at the same time help to improve the sand spreading efficiency.

[0045] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0046] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A powder spreading mechanism, characterized in that: The powder spreading mechanism comprises: a mounting frame, a powder lowering assembly, a vibration assembly and a scraping assembly; the powder lowering assembly comprises a powder bin, a vibration side plate and an adjustment side plate arranged on the mounting frame, the vibration side plate and the adjustment side plate are arranged on the periphery of the powder outlet of the powder bin, and an adjustable drop opening is formed between the vibration side plate and the adjustment side plate; the vibration assembly comprises a vibration main body and a vibration driving member drivingly connected to the vibration main body, the vibration main body is mounted on the mounting frame and connected to the vibration side plate; the scraping assembly comprises a support seat and a scraper, the support seat is mounted on the mounting frame, and the scraper is mounted on a side of the support seat close to the drop opening for scraping the powder spreading surface; The adjustment side plate comprises a movable plate and a fixed plate, an adjustment fixing seat is installed between the movable plate and the vibration side plate, and the fixed plate is installed on a side of the movable plate away from the adjustment fixing seat through an adjustment bolt.

2. The powder spreading mechanism according to claim 1, characterized in that: The fixing plate is penetrated by an adjusting slot, and the adjusting bolt is installed on the fixing plate through the adjusting slot, and the movable plate is movably abutted against the adjusting fixing seat.

3. The powder spreading mechanism according to claim 1, characterized in that: The movable plate and the vibrating side plate are both provided with bending portions at one end close to the blanking opening, and the two bending portions are staggered.

4. The powder spreading mechanism according to claim 3, characterized in that: A holding portion is provided at one end of the movable plate away from the blanking opening, and is used for adjusting the movable plate to move up and down along the fixed plate.

5. The powder spreading mechanism according to claim 3, characterized in that: The scraper includes a mounting portion and a smoothing portion which are set at different heights. The mounting portion is connected to the bottom end of the support seat. One end of the smoothing portion is connected to the mounting portion, and the other end protrudes toward the blanking port and is set flush with the bending portion of the vibrating side plate.

6. The powder spreading mechanism according to claim 1, characterized in that: There are a plurality of adjusting and fixing seats, and each of the adjusting and fixing seats is arranged between the movable plate and the vibration side plate at intervals.

7. The powder spreading mechanism according to claim 1, characterized in that: The support seat is arranged close to one side of the vibration side plate.

8. The powder spreading mechanism according to claim 1, characterized in that: End side plates are respectively arranged at both ends of the vibration side plate and the adjustment side plate.

9. The powder spreading mechanism according to claim 1, characterized in that: The powder bin is provided with a conveying assembly, and the conveying assembly is used to convey powder to the powder bin.

10. The powder spreading mechanism according to claim 9, characterized in that: The conveying assembly includes a conveying agitator wheel and a conveying drive member. The conveying agitator wheel is installed in the powder bin. The conveying drive member is driven and connected to the conveying agitator wheel to convey the powder from the powder inlet of the powder bin to the powder outlet of the powder bin.

11. The powder spreading mechanism according to claim 9, characterized in that: The conveying assembly also includes a powder detection component, which includes an electrically connected position sensor and a controller. The position sensor is installed on the powder bin, and the controller receives a signal from the position sensor to control the powder bin feeding.

12. The powder spreading mechanism according to claim 11, characterized in that: The position sensor includes a light simulation detector.

13. The powder spreading mechanism according to claim 1, characterized in that: The vibration body includes an eccentric sleeve connecting piece, a swing connecting piece and an intermediate connecting piece. The eccentric sleeve connecting piece is connected to the vibration driving piece and installed on the mounting frame. The swing connecting piece is connected to the vibration side plate. The intermediate connecting piece connects the eccentric sleeve connecting piece and the swing connecting piece respectively.

14. The powder spreading mechanism according to claim 1, characterized in that: Side scrapers are also arranged at both ends of the vibrating side plates.

15. A 3D printer, characterized in that: It comprises a powder spreading mechanism as claimed in any one of claims 1 to 14.

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