Powder spreading system and 3D printer

Abstract

The present invention relates to the field of 3D printing equipment, and discloses a powder spreading system and a 3D printer. The powder spreading system includes a powder spreading device, a first driving mechanism that drives the powder spreading device to move above a printing platform, and a powder feeding cylinder located above the printing platform. The powder spreading device includes a powder spreading cylinder with a powder outlet and a powder flattening portion for smoothing the powder, and the lower end of the powder flattening portion is horizontally parallel to the upper plane of the printing platform. The 3D printer of the present invention is provided with the above-mentioned powder spreading system. When the powder spreading device moves above the printing platform and spreads the powder, the printing material (powder) in the powder spreading cylinder can be delivered from the powder outlet and spread on the platform surface of the printing platform, and then the powder flattening portion arranged thereafter can quickly smooth the powder to form a working surface. The powder feeding cylinder is used to replenish powder to the powder spreading cylinder. The functions of powder storage, powder spreading, and smoothing are integrated, and the overall structure is compact and the working efficiency is high.

Description

Technical Field

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

[0002] 3D printer, also known as three-dimensional printer (3DP), is a kind of cumulative manufacturing technology, that is, a machine of rapid prototyping technology. It is a technology based on digital model files (CAD), using special wax materials, powdered metals or plastics and other adhesive materials to print layers of adhesive materials to manufacture three-dimensional objects. At present, 3D printers are used to manufacture products. Some systems use "laser sintering" technology to use powder particles as printing media. Powder particles are laid on the mold tray to form a powder layer of a certain thickness, which is laser melted into a specified shape. During the laying process, the powder should be evenly laid on the printing platform, otherwise it will affect the printing effect. With the existing equipment, the operation of powder supply and leveling is cumbersome to implement and the effect is not good. Summary of the invention

[0003] The object of the present invention is to provide a powder spreading system which has a compact structure and can automatically and efficiently spread powder on the platform surface of a printing platform of a 3D printer, and spread the powder evenly.

[0004] Another object of the present invention is to provide a 3D printer which has a compact structure and can automatically and efficiently perform powder spreading operations, and the powder spreading is uniform, which is conducive to simplifying the process and improving product quality.

[0005] The embodiment of the present invention is achieved as follows:

[0006] A powder spreading system, comprising:

[0007] A powder spreading device, the powder spreading device comprises a powder spreading cylinder for containing powder material and a powder leveling part, the powder leveling part is a powder leveling brush or a powder leveling roller, the powder spreading cylinder has a powder outlet for spreading powder on the printing platform, and the powder leveling part is used to smooth the powder spread on the printing platform to form a working surface;

[0008] A first driving mechanism for driving the powder spreading device to move above the working surface;

[0009] A powder feeding cylinder is arranged above the printing platform, and the powder feeding cylinder is provided with a powder feeding port. The powder feeding port is provided with a second opening and closing mechanism. The second opening and closing mechanism of the powder feeding port is used to open or close the powder feeding port. The powder feeding port is used to transport the powder in the powder feeding cylinder to the powder spreading cylinder.

[0010] In one embodiment of the present invention:

[0011] The first driving mechanism comprises a track extending in a straight direction, and the powder spreading device cooperates with the track and can move in the extending direction of the track.

[0012] In one embodiment of the present invention:

[0013] The first driving mechanism is used to drive the powder spreading device to move in a circumferential direction.

[0014] In one embodiment of the present invention:

[0015] The powder spreading device comprises two powder outlets, the two powder outlets are arranged at intervals in the moving direction of the powder spreading device, and the powder flattening part is located between the two powder outlets.

[0016] In one embodiment of the present invention:

[0017] The powder spreading device comprises two flat powder parts, the two flat powder parts are arranged at intervals in the moving direction of the powder spreading device, and the powder outlet is located between the two flat powder parts.

[0018] In one embodiment of the present invention:

[0019] A first opening and closing mechanism is arranged on the powder outlet, and the first opening and closing mechanism comprises a blocking member movably connected to the powder spreading cylinder and a second driving mechanism for driving the blocking member to open or close the powder outlet.

[0020] In one embodiment of the present invention:

[0021] The powder spreading system includes at least two powder feeding cylinders, which are fixedly arranged above the printing platform.

[0022] In one embodiment of the present invention:

[0023] The first driving mechanism includes a turntable and a first driving part for driving the turntable to rotate; the powder spreading device is rotationally connected to the turntable, and a third driving mechanism is arranged on the turntable. The third driving mechanism is used to drive the powder spreading device to rotate relative to the turntable so that it can be extended to the top of the printing platform or retracted from the top of the printing platform.

[0024] In one embodiment of the present invention:

[0025] The powder flattening part is strip-shaped and horizontally parallel to the plane on the printing platform. One end of the powder flattening part away from the turntable is radially bent inward to form a hook-shaped powder collecting part, which is used to collect excess powder on the working surface after the powder flattening part smoothes the powder.

[0026] A 3D printer comprises the above-mentioned powder spreading system.

[0027] The beneficial effects of the embodiments of the present invention are:

[0028] The powder spreading system of the embodiment of the present invention includes a powder spreading device, a first driving mechanism for driving the powder spreading device to move on the printing platform, and a powder feeding cylinder above the printing platform. The powder spreading device includes a powder spreading cylinder with a powder outlet and a powder leveling part, the powder leveling part is used to level the powder spread on the printing platform to form a working surface, and the lower end of the powder leveling part is parallel to the working surface on the printing platform. When the powder spreading device moves above the printing platform and spreads powder, the printing material (powder) in the powder spreading cylinder can be delivered from the powder outlet, spread on the platform surface of the printing platform or the working surface formed by the last powder spreading operation, and then the powder leveling part that follows can level the powder to form a new working surface. The powder feeding cylinder is used to replenish powder in the powder spreading cylinder. The functions of powder storage, powder spreading, and leveling are integrated into one, and the overall structure is compact and the work efficiency is high.

[0029] The 3D printer of the embodiment of the present invention is provided with the above-mentioned powder spreading system, and thus also has the above-mentioned beneficial effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 This is a schematic diagram of the structure of the powder spreading system according to Embodiment 1 of the present invention;

[0032] Figure 2 This is a schematic diagram of the coordination between the powder spreading device and the track according to Embodiment 1 of the present invention;

[0033] Figure 3 This is a schematic structural diagram of a powder spreading device according to Embodiment 1 of the present invention;

[0034] Figure 4 It is a variation of the powder spreading device of embodiment 1 of the present invention;

[0035] Figure 5 This is a schematic structural diagram of a 3D printer according to Embodiment 1 of the present invention;

[0036] Figure 6 This is a schematic diagram of the arrangement of the powder spreading system of Example 2 of the present invention on a 3D printer;

[0037] Figure 7 is a schematic diagram of a third driving mechanism of Embodiment 2 of the present invention;

[0038] Figure 8 This is a schematic diagram of the structure of a powder spreading device according to Embodiment 2 of the present invention;

[0039] Fig. 9 A variation of the mounting portion of embodiment 2 of the present invention;

[0040] Fig.10 This is a schematic diagram of the arrangement of the powder delivery cylinder of Example 2 of the present invention.

[0041] Icons: 100-powder spreading system; 101-platform surface; 110-powder spreading device; 111-powder spreading cylinder; 111a-powder outlet; 111b-powder inlet; 112-powder leveling part; 113-mounting frame; 114-chute; 115-first opening and closing mechanism; 116-second driving part; 117-blocking member; 120-first driving part; 122-driven part; 124-convex belt; 126-track; 127-convex part; 130-powder feeding cylinder; 132-second opening and closing mechanism; 200-3D Printer; 210-printing platform; 212-powder collecting cylinder; 300-powder spreading system; 310-powder spreading device; 311-powder spreading cylinder; 311a-powder outlet; 312-powder leveling part; 313-mounting frame; 320-turntable; 322-fixed seat; 324-mounting part; 330-third driving part; 332-driving gear; 334-shaft; 336-driven gear; 340-powder collecting part; 350-powder feeding cylinder; 400-3D printer; 410-printing platform; 412-powder collecting cylinder. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0043] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0045] In the description of the embodiments of the present invention, it should be noted that the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the inventive product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0046] In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0047] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0048] Example 1

[0049] Figure 1 This is a schematic diagram of the structure of the powder spreading system 100 according to Embodiment 1 of the present invention. Figure 1 This embodiment provides a powder spreading system 100, which includes a printing platform 210 (see Figure 5 ), a powder spreading device 110 above the platform surface 101, a first driving mechanism driving the powder spreading device 110 to move above the platform surface 101, and a powder feeding cylinder 130 located above the moving plane of the powder spreading device 110. The powder feeding cylinder 130 is used to store materials required for printing and can supply printing materials to the powder spreading device 110. In this embodiment, the printing material is a powder material. When the powder spreading device 110 moves on the platform surface 101, it can release the powder onto the printing platform 210. The powder flattening part 112 on the powder spreading device 110 can smooth the powder, and the upper surface of the powder forms a working surface, so that the powder can be in a better printing state during subsequent printing, thereby improving product quality. Through such a structural design, the powder spreading system 100 with powder storage and powder spreading is integrated and arranged as a whole above the platform surface 101, which can effectively reduce the overall volume of the printing equipment and improve work efficiency.

[0050] In this embodiment, the first driving mechanism includes a first driving part 120, a driven part 122, a conveyor belt 124 that is transmission-connected between the first driving part 120 and the driven part 122, and a track 126 extending in a straight direction. The powder spreading device 110 cooperates with the track 126 and can make a straight-line motion back and forth in the extension direction of the track 126, and the powder spreading operation can be completed during the motion. The conveyor belt 124 is connected to the powder spreading device 110 so that it can pull the powder spreading device 110 to move on the track 126. The first driving part 120 is a stepping motor that drives a pulley to rotate, and the driven part 122 is a driven pulley arranged near the other end of the track 126. The two pulleys are near the two ends of the track 126 and enable the conveyor belt 124 to be parallel to the track 126. It should be understood that in other embodiments of the present invention, the first driving mechanism may also adopt other transmission methods such as chain drive, rack drive, etc. Correspondingly, the pulley in this embodiment should be replaced by a sprocket, rack, etc., and the conveyor belt 124 in this embodiment should be replaced by a chain, rack, etc.

[0051] Figure 2 Schematic diagram of the coordination between the powder spreading device 110 and the track 126 according to the first embodiment of the present invention. Figure 1 and Figure 2 In this embodiment, in order to ensure the stability of the powder spreading device 110 during movement, two parallel tracks 126 are arranged on the platform surface 101, and the two sides of the powder spreading device 110 in the movement direction are respectively matched with the tracks 126. Accordingly, the two sides of the two tracks 126 correspond to a conveyor belt 124 driven by the first driving unit 120, so that the first driving mechanism can apply a drag force from both sides of the powder spreading device 110 to drive the powder spreading device 110.

[0052] Figure 3 This is a schematic diagram of the structure of the powder spreading device 110 according to Embodiment 1 of the present invention. Figure 1 and Figure 3In this embodiment, the powder spreading device 110 includes a powder spreading cylinder 111 for containing powder materials and a powder flattening portion 112 arranged on the powder spreading cylinder 111. The powder spreading cylinder 111 has a powder outlet 111a for supplying powder to the platform surface 101 of the printing platform 210. The lower end of the powder flattening portion 112 is horizontally parallel to the platform surface 101 of the printing platform 210, so that the powder brushed by the powder flattening portion 112 has a uniform certain thickness, which is consistent with the thickness of the current working layer. The upper surface of the powder smoothed by the powder flattening portion 112 is the working surface, and the printing device (not shown) can perform printing operations on the powder on the working surface. The powder flattening part 112 of the present embodiment is a powder flattening brush with bristles, which smoothes the powder by using the bristles facing downwards. In other embodiments of the present invention, the powder flattening part 112 may be modified to a certain extent. For example, the bristles may be changed to a scraper, the lower side of the scraper is parallel to the working surface; or the powder flattening part 112 is configured as a powder flattening roller, the lower end parallel surface of the powder flattening roller is horizontally parallel to the platform surface 101.

[0053] In this embodiment, the powder spreading cylinder 111 has two chambers separated in the direction of movement, and the tops of the two chambers have powder inlets 111b, which are used to receive powder sent from the feeding port at the bottom of the powder feeding cylinder 130. The bottoms of the two chambers each have a powder outlet 111a, and the two powder outlets 111a are spaced apart in the direction of movement of the powder spreading device 110, and the powder flattening portion 112 is located between the two powder outlets 111a. In this way, the powder spreading device 110 can be moved left and right (with the powder flattening portion 112 positioned between the powder flattening portions 112 and the powder flattening portions 112). Figure 1 When the powder spreading device 110 moves to the left, the powder outlet 111a on the left is used to spread the powder, and the powder outlet 111a on the left is closed. The powder falling from the powder outlet 111a on the right will then be smoothed by the powder leveling part 112, achieving a uniform laying effect. Similarly, when the powder spreading device 110 moves to the left, the powder outlet 111a on the left is used to spread the powder, and the powder leveling part 112 can also smooth the powder in time. In this way, the powder can be spread back and forth, and the leveling and powder collecting operations can be completed without adjusting the position of the powder leveling part 112, and the efficiency is significantly improved.

[0054] In order to replenish the powder in the two chambers in time, the two powder feeding cylinders 130 are respectively arranged above the two ends of the track 126 and fixedly installed, so that when the powder spreading cylinder 111 moves to the left end, the chamber powder inlet 111b on the right side is just located below the feeding port of the left powder feeding cylinder 130; when the powder spreading cylinder 111 moves to the right end of the track 126, the chamber powder inlet 111b on the left side is just located below the feeding port of the right powder feeding cylinder 130. In other embodiments of the present invention, the two chambers of the powder spreading cylinder 111 can also be combined into one, without a partition in the middle, and the two powder outlets 111a share the powder of the entire chamber.

[0055] In other embodiments of the present invention, the structure of the powder spreading device 110 may be changed. Figure 4 This is a variation of the powder spreading device 110 of embodiment 1 of the present invention. Figure 4 , the powder spreading cylinder 111 may be provided with only one powder outlet 111a, and a powder flattening portion 112 is provided on each of the left and right sides of the powder outlet 111a. Such a structure can also realize powder spreading when moving in the left and right directions. When moving to the left, the powder flattening portion 112 on the right is smoothed; and when moving to the right, the powder flattening portion 112 on the left is smoothed. The effect is the same as that of the present embodiment, and powder spreading in two directions is also realized without adjusting the orientation of the powder flattening portion 112. It should be noted that when the powder spreading device 110 starts the powder spreading operation, the flat working surface on the printing platform 210 is not formed. At this time, the area of ​​the pre-formed working surface on the printing platform 210 is lower than the platform surface 101. When the powder spreading device 110 starts working, no matter it works to the left or right, the powder flattening portion 112 passing in front will not affect the powder spreading and powder flattening operations behind it.

[0056] Please combine Figures 1 to 3 In this embodiment, the powder leveling part 112 is fixed on the mounting frame 113. The mounting frame 113 of this embodiment is in the shape of a strip and extends to both sides of the movement direction of the powder spreading device 110. The powder leveling part 112 is fixed to the lower side of the mounting frame 113, and its bristles face downward. A sliding part is respectively provided at both ends of the mounting frame 113. The sliding part has a slide groove 114 with an opening facing downward. The slide groove 114 cooperates with a convex part 127 protruding upward on the track 126. The convex part 127 extends along the length direction of the track 126 and is equal to the track 126. In this embodiment, in order to prevent the powder spreading device 110 from falling off the track 126, from the cross-section, the upper end of the convex part 127 has a triangular clamping part, and the width of the clamping part is greater than the width of the bottom end of the convex part 127, so that the cross-section of the entire convex part 127 forms an upward arrow shape. It should be understood that in other embodiments of the present invention, the shapes of the protrusion 127 and the slide groove 114 can be changed, such as designing the slide groove 114 and the protrusion 127 to be dovetail-shaped; and the setting positions of the protrusion 127 and the slide groove 114 can be changed, such as setting the protrusion 127 on the sliding part and setting the slide groove 114 on the track 126.

[0057] In the present embodiment, the powder outlet 111a of the powder spreading cylinder 111 is provided with a first opening and closing mechanism 115, which is used to open or close the powder outlet 111a to realize free powder supply. In the present embodiment, the first opening and closing mechanism 115 includes a blocking member 117 rotatably connected to the powder spreading cylinder 111 and a second driving mechanism for driving the blocking member 117 to open or close the powder outlet 111a. Further, the powder outlet 111a is a strip-shaped opening perpendicular to the movement direction of the powder spreading device 110, and correspondingly, the blocking member 117 is a strip-shaped sealing plate, one side of the blocking member 117 is fixedly connected to a rotating shaft, and the rotating shaft is rotatably connected to the powder spreading cylinder 111. When the rotating shaft rotates, the blocking member 117 can follow the rotation to open or close the powder outlet 111a. The second driving mechanism includes a second driving part 116 fixed to the powder spreading cylinder 111, a driving sprocket connected to the second driving part 116, and a driven sprocket arranged on the rotating shaft, and the driving sprocket and the driven sprocket are driven by a chain. It should be understood that in other embodiments of the present invention, the second driving mechanism can also drive the rotating shaft to rotate in other ways, for example, the second driving machine drives the rotating shaft to rotate through a belt drive or a gear meshing drive.

[0058] In order to enable the feeding port of the powder feeding cylinder 130 to have the function of automatic opening and closing, a second opening and closing mechanism 132 is provided at the feeding port. The second opening and closing mechanism 132 of this embodiment is similar to the first opening and closing mechanism 115 in structure and function, and will not be repeated here.

[0059] In this embodiment, the two rails 126 are made of metal material and thus have electrical conductivity. The two rails 126 are electrically connected to a power source (not shown) and are respectively positive and negative, and the rails 126 can provide power to the first drive mechanism. It should be understood that in other embodiments of the present invention, the rails 126 may also be partially made of metal, the metal part acts as an electrical conductor, and the rest is set as an insulating material to ensure safety.

[0060] Figure 5 This is a schematic diagram of the structure of the 3D printer 200 according to Embodiment 1 of the present invention. Figure 5 The present embodiment provides a 3D printer 200, which includes a printing platform 210, a printing device (not shown) disposed above the printing platform 210, and a powder spreading system 100 disposed above the printing platform 210. Two powder collecting cylinders 212 are disposed above the platform surface 101 of the printing platform 210, and the two powder collecting cylinders 212 are respectively located at both ends of the extension direction of the track 126, so that when the powder flattening part 112 moves to the leftmost end or the rightmost end with the powder spreading device 110, the excess powder can be swept into the powder collecting cylinder 212 for collection, which is conducive to the reuse of the powder.

[0061] The working principles of the powder spreading device 110 and the 3D printer 200 of this embodiment are:

[0062] The powder spreading device 110 moves back and forth in a straight line above the platform surface 101 and spreads powder back and forth. The powder leveling portion 112 following the powder outlet 111a can smooth the powder in time, and can collect excess powder into the powder collecting cylinder 212 when it moves to the end in one direction. The powder spreading device 110 moves from one end of the track 126 to the other end to spread powder. When it reaches the end, the powder feeding cylinder 130 above the powder spreading cylinder 111 can be used to replenish powder. After the powder is spread, the printing device can perform printing operations on the powder. After the first layer of printing is completed, the height of the printing platform 210 is lowered, and subsequent powder spreading and printing are performed, and this cycle is repeated. Such a powder spreading device 110 and a 3D printer 200 integrate the relevant equipment for storing powder, spreading powder, leveling powder, and collecting powder, and are arranged above the printing platform 210, making the equipment more compact and increasing space utilization. And the overall performance is stable, powder can be spread back and forth, and the work efficiency is higher.

[0063] Example 2

[0064] Figure 6 The figure is a schematic diagram of the arrangement of the powder spreading system 300 of the second embodiment of the present invention on the 3D printer 400. Please refer to the figure, the present embodiment provides a powder spreading system 300 and a 3D printer 400, and the powder spreading system 300 of the present embodiment is used to be arranged on a printing platform 410 having an annular platform surface 101. The powder spreading system 300 includes a first driving mechanism, a third driving mechanism and a powder spreading device 310. The third driving mechanism is arranged on the first driving mechanism, and the powder spreading device 310 is connected to the third driving mechanism in a transmission manner, so that the first driving mechanism can drive the third driving mechanism and the powder spreading device 310 to rotate together above the printing platform 410; and the third driving mechanism can further drive the powder spreading device 310 to rotate relative to the first driving mechanism. The 3D printer 400 of the present embodiment includes a printing platform 410 having a platform surface 101, a powder collecting cylinder 412 inside the platform surface 101, and a printing device (not shown) above the platform surface 101.

[0065] In this embodiment, the first driving mechanism includes a turntable 320 and a first driving unit (not shown) driving the turntable 320 to rotate, and the plane where the turntable 320 is located is parallel to the platform surface 101 of the printing platform 410. In this embodiment, in order to achieve better rotational cooperation between the turntable 320 and the printing platform 410, a roller (not shown) is provided at the bottom of the turntable 320, and the first driving unit is a stepping motor in this embodiment.

[0066] In this embodiment, the turntable 320 is located inside the annular platform surface 101 and is coaxially arranged therewith. A fixing seat 322 is arranged near the edge of the turntable 320, and the fixing seat 322 is used to be rotatably connected with the powder spreading device 310, so that the powder spreading device 310 can rotate relative to the turntable 320, so that the powder spreading device 310 can be extended out of the platform surface 101 or retracted from above the platform surface 101.

[0067] Figure 7 Schematic diagram of the third driving mechanism of Example 2 of the present invention. Figure 6 and Figure 7 In this embodiment, two mounting parts 324 are provided on the fixing seat 322 , and the two mounting parts 324 protrude in the horizontal direction and are arranged at intervals in the height direction. The free ends of the two mounting parts 324 have vertical through holes for being hinged with the powder spreading device 310 .

[0068] Figure 8 This is a schematic diagram of the structure of the powder spreading device 310 according to Embodiment 2 of the present invention. Figures 6 to 8 In this embodiment, the powder spreading device 310 includes a powder spreading cylinder 311 and a powder leveling portion 312 fixedly connected to the powder spreading cylinder 311, the powder leveling portion 312 includes a strip-shaped mounting frame 313, the bristles are arranged on the mounting frame 313 and face downward, and the powder spreading cylinder 311 is fixed to the mounting frame 313. In this embodiment, the mounting frame 313 is longer than the radial dimension of the powder spreading cylinder 311 in the annular path (here, it refers to above the platform surface 101, in the working state), and one end of the mounting frame 313 close to the inner side of the annular path extends radially inward and is hinged between the two mounting portions 324 through a shaft 334. The third driving mechanism includes a shaft 334 arranged at one end of the inner side of the mounting frame 313, a driven gear 336 arranged on the shaft 334, a third driving portion 330, and a driving gear 332 connected to the rotating shaft of the third driving portion 330. The end of the mounting frame 313 has a notch, and the shaft 334 runs through both sides of the notch, and the part located in the notch is fixedly provided with a driven gear 336. The shaft 334 is fixedly connected to the mounting frame 313, and its two ends protrude from both sides of the length direction of the mounting frame 313, and the two ends are hinged with the through hole of the mounting portion 324. The driven gear 336 is relatively fixed to the shaft 334, and the third driving unit 330 is fixedly provided on the turntable 320 and can drive the driving gear 332 to rotate. The driving gear 332 is meshed with the driven gear 336, so that the third driving unit 330 can drive the mounting frame 313 to drive the powder spreading cylinder 311 to rotate relative to the turntable 320. In the present embodiment, the third driving unit 330 is a stepping motor, and it should be understood that in other embodiments, the third driving unit 330 can also be other types of motors.

[0069] In other embodiments of the present invention, the shaft 334 can also be a bolt that vertically penetrates the mounting portion 324 and the mounting frame 313, and at the same time passes through the driven gear 336 and is fixed to the driven gear 336, and is fastened using a nut and a bolt to fix the bolt and the driven gear 336 relative to the mounting frame 313. Fig. 9 This is a variation of the mounting portion 324 of Embodiment 2 of the present invention. Fig. 9 In this case, the free end of the mounting portion 324 can be set as a bearing, the bolt is fixed to the inner ring of the bearing, and the mounting portion 324 is fixed to the outer ring of the bearing, so that the mounting frame 313 can rotate around the mounting portion 324.

[0070] In this embodiment, the powder spreading cylinder 311 is provided with a powder outlet 311a, and the powder outlet 311a is located in front of the moving direction relative to the flat powder portion 312, so that the powder delivered by the powder outlet 311a can be smoothed by the flat powder portion 312 in time. Similar to Example 1, only the double cavity structure in Example 1 is set as a single cavity structure, and only has a strip-shaped powder outlet 311a. Similarly, the powder outlet 311a of this embodiment is also switched by the same opening and closing mechanism, and the opening and closing mechanism is connected to a power source (not shown), and the specific structure of the opening and closing mechanism is not described here.

[0071] The powder flattening portion 312 is strip-shaped and parallel to the platform surface 101. One end of the powder flattening portion 312 away from the turntable 320 radially exceeds the outside of the powder spreading device 310 and bends radially inward to form a hook-shaped powder collecting portion 340. When the third driving portion 330 drives the powder spreading device 310 to rotate relative to the turntable 320 and is retracted from the platform surface 101, the powder collecting portion 340 can better collect excess powder from the printing platform 410 into the powder collecting cylinder 412. The powder collecting cylinder 412 in this embodiment is an annular trough body, which is arranged between the turntable 320 and the platform surface 101. When the powder spreading device 310 is retracted, the powder flattening portion 312 can collect excess powder into the powder collecting cylinder 412 for reuse.

[0072] In this embodiment, four powder spreading devices 310 and corresponding first driving mechanisms and second driving mechanisms are connected to the rotating disk 320. In other embodiments of the present invention, the number of powder spreading devices 310 can be increased or decreased. Fig.10 FIG. 3 is a schematic diagram of the arrangement of the powder delivery cylinder 350 according to Embodiment 2 of the present invention. Fig.10 The powder spreading system 300 further includes four powder feeding cylinders 350 disposed above the annular platform surface 101, and the four powder feeding cylinders 350 correspond to the four powder spreading devices 310 respectively. Similar to the function in Example 1, the powder feeding cylinders 350 can store powder and provide an appropriate amount of powder to the powder spreading cylinders 311 when the powder spreading device 310 is retracted from the printing platform 410 to the turntable 320.

[0073] The working principles of the powder spreading system 300 and the 3D printer 400 of this embodiment are:

[0074] The turntable 320 drives four powder spreading devices 310 to move on the annular platform surface 101 to spread powder. The powder spreading device 310 is connected to the turntable 320 through a third driving mechanism, so that the powder spreading device 310 can rotate relative to the turntable 320. Therefore, the third driving mechanism can control the powder spreading device 310 to extend above the platform surface 101 or retract from above the platform surface 101 for the printing device to print the powder. When the powder spreading device 310 is retracted, the powder collecting part 340 at the free end of the powder leveling part 312 can "catch" the powder, and better collect the excess powder into the powder collecting cylinder 412. The powder spreading system 300 of this embodiment is suitable for a printer with an annular platform surface 101, and its functions of spreading powder, leveling powder, and collecting excess powder are integrated into one, with a compact structure and high working efficiency.

[0075] In summary, the powder spreading system of an embodiment of the present invention includes a powder spreading device and a first driving mechanism that drives the powder spreading device to move on the printing platform. The powder spreading device includes a powder spreading cylinder with a powder outlet and a powder leveling portion for leveling the powder, and the lower end of the powder leveling portion is horizontally parallel to the platform surface of the printing platform. When the powder spreading device moves above the printing platform and spreads the powder, the printing material (powder) in the powder spreading cylinder can be delivered from the powder outlet and spread on the platform surface of the printing platform or the working surface formed by the last powder spreading operation, and then the powder leveling portion that follows can level the powder to form a new working surface. The functions of powder spreading and leveling are integrated into one, and the overall structure is compact and the work efficiency is high.

[0076] The 3D printer of the embodiment of the present invention is provided with the above-mentioned powder spreading system, and thus also has the above-mentioned beneficial effects.

[0077] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A powder spreading system, characterized in that: The powder spreading system comprises: A powder spreading device, the powder spreading device comprising a powder spreading cylinder for containing powder material and a powder leveling part, the powder leveling part being a powder leveling brush or a powder leveling roller, the powder spreading cylinder having a powder outlet for spreading powder onto the printing platform, the powder leveling part being used to smooth the powder spread on the printing platform to form a working surface; a first driving mechanism for driving the powder spreading device to move above the working surface; A powder feeding cylinder is arranged above the printing platform, the powder feeding cylinder is provided with a powder feeding port, the powder feeding port is provided with a second opening and closing mechanism, the second opening and closing mechanism of the powder feeding port is used to open or close the powder feeding port, and the powder feeding port is used to transport the powder in the powder feeding cylinder to the powder spreading cylinder; The first driving mechanism is used to drive the powder spreading device to move in a circumferential direction; The first driving mechanism includes a turntable and a first driving part for driving the turntable to rotate; the powder spreading device is rotatably connected to the turntable, and a third driving mechanism is provided on the turntable, and the third driving mechanism is used to drive the powder spreading device to rotate relative to the turntable so that the powder spreading device can be extended to the top of the printing platform or retracted from the top of the printing platform; The powder flattening portion is strip-shaped and horizontally parallel to the plane on the printing platform, and one end of the powder flattening portion away from the turntable is radially bent inward to form a hook-shaped powder collecting portion, and the powder collecting portion is used to collect excess powder on the working surface after the powder flattening portion smoothes the powder; The powder spreading device comprises two powder outlets, the two powder outlets are arranged at intervals in the moving direction of the powder spreading device, and the powder flattening portion is located between the two powder outlets.

2. The powder spreading system according to claim 1, characterized in that: The powder spreading device comprises two flat powder parts, the two flat powder parts are arranged at intervals in the moving direction of the powder spreading device, and the powder outlet is located between the two flat powder parts.

3. The powder spreading system according to claim 1, characterized in that: The powder outlet is provided with a first opening and closing mechanism, which includes a blocking member movably connected to the powder spreading cylinder and a second driving mechanism for driving the blocking member to open or close the powder outlet.

4. The powder spreading system according to claim 1, characterized in that: The powder spreading system comprises at least two powder feeding cylinders, and the powder feeding cylinders are fixedly arranged above the printing platform.

5. A 3D printer, characterized in that: It comprises the powder spreading system according to any one of claims 1 to 4.

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