3D printer

Abstract

The invention relates to the technical field of 3D printing, in particular to a 3D printer which comprises a machine shell, a driving device installed on the upper portion of the interior of the machine shell and a platform device installed at the bottom of the interior of the machine shell, a printing assembly is arranged in the middle of the driving device and comprises a spray head pipe, and an installation space is formed in the middle of the spray head pipe. The nozzle pipe is divided into a feeding part at the upper end and a discharging part at the lower end by the mounting space; a linkage device is arranged in the mounting space and comprises a motor, a first driving gear and a first gear ring, the motor is fixedly mounted on the side edge of the spray head pipe, the first driving gear is fixedly connected to the output end of the motor, and the first gear ring is rotationally mounted at the bottom end of the feeding part; and the first driving gear is in engaged connection with the first gear ring. The interior of the spray head pipe is emptied, the next material can be conveniently guided in, the switching speed of the materials of multiple colors is increased, and the printing efficiency is improved.

Description

Technical Field

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

[0002] 3D printers build three-dimensional objects by stacking materials layer by layer. The printer sprays or solidifies the material layer by layer from bottom to top according to the model data until the entire object is manufactured. It can quickly convert virtual three-dimensional models into actual objects.

[0003] The patent with publication number CN112959657B discloses a 3D printer, including a base frame, a plurality of vertical frames are arranged on the top of the base frame, the printing device includes a booster, a raw material pipe is slidably connected inside the booster, a heating chamber is arranged at the bottom of the booster, a flow chamber is connected at the bottom of the heating chamber, and a temperature sensor is arranged inside the flow chamber to detect the internal temperature. The above invention controls the current value of the electromagnet to change the gap between the heat-resistant magnetic ball and the nozzle, and changes the volume of the molten material flowing out of the nozzle, so that the desired shape and volume are obtained after cooling, and the printing effect is good and the printing accuracy is high.

[0004] During the 3D printing process, different objects may require the use of printing materials of different colors. During the printing process, there will be material residue inside the nozzle, which cannot be cleaned quickly. This results in the need to replace the nozzle to continue printing when changing different materials for printing, which affects the printing efficiency. Summary of the invention

[0005] The purpose of the present invention is to solve the problem in the prior art that different construction objects may require the use of printing materials of different colors. During the printing process, there will be material residues inside the nozzle, which cannot be quickly cleaned. This results in the need to replace the nozzle to continue printing when changing different materials for printing, which affects the printing efficiency. A 3D printer is proposed.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: A 3D printer, comprising: a housing, a driving device installed at the upper part of the housing, and a platform device installed at the bottom of the housing, wherein a printing assembly is arranged in the middle of the driving device, and the printing assembly comprises a nozzle tube, wherein an installation space is arranged in the middle of the nozzle tube, and the installation space separates the nozzle tube into a feeding part at the upper end and a discharging part at the lower end; A linkage device is arranged inside the installation space, and the linkage device comprises a motor, a first driving gear and a first gear ring. The motor is fixedly mounted on the side of the nozzle pipe, the first driving gear is fixedly connected to the output end of the motor, the first gear ring is rotatably mounted on the bottom end of the feeding part, and the first driving gear is meshed and connected with the first gear ring; A guide assembly is arranged on the inner side of the first gear ring, and the guide assembly includes a plurality of fixing plates and a plurality of guide plates. The plurality of fixing plates are annularly fixedly connected to the inner side of the first gear ring, the plurality of guide plates are fixedly connected to the sides of the plurality of fixing plates, and the guide plates are arranged obliquely.

[0007] Preferably, the driving device comprises two sliding rods, two sliding modules and a threaded rod, the two sliding rods are symmetrically fixedly mounted on the inner side of the casing, the two sliding modules are respectively slidably arranged on the two sliding rods, and the threaded rod is rotatably mounted between the two sliding modules.

[0008] Preferably, the printing assembly further comprises a driving block and a discharge end head, wherein the driving block is threadedly sleeved on the threaded rod for driving the nozzle tube to move, and the discharge end head is installed at the discharge portion of the nozzle tube for guiding the spray material.

[0009] Preferably, the linkage device also includes a second drive gear and a second gear ring, the second drive gear is fixedly connected to the output end of the motor, and the first drive gear is located between the second drive gear and the motor, the second gear ring is rotatably installed on the upper end of the discharge part and is rotatably connected to the first gear ring, and the second drive gear is meshingly connected to the second gear ring.

[0010] Preferably, the diameter of the first driving gear is smaller than that of the second driving gear, the diameter of the first gear ring is larger than that of the second gear ring, and during the motor driving process, the rotation speed of the first gear ring is lower than the rotation speed of the second gear ring.

[0011] Preferably, the guide plate is an arc-shaped plate arranged at an angle, and a plurality of guide plates form a guide wheel. The length of the guide wheel is consistent with the internal space of the nozzle pipe. The diameter of the feed port at the upper end of the guide wheel is larger than the diameter of the discharge port at the lower end, so as to drive the material to rotate while the material is normally introduced.

[0012] Preferably, a heat dissipation component is provided on the second gear ring, and the heat dissipation component is used to dissipate heat and cool the discharge part. The heat dissipation component includes multiple blades and a protective cover. The cross-section of the second gear ring is 7-shaped, and the multiple blades are annularly arranged on the vertical surface of the second gear ring. When the multiple blades rotate, air flow from top to bottom is generated. The protective cover is fixedly installed on the side of the nozzle pipe to protect the motor and blades, and an air guide port is opened on the protective cover.

[0013] Preferably, the discharge port at the bottom end of the nozzle tube is set to be an inverted truncated cone shape, and two air inlets are symmetrically opened at the bottom of the nozzle tube. Two air guide plates are rotatably installed inside the air inlet, and the air guide plates are used to guide wind to the nozzle tube.

[0014] Preferably, a plurality of bubble breaking openings are evenly formed on the guide vane, and the bubble breaking openings are truncated cone-shaped openings. During the rotation of the guide vane, the material moves from the side with the larger bottom area of ​​the bubble breaking opening to the other side.

[0015] Preferably, a scraper is fixedly connected to one side of the guide plate close to the inner wall of the nozzle tube, and both sides of the scraper are arranged as inclined sides for scraping the inner walls of the nozzle tube and the discharge end.

[0016] Compared with the prior art, the present invention has the following beneficial effects: Multiple guide vanes will rotate in the same direction, thereby forming a rotation of the molten material inside the nozzle tube. Such rotation will form a downward movement trend of the molten material, so that the molten material can be quickly discharged from the inside of the nozzle tube. After one material is printed, the upper feed end is disconnected, and the material inside the nozzle tube can be quickly discharged through the rotating guide vanes, and the inside of the nozzle tube is emptied, which facilitates the introduction of the next material, improves the speed of switching between multiple color materials, and improves the printing efficiency; by setting multiple gears on one motor, different rotation speeds can be achieved to meet different needs, which not only reduces the use of energy and simplifies the overall structure, but also ensures the realization of multiple effects and improves the effect of 3D printing; multiple guide vanes will stir the molten material during the rotation process, and stir and melt the material previously solidified inside the nozzle tube during the stirring process, thereby avoiding the solidification of the material and the inability to stably discharge it. At the same time, stirring the material also reduces the situation where the material is not completely melted due to the temperature drop; the second gear ring drives multiple The blades rotate to form air flow. When cooling is required, a water cooling box can be added to the driving block to guide the cold air. The blades guide the cold air to the discharge part of the nozzle tube and the surface of the material. First, the discharged material can be quickly cooled and shaped to avoid deformation of the shaped material caused by the high-temperature material. Second, the nozzle tube that has been working for a long time can be cooled down so that the nozzle tube can work for a long time under the inclination to ensure the effect. By arranging multiple bubble breaking ports on the guide plate, during the rotation of the guide plate, the bubbles will contact the guide plate, and the bubbles will enter from the large mouth of the bubble breaking port. The bubbles are squeezed and broken, so that the bubbles are defoamed, the bubbles inside the molding material are reduced, and the molding of the material is ensured. The rotating scraper will scrape the inner wall of the nozzle tube, so as to separate the solidified material from the inner wall of the nozzle tube, and re-mix the solidified material for hot melting. At the same time, after the spraying is completed, the material remaining on the inner wall of the nozzle tube will be scraped by the inclined scraper, so as to reduce the material remaining inside the nozzle tube and avoid solidification of the material. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 This is a schematic diagram of the front structure of a 3D printer proposed by the present invention; Figure 2This is a schematic diagram of the structure of a 3D printer proposed by the present invention when viewed from above; Figure 3 A schematic diagram of the structure of a driving device of a 3D printer proposed by the present invention; Figure 4 A schematic diagram of the printing component structure of a 3D printer proposed by the present invention; Figure 5 A schematic diagram of the nozzle tube structure of a 3D printer proposed by the present invention; Figure 6 A cross-sectional view of the internal structure of a nozzle tube of a 3D printer proposed by the present invention; Figure 7 A schematic diagram of the linkage structure of a 3D printer proposed by the present invention; Figure 8 This is a schematic diagram of the expanded structure of a linkage device of a 3D printer proposed by the present invention; Fig. 9 A schematic diagram of the structure of a flow guide assembly of a 3D printer proposed by the present invention; Fig.10 This is a schematic diagram of the scraper structure of a 3D printer proposed by the present invention.

[0017] In the figure: 1. casing; 2. driving device; 21. sliding rod; 22. sliding module; 23. threaded rod; 3. printing assembly; 31. nozzle tube; 32. driving block; 33. discharge end; 4. linkage device; 41. motor; 42. first driving gear; 43. first gear ring; 44. second driving gear; 45. second gear ring; 5. guide assembly; 51. fixing plate; 52. guide plate; 6. heat dissipation assembly; 61. blade; 62. protective cover; 7. bubble breaking port; 8. scraper; 9. platform device; 10. air guide plate. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0019] The terms such as "upper", "lower", "left", "right", "middle" and "one" used in the present invention are only for the convenience of description and are not used to limit the scope of the present invention. Changes or adjustments to their relative relationships should be regarded as the scope of the present invention without substantially changing the technical content.

[0020] Reference Figure 1-Figure 10A 3D printer comprises: a housing 1, a driving device 2 installed at the upper part of the housing 1 and a platform device 9 installed at the bottom of the housing 1, a printing assembly 3 is arranged in the middle of the driving device 2, the printing assembly 3 comprises a nozzle tube 31, an installation space is arranged in the middle of the nozzle tube 31, and the installation space separates the nozzle tube 31 into a feeding part at the upper end and a discharging part at the lower end; A linkage device 4 is arranged inside the installation space, and the linkage device 4 comprises a motor 41, a first driving gear 42 and a first gear ring 43. The motor 41 is fixedly mounted on the side of the nozzle pipe 31, the first driving gear 42 is fixedly connected to the output end of the motor 41, and the first gear ring 43 is rotatably mounted on the bottom end of the feeding part, and the first driving gear 42 is meshed and connected with the first gear ring 43; A guide assembly 5 is arranged on the inner side of the first gear ring 43, and the guide assembly 5 includes a plurality of fixing plates 51 and a plurality of guide plates 52. The plurality of fixing plates 51 are annularly fixedly connected to the inner side of the first gear ring 43, and the plurality of guide plates 52 are fixedly connected to the sides of the plurality of fixing plates 51, and the guide plates 52 are arranged obliquely.

[0021] In an embodiment of the application of the above technical solution, during the process of printing and exporting the molten material, the motor 41 is started, and the first drive gear 42 is driven to rotate by the motor 41, and the first drive gear 42 drives the first gear ring 43 to rotate, and the multiple guide plates 52 fixedly connected to the first gear ring 43 will rotate in the same direction, thereby forming a rotation of the molten material inside the nozzle tube 31. Such rotation will form a downward movement trend of the molten material, so that the molten material can be quickly exported from the inside of the nozzle tube 31. After one material is printed, the upper feed end is disconnected, and the material inside the nozzle tube 31 can be quickly exported through the rotating guide plate 52, and the inside of the nozzle tube 31 is emptied, which facilitates the introduction of the next material, improves the speed of switching between multiple color materials, and improves printing efficiency.

[0022] The preferred technical solution in this embodiment is: Reference Figure 3-6 The driving device 2 includes two sliding rods 21, two sliding modules 22 and a threaded rod 23. The two sliding rods 21 are symmetrically fixedly mounted on the inner side of the housing 1. The two sliding modules 22 are respectively slidably arranged on the two sliding rods 21. The threaded rod 23 is rotatably mounted between the two sliding modules 22. The printing assembly 3 further includes a driving block 32 and a discharge end 33. The driving block 32 is threadedly sleeved on the threaded rod 23 to drive the nozzle tube 31 to move. The discharge end 33 is installed at the discharge part of the nozzle tube 31 to guide the spray material.

[0023] The sliding module 22 moves on the sliding rod 21, thereby driving the longitudinal movement of the driving block 32. At the same time, the driving block 32 is set on the threaded rod 23. The threaded rod 23 rotates to drive the lateral movement of the driving block 32. The entire driving device 2 can quickly adjust the position of the discharge end 33, so that 3D printing processing can be quickly performed.

[0024] The discharge end 33 can be disassembled and installed, and the diameter and material of the discharge end 33 can be selected according to the molten materials of different materials to meet the printing requirements.

[0025] Reference Figure 6-8 The linkage device further includes a second driving gear 44 and a second gear ring 45, wherein the second driving gear 44 is fixedly connected to the output end of the motor 41, and the first driving gear 42 is located between the second driving gear 44 and the motor 41, and the second gear ring 45 is rotatably mounted on the upper end of the discharge portion and is rotatably connected to the first gear ring 43, and the second driving gear 44 is meshedly connected to the second gear ring 45; The diameter of the first driving gear 42 is smaller than that of the second driving gear 44 , and the diameter of the first gear ring 43 is larger than that of the second gear ring 45 . During the driving process of the motor 41 , the rotation speed of the first gear ring 43 is lower than that of the second gear ring 45 .

[0026] The first driving gear 42 and the second driving gear 44 are controlled by the motor 41 to rotate synchronously, and multiple execution units can be driven simultaneously by a fixed energy source, which not only reduces the volume of the overall structure, but also reduces energy consumption.

[0027] By providing a first driving gear 42 with a smaller diameter and a first gear ring 43 with a larger diameter, the motor 41 can drive the first gear ring 43 to rotate at a slower speed under a fixed rotation speed, so that the guide component 5 inside the first gear ring 43 stirs and guides the molten material inside, thereby accelerating the material discharge speed.

[0028] A second driving gear 44 with a larger diameter and a second gear ring 45 with a smaller diameter are provided at the same time. When the motor 41 rotates, the second gear ring 45 can be driven to rotate at a faster speed, and the heat dissipation component 6 can be driven to rotate, thereby performing heat dissipation processing.

[0029] By providing a plurality of gears on a motor 41, different rotation speeds can be achieved to meet different requirements, which not only reduces the use of energy and simplifies the overall structure, but also ensures the realization of multiple effects and improves the effect of 3D printing.

[0030] Reference Figure 6The guide plate 52 is an arc-shaped plate arranged obliquely, and a plurality of guide plates 52 form a guide wheel. The length of the guide wheel is consistent with the internal space of the nozzle pipe 31. The diameter of the feed port at the upper end of the guide wheel is larger than the diameter of the discharge port at the lower end, which is used to drive the material to rotate while the material is normally introduced.

[0031] The multiple guide vanes 52 will rotate with the first gear ring 43. The multiple guide vanes 52 will stir the molten material during the rotation. During the stirring process, the material previously solidified inside the nozzle tube 31 will be stirred and hot-melted, thereby preventing the material from solidifying and being unable to be stably discharged. At the same time, stirring the material also reduces the situation where the material is not completely melted due to the temperature drop.

[0032] The rotating guide plate 52 will form a guide wheel, and the rotating guide wheel will drive the molten material to form a guide from top to bottom. Due to the different flow speeds of different molten materials, the extrusion force of some materials will be blocked by the inner wall of the nozzle tube 31 during the extrusion process, resulting in a slower flow speed of the molten material. The rotating guide wheel can make the molten material form a rotating flow, reducing the obstruction of the material by the inner wall of the nozzle tube 31, and can quickly export materials with different densities, thereby ensuring the efficiency of 3D printing, and also ensuring that after printing is completed, the residual material inside the nozzle tube 31 is quickly emptied.

[0033] Reference Figure 7-8 The second gear ring 45 is provided with a heat dissipation component 6, and the heat dissipation component 6 is used to dissipate heat and cool the discharge part; The heat dissipation assembly 6 includes a plurality of blades 61 and a protective cover 62. The cross-section of the second gear ring 45 is 7-shaped. The plurality of blades 61 are arranged in a ring shape on the vertical surface of the second gear ring 45. When the plurality of blades 61 rotate, air flow from top to bottom is generated. The protective cover 62 is fixedly installed on the side of the nozzle pipe 31 to protect the motor 41 and the blades 61. An air guide port is opened on the protective cover 62.

[0034] The outlet at the bottom of the nozzle tube 31 is set to be an inverted truncated cone. Two air inlets are symmetrically opened at the bottom of the nozzle tube 31. Two air guide plates 10 are rotatably installed inside the air inlet. The air guide plates 10 are used to guide the wind to the outlet end 33.

[0035] When the printing material is formed on the platform device 9, the molten material cools down too slowly on the platform device 9, which will cause the temperature of the previously solidified part to rise or even deform, and will also affect the subsequent cooling and shaping process of the material. At the same time, long-term continuous printing may cause the nozzle tube 31 to be continuously heated, increasing the possibility of material accumulation and clogging inside the nozzle.

[0036] The second gear ring 45 drives multiple blades 61 to rotate, thereby forming air flow. When cooling is required, a water cooling box can be added to the driving block 32 to guide the cold air. The blades 61 guide the cold air to the discharge part and material surface of the nozzle tube 31. First, the discharged material can be quickly cooled and shaped, avoiding deformation of the shaped material caused by the high-temperature material. Second, the nozzle tube 31 that has been working for a long time can be cooled down, so that the nozzle tube 31 can work for a long time while ensuring the effect.

[0037] The air guide plate 10 is controlled to rotate by an electric shaft. When the nozzle tube 31 works for a long time, causing the temperature of the discharge terminal 33 to be too high, affecting the discharge of the material, the air guide plate 10 is controlled to open, and part of the cold air is introduced between the nozzle tube 31 and the discharge terminal 33. There is a gap between the nozzle tube 31 and the discharge terminal 33, so that the cold air can quickly transfer heat, reduce the temperature at the discharge terminal 33, and ensure the discharge of the molten material.

[0038] The heat dissipation structure in the device is close to the discharging part, which reduces the sudden drop in wind force during the cooling process, ensures the cooling effect, and reduces energy consumption.

[0039] Reference Figure 9-10 The guide plate 52 is evenly provided with a plurality of bubble breaking openings 7, and the bubble breaking openings 7 are truncated cone-shaped openings. During the rotation of the guide plate 52, the material moves from the side of the bubble breaking opening 7 with a larger bottom area to the other side.

[0040] Since there will be some impurities inside the molten material, these impurities melt under high temperature and may form bubbles inside the molten material. These bubbles will affect the molding of the printed material and cause voids to form inside the molded material, affecting the printing effect. In order to ensure the printing molding, a plurality of bubble breaking ports 7 are provided on the guide plate 52. During the rotation of the guide plate 52, the bubbles will contact the guide plate 52. The guide plate 52 blocks the bubbles and drives the bubbles to move upward. At the same time, the bubbles enter from the large mouth of the bubble breaking port 7. The bubbles are squeezed and broken, thereby defoaming the bubbles, reducing the bubbles inside the molding material and ensuring the molding of the material.

[0041] Reference Fig.10 A scraper 8 is fixedly connected to one side of the guide plate 52 close to the inner wall of the nozzle tube 31 , and both sides of the scraper 8 are arranged as inclined sides for scraping the inner walls of the nozzle tube 31 and the discharge end 33 .

[0042] After printing is completed, there will be molten material remaining inside the nozzle tube 31, which will cause the material to solidify inside the nozzle tube 31, resulting in a reduction in the lead-out area inside the nozzle tube 31, affecting the normal lead-out of the molten material.

[0043] When the motor 41 starts and drives the first gear ring 43 to rotate, the scraper 8 connected to the guide plate 52 will rotate accordingly. At the beginning of rotation, the rotating scraper 8 will scrape the inner wall of the nozzle tube 31, thereby separating the solidified material from the inner wall of the nozzle tube 31, and re-mixing and hot-melting the solidified material. At the same time, after the spraying is completed, the scraper 8 set obliquely will also scrape the residual material on the inner wall of the nozzle tube 31, thereby reducing the residual material inside the nozzle tube 31 and improving the effect of guiding and cleaning the inside of the nozzle tube 31.

[0044] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A 3D printer, comprising: A casing (1), a driving device (2) installed at the upper part of the casing (1), and a platform device (9) installed at the bottom of the casing (1), characterized in that a printing assembly (3) is arranged in the middle of the driving device (2), the printing assembly (3) comprises a nozzle tube (31), an installation space is arranged in the middle of the nozzle tube (31), and the installation space divides the nozzle tube (31) into an upper feeding portion and a lower discharging portion; A linkage device (4) is arranged inside the installation space, and the linkage device (4) comprises a motor (41), a first driving gear (42) and a first gear ring (43); the motor (41) is fixedly mounted on the side of the nozzle pipe (31); the first driving gear (42) is fixedly connected to the output end of the motor (41); the first gear ring (43) is rotatably mounted on the bottom end of the feeding part; the first driving gear (42) is meshingly connected with the first gear ring (43); A flow guide assembly (5) is arranged on the inner side of the first gear ring (43), and the flow guide assembly (5) comprises a plurality of fixing plates (51) and a plurality of guide plates (52), wherein the plurality of fixing plates (51) are annularly fixedly connected to the inner side of the first gear ring (43), and the plurality of guide plates (52) are fixedly connected to the sides of the plurality of fixing plates (51), and the guide plates (52) are arranged obliquely.

2. A 3D printer according to claim 1, characterized in that: The driving device (2) comprises two sliding rods (21), two sliding modules (22) and a threaded rod (23); the two sliding rods (21) are symmetrically fixedly mounted on the inner side of the housing (1); the two sliding modules (22) are respectively slidably mounted on the two sliding rods (21); and the threaded rod (23) is rotatably mounted between the two sliding modules (22).

3. A 3D printer according to claim 1, characterized in that: The printing assembly (3) further comprises a driving block (32) and a discharge end head (33); the driving block (32) is threadedly sleeved on the threaded rod (23) and is used to drive the nozzle tube (31) to move; the discharge end head (33) is installed at the discharge portion of the nozzle tube (31) and is used to discharge the sprayed material.

4. A 3D printer according to claim 1, characterized in that: The linkage device (4) further comprises a second driving gear (44) and a second gear ring (45); the second driving gear (44) is fixedly connected to the output end of the motor (41); the first driving gear (42) is located between the second driving gear (44) and the motor (41); the second gear ring (45) is rotatably mounted on the upper end of the discharge portion and is rotatably connected to the first gear ring (43); the second driving gear (44) is meshingly connected to the second gear ring (45).

5. A 3D printer according to claim 4, characterized in that: The diameter of the first driving gear (42) is smaller than that of the second driving gear (44), the diameter of the first gear ring (43) is larger than that of the second gear ring (45), and during the driving process of the motor (41), the rotation speed of the first gear ring (43) is lower than that of the second gear ring (45).

6. A 3D printer according to claim 1, characterized in that: The guide plate (52) is an arc-shaped plate arranged obliquely, and a plurality of guide plates (52) form a guide wheel. The length of the guide wheel is consistent with the internal space of the nozzle pipe (31). The diameter of the feed port at the upper end of the guide wheel is larger than the diameter of the discharge port at the lower end, and is used to drive the material to rotate while the material is normally introduced.

7. A 3D printer according to claim 4, characterized in that: The second gear ring (45) is provided with a heat dissipation component (6), the heat dissipation component (6) is used to dissipate heat and cool the discharge portion, the heat dissipation component (6) comprises a plurality of blades (61) and a protective cover (62), the second gear ring (45) has a 7-shaped cross section, the plurality of blades (61) are arranged in a ring shape on a vertical surface of the second gear ring (45), and the plurality of blades (61) generate air flow from top to bottom when the plurality of blades (61) rotate, the protective cover (62) is fixedly mounted on the side of the nozzle pipe (31) and is used to protect the motor (41) and the blades (61), and an air guide port is provided on the protective cover (62).

8. A 3D printer according to claim 7, characterized in that: The discharge port at the bottom end of the nozzle pipe (31) is arranged in an inverted truncated cone shape. Two air inlets are symmetrically provided at the bottom of the nozzle pipe (31). Two air guide plates (10) are rotatably mounted inside the air inlets. The air guide plates are used to guide air to the discharge end (33).

9. A 3D printer according to claim 1, characterized in that: The guide plate (52) is evenly provided with a plurality of bubble breaking openings (7), the bubble breaking openings (7) being truncated cone-shaped openings, and during the rotation of the guide plate (52), the material moves from one side of the bubble breaking opening (7) with a larger bottom area to the other side.

10. A 3D printer according to claim 1, characterized in that: A scraper (8) is fixedly connected to one side of the guide plate (52) close to the inner wall of the nozzle tube (31), and both sides of the scraper (8) are arranged as inclined side edges for scraping the inner walls of the nozzle tube (31) and the discharge end (33).

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