Spray head assembly for 3D printer and 3D printer

Abstract

The invention relates to the technical field of 3D printers, in particular to a spray head assembly for a 3D printer and the 3D printer. The spray head assembly comprises a plurality of feeding pipes, a nozzle module and a movable part, each feeding pipe is provided with an inlet hole, and the inlet holes are used for receiving consumables in a solid state form; the nozzle module is provided with an outlet hole, the inlet hole corresponding to each feeding pipe is communicated with the outlet hole, the outlet hole is used for extruding consumables in a liquid form, and the outlet hole is smaller than the inlet hole; and the movable part can selectively move relative to the nozzle module, and the movable part is used for preventing liquid consumables from flowing back to the feeding pipe from the nozzle module. The multi-inlet and one-outlet nozzle assembly aims at solving the problem that liquid consumables flow back in an existing multi-inlet and one-outlet nozzle assembly.

Description

Technical Field

[0001] This invention relates to the field of 3D printer technology, and more particularly to a nozzle assembly for a 3D printer and a 3D printer. Background Technology

[0002] To achieve multi-color / multi-material printing, Fused Deposition Modeling (FDM) 3D printers generally employ several solutions. One approach involves multiple nozzles, each corresponding to a specific color or type of filament. By continuously switching between nozzles, multiple colors of the model can be printed. Another approach is to cut the filament and re-feed new filament of different colors to achieve multi-color printing. Both of these solutions are either costly or time-consuming and wasteful of materials.

[0003] In related technologies, a multi-input, single-output scheme is used to achieve printing of multiple colors of consumables. However, when multiple colors of liquid consumables enter the printhead, backflow is prone to occur, affecting the quality of multi-color printing. Summary of the Invention

[0004] The main objective of this invention is to propose a nozzle assembly and a 3D printer that aims to solve the problem of liquid consumable backflow in existing multi-inlet, single-outlet nozzle assemblies.

[0005] To address the above problems, this invention proposes a nozzle assembly for a 3D printer, the nozzle assembly comprising: Multiple feed tubes, each feed tube having an inlet hole for receiving consumables in solid form; A nozzle module having an outlet orifice, wherein the inlet orifice corresponding to each feed tube is connected to the outlet orifice, the outlet orifice being used to extrude consumables in liquid form, wherein the outlet orifice is smaller than the inlet orifice; A movable component, which is selectively movable relative to the nozzle module, is used to prevent liquid consumables from flowing back from the nozzle module to the feed pipe.

[0006] In one embodiment, the movable component has a shape including spherical, elliptical, conical, and cylindrical, and the external dimensions of the movable component are larger than the inner diameter of the feed pipe; or, the movable component is a one-way valve.

[0007] In one embodiment, the movable component can selectively move toward a side closer to or away from the feed tube. When the movable component moves toward a side closer to the feed tube, it can block the feed tube to prevent liquid consumables from flowing back from the nozzle module into the feed tube.

[0008] In one embodiment, the nozzle module includes a connector and a nozzle, the nozzle having the outlet orifice, the connector for connecting the feed pipe and the nozzle, a receiving cavity being formed between the connector and the nozzle, and the movable part being disposed within the receiving cavity.

[0009] In one embodiment, the connector and the nozzle are interference-fitted, or the connector and the nozzle are connected by screws, or the connector and the nozzle are welded, or the connector and the nozzle are riveted, or the connector and the nozzle are threaded.

[0010] In one embodiment, the connector includes a first part and a second part that are connected. The first part is fixedly connected to the feed pipe and is provided with a plurality of limiting channels. One feed pipe is connected to one of the limiting channels. The second part is fixedly connected to the nozzle and is connected to the outlet hole of the nozzle.

[0011] In one embodiment, the second part and the nozzle are interference-fitted, or the second part and the nozzle are connected by screws, or the second part and the nozzle are welded, or the second part and the nozzle are riveted, or the second part and the nozzle are threaded.

[0012] In one embodiment, the feed tube includes a first section and a second section connected together. The outer diameter of the first section is larger than that of the second section. The first section is exposed outside the connector, and the second section extends into the limiting channel and is fixedly connected to the first section.

[0013] In one embodiment, the second part is provided with a plurality of receiving areas, the plurality of receiving areas constitute the receiving cavity, one receiving area is connected to one limiting channel, the radial dimension of the receiving area is larger than the inner diameter dimension of the limiting channel, and the movable component is movably disposed within the receiving area.

[0014] In one embodiment, the receiving area and the limiting channel are connected by a tapered surface.

[0015] In one embodiment, the movable component includes a plurality of movable parts, one of which is disposed in one of the receiving areas. The movable part can selectively move toward a side closer to or away from the limiting channel within the receiving area. When the movable part moves toward a side closer to the limiting channel, it can block the limiting channel to prevent liquid consumables from flowing back from the nozzle to the limiting channel.

[0016] In one embodiment, the nozzle is provided with multiple storage areas and multiple discharge ports, one storage area is connected to one discharge port, the multiple discharge ports are all connected to the outlet hole, the storage area is connected to the receiving cavity, and the movable component can selectively move toward the side of the storage area that is closer to or farther away from the nozzle.

[0017] In one embodiment, the inlet hole, the receiving cavity, and the storage area are connected along a first straight line, and the storage area, the discharge port, and the outlet hole are connected along a second straight line, wherein the second straight line is inclined relative to the first straight line.

[0018] In one embodiment, the bottom walls of the plurality of storage zones are inclined toward the discharge port.

[0019] In one embodiment, the plurality of feed tubes are arranged in a straight line, or the plurality of feed tubes are arranged in a uniform circular pattern around the periphery of the nozzle module.

[0020] In one embodiment, the number of outlet holes is 1, and the number of feed pipes is 2, 3, 4, 5, 6, or 8.

[0021] The present invention also proposes a 3D printer comprising an extruder and a nozzle assembly as described above, the extruder being used to deliver solid-form consumables into the inlet orifice of the feed tube.

[0022] This invention proposes a nozzle assembly for a 3D printer. The nozzle assembly includes multiple feed tubes, each of which can supply a type of filament. During printing, filament enters at least one feed tube and flows out through the outlet hole of the nozzle module. Since the inlet hole of each feed tube is connected to the outlet hole of the nozzle module, and different feed tubes are also connected through the nozzle module, when filament is fed into a certain feed tube for printing, a moving part moves relative to the nozzle module to selectively block other feed tubes and disconnect the connection between other feed tubes and the nozzle module. This prevents filament from flowing back into other feed tubes through the nozzle module, thereby ensuring the extrusion quality of the filament and improving the reliability and stability of filament switching. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the structure of an embodiment of the nozzle assembly of the present invention; Figure 2 This is an exploded structural diagram of an embodiment of the nozzle assembly of the present invention; Figure 3 This is a cross-sectional structural diagram of an embodiment of the nozzle assembly of the present invention; Figure 4 This is a schematic diagram of the structure of an embodiment of the connector of the present invention; Figure 5 This is a schematic diagram of the structure of an embodiment of the nozzle of the present invention; Figure 6 This is another structural schematic diagram of an embodiment of the nozzle of the present invention; Figure 7 This is a schematic diagram of the structure of the first embodiment of the nozzle and moving part combination of the present invention; Figure 8 for Figure 7 A perspective structural diagram; Figure 9 This is a schematic diagram of the structure of the second embodiment of the nozzle and moving part combination of the present invention; Figure 10 This is a schematic diagram of the third embodiment of the nozzle and moving part combination of the present invention; Figure 11 This is a schematic diagram of the fourth embodiment of the nozzle and moving part combination of the present invention; Figure 12 This is a schematic diagram of the fifth embodiment of the nozzle and moving part combination of the present invention; Figure 13 This is a schematic diagram of the sixth embodiment of the nozzle and moving part combination of the present invention.

[0025] Explanation of icon numbers: 100. Nozzle assembly; 1. Feed pipe; 11. First section; 111. Inlet hole; 12. Second section; 2. Nozzle module; 21. Connector; 211. First part; 2111. Limiting channel; 212. Second part; 2121. Conical surface; 22. Nozzle; 221. Outlet hole; 222. Storage area; 2221. Bottom wall; 223. Discharge port; 23. Receiving cavity; 231. Receiving area; 3. Moving parts; 31. Moving parts; Detailed Implementation The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0026] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0027] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0028] In related technologies, a multi-input, single-output scheme is used to achieve printing of multiple colors of consumables. However, when multiple colors of liquid consumables enter the printhead, backflow is prone to occur, affecting the quality of multi-color printing.

[0029] To solve the above problems, please refer to the following: Figures 1 to 8 As shown, the present invention proposes a nozzle assembly 100 for a 3D printer. The nozzle assembly 100 includes multiple feed tubes 1, a nozzle module 2, and a movable part 3. Each feed tube 1 has an inlet hole 111 for receiving consumables in solid form. The nozzle module 2 has an outlet hole 221, and the inlet hole 111 of each feed tube 1 is connected to the outlet hole 221. The outlet hole 221 is used to extrude consumables in liquid form, wherein the outlet hole 221 is smaller than the inlet hole 111. The movable part 3 can selectively move relative to the nozzle module 2, and the movable part 3 is used to prevent liquid consumables from flowing back from the nozzle module 2 to the feed tubes 1.

[0030] The types of consumables can include PLA (polylactic acid), ABS, PETG, TPU, TPE, nylon (PA), PC, ASA, PP, etc.

[0031] Specifically, during the 3D printing process, the filament enters in solid form through the inlet hole 111 of the feed pipe 1, and after being heated and melted, it is extruded in liquid form through the outlet hole 221 of the nozzle module 2. In this embodiment, the feed pipe 1 includes multiple feed pipes, each of which can supply one type of filament. During printing, at least one feed pipe 1 receives filament, which flows out through the nozzle module 2. When switching filaments, it is only necessary to stop the filament feeding of the current feed pipe 1 and switch to the filament feeding of another feed pipe 1. This allows for the switching of multiple filaments to facilitate multi-color printing. Furthermore, since the filament before and after switching flows out through the same outlet hole 221 of the nozzle module 2, there is no need to recalibrate the Z-axis position of the nozzle module 2 when switching filaments, effectively improving printing efficiency and reliability. The Z-axis position is as follows: Figure 1 The direction indicated by the middle arrow.

[0032] In this embodiment, multiple feed tubes 1 are arranged in an array, which facilitates the orderly arrangement and feeding of consumables, while reducing the difficulty of connecting the inlet hole 111 of the feed tube 1 with the outlet hole 221 of the nozzle module 2, thus simplifying the setup of the nozzle module 2. The outlet hole 221 of the nozzle module 2 is smaller than the inlet hole 111 of the feed tube, allowing the molten liquid consumables to flow out continuously and stably, ensuring printing quality.

[0033] Understandably, since the inlet hole 111 of each feed pipe 1 is connected to the outlet hole 221 of the nozzle module 2, and different feed pipes 1 are also connected through the nozzle module 2, when the consumables in a certain feed pipe 1 are being fed normally, the liquid consumables will not only flow out from the outlet hole 221 of the nozzle module 2, but may also flow back into other feed pipes 1 through the nozzle module 2, resulting in unqualified consumable extrusion quality and possible color mixing or blockage when switching consumables. Therefore, the printhead assembly 100 also includes a movable part 3, which can selectively move relative to the nozzle module 2. When a consumable is fed into a certain feed pipe 1 for printing, the solid consumable is heated into a liquid consumable. At this time, a local hydraulic pressure is formed in the nozzle module 2. Under the action of the hydraulic pressure, the movable part 3 will move relative to the nozzle module 2 to selectively block other feed pipes 1 and disconnect the connection between other feed pipes 1 and the nozzle module 2, so as to prevent the consumable from flowing back into other feed pipes 1 through the nozzle module 2, thereby ensuring the extrusion quality of the consumable and improving the reliability and stability of switching consumables.

[0034] In practical implementation, the nozzle assembly 100 can be used in conjunction with a wire feeding mechanism. Each feed tube 1 is equipped with a corresponding wire feeding mechanism to provide power for the movement of consumables within the feed tube 1. The wire feeding mechanism operates independently to specifically control the feeding of consumables within the corresponding feed tube 1. A heating element can be installed on the outside of the nozzle module 2 to heat the consumables, causing the solid consumables to melt into liquid consumables. The wire feeding mechanism can be a material box or a material rack. The heating element can be a ceramic heating ring or a heating plate.

[0035] In one embodiment of the present invention, such as Figure 2 , Figure 3 , Figures 7 to 13 As shown, the shape of the movable part 3 includes spherical, elliptical, conical, and cylindrical shapes, and the external dimensions of the movable part 3 are larger than the inner diameter of the feed pipe 1. The shape of the movable part 3 can also be a combination of spherical, conical, and cylindrical shapes or other shapes.

[0036] The movable component 3, with its spherical, conical, or cylindrical shape, can better abut against the edge of the feed tube 1, ensuring effective clogging and preventing backflow of liquid consumables from the nozzle module 2 through the gap between the movable component 3 and the feed tube 1. Furthermore, the spherical, conical, and cylindrical shape of the movable component 3 reduces resistance during movement relative to the nozzle module 2, improving the reliability of clogging the feed tube 1. When the movable component 3 is spherical or conical, it can partially extend into the feed tube 1, further enhancing the clogging effect. The external dimensions of the movable component 3 are larger than the internal diameter of the feed tube 1 to ensure complete clogging.

[0037] In another embodiment, the movable component 3 is a one-way valve. The one-way valve allows passage in the direction of feeding through the feed pipe 1; when the consumable enters the nozzle module 2 from the feed pipe 1, the heated and melted liquid consumable can successfully pass through the one-way valve, but the heated and melted liquid consumable cannot flow back from the nozzle module 2 to the feed pipe 1 through the one-way valve.

[0038] In one embodiment of the present invention, such as Figure 3 As shown, the movable part 3 can selectively move toward the side closer to or away from the feed pipe 1. When the movable part 3 moves toward the side closer to the feed pipe 1, the movable part 3 can block the feed pipe 1 to prevent liquid consumables from flowing back from the nozzle module 2 to the feed pipe 1.

[0039] Specifically, when material is fed into a certain feed pipe 1, the consumable material inside the feed pipe 1 moves towards the nozzle module 2 under the action of external force. The liquid consumable material exerts a force away from the feed pipe 1 on the moving part 3 of the feed pipe 1 to prevent the moving part 3 from blocking the feed pipe 1, so that the liquid consumable material can enter the nozzle module 2 normally and flow out from the outlet hole 221 of the nozzle module 2. At the same time, during the printing process, the liquid consumable material continuously accumulates in the nozzle module 2, and under the action of hydraulic pressure, exerts a force close to the feed pipe 1 on other parts of the moving part 3, so that the moving part 3 blocks other feed pipes 1, preventing the consumable material in the nozzle module 2 from flowing back into other feed pipes 1.

[0040] Understandably, during actual printing, the nozzle module 2 is usually located below the feed tube 1. The movable part 3, under the influence of gravity, automatically moves away from the feed tube 1. At this time, the movable part 3 does not block the feed tube 1, and all feed tubes 1 are in a connected state to the nozzle module 2. During the flow of liquid consumables into the nozzle module 2, because the outlet orifice 221 is smaller than the inlet orifice 111, the liquid consumables accumulated in the nozzle module 2 create hydraulic pressure that exerts a force on the movable part 3, causing it to move towards the side closer to the feed tube 1, thus blocking it. At this time, for the feed tube 1 that is currently feeding, due to the external force causing the consumables to move towards the nozzle module 2, the liquid consumables flowing from the feed tube 1 into the nozzle module 2 continuously impact the portion of the movable part 3 corresponding to the feed tube 1 in a direction away from the feed tube 1. This allows the movable part 3 to overcome the pressure exerted by the accumulated consumables and maintain the open position of the feed tube 1, thus allowing the consumables in the feed tube 1 to enter the nozzle module 2 normally. Therefore, when consumables are fed into a certain feed pipe 1, that feed pipe 1 will be in a connected state connected to the nozzle module 2, while the other feed pipes 1 that are not fed will be in a blocked state disconnected from the nozzle module 2.

[0041] In this embodiment, the moving part 3 does not require an additional drive mechanism. During printing by the printhead assembly 100, it automatically selects and blocks the feed tube 1 that has not been fed. This greatly reduces the cost of setting up the anti-backflow structure for the feed tube 1 and improves the reliability of the printhead assembly 100.

[0042] In one embodiment of the present invention, such as Figures 3 to 8 As shown, the nozzle module 2 includes a connector 21 and a nozzle 22. The nozzle 22 has an outlet hole 221. The connector 21 is used to connect the feed pipe 1 and the nozzle 22. A receiving cavity 23 is formed between the connector 21 and the nozzle 22. The movable part 3 is disposed in the receiving cavity 23.

[0043] During printing, the filament enters the connector 21 from the feed tube 1, then enters the nozzle 22 from the connector 21, and finally flows out from the outlet hole 221 of the nozzle 22. The connector 21 and the nozzle 22 are set separately before assembly. When assembling the nozzle module 2, the movable part 3 is first placed between the connector 21 and the nozzle 22, and then the connector 21 and the nozzle 22 are assembled and connected, thus setting the movable part 3 in the receiving cavity 23 between the connector 21 and the nozzle 22.

[0044] In this embodiment, the connector 21 is connected to the feed tube 1 and the nozzle 22 respectively to fix the position of the feed tube 1 and the nozzle 22, so as to prevent the feed tube 1 from moving during the printing process and affecting the normal extrusion of the consumables.

[0045] In actual implementation, the connector 21 has multiple through channels, with each feed pipe 1 correspondingly connected to one channel. A heating element is provided on the outside of the connector 21 to heat the consumable material fed through the feed pipe 1, causing the consumable material to melt from a solid state to a liquid state. The liquid consumable material can bypass the moving parts 3 in the receiving cavity 23 and enter the nozzle 22, and finally flow out through the outlet hole 221 of the nozzle 22. The connector 21 and the nozzle 22 are made of high thermal conductivity materials, such as brass or stainless steel, to improve the heating efficiency of the consumable material.

[0046] Optionally, the connector 21 and the nozzle 22 are interference fit, or the connector 21 and the nozzle 22 are connected by screws, or the connector 21 and the nozzle 22 are welded, or the connector 21 and the nozzle 22 are riveted, or the connector 21 and the nozzle 22 are threaded.

[0047] Specifically, the connector 21 has a groove with an inner diameter that matches the outer diameter of the nozzle 22, and at least part of the nozzle 22 is confined within the groove. The nozzle 22 can be confined by an interference fit with the groove wall, by a screw or rivet connection, by welding the outer peripheral wall of the nozzle 22 to the periphery of the groove, or by having threads on the outer peripheral wall of the nozzle 22 and threads on the groove wall, with the nozzle 22 being screwed into the groove.

[0048] Understandably, the connector 21 and the nozzle 22 can be detachably connected to facilitate the replacement of the nozzle 22 and the moving part 3. At the same time, when it is necessary to clean the receiving cavity 23, the nozzle 22 can be directly removed to improve cleaning efficiency.

[0049] In one embodiment of the present invention, such as Figures 3 to 8 As shown, the connector 21 includes a first part 211 and a second part 212 that are connected. The first part 211 is fixedly connected to the feed pipe 1. The first part 211 is provided with a plurality of limiting channels 2111. One feed pipe 1 is connected to one limiting channel 2111. The second part 212 is fixedly connected to the nozzle 22 and is connected to the outlet hole 221 of the nozzle 22.

[0050] Specifically, the feed tube 1 and the limiting channel 2111 are configured in a one-to-one correspondence. Each feed tube 1 is inserted into a limiting channel 2111 of the first part 211 to fix the feed tube 1. Optionally, the outer diameter of the feed tube 1 matches the inner diameter of the limiting channel 2111, and the feed tube 1 and the connector 21 are connected by an interference fit.

[0051] In this embodiment, the second part 212 is used to connect with the nozzle 22. All the limiting channels 2111 of the first part 211 are connected to the second part 212 and are connected to the outlet hole 221 of the nozzle 22 through the second part 212.

[0052] Optionally, the second part 212 and the nozzle 22 are interference fit, or the second part 212 and the nozzle 22 are connected by screws, or the second part 212 and the nozzle 22 are welded, or the second part 212 and the nozzle 22 are riveted, or the second part 212 and the nozzle 22 are threaded.

[0053] In actual implementation, the second part 212 is provided with a groove for limiting the nozzle 22. The groove is connected to the limiting channel 2111 of the first part 211. The nozzle 22 is limited in the groove so as to realize the connection between the nozzle 22 and the limiting channel 2111.

[0054] In one embodiment of the present invention, such as Figure 3 As shown, the feed tube 1 includes a first section 11 and a second section 12 connected together. The outer diameter of the first section 11 is larger than that of the second section 12. The first section 11 is exposed outside the connector 21, and the second section 12 extends into the limiting channel 2111 and is fixedly connected to the first section 211.

[0055] In this embodiment, the outer diameter of the first segment 11 is larger than that of the second segment 12. The outer diameter of the second segment 12 matches the inner diameter of the limiting channel 2111. This facilitates the positioning and installation of the feed pipe 1. During the insertion of the second segment 12 into the limiting channel 2111, when the edges of the first segment 11 and the limiting channel 2111 mutually limit each other and the second segment 12 cannot be further inserted into the limiting channel 2111, the feed pipe 1 and the connector 21 are assembled in place.

[0056] Understandably, the limiting channel 2111 is set through the connector 21, one end of the limiting channel 2111 forms an insertion port for the feed tube 1 to be inserted, and the other end of the limiting channel 2111 forms a communication port that communicates with the nozzle 22.

[0057] In actual implementation, the first segment 11 and the second segment 12 form a first limiting step on the outer peripheral surface of the connection. The first limiting step is used to abut against the outer peripheral edge of the insertion port of the limiting channel 2111 for limiting. The inner diameter of the first segment 11 and the inner diameter of the second segment 12 are the same to ensure that the consumables move smoothly in the feed tube 1.

[0058] Optionally, the limiting channel 2111 includes a first channel segment and a second channel segment that are connected. The inner diameter of the first channel segment is larger than that of the second channel segment. The inner diameter of the first channel segment matches the outer diameter of the second section 12 of the feed pipe 1, and the inner diameter of the second channel segment matches the inner diameter of the feed pipe 1. A second limiting step is formed at the connection between the first and second channel segments. When the second section 12 is inserted into the limiting channel 2111, the end of the second section 12 facing away from the inlet hole 111 abuts against the second limiting step for limitation. During printing, the consumable material sequentially passes through the first section 11, the second section 12 of the feed pipe 1, and the second channel segment of the connector 21 into the receiving cavity 23, then enters the nozzle 22 from the receiving cavity 23, and finally flows out from the outlet hole 221 of the nozzle 22. The setting of the second channel segment allows the connector 21 to directly transfer the heat of the external heating element to the consumable material, ensuring that the solid consumable material is fully heated and melted into a liquid state.

[0059] In one embodiment of the present invention, such as Figures 3 to 4 As shown, the second part 212 is provided with multiple receiving areas 231, which together form a receiving cavity 23. One receiving area 231 is connected to a limiting channel 2111. The radial dimension of the receiving area 231 is larger than the inner diameter of the limiting channel 2111. The movable part 3 is movably disposed within the receiving area 231.

[0060] In this embodiment, the receiving area 231 and the limiting channel 2111 are arranged in a one-to-one correspondence. Each receiving area 231 is connected to a limiting channel 2111. The multiple receiving areas 231 are not directly connected to each other, so as to avoid the liquid consumables flowing into the receiving area 231 from the limiting channel 2111 flowing directly into other receiving areas 231 at the position of the receiving cavity 23, which would affect the anti-backflow effect of the moving part 3.

[0061] Understandably, multiple receiving areas 231 are connected by nozzles 22. During printing, the filament being fed into the corresponding receiving area 231 flows into the nozzle 22 from that receiving area 231. At this time, the liquid filament flows out from the outlet hole 221 of the nozzle 22 and also flows back from the nozzle 22 to other receiving areas 231, applying pressure to the moving parts 3 in the other receiving areas 231. Since the nozzle 22 is located on the side of the second part 212 away from the first part 211, the pressure direction applied to the moving parts 3 by the liquid filament flowing back from the nozzle 22 to other receiving areas 231 can be more closely aligned with the direction of the limiting channel 2111 relative to the moving parts 3. The moving parts 3 can move more accurately towards the limiting channel 2111 to block the feed tube 1.

[0062] In this embodiment, the radial dimension of the receiving area 231 is larger than the inner diameter of the limiting channel 2111, so that the movable part 3 can move smoothly in the receiving area 231 and can block the limiting channel 2111, indirectly blocking the feed pipe 1. It can be understood that the movable part 3 can directly block the feed pipe 1, or it can indirectly block the feed pipe 1 by blocking the limiting channel 2111, disconnecting the connection between the feed pipe 1 and the nozzle 22, thereby achieving the backflow prevention effect of the feed pipe 1.

[0063] In one embodiment of the present invention, such as Figures 3 to 4 As shown, the receiving area 231 and the limiting channel 2111 are connected by a tapered surface 2121.

[0064] In this embodiment, the conical surface 2121 is configured such that the cross-sectional dimension at the connection between the receiving area 231 and the limiting channel 2111 gradually decreases from the side away from the limiting channel 2111 to the side closer to the limiting channel 2111. When the movable part 3 is subjected to the pressure of the liquid consumable and moves towards the feed pipe 1, the movable part 3 will abut against the conical surface 2121 and move along the conical surface 2121. The conical surface 2121 guides the movable part 3, so that the movable part 3 moves accurately towards the limiting channel 2111 and blocks the feed pipe 1.

[0065] Optionally, the conical surface 2121 can be a conical surface or a pyramidal surface, etc. When the conical surface 2121 is a conical surface, it can effectively reduce the moving resistance of the moving part 3 and improve the reliability of the moving part 3 in preventing backflow.

[0066] In one embodiment of the present invention, such as Figures 2 to 4 As shown, the movable component 3 includes multiple movable parts 31, with each movable part 31 correspondingly disposed within a receiving area 231. The movable part 31 can selectively move towards or away from the limiting channel 2111 within the receiving area 231. When the movable part 31 moves towards the side closer to the limiting channel 2111, the movable part 31 can block the limiting channel 2111 to prevent liquid consumables from flowing back from the nozzle 22 to the limiting channel 2111.

[0067] In this embodiment, the movable component 31 is configured in a one-to-one correspondence with the receiving area 231, and each feed pipe 1 is independently protected against backflow by a movable component 31. The movable component 31 indirectly blocks the feed pipe 1 corresponding to the limiting channel 2111 by blocking the limiting channel 2111, thereby achieving the backflow prevention effect.

[0068] Specifically, during the printing process, the consumable material in the feed tube 1 enters the limiting channel 2111 and then flows from the limiting channel 2111 into the receiving area 231. During this process, the consumable material exerts a force on the movable part 31 within the receiving area 231, moving it away from the limiting channel 2111, to prevent the movable part 31 from obstructing the flow of the consumable material from the limiting channel 2111 into the receiving area 231. Finally, the consumable material flows from the receiving area 231 into the nozzle 22. The consumable material flowing into the nozzle 22 exits from the outlet hole 221 of the nozzle 22. The consumable material flowing out will also flow back from the nozzle 22 to other receiving areas 231. At this time, the consumable material entering other receiving areas 231 exerts a force on the moving part 31 away from the nozzle 22, that is, exerts a force towards the limiting channel 2111, causing the moving part 31 in other receiving areas 231 to move towards the side closer to the limiting channel 2111 and block the limiting channel 2111, so as to prevent the consumable material flowing back into the receiving area 231 from further flowing back into the limiting channel 2111, thus achieving the effect of preventing backflow.

[0069] In one embodiment of the present invention, such as Figure 3 , Figures 5 to 8 As shown, the nozzle 22 is provided with multiple storage areas 222 and multiple discharge ports 223. One storage area 222 is connected to one discharge port 223. Multiple discharge ports 223 are all connected to the outlet hole 221. The storage area 222 is connected to the receiving cavity 23. The movable part 3 can selectively move toward the side of the storage area 222 that is close to or away from the nozzle 22.

[0070] Understandably, the storage area 222 is configured one-to-one with the feed pipe 1, and the discharge port 223 is connected to the storage area 222 one-to-one. During printing, the consumable entering the receiving cavity 23 through the feed pipe 1 flows into the corresponding storage area 222. Due to the limited flow rate of the liquid consumable, it accumulates in the storage area 222 and then flows from the discharge port 223 corresponding to the storage area 222 to the outlet hole 221, and finally flows out through the outlet hole 221. The configuration of the storage area 222 allows the consumable to flow continuously and stably from the outlet hole 221.

[0071] In this embodiment, the multiple storage areas 222 are not directly connected to each other, so as to avoid the liquid consumables flowing into the storage area 222 from the feed pipe 1 flowing directly into other storage areas 222, resulting in insufficient concentration of liquid consumables and affecting the quality of consumables flowing out from the outlet hole 221.

[0072] Specifically, multiple storage zones 222 are connected through outlet holes 221. When liquid consumables flow from storage zones 222 to outlet holes 221, the liquid consumables will flow out from outlet holes 221 and will also flow back to other storage zones 222 from other discharge ports 223 connected to outlet holes 221. This will exert a force on the moving parts 3 in the receiving cavity 23 away from the nozzle 22 and the storage zones 222, causing the moving parts 3 corresponding to these storage zones 222 to move toward the side away from the storage zones 222, thereby blocking other feed pipes 1.

[0073] In one embodiment, the storage area 222 has an opening at the end opposite to the discharge port 223 for consumables to flow in. The movable component 3 located within the receiving cavity 23 neither blocks the opening nor enters the storage area 222 through the opening, thus not affecting the flow of consumables from the discharge port 223. Optionally, the movable component 3 is spherically shaped, and the opening is rectangular, with the diameter of the movable component 3 being larger than one side of the opening and smaller than the other side of the opening.

[0074] Specifically, the shape of the hole in the moving part 3 is different from that in the storage area 222 below, which allows the liquid consumable to flow down along the gap and avoids clogging the outlet 223 below.

[0075] In other embodiments, the movable part 3 is supported by a pin or a pusher pin to prevent it from falling. In summary, the movable part 3 needs to have a predetermined gap with the hole in the storage area 222 so that the liquid consumable can flow smoothly from the storage area 222 through the outlet 223 to the outlet hole 221, and then be extruded from the outlet hole 221 to form a three-dimensional model.

[0076] In one embodiment of the present invention, such as Figure 3 As shown, the inlet hole 111, the receiving cavity 23, and the storage area 222 are connected along a first straight line, and the storage area 222, the discharge port 223, and the outlet hole 221 are connected along a second straight line. The second straight line is inclined relative to the first straight line.

[0077] Understandably, since the feed pipe 1 includes multiple components while the nozzle module 2 only has one, in order to better arrange the feed pipe 1, in this embodiment, the inlet hole 111, the receiving cavity 23, and the storage area 222 are connected along a first straight line. This allows the consumable to enter the storage area 222 along the first straight line, reducing the resistance of the consumable entering the storage area 222 from the inlet hole 111. The consumable entering from the inlet hole 111 can smoothly and easily pass through the receiving cavity 23 into the corresponding storage area 222. At the same time, the storage area 222, the outlet 223, and the outlet hole 221 are connected along a second straight line to guide the consumable in the storage area 222 into the outlet hole 221 from the corresponding outlet 223. This also reduces the resistance of the consumable flowing from the storage area 222 through the outlet 223 to the outlet hole 221, making the consumable extruded more smoothly.

[0078] In actual implementation, the direction of the first straight line is usually set as the axial direction of the feed pipe 1 so that the consumables can flow into the storage area 222 from the feed pipe 1. Since the outlet hole 221 needs to supply the consumables from all the feed pipes 1, the outlet hole 221 is usually set in the center. The consumables entering from different inlet holes 111 need to be guided to the outlet hole 221 of the nozzle 22 so that the consumables can be better extruded from the nozzle 22. Therefore, the direction of the second straight line needs to be set from the storage area 222 toward the outlet hole 221, that is, the direction of the second straight line is relatively inclined to the direction of the first straight line.

[0079] In one embodiment of the present invention, such as Figure 3 , Figures 5 to 8 As shown, the bottom walls 2221 of the multiple storage zones 222 are inclined towards the outlet 223. This guides the liquid consumables in the storage zones 222 to the outlet 223, which facilitates a continuous and stable flow of consumables from the storage zones 222 to the outlet 223, and finally out through the outlet hole 221. This effectively improves the extrusion quality of the consumables and reduces consumable residue in the storage zones 222, preventing the nozzle 22 from becoming clogged.

[0080] In one embodiment of the present invention, the plurality of feed pipes 1 are arranged in a straight line, or the plurality of feed pipes 1 are arranged in a uniform circular pattern around the periphery of the nozzle module 2. In actual implementation, the arrangement of the feed pipes 1 can be set according to the actual installation space of the nozzle assembly 100. Optionally, as Figure 1 As shown, the multiple feed tubes 1 can also be arranged in a rectangular array. Optionally, there are 4 feed tubes 1, and the 4 feed tubes 1 are arranged in a rectangular array of 2 rows and 2 columns.

[0081] Optionally, the number of outlet holes 221 is 1, and the number of feed tubes 1 is 2, 3, 4, 5, 6, or 8. In actual implementation, the number of feed tubes 1 can be set according to usage requirements. Multiple feed tubes 1 share one outlet hole 221 of the same nozzle module 2 to extrude consumables. In this way, after switching to consumables corresponding to different feed tubes 1, there is no need to recalibrate the position of the outlet hole 221, which can improve the smoothness and efficiency of printing.

[0082] The present invention also proposes a 3D printer, which includes an extruder and the aforementioned nozzle assembly 100. The extruder is used to feed solid consumables into the inlet hole 111 of the feed tube 1. Since the nozzle assembly 100 adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0083] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention specification and drawings under the technical concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A nozzle assembly for a 3D printer, characterized in that, The nozzle assembly includes: Multiple feed tubes, each feed tube having an inlet hole for receiving consumables in solid form; A nozzle module having an outlet orifice, wherein the inlet orifice corresponding to each feed tube is connected to the outlet orifice, the outlet orifice being used to extrude consumables in liquid form, wherein the outlet orifice is smaller than the inlet orifice; A movable component, which is selectively movable relative to the nozzle module, is used to prevent liquid consumables from flowing back from the nozzle module to the feed pipe.

2. The nozzle assembly as claimed in claim 1, characterized in that, The movable component has a shape including spherical, elliptical, conical, and cylindrical, and its external dimensions are larger than the inner diameter of the feed pipe; or, the movable component is a one-way valve.

3. The nozzle assembly as described in claim 2, characterized in that, The movable component can selectively move toward the side closer to or away from the feed tube. When the movable component moves toward the side closer to the feed tube, it can block the feed tube to prevent liquid consumables from flowing back from the nozzle module to the feed tube.

4. The nozzle assembly as claimed in claim 1, characterized in that, The nozzle module includes a connector and a nozzle. The nozzle has the outlet hole. The connector is used to connect the feed pipe and the nozzle. A receiving cavity is formed between the connector and the nozzle. The movable part is disposed in the receiving cavity.

5. The nozzle assembly as described in claim 4, characterized in that, The connector and the nozzle are either interference-fitted, connected by screws, welded, riveted, or threaded.

6. The nozzle assembly as claimed in claim 4, characterized in that, The connector includes a first part and a second part that are connected. The first part is fixedly connected to the feed pipe and is provided with multiple limiting channels. One feed pipe is connected to one limiting channel. The second part is fixedly connected to the nozzle and is connected to the outlet hole of the nozzle.

7. The nozzle assembly as claimed in claim 6, characterized in that, The second part and the nozzle are either interference fit, or the second part and the nozzle are connected by screws, or the second part and the nozzle are welded, or the second part and the nozzle are riveted, or the second part and the nozzle are threaded.

8. The nozzle assembly as claimed in claim 6, characterized in that, The feed tube includes a first section and a second section connected together. The outer diameter of the first section is larger than that of the second section. The first section is exposed outside the connector, and the second section extends into the limiting channel and is fixedly connected to the first section.

9. The nozzle assembly as claimed in claim 8, characterized in that, The second part is provided with multiple receiving areas, which together constitute the receiving cavity. Each receiving area is connected to a limiting channel. The radial dimension of the receiving area is larger than the inner diameter of the limiting channel. The movable component is movably disposed within the receiving area.

10. The nozzle assembly as claimed in claim 9, characterized in that, The accommodating area and the limiting channel are connected by a tapered surface.

11. The nozzle assembly as claimed in claim 9, characterized in that, The movable component includes multiple movable parts, one of which is disposed in one of the receiving areas. The movable part can selectively move toward the side closer to or away from the limiting channel within the receiving area. When the movable part moves toward the side closer to the limiting channel, it can block the limiting channel to prevent liquid consumables from flowing back from the nozzle to the limiting channel.

12. The nozzle assembly as claimed in claim 4, characterized in that, The nozzle is provided with multiple storage areas and multiple discharge ports. One storage area is connected to one discharge port, and multiple discharge ports are all connected to the outlet hole. The storage area is connected to the receiving cavity. The movable part can selectively move toward the side of the storage area that is close to or away from the nozzle.

13. The nozzle assembly as claimed in claim 12, characterized in that, The inlet hole, the receiving cavity, and the storage area are connected along a first straight line, and the storage area, the discharge port, and the outlet hole are connected along a second straight line, with the second straight line being inclined relative to the first straight line.

14. The nozzle assembly as claimed in claim 12, characterized in that, The bottom walls of the multiple storage areas are inclined toward the discharge port.

15. The nozzle assembly as claimed in claim 1, characterized in that, The multiple feed tubes are arranged in a straight line, or the multiple feed tubes are arranged in a uniform circular pattern around the periphery of the nozzle module.

16. The nozzle assembly as claimed in claim 15, characterized in that, The number of outlet holes is 1, and the number of feed pipes is 2, 3, 4, 5, 6, or 8.

17. A 3D printer, characterized in that, The 3D printer includes an extruder and a nozzle assembly as described in any one of claims 1-16, the extruder being used to deliver solid-form consumables into the inlet orifice of the feed tube.

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