A jet 3D printing device

Abstract

The application discloses a kind of injection 3D printing devices, including feed pipe, mixing pipe, nozzle and rotary drive mechanism, the inclined gas inlet pipe interface of both sides of feed pipe is used for input compressed air and / or compressed carbon dioxide gas;Mixing pipe one end is connected to feed pipe, mixing pipe outside is equipped with gas storage warehouse, the inner side of gas storage warehouse, the outer wall of mixing pipe is equipped with air inlet, and the outer side of gas storage warehouse is equipped with additive interface, for inputting additive and compressed air;Nozzle is rotatably connected at the end of mixing pipe away from feed pipe, and the end of nozzle away from mixing pipe is provided with detachable spray head;Rotary drive mechanism includes driving motor, first gear and second gear, the output end of driving motor is connected with first gear, second gear is arranged outside nozzle, and first gear is engagedly connected with second gear.The application solves the technical problems that extrusion type discharge 3D printing must have contact surface, and existing injection concrete technology injection is relatively dispersed, and cannot realize long-precision path spraying.

Description

TECHNICAL FIELD

[0001] The present invention belongs to the technical field of 3D printing, and particularly relates to a jetting 3D printing device. BACKGROUND

[0002] In the current field of 3D printing technology, especially for applications in the construction industry, traditional methods mainly rely on extrusion molding technology. This method extrudes materials such as plastics, metals, or concrete from a heated nozzle and accumulates them layer by layer along a predetermined path to form the final product or structure. However, this contact printing method has several limitations, especially when it comes to complex and non-planar structures.

[0003] Firstly, traditional 3D printing systems require the printing head to maintain close contact with the printing interface, which limits its ability to handle hollow structures or print around obstacles such as bundled steel bars. Since the printing head cannot deliver materials at a distance from the printing surface, it cannot meet the construction requirements in some special application scenarios, such as adding new layers directly on existing buildings or repair work. Secondly, traditional printed parts without built-in support structures are prone to structural problems. When there is a lack of reinforcing materials such as steel bars, the printed object may deform or even break due to its own weight or external stress. This is a serious problem for structures that need to withstand large loads or be exposed to external forces for a long time.

[0004] Furthermore, for cases where concrete is used as the printing material, the long setting time is a common challenge. Ordinary concrete usually needs 2-5 hours to preliminarily solidify, which greatly prolongs the construction period of the entire project and is not conducive to quickly responding to temporary construction needs. In addition, during this process, if the concrete does not harden uniformly, it may lead to inconsistent strength, affecting the overall performance of the final structure.

[0005] Although existing jetting concrete technology can overcome some of the above problems to some extent, it also has its own defects. Jetting concrete is a method that uses high-pressure gas generated by a gas pump to spray mixed concrete at high speed. This method can cover large areas and quickly fill irregularly shaped spaces. However, due to the dispersed state of the concrete particles during the spraying process, it is difficult to meet the high-precision path control requirements of 3D printing. Moreover, jetting concrete equipment is more suitable for large-area spraying tasks such as wall painting, rather than precise three-dimensional printing tasks.

[0006] In order to overcome the shortcomings of these existing technologies, it is necessary to develop a new type of jetting printing device. SUMMARY

[0007] The application provides a jet 3D printing device, which solves the technical problems that the extrusion type discharging 3D printing must have a contact surface and the existing jet concrete technology is relatively dispersed and cannot realize the jet spraying along a precise path.

[0008] The application provides a jet 3D printing device, which adopts the following technical scheme:

[0009] The jet 3D printing device comprises a material conveying pipe, inclined gas inlet pipe interfaces arranged on both sides of the material conveying pipe and used for inputting compressed carbon dioxide gas and / or compressed air, a material mixing pipe, a gas storage bin arranged around the outside of the material mixing pipe, gas inlet holes arranged around the inside of the gas storage bin and the outer wall of the material mixing pipe, additive interfaces arranged on both sides of the gas storage bin and used for inputting additives and compressed air, a nozzle rotatably connected to the end of the material mixing pipe far from the material conveying pipe, and a detachable spray head arranged at the end of the nozzle far from the material mixing pipe.

[0010] Preferably, the printing device further comprises a rotary driving mechanism, the rotary driving mechanism comprises a driving motor, a first gear and a second gear, the output end of the driving motor is connected with the first gear, the second gear is arranged outside the nozzle, and the first gear is connected with the second gear in a meshing mode.

[0011] Preferably, the spray head is a square port, a rectangular port or a circular port.

[0012] Preferably, the gas inlet pipe interfaces and the material conveying pipe are arranged at an acute angle with respect to the conveying direction of the concrete in the material conveying pipe, and one side of the material conveying pipe is provided with a mounting flange.

[0013] Preferably, the additives are accelerators.

[0014] Preferably, the printing device further comprises a stirrer and an extrusion pump connected with the stirrer, and the extrusion pump is connected with the material conveying pipe through a first pipeline.

[0015] Preferably, the printing device further comprises an air compressor, the air compressor is connected with a first valve, the first valve is connected with a second pipeline, the second pipeline is connected with two third pipelines through a three-way joint, and the third pipelines are connected with the gas inlet pipe interfaces.

[0016] Preferably, the printing device further comprises an additive tank and a water tank, the additive tank is connected with a second valve, the second valve is connected with a fourth pipeline, the water tank is connected with a third valve, the third valve is connected with a fifth pipeline, the fourth pipeline and the fifth pipeline are connected with a sixth pipeline through a three-way joint, the sixth pipeline is connected with a seventh pipeline through a three-way joint, the seventh pipeline is connected with an eighth pipeline through a three-way joint, and the eighth pipeline is connected with the additive interfaces.

[0017] The second pipe and the seventh pipe are connected through the ninth pipe.

[0018] Preferably, the printing device further includes a metering pump connected to a sixth pipe.

[0019] Preferably, the second pipe is provided with a fourth valve, and the second pipe is connected to a tenth pipe through a tee connector. Carbon dioxide gas is introduced into the end of the tenth pipe and is provided with a fifth valve and a check valve.

[0020] The tenth pipe is connected to another air compressor via a tee fitting.

[0021] The beneficial effects of this invention are:

[0022] (1) Accelerate the setting speed of sprayed concrete during 3D printing:

[0023] This invention introduces a highly efficient accelerator mixing mechanism. Gas is delivered into the mixing pipe to disperse the concrete, and then the gas-laden accelerator is introduced into the position closest to the outlet. This greatly improves the uniform mixing of the accelerator and the material, allowing the concrete to solidify in a short time, reducing waiting time and increasing work efficiency. Moreover, the uniformly distributed accelerator also ensures good adhesion between each layer of printing material, enhancing the safety and durability of the overall structure.

[0024] (2) Introducing carbon dioxide waste gas for carbon solidification to enhance the strength of concrete structures:

[0025] When the printing device of this invention sprays onto a location that does not contact the reinforcing steel, compressed carbon dioxide exhaust gas and compressed air can be supplied to the conveying pipe through the tenth pipe and the second pipe. The carbon dioxide exhaust gas reacts with the concrete to form calcium carbonate, increasing the density and durability of the concrete. This process also consumes the carbon dioxide exhaust gas, achieving both pre-dispersing of the concrete material and strengthening of the concrete, while also realizing energy conservation and emission reduction. When the printing device sprays onto a location that contacts the reinforcing steel, the fifth valve is closed, and only compressed air is supplied to the conveying pipe to pre-disperse the concrete material.

[0026] (3) Solving the problem that 3D printing cannot be done on steel bars:

[0027] This invention can spray-print concrete onto pre-tied steel bars along a defined path, thus solving the problem that extrusion-type 3D printing must rely on a contact surface and cannot complete the spraying on the steel bars. It enables long-distance spray printing, thereby forming an irregular structure with a support frame, which plays an important role in reinforcing the structure after concrete printing.

[0028] (4) Improve the accuracy of jet 3D printing:

[0029] This invention improves the material jetting path and enhances the geometric accuracy of printed parts by improving the nozzle design, particularly by using a square or rectangular nozzle. Simultaneously, the nozzle rotation function ensures a consistent print width even at corners, avoiding the umbrella-shaped diffusion problem caused by traditional circular nozzle jetting. Attached Figure Description

[0030] For ease of explanation, the present invention will be described in detail below with reference to specific embodiments and accompanying drawings.

[0031] Figure 1 This is a perspective view of the device in this embodiment;

[0032] Figure 2 This is a top view of the device in this embodiment;

[0033] Figure 3 for Figure 2 Sectional view at FF;

[0034] Figure 4 This is a flowchart of the overall device in this embodiment.

[0035] In the diagram: 1-Feeding pipe; 101-Air inlet interface; 2-Mixing pipe; 201-Air storage chamber; 202-Air inlet; 203-Admixture interface; 3-Nozzle; 301-Spray head; 4-Drive motor; 5-First gear; 6-Second gear; 7-Mounting flange; 8-First pipe; 9-First valve; 10-Second pipe; 11-Third pipe; 12-Second valve; 13-Fourth pipe; 14-Third valve; 15-Fifth pipe; 16-Sixth pipe; 17-Seventh pipe; 18-Eighth pipe; 19-Ninth pipe; 20-Fourth valve; 21-Tenth pipe; 22-Fifth valve; 23-Check valve.

[0036] exist Figure 4 In the diagram, arrow A indicates the direction of concrete delivery, arrow B indicates the direction of compressed air flow, arrow C indicates the direction of compressed air + accelerator flow, arrow D indicates the direction of compressed air + water flow, and arrow E indicates the direction of carbon dioxide exhaust gas flow. Detailed Implementation

[0037] The following are specific embodiments of the present invention described in conjunction with the accompanying drawings, further illustrating the technical solutions of the present invention. However, the present invention is not limited to these embodiments. Specific details, such as particular configurations and components, are provided in the following description merely to aid in a comprehensive understanding of the embodiments of the present invention. Therefore, those skilled in the art should understand that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present invention. Furthermore, for clarity and brevity, descriptions of known functions and structures have been omitted.

[0038] It should be noted that, unless otherwise specified, the embodiments and features described in this invention can be combined with each other.

[0039] like Figures 1-4 As shown, this embodiment provides a jetting 3D printing device, including a feed pipe, a mixing pipe, and a nozzle. The feed pipe 1 is used to transport concrete, and inclined air inlets 101 are provided on both sides for inputting compressed carbon dioxide exhaust gas and / or compressed air. The inclined air inlets 101 form an acute angle with the concrete conveying direction within the feed pipe 1, ensuring that the gas can effectively disperse the concrete and eject it along the direction of the print head. A mounting flange 7 is provided on the outer side of the feed pipe 1 for fixing the printing device to equipment such as a robotic arm.

[0040] One end of the mixing pipe 2 is connected to the conveying pipe 1, and an air storage chamber 201 is arranged around its outer side. Air inlets 202 are arranged around the inner side of the air storage chamber 201 and the outer wall of the mixing pipe 2. Admixture interfaces 203 are provided on both sides of the air storage chamber 201 for inputting pressurized admixtures and gas, while the air inlets 202 are used to introduce pressurized admixtures and gas into the interior of the mixing pipe 2, so that the admixtures and concrete materials are mixed more evenly. The specific admixture selected is an accelerator.

[0041] Nozzle 3 is rotatably connected to the end of mixing pipe 2 away from material delivery pipe 1. A detachable nozzle 301 is provided at the end of nozzle 3 away from mixing pipe 2. Nozzle 301 can be square, rectangular, or circular, allowing for adjustment according to different printing needs. Using a square or rectangular nozzle ensures accurate 3D printing along the spray path, avoiding the problem of ejected material forming a circular umbrella shape, resulting in a large spray area and significant errors. Since the width of a square or rectangular nozzle varies during rotation in 3D printing, making nozzle 3 rotatable ensures that the square or rectangular nozzle 301 rotates with the nozzle 3 during printing, maintaining a consistent printing width. A circular nozzle is suitable for surface coating. After spraying with a square or rectangular nozzle, it can be switched to a circular nozzle to adjust the material viscosity, using a thinner material for surface spraying to fill gaps between layers and make the building surface appear smoother.

[0042] like Figures 1-3 As shown, this device also includes a drive motor 4, a first gear 5, and a second gear 6; the output end of the drive motor 4 is connected to the first gear 5, and the second gear 6 is disposed outside the nozzle 3, with the first gear 5 and the second gear 6 meshing together. By rotating the drive motor 4, the nozzle 3 and the printhead 301 can be rotated, thereby achieving uniform printing by the printhead 301 and maintaining a certain printing width at all times.

[0043] like Figure 4As shown, the device also includes a mixer and an extrusion pump connected to the mixer. The extrusion pump is connected to the conveying pipe 1 through the first pipe 8 and is used to convey the mixed concrete in the mixer to the conveying pipe 1.

[0044] like Figure 4 As shown, this device also includes an air compressor, an admixture tank, a water tank, and a metering pump. The air compressor is connected to a first valve 9, which is connected to a second pipe 10. The second pipe 10 is connected to two third pipes 11 via a tee connector, and the third pipes 11 are connected to an air inlet port 101. The admixture tank is connected to a second valve 12, which is connected to a fourth pipe 13. The water tank is connected to a third valve 14, which is connected to a fifth pipe 15. The fourth pipe 13 and the fifth pipe 15 are connected to a sixth pipe 16 via a tee connector. The sixth pipe 16 is connected to a seventh pipe 17 via a tee connector, and the seventh pipe 17 is connected to an eighth pipe 18 via a tee connector. The eighth pipe 18 is connected to an admixture port 203. The second pipe 10 and the seventh pipe 17 are connected to a ninth pipe 19. The metering pump is connected to the sixth pipe 154 and is used to control the flow rate of the accelerator and water. The second pipeline is equipped with a fourth valve. The second pipeline is connected to the tenth pipeline via a tee joint. Carbon dioxide gas is introduced into the end of the tenth pipeline, which is equipped with a fifth valve and a check valve. The tenth pipeline is connected to another air compressor via a tee joint.

[0045] Specifically, the air compressor can supply compressed air to the feed pipe 1 and the seventh pipe 17 through the second pipe 10 and the ninth pipe 19, respectively. Carbon dioxide exhaust gas enters the tenth pipe, is pressurized by another air compressor, and then enters the second pipe 10. Thus, compressed carbon dioxide exhaust gas and / or compressed air can be supplied to the air inlet port 101. The admixture tank supplies accelerator to the seventh pipe 17 through the fourth pipe 13, and compressed air is input into the admixture port 203 along with the accelerator. The water tank supplies water to the seventh pipe 17 through the fifth pipe, and the water can be input into the admixture port 203 along with the accelerator and compressed air.

[0046] Working principle:

[0047] (1) Concrete conveying and gas dispersion: After the mixer thoroughly mixes the concrete, it is conveyed to the conveying pipe 1 via a squeeze pump. Simultaneously, compressed carbon dioxide exhaust gas and / or compressed air generated by two air compressors enter the conveying pipe 1 through the second pipe 10, the tenth pipe, and the third pipe 11 to pre-disperse the viscous concrete material. Specifically, when the printing device is spraying a position that does not contact the reinforcing steel, compressed carbon dioxide exhaust gas and compressed air can be conveyed to the conveying pipe 1 through the tenth pipe and the second pipe 10. The carbon dioxide exhaust gas reacts with the concrete to form calcium carbonate, increasing the density and durability of the concrete. It can also consume the carbon dioxide exhaust gas, thus achieving both pre-dispersion of the concrete material and strengthening of the concrete, as well as energy saving and emission reduction. When the printing device is spraying a position that contacts the reinforcing steel, the fifth valve is closed, and only compressed air is conveyed to the conveying pipe 1 to pre-disperse the concrete material.

[0048] (2) Mixing admixtures with concrete materials: Compressed air generated by the air compressor enters the seventh pipe 17 through the ninth pipe 19. The quick-setting agent and water enter the metering pump through the second valve 12, the fourth pipe 13, the fifth pipe 14 and the sixth pipe 16. After the flow rate is controlled by the metering pump, they enter the eighth pipe 18 together with the compressed air through the seventh pipe 17, and then enter the admixture interface 203. Finally, they are evenly sprayed onto the concrete materials inside the mixing pipe 2.

[0049] (3) Injection Printing: The nozzle 301 is fitted with a square or rectangular opening. Pressurized gas and uniformly mixed concrete material enter the nozzle 3 and are ejected through the square or rectangular nozzle 301 for 3D printing. The square or rectangular nozzle 301 can rotate, and the rotation angle always remains consistent with the printing trajectory and printing width. At the same time, it can keep up with the changes of steel bars or preset hollow structures, so as to achieve long-distance injection and eject regular shapes like extrusion printing.

[0050] (4) Surface spraying: After the inkjet printing is completed, when surface spraying is required, the nozzle 301 can be replaced with a circular nozzle, and the viscosity of the concrete material can be adjusted to carry out large-area spraying, filling the gaps between the printed layers and forming a smooth interface.

[0051] In summary, during inkjet printing, the device of this embodiment uses compressed carbon dioxide gas and / or compressed air, which are split into two streams and enter the material delivery pipe 1, to uniformly pre-spread the concrete and other materials. Similarly, the pressurized accelerator is split into two streams and enters the air storage chamber 201 of the material delivery pipe. From the air storage chamber 201, multiple annular air inlets 202 enter the material delivery pipe 1. The concrete material blown out by the compressed carbon dioxide gas and / or compressed air mixes quickly and uniformly with the pressurized accelerator material after the accelerator is sprayed into the material delivery pipe and is delivered to the nozzle 301. The mixture is then uniformly sprayed onto the structure, rapidly forming the structure.

[0052] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0053] In the description of this application, it should be understood that the terms "upper" and "lower" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0054] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

Claims

1. A jetting 3D printing apparatus, characterized in that, include: The conveying pipe (1) is provided with inclined air inlet ports (101) on both sides for inputting compressed carbon dioxide gas and / or compressed air; A mixing pipe (2) is connected to a conveying pipe (1) at one end. An air storage chamber (201) is arranged around the outside of the mixing pipe (2). An air inlet (202) is arranged around the inner side of the air storage chamber (201) and the outer wall of the mixing pipe (2). An additive interface (203) is provided on both sides of the air storage chamber (201) for inputting additives and compressed air. The nozzle (3) is rotatably connected to the end of the mixing pipe away from the conveying pipe, and the end of the nozzle (3) away from the mixing pipe (2) is provided with a detachable nozzle (301). An air compressor is connected to a first valve (9), the first valve (9) is connected to a second pipe (10), the second pipe (10) is connected to two third pipes (11) through a tee connector, and the third pipes (11) are connected to an air inlet port (101). The admixture tank and the water tank are connected to a second valve (12), which is connected to a fourth pipe (13). The water tank is connected to a third valve (14), which is connected to a fifth pipe (15). The fourth pipe (13) and the fifth pipe (15) are connected to a sixth pipe (16) via a tee connector. The sixth pipe (16) is connected to a seventh pipe (17) via a tee connector. The seventh pipe (17) is connected to an eighth pipe (18) via a tee connector. The eighth pipe (18) is connected to an admixture interface (203). The second pipe (10) and the seventh pipe (17) are connected to a ninth pipe (19). The second pipe (10) is provided with a fourth valve, and the second pipe (10) is connected to a tenth pipe through a three-way connector. Carbon dioxide gas is introduced into the end of the tenth pipe and a fifth valve and a one-way valve are provided. The tenth pipe is connected to another air compressor via a tee fitting.

2. The jetting 3D printing apparatus according to claim 1, characterized in that, It also includes a rotary drive mechanism, which includes a drive motor (4), a first gear (5) and a second gear (6). The output end of the drive motor (4) is connected to the first gear (5), and the second gear (6) is disposed outside the nozzle (3). The first gear (5) and the second gear (6) are meshed together.

3. The jetting 3D printing apparatus according to claim 1, characterized in that, The nozzle (301) is a square, rectangular, or circular opening.

4. The jetting 3D printing apparatus according to claim 1, characterized in that, The air inlet (101) forms an acute angle with the concrete conveying direction inside the conveying pipe (1); an installation flange (7) is provided on the outer side of the conveying pipe (1).

5. The jetting 3D printing apparatus according to claim 1, characterized in that, The additive is a quick-setting agent.

6. A jetting 3D printing apparatus according to any one of claims 1-5, characterized in that, It also includes a mixer and an extrusion pump connected to the mixer, the extrusion pump being connected to the feed pipe (1) via a first pipe (8).

7. The jetting 3D printing apparatus according to claim 1, characterized in that, It also includes a metering pump, which is connected to the sixth pipe (16).

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