Additive manufacturing system and method capable of continuously supplying multiple materials

Abstract

The invention discloses a multi-material continuous supply additive manufacturing system and method.The multi-material continuous supply additive manufacturing system comprises a material storage unit, a material conveying unit, a color master batch conveying unit, a pressure relief unit, a granule extrusion unit and a bottom plate partition heating unit, and the material storage unit is connected with a multi-inlet one-way valve by being perpendicular to a connecting hose; an outlet in the top of the multi-inlet one-way valve is matched with a venturi vacuum generating device to form a material conveying unit; a color master batch conveying unit is additionally arranged above the material conveying pipeline; a pressure relief unit is arranged at the other end of the material conveying pipeline, the lower end of the pressure relief unit is connected with a granular material extrusion unit, and the material extrusion molding bottom plate is provided with a regional heating unit. The automatic feeding device is suitable for the printing conditions of models of various types and sizes, the function of automatic feeding in the long-time printing process is achieved through the conveying unit, and due to the existence of the color master conveying unit, the printed model is not single in color any more, and the appearance of the printed model is diversified.

Description

Technical Field

[0001] The present invention belongs to the field of 3D printing technology, and in particular to an additive manufacturing system and method with continuous supply of multiple materials. Background Art

[0002] 3D printing is a technology that uses digital model files as the basis and uses bondable materials such as powdered metal or plastic to construct objects by printing layer by layer.

[0003] Multi-material 3D printing is a high-tech method for preparing new and controllable materials. Its principle is to achieve three-dimensional molding through layer-by-layer stacking, so that the gradient of multi-material printing increases and different materials can be combined.

[0004] In the process of additive manufacturing, traditional methods face many challenges when dealing with multi-material forming. Limited by the lack of multi-material feeding and recycling solutions, most additive manufacturing equipment can only process one material at a time, which cannot meet the market demand for multi-material composite structures. Especially in large-format manufacturing, due to the large manufacturing area and large material demand, the single material processing method is not only inefficient, but also cannot meet the needs of complex structures.

[0005] In the additive manufacturing process, due to the large scale of the equipment, the requirements for the continuous supply of multiple materials are more stringent. The continuous and stable supply of multiple materials is the key to ensuring the continuity of the manufacturing process and improving manufacturing efficiency. However, the existing multi-material supply system often has problems such as unstable supply, inflexible material switching, and easy blockage. These problems not only affect the efficiency of manufacturing, but also may cause quality problems. Summary of the invention

[0006] The purpose of the present invention is to solve the problems existing in the prior art, and to propose an additive manufacturing system with continuous supply of multiple materials, aiming to solve the problems of unstable supply of multiple materials, inflexible switching, easy blockage, etc. in the prior art, to achieve continuous and stable supply of multiple materials, and to improve the efficiency and quality of large-format additive manufacturing.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions: An additive manufacturing system with continuous multi-material supply, comprising a multi-material drying storage barrel, a venturi vacuum generator, a multi-inlet one-way valve, a material delivery pipeline, a two-inlet one-way mixing joint, a masterbatch feeding screw, a feeding connection funnel with an air outlet, a heating nozzle, and a grid heating bottom plate with different regions; Several of the multi-material drying storage barrels are connected to the feed port of the multi-inlet one-way valve, and the discharge port of the multi-inlet one-way valve is connected to one end of the feed pipeline through a Venturi vacuum generator, and the Venturi vacuum generator is externally connected to a high-pressure air pump; the multi-material drying storage barrels can be opened selectively, and the negative pressure generated by the high-pressure air pump drives the material to be extracted.

[0008] A small material storage pipe is connected to the upper part of the heating nozzle, and an extrusion motor is provided on the side of the small material storage pipe. The extrusion motor squeezes the material in the small material storage pipe toward the heating nozzle. The discharge port of the feeding connection funnel with an air outlet is connected to the small material storage pipe, and the feed port is connected to the other end of the feeding pipeline. The two-inlet-one-way mixing joint is located on the feeding pipeline and is installed on the feeding pipeline through one of its inlet and outlet. The other inlet is provided with a feeding channel with a built-in masterbatch feeding screw. Above the feeding channel is a feeding funnel. Above the feeding funnel is a masterbatch barrel with a porous structure. The feeding of the masterbatch feeding screw controlled by a right-angle motor is embedded on the side of the feeding funnel. The masterbatch barrel with a porous structure has an automatic valve that can be selectively opened and closed. A zoned grid heated base plate is located below the heating nozzles.

[0009] As a further preferred solution, a scraper plate is provided at the connection between the two-inlet and one-way mixing joint and the feeding channel, and a feeding valve is also provided on the feeding channel. The function of the scraper plate can be interpreted as preventing the masterbatch particles from accumulating and clogging at the lower end of the funnel and thus affecting the conveying efficiency, and the feeding valve can be interpreted as controlling the material conveying and termination.

[0010] As a further preferred solution, a heat dissipation module is provided between the heating nozzle and the small material storage tube for preventing heat from being transferred to the small material storage tube.

[0011] As a further preferred scheme, the feeding connecting funnel with air outlet has a built-in feeding pipe and a buffer space. The lower part of the feeding connecting funnel with air outlet is the discharge port. The feed pipe is located in the feeding connecting funnel with the air outlet. The channel formed between the feed pipe and the inner wall of the feeding connecting funnel with the air outlet is the exhaust channel. There is a buffer space between the discharge port and the feed pipe and the exhaust channel. The feed pipe is connected to the inner wall of the feeding connecting funnel with the air outlet through connecting ribs.

[0012] As a further preferred solution, the regional grid heating base plate is divided into nine regional heating modules, and the area of ​​each region is equal. In addition, the heating of the regional grid heating base plate is controlled by the base plate zone heating control module.

[0013] An additive manufacturing method of an additive manufacturing system with continuous supply of multiple materials, comprising the following steps: Step 1: Use modeling software to build a model and generate a slice file; Step 2: According to the color requirements of the model, adjust the ratio of raw materials and masterbatch through the calculated parameters; Step 3: Prepare printing materials according to material requirements and place the printing materials into the storage device; Step 4: The required raw materials and masterbatch colors are selected from the multifunctional drying storage barrel, and then the printing materials are transported to the heating nozzle through the connecting hose with a venturi vacuum device vertically above it. The heating nozzle heats and melts the printing materials under the control of the integrated circuit and starts printing. Beneficial Effects

[0014] (1) The additive manufacturing system adopts an automatic feeding method equipped with a Venturi vacuum generator, so that the granular material can enter the feeding screw quickly, evenly and stably, and a multi-inlet one-way valve is set up to realize the additive manufacturing process of multiple materials. By mixing different types of materials during the printing process, the printed model obtains better physical properties. In addition, multiple drying storage barrels are set up and connected to the multi-inlet one-way valve to dry the material entering the nozzle part, which fully ensures that the extruded material will not have problems such as bubbles during the printing process, thereby affecting the printing quality.

[0015] (2) On the basis of the above, a masterbatch conveying unit was added. By adding masterbatch during the feeding process, the appearance color of the printed model can be changed, which solves the problem of the monotonous appearance of the traditional printing process and makes the printed product more beautiful.

[0016] (3) By adding a feeding connection funnel with an air outlet, the high-pressure gas in the small storage pipe of the nozzle part will be leaked out. In addition, due to the existence of the two-layer annular wall, some granular materials with inertia will be collected here, thus solving the problem that the material cannot enter the storage pipe due to the excessive feeding air pressure of the Venturi vacuum system.

[0017] (4) By designing a heating module to control the heating of the printing base, heating is performed within the area that needs to be printed, and power is not supplied to the unprinted area. This achieves partial heating and effectively controls the energy consumption of the entire equipment, achieving the goal of energy conservation and emission reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention; Figure 2 It is a schematic diagram of the nozzle part of the present invention; Figure 3 It is a schematic diagram of a feeding connection funnel with an air outlet of the present invention; Figure 4 It is a cross-sectional view of the feeding connection funnel with an air outlet of the present invention; Figure 5It is a cross-sectional view of the feeding connection funnel with an air outlet according to the present invention. DETAILED DESCRIPTION

[0019] 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.

[0020] Since additive manufacturing equipment takes a long time and uses a lot of materials when printing large models, in order to ensure good printing results, the printing equipment needs to be fed with materials in a long and stable manner so that the raw materials for printing can be continuously supplied. And by inputting multiple masterbatches to form a variety of printing models, the multi-material supply system can achieve long-term continuous feeding and diversified model printing.

[0021] like Figure 1-4 As shown, a multi-material additive manufacturing system suitable for large-format model printing of the present invention includes a multi-material drying storage barrel 1, a multi-inlet one-way valve 3, a material delivery pipeline 4, and also includes a two-inlet one-way mixing joint 9, a feeding connection funnel with an air outlet 12, a heating nozzle 16, and a bottom plate partition heating control module 18.

[0022] The multi-material drying storage barrel 1 is connected with a multi-inlet one-way valve 3, and the top of the multi-inlet one-way valve 3 is closely matched with the Venturi vacuum generating device 2.

[0023] The top of the venturi vacuum generating device 2 will be inserted into the end of one side of the concave-shaped material conveying pipeline 4 to form a closed pipe opening.

[0024] The two-inlet and one-way mixing joint 9 is placed in the middle of the feeding pipeline 4, and the left and right side pipe openings of the bottom of the two-inlet and one-way mixing joint 9 are connected to the separated end of the feeding pipeline 4; the top of the two-inlet and one-way mixing joint 9 is provided with a feeding channel with a built-in masterbatch feeding screw 11, and above the feeding channel is a feeding funnel 8, and above the feeding funnel 8 is a masterbatch barrel 7 with a porous structure, and the side of the feeding funnel 8 is embedded with a masterbatch feeding screw 11 controlled by a right-angle motor 5 for feeding; the feeding channel is provided with a scraper plate 10 and a feeding valve 6.

[0025] The top opening of the upper end of the feeding connecting funnel 12 with an air outlet matches with the end of one end of the feeding pipeline 4, and the bottom part of the feeding connecting funnel 12 with an air outlet is connected to the small storage tank 13 so as to realize the transportation of the raw materials to the heating nozzle 16.

[0026] The side of the small material storage tube 13 is connected and matched with the extrusion motor 14, the heat dissipation module 15 and the heating nozzle 16 from top to bottom. In addition, the sub-region grid heating bottom plate 17 will be placed at the bottom of the additive manufacturing equipment.

[0027] The multi-inlet one-way valve 3 is composed of four feed pipe openings and one discharge pipe opening, and a Venturi vacuum generating device 2 is provided on the top of the multi-inlet one-way valve 3 .

[0028] The two-inlet-one-through mixing joint 9 is formed of a closed passage with a through-feed pipe connected to the feeding pipe 4 on both sides and a feeding pipe on the top. This method can conveniently control the type and quantity of the feeding material, and can make the printed model molding effect better.

[0029] The top of the feeding connection funnel 12 with air outlet holes is a porous structure evenly distributed; and the inside of the feeding connection funnel 12 with air outlet holes is set as an inner and outer two-layer annular structure.

[0030] The sub-regional grid heating base plate 17 is divided into nine sub-regional heating modules, and the area of ​​each region is equal. In addition, the sub-regional grid heating floor is controlled by the base plate zone heating control module 18 .

[0031] Since the device adopts a Venturi vacuum system and uses a pneumatic feeding method, when light-weight granular materials are pushed into the funnel by air pressure, the materials cannot smoothly enter the small storage tube 13 due to the existence of air pressure, but will be pushed back into the conveying pipeline 4 by air pressure. Therefore, a feeding connection funnel 12 with a self-decompression function is designed; the feeding connection funnel 12 with an air outlet has a built-in feeding pipeline 121 and a buffer space 123, and the lower part of the feeding connection funnel 12 with an air outlet is a discharge port, and the feeding pipeline 121 is located in the feeding connection funnel 12 with an air outlet, and the channel formed between the feeding connection funnel 12 and the inner wall of the feeding connection funnel 12 with an air outlet is an exhaust channel 122, and the buffer space 123 is between the discharge port and the feeding pipeline 121 and the exhaust channel 122, and the feeding pipeline 121 is connected to the inner wall of the feeding connection funnel 12 with an air outlet through a connecting rib.

[0032] The internal structure of this funnel is as follows Figure 5 As shown, it has a double-wall structure, and the bottom of the funnel is a closed structure except for the part connected to the small storage pipe, which ensures that the air pressure generated by the pneumatic feeding method can be released through the structure of the upper part of the funnel, so that it will not affect the normal supply of granular materials; specifically, high-pressure gas and material rush into the buffer space 123 from the feed pipe 121, the material enters the lower part as the discharge port, and the gas is discharged from the exhaust channel 122.

[0033] The printing raw materials can be ABS, PLA, TPU, chopped carbon fiber, etc. In order to adapt to different processing requirements, the printing raw materials can be adjusted according to different molding requirements. Different materials are stored in the storage barrel 1 according to their own characteristics, and can be continuously supplied by the automatic feeding system during a long printing process.

[0034] The present embodiment provides a multi-material continuous supply system suitable for large-format additive manufacturing equipment, including the above-mentioned printing system that can continuously supply materials for a long time, the supply system includes a multi-material drying storage barrel 1, and the top of the multi-material drying storage barrel 1 is provided with a Venturi vacuum generating device 2, the bottom of the Venturi vacuum generating device 2 is connected to the top of the multi-inlet one-way valve 3, and after being combined with the masterbatch module, the raw material and the masterbatch are delivered to the heating nozzle 16 through the Venturi tube, and are sprayed out from the nozzle on the regional heating floor 17 under the action of the heater.

[0035] This embodiment also provides a printing method for a multi-material continuous supply system suitable for large-format additive manufacturing equipment, comprising the following steps: Step 1. First, use the modeling software to build the required model and generate a slice file: Use the slice software to calculate the size of the model suitable for the system, the height of the first layer and the height of each layer printed, the optimal nozzle temperature and the support setting mode, and analyze the influence of different materials on the printing effect; Step 2: Adjust the ratio of raw materials to masterbatches by using the calculated parameters: Import the optimal parameters obtained in step 1 and the slicing software into the additive manufacturing system of the present invention, and use the raw material selector and the masterbatch selector to control the type, quantity and ratio of the raw materials to the masterbatch, so as to achieve the optimal process requirements; Step 3, prepare printing materials: select ABS, PLA, TPU, chopped carbon fiber and other materials as raw materials according to the model requirements, first inject them into the raw material barrel 1 and use a dryer to heat and dry them, and then select a certain raw material as the printing material; Step 4: The multifunctional drying storage barrel 1 selects the required raw materials and masterbatch colors, and then controls the conveying device to convey the printing material to the nozzle 16 through the connecting hose 4 with a Venturi vacuum device vertically above it. The nozzle heater heats and melts the printing material under the control of the integrated circuit and starts printing.

[0036] 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. An additive manufacturing system with continuous supply of multiple materials, characterized in that: The invention comprises a multi-material drying storage barrel (1), a venturi vacuum generating device (2), a multi-inlet one-way valve (3), a material conveying pipeline (4), a two-inlet one-way mixing joint (9), a masterbatch feeding screw (11), a feeding connecting funnel with an air outlet (12), a heating nozzle (16), and a zoned grid heating bottom plate (17); A plurality of the multi-material drying storage barrels (1) are connected to the feed port of a multi-inlet one-way valve (3); the discharge port of the multi-inlet one-way valve (3) is connected to one end of a material delivery pipeline (4) via a Venturi vacuum generating device (2); and the Venturi vacuum generating device (2) is externally connected to a high-pressure air pump; The heating nozzle (16) is connected to a small material storage pipe (13) at the top, and an extrusion motor (14) is provided on the side of the small material storage pipe (13). The extrusion motor (14) squeezes the material in the small material storage pipe (13) toward the heating nozzle (16). The discharge port of the feeding connection funnel (12) with an air outlet is connected to the small material storage pipe (13), and the feed port is connected to the other end of the material delivery pipeline (4); The two-inlet-one-way mixing joint (9) is located on the feed pipe (4) and is installed on the feed pipe (4) through one inlet and one outlet. A feeding channel with a built-in masterbatch feeding screw (11) is provided at the other inlet. A feeding funnel (8) is located above the feeding channel. A masterbatch barrel (7) with a porous structure is located above the feeding funnel (8). A masterbatch feeding screw (11) is embedded in the side of the feeding funnel (8) and is fed by a right-angle motor (5). The sub-region grid heating base plate (17) is located below the heating nozzle (16).

2. The additive manufacturing system with continuous multi-material supply according to claim 1, characterized in that: A scraper plate (10) is provided at the connection between the two-inlet-one-way mixing joint (9) and the feeding channel, and a feeding valve (6) is also provided on the feeding channel.

3. The additive manufacturing system with continuous multi-material supply according to claim 1, characterized in that: A heat dissipation module (15) is provided between the heating nozzle (16) and the small material storage tube (13) for preventing heat from being transferred to the small material storage tube (13).

4. The additive manufacturing system with continuous multi-material supply according to claim 1, characterized in that: The feeding connection funnel (12) with an air outlet has a feed pipe (121) and a buffer space (123) built therein; the lower part of the feeding connection funnel (12) with an air outlet is a discharge port; the feed pipe (121) is located in the feeding connection funnel (12) with an air outlet; a channel formed between the feed pipe (121) and the inner wall of the feeding connection funnel (12) with an air outlet is an exhaust channel (122); a buffer space (123) is formed between the discharge port and the feed pipe (121) and the exhaust channel (122); and the feed pipe (121) is connected to the inner wall of the feeding connection funnel (12) with an air outlet via a connecting rib.

5. The additive manufacturing system with continuous multi-material supply according to claim 1, characterized in that: The sub-regional grid heating bottom plate (17) is divided into nine sub-regional heating modules, and each region has an equal area. In addition, the heating of the sub-regional grid heating bottom plate (17) is controlled by a bottom plate sub-regional heating control module (18).

6. The additive manufacturing method of the additive manufacturing system with continuous multi-material supply according to any one of claims 1 to 5, characterized in that: The steps include: Step 1: Use modeling software to build a model and generate a slice file; Step 2: According to the color requirements of the model, adjust the ratio of raw materials and masterbatch through the calculated parameters; Step 3: Prepare printing materials according to material requirements and place the printing materials into the storage device; Step 4: The required raw materials and masterbatch colors are selected from the multifunctional drying storage barrel (1), and the printing material is transported to the heating nozzle (16) through the connecting hose (4) with a venturi vacuum device vertically above it. The heating nozzle (16) heats and melts the printing material under the control of the integrated circuit and starts printing.

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