A high-precision FDM 4D printing nozzle for metal-plastic functional graded structures

Abstract

This invention relates to the field of printer nozzle technology, and more particularly to a high-precision FDM 4D printing nozzle for metal-plastic functional graded structures. The nozzle includes a first feeding device, two second feeding devices, a feeding connector, a water cooling device, a melting and stirring device, a feeding conduit shell, and multiple filament guides. This invention solves the problems of poor material mixing uniformity in existing technologies. In the design and fabrication of plastic functional graded structures, the composite precision and segregation of the plastic directly affect the performance and interface quality of the functional graded structure. Current plastic functional graded structure designs mainly focus on different material content ratios, requiring material design to be completed before molding. This results in a small range of material variability and poor flexibility. Furthermore, uneven plastic mixing directly causes inconsistencies between the functional graded structure performance and the design, severely leading to interface cracking and molding failure.

Description

Technical Field

[0001] This invention relates to the field of printer nozzle technology, and more particularly to a high-precision FDM 4D printing nozzle for metal-plastic functional gradient structures. Background Technology

[0002] With the rapid development of the manufacturing industry, the demand for complex functional structural components is becoming increasingly urgent, thus placing higher requirements on forming processes, material selection, and structural design. Common 3D printing consumables include metals and non-metals. Compared with traditional manufacturing, it has many advantages, such as enabling personalized and customized manufacturing, eliminating the need for fixtures and tools, lower costs, shorter cycles, and higher material utilization, which greatly improves material utilization. It has developed rapidly worldwide and is widely used in aerospace, automotive, electronics, biomedicine and other fields.

[0003] 3D printing utilizes fused deposition modeling (FDM) of engineering plastics or specialty engineering plastics. Specialty engineering plastics, in particular, possess excellent properties (high strength) and low density (lightweight), and are gradually becoming alternatives to metals in certain applications. However, the properties of pure materials cannot meet the rapidly evolving demands of industry, hence the concept of composite materials has emerged. Current methods primarily involve preparing composite raw materials, drawing them into filaments, and then performing 3D printing. This approach suffers from uneven filament mixing, long cycle times, inflexible proportioning control, and performance enhancement thresholds limited by the material itself, making it difficult to meet the performance requirements of functionally graded structural parts.

[0004] To address the aforementioned issues, prior art patent application number 202210228261.3 discloses a color FDM 3D printer based on three primary colors, which achieves color and gradient color printing in FDM 3D printers through the three primary colors.

[0005] However, in the above methods, the material mixing uniformity is not good. When designing and preparing plastic functional graded structures, the composite precision and segregation of plastic directly affect the performance of functional graded structures and interface quality. Existing plastic functional graded structure design mainly focuses on the design of different material content ratios. Material design is completed before molding, resulting in a small range of material variability and poor flexibility. At the same time, uneven plastic mixing will directly cause the performance of functional graded structures to be inconsistent with the design, which can seriously lead to interface cracking and molding failure. Summary of the Invention

[0006] The purpose of this invention is to provide a high-precision FDM 4D printing nozzle for metal-plastic functional graded structures (FJTs). This aims to address the shortcomings of existing technologies, such as poor material mixing uniformity, the direct impact of plastic composite precision and segregation on FJT performance and interface quality during FJT design and fabrication, and the fact that current FJT design primarily focuses on different material content ratios, requiring material design to be completed before molding. This results in a limited range of material variability and poor flexibility. Furthermore, uneven plastic mixing directly leads to discrepancies between the FJT performance and the design, severely causing interface cracking and molding failure.

[0007] To achieve the above objectives, the present invention employs a high-precision FDM 4D printing metal-plastic functional gradient structure nozzle, comprising a first feeding device, two second feeding devices, a feeding connector, a water cooling device, a melting and stirring device, a feeding conduit shell, and multiple filament guides. The feeding conduit shell is mounted on the printer frame, and the feeding connector is connected to the feeding conduit shell. The first feeding device and the two second feeding devices are both mounted on the feeding connector. One end of each of the multiple filament guides is connected to the first feeding device and the two second feeding devices, respectively, and the other end of each filament guide is placed inside the feeding conduit shell. The water cooling device is connected to the feeding conduit shell, and the melting and stirring device is fixedly connected to the lower end of the water cooling device.

[0008] The first feeding device includes a first motor, a first friction wheel, a first fixed wheel, a fixed wheel connector A, and a guide connector. The guide connector is connected to the feeding connector and is also connected to the corresponding guide tube. The first fixed wheel is connected to the guide connector through the fixed wheel connector A. The first motor is mounted on the guide connector, and the output end of the first motor is fixedly connected to the first friction wheel.

[0009] The second feeding device includes a second motor, a second friction wheel, a second fixed wheel, and a fixed wheel connector B. The second fixed wheel is mounted on the feeding connector via the fixed wheel connector B. The second motor is mounted on the feeding connector, and the output end of the second motor is fixedly connected to the second friction wheel.

[0010] The water-cooling device includes a water-cooled outer shell, a conduit connector, a water-cooled conduit, and a water cooler. The water-cooled outer shell is connected to the outer shell of the feed conduit. The upper end of the conduit connector is connected to multiple wire conduits. The lower end of the conduit connector is connected to the water-cooled conduit. The water cooler is disposed on the outer wall of the water-cooled conduit. The lower end of the water-cooled conduit is connected to the melting and stirring device.

[0011] The melting and stirring device includes a heating block, a throat, a metal mesh, a stirrer, a heat insulation pad, a stirring motor, and a nozzle. The heating block is connected to the water-cooling conduit. The throat and the metal mesh are both disposed inside the heating block. The stirring motor is disposed on the heating block through the heat insulation pad. The output end of the stirring motor is connected to the stirrer, which is also disposed inside the heating block. The nozzle is fixedly connected to the heating block.

[0012] The nozzle comprises a body, an electric wire, a sealing ring, a metal wire, an outer ceramic insulation sleeve, an iron cylinder, an inner ceramic insulation sleeve, and a magnetic induction coil. The body is connected to the heating block. The body has a first groove and a second groove. The sealing ring is disposed in the second groove. One end of the metal wire enters through the second groove, passes through the sealing ring, and is placed in the first groove. The iron cylinder is connected to the body. The inner ceramic insulation sleeve is connected to the iron cylinder. The magnetic induction coil is disposed on the outer wall of the inner ceramic insulation sleeve. The outer ceramic insulation sleeve is threadedly connected to the inner ceramic insulation sleeve.

[0013] This invention discloses a high-precision FDM 4D printing nozzle for metal-plastic functionally graded structures. In practical use, three materials are fed into multiple filament guides via a first feeding device and two second feeding devices, respectively. After being cooled by a water-cooling device, they are melted in a melting and stirring device. The mixed filaments wrap around metal filaments and are ejected from the nozzle tip. When a single cycle ends, a coil is energized to melt and break the metal filaments, preparing for the next cycle until the 4D printing of the functionally graded structure is achieved. During the printing process, to achieve printing of a specific material, the feeding speed of the first feeding device and the two second feeding devices is kept constant; to achieve a gradual increase in material density, the feeding speed of the first feeding device and the two second feeding devices is kept constant. Variable material printing allows for changes in the feeding speed of one or more of the first feeding device and the two second feeding devices, enabling high-precision printing of functional graded structures (FJTs). This addresses the shortcomings of existing technologies, such as poor material mixing uniformity. In the design and fabrication of plastic FJTs, the composite precision and segregation of the plastic directly affect the performance and interface quality of the FJT. Existing plastic FJT designs mainly focus on different material content ratios, with material design completed before molding. This results in a small range of material variability and poor flexibility. Furthermore, uneven plastic mixing directly leads to discrepancies between the FJT performance and the design, severely causing interface cracking and molding failure. Attached Figure Description

[0014] 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 these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the high-precision FDM 4D printing metal-plastic functional gradient structure nozzle of the present invention assembled on the printer frame.

[0016] Figure 2 This is an exploded view of the high-precision FDM 4D printing nozzle for metal-plastic functional gradient structures according to the present invention.

[0017] Figure 3 This is a schematic diagram of the internal structure of the heating block of the present invention.

[0018] Figure 4 This is a schematic diagram of the intersection of multiple filament guide tubes of the present invention.

[0019] Figure 5 This is a cross-sectional view of the water cooling device and melting stirring device of the present invention.

[0020] Figure 6 This is a schematic diagram of the internal structure of the nozzle of the present invention.

[0021] 101-Feed connector, 102-Feed guide tube housing, 103-Wire guide tube, 104-First motor, 105-First friction wheel, 106-First fixed wheel, 107-Fixed wheel connector A, 108-Guide connector, 109-Second motor, 110-Second friction wheel, 111-Second fixed wheel, 112-Fixed wheel connector B, 113-Water-cooled housing, 114-Guide tube connector, 115-Water-cooled guide tube, 116-Water Cooler, 117-Heating block, 118-Throat, 119-Metal mesh, 120-Agitator, 121-Insulation pad, 122-Agitator motor, 123-Nozzle, 124-Main body, 125-Wire, 126-Sealing ring, 127-Metal wire, 128-Outer ceramic insulation sleeve, 129-Iron cylinder, 130-Inner ceramic insulation sleeve, 131-Magnetic induction coil, 132-First groove, 133-Second groove, 134-Cooling fan. Detailed Implementation

[0022] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, but should not be construed as limiting the present invention.

[0023] Please see Figures 1-6 This invention provides a high-precision FDM 4D printing nozzle for metal-plastic functionally graded structures, comprising a first feeding device, two second feeding devices, a feeding connector 101, a water cooling device, a melting and stirring device, a feeding conduit housing 102, and multiple filament guides 103. The feeding conduit housing 102 is mounted on the printer frame, and the feeding connector 101 is connected to the feeding conduit housing 102. The first feeding device and the two second feeding devices are both mounted on the feeding connector 101. One end of each of the multiple filament guides 103 is connected to the first feeding device and the two second feeding devices, respectively, and the other end of each filament guide 103 is placed inside the feeding conduit housing 102. The water cooling device is connected to the feeding conduit housing 102, and the melting and stirring device is fixedly connected to the lower end of the water cooling device.

[0024] In this specific embodiment, during actual use, the three materials are fed into multiple filament guides 103 via the first feeding device and two second feeding devices, respectively. After being cooled by the water cooling device, they are melted in the melting and stirring device. The mixed filaments wrap around the metal wire 127 and are ejected from the nozzle tip. When a single program ends, the coil is energized to melt the metal wire 127, preparing for the next forming operation until the 4D printing of the functionally graded structure is achieved. During the printing process, to achieve printing of a specific material, the feeding speed of the first feeding device and the two second feeding devices is kept constant; to achieve printing of gradient materials... The feeding speed of one or more of the first feeding device and the two second feeding devices can be varied to achieve high-precision functional graded structure printing. This method solves the problem of poor material mixing uniformity in the prior art. In the design and preparation of plastic functional graded structures, the composite precision and segregation of plastic directly affect the performance of functional graded structures and interface quality. The existing design of plastic functional graded structures mainly focuses on the design of different material content ratios. The material design is completed before molding, and the material has a small variable range and poor flexibility. At the same time, uneven plastic mixing will directly cause the performance of functional graded structures to be inconsistent with the design, which will seriously lead to interface cracking and molding failure.

[0025] The first feeding device includes a first motor 104, a first friction wheel 105, a first fixed wheel 106, a fixed wheel connector A107, and a guide connector 108. The guide connector 108 is connected to the feeding connector 101 and is also connected to the corresponding guide tube. The first fixed wheel 106 is connected to the guide connector 108 via the fixed wheel connector A107. The first motor 104 is mounted on the guide connector 108, and the output end of the first motor 104 is fixedly connected to the first friction wheel 105.

[0026] In this specific embodiment, during actual use, the filament enters through the small hole above the guide connector 108 and contacts the first friction wheel 105. The surface of the first friction wheel 105 has raised small teeth. When the filament passes through the gap between the first friction wheel 105 and the first fixed wheel 106, under the squeezing action of the first friction wheel 105 and the first fixed wheel 106, the first friction wheel 105 rotates, driving the filament forward to achieve the purpose of feeding. After passing through the gap between the first friction wheel 105 and the first fixed wheel 106, the filament passes through the connection hole between the guide connector 108 and the filament guide tube 103, enters the interior of the filament guide tube 103, and then leads to the water cooling device.

[0027] Secondly, the second feeding device includes a second motor 109, a second friction wheel 110, a second fixed wheel 111, and a fixed wheel connector B112. The second fixed wheel 111 is mounted on the feeding connector 101 via the fixed wheel connector B112. The second motor 109 is mounted on the feeding connector 101, and the output end of the second motor 109 is fixedly connected to the second friction wheel 110.

[0028] In this specific embodiment, during actual use, the two materials enter the two second feeding devices respectively through the small holes on the left and right sides of the feeding connector 101. The surface of the second friction wheel 110 has raised small teeth. When the filament passes through the gap between the second friction wheel 110 and the second fixed wheel 111, under the squeezing action of the second friction wheel 110 and the second fixed wheel 111, the second friction wheel 110 rotates and drives the filament forward, achieving the purpose of feeding. After passing through the gap between the second friction wheel 110 and the second fixed wheel 111, the filament passes through the connection hole between the feeding connector 101 and the filament guide tube 103, enters the interior of the filament guide tube 103, and then leads to the water cooling device.

[0029] Meanwhile, the water cooling device includes a water cooling shell 113, a conduit connector 114, a water cooling conduit 115, and a water cooler 116. The water cooling shell 113 is connected to the feed conduit shell 102. The upper end of the conduit connector 114 is connected to multiple wire conduits 103. The lower end of the conduit connector 114 is connected to the water cooling conduit 115. The water cooler 116 is disposed on the outer wall of the water cooling conduit 115. The lower end of the water cooling conduit 115 is connected to the melting and stirring device.

[0030] In this specific embodiment, the water cooler has an inlet at its upper edge and an outlet at its lower edge. Water flows in from the upper end and out from the lower end, forming a cold flow that convects with the hot flow of the filament, thus achieving cooling. The interior of the water cooler mainly consists of a layered structure composed of several heat dissipation fins with holes on one side. Each pair of adjacent heat dissipation fins is placed mirror-image along the central axis, maximizing the distance between the holes on the two layers to achieve sufficient water cooling. The water cooler has an inlet at the top center, corresponding to the lower end of the conduit connector 114, and an outlet at the bottom center. The water-cooled conduit 115 leads from the inlet to the outlet. After passing through the water-cooled conduit 115 inside the water cooler, the filament enters the heating and melting device.

[0031] In addition, the melting and stirring device includes a heating block 117, a throat 118, a metal mesh 119, a stirrer 120, a heat insulation pad 121, a stirring motor 122, and a nozzle 123. The heating block 117 is connected to the water-cooling conduit 115. The throat 118 and the metal mesh 119 are both disposed inside the heating block 117. The stirring motor 122 is disposed on the heating block 117 through the heat insulation pad 121. The output end of the stirring motor 122 is connected to the stirrer 120. The stirrer 120 is also disposed inside the heating block 117. The nozzle 123 is fixedly connected to the heating block 117.

[0032] The nozzle 123 includes a body 124, an electric wire 125, a sealing ring 126, a metal wire 127, an outer ceramic insulation sleeve 128, an iron cylinder 129, an inner ceramic insulation sleeve 130, and a magnetic induction coil 131. The body 124 is connected to the heating block 117. The body 124 has a first groove 132 and a second groove 133. The sealing ring 126 is disposed in the second groove 133. One end of the metal wire 127 enters through the second groove 133, passes through the sealing ring 126, and is placed in the first groove 132. The iron cylinder 129 is connected to the body 124. The inner ceramic insulation sleeve 130 is connected to the iron cylinder 129. The magnetic induction coil 131 is disposed on the outer wall of the inner ceramic insulation sleeve 130 and the iron cylinder 129. The outer ceramic insulation sleeve 128 is threadedly connected to the inner ceramic insulation sleeve 130.

[0033] In this specific embodiment, after the filament enters the throat 118 and is initially melted, it passes through the gaps in the metal mesh 119 into the inverted conical stirring chamber inside the heating block 117. Once inside the inverted conical stirring chamber, the stirring motor 122 drives the stirrer 120 to thoroughly stir the filament, achieving the effect of first chopping and then stirring. The front end face of the stirring motor 122 is fixedly connected to the right end face of the heating block 117, and the two contact surfaces are separated by the heat insulation gasket 121. The lower end of the heating block 117 is fixedly connected to the nozzle 123. The magnetic induction coil 131 is energized and de-energized via the wire 125 to achieve the heating function. In FDM... When the molten deposition process ends, the magnetic induction coil 131 is energized through the wire 125, generating high temperature to melt the metal wire 127. The metal wire 127 is fed by an external wire feeder and, under the bonding effect of the plastic material inside the nozzle 123, is ejected from the end of the first groove 132. The sealing ring 126 is provided with a small hole for the metal wire 127 to pass through, ensuring that the molten plastic material is ejected from below the nozzle 123. The uniformly mixed molten filament flows from the heating block 117 to the first groove 132 inside the nozzle 123, driving the metal wire 127 to be ejected from the end of the first groove 132, thus achieving printing.

[0034] Furthermore, the high-precision FDM 4D printing metal-plastic functional gradient structure nozzle also includes a cooling fan 134, which is disposed on the water-cooled housing 113.

[0035] In this specific embodiment, by providing the cooling fan 134, the cooling effect on the filament can be improved.

[0036] Using a high-precision FDM 4D printing nozzle for metal-plastic functional graded structures according to this embodiment, in specific use, three materials are fed into multiple filament guides 103 via the first feeding device and two second feeding devices, respectively. After being cooled by the water cooling device, they are melted in the melting and stirring device. The mixed filament wraps around the metal filament 127 and is ejected from the nozzle tip. When a single program ends, the coil is energized to melt the metal filament 127, preparing for the next forming until the 4D printing of the functional graded structure is achieved. During the printing process, if a specific material is to be printed, the feeding speed of the first feeding device and the two second feeding devices is kept constant. To achieve gradient material printing, the feeding speed of one or more of the first feeding device and the two second feeding devices can be changed to achieve high-precision functional graded structure printing. This method solves the problem of poor material mixing uniformity in the existing technology. In the design and preparation of plastic functional graded structures, the composite precision and segregation of plastic directly affect the performance of functional graded structures and interface quality. The existing design of plastic functional graded structures mainly focuses on the design of different material content ratios. The material design is completed before molding, resulting in a small range of material variability and poor flexibility. At the same time, uneven plastic mixing will directly cause the performance of functional graded structures to be inconsistent with the design, seriously leading to interface cracking and molding failure.

[0037] The above description discloses only one preferred embodiment of the present invention, and should not be construed as limiting the scope of the present invention. Those skilled in the art will understand that all or part of the processes of the above embodiments can be implemented, and equivalent changes made in accordance with the claims of the present invention are still within the scope of the invention.

Claims

1. A high-precision FDM 4D printing nozzle for metal-plastic functionally graded structures, characterized in that, The device includes a first feeding device, two second feeding devices, a feeding connector, a water cooling device, a melting and stirring device, a feeding conduit shell, and multiple filament guide tubes. The feeding conduit shell is mounted on the printer frame. The feeding connector is connected to the feeding conduit shell. The first feeding device and the two second feeding devices are both mounted on the feeding connector. One end of each of the multiple filament guide tubes is connected to the first feeding device and the two second feeding devices, respectively. The other end of each of the multiple filament guide tubes is placed inside the feeding conduit shell. The water cooling device is connected to the feeding conduit shell. The melting and stirring device is fixedly connected to the lower end of the water cooling device. The water cooling device includes a water cooling shell, a conduit connector, a water cooling conduit, and a water cooler. The water cooling shell is connected to the feeding conduit shell. The upper end of the conduit connector is connected to the multiple filament guide tubes. The lower end of the conduit connector is connected to the water cooling conduit. The water cooler is mounted on the outer wall of the water cooling conduit. The lower end of the water cooling conduit is connected to the melting and stirring device. The melting and stirring device includes a heating block, a throat, a metal mesh, a stirrer, a heat insulation pad, a stirring motor, and a nozzle. The heating block is connected to the water-cooling conduit. The throat and the metal mesh are both located inside the heating block. The stirring motor is mounted on the heating block via the heat insulation pad. The output end of the stirring motor is connected to the stirrer, which is also located inside the heating block. The nozzle is fixedly connected to the heating block. The nozzle includes a body, an electric wire, a sealing ring, a metal wire, an outer ceramic insulation sleeve, an iron cylinder, an inner ceramic insulation sleeve, and a magnetic induction coil. The body is connected to the heating block and has a first groove and a second groove. The sealing ring is located in the second groove. One end of the metal wire enters through the second groove, passes through the sealing ring, and is placed in the first groove. The iron cylinder is connected to the body, and the inner ceramic insulation sleeve is connected to the iron cylinder. The magnetic induction coil is located on the outer wall of the inner ceramic insulation sleeve, and the outer ceramic insulation sleeve is threadedly connected to the inner ceramic insulation sleeve.

2. The high-precision FDM 4D printing metal-plastic functionally graded structure nozzle as described in claim 1, characterized in that, The first feeding device includes a first motor, a first friction wheel, a first fixed wheel, a fixed wheel connector A, and a guide connector. The guide connector is connected to the feeding connector and is also connected to the corresponding guide tube. The first fixed wheel is connected to the guide connector through the fixed wheel connector A. The first motor is mounted on the guide connector, and the output end of the first motor is fixedly connected to the first friction wheel.

3. The high-precision FDM 4D printing metal-plastic functionally graded structure nozzle as described in claim 2, characterized in that, The second feeding device includes a second motor, a second friction wheel, a second fixed wheel, and a fixed wheel connector B. The second fixed wheel is mounted on the feeding connector via the fixed wheel connector B. The second motor is mounted on the feeding connector, and the output end of the second motor is fixedly connected to the second friction wheel.

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