CN-121973442-A - Fiber 3D printing device and method thereof

CN121973442ACN 121973442 ACN121973442 ACN 121973442ACN-121973442-A

Abstract

The invention discloses a fiber 3D printing device and a method thereof, and belongs to the technical field of additive manufacturing equipment. The device comprises a frame, a Z-axis transmission mechanism, an X-Y plane movement system, a feeding system and a control system, wherein the Z-axis transmission mechanism adopts a driving unit to drive a circulating transmission part to move, so that a printing platform arranged on the Z-axis transmission mechanism moves unidirectionally and continuously along the Z-axis direction, infinite stroke printing is theoretically realized, and the control system is configured to control the Z-axis transmission mechanism to execute precise micro reverse adjustment of a local area according to the path planning requirement in the process of executing global unidirectional continuous movement so as to realize retrospective processing of the printed area. The invention breaks through the size limitation of the construction space of the traditional equipment, eliminates the interlaminar pause, remarkably improves the manufacturing efficiency, interlaminar bonding strength and fiber continuity of the large complex curved surface fiber reinforced composite material component, and is particularly suitable for the integrated molding of high-performance components such as conformal structure flexible sensors.

Inventors

HAN BIN
Ye hongxi
LIU CHANG
ZHENG PEIYUAN
ZHANG QI
DAI XINRAN
Qin Wenshuo
LIN QIAOQIAO
ZHOU CHENGRUI

Assignees

西安交通大学

Dates

Publication Date: 20260505
Application Date: 20260327

Claims (10)

1. A fiber 3D printing device, comprising: A frame; the Z-axis transmission mechanism is arranged on the frame and comprises a driving unit and a circulating transmission piece driven by the driving unit, a printing platform (11) is arranged on the circulating transmission piece, and the Z-axis transmission mechanism is configured to drive the printing platform (11) to move unidirectionally and continuously along the Z-axis direction; the X-Y plane movement system is arranged on the frame and is used for driving the printing head (12) to move in a horizontal plane; -a feed system for feeding printing material to the print head (12); and the control system is respectively and electrically connected with the Z-axis transmission mechanism, the X-Y plane motion system and the feeding system and is used for controlling the Z-axis feeding of the printing platform (11) to synchronously act with the plane track of the printing head (12).
2. The fiber 3D printing device according to claim 1, characterized in that the drive unit comprises a Z-axis motor (10), a gearwheel (7) and a pinion (8); the circulating transmission part is a closed-loop belt, and the closed-loop belt is arranged on the large gear (7) and the small gear (8) in a surrounding manner; the printing platform (11) is integrated on the surface of the closed-loop belt; the Z-axis motor (10) is configured to drive the large gear (7) and the small gear (8) to rotate and drive the closed-loop belt to circularly move, so that the printing platform (11) can move along the Z-axis direction in a unidirectional continuous mode.
3. The fiber 3D printing device according to claim 1, wherein the X-Y plane motion system comprises: the Y-axis motion assembly comprises a Y-axis motor (5) and a Y-axis section bar (2), wherein the Y-axis motor (5) is configured to drive a horizontal movement module to move along the Y-axis section bar (2) in the Y-axis direction; The X-axis motion assembly comprises an X-axis motor (4) and a horizontal profile guide rail (14) arranged on the horizontal movement module, a tool head (13) is arranged on the horizontal profile guide rail (14), and the printing head (12) is arranged on the tool head (13); The X-axis motor (4) is configured to drive the tool head (13) to move along the horizontal profile rail (14) in the X-axis direction.
4. A fibre 3D printing device according to claim 3, characterized in that the horizontal profile rail (14) comprises a fixed block (51), a timing belt (52), a pulley (53) and a rail (54); the fixed block (51) is connected to the synchronous belt (52) and is used for fixing the tool head (13); and when the belt wheel (53) rotates, the synchronous belt (52) is driven to operate, so that the fixed block (51) slides in the guide rail (54), and the printing head (12) is driven to move in the X-axis direction.
5. The fiber 3D printing device according to claim 1, wherein the printing head (12) comprises a heat dissipation block (61), a throat (63), a heat conduction aluminum block (64) and a spray head (65) in sequence along the material flow direction; a cooling fan (62) is arranged at the cooling block (61) and used for cooling the entered solid wire; The heat-conducting aluminum block (64) is used for heating and melting wires passing through the throat pipe (63); the nozzle (65) is used for extrusion deposition of molten material onto the printing platform (11).
6. The fibrous 3D printing device according to claim 1, wherein the feeding system comprises a feeding motor (1), the printing material comprising continuous carbon fibers and a thermoplastic matrix material; the thermoplastic matrix material is selected from at least one of TPU, PLA or nylon; The feed motor (1) is configured to simultaneously deliver the continuous carbon fibers and the thermoplastic matrix material to the printhead (12) for melt co-extrusion.
7. The fiber 3D printing device of claim 6, wherein the device is configured to prepare a fiber reinforced composite conformal structure flexible vibration sensor; Wherein the continuous carbon fiber is used as a reinforcing phase, the thermoplastic matrix material is used as a matrix phase, and the continuous structure without interlayer pause is formed by stacking the printing heads (12) layer by layer on the printing platform (11) which performs the unidirectional continuous motion.
8. The fiber 3D printing device of claim 1, wherein the control system is further configured to execute a local monotonicity control strategy: in the process of controlling the printing platform (11) to execute global unidirectional continuous motion, controlling the Z-axis transmission mechanism to execute precise micro reverse adjustment in a specific time period according to a preset path planning instruction; And the precise micro-amplitude reverse adjustment enables the printed specific area on the printing platform (11) to trace back to the working position of the printing head (12) for secondary processing, and the unidirectional continuous motion is immediately recovered after the secondary processing is completed.
9. The fiber 3D printing device according to claim 1, further comprising a thermal bed (6), the thermal bed (6) being arranged inside or below the endless drive member and below the deposition area of the printing platform (11); The hot bed (6) is electrically connected with the control system and is used for heating and preserving heat of the printing material deposited on the printing platform (11).
10. A fiber 3D printing method applied to the fiber 3D printing apparatus according to any one of claims 1 to 9, comprising the steps of: The method comprises the steps of converting the surface of a three-dimensional model into a triangular grid by adopting a discretization method, searching adjacent patches by adopting a binary tree traversal algorithm, and enabling the adjacent patches to be coplanar and aligned along a shared edge by rotation and translation transformation; s2, based on the plane expansion diagram obtained in the step S1, sequentially extracting boundary coordinate points based on Euler paths, and adopting a Hilbert curve as a space filling algorithm to fill the paths in the interior, so as to generate a continuous printing path without idle movement; S3, converting the printing path generated in the step S2 into an executable G code and loading the executable G code into the control system; s4, based on the G code, the control system controls the feeding system to feed the printing head (12), controls the X-Y plane movement system to drive the printing head (12) to move in a horizontal plane, and simultaneously controls the Z-axis transmission mechanism to drive the printing platform (11) to move unidirectionally and continuously along the Z-axis direction; according to the path planning requirement, the printing platform (11) is controlled to carry out precise micro reverse adjustment of the local area in the process of executing the unidirectional continuous motion so as to realize retrospective processing of the printed area; And S5, after the printing task is finished, controlling each moving part to reset.

Description

Fiber 3D printing device and method thereof Technical Field The invention belongs to the technical field of additive manufacturing equipment and precise transmission, and particularly relates to a fiber 3D printing device and a method thereof. Background The fiber reinforced composite material (Fiber Reinforced Composites, FRC) has wide application prospect in the fields of aerospace, automobile manufacturing, biomedical and intelligent structure and the like due to the advantages of high specific strength, high specific modulus, strong designability and the like. Although the traditional composite material manufacturing process (such as autoclave forming, winding forming, laying forming and the like) is mature, the problems of high die cost, long production period, difficult manufacturing of components with complex geometric shapes, serious material waste and the like generally exist. In recent years, continuous fiber 3D printing technology (also called fused deposition composite additive manufacturing) is used as an emerging digital manufacturing means, and can realize controllable regulation and control of fiber orientation and integrated forming of a complex structure, and is widely focused by academia and industry. However, the existing continuous fiber 3D printing technology and equipment still face a plurality of serious technical bottlenecks in practical application, and the following aspects are mainly embodied: 1. the construction space is limited, and the integral molding of the large-size component is difficult to realize The Z-axis motion mechanism of the traditional 3D printing equipment mostly adopts a 'lead screw + guide rail' or a 'gear rack' transmission mode. Such rigid drive structures are limited by the physical length of the mechanical components, resulting in a fixed and limited stroke of the printing platform. When the printing height exceeds the equipment stroke, the model must be divided into a plurality of sections for printing respectively, and then assembled by gluing or mechanical connection. The sectional manufacturing mode not only increases the post-treatment process and the time cost, but also introduces interface defects and stress concentration points at the spliced position, thereby seriously weakening the integral mechanical property and the structural integrity of the large-sized component. For large-size conformal structures such as stringers, wing skins or long-distance flexible sensors common in the aerospace field, the conventional equipment cannot realize real continuous integrated manufacturing of 'infinite length'. 2. Interlayer pauses result in inefficiency and poor interfacial bond quality The prior equipment generally adopts a motion control strategy of 'stacking layer by layer', namely after one layer of printing is finished, the Z axis needs to be lifted by one layer, the printing head often needs to pause motion or idle stroke motion during the period, and the next layer of printing is started after the platform is stable. This intermittent mode of operation has significant drawbacks: first, the dwell time between layers reduces overall manufacturing efficiency, especially when printing large-size components, the non-productive time duty is extremely high; Secondly, the most critical problem is that the temperature of the material layer deposited earlier is greatly reduced due to the Inter-layer pause, and when a new layer of high-temperature melt is covered on the material layer, the temperature difference between the two layers is too large, so that the sufficient diffusion and entanglement of a polymer chain segment are hindered, and the Inter-layer bonding strength (Inter-LAMINAR SHEAR STRENGTH, ILSS) is obviously reduced. Experiments show that the interlayer strength of the traditional layer-by-layer printing is only 40% -60% of the body strength of the matrix material, and the interlayer strength becomes a weak link when the workpiece is stressed, so that layering failure is very easy to occur. 3. Complicated curved surface section path planning is difficult, and fiber continuity is damaged When processing a component with a complex concave-convex curved surface or a non-convex polyhedron, the traditional slicing software generally adopts a horizontal layering approximation method (Stair-STEP EFFECT), which not only can generate obvious step effect on the surface of the curved surface and reduce the dimensional accuracy and the surface quality, but also can cause the continuous fiber to be urgently broken or generate severe directional mutation at the interlayer transition. In addition, conventional fill paths (e.g., zig-zag, concentric offset, etc.) tend to involve a large amount of lost motion movement (EMPTY TRAVEL) and frequent acceleration and deceleration turns. For Continuous Carbon Fiber (CCF), frequent scram and scram are very easy to cause buckling, blockage and even fracture of the fiber in the nozzle, and the fiber reinforced continuity i