A magnetic shearing device for continuous fiber filaments

Abstract

The present invention belongs to the technical field of additive manufacturing of continuous fiber composite materials, and discloses a magnetic wire cutting device for continuous fiber filaments, comprising a wire feeding module, a wire cutting module, and a heating module. In order to solve the problem of wire feeding difficulties in the continuous fiber filaments due to the slow response of the wire cutting device during the cutting process, which leads to reduced printing efficiency and poor wire fracture quality, a miniaturized and compact magnetic wire cutting device is designed. The wire cutting mechanism controls the on and off power of the electromagnet to adsorb and detach the iron sheet and then drive the blade to perform rotary shearing. Compared with the traditional servo wire cutting device, the device has a faster response speed and higher wire cutting efficiency; by calculating the wire diameter of the tension spring and the distance between the iron block and the electromagnet, the problem of large fiber filament fracture deformation during the cutting process is improved. The present invention achieves efficient wire cutting while significantly improving the fiber filament fracture deformation through the coordinated work of the miniaturized electromagnetic wire cutting module with the wire feeding module and the heating module, further promoting the improvement of the continuous fiber printing speed.

Description

Technical Field

[0001] The present invention relates to the field of 3D printing of continuous fiber composite materials, and in particular to a magnetic shearing device for continuous fiber filaments. Background Art

[0002] Continuous fiber composite 3D printing has the advantages of strong designability and no need for mold manufacturing. In recent years, it has been used in medical devices, sporting goods and other fields. Continuous fiber composite 3D technology uses a layer-by-layer stacking method to discretize complex parts into multiple two-dimensional feature planes containing geometric information, and forms printing paths in different planes based on the geometric features in each plane. However, within the same plane, the path often produces breakpoints due to the limitations of the component's geometric features, so the end of continuous fiber printing needs to have a wire cutting module to cut the fiber filament. In addition, excessive deformation of the fiber filament during the cutting process will also cause the fiber filament to be stuck in the conduit, thereby affecting the wire feeding module, so the wire cutting module cannot produce excessive deformation when cutting the fiber filament. Therefore, in order to achieve rapid printing of complex samples of continuous fiber composite materials, it is necessary to develop a continuous fiber filament cutting device that can quickly cut the filament with small fracture deformation.

[0003] To address the need for filament cutting functionality during path switching in continuous fiber composite 3D printing, CN117067582A proposes a print head structure for continuous fiber prepreg filaments that uses an electric hydraulic cylinder to drive a filament cutter to cut the prepreg. While this patent achieves continuous filament cutting, the forward and backward movement of the hydraulic cylinder results in a long reaction time, significantly reducing the speed of 3D printing path switching. To address the need for filament cutting speed and filament fracture deformation during path switching in continuous fiber composite 3D printing, CN109016497A proposes a filament cutting device for a continuous fiber reinforced composite 3D printer that uses a servo motor to drive a four-link linkage, which in turn drives a rotating blade to cut the fiber filament. Compared to hydraulic cylinder-driven filament cutting, this method significantly improves filament cutting speed. Furthermore, during the filament cutting process, the upper and lower clamping mechanisms of this device clamp the fiber filament, minimizing deformation during filament cutting. However, the filament cutting process is relatively complex, and the additional clamping mechanism increases the risk of interference between the print head and the printed part, significantly reducing the flexibility of the printing process. Therefore, it is necessary to comprehensively consider the requirements of the fiber path rapid jump on the wire cutting speed and the wire feeding requirements on the fiber fracture deformation, and develop a continuous fiber magnetic wire cutting device that can quickly cut, has a simple process, and has small fracture deformation, so as to realize the rapid prototyping of complex samples of continuous fiber composite materials. Summary of the Invention

[0004] The present invention designs a wire cutting mechanism that controls the on and off power of an electromagnet to attract and detach an iron sheet, thereby driving a blade to perform rotary shearing. Compared with the traditional motor-driven wire cutting method, this method has a greater torque, improving the situation in which the fiber wire cannot be cut due to insufficient torque in the traditional wire cutting mode. In addition, two capillary tubes are introduced into the wire cutting module. By controlling the distance between the capillary tubes, the magnitude of the reverse restraining force on the wire is adjusted, thereby suppressing the deformation of the wire during the shearing process, reducing the deformation of the wire fracture, and significantly improving the quality of the wire cutting.

[0005] The technical solution of the present invention is as follows: a magnetic shearing device for continuous fiber filaments, comprising a wire feeding module A, a wire cutting module B, and a heating module C; the wire feeding module A mainly realizes the active feeding of the continuous fiber filaments; the wire cutting module B drives the blade to cut the fiber filaments by switching the electromagnet, thereby increasing the wire cutting speed while ensuring that the fracture shape of the fiber filaments is reduced; the heating module C realizes the melting and extrusion of the fiber filaments; the fiber filaments are fed to the heating module C through the wire feeding module A, and the wire cutting module B is located between the wire feeding module A and the heating module C to cut the fiber filaments;

[0006] The wire cutting module B includes a magnet mounting seat B1, a knife seat B2, a flange bearing B3, a blade B4, a third guide tube B5, a limit block B6, an electromagnet B7, an iron block B8, a tension spring B9 and a third pressure block B10; the magnet mounting seat B1 is connected to the base A2 from one side of the base A2; the knife seat B2 is fixed to the base A2 from the other side of the base A2 through the flange bearing B3; the blade B4 is fixed to the knife seat B2 to ensure that it moves synchronously with the knife seat B2; the iron block B8 is connected to the knife seat B2; the electromagnet B7 is fixed on the magnet mounting seat B1; the electromagnet B7 is in relative contact or separation with the iron block B8; the limit block B6 is fixed on the base A2, used to limit the distance that the iron block B8 rotates away from the electromagnet B7; one end of the tension spring B9 is connected to the knife seat B2, and the other end is connected to the lower slide A4; the third guide tube B5 is installed on the base A2 and fixed by the third pressure block B10.

[0007] The wire feeding module A includes a stepping motor A1, a base A2, an upper slideway A3, a lower slideway A4, a side plate A5, a rubber wheel A6, a driven wheel base A7, a driven wheel shaft A8, a metal wheel A9, a retaining spring A10, a thrust shaft A11, a fixing ring A12, a first pressure block A13, a second pressure block A14, a first guide tube A15 and a second guide tube A16; the base A2 is fixed on the stepping motor A1; the rubber wheel A6 is fixed on the output shaft of the stepping motor A1; the upper slideway A3 and the lower slideway A4 are fastened to the base A2, and the two ends of the side plate A5 are respectively connected to the ends of the upper slideway A3 and the lower slideway A4; both sides of the driven wheel base A7 are connected to the upper slideway A3 and the lower slide A4; the metal wheel A9 is installed on the driven wheel base A7 through the driven wheel shaft A8 and is fixed by the retaining spring A10; the thrust shaft A11 passes through the side plate A5 and is connected to the driven wheel base A7 through the fixing ring A12; when the thrust shaft A11 rotates and moves, the fixing ring A12 drives the driven wheel base A7 to move; the first conduit A15 and the second conduit A16 are placed on the base A2, the two are located in the same vertical line, and are fixed with the first pressing block A13 and the second pressing block A14 to prevent the conduit from shaking. The fiber filament passes through the first conduit A15, the gap between the metal wheel and the rubber wheel, and the second conduit A16 from the top in sequence.

[0008] The heating module C includes a fan C1, a fan connecting frame C2, a throat C3, a heating rod C4, a heating block C5, a thermocouple C6, a quick-change joint C7, a radiator C8, a first Teflon tube C9, a second Teflon tube C10, a third Teflon tube C11 and a nozzle C12; the radiator C8 is fixed on the base A2, and the fan C1 is fixed on the radiator C8 through the fan connecting frame C2 to cool the radiator C8; the quick-change joint C7 is connected to the radiator C8. It is connected to one end of the radiator C8; the other end of the radiator C8 is connected to the throat C3, the heating block C5, and the nozzle C12 in sequence; the first Teflon tube C9 is connected to the quick-change connector C7; one end of the second Teflon tube C10 is connected to the first Teflon tube C9, and the other end is connected to the nozzle C12; the third Teflon tube C11 is sleeved on the outside of the first Teflon tube C9 and the second Teflon tube C10; the heating rod C4 and the thermocouple C6 are inserted into the corresponding holes of the heating block C5.

[0009] The distance between the metal wheel A9 and the rubber wheel A6 in the wire feeding module A is adjusted by the thrust shaft A11 to ensure stable wire feeding without damaging the performance of the prepreg wire. The diameter D of the prepreg wire and the distance L1 between the metal wheel and the rubber wheel satisfy 0.7D≤L1≤0.9D.

[0010] The distance between the second conduit A16 in the wire feeding module A and the third conduit B5 in the wire cutting module B needs to ensure that the second conduit A16 and the third conduit B5 support the fiber filaments during the cutting process to avoid shear slippage of the fiber filaments, and the distance L2 between the two and the diameter D of the prepreg filaments satisfies D≤L2≤5D.

[0011] The blade B4 in the wire cutting module B rotates and cuts the fiber wire by adsorbing the iron block B8 through the electromagnet B7, and the adsorption mass of the electromagnet B7 is greater than 35kg; the distance L3 between the surface of the iron block B8 and the surface of the electromagnet B7 satisfies 1mm≤L3≤3mm.

[0012] The tension spring B9 in the wire cutting module B ensures that the electromagnet B7 pulls the iron block B8 away from the surface of the electromagnet B7 when the power is off. At the same time, the force of the tension spring B9 cannot affect the attraction force of the electromagnet B7 on the iron block B8. Therefore, the wire diameter of the tension spring B9 needs to meet 0.4mm≤d≤0.6mm.

[0013] The beneficial effects of the present invention are as follows: the continuous fiber filament magnetic wire cutting device proposed in the present invention improves the problems of low wire cutting efficiency and excessive fracture deformation of continuous fiber prepreg when printing complex samples. Rapid wire cutting is achieved through the coordination of the power on and off of the electromagnet and the tension spring, and the volume of the wire cutting module is greatly reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the overall structure of a continuous fiber wire magnetic shearing device of the present invention, which is suitable for printing and shearing continuous fiber wires;

[0015] Figure 2 This is a schematic diagram of the overall structure of the wire feeding module, which is suitable for feeding continuous fiber wire;

[0016] Figure 3 This is a front view of the wire feeding module structure;

[0017] Figure 4 This is a schematic diagram of a wire cutting module, which is suitable for cutting continuous fiber wires;

[0018] Figure 5 This is a schematic diagram of the wire cutting module from another perspective;

[0019] Figure 6 Schematic diagram of a heating module suitable for melting continuous fiber filaments;

[0020] Figure 7 This is a schematic diagram of the heating module from another perspective.

[0021] In the figure: A-wire feeding module, A1-stepping motor, A2-base, A3-upper slide, A4-lower slide, A5-side plate, A6-rubber wheel, A7-driven wheel base, A8-driven wheel shaft, A9-metal wheel, A10-circlip, A11-thrust shaft, A12-fixing ring, A13-first pressure block, A14-second pressure block, A15-first guide tube, A16-second guide tube, B-wire cutting module, B1-magnet mounting seat, B2-knife seat, B3 -Flange bearing, B4-blade, B5-third guide tube, B6-limit block, B7-electromagnet, B8-iron block, B9-tension spring, B10-third pressure block, C-heating module, C1-fan, C2-fan connecting frame, C3-throat, C4-heating rod, C5-heating block, C6-thermocouple, C7-quick-change connector, C8-radiator, C9-first Teflon tube, C10-second Teflon tube, C11-third Teflon tube, C12-nozzle. DETAILED DESCRIPTION

[0022] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings and technical solutions.

[0023] The present invention provides a continuous fiber wire magnetic shearing device, such as Figure 1 As shown, the continuous fiber filament is actively fed by the wire feeding module and then passes through the wire cutting module, and the wire is cut by the wire cutting module when the path jumps.

[0024] A magnetic shearing device for continuous fiber filaments comprises a wire feeding module, a wire cutting module and a heating module; the wire feeding module mainly realizes the active feeding of the continuous fiber filaments; the wire cutting module drives the blade to cut the fiber filaments by switching the electromagnet, thereby increasing the wire cutting speed while ensuring that the fracture shape of the fiber filaments becomes smaller; and the heating module realizes the melting and extrusion of the fiber filaments.

[0025] The wire feeding module includes a stepper motor A1, a base A2, an upper slideway A3, a lower slideway A4, a side plate A5, a rubber wheel A6, a driven wheel base A7, a driven wheel shaft A8, a metal wheel A9, a retaining spring A10, a thrust shaft A11, a fixing ring A12, a first pressure block A13, a second pressure block A14, a first guide tube A15 and a second guide tube A16; the base A2 is fixed to the stepper motor A1 by screws, the rubber wheel A6 is fixed to the output shaft of the stepper motor A1 by a top screw, and the upper slide is fixed to the output shaft of the stepper motor A1 by a top screw. The upper slideway A3 and the lower slideway A4 are fastened to the base A2 with screws. The side panels A5 are connected to both ends of the upper slideway A3 and the lower slideway A4 with two screws. The driven wheel shaft A8 is connected to the side panels with threads. The driven wheel base A7 is connected to the driven wheel shaft A8, and a fixing ring A12 is fixed to the left side of the driven wheel shaft A8. The first and second conduits A15 and A16 are placed on the base A2 for threading the prepreg and are fixed with the first and second pressing blocks A13 and A14 to prevent the conduits from shaking.

[0026] The wire cutting module includes a magnet mounting seat B1, a knife seat B2, a flange bearing B3, a blade B4, a third guide tube B5, a limit block B6, an electromagnet B7, an iron block B8, a tension spring B9, and a third pressure block B10; the magnet mounting seat B1 is connected to the base A2 by screws, the knife seat B2 is fixed to the base A2 by plug screws and the flange bearing B3, the electromagnet B7 is fixed to the magnet mounting seat B1, the iron block B8 is connected to the knife seat B2 by screws, the limit block B6 is fixed to the base A2 to limit the rotational movement of the iron block B8, and one side of the tension spring B9 is connected to the knife seat B2, and the other side is connected to the lower slide A4;

[0027] The heating module includes a fan C1, a fan connecting frame C2, a throat C3, a heating rod C4, a heating block C5, a thermocouple C6, a quick-change joint C7, a radiator C8, a first Teflon tube C9, a second Teflon tube C10, a third Teflon tube C11 and a nozzle C12; the radiator C8 is fixed to the base A2 by two screws, the fan connecting frame C2 is fixed to the radiator C8, the fan C1 is fixed to the fan connecting frame C2 by screws to cool the radiator C8, and the quick-change joint C7 is connected to the base A2 by threads. Above the radiator C8, the first Teflon tube C9 is connected to the quick-change connector C7. The second Teflon tube C10 is connected to the first Teflon tube C9 on one side and to the nozzle C12 on the other side. The third Teflon tube C11 is wrapped around the outside of the first and second Teflon tubes C9 and C10. The throat C3 is connected to the heating block C5 on one side and to the radiator C8 on the other side and is fixed to the radiator C8 with a jackscrew. The nozzle C12 is screwed onto the heating block C5 via threads. The heating rod C4 and thermocouple C6 are inserted into the corresponding holes in the heating block C5.

[0028] The distance between the metal wheel and the rubber wheel in the wire feeding module is adjustable, and the wire feeding is stable without damaging the performance of the prepreg wire. The diameter D of the prepreg wire and the distance L1 between the metal wheel and the rubber wheel need to satisfy 0.7D≤L1≤0.9D.

[0029] The distance between the second conduit A16 in the wire feeding module and the third conduit B5 in the wire cutting module cannot be too large, so as to ensure that the two conduits can provide good support for the fiber filaments during the cutting process and avoid shear slippage of the fiber filaments. The distance L2 between the two conduits and the diameter D of the prepreg wire need to satisfy D≤L2≤5D.

[0030] The blades in the shearing module rotate and shear the fiber by attracting an iron block with an electromagnet. To ensure that the fibers are cut immediately, the electromagnet's mass must be greater than 35 kg. Furthermore, to ensure rapid attraction and strong shear force, the distance L3 between the iron block and the electromagnet must meet the following requirements: 1 mm ≤ L3 ≤ 3 mm.

[0031] The tension spring in the wire cutting module can ensure that the electromagnet pulls the iron block away from the surface of the electromagnet when the power is off. At the same time, the force of the tension spring cannot be too large to affect the attraction of the electromagnet to the iron block. Therefore, the wire diameter d of the tension spring needs to meet 0.4mm≤d≤0.6mm.

[0032] The continuous fiber filament passes through the first duct A15 and the second duct A16, and the part between the first duct A15 and the second duct A16 is exposed. The thrust shaft A11 is rotated by the Allen wrench to adjust the distance between the metal wheel and the rubber wheel. After the condition of 0.7D≤L1≤0.9D is met, the stepper motor A1 is started, and the prepreg passes through the cutting module B and the heating module C under the friction of the rubber wheel and the metal wheel.

[0033] During the printing process, electromagnet B7 is de-energized, and iron block B8 is not engaged, so no wire cutting occurs. When a path change is required, electromagnet B7 is activated, instantly energizing it and engaging iron block B8. Iron block B8 then rotates blade holder B2 and blade B4 to cut the prepreg. After cutting, electromagnet B7 is de-energized, and iron block B8 is pulled away from electromagnet B7 by the tension spring. Limit block B6 ensures that the distance between iron block B8 and electromagnet B7 is within the range for rapid engagement.

[0034] The entire heating module is fixed to the base A2 by two screws. The continuous fiber prepreg passes through the first Teflon tube C9 and the second Teflon tube C10 and is extruded by the nozzle C12. The print head moves along the path direction.

[0035] The present invention provides a magnetic wire shearing device for continuous fiber filaments, in which the wire shearing module is provided with shearing force by an electromagnet, thereby ultimately achieving fast and high-quality wire shearing of continuous fiber composite materials when printing complex samples, significantly improving the work efficiency when printing complex samples.

Claims

1. A continuous fiber magnetic shearing device, characterized in that: The continuous fiber filament magnetic shearing device comprises a wire feeding module (A), a wire cutting module (B) and a heating module (C); the wire feeding module (A) realizes active feeding of the continuous fiber filament; the wire cutting module (B) drives the blade to cut the fiber filament by switching the electromagnet, thereby increasing the wire cutting speed while ensuring that the fracture shape of the fiber filament becomes smaller; the heating module (C) realizes melting and extrusion of the fiber filament; the fiber filament is fed to the heating module (C) through the wire feeding module (A), and the wire cutting module (B) is located between the wire feeding module (A) and the heating module (C) to cut the fiber filament; The wire cutting module (B) comprises a magnet mounting seat (B1), a knife seat (B2), a flange bearing (B3), a blade (B4), a third guide tube (B5), a limit block (B6), an electromagnet (B7), an iron block (B8), a tension spring (B9) and a third pressure block (B10); the magnet mounting seat (B1) is connected to the base (A2) from one side of the base (A2); the knife seat (B2) is fixed to the base (A2) from the other side of the base (A2) through the flange bearing (B3); the blade (B4) is fixed to the knife seat (B2) to ensure that it is in contact with the base (A2). The knife holder (B2) moves synchronously; the iron block (B8) is connected to the knife holder (B2); the electromagnet (B7) is fixed on the magnet mounting base (B1); the electromagnet (B7) and the iron block (B8) are in relative contact or separation; the limit block (B6) is fixed on the base (A2) and is used to limit the distance that the iron block (B8) rotates away from the electromagnet (B7); one end of the tension spring (B9) is connected to the knife holder (B2), and the other end is connected to the lower slide (A4); the third guide tube (B5) is installed on the base (A2) and fixed by the third pressing block (B10); The wire feeding module (A) includes a stepping motor (A1), a base (A2), an upper slideway (A3), a lower slideway (A4), a side plate (A5), a rubber wheel (A6), a driven wheel base (A7), a driven wheel shaft (A8), a metal wheel (A9), a retaining spring (A10), a thrust shaft (A11), a fixing ring (A12), a first pressure block (A13), a second pressure block (A14), a first guide tube (A15) and a second guide tube (A16); The distance between the second conduit (A16) in the wire feeding module (A) and the third conduit (B5) in the wire cutting module (B) must ensure that the second conduit (A16) and the third conduit (B5) support the fiber filament during the cutting process to avoid shearing slippage of the fiber filament. and the diameter D of the prepreg wire .

2. The continuous fiber filament magnetic shearing device according to claim 1, characterized in that: The base (A2) is fixed on the stepper motor (A1); the rubber wheel (A6) is fixed on the output shaft of the stepper motor (A1); the upper slide (A3) and the lower slide (A4) are fastened to the base (A2), and the two ends of the side plate (A5) are respectively connected to the ends of the upper slide (A3) and the lower slide (A4); the two sides of the driven wheel base (A7) slide in the upper slide (A3) and the lower slide (A4); the metal wheel (A9) is installed on the driven wheel base (A7) through the driven wheel shaft (A8) and is fixed by the retaining spring (A10); the thrust shaft (A11 ) passes through the side plate (A5) and is connected to the driven wheel base (A7) through the fixing ring (A12); when the thrust shaft (A11) rotates and moves, the fixing ring (A12) drives the driven wheel base (A7) to move; the first conduit (A15) and the second conduit (A16) are placed on the base (A2), the two are located in the same vertical line, and are fixed with the first pressing block (A13) and the second pressing block (A14) to prevent the conduits from shaking; the fiber filament passes through the first conduit (A15), the gap between the metal wheel and the rubber wheel, and the second conduit (A16) from the top in sequence.

3. The continuous fiber material magnetic shearing device according to claim 1, characterized in that: The heating module (C) includes a fan (C1), a fan connecting frame (C2), a throat (C3), a heating rod (C4), a heating block (C5), a thermocouple (C6), a quick-change connector (C7), a radiator (C8), a first Teflon tube (C9), a second Teflon tube (C10), a third Teflon tube (C11) and a nozzle (C12); the radiator (C8) is fixed on the base (A2), and the fan (C1) is fixed on the radiator (C8) through the fan connecting frame (C2) to cool the radiator (C8); the quick-change connector ( C7) is connected to one end of the radiator (C8); the other end of the radiator (C8) is connected to the throat (C3), the heating block (C5), and the nozzle (C12) in sequence; the first Teflon tube (C9) is connected to the quick-change connector (C7); one end of the second Teflon tube (C10) is connected to the first Teflon tube (C9), and the other end is connected to the nozzle (C12); the third Teflon tube (C11) is sleeved on the outside of the first Teflon tube (C9) and the second Teflon tube (C10); the heating rod (C4) and the thermocouple (C6) are inserted into the corresponding holes of the heating block (C5).

4. A continuous fiber material magnetic shearing device according to any one of claims 1 to 3, characterized in that: The distance between the metal wheel (A9) and the rubber wheel (A6) in the wire feeding module (A) is adjusted by the thrust shaft (A11), so that the wire feeding is stable without damaging the performance of the prepreg wire. The diameter D of the prepreg wire, the distance between the metal wheel and the rubber wheel are satisfy .

5. A continuous fiber magnetic shearing device according to any one of claims 1 to 3, characterized in that: The blade (B4) in the wire cutting module (B) rotates and cuts the fiber wire by adsorbing the iron block (B8) through the electromagnet (B7), and the adsorption mass of the electromagnet (B7) is greater than 35 kg; the distance between the surface of the iron block (B8) and the surface of the electromagnet (B7) is satisfy .

6. A continuous fiber material magnetic shearing device according to any one of claims 1 to 3, characterized in that: The tension spring (B9) in the wire cutting module (B) ensures that the electromagnet (B7) pulls the iron block (B8) away from the surface of the electromagnet (B7) when the power is off. At the same time, the force of the tension spring (B9) cannot affect the attraction force of the electromagnet (B7) on the iron block (B8). Therefore, the wire diameter of the tension spring (B9) needs to meet the requirement of 0.4mm≤d≤0.6mm.

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