Switchable continuous fiber reinforced composite 3D printing head mechanism

Abstract

According to the switchable continuous fiber reinforced composite material 3D printing head mechanism, different printing heads are switched through a printing head converter, so that tows of different materials or specifications are printed; each printing head comprises a re-conveying module, a shearing module and a printing module, through switching of the multiple printing heads, mixed printing of different base bodies and reinforcement bodies and switching printing of printing tows of different specifications under the same material are achieved, and the effect that the manufacturing efficiency and the manufacturing precision are both achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of composite material 3D printing and molding, and in particular to a switchable continuous fiber reinforced composite material 3D printing head mechanism. Background Art

[0002] Continuous fiber reinforced resin-based composites are materials with thermoplastic resin or thermosetting resin as the matrix and continuous fibers as the reinforcement. With the development of continuous fiber reinforced composite molding and manufacturing methods, additive manufacturing technology has become an important molding method for continuous fiber reinforced resin-based composites due to its advantages of automation, low cost and high efficiency.

[0003] With the continuous development of continuous fiber reinforced composite materials in aerospace, automobile manufacturing, medical and other fields, the demand for integrated manufacturing of composite material structure and function is in urgent need of breakthrough. On the one hand, the traditional composite material layer manufacturing method needs to be changed urgently, and it is impossible to realize the new hybrid mode design of multiple materials and structures within the layer and between the bundles, and it is difficult to achieve the integrated manufacturing requirements of structural functions such as impact resistance, ablation resistance, and electromagnetic absorption; on the other hand, although the emerging composite material 3D printing technology can realize the manufacturing of complex structures, it is still limited to a single reinforcement structure. For example, the continuous fiber reinforced composite material 3D printing device (publication number CN115958785A, name: a variable volume fraction continuous fiber reinforced composite material 3D printing device and method) can realize the change of fiber fraction printing, but it cannot realize the mixed printing of multiple materials and structures; in addition, the existing composite material 3D printing has a contradiction between manufacturing efficiency and precision. The large-size tow has high printing efficiency but low precision, and the small-size tow has high precision but low efficiency, which makes it difficult to achieve a manufacturing effect with both high efficiency and high precision. Summary of the invention

[0004] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the utility model is to provide a switchable continuous fiber reinforced composite material 3D printing head mechanism, which realizes mixed printing of multiple 3D printing prepreg tows by switching multiple print heads.

[0005] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0006] A switchable continuous fiber reinforced composite material 3D printing head mechanism realizes the printing of tows of different materials or specifications by switching different print heads through a print head converter; each print head includes a re-feeding module, a shearing module and a printing module, thereby realizing the mixed printing of different matrixes and reinforcements and the switching printing of printing tows of different specifications under the same material.

[0007] The print head converter includes a converter rotating plate, which is connected to the converter base through converter screws, and a positioning spring is installed inside the converter base. When the converter rotating plate rotates to a certain position, the convex edge on the positioning spring falls into the positioning groove on the converter rotating plate.

[0008] The re-feeding module includes a re-feeding roller pair, a stepper motor, a re-feeding roller frame and a tension spring. The first re-feeding roller in the re-feeding module is directly connected to the stepper motor shaft to provide re-feeding power; the second re-feeding roller is fixed on the re-feeding roller frame to provide directional support and re-feeding friction; one end of the tension spring is connected to the re-feeding roller frame, and the other end is fixed to the print head frame to tighten the two re-feeding rollers, and the pre-impregnated wire is supported and transported by clamping and rotating the re-feeding roller pair.

[0009] The shearing module comprises a shearing blade, and the shearing of the prepreg is completed by moving the shearing blade connected to a steering gear, a motor or a cylinder in a shearing groove.

[0010] The printing module includes a heating device, a printing nozzle, an internal insulation tube of the printing nozzle and a post-printing cooling device, wherein the heating device is connected to the printing nozzle; the internal insulation tube of the printing nozzle is made of Teflon material or a copper throat containing Teflon coating; the post-printing cooling device includes a compressed gas nozzle and a vortex tube near the printing nozzle, wherein the temperature of the compressed gas is reduced by the vortex tube, and the cooled compressed gas is sprayed onto the prepreg after printing, thereby reducing the viscosity of the resin inside the prepreg.

[0011] The heating power of the heating device is 30-200W, achieving temperature control of 30-300°C, and setting different printing temperatures according to different resins of the prepreg tow.

[0012] Compared with the prior art, the beneficial effects of the utility model are:

[0013] Since the utility model adopts a switchable continuous fiber reinforced composite material 3D printing head mechanism, by switching different printing heads through a print head converter, multiple mixed printing of multiple materials can be achieved, thereby improving the surface quality of the printing;

[0014] Since the utility model uses a steering gear, a motor or a cylinder to drive a blade to shear the prepreg in the shearing groove, the shearing module has a low cost, a stable operation process and a high shearing accuracy;

[0015] Since the utility model uses Teflon insulation tube or copper throat containing Teflon coating to insulate the prepreg wire inside the printing nozzle, the temperature of the prepreg wire inside the printing nozzle is effectively reduced, thereby improving the transportation stability of the prepreg wire inside the printing nozzle. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1It is a structural principle diagram of an embodiment of the utility model.

[0017] FIG. 2( a ) is a front view of an embodiment of the utility model, and FIG. 2( b ) is a side view of an embodiment of the utility model.

[0018] Figure 3 2 is a schematic diagram of the structure of a print head converter according to an embodiment of the present utility model. DETAILED DESCRIPTION

[0019] The present invention is further described in detail below in conjunction with the embodiments and drawings.

[0020] Reference Figure 1 A switchable continuous fiber reinforced composite material 3D printing head mechanism is provided, which switches different printing heads through a print head converter 2 to achieve the printing of tows of different materials or specifications; each print head includes a re-feeding module 3, a shearing module 4 and a printing module, so as to achieve the mixed printing of different matrixes and reinforcements and the switching printing of printing tows of different specifications under the same material.

[0021] 2(a), the re-feeding module 3 includes a re-feeding roller pair, a stepping motor, a re-feeding roller frame 3-3 and a tension spring 3-4. The first re-feeding roller 3-1 in the re-feeding module 3 is directly connected to the stepping motor shaft to provide re-feeding power; the second re-feeding roller 3-2 is fixed on the re-feeding roller frame 3-3 to provide directional support and re-feeding friction; one end of the tension spring 3-4 is connected to the re-feeding roller frame 3-3, and the other end is fixed to the print head frame 7, which can tighten the two re-feeding rollers, and the prepreg filament 1 is supported and transported by clamping and rotating the re-feeding roller pair;

[0022] The material of the re-feed roller is selected according to the requirements of the type of printing tow for re-feed friction, including various combinations of nylon and rubber, rubber and polyurethane, polyurethane and nylon, etc.

[0023] 2(a) and 2(b), the shearing module 4 includes a shearing groove, a shearing blade 4-1, a servo 4-2, a motor or a cylinder, and the shearing of the prepreg 1 is completed by moving the shearing blade connected to the servo, the motor or the cylinder in the shearing groove; different shearing methods are selected according to specific needs and material properties, including chopping, cutting or shearing.

[0024] The printing module includes a heating device 5, a printing nozzle 6, an internal insulation tube of the printing nozzle and a post-printing cooling device to realize the printing of the prepreg 1; the heating device 5 is connected to the printing nozzle 6; the internal insulation tube of the printing nozzle 6 is made of Teflon material, and the temperature inside the printing nozzle 6 can be reduced by the insulation tube to prevent the problem that the resin inside the prepreg 1 is unable to pass through the printing nozzle 6 due to softening when heated; the post-printing cooling device includes a compressed gas nozzle and a vortex tube near the printing nozzle 6, the temperature of the compressed gas is reduced by the vortex tube, and the cooled compressed gas is sprayed onto the prepreg 1 after printing, so as to reduce the viscosity of the resin inside the prepreg 1 and improve the printing shaping ability.

[0025] The heating power of the heating device is 30-200W, achieving temperature control of 30-300°C, and setting different printing temperatures according to different resins of the prepreg tow.

[0026] Reference Figure 3 The print head converter 2 includes a positioning spring 2-1, a converter screw 2-2, a converter rotating plate 2-3, and a converter base 2-4. The converter rotating plate 2-3 is connected to the converter base 2-4 through the converter screw 2-2. The positioning spring 2-1 is installed inside the converter base 2-4. When the converter rotating plate 2-3 rotates to a certain position, the convex edge on the positioning spring 2-1 falls into the positioning groove on the converter rotating plate 2-3, which can ensure the positioning accuracy during switching.

[0027] The prepreg resin matrix for 3D printing includes a thermoplastic resin or a thermosetting resin matrix, wherein the thermoplastic resin matrix includes polylactic acid, polyamide, polyetheretherketone, thermoplastic elastomer, etc., and the thermosetting resin matrix includes epoxy resin, acrylate resin, phenolic resin, bismaleimide resin, etc.

[0028] 3D printed prepreg fiber reinforcements include single or mixed fiber reinforcement forms such as continuous carbon fiber, glass fiber, aramid fiber, and quartz fiber.

[0029] The working principle of the utility model is as follows: Figure 1 As shown, the prepreg 1 enters the re-feeding module 3, and the prepreg 1 is transported by the clamping of the re-feeding roller and the power provided by the stepping motor; the prepreg 1 enters the shearing module 4 after passing through the re-feeding module 3, and is sheared by the steering gear, motor or cylinder; finally, the prepreg 1 is printed through the printing nozzle 6 to form a printed part on the printing base plate; the temperature of the compressed gas is reduced by the vortex tube, and the cooled compressed gas is sprayed on the printed prepreg 1, so as to reduce the viscosity of the resin inside the prepreg 1 and improve the printing shaping ability;

[0030] The surface material, radius and pressure between the re-feeding rollers of the re-feeding module 3 can be determined according to the material of the prepreg and the required accuracy;

[0031] The power source of the shearing module 4 can be selected from a steering gear, a motor or a cylinder as needed, and the size of the shearing groove can be determined according to the material of the prepreg;

[0032] The prepreg resin in the printing nozzle 6 is softened by heating through the heating device 5; there is a Teflon insulation tube inside the printing nozzle 6, and the existence of the insulation tube reduces the temperature of the internal channel of the printing nozzle and improves the stability of the prepreg passing through the printing channel.

[0033] The switchable continuous fiber reinforced composite material 3D printing head mechanism of the utility model can complete the printing of pre-impregnated tows of different continuous fibers and different resins. It has a high degree of integration and can realize the mixed printing of multiple materials to meet the requirements of mixed material and structural design. It can also realize the printing of tows of different specifications of the same material to achieve the effect of both manufacturing efficiency and manufacturing precision.

Claims

1. A switchable continuous fiber reinforced composite material 3D printing head mechanism, characterized in that: By switching different print heads through the print head converter, the printing of tows of different materials or specifications can be realized; each print head includes a re-feeding module, a cutting module and a printing module, so as to realize the mixed printing of different bases and reinforcements and the switching printing of tows of different specifications under the same material; The print head converter includes a converter rotating plate, which is connected to the converter base through converter screws, and a positioning spring is installed inside the converter base. When the converter rotating plate rotates to a certain position, the convex edge on the positioning spring falls into the positioning groove on the converter rotating plate.

2. The 3D printing head mechanism according to claim 1, characterized in that: The re-feeding module includes a re-feeding roller pair, a stepper motor, a re-feeding roller frame and a tension spring. The first re-feeding roller in the re-feeding module is directly connected to the stepper motor shaft to provide re-feeding power; the second re-feeding roller is fixed on the re-feeding roller frame to provide directional support and re-feeding friction; one end of the tension spring is connected to the re-feeding roller frame, and the other end is fixed to the print head frame to tighten the two re-feeding rollers, and the pre-impregnated wire is supported and transported by clamping and rotating the re-feeding roller pair.

3. The 3D printing head mechanism according to claim 1, characterized in that: The shearing module comprises a shearing blade, and the shearing of the prepreg is completed by moving the shearing blade connected to a steering gear, a motor or a cylinder in a shearing groove.

4. The 3D printing head mechanism according to claim 1, characterized in that: The printing module includes a heating device, a printing nozzle, an internal insulation tube of the printing nozzle and a post-printing cooling device, wherein the heating device is connected to the printing nozzle; the internal insulation tube of the printing nozzle is made of Teflon material or a copper throat containing Teflon coating; the post-printing cooling device includes a compressed gas nozzle and a vortex tube near the printing nozzle, wherein the temperature of the compressed gas is reduced by the vortex tube, and the cooled compressed gas is sprayed onto the prepreg after printing, thereby reducing the viscosity of the resin inside the prepreg.

5. The 3D printing head mechanism according to claim 4, characterized in that: The heating power of the heating device is 30-200W, achieving temperature control of 30-300°C, and setting different printing temperatures according to different resins of the prepreg tow.

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