Fiber orientation regulation and control shearing screw for screw extrusion type 3D printing

Abstract

The invention relates to the technical field of screw extrusion type 3D printing, and discloses a fiber orientation regulation and control shearing screw for screw extrusion type 3D printing, which comprises a stepping motor, a motor base, a coupler, a bearing, a shearing element, a supporting plate, a machine barrel, a feeding device, a conveying pipe, a water cooling device, a heating device, a spray head and a nozzle. The screw extrusion type 3D printing fiber orientation regulation and control system has the beneficial effects that the shearing element comprises the rotating rod, the rod body piece and the conical head, the shearing element is integrated with the stepping motor, the motor base, the coupler, the bearing, the machine barrel and other components, and the complete screw extrusion type 3D printing fiber orientation regulation and control system is formed; wherein the shearing element can intervene in fiber arrangement from an extrusion source, stable conveying and extrusion of a fiber reinforced composite material are realized by combining a material conveying structure of a feeding device and a material conveying pipe, temperature field control of a water cooling device and a heating device and matching with a forming structure of a spray head and a nozzle, and a hardware basis is provided for fiber orientation regulation and control.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of screw extrusion 3D printing, and particularly relates to a fiber orientation control shearing screw for screw extrusion 3D printing. BACKGROUND

[0002] Screw extrusion 3D printing is an additive manufacturing technology based on the principle of fused deposition. It continuously and stably transports and plasticizes high-viscosity paste materials (such as ceramic slurry, composite materials, etc.) through a rotating screw, and precisely accumulates and forms by using an extrusion system. Compared with traditional piston extrusion, it can realize more uniform extrusion pressure and smoother continuous printing, and is particularly suitable for fine manufacturing of high-performance non-Newtonian fluid materials.

[0003] In the processing of FGF fiber-reinforced thermoplastic composites in screw extrusion 3D printing, the prior art has defects: the ordinary screw adopts a traditional structure without special functional elements, and only relies on the axial transportation of the screw groove. When the molten material flows through the nozzle, it is subjected to forced directional shearing by the narrow gap flow field, resulting in unidirectional arrangement of the fibers along the flow direction, and the anisotropy of the printed part is prominent. At the same time, the shearing flow field distribution of the ordinary screw is uneven, which easily damages the fiber integrity, and its pressure building capacity is insufficient, the transportation efficiency of high-viscosity composite materials is low, and problems such as melt stagnation and nozzle blockage are prone to occur, affecting the printing continuity. The traditional fiber orientation control technology only indirectly intervenes through the rear end or external auxiliary means, does not control the fiber arrangement from the extrusion source, and cannot realize overall uniform orientation control, making it difficult to balance the coordinated improvement of fiber integrity, transportation stability and material performance. SUMMARY

[0004] In view of the above problems of the prior art fiber orientation control shearing screw for screw extrusion 3D printing, the present application is proposed.

[0005] Therefore, the purpose of the present application is to provide a fiber orientation control shearing screw for screw extrusion 3D printing.

[0006] To solve the above technical problems, the present application provides the following technical scheme: a step motor, a motor seat, a shaft coupling, a bearing, a shearing element, a support plate, a barrel, a feeding device, a material conveying pipe, a water cooling device, a heating device, a nozzle and a spray head are provided. The step motor is installed on the motor seat, the shearing element includes a rotating rod, a rod body and a conical head, a limiting boss is arranged on the rotating rod, and a main thread is distributed on the outer surface of the rod body. The shaft coupling connects the output end of the step motor and the rotating rod, the bearing is arranged between the rotating rod and the motor seat, the barrel is arranged outside the rod body of the shearing element, and the barrel is supported on the support plate. The feeding device is communicated with the barrel through a feeding pipe, the barrel is sequentially provided with a water cooling device and a heating device outside, the barrel is connected with a nozzle at the end, the nozzle is provided with a nozzle at the end, the conical head extends into the nozzle and is arranged close to the nozzle.

[0007] As a preferred scheme of the fiber orientation control shear screw for screw extrusion 3D printing, the rotating rod, the rod body and the conical head of the shear element are integrally formed.

[0008] As a preferred scheme of the fiber orientation control shear screw for screw extrusion 3D printing, the main body of the rod body is threaded to cover the feeding section, the compression section and the metering section, the shear element and the inner wall of the barrel form an annular gap, and the shear force generated during rotation promotes the fiber orientation.

[0009] As a preferred scheme of the fiber orientation control shear screw for screw extrusion 3D printing, the limiting boss is used to limit the axial displacement of the shear element, and the bearing is rotatably connected with the outer wall of the rotating rod.

[0010] As a preferred scheme of the fiber orientation control shear screw for screw extrusion 3D printing, one end of the feeding pipe is communicated with the discharge port of the feeding device, the other end is communicated with the feeding area of the barrel, and the feeding section of the rod body is arranged.

[0011] As a preferred scheme of the fiber orientation control shear screw for screw extrusion 3D printing, the water cooling device and the heating device are distributed along the axial direction of the barrel, and are arranged corresponding to different functional sections of the rod body.

[0012] As a preferred scheme of the fiber orientation control shear screw for screw extrusion 3D printing, one end of the nozzle is sealingly connected with the end of the barrel, and the other end is detachably connected with the nozzle.

[0013] As a preferred scheme of the fiber orientation control shear screw for screw extrusion 3D printing, the supporting plate is fixedly connected with the outer wall of the barrel, and is used to support the barrel to maintain a predetermined installation posture.

[0014] As a preferred scheme of the fiber orientation control shear screw for screw extrusion 3D printing, the two ends of the shaft coupling are respectively fixedly connected with the output shaft of the stepping motor and the end of the rotating rod, so as to realize power transmission.

[0015] As a preferred solution of the fiber orientation control shearing screw for screw extrusion 3D printing, the conical head of the shearing element is tapered, and the end thereof is close to the discharge port of the nozzle for guiding the material to flow to the nozzle.

[0016] The shearing element includes a rotating rod, a rod body, and a conical head, and is integrated with a stepper motor, a motor base, a shaft coupling, a bearing, a barrel, and other components to form a complete fiber orientation control system for screw extrusion 3D printing, wherein the shearing element can intervene in fiber arrangement from the extrusion source, and in combination with the material conveying structure of the feeding device and the conveying pipe, the temperature field control of the water cooling device and the heating device, and the forming structure of the nozzle and the nozzle, the stable conveying and extrusion of the fiber reinforced composite material are realized, and a hardware foundation for fiber orientation control is provided. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creating labor. Among them: Fig. 1 It is a schematic diagram of the overall structure of the present application.

[0018] Fig. 2 It is a schematic diagram of the cross-sectional structure of the present application.

[0019] Fig. 3 It is a schematic diagram of the rod body structure of the present application.

[0020] In the figure: 1, stepper motor; 2, feeding device; 3, conveying pipe; 4, rod body; 5, water cooling device; 6, heating device; 7, nozzle; 8, nozzle; 9, motor base; 10, shaft coupling; 11, bearing; 12, supporting plate; 13, barrel; 14, main thread; 15, limiting boss; 16, rotating rod; 17, conical head; 18, shearing element. DETAILED DESCRIPTION

[0021] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the drawings.

[0022] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application, but the present application can also be implemented in other ways different from those described herein, and those skilled in the art can make similar generalizations without departing from the connotation of the present application, therefore the present application is not limited to the specific embodiments disclosed below.

[0023] Second, the "one embodiment" or "an embodiment" referred to herein means a specific feature, structure, characteristic, or combination of features and / or characteristics described herein that can be included in at least one implementation of the present application. The various appearances of "in one embodiment" or "an embodiment" in the specification are not necessarily all referring to the same embodiment.

[0024] Third, the present application is described in detail in conjunction with the schematic diagram, and in the detailed description of the embodiments of the present application, the cross-sectional view of the device structure is locally enlarged without the general proportion for the convenience of description, and the schematic diagram is only an example, which should not limit the scope of protection of the present application herein. In addition, the three-dimensional spatial dimensions of length, width and depth should be included in actual manufacture.

[0025] Embodiment 1 Reference Figs. 1-3 For the first embodiment of the present application, a fiber orientation control shearing screw for screw extrusion 3D printing is provided, which comprises a stepper motor 1, a motor base 9, a shaft coupling 10, a bearing 11, a shearing element 18, a supporting plate 12, a barrel 13, a feeding device 2, a material conveying pipe 3, a water cooling device 5, a heating device 6, a spray head 7 and a nozzle 8. The stepper motor 1 is installed on the motor base 9, the shearing element 18 comprises a rotating rod 16, a rod body 4 and a conical head 17, the rotating rod 16 is provided with a limiting boss 15, and the outer surface of the rod body 4 is distributed with a main thread 14. The shaft coupling 10 connects the output end of the stepper motor 1 with the rotating rod 16, the bearing 11 is arranged between the rotating rod 16 and the motor base 9, the barrel 13 is sleeved outside the rod body 4 of the shearing element 18, and the barrel 13 is supported on the supporting plate 12. The feeding device 2 is communicated with the barrel 13 through the material conveying pipe 3, the barrel 13 is sequentially provided with the water cooling device 5 and the heating device 6 outside, the barrel 13 is connected with the spray head 7 at the end, the spray head 7 is provided with the nozzle 8 at the end, and the conical head 17 extends into the spray head 7 and is arranged close to the nozzle 8.

[0026] The shearing element 18 comprises the rotating rod 16, the rod body 4 and the conical head 17, the shearing element 18 is integrated with the stepper motor 1, the motor base 9, the shaft coupling 10, the bearing 11, the barrel 13 and other components to form a complete fiber orientation control system for screw extrusion 3D printing, the shearing element can intervene in the fiber arrangement from the extrusion source, the material conveying structure of the feeding device 2 and the material conveying pipe 3, the temperature field control of the water cooling device 5 and the heating device 6, and the forming structure of the spray head 7 and the nozzle 8 are combined to realize the stable conveying and extrusion of the fiber reinforced composite material, thereby providing a hardware basis for the fiber orientation control.

[0027] Specifically, the rotating rod 16, the rod body 4 and the conical head 17 of the shearing element 18 are integrally formed.

[0028] The rotating rod 16, the rod body 4 and the conical head 17 of the shearing element 18 are integrally formed, which greatly improves the stability and dimensional accuracy of the structure, avoids the risk of material accumulation at the segmented connection, reduces the fiber distribution deviation caused by screw vibration during printing, and ensures the stability of material conveying and fiber orientation control.

[0029] Further, the main thread 14 of the rod body 4 covers the feeding section, the compression section and the metering section, and the shearing element and the inner wall of the barrel 13 form an annular slit, which generates shear force during rotation to promote fiber orientation.

[0030] The main thread 14 of the rod body 4 covers the feeding section, the compression section and the metering section, which ensures continuous axial conveying of the material; and the annular slit formed by the shearing element and the inner wall of the barrel 13 can generate a circumferential shear flow field, breaking the axial shear limitation of ordinary screws only relying on the narrow slit of the nozzle, and actively inducing the transformation of enhanced fibers from unidirectional arrangement to spatial spiral orientation, effectively improving the anisotropy problem of the printed part.

[0031] Preferably, the limiting boss 15 is used to limit the axial displacement of the shearing element 18, and the bearing 11 is in rotating cooperation with the outer wall of the rotating rod 16.

[0032] The limiting boss 15 on the rotating rod 16 can limit the axial displacement of the shearing element 18, avoiding axial displacement of the screw during operation; at the same time, the rotating cooperation of the bearing 11 and the outer wall of the rotating rod 16 reduces the friction resistance of the screw operation, ensures the stable transmission of the shearing element 18, and further improves the stability of material conveying and fiber orientation control.

[0033] Further, one end of the material conveying pipe 3 is connected to the discharge port of the feeding device 2, and the other end is connected to the feeding area of the barrel 13, and is arranged corresponding to the feeding section of the rod body 4.

[0034] The material conveying pipe 3 is arranged corresponding to the feeding section of the rod body 4, which can accurately convey the material of the feeding device 2 to the feeding area of the rod body 4, ensuring that the material can quickly enter the conveying flow channel of the main thread 14, avoiding the material to be stranded in the feeding link, improving the initial conveying efficiency of the material, and laying a foundation for subsequent compression, melting and shearing control.

[0035] In use, the rotating rod 16, the rod body 4 and the conical head 17 of the shearing element 18 are assembled into the barrel 13, the step motor 1 and the rotating rod 16 are connected through the shaft coupling 10, and the bearing 11 is installed between the rotating rod 16 and the motor base 9; the barrel 13 is supported on the supporting plate 12, the connection of the feeding device 2 with the material conveying pipe 3 and the barrel 13, and the assembly of the water cooling device 5, the heating device 6 and the barrel 13 are completed, and finally the nozzle 7 and the nozzle 8 are connected; According to the type of the fiber-reinforced composite material to be printed, the heating temperature of the heating device 6, the cooling parameters of the water cooling device 5, and the initial rotating speed of the stepping motor 1 are set; The fiber-reinforced thermoplastic composite material is added to the feeding device 2, and the material is transported to the feeding area of the barrel 13 through the conveying pipe 3 and enters the flow channel of the main thread 14 of the feeding section of the rod member 4. The stepping motor 1 is started to drive the shearing element 18 to operate, and the material is transported and pre-melted through the main thread 14 of the feeding section and the compression section of the rod member 4; when the material flows through the shearing element, the fibers are induced to form a spatial spiral orientation under the action of the annular shearing flow field of the annular slit. The shearing-regulated molten material is guided through the conical head 17, enters the nozzle 8 through the nozzle 8, and is extruded to complete the printing forming by cooperating with the movement of the 3D printing platform; after the printing is completed, the stepping motor 1 and the temperature field device are turned off, and the nozzle 8 is disassembled for cleaning after the equipment is cooled, and the equipment maintenance is completed.

[0036] In summary, the shearing element 18 includes the rotating rod 16, the rod member 4, and the conical head 17, and the shearing element 18 is integrated with the stepping motor 1, the motor base 9, the shaft coupling 10, the bearing 11, the barrel 13, and other components to form a complete screw extrusion type 3D printing fiber orientation regulation system; wherein the shearing element can intervene the fiber arrangement from the extrusion source, and the material conveying structure of the feeding device 2 and the conveying pipe 3, and the temperature field control of the water cooling device 5 and the heating device 6, cooperate with the forming structure of the nozzle 8 and the nozzle 8 to realize the stable transportation and extrusion of the fiber-reinforced composite material, and provide a hardware foundation for fiber orientation regulation.

[0037] Embodiment 2 Reference Figs. 1-3 For the second embodiment of the present application, which is different from the first embodiment, the water cooling device 5 and the heating device 6 are distributed along the axial direction of the barrel 13 and arranged corresponding to different functional sections of the rod member 4.

[0038] Among them, the water cooling device 5 and the heating device 6 are distributed along the axial direction of the barrel 13 and correspond to different functional sections of the rod member 4, which can provide an adaptive temperature field for the material state of the feeding section, the compression section, and the metering section, realize the gradient heating and cooling of the material, and ensure the state stability of the material in different transportation stages, avoiding the performance degradation of the material caused by local overheating or insufficient cooling.

[0039] Specifically, one end of the nozzle 8 is sealingly connected with the end of the barrel 13, and the other end is detachably connected with the nozzle 8.

[0040] The sealing connection of the nozzle 7 and the machine barrel 13 avoids the risk of leakage of the molten material; and the detachable connection of the nozzle 7 and the nozzle 8 facilitates the replacement of nozzles 8 of different specifications according to the printing requirements, and also facilitates the cleaning and maintenance of the nozzle 8, thereby reducing the influence of nozzle blockage on the printing continuity.

[0041] Further, the support plate 12 is fixedly connected with the outer wall of the machine barrel 13, for supporting the machine barrel 13 to maintain a predetermined installation posture.

[0042] The fixed connection of the support plate 12 and the outer wall of the machine barrel 13 can stably support the machine barrel 13 in a predetermined posture, avoiding the inclination or shaking of the machine barrel 13 during printing, thereby ensuring the stability of the gap between the machine barrel 13 and the shearing element 18, and further ensuring the uniformity of the shearing flow field and the continuity of the material conveying.

[0043] Further, the two ends of the shaft coupling 10 are fixedly connected with the output shaft of the stepping motor 1 and the end of the rotating rod 16 respectively, to realize power transmission.

[0044] The shaft coupling 10 realizes the power transmission between the stepping motor 1 and the rotating rod 16, ensures that the rotating speed of the stepping motor 1 can be accurately transmitted to the shearing element 18, makes the operating speed of the shearing element controllable, provides a reliable power basis for the adjustment of process parameters, and ensures the accuracy of fiber orientation control.

[0045] Further, the conical head 17 of the shearing element 18 is conical, and the distal end thereof is close to the discharge port of the nozzle 8, for guiding the material to flow to the nozzle 8.

[0046] The conical structure of the conical head 17 and the setting close to the discharge port of the nozzle 8 can guide the molten material after shearing control, so that the material can flow more smoothly into the narrow gap flow channel of the nozzle 8, avoid the material to stay in the nozzle 7, and assist in maintaining the stability of the flow direction of the material, thereby ensuring the precision of the extrusion molding.

[0047] It is important to note that the construction and arrangement of the application shown in the various exemplary embodiments is illustrative only. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review the present disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter described herein. For example, elements shown as integrally formed can be constructed of multiple parts or elements, the position of elements can be reversed or otherwise varied, and the nature or number of elements can be altered or varied. Thus, the foregoing description is not intended to be taken in a limiting sense, but is made solely for illustration rather than limitation. All such modifications are intended to be included within the scope of the present application. The order or sequence of any process or method steps can be varied or re-sequenced without departing from the subject matter described herein. Any "service" of the claims is intended to cover structures described herein that perform the function described in connection with such service. Other substitutions, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments without departing from the scope of the present application. Accordingly, the present application is not limited to the specific embodiments described herein, but extends in scope to other embodiments that will be readily apparent to those skilled in the art in view of the teachings herein.

[0048] Furthermore, in order to provide a concise description of exemplary embodiments, not all features of an actual implementation can be described (i.e., those pertaining to the

[0049] It should be noted that the above-mentioned embodiments are only used to illustrate the technical solutions of the present application, not limit the present application. Although the present application is described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced by equivalents without departing from the spirit and scope of the present application, which should be covered by the claims of the present application.

Claims

1. A fiber orientation regulating shear screw for use in screw extrusion 3D printing, characterized by: It comprises a stepping motor (1), a motor base (9), a shaft coupling (10), a bearing (11), a shearing element (18), a supporting plate (12), a machine cylinder (13), a feeding device (2), a feeding pipe (3), a water cooling device (5), a heating device (6), a spray head (7) and a nozzle (8). The stepping motor (1) is installed on the motor base (9), the shearing element (18) comprises a rotating rod (16), a rod body (4) and a conical head (17), the rotating rod (16) is provided with a limiting boss (15), and the outer surface of the rod body (4) is distributed with main body threads (14). The shaft coupling (10) connects the output end of the stepping motor (1) and the rotating rod (16), the bearing (11) is arranged between the rotating rod (16) and the motor base (9), the machine cylinder (13) is arranged outside the rod body (4) of the shearing element (18), and the machine cylinder (13) is supported on the supporting plate (12). The feeding device (2) is communicated with the machine cylinder (13) through the feeding pipe (3), the machine cylinder (13) is sequentially provided with the water cooling device (5) and the heating device (6) outside, the machine cylinder (13) is connected with the spray head (7) at the end, the spray head (7) is provided with the nozzle (8) at the end, the conical head (17) extends into the spray head (7) and is arranged close to the nozzle (8).

2. The fiber orientation regulating shear screw for screw-extrusion 3D printing of claim 1, wherein: The rotating rod (16), the rod body (4) and the conical head (17) of the shearing element (18) are integrally formed.

3. The fiber orientation regulating shear screw for screw-extrusion 3D printing of claim 2, wherein: The main body threads (14) of the rod body (4) cover the feeding section, the compression section and the metering section, the shearing element (18) and the inner wall of the machine cylinder (13) form an annular gap, and the shearing force is generated in rotation to promote the orientation of fibers.

4. The fiber orientation regulating shear screw for screw extrusion 3D printing of claim 3, wherein: The limiting boss (15) is used for limiting the axial displacement of the shearing element (18), and the bearing (11) is in rotating fit with the outer wall of the rotating rod (16).

5. The fiber orientation regulating shear screw for screw extrusion 3D printing of claim 4, wherein: One end of the feeding pipe (3) is communicated with the discharge port of the feeding device (2), the other end is communicated with the feeding area of the machine cylinder (13), and the feeding section of the rod body (4) is arranged.

6. The fiber orientation regulating shear screw for screw extrusion 3D printing of claim 5, wherein: The water cooling device (5) and the heating device (6) are distributed along the axial direction of the machine cylinder (13) and are arranged corresponding to different functional sections of the rod body (4).

7. The fiber orientation regulating shear screw for screw extrusion 3D printing of claim 6, wherein: One end of the spray head (7) is sealingly connected with the end of the machine cylinder (13), and the other end is detachably connected with the nozzle (8).

8. The fiber orientation regulating shear screw for screw extrusion 3D printing of claim 7, wherein: The supporting plate (12) is fixedly connected with the outer wall of the machine cylinder (13) and is used for supporting the machine cylinder (13) to maintain a predetermined installation posture.

9. The fiber orientation regulating shear screw for screw extrusion 3D printing of claim 8, wherein: The two ends of the shaft coupling (10) are fixedly connected with the output shaft of the stepping motor (1) and the end of the rotating rod (16) respectively, so as to realize power transmission.

10. The fiber orientation regulating shear screw for screw extrusion 3D printing of claim 9, wherein: The conical head (17) of the shearing element (18) is conical, the end thereof is close to the discharge port of the nozzle (8), and is used for guiding the material to flow to the nozzle (8).

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