A desktop carbon fiber printing device and its post-processing algorithm

Abstract

A desktop carbon fiber printing device and its post-algorithm belong to the technical field of three-dimensional printing equipment, including a base and a three-axis slide rail system, a U-axis rotation mechanism and a workbench are movably installed on the three-axis slide rail system, a thermoplastic wire-laying printing mechanism is installed on the U-axis rotation mechanism, and the thermoplastic wire-laying printing mechanism is located above the workbench. The thermoplastic wire-laying printing mechanism includes a mounting plate fixedly installed on the U-axis rotation mechanism, a hot air blower is installed on the mounting plate, and a material tray assembly, a guide assembly, a wire feeding assembly, a shearing mechanism and a pressure roller assembly are arranged on one side of the hot air blower from top to bottom. A wire feeding nozzle is installed at the lower part of the mounting plate, and the wire feeding nozzle is arranged opposite to the pressure roller assembly. The air supply nozzle of the hot air blower is close to the wire feeding nozzle, and an FDM print head is installed on the back of the mounting plate. The printing device has multiple degrees of freedom. With the use of the hot air blower, thermoplastic treatment is directly performed during wire laying without secondary curing, thereby avoiding the use of large-scale thermosetting equipment. The device is suitable for use in laboratories and other scenarios.

Description

Technical Field

[0001] The invention relates to the technical field of three-dimensional printing equipment, and in particular to a desktop carbon fiber printing equipment and a post-processing algorithm thereof. Background Art

[0002] As a high-strength, high-modulus, low-density fiber-reinforced material, carbon fiber can be combined with 3D printing technology to produce three-dimensional entities with excellent mechanical properties. Traditional carbon fiber printers use FDM printing.

[0003] However, the nozzle diameter of FDM is small, and carbon fiber composite materials have the characteristics of high strength, high modulus and poor fluidity, which makes the printing speed lower than 10mm / s, the printing flux is very low, and the printing requires a high heating temperature, which seriously limits the promotion and application of carbon fiber composite 3D printing products. Wire laying technology is often used to increase the printing speed of carbon fiber products, but currently most of the wire laying equipment is large equipment using a thermosetting process. The equipment is large and expensive, and after laying, the carbon fiber products need to be put into an autoclave for secondary curing, which is energy-consuming and time-consuming.

[0004] At present, the problem of wire laying and thermosetting is generally solved by thermoplastic process. However, the existing thermoplastic wire laying mostly adopts laser as heat source and uses large robots as motion platform. The overall footprint is large and it is difficult to use in laboratories and other places. In addition, the printing materials cannot be laid in an interlaced manner, and the overall structural strength of the printed products is low, and the material utilization rate is low. Moreover, due to the large modulus of carbon fiber, sudden tension changes are very likely to occur during the wire laying process, which affects the printing reliability and printing accuracy, resulting in poor printing quality. Summary of the invention

[0005] In order to solve the technical problems in the above-mentioned background technology that the existing thermoplastic fiber placement equipment occupies a large area as a whole, is difficult to use in laboratories and other places, and has poor quality of printed products, the present invention provides a desktop carbon fiber printing device.

[0006] The technical solution of the present invention is as follows: The invention provides a desktop carbon fiber printing device, comprising a base, a three-axis slide rail system is installed on the base, a U-axis rotating mechanism and a workbench are movably installed on the three-axis slide rail system, a thermoplastic wire-laying printing mechanism is installed on the U-axis rotating mechanism, the thermoplastic wire-laying printing mechanism is located above the workbench, the thermoplastic wire-laying printing mechanism comprises a mounting plate fixedly installed on the U-axis rotating mechanism, a hot air blower is installed on the mounting plate, a material tray assembly, a guide assembly, a wire feeding assembly, a shearing mechanism and a pressure roller assembly are sequentially arranged on one side of the hot air blower from top to bottom, a wire feeding nozzle is installed at the lower part of the mounting plate, the wire feeding nozzle is arranged opposite to the pressure roller assembly, the air supply nozzle of the hot air blower is close to the wire feeding nozzle, and the mounting plate An FDM print head is installed on the back. The gantry-type four-axis structure is formed by the cooperation of the three-axis slide rail system and the U-axis rotation mechanism, so that the thermoplastic filament printing mechanism has four degrees of freedom in the X, Y, Z, and U directions. It can not only realize the flat printing of materials, but also complete the curved surface printing, such as curved plates, prosthetic supports, aircraft blades, gas tanks, etc. The overall structure is compact and occupies a small area. With the use of a hot air blower, thermoplastic treatment is directly carried out during filament laying without secondary curing, avoiding the use of large-scale thermosetting equipment. It is suitable for laboratories and other scenarios, and can complete the curved surface laying of printing materials, increase the diversity of printing structures and the application scope of equipment, improve the competitiveness of equipment, and achieve high stability and high-precision printing of carbon fiber.

[0007] Preferably, the three-axis slide system includes a Y-axis slide mechanism and a Z-axis slide assembly fixedly mounted on a base, an X-axis slide mechanism being slidably connected to the Z-axis slide assembly, a workbench being slidably disposed on the Y-axis slide mechanism, a U-axis rotation mechanism being slidably disposed on the X-axis slide mechanism, an FDM material tray being mounted on the back of the X-axis slide mechanism, and forming a gantry-type four-axis structure together with the U-axis rotation mechanism, so that the thermoplastic filament printing mechanism has four degrees of freedom in X, Y, Z, and U directions, which can not only realize flat printing of materials, but also complete curved surface printing, such as curved plates, prosthetic supports, aircraft blades, gas tanks, etc. The overall structure is compact, occupies a small area, and has a wider range of uses.

[0008] Preferably, the X-axis slide rail mechanism, the Y-axis slide rail mechanism and the Z-axis slide rail assembly are all ball screw driven structures, with high position adjustment control accuracy, which can ensure the printing quality of the printed product.

[0009] Preferably, the U-axis rotation mechanism includes a U-axis mounting seat slidably connected to the X-axis slide rail mechanism, a driving assembly is fixedly installed on the U-axis mounting seat, a turntable bearing and a connecting plate are connected in sequence below the driving assembly, and the mounting plate is fixedly installed on the connecting plate. The driving assembly drives the thermoplastic wire placement printer to rotate around the Z-axis. Combined with the use of the three-axis slide rail system, the thermoplastic wire placement printing mechanism has four degrees of freedom in X, Y, Z, and U directions, has a wide range of applications, and can realize the thermoplastic wire placement printing mechanism to rotate 180° around the Z-axis, thereby realizing the staggered laying of printing materials on the workbench, thereby improving the strength of the structure, increasing material utilization, and reducing the weight of the printed product.

[0010] Preferably, the material tray assembly includes a material tray support frame and a material tray. The material tray support frame is fixedly arranged on one side of the mounting plate. The material tray is rotatably connected to the material tray support frame through a one-way damping bearing. The one-way damping bearing is provided with an adjusting nut. The resistance of the material tray is adjusted by adjusting the nut. In conjunction with the guide wheel, guide plate and wire feeding wheel, the printing material has a stable tension force during the printing process. The structure is simple and effectively solves the problem of sudden tension change caused by the large modulus of carbon fiber, thereby ensuring the reliability and printing accuracy of the printing process.

[0011] Preferably, the guide assembly includes a guide wheel and a guide plate which are rotatably arranged on the mounting plate in sequence from top to bottom, the wire feeding assembly includes a pressure wheel and a wire feeding wheel which are relatively arranged, the wire feeding wheel is connected to a wire feeding motor, the pressure wheel is connected to a transversely arranged pressure wheel cylinder, a shearing plate is fixedly provided below the wire feeding wheel, the plate surface of the shearing plate is perpendicular to the mounting plate, the shearing mechanism is connected to a transversely arranged shearing cylinder, the shearing mechanism and the shearing plate are arranged relatively to each other, and are used for positioning, pressing and shearing the printing material.

[0012] Preferably, the shearing mechanism includes a movable knife plate connected to the shear cylinder, a hollow shearing top block is fixedly provided on the movable knife plate, a shearing column and a shearing tool are laterally provided in the shearing top block, the shearing column and the shearing tool both extend outward at one end close to the shearing plate, the shearing column is slidably connected to the shearing top block, one end of the shearing column is connected to the inner wall of the shearing top block by a spring, the shearing tool is fixedly connected to the inner wall of the shearing top block, and the shearing column can press the printed material at the shearing tool to facilitate cutting and ensure the flatness of the cutting position.

[0013] Preferably, a turntable mechanism is installed on the workbench, and the turntable mechanism includes a turntable supporting seat fixedly installed on the workbench, a first turntable is rotatably provided on the turntable supporting seat, a second turntable is rotatably provided on the first turntable, the axial direction of the rotating shaft of the first turntable is perpendicular to the second turntable, and the axial direction of the rotating shaft of the first turntable is parallel to the Y-axis slide rail mechanism, the axial direction of the rotating shaft of the second turntable is parallel to or has an angle with the Z-axis slide rail assembly, the rotating shafts of the first turntable and the second turntable are respectively connected to a B-axis motor and a C-axis motor, and in conjunction with the arrangement of the Y-axis slide rail mechanism, the Z-axis slide rail assembly, the X-axis slide rail mechanism and the U-axis rotating mechanism, the entire printing device has six degrees of freedom to complete the curved surface laying of the printing material, increase the diversity of the printing structure and the application scope of the equipment, and improve the competitiveness of the equipment.

[0014] The present invention provides a post-processing algorithm, which is as follows: when the turntable mechanism (57) is not added, the trajectory V in the feeding direction is directly i+1 Projecting onto the XY plane gives the vector V xy i+1 , solve for V in the XY plane xy init With V xy i+1 Angle , the initial state of the printing device obtains the initial orientation of the pressure roller (44) as V xy init , V xy init is the -X axis direction, Depend on To obtain, and The calculation formula is:

[0015]

[0016] in, , They are vector V xy init 、V xy i+1 In the x-axis coordinate component, pi is 180° which corresponds to radians.

[0017] Preferably, when adding the turntable mechanism (57), first perform normal post-processing according to the BC axis five-axis machine tool to calculate the current tool position point P i+1 Normal vector n i+1 The angle of the BC axis when it is parallel to the Z axis , , then based on the BC angle, calculate V after swing xy i+1 The real space vector , the real space vector The calculation formula is:

[0018] Then Projecting onto the XY plane gives the vector , solve for V in the XY plane xy init and Angle , angle This is the rotation angle of the U axis during 3D printing.

[0019] It can be seen from the above technical solutions that the advantages of the present invention are: 1. Combine the application of carbon fiber material laying with 3D printing technology. Through the cooperation of the three-axis slide rail system and the U-axis rotation mechanism to form a gantry four-axis structure, the thermoplastic wire laying printing mechanism has the freedom of four directions of X, Y, Z, and U. It can not only realize the flat printing of materials, but also complete the curved surface printing. The overall structure is compact and occupies a small area. With the use of hot air blower, thermoplastic treatment is directly carried out during wire laying without secondary curing, avoiding the use of large-scale thermosetting equipment. It is suitable for use in laboratories and other scenarios, and can complete the curved surface laying of printing materials, increase the diversity of printing structures and the application scope of equipment, improve the competitiveness of equipment, and achieve high stability and high-precision printing of carbon fiber.

[0020] 2. On the basis of realizing carbon fiber filament printing, an FDM print head is also installed, which can realize the printing of materials such as PLA, ABS, short fiber carbon fiber, PA, the filling of filament gaps, and the online production of core molds. Because the filament laying method is used for additive manufacturing, the width of the consumables is increased, and the printing flux is significantly improved, making rapid carbon fiber manufacturing possible, effectively shortening the sample production time and improving the sample production efficiency. At the same time, the desktop design and hot air heating are adopted to reduce the equipment body, greatly reducing the equipment cost, making efficient carbon fiber printing more practical.

[0021] 3. The printing equipment can better combine the application of carbon fiber material laying with 3D printing technology. The entire printing equipment has six degrees of freedom: X, Y, Z, U, B, and C. The overall structure is compact and occupies a small area. It can also realize the 180° rotation of the thermoplastic filament printing mechanism around the Z axis, realizing the staggered laying of printing materials on the workbench, thereby improving the strength of the structure, increasing material utilization, and reducing the weight of printed products.

[0022] 4. The material tray is rotatably connected to the material tray support frame through a one-way damping bearing. An adjusting nut is provided on the one-way damping bearing. The resistance of the material tray is adjusted by adjusting the nut. In conjunction with the guide wheel, guide plate and wire feeding wheel, the printing material has a stable tension during the printing process. The structure is simple and effectively solves the problem of sudden tension caused by the large modulus of carbon fiber, ensuring the reliability and printing accuracy of the printing process.

[0023] 5. The printing equipment adopts a post-algorithm. During the wire laying printing process, the direction of the pressure roller can be made consistent with the wire feeding direction. It can be applied to different working conditions and meet the needs of printing equipment with six degrees of freedom of X, Y, Z, U, B, and C, effectively ensuring the printing quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solution of the present invention, the accompanying drawings required for use in the description will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0025] Figure 1 The overall structure of a desktop carbon fiber printing device according to one or more embodiments of the present invention is shown in FIG. Figure 1 ; Figure 2 The overall structure of a desktop carbon fiber printing device according to one or more embodiments of the present invention is shown in FIG. Figure 2 ; Figure 3 The overall structure of a desktop carbon fiber printing device according to one or more embodiments of the present invention is shown in FIG. Figure 3 ; Figure 4 It is a schematic diagram of the main structure of the U-axis rotation mechanism according to one or more embodiments of the present invention; Figure 5 It is a side view structural schematic diagram of a U-axis rotation mechanism according to one or more embodiments of the present invention; Figure 6 It is a schematic diagram of a top view of a U-axis rotation mechanism according to one or more embodiments of the present invention; Figure 7 It is a schematic diagram of the main structure of a thermoplastic filament printing mechanism according to one or more embodiments of the present invention; Figure 8 It is a schematic side view of the structure of a thermoplastic filament placement printing mechanism according to one or more embodiments of the present invention; Fig. 9 is a schematic structural diagram of a shearing mechanism according to one or more embodiments of the present invention; Fig.10is a schematic cross-sectional structure diagram of a shearing mechanism according to one or more embodiments of the present invention; Fig.11 The overall structure of a desktop carbon fiber printing device according to one or more embodiments of the present invention is shown in FIG. Figure 4 ; Fig.12 is a schematic diagram of a three-dimensional structure of a turntable mechanism according to one or more embodiments of the present invention; Fig.13 A schematic diagram of a top view of a turntable mechanism according to one or more embodiments of the present invention; The components represented by the reference numerals in the figure are: 1. Base; 2. Y-axis slide mechanism; 3. Workbench; 4. First Z-axis slide mechanism; 5. X-axis slide mechanism; 6. Second Z-axis slide mechanism; 7. U-axis rotation mechanism; 8. Thermoplastic wire printing mechanism; 9. Y-axis slide; 10. Y-axis slider; 11. Y-axis ball screw; 12. Nut seat; 13. Column; 14. X-axis slide; 15. X-axis motor; 16. First coupling; 17. X-axis ball screw; 18. Z-axis slide; 19. Z-axis ball screw; 20. Z-axis motor; 21. Second coupling; 22. Support plate; 23. U-axis mounting seat; 24. X-axis slide; 25. Y-axis motor; 26. Reinforcement plate; 27. FDM tray; 28. Servo motor; 29. ​​Planetary reducer; 30. Turntable bearing; 31. Connecting plate; 32. Hot air blower; 33. Mounting plate ;34. Printing material;35. Material tray support frame;36. Adjusting nut;37. Material tray;38. Guide wheel;39. Mounting block;40. Guide plate;41. Pressure wheel cylinder;42. Pressure wheel;43. Pressure roller cylinder;44. Pressure roller;45. Shearing plate;46. Wire feeding nozzle;47. Shearing mechanism;48. Shearing cylinder;49. Wire feeding motor;50. Wire feeding wheel;51. FDM print head;52. Moving knife plate;53. Shearing top block;54. Shearing column;55. Shearing tool;56. Spring;57. Turntable mechanism;58. B-axis motor;59. First pulley;60. First belt;61. First turntable;62. Second turntable;63. C-axis mounting seat;64. C-axis motor;65. Second belt;66. Turntable support seat;67. Second pulley;68. B-axis mounting seat. DETAILED DESCRIPTION

[0026] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical scheme of the present invention will be clearly and completely described below in conjunction with the drawings in this specific embodiment. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of them. Based on the embodiments in this patent, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this patent.

[0027] Example 1 In a typical embodiment of the present invention, Figure 1-Figure 3 As shown, a desktop carbon fiber printing device is proposed, including: a base, a three-axis slide rail system, a workbench 3, a U-axis rotation mechanism 7 and a thermoplastic wire-laying printing mechanism 8, the three-axis slide rail system includes: a Y-axis slide rail mechanism 2, a first Z-axis slide rail mechanism 4, an X-axis slide rail mechanism 5, and a second Z-axis slide rail mechanism 6, wherein the Y-axis slide rail mechanism 2 is horizontally fixed on the base 1, the workbench 3 is installed on the Y-axis slide rail mechanism 2 through a nut seat 12, and the workbench 3 can move forward and backward along the Y-axis slide rail mechanism 2; the first Z-axis slide rail mechanism 4 and the second Z-axis slide rail machine 6 are relatively vertically fixed on the base 1, the first Z-axis slide rail mechanism 4 and the second Z-axis slide rail machine 6 are combined into a Z-axis slide rail assembly, and the Z-axis slide rail assembly as a whole is a dual-drive structure, and the wire-laying printing mechanism 8 is synchronously driven in the Z-axis direction through the combination of respective motors and ball screws. Ensure the stability and accuracy of the Z-axis movement of the equipment, and reduce the vibration and shaking of the equipment during high-speed operation; the X-axis slide mechanism 5 is horizontally installed on the first Z-axis slide mechanism 4 and the second Z-axis slide mechanism 6, and the X-axis slide mechanism 5 is perpendicular to the Y-axis slide mechanism 2, and a U-axis rotation mechanism 7 is slidably provided on the X-axis slide mechanism 5, and a thermoplastic wire-laying printing mechanism 8 is installed on the U-axis rotation mechanism 7. The thermoplastic wire-laying printing mechanism 8 can move left and right along the X-axis slide mechanism 5 and can rotate 180° around the Z axis under the action of the U-axis rotation mechanism 7 to form a gantry four-axis structure, so that the thermoplastic wire-laying printing mechanism 8 has four degrees of freedom in the X, Y, Z, and U directions (U here is the direction of rotation around the Z axis), which can not only realize plane printing of materials, but also complete curved surface printing, such as curved plates, prosthetic supports, aircraft blades, gas tanks, etc. like Figure 2 and Figure 3As shown, the Y-axis slide rail mechanism 2 includes a Y-axis slide rail 9, a Y-axis slider 10, a Y-axis ball screw 11 and a nut seat 12, the first Z-axis slide rail mechanism 4 and the second Z-axis slide rail mechanism 6 have the same structure, the first Z-axis slide rail mechanism 4 and the second Z-axis slide rail mechanism 6 both include a column 13, a Z-axis slide rail 18, a Z-axis ball screw 19 and a Z-axis motor 20, the X-axis slide rail mechanism 5 includes an X-axis slide rail 14, an X-axis motor 15, an X-axis ball screw 17, a support plate 22 and an X-axis slider 24, wherein the Y-axis slide rail 9 is provided with two The two Y-axis slide rails 9 are relatively horizontally fixedly arranged on the base 1, the two sides of the bottom of the workbench 3 are respectively fixedly connected with a Y-axis slider 10, and are slidably connected with the Y-axis slide rail 9 through the Y-axis slider 10, and the middle position of the bottom of the workbench 3 is fixedly connected with the nut seat 12, the nut seat 12 is threadedly connected with the Y-axis ball screw 11, and the Y-axis ball screw 11 is connected with the Y-axis motor 25 through a coupling, and the Y-axis motor 25 is fixedly arranged on the base 1, so as to realize the reciprocating movement of the workbench 3 along the Y-axis slide rail 9; The column 13 is vertically fixed on the base 1. There are two columns 13. The two columns 13 are arranged opposite to each other, and the two columns 13 are located on one side of the Y-axis slide rail mechanism 2. The bottom of the column 13 is fixedly connected to the base 1 through a reinforcing plate 26 to improve the rigidity and stability of the column 13. A Z-axis slide rail 18 is fixedly provided on the column 13. The Z-axis slide rail 18 extends along the length direction of the column 13. The Z-axis ball screw 19 is vertically installed on the column 13. The Z-axis motor 20 is fixedly provided on the top of the column 13, and the Z-axis ball screw 19 is fixedly connected to the output end of the Z-axis motor 20 through a second coupling 21. Screw nuts are fixedly installed on the left and right sides of the back of the support plate 22. The support plate 22 is threadedly connected to the Z-axis ball screws 19 on the two columns 13 through the screw nuts, and the support plate 22 is also slidably connected to the Z-axis slide rail 18 through a slider, and the support plate 22 can move up and down along the Z-axis slide rail 18; An FDM material tray 27 is also fixedly installed on the back of the support plate 22, an X-axis ball screw 17 is fixedly installed on the front of the support plate 22, the X-axis ball screw 17 is connected to the X-axis motor 15 through the first coupling 16, and the X-axis motor 15 is fixedly installed on the support plate 22. An X-axis slide rail 14 is fixedly installed on the upper and lower sides of the front of the support plate 22, and a screw nut is fixedly provided on the back of the X-axis slide plate 24. The back of the X-axis slide plate 24 is threadedly connected to the X-axis ball screw 17 through the screw nut. Slide blocks are also fixed on the upper and lower sides of the back side of the X-axis skateboard 24. The X-axis skateboard 24 is slidably connected to the X-axis slide rail 14 through the slide blocks. The X-axis skateboard 24 can move left and right along the X-axis slide rail 14. A U-axis rotation mechanism 7 is installed on the front side of the X-axis skateboard 24, which is connected to the thermoplastic wire-laying printing mechanism 8 through the U-axis rotation mechanism 7 to realize the rotation of the thermoplastic wire-laying printing mechanism 8 around the Z-axis (in order to distinguish the horizontal movement of the Z-axis, the rotation of the thermoplastic wire-laying printing mechanism 8 around the Z-axis direction is called U-axis rotation in this embodiment).

[0028] like Figure 4 , Figure 5 and Figure 6 As shown, the U-axis rotating mechanism 7 includes a U-axis mounting seat 23, a servo motor 28, a planetary reducer 29, a turntable bearing 30 and a connecting plate 31, wherein the U-axis mounting seat 23 is fixedly mounted on the X-axis slide plate 24 by bolt connection, a driving assembly is fixedly mounted above the U-axis mounting seat 23, and the driving assembly includes a planetary reducer 29, the upper part of the planetary reducer 29 is connected to the servo motor 28, and the turntable bearing 30 is rotatably mounted below the U-axis mounting seat 23, and the turntable bearing 30 is fixedly connected to the output end of the planetary reducer 29. Then, the connecting plate 31 is located below the turntable bearing 30 and is fixedly connected to the output end of the planetary reducer 29. A thermoplastic wire-placing printing mechanism 8 is fixedly installed on the connecting plate 31. The servo motor 28 can drive the turntable bearing 30 to rotate, thereby driving the connecting plate 31 and the thermoplastic wire-placing printing mechanism 8 installed on the connecting plate 31 to rotate, thereby realizing a 180° rotation of the thermoplastic wire-placing printing mechanism 8 around the Z axis, realizing the staggered laying of the printing material on the workbench 3, improving the strength of the structure, increasing the material utilization rate, and reducing the weight of the printed product.

[0029] like Figure 7-Figure 8As shown, the thermoplastic wire-laying printing mechanism 8 includes a hot air blower 32, a mounting plate 33, a material tray assembly, a guide assembly, a wire feeding assembly, a pressure roller assembly and a shearing mechanism 47. The guide assembly includes a guide wheel 38 and a guide plate 40. Specifically, the mounting plate 33 is fixedly mounted on the connecting plate 31 by bolt connection. The hot air blower 32 is fixedly mounted on the upper part of the mounting plate 33. One side of the upper part of the mounting plate 33 is fixedly connected to the material tray assembly. The material tray assembly is used for storing and supplying printing materials 34. The material tray assembly includes a material tray support frame 35 and a material tray 37. The material tray support frame The material tray 37 is rotatably mounted on the material tray support frame 35. The material tray support frame 35 is rotatably connected to the material tray 37 via a one-way damping bearing. The one-way damping bearing is provided with an adjusting nut 36. The rotation resistance of the material tray 37 can be adjusted by adjusting the nut 36, thereby ensuring the stability of the tension and the printing accuracy during the printing and wire feeding. A mounting block 39 is fixedly mounted on the mounting plate 33. The mounting block 39 is located directly below the material tray assembly. A guide wheel 38 is rotatably mounted on the mounting block 39 to assist the printing material 34 in feeding the wire. The guide plate 40 is fixedly arranged on the mounting plate 33, and the guide plate 40 is located directly below the guide wheel 38, so as to guide the printing material 34 during the wire feeding process, avoid the deflection of the printing material 34 during the wire feeding process, and ensure the accuracy of the wire feeding position. The wire feeding assembly is mounted on the mounting plate 33, and the wire feeding assembly is located below the guide plate 40, and is used for wire feeding. The wire feeding assembly includes a relatively arranged pressure wheel 42 and a wire feeding wheel 50. The pressure wheel 42 is rotatably arranged at the telescopic end of the pressure wheel cylinder 41, and the pressure wheel cylinder 41 can change the pressure wheel 42 and the wire feeding wheel 50. The distance between the wire feeding wheels 50, the pressure wheel cylinder 41 is laterally fixed on the mounting plate 33, the wire feeding wheel 50 is rotatably set on the mounting plate 33 and is connected to the output shaft of the wire feeding motor 49, and can drive the rotation of the wire feeding wheel 50 through the wire feeding motor 49, and the wire feeding motor 49 is fixedly mounted on the mounting plate 33; the pressure roller assembly is installed at the lower part of the mounting plate 33 and is located below the wire feeding assembly for rolling the printing material 34, and the shearing mechanism 47 is installed on the mounting plate 33 and is located between the wire feeding assembly and the pressure roller assembly for shearing the printing material 34.

[0030] Specifically, the pressure roller assembly includes a pressure roller cylinder 43 and a pressure roller 44. The pressure roller cylinder 43 is vertically fixed on the mounting plate 33. The pressure roller cylinder 43 is located below the pressure wheel cylinder 41. The pressure roller 44 is rotatably arranged at the telescopic end of the pressure roller cylinder 43. The vertical position of the pressure roller 44 can be changed by the pressure roller cylinder 43, thereby realizing the rolling of the printing material 34. A shearing plate 45 is provided below the wire feeding wheel 50. The shearing plate 45 is vertically fixed on the mounting plate 33. The plate surface of the shearing plate 45 is perpendicular to the mounting plate 33, so as to cooperate with the shearing mechanism 47 to realize the cutting of the printing material 34.

[0031] The shearing mechanism 47 is fixedly connected to the telescopic end of the shearing cylinder 48, and the shearing cylinder 48 is fixedly installed on the mounting plate 33 in a transverse direction, so that the shearing mechanism 47 can be driven to move transversely by the shearing cylinder 48, and then the shearing mechanism 47 and the shearing plate 45 can be used to cooperate to cut the printed material 34. The shearing mechanism 47 and the shearing plate 45 are arranged relative to each other, such as Figure 9-10 As shown, the shearing mechanism 47 includes a movable blade 52, a shearing top block 53, a shearing column 54, a shearing tool 55 and a spring 56, wherein the movable blade 52 is fixedly connected to the telescopic end of the shearing cylinder 48, the shearing top block 53 is fixedly arranged on the movable blade 52, the shearing top block 53 is a hollow structure, the shearing column 54 and the shearing tool 55 are both transversely arranged in the shearing top block 53, and the ends of the shearing column 54 and the shearing tool 55 close to the shearing deck 45 are both extended outward from the shearing top block 53, wherein the shearing column 54 and the shearing top block 53 slide The shear tool 55 is fixedly connected to the shear top block 53, and at least two shear columns 54 are provided, which are relatively distributed on the upper and lower sides of the shear tool 55 to press the printing material 34 on the upper and lower sides of the shear tool 55 to facilitate cutting and ensure the flatness of the cutting position. The spring 56 is also installed in the shear top block 53, and the end of the shear column 54 away from the shear deck 45 is connected to the spring 56, so that the shear column 54 can compress the spring 56 to slide into the inside of the shear top block 53, and can automatically reset under the action of the spring 56.

[0032] The specific principle of the shearing mechanism 47 is as follows: when the shearing cylinder 48 drives the movable blade 52 to move toward the direction close to the shearing plate 45, the shearing mechanism 47 moves as a whole, and the shearing column 54 presses the printing material 34 onto the shearing auxiliary plate 45. When the movable blade 52 continues to move toward the direction close to the shearing plate 45, the shearing column 54 compresses the spring 56, and the position no longer changes to maintain the pressure on the printing material 34. The shearing tool 55 will continue to move toward the direction close to the shearing plate 45 to cut the printing material and complete the wire feeding function.

[0033] It should be noted that, in the non-cutting working state, the extended end of the shearing post 54 is not shorter than the extended end of the shearing tool 55 to avoid the shearing tool 55 first contacting the printing material 34 before compacting the printing material 34 .

[0034] A wire feeding nozzle 46 is provided below the shearing mechanism 47. The wire feeding nozzle 46 is fixedly arranged at the lower part of the mounting plate 33, and the wire feeding nozzle 46 is arranged opposite to the pressure roller assembly. The air supply nozzle of the hot air blower 32 is close to the wire feeding nozzle 46. The wire feeding nozzle 46 completes the wire feeding and laying work by cooperating with the hot air blower 32 and the pressure roller assembly. A print head is fixedly installed on the back of the lower part of the mounting plate 33. The print head is an FDM print head 51, and an FDM material tray 27 is rotatably installed on the back of the support plate 22 of the X-axis slide rail mechanism 5, which can realize the printing of materials such as PLA, ABS, short fiber carbon fiber, PA, etc., so as to expand the scope of use of the printing equipment.

[0035] The printing device in this embodiment, on the basis of realizing carbon fiber filament printing, is also equipped with an FDM print head 51, which can realize the printing of materials such as PLA, ABS, short fiber carbon fiber, PA, and the filling of filament gaps and the online production of core molds. Since the filament laying method is adopted for additive manufacturing, the width of the consumables used is generally 12.7mm, 6.35mm or 3.175mm, the thickness is 0.15mm, the laying speed is generally greater than 20mm / s, the bandwidth is 6.35mm, and the printing flux is greater than 19.05 mm^3 / s. If a special thickened prepreg tape is used, the printing flux can be significantly improved, making rapid manufacturing of carbon fiber possible, effectively shortening the sample production time, and improving the sample production efficiency. At the same time, the desktop design and hot air heating are adopted to reduce the equipment body, greatly reduce the equipment cost, and make efficient carbon fiber printing more practical.

[0036] like Fig.11 As shown, a turntable mechanism 57 is installed on the workbench 3, which cooperates with the Y-axis slide mechanism 2, the Z-axis slide assembly, the X-axis slide mechanism 5 and the U-axis rotation mechanism 7, so that the entire printing device has six degrees of freedom to complete the curved surface laying of the printing material, increase the diversity of the printing structure and the application scope of the equipment, and improve the competitiveness of the equipment.

[0037] Specific as Figure 12-13As shown, the turntable mechanism 57 includes a turntable support seat 66, a B-axis motor 58, a C-axis motor 64, a first turntable 61 and a second turntable 62. The turntable support seat 66 is fixedly installed on the workbench 3. The turntable support seat 66 is a U-shaped structure. The two ends of the first turntable 61 are rotatably connected with the two vertical side walls of the turntable support seat 66 through a rotating shaft, and the axial direction of the rotating shaft of the first turntable 61 is parallel to the axial direction of the Y-axis slide rail mechanism 2. The second turntable 62 is rotatably arranged on the first turntable 61 through the rotating shaft. A B-axis motor 58 is fixedly installed on one vertical side wall of the turntable support seat 66. The B-axis motor 58 is fixedly mounted on the B-axis mounting seat 68. The output end of the B-axis motor 58 is connected to the rotating shaft of the first turntable 61 through a first pulley assembly. The first pulley assembly includes a first pulley 59 and a first belt 60. A first pulley 59 is fixedly mounted on the output end of the B-axis motor 58 and the rotating shaft of the first turntable 61, respectively. The two first pulleys 59 are connected by the first belt 60, so that the first turntable 61 can be rotated around the Y-axis direction under the drive of the B-axis motor 58 (in order to distinguish the horizontal movement of the Y-axis, this embodiment In the embodiment, the rotation of the first turntable 61 around the Y-axis direction is referred to as B-axis rotation); a C-axis mounting seat 63 is rotatably mounted on the other vertical side wall of the turntable support seat 66, and the C-axis mounting seat 63 is fixedly connected to the rotating shaft of the adjacent first turntable 61, and can rotate around the axis with the first turntable 61, and a C-axis motor 64 is fixedly mounted on the C-axis mounting seat 63, and the output end of the C-axis motor 64 is connected to the rotating shaft of the second turntable 62 through a second pulley assembly, and the second pulley assembly includes a second pulley 67 and a second belt 65, and the output end of the C-axis motor 64 and the second turntable A second pulley 67 is fixedly installed on the rotating shaft of 62, and the two second pulleys 67 are connected by a second belt 65, so that the second turntable 62 can rotate around its rotating shaft under the drive of the C-axis motor 64 (in this embodiment, it is called C-axis rotation, and the C-axis is parallel to the Z-axis or has an angle with it), so that the entire printing device has six degrees of freedom of X, Y, Z, U, B, and C. The overall structure is compact and occupies a small area. It can also complete the curved surface laying of printing materials, increase the diversity of printing structures and the application scope of the equipment, and improve the competitiveness of the equipment.

[0038] The working principle is as follows: before printing begins, the material tray 37 is mounted on the one-way damping bearing, and the set resistance is adjusted by adjusting the nut 36. The printing material 34 is manually passed through the guide wheel 38, the guide plate 40 and the wire feeding wheel 50, and is fed into the wire feeding nozzle 46 through the shearing auxiliary plate 45. At this time, the wire feeding motor 49 is not working, the pressure wheel cylinder 41 does not drive the pressure wheel 42 to move left, the shearing cylinder 48 does not drive the shearing mechanism 47 to move right, and the pressure roller cylinder 43 does not drive the pressure roller 44 to move downward. The resistance of the material tray 37 is adjusted by adjusting the nut 36, and the guide wheel 38, the guide plate 40 and the wire feeding wheel 50 are matched to make the printing material 34 have a stable tension during the printing process. The structure is simple and effectively solves the problem of sudden tension caused by the large modulus of carbon fiber, ensuring the reliability and printing accuracy of the printing process. At the beginning of printing, the hot air blower 32 works, the wire feeding motor 49 starts to drive the wire feeding wheel 50 to rotate, and the pressure wheel cylinder 41 drives the pressure wheel 42 to move left, and the two cooperate to complete the wire feeding; during normal printing, the hot air blower 32 works, the wire feeding motor 49 drives the wire feeding wheel 50 to work normally, the pressure wheel cylinder 41 drives the pressure wheel 42 to move right, and the pressure roller cylinder 43 drives the pressure roller 44 to move down, and rolls the printing material 34; when printing is completed, the wire feeding motor 49 stops working, the shearing cylinder 48 drives the shearing mechanism 47 to move right, and the two shearing columns 54 in the shearing mechanism 47 press the printing material 34 on the shearing auxiliary plate 45, and the shearing cylinder 48 continues to drive the shearing mechanism 47 to move right. At this time, the shearing tool 55 cuts the printing material 34, and the printing material below continues to be laid; when working again, the shearing cylinder 48 drives the shearing mechanism 47 to move left, executes the work at the beginning of printing, and executes the subsequent steps.

[0039] The printing device in this embodiment can better combine the application of carbon fiber material laying with 3D printing technology. The entire printing device has six degrees of freedom, namely X, Y, Z, U, B, and C. The overall structure is compact and occupies a small area. With the use of a hot air blower 32, thermoplastic treatment is directly performed during filament laying without the need for secondary curing, thus avoiding the use of large-scale thermosetting equipment. The device is suitable for use in laboratories and other scenarios, and can complete the curved surface laying of printing materials, increase the diversity of printing structures and the application scope of the equipment, improve the competitiveness of the equipment, and achieve high stability and high-precision printing of carbon fiber.

[0040] Example 2 In another typical embodiment of the present invention, a post-algorithm of a desktop carbon fiber printing device is proposed. The desktop carbon fiber printing device in Example 1 supports wire laying printing using trajectories generated by conventional CAM software (such as UG, CATIA). Unlike milling processing, the direction of the pressure roller 44 during the wire laying printing process must be consistent with the wire feeding direction. Because there are restrictions on the wire feeding direction and the rolling direction of the pressure roller 44 during wire laying, the direction of the pressure roller 44 must be consistent with the feed direction during wire laying (the direction of the pressure roller 44 is the opposite of the projection of the wire feeding direction on the XY plane).

[0041] In order to realize the control of the direction of the pressure roller 44, it is necessary to first obtain the trajectory of the feeding direction, P i , P i+1 The first and last points on a certain rail section on the rail, through P i , P i+1 Available from P i Point to P i+1 Vector V i+1 =P i+1 -P i , combined with the initial state of the printing device, the initial orientation of the pressure roller 44 is obtained as V xy init , V xy init It is the -X axis direction.

[0042] When the BC axis attachment (i.e., the turntable mechanism 57) is not added, V i+1 Projecting onto the XY plane gives the vector V xy i+1 , solve for V in the XY plane xy init With V xy i+1 Angle , angle That is the rotation angle of the U axis during 3D printing. can be Seek, seek Finally, the shortest path optimization should be performed based on the swing angle value corresponding to the previous tool position:

[0043]

[0044] in , They are vector V xy init 、V xy i+1 In the X-axis coordinate component, pi is 180°, which corresponds to the radian system (i.e. ).

[0045] When adding BC axis accessories, the normal post-processing should be performed according to the BC axis five-axis machine tool to calculate the current tool position P. i+1 Normal vector n i+1 The angle of the BC axis when it is parallel to the Z axis , , then based on the BC angle, calculate the swing ( Point P i Point to P i+1 vector) real space vector , the calculation formula is: .

[0046] The formula means that the vector First rotate around the Z axis, the rotation angle is Then rotate around the Y axis, the rotation angle is .

[0047] Then Projecting onto the XY plane gives the vector , solve for V in the XY plane xy init and Angle , angle This is the rotation angle of the U axis during 3D printing.

[0048] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A desktop carbon fiber printing device, comprising: The base (1) is characterized in that a three-axis slide rail system is installed on the base (1), a U-axis rotation mechanism (7) and a workbench (3) are movably installed on the three-axis slide rail system, a thermoplastic wire-laying printing mechanism (8) is installed on the U-axis rotation mechanism (7), the thermoplastic wire-laying printing mechanism (8) is located above the workbench (3), the thermoplastic wire-laying printing mechanism (8) comprises a mounting plate (33) fixedly mounted on the U-axis rotation mechanism (7), a hot air blower (32) is mounted on the mounting plate (33), a material tray assembly, a guide assembly, a wire feeding assembly, a shearing mechanism (47) and a pressure roller assembly are sequentially arranged on one side of the hot air blower (32) from top to bottom, a wire feeding nozzle (46) is installed at the bottom of the mounting plate (33), the wire feeding nozzle (46) is arranged opposite to the pressure roller assembly, the air supply nozzle of the hot air blower (32) is close to the wire feeding nozzle (46), and an FDM print head (51) is installed on the back of the mounting plate (33).

2. The desktop carbon fiber printing device according to claim 1, characterized in that: The three-axis slide rail system comprises a Y-axis slide rail mechanism (2) and a Z-axis slide rail assembly fixedly mounted on a base (1); an X-axis slide rail mechanism (5) is slidably connected to the Z-axis slide rail assembly; a workbench (3) is slidably mounted on the Y-axis slide rail mechanism (2); a U-axis rotation mechanism (7) is slidably mounted on the X-axis slide rail mechanism (5); and an FDM material tray (27) is mounted on the back of the X-axis slide rail mechanism (5).

3. The desktop carbon fiber printing device according to claim 2, characterized in that: The X-axis slide rail mechanism (5), the Y-axis slide rail mechanism (2) and the Z-axis slide rail assembly are all ball screw drive structures.

4. The desktop carbon fiber printing device according to claim 1, characterized in that: The U-axis rotation mechanism (7) comprises a U-axis mounting seat (23) slidably connected to the X-axis slide rail mechanism (5); a driving assembly is fixedly mounted on the U-axis mounting seat (23); a turntable bearing (30) and a connecting plate (31) are sequentially connected below the driving assembly; the mounting plate (33) is fixedly mounted on the connecting plate (31); and the driving assembly drives the thermoplastic filament printer to rotate around the Z-axis.

5. The desktop carbon fiber printing device according to claim 1, characterized in that: The material tray assembly comprises a material tray support frame (35) and a material tray (37); the material tray support frame (35) is fixedly arranged on one side of the mounting plate (33); the material tray (37) is rotatably connected to the material tray support frame (35) via a one-way damping bearing; and an adjusting nut (36) is provided on the one-way damping bearing.

6. The desktop carbon fiber printing device according to claim 1, characterized in that: The guide assembly comprises a guide wheel (38) and a guide plate (40) which are rotatably arranged on a mounting plate (33) from top to bottom in sequence, the wire feeding assembly comprises a pressure wheel (42) and a wire feeding wheel (50) which are arranged opposite to each other, the wire feeding wheel (50) is connected to a wire feeding motor (49), the pressure wheel (42) is connected to a transversely arranged pressure wheel cylinder (41), a shearing plate (45) is fixedly arranged below the wire feeding wheel (50), the plate surface of the shearing plate (45) is perpendicular to the mounting plate (33), the shearing mechanism (47) is connected to a transversely arranged shearing cylinder (48), and the shearing mechanism (47) is arranged opposite to the shearing plate (45).

7. The desktop carbon fiber printing device according to claim 6, characterized in that: The shearing mechanism (47) comprises a movable blade (52) connected to a shearing cylinder (48), a hollow shearing top block (53) being fixedly provided on the movable blade (52), a shearing column (54) and a shearing tool (55) being transversely provided inside the shearing top block (53), the shearing column (54) and the shearing tool (55) both extending outward at one end close to the shearing deck (45), the shearing column (54) being slidably connected to the shearing top block (53), one end of the shearing column (54) being connected to the inner wall of the shearing top block (53) via a spring (56), and the shearing tool (55) being fixedly connected to the inner wall of the shearing top block (53).

8. The desktop carbon fiber printing device according to claim 1, characterized in that: A turntable mechanism (57) is installed on the worktable (3), and the turntable mechanism (57) includes a turntable support seat (66) fixedly installed on the worktable (3), a first turntable (61) is rotatably provided on the turntable support seat (66), a second turntable (62) is rotatably provided on the first turntable (61), the rotation axis of the first turntable (61) is perpendicular to the second turntable (62), and the rotation axis of the first turntable (61) is parallel to the Y-axis slide rail mechanism (2), and the rotation axis of the second turntable (62) is parallel to or has an angle with the Z-axis slide rail (18) component, and the rotation axes of the first turntable (61) and the second turntable (62) are respectively connected to a B-axis motor (58) and a C-axis motor (64).

9. A post-processing algorithm, characterized in that: Used in a desktop carbon fiber printing device as described in any one of claims 1 to 8, specifically as follows: when a turntable mechanism (57) is not added, the trajectory V of the feed direction is directly i+1 Projecting onto the XY plane gives the vector V xy i+1 , solve for V in the XY plane xy init With V xy i+1 Angle , the initial state of the printing device obtains the initial orientation of the pressure roller (44) as V xy init , V xy init is the -X axis direction, Depend on To obtain, and The calculation formula is: in, , They are vector V xy init 、V xy i+1 In the x-axis coordinate component, pi is 180° which corresponds to radians.

10. The post-processing algorithm according to claim 9, characterized in that: When adding the rotary table mechanism (57), first perform normal post-processing according to the BC axis five-axis machine tool to calculate the current tool position point P i+1 Normal vector n i+1 The angle of the BC axis when it is parallel to the Z axis , , then based on the BC angle, calculate V after swing xy i+1 The real space vector , the real space vector The calculation formula is: Then Projecting onto the XY plane gives the vector , solve for V in the XY plane xy init and Angle , angle This is the rotation angle of the U axis during 3D printing.

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