A multi-material rotary mixing 3D printing head device

Abstract

This invention belongs to the field of 3D printing technology, and specifically relates to a multi-material rotary mixing 3D printing head device, including a fixed base and a PLC controller fixedly mounted on the fixed base. Multiple guide cylinders are rotatably arranged on the fixed base, and a selection drive unit that cooperates with each guide cylinder is also provided on the fixed base. The selection drive unit is electrically connected to the PLC controller. This invention uses independently selectable rotary guide cylinders to pre-shear a single stream of slurry, effectively breaking up particle agglomerates. Simultaneously, the stirring blades initially rotate horizontally to centrifugally disperse the material, and then automatically switch to a vertical posture for reciprocating stirring, significantly improving the uniformity of multi-material mixing. Furthermore, the opening of the electronically controlled proportional valve is controlled in conjunction with viscosity and pressure detection, ensuring stable flow and pressure during the composite slurry extrusion process.

Description

Technical Field

[0001] This invention belongs to the field of 3D printing technology, and in particular relates to a multi-material rotary mixing 3D printing head device. Background Technology

[0002] Ink-to-ink 3D printing technology, as an important additive manufacturing method, extrudes functional slurries from the printhead and builds them up layer by layer. It has shown broad application prospects in fields such as biological tissue engineering, flexible electronics, and precision ceramic manufacturing. In the preparation of biological composite scaffolds, particle-reinforced composite materials, and functionally graded components, it is often necessary to mix various fluid slurries with different components in proportion online and then extrude and print them to obtain composite molded structures with adjustable composition and uniform performance.

[0003] However, in multi-material composite printing, existing ink-to-write 3D printing devices typically use fixed pipelines to directly feed various slurries into the mixing chamber for static mixing. Before entering the mixing chamber, the slurry is prone to particle agglomeration and clumping during static conveying, resulting in poor mixing after entering the mixing chamber. Furthermore, the statically conveyed slurry has a concentrated landing point, making it difficult to spread and mix quickly, leading to insufficient uniformity of the composite slurry and ultimately affecting the molding quality of multi-material composite printing.

[0004] To address the above problems, this invention provides a multi-material rotary mixing 3D printing head device. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a multi-material rotary mixing 3D printing head device to solve the problems in the prior art where static conveying of each slurry during multi-material composite printing easily leads to particle agglomeration, concentrated landing point after entering the mixing chamber, slow diffusion and mixing speed, insufficient mixing uniformity, and fluctuations in extrusion pressure and unstable discharge state caused by changes in slurry viscosity, which in turn affect the accuracy and molding quality of multi-material composite printing.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a multi-material rotary mixing 3D printing head device, including a fixed base and a PLC controller fixedly mounted on the fixed base, wherein multiple guide cylinders are rotatably arranged on the fixed base, and a selection drive unit that cooperates with each guide cylinder is provided on the fixed base, and the selection drive unit is electrically connected to the PLC controller;

[0007] A mixing seat is fixedly connected to the lower side of the fixed base, and the discharge end of each guide cylinder is rotatably connected to the mixing seat through the discharge pipe. The mixing seat is equipped with multiple attitude-adjustable stirring units, and each attitude-adjustable stirring unit cooperates and links with the corresponding discharge pipe. The attitude-adjustable stirring unit is electrically connected to the PLC controller.

[0008] A printing nozzle is fixedly connected to the lower side of the mixing seat. An electronically controlled proportional valve is provided at the feed end of the printing nozzle, and a pressure sensor is fixedly embedded in the inner wall of the feed end of the printing nozzle. Both the electronically controlled proportional valve and the pressure sensor are electrically connected to the PLC controller.

[0009] In the aforementioned multi-material rotary mixing 3D printing head device, the selection drive unit includes a servo motor, a drive gear, and multiple telescopic controllable auxiliary gears. The servo motor is fixedly mounted on a fixed base, and its output end extends into the fixed base and is fixedly sleeved with the drive gear. Each of the telescopic controllable auxiliary gears is fixedly sleeved with its corresponding guide cylinder. The servo motor and each telescopic controllable auxiliary gear are electrically connected to a PLC controller, and each telescopic controllable auxiliary gear can enter an extended state under the control of the PLC controller and mesh with the drive gear for transmission.

[0010] In the aforementioned multi-material rotary mixing 3D printing head device, the telescopic controllable secondary gear includes a rotating base and multiple tooth blocks. The rotating base is fixedly sleeved on the corresponding guide cylinder, and a groove that mates with the tooth blocks is provided on the rotating base. The tooth blocks are slidably connected to the corresponding grooves via sliders, and a return spring is fixedly provided between the slider and the corresponding groove. An electromagnetic block is fixedly embedded in the inner bottom surface of the groove, and a permanent magnet block corresponding to the electromagnetic block is fixedly embedded in the slider. The electromagnetic block is electrically connected to the PLC controller, and the electromagnetic block can generate magnetism and repel the corresponding permanent magnet block under the control of the PLC controller.

[0011] In the aforementioned multi-material rotary mixing 3D printing head device, the attitude-adjustable mixing unit includes a guide seat, a micro drive motor, a reciprocating screw, a guide rod, and two mixing blades. The guide seat is rotatably mounted on the mixing seat, and the guide seat and the corresponding discharge pipe are connected via a gear transmission assembly. A guide cavity is provided on the guide seat, and the reciprocating screw is rotatably mounted within the guide cavity. A guide block is threaded onto the reciprocating screw. A limit rod is fixedly installed in the guide cavity, and the guide block is slidably connected to the limit rod. One end of the reciprocating screw is connected to the micro drive motor. The system is dynamically connected, with the guide rod fixedly mounted on the guide block and slidably connected to the guide seat. The lower end of the guide rod extends into the mixing seat and is fixedly connected to an adjusting seat. The adjusting seat has a control cavity, and a rotating shaft is rotatably mounted in the control cavity. Both ends of the rotating shaft extend outside the adjusting seat and are fixedly connected to the corresponding stirring blades. A worm gear is rotatably mounted in the control cavity, and a worm wheel that meshes with the worm gear is fixedly sleeved on the rotating shaft. One end of the worm gear is driven by a micro stepper motor. Both the micro drive motor and the micro stepper motor are electrically connected to the PLC controller.

[0012] In the above-mentioned multi-material rotary mixing 3D printing head device, a level gauge is fixedly installed on the upper side of the mixing seat, and the detection end of the level gauge extends into the mixing seat. A viscosity detection probe is fixedly installed on the lower side of the adjusting seat. Both the level gauge and the viscosity detection probe are electrically connected to the PLC controller.

[0013] In the above-mentioned multi-material rotary mixing 3D printing head device, a heat dissipation shaft is fixedly installed on the guide seat and is rotatably connected to the fixed seat. The upper end of the heat dissipation shaft extends into the fixed seat and is fixedly connected to a heat dissipation fan blade. The heat dissipation fan blade is located directly below the meshing position of the corresponding telescopic controllable secondary gear and the active gear. The fixed seat has multiple heat dissipation holes, and a dustproof net is fixedly installed at the port of the heat dissipation hole.

[0014] In the above-mentioned multi-material rotary mixing 3D printing head device, a displacement sensor is fixedly installed in the guide cavity, and a sensing plate corresponding to the displacement sensor is fixedly embedded on the guide block. The displacement sensor is electrically connected to the PLC controller.

[0015] In the above-mentioned multi-material rotary mixing 3D printing head device, the inner wall of the guide cylinder is fixedly provided with spiral turbulence ribs, and the feed end of the guide cylinder is connected to the feed pipe through a rotary joint. The feed pipe is fixedly connected to the fixed base through a bracket, and the discharge pipe is provided with a solenoid valve, which is electrically connected to the PLC controller.

[0016] In the above-mentioned multi-material rotary mixing 3D printing head device, the lower side of the mixing seat has a conical structure design, and two mounting seats are fixedly installed on the upper side of the fixing seat.

[0017] Compared with existing technologies, the advantages of a multi-material rotary mixing 3D printing head device are:

[0018] 1. By setting up a selectable drive unit and multiple independently selectable guide cylinders, when multiple materials need to be combined, a specific guide cylinder can be engaged and driven by the selectable drive unit to rotate synchronously and actively. With the help of the spiral turbulence ribs inside the guide cylinder, continuous shearing is applied before the single-path slurry is delivered to the mixing seat, breaking up particle agglomerates and achieving homogeneous premixing of the single-path slurry to ensure the subsequent mixing effect. The guide cylinders not involved in the feeding remain stationary, reducing the energy consumption and mechanical wear of the transmission system. At the same time, through the independent selection control of each guide cylinder, the combination of materials involved in the mixing can be flexibly switched. With the flow control of the upstream conveying system, different ratios can be adjusted to meet the printing requirements of multi-component composite slurry.

[0019] 2. By setting up an adjustable stirring unit linked to the discharge pipe, the stirring blades maintain a horizontal posture in the initial stage of mixing, with a large receiving area. After the slurry falls onto the blade surface, it undergoes centrifugal diffusion as it rotates, and disperses into the mixing seat after detaching from the blade. This avoids the continuous accumulation of multiple slurries at their respective fixed landing points, allowing the slurries to form a spatially staggered distribution in the initial stage, thus accelerating the mixing speed. After the liquid level reaches the set position, the stirring blades automatically switch to a vertical posture and move up and down reciprocally, increasing the circumferential stirring contact area and reducing the longitudinal movement resistance. This stirs the slurry at different heights in the mixing seat, improving the uniformity of multi-material mixing.

[0020] 3. By setting up a viscosity detection probe, pressure sensor, electronic proportional valve and PLC controller for coordinated control, the viscosity and extrusion pressure of the mixed slurry can be sensed in real time. When the slurry viscosity increases and the flow resistance increases, the electronic proportional valve is automatically opened to reduce the extrusion resistance. When the viscosity decreases, it is automatically closed to prevent the material from being discharged too quickly. Based on this, the opening degree is finely adjusted in combination with the feedback of the pressure sensor to ensure the stability of the extrusion flow rate and pressure. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of a multi-material rotary mixing 3D printing head device provided by the present invention;

[0022] Figure 2 This is a front cross-sectional view of a multi-material rotary mixing 3D printing head device provided by the present invention;

[0023] Figure 3 This is a top-view cross-sectional view of the telescopic controllable secondary gear of a multi-material rotary mixing 3D printing head device provided by the present invention.

[0024] Figure 4 This is a front cross-sectional view of the attitude-adjustable stirring unit of a multi-material rotary mixing 3D printing head device provided by the present invention.

[0025] Figure 5 This is a front cross-sectional view of the adjustment seat of a multi-material rotary mixing 3D printing head device provided by the present invention.

[0026] Figure 6 This is a cross-sectional view of the material guide cylinder and the spiral baffle of a multi-material rotary mixing 3D printing head device provided by the present invention.

[0027] Figure 7 for Figure 3 Enlarged structural diagram at point A;

[0028] Figure 8 for Figure 4 A magnified structural diagram at point B in the middle.

[0029] In the diagram: 1. Fixed base; 2. PLC controller; 3. Guide cylinder; 4. Select drive unit; 4.1 Servo motor; 4.2 Drive gear; 4.3 Telescopic controllable auxiliary gear; 4.3.1 Rotary base; 4.3.2 Gear block; 5. Mixing seat; 6. Discharge pipe; 7. Attitude adjustable stirring unit; 7.1 Guide seat; 7.2 Micro drive motor; 7.3 Reciprocating screw; 7.4 Guide rod; 7.5 Stirring blade; 8. Printing nozzle; 9. Electrically controlled proportional valve; 10. Slide groove; 11. Slider; 12. Return spring; 13. Electromagnetic block; 14. Permanent magnet. 15. Gear transmission assembly, 16. Guide cavity, 17. Guide block, 18. Limiting rod, 19. Adjusting seat, 20. Control cavity, 21. Rotating shaft, 22. Worm gear, 23. Worm wheel, 24. Micro stepper motor, 25. Liquid level gauge, 26. Viscosity detection probe, 27. Heat dissipation shaft, 28. Heat dissipation fan blade, 29. Heat dissipation hole, 30. Displacement sensor, 31. Sensing plate, 32. Spiral baffle, 33. Rotary joint, 34. Feed pipe, 35. Bracket, 36. Solenoid valve, 37. Mounting base. Detailed Implementation

[0030] Specific embodiments of the present invention will now be described in detail. It should be noted that the embodiments described herein are for illustrative purposes only and are not intended to limit the invention. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that these specific details are not necessary to practice the invention. In other instances, well-known circuits, software, or methods have not been specifically described to avoid obscuring the invention.

[0031] like Figures 1-8 As shown, a multi-material rotary mixing 3D printing head device includes a fixed base 1 and a PLC controller 2 fixedly mounted on the fixed base 1. Multiple guide cylinders 3 are rotatably arranged on the fixed base 1, and a selection drive unit 4 that cooperates with each guide cylinder 3 is provided on the fixed base 1. The selection drive unit 4 is electrically connected to the PLC controller 2.

[0032] The drive unit 4 includes a servo motor 41, a drive gear 42, and multiple telescopic controllable auxiliary gears 43. The servo motor 41 is fixedly mounted on the fixed base 1, and its output end extends into the fixed base 1 and is fixedly sleeved with the drive gear 42. Each telescopic controllable auxiliary gear 43 is fixedly sleeved with the corresponding guide cylinder 3. The servo motor 41 and each telescopic controllable auxiliary gear 43 are electrically connected to the PLC controller 2. Each telescopic controllable auxiliary gear 43 can enter the unfolded state under the control of the PLC controller 2 and mesh with the drive gear 42. Through the cooperation between the telescopic controllable auxiliary gear 43 and the drive gear 42, the telescopic controllable auxiliary gear 43 of the corresponding guide cylinder 3 can be unfolded and meshed with the drive gear 42 under the control of the PLC controller 2, so as to realize the on-demand rotation of the guide cylinder 3, while the guide cylinder 3 that does not participate in feeding remains stationary, thereby reducing the no-load energy consumption and mechanical wear of the transmission system.

[0033] The telescopic controllable secondary gear 43 includes a rotating base 431 and multiple tooth blocks 432. The rotating base 431 is fixedly sleeved on the corresponding guide cylinder 3, and the rotating base 431 has a sliding groove 10 that cooperates with the tooth blocks 432. The tooth blocks 432 are slidably connected to the corresponding sliding groove 10 through a slider 11, and a return spring 12 is fixedly provided between the slider 11 and the corresponding sliding groove 10. An electromagnetic block 13 is fixedly embedded in the inner bottom surface of the sliding groove 10, and a permanent magnet block 14 corresponding to the electromagnetic block 13 is fixedly embedded in the slider 11. The electromagnetic block 13 is electrically connected to the PLC controller 2, and the electromagnetic block 13 can generate magnetism under the control of the PLC controller 2 to repel the corresponding permanent magnet block 14. The electromagnetic block 13 can use its own magnetic changes when it is energized and de-energized to control the telescopic state of the tooth blocks 432 in conjunction with the return spring 12 and the permanent magnet block 14, thereby controlling the meshing state of the telescopic controllable secondary gear 43 and the drive gear 42.

[0034] A mixing seat 5 is fixedly connected to the lower side of the fixed base 1, and the discharge ends of each guide cylinder 3 are rotatably connected to the mixing seat 5 through the discharge pipe 6. The discharge pipe 6 and the guide cylinder 3 are fixedly connected. A one-way waterproof and breathable valve is provided on the upper side of the mixing seat 5 to discharge the air in the cavity when the slurry enters the mixing seat 5. The mixing seat 5 includes a mixing cavity and a top cover. The mixing cavity and the top cover are detachably sealed and fixedly connected to facilitate disassembly and cleaning later. A spiral turbulence rib 32 is fixedly provided on the inner wall of the guide cylinder 3. The spiral turbulence rib 32 is composed of short ribs arranged in segments along the spiral path. The ends of each segment of short ribs are rounded. A gap is reserved between adjacent short ribs. This structure retains the axial pushing effect of the spiral turbulence rib 32, and forms a slurry pressure relief and flow channel through the segmented gaps to avoid local pressure accumulation and slurry jamming during the conveying process. At the same time, when the slurry flows through this structure, it will repeatedly undergo diversion, shearing and confluence. The process can further break up particle agglomerates, taking into account both the homogeneous premixing effect and conveying stability of the single-channel slurry. The feed end of the guide cylinder 3 is connected to the feed pipe 34 through the rotary joint 33. The feed pipe 34 is fixedly connected to the fixed base 1 through the bracket 35. The discharge pipe 6 is equipped with a solenoid valve 36, which is electrically connected to the PLC controller 2. The rotary joint 33 ensures that the rotation of the guide cylinder 3 is not obstructed. The rotary joint 33 is equipped with a sealing ring or wear-resistant sealing sleeve to ensure that the feed pipe 34 and the guide cylinder 3 remain sealed and connected when the guide cylinder 3 rotates. At the same time, the spiral turbulence ribs 32 cooperate with the rotating guide cylinder 3 to apply continuous shearing to the single-channel slurry during the slurry conveying stage, effectively breaking up particle agglomerates and achieving homogeneous premixing of the single-channel slurry. In addition, the solenoid valve 36 allows the PLC controller 2 to control the opening and closing of the corresponding discharge pipe 6 as needed.

[0035] Multiple adjustable stirring units 7 are provided on the mixing base 5, and each adjustable stirring unit 7 is linked with the corresponding discharge pipe 6. The adjustable stirring unit 7 is electrically connected to the PLC controller 2. The adjustable stirring unit 7 includes a guide seat 71, a micro drive motor 72, a reciprocating screw 73, a guide rod 74, and two stirring blades 75. The guide seat 71 is rotatably mounted on the mixing base 5, and the guide seat 71 and the corresponding discharge pipe 6 are connected by a gear transmission assembly 15. The guide seat 71 has a guide cavity 16, and the reciprocating screw 73 is rotatably mounted in the guide cavity 16. A guide block 1 is threadedly connected to the reciprocating screw 73. 7. A limit rod 18 is fixedly installed in the guide cavity 16, and the guide block 17 is slidably connected to the limit rod 18. One end of the reciprocating screw 73 is connected to the micro drive motor 72. The guide rod 74 is fixedly installed on the guide block 17, and the guide rod 74 is slidably connected to the guide seat 71. A linear sealed bearing is provided at the sliding fit between the guide rod 74 and the guide seat 71 to ensure smooth sliding and sealing. The lower end of the guide rod 74 extends into the mixing seat 5 and is fixedly connected to the adjusting seat 19. The adjusting seat 19 has a control cavity 20, and a rotating shaft 21 is rotatably installed in the control cavity 20. Both ends of the rotating shaft 21 extend outside the adjusting seat 19. A worm gear 22 is rotatably mounted in the control chamber 20, and a worm wheel 23 meshing with the worm gear 22 is fixedly sleeved on the rotating shaft 21. One end of the worm gear 22 is connected to a micro stepper motor 24. Both the micro drive motor 72 and the micro stepper motor 24 are electrically connected to the PLC controller 2. Conductive slip rings are provided on both the discharge pipe 6 and the guide seat 71 to provide power transmission to the electrical control components they carry during rotation. Through the cooperation of the reciprocating screw 73 and the micro drive motor 72, the guide block 17, together with the guide rod 74 and the stirring blade 75, can be driven to axially reciprocate and lift, thereby increasing... The longitudinal range of the large stirring blade 75 enables the stirring of slurry layers at different heights within the mixing seat 5. Through the combination of the worm gear 23 and worm 22 with the micro stepper motor 24, the rotating shaft 21 can be driven to rotate the stirring blade 75, allowing for flexible switching between horizontal and vertical postures. Furthermore, the self-locking characteristics of the worm gear 23 and worm 22 can lock the current posture after the stirring blade 75 has switched postures. The gear transmission assembly 15 enables the transmission connection between the guide seat 71 and the corresponding discharge pipe 6, allowing the rotational power of the stirring blade 75 to be directly derived from the rotational motion of the discharge pipe 6, thus avoiding the cost of adding additional drive equipment.

[0036] A displacement sensor 30 is fixedly installed inside the guide cavity 16, and a sensing plate 31 corresponding to the displacement sensor 30 is fixedly embedded on the guide block 17. The displacement sensor 30 is electrically connected to the PLC controller 2. By cooperating with the set displacement sensor 30 and sensing plate 31, the lifting position of the guide block 17 can be detected in real time, thereby monitoring the height of the stirring blade 75 in the mixing seat 5. After printing is completed, the PLC controller 2 can automatically shut down the micro drive motor 72 when the stirring blade 75 returns to the initial height according to the position signal fed back by the displacement sensor 30.

[0037] A heat dissipation shaft 27 is fixedly installed on the guide seat 71, and the heat dissipation shaft 27 is rotatably connected to the fixed seat 1. The upper end of the heat dissipation shaft 27 extends into the fixed seat 1 and is fixedly connected to a heat dissipation fan blade 28. The heat dissipation fan blade 28 is located directly below the meshing position of the corresponding telescopic controllable auxiliary gear 43 and the driving gear 42. The fixed seat 1 has multiple heat dissipation holes 29, and a dustproof screen is fixedly installed at the port of the heat dissipation hole 29. By using the heat dissipation shaft 27 in conjunction with the heat dissipation fan blade 28 and the heat dissipation holes 29, the heat dissipation fan blade 28 can be driven to rotate synchronously when the guide seat 71 rotates, so as to perform targeted air cooling on the meshing position of the telescopic controllable auxiliary gear 43 and the driving gear 42 located above it, and exhaust the heat from the heat dissipation holes 29. At the same time, the dustproof screen installed at the port of the heat dissipation hole 29 can prevent external dust from entering.

[0038] A printing nozzle 8 is fixedly connected to the lower side of the mixing base 5. A recovery pipe is also provided on the lower side of the mixing base 5, and a valve is installed on the recovery pipe to facilitate the recovery of residual slurry in the mixing base 5 later. An electronically controlled proportional valve 9 is provided at the feed end of the printing nozzle 8, and a pressure sensor is fixedly embedded in the inner wall of the feed end of the printing nozzle 8. The pressure sensor is located upstream of the electronically controlled proportional valve 9. Both the electronically controlled proportional valve 9 and the pressure sensor are electrically connected to the PLC controller 2. A level gauge 25 is fixedly installed on the upper side of the mixing base 5, and the detection end of the level gauge 25 extends into the mixing base 5. A viscosity detection probe 26 is fixedly installed on the lower side of the adjusting base 19. Both the level gauge 25 and the viscosity detection probe 26 are electrically connected to the PLC controller 2. The viscosity detection probe 26 is used to detect the viscosity of the material. The probe 26 works in conjunction with the pressure sensor. The PLC controller 2 uses the viscosity signal fed back by the viscosity detection probe 26 as feedforward to preset the basic opening of the electronically controlled proportional valve 9 to adapt to the current flow characteristics of the slurry. Based on this, the opening is finely adjusted according to the real-time pressure signal fed back by the pressure sensor, thereby taking into account the changes in flow resistance caused by viscosity changes and pressure fluctuations during the extrusion process, and maintaining the dual stability of extrusion flow and pressure. At the same time, the level gauge 25 is used to detect whether the slurry level has reached the preset height, so that the PLC controller 2 can control the stirring blade 75 to switch its posture accordingly. The viscosity detection probe 26 can move up and down synchronously with the adjusting seat 19 to detect the viscosity of the slurry at different heights, thereby improving the representativeness of the detection data.

[0039] The lower side of the mixing seat 5 has a conical structure design. The conical structure can guide the mixed slurry to gather towards the center and flow into the printing nozzle 8 below. Two mounting seats 37 are fixedly installed on the upper side of the fixed seat 1. This device is fixedly connected to the motion platform of the ink direct writing 3D printer through the two mounting seats 37 on the upper side of the fixed seat 1. Driven by the printer motion system, it forms a three-dimensional relative motion with the printing platform and completes the printing operation according to the preset path. Each feed pipe of the printer conveying system is connected to the corresponding feed pipe 34. The PLC controller 2 is electrically connected to the printer's main control system. The conveying ratio of each slurry is controlled by the upstream conveying system. Through the above cooperation, this device, as a modular printhead assembly of the printer, can receive and execute the instructions of the main control system to realize online selection, rotary premixing and collaborative extrusion of multiple materials.

[0040] The operating principle of the present invention is now described as follows:

[0041] When multiple pastes need to be mixed for printing, the printer's main control system sends a signal to the PLC controller 2. The PLC controller 2 controls the electromagnetic blocks 13 of the telescopic controllable secondary gear 43 on the corresponding guide cylinder 3 to be energized and magnetized. The energized electromagnetic blocks 13 repel the corresponding permanent magnet blocks 14, causing the teeth 432 of the telescopic controllable secondary gear 43 to extend, thereby causing the corresponding telescopic controllable secondary gear 43 to mesh with the drive gear 42 for transmission. The telescopic controllable secondary gears 43 corresponding to the other guide cylinders 3 that do not participate in the feeding process keep the teeth 432 in a retracted state and do not mesh with the drive gear 42.

[0042] Subsequently, the PLC controller 2 controls the opening of the solenoid valve 36 corresponding to the feed cylinder 3 that has intervened in the operation, and at the same time starts the servo motor 41. The servo motor 41 drives the drive gear 42 to rotate, and through the meshing telescopic controllable secondary gear 43, drives the feed cylinder 3 connected to the transmission to rotate synchronously. The various slurries conveyed upstream enter the corresponding feed cylinder 3 through the feed pipe 34, and then are discharged into the mixing seat 5 through the discharge pipe 6.

[0043] During the conveying process, the guide cylinder 3 rotates and cooperates with the internal spiral turbulence ribs 32 to form a continuous relative shear with the axially flowing slurry, breaking up the particle agglomerates inside the slurry, realizing the homogenization pretreatment of the single-path slurry, and enhancing the blending effect in the subsequent mixing process.

[0044] Under the transmission of the gear transmission assembly 15, the guide seat 71 corresponding to the discharge pipe 6 rotates synchronously, which in turn drives the stirring blade 75 to rotate through the guide rod 74. In the initial stage of mixing, the blade surface of the stirring blade 75 remains horizontal, with a large bearing area. After the slurry falls onto the blade surface, it undergoes centrifugal diffusion as it rotates, and disperses into the mixing seat 5 after detaching from the blade. This avoids the continuous accumulation of multiple slurries at their respective fixed landing points and accelerates the initial mixing speed. When the level gauge 25 detects that the liquid level in the mixing seat 5 has reached the set position and the liquid level completely submerges the stirring blade 75, the PLC controller 2 controls the micro stepper motor 24 to start, which drives the rotating shaft through the transmission of the worm gear 22 and the worm wheel 23. Rotate 21 to switch the blades of the two stirring blades 75 to a vertically downward posture. After the posture switch is completed, the PLC controller 2 turns off the micro stepper motor 24. At this time, since the blades of the stirring blades 75 are in a vertical posture, the circumferential stirring contact area of ​​the stirring blades 75 will increase, thereby improving the circumferential mixing effect. Then, the PLC controller 2 controls the micro drive motor 72 to start, driving the reciprocating screw 73 to rotate. Under the limiting action of the limit rod 18, the guide block 17 drives the stirring blades 75 to perform axial reciprocating lifting and lowering motion through the guide rod 74, expanding the longitudinal action range of the stirring. Moreover, the vertical posture of the stirring blades 75 can reduce the fluid resistance of longitudinal movement and improve the mixing effect.

[0045] When the pressure at the feed end of the print head 8 reaches the lower limit of the working range, the PLC controller 2 controls the electronic proportional valve 9 to open according to the feedback signal of the pressure sensor, so that the print head 8 completes a brief pre-discharge at the pre-extrusion station, expelling the stagnant air in the downstream flow channel of the electronic proportional valve 9, as well as the unstable slurry components that are prone to particle sedimentation near the discharge end of the print head 8. After the pre-discharge is completed, the PLC controller 2 closes the electronic proportional valve 9. After the printer main control system drive device moves to the printing start position, the PLC controller 2 opens the electronic proportional valve 9 again to start the formal printing.

[0046] During the printing process, the PLC controller 2 presets the basic opening of the electronically controlled proportional valve 9 based on the average viscosity signal fed back by the viscosity detection probe 26 per unit time. The higher the viscosity, the larger the basic opening to reduce the extrusion resistance of the slurry; the lower the viscosity, the smaller the basic opening to prevent excessively fast discharge. This ensures that the flow cross-section of the print head 8 is adapted to the current flow characteristics of the slurry. Based on this, the PLC controller 2 continuously reads the real-time values ​​of the pressure sensor. When the pressure deviates from the target range, it makes small adjustments to the electronically controlled proportional valve 9 based on the basic opening. If the pressure is too high, it opens slightly to reduce flow resistance and lower the upstream pressure. If the pressure is too low, it closes slightly to increase flow resistance and raise the upstream pressure. If the pressure cannot be restored to the normal range by adjusting the electronically controlled proportional valve 9 alone, it indicates that the current conveying force does not match the printing requirements. The PLC controller 2 then sends an instruction to the printer main control system to increase or decrease the conveying force of the printer conveying system to ensure the stability of the extrusion pressure and flow rate.

[0047] When the guide seat 71 rotates, it also drives the heat dissipation shaft 27 and the heat dissipation fan blades 28 to rotate, continuously cooling the meshing position of the telescopic controllable auxiliary gear 43 and the drive gear 42 in the working state. The heat is discharged through the heat dissipation holes 29 opened on the fixed seat 1, ensuring the reliability of the transmission components during long-term operation.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A multi-material rotary mixing 3D printing head device, comprising a fixed base (1) and a PLC controller (2) fixedly mounted on the fixed base (1), characterized in that, Multiple guide cylinders (3) are rotatably arranged on the fixed base (1), and a selection drive unit (4) that cooperates with each guide cylinder (3) is provided on the fixed base (1). The selection drive unit (4) is electrically connected to the PLC controller (2). The lower side of the fixed base (1) is fixedly connected to the mixing base (5), and the discharge end of each guide cylinder (3) is rotatably connected to the mixing base (5) through the discharge pipe (6). The mixing base (5) is provided with multiple attitude-adjustable stirring units (7), and each attitude-adjustable stirring unit (7) is coordinated with the corresponding discharge pipe (6). The attitude-adjustable stirring unit (7) is electrically connected to the PLC controller (2). The lower side of the mixing seat (5) is fixedly connected to the printing nozzle (8). The feeding end of the printing nozzle (8) is provided with an electronically controlled proportional valve (9), and a pressure sensor is fixedly embedded in the inner wall of the feeding end of the printing nozzle (8). The electronically controlled proportional valve (9) and the pressure sensor are both electrically connected to the PLC controller (2). The selection drive unit (4) includes a servo motor (41), a drive gear (42) and multiple telescopic controllable auxiliary gears (43). The servo motor (41) is fixedly mounted on the fixed base (1), and the output end of the servo motor (41) extends into the fixed base (1) and is fixedly sleeved with the drive gear (42). Each telescopic controllable auxiliary gear (43) is fixedly sleeved with the corresponding guide cylinder (3). The servo motor (41) and each telescopic controllable auxiliary gear (43) are electrically connected to the PLC controller (2), and each telescopic controllable auxiliary gear (43) can enter the unfolded state under the control of the PLC controller (2) and mesh with the drive gear (42) for transmission. The telescopic controllable secondary gear (43) includes a rotating base (431) and multiple tooth blocks (432). The rotating base (431) is fixedly sleeved on the corresponding guide cylinder (3), and the rotating base (431) is provided with a sliding groove (10) that cooperates with the tooth block (432). The tooth block (432) is slidably connected to the corresponding sliding groove (10) through a slider (11), and a return spring (12) is fixedly provided between the slider (11) and the corresponding sliding groove (10). An electromagnetic block (13) is fixedly embedded in the inner bottom surface of the sliding groove (10), and a permanent magnet block (14) corresponding to the electromagnetic block (13) is fixedly embedded in the slider (11). The electromagnetic block (13) is electrically connected to the PLC controller (2), and the electromagnetic block (13) can be energized and magnetized under the control of the PLC controller (2) to repel the corresponding permanent magnet block (14). The adjustable stirring unit (7) includes a guide seat (71), a micro drive motor (72), a reciprocating screw (73), a guide rod (74), and two stirring blades (75). The guide seat (71) is rotatably mounted on the mixing seat (5), and the guide seat (71) and the corresponding discharge pipe (6) are connected by a gear transmission assembly (15). The guide seat (71) has a guide cavity (16), and the reciprocating screw (73) is rotatably mounted in the guide cavity (16). A guide block (17) is threaded onto the reciprocating screw (73). A limit rod (18) is fixedly mounted in the guide cavity (16), and the guide block (17) is slidably connected to the limit rod (18). One end of the reciprocating screw (73) is connected to the micro drive motor (72), and the guide rod (74) is fixedly mounted on the guide cavity (75). The guide rod (74) is fixedly mounted on the guide block (17), and the guide rod (74) is slidably connected to the guide seat (71). The lower end of the guide rod (74) extends into the mixing seat (5) and is fixedly connected to the adjusting seat (19). The adjusting seat (19) has an adjustment cavity (20), and a rotating shaft (21) is rotatably mounted in the adjustment cavity (20). Both ends of the rotating shaft (21) extend outside the adjusting seat (19) and are fixedly connected to the corresponding stirring blade (75). A worm gear (22) is rotatably mounted in the adjustment cavity (20), and a worm wheel (23) meshing with the worm gear (22) is fixedly sleeved on the rotating shaft (21). One end of the worm gear (22) is connected to a micro stepper motor (24). The micro drive motor (72) and the micro stepper motor (24) are both electrically connected to the PLC controller (2).

2. The multi-material rotary mixing 3D printing head device according to claim 1, characterized in that, A level gauge (25) is fixedly installed on the upper side of the mixing seat (5), and the detection end of the level gauge (25) extends into the mixing seat (5). A viscosity detection probe (26) is fixedly installed on the lower side of the adjusting seat (19). Both the level gauge (25) and the viscosity detection probe (26) are electrically connected to the PLC controller (2).

3. The multi-material rotary mixing 3D printing head device according to claim 1, characterized in that, A heat dissipation shaft (27) is fixedly installed on the guide seat (71), and the heat dissipation shaft (27) is rotatably connected to the fixed seat (1). The upper end of the heat dissipation shaft (27) extends into the fixed seat (1) and is fixedly connected to a heat dissipation fan blade (28). The heat dissipation fan blade (28) is located directly below the meshing position of the corresponding telescopic controllable auxiliary gear (43) and the drive gear (42). The fixed seat (1) is provided with multiple heat dissipation holes (29), and a dustproof net is fixedly installed at the port of the heat dissipation hole (29).

4. The multi-material rotary mixing 3D printing head device according to claim 1, characterized in that, A displacement sensor (30) is fixedly installed in the guide cavity (16), and a sensing sheet (31) corresponding to the displacement sensor (30) is fixedly embedded on the guide block (17). The displacement sensor (30) is electrically connected to the PLC controller (2).

5. The multi-material rotary mixing 3D printing head device according to claim 1, characterized in that, The inner wall of the guide cylinder (3) is fixedly provided with spiral turbulence ribs (32), and the feed end of the guide cylinder (3) is connected to the feed pipe (34) through the rotary joint (33). The feed pipe (34) is fixedly connected to the fixed seat (1) through the bracket (35). The discharge pipe (6) is provided with a solenoid valve (36), and the solenoid valve (36) is electrically connected to the PLC controller (2).

6. The multi-material rotary mixing 3D printing head device according to claim 1, characterized in that, The lower side of the mixing seat (5) is designed with a conical structure, and two mounting seats (37) are fixedly installed on the upper side of the fixing seat (1).

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