A high-temperature hot bin type large 3D printing device

Abstract

The application discloses a high-temperature hot bin type large 3D printing device and relates to the technical field of 3D printing. The device comprises a bin, the inside of the bin is provided with a frame, the frame is used as a bearing component of the bin, the side of the frame is connected with a side plate, the side plate is embedded with a heating plate, the heating plate is used for heating the printing forming area inside the bin, the frame is slidably connected with a lifting platform, the lifting platform is driven by a driving mechanism, the driving mechanism comprises a Z-axis motor, the output end of the Z-axis motor is connected with a Z-axis screw rod, the Z-axis screw rod is threadedly connected with a Z-axis nut, and the Z-axis nut is connected to the lifting platform. Therefore, the existing 3D printing equipment adopts a cavity overall heating mode, the heating device needs to synchronously heat all air in the whole closed cavity, the cavity inner wall and the frame structure, the system has large overall heat capacity, and a long preheating time is needed for rising from normal temperature to the required temperature in the process.

Description

Technical Field

[0001] This invention relates to the field of 3D printing technology, and in particular to a high-temperature hot chamber type large-scale 3D printing device. Background Technology

[0002] Current 3D printing technology has developed into several mature process routes. Based on different forming principles and materials used, mainstream technologies include: Fused Deposition Modeling (FDM), which involves heating and extruding thermoplastic filaments to deposit layer by layer; Stereolithography / Deposition Laminate (SLA / DLP), which uses ultraviolet light to cure liquid photosensitive resin layer by layer; Selective Laser Sintering (SLS), which uses a laser beam to selectively sinter powder materials (such as nylon and ceramic powders); Selective Laser Melting (SLM) and Electron Beam Melting (EBM), which use high-energy beams to melt metal powders to directly manufacture high-performance metal components; and other processes such as 3D Printing Bonding (3DP), Thin Material Overlay (LOM), and Directional Energy Deposition (DED). Different processes have their own characteristics in terms of forming accuracy, forming efficiency, types of available materials, and component mechanical properties, and can be adapted to different application requirements.

[0003] Existing 3D printing equipment uses a chamber-wide heating mode, requiring the heating device to simultaneously heat all the air, inner walls, and frame structure within the entire enclosed chamber. This results in a large overall heat capacity, necessitating a lengthy preheating time to reach the required process temperature from room temperature. Furthermore, the chamber shell, assembly gaps, and opening / closing door areas continuously generate heat radiation and conduction, with some heat constantly dissipating to the external environment. This heat loss is not involved in the part forming and heat treatment process, leading to wasted thermal energy. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a high-temperature hot chamber type large-scale 3D printing device.

[0005] The present invention provides a high-temperature hot chamber type large-scale 3D printing device, including a chamber, an internal frame of which serves as the load-bearing component, a side plate connected to the side of the frame, and a heating plate embedded in the side plate for heating the printing area inside the chamber.

[0006] Furthermore, a lifting platform is slidably fitted on the frame, and the lifting platform is driven by a drive mechanism; the drive mechanism includes a Z-axis motor, the output end of the Z-axis motor is connected to a Z-axis lead screw, the Z-axis lead screw is threaded with a Z-axis nut, and the Z-axis nut is connected to the lifting platform.

[0007] Furthermore, the lifting platform is also equipped with an X-axis motor, the output end of which is connected to an X-axis lead screw, and the X-axis lead screw is threaded with an X-axis nut. A slide rail is connected to the X-axis nut, a Y-axis motor is connected to the slide rail, a Y-axis lead screw is connected to the output end of the Y-axis motor, a Y-axis nut is threaded onto the Y-axis lead screw, and a print head is connected to the Y-axis nut.

[0008] Furthermore, a sprocket seat is connected to the frame, a sprocket is provided inside the sprocket seat, a chain is engaged on the sprocket, one end of the chain is connected to the lifting platform, and the other end is connected to a counterweight, the counterweight being used to counteract the weight of the lifting platform.

[0009] Furthermore, the frame is also provided with lifting guide columns and counterweight guide columns. The lifting guide columns pass through the lifting platform and are used to provide rigid linear constraints for the lifting platform. The counterweight guide columns pass through the counterweight block and are used to provide rigid linear constraints for the counterweight block.

[0010] Furthermore, an X-axis accordion cover is connected between the slide rail base and the frame, a Y-axis accordion cover is connected between the print head and the slide rail base, and a Z-axis accordion cover is connected between the lifting platform and the frame. The accordion covers are used to synchronously extend and retract with the dynamic displacement of the print head, the slide rail base, and the lifting platform to maintain the airtightness of the printing area.

[0011] Furthermore, the print head includes a feeding seat, which has two feeding gears internally fitted. Each feeding gear is provided with a recess and a transmission part. The two feeding gears are driven by the transmission part and pass through the recess to form a feeding channel.

[0012] Furthermore, it also includes an electrical control cabinet, which stores a control program used to implement a printing temperature control method.

[0013] Furthermore, the printing temperature control method includes the following steps: S1: Obtain the current printing data, identify the printing hot zone of the current printing deposition operation based on the current printing data, and determine the release of the printing hot zone; S2: Heat the printable hot zone to the annealing temperature and maintain the annealing temperature; S3: When the annealing temperature is maintained for a preset duration, the temperature of the released printing hot zone is reduced to the cooling temperature. S4: Based on the actual temperature of the printing hot zone, calculate the power regulation protection amount of the released printing hot zone and apply a dynamic power upper limit constraint; S5: Based on the dynamic power upper limit constraint, compensate the released printing hot zone until all printing deposition operations are completed.

[0014] Furthermore, the specific steps for calculating the power regulation protection amount of the released printing hot zone and applying a dynamic power upper limit constraint are as follows: Based on the actual temperature of the printing hot zone, a continuous protection coefficient with a value range of 0 to 1 is calculated and used as the protection amount for hot zone power adjustment; Based on the protection amount of the hot zone power adjustment, a dynamic power upper limit constraint is applied to the closed-loop temperature control output of the released printing hot zone. The final actual heating power of the released printing hot zone is the smaller value between the PID temperature control output value and the dynamic power upper limit value.

[0015] In summary, the present invention has at least the following beneficial effects: 1. This invention integrates heating elements directly into the side wall of the chamber by embedding heating plates in the side panels of the frame, thereby providing directional heating to the printing and forming area. This replaces the traditional overall chamber heating mode, avoiding simultaneous heating of all air, the inner wall of the chamber, and the frame structure within the entire enclosed chamber. This effectively reduces the overall heat capacity of the system and significantly shortens the preheating time from room temperature to the process temperature. At the same time, the heating plates are arranged close to the forming area, reducing the ineffective heat loss to non-forming areas, improving the thermal energy utilization rate, and avoiding the defects of traditional heating elements such as delayed heating, large local temperature differences, and high energy consumption.

[0016] 2. This invention, by setting accordion covers on the X, Y, and Z axes and brushes on the sides of the lifting platform, forms a fully sealed protective structure that expands and contracts synchronously with the dynamic displacement of the print head, slide rail, and lifting platform. This maintains the airtightness and integrity of the printing cavity, effectively preventing external ambient temperature airflow and dust impurities from intruding into the forming area. It significantly reduces temperature fluctuations and local temperature differences in the forming space, lowers the surface temperature difference of the printed workpiece, and suppresses forming defects such as warping, interlayer cracking, and shrinkage deformation caused by uneven temperature field. At the same time, the brushes flexibly fill the gap between the lifting platform and the chamber, blocking heat leakage from the cavity through the gaps. Without rigid friction interference, it can adapt to the vertical displacement movement of the lifting platform, balancing sealing and movement flexibility.

[0017] 3. This invention, through a printing temperature control method, identifies and releases hot zones based on current printing data. It independently executes differentiated temperature trajectories for released hot zones, including heating and annealing, heat preservation, and controlled cooling. This allows printing and in-situ annealing to proceed in parallel. Heat treatment can begin immediately after printing, eliminating the need to remove the part from the chamber and transfer it to an external annealing furnace, significantly reducing the overall forming and heat treatment cycle. Simultaneously, based on the cumulative effective annealing time at the measured temperature of the hot zones, it can adaptively handle complex conditions such as power limitations and thermal coupling interference between hot zones. Furthermore, a dynamic power limit constraint is applied to the closed-loop temperature control output of released hot zones through a neighbor zone protection coefficient, preventing heat radiation and conduction from the high-temperature annealing zone from interfering with the hot zones currently being printed. This eliminates part forming defects caused by excessive temperature fields within the chamber, achieving precise and energy-efficient zoned heat treatment closed-loop control without altering the inherent annealing temperature process of the wire. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is an external structural diagram of the present invention; Figure 2 This is a diagram of the internal structure of the present invention; Figure 3 This is an external structural diagram of the right side plate of the present invention; Figure 4 This is a diagram of the driving structure of the slide rail base of the present invention; Figure 5 This is a structural diagram of the slide rail base of the present invention; Figure 6 This is a structural diagram of the printhead of the present invention; Figure 7 This is an internal structural diagram of the feeding seat of the present invention; Figure 8 This is the annealing temperature curve of the present invention.

[0020] Explanation of reference numerals in the attached diagram: 1. Container compartment; 2. Electrical control cabinet; 3. Casters; 4. Door; 5. Lifting platform; 6. Base plate; 7. Side plate; 8. Top plate; 9. Motor frame; 10. Z-axis servo motor; 11. Z-axis ball screw; 12. First chain column; 13. Chain; 14. Sprocket seat; 15. Sprocket; 16. Counterweight; 17. Second chain column; 18. Counterweight guide column; 19. Lifting guide column; 20. X-axis servo motor; 21. X-axis ball screw; 22. Slide rail 23. Y-axis servo motor; 24. Y-axis ball screw; 25. Heating plate; 26. Print head; 27. Feed guide tube; 28. Feeding gear; 29. ​​Feeding servo motor; 30. Heating box; 31. Feeding tube; 32. X-axis bellows cover; 33. Y-axis bellows cover; 34. Z-axis bellows cover; 35. Frame; 36. Connecting rod; 37. Z-axis nut; 38. Y-axis nut; 39. X-axis nut; 40. Feeding seat; 41. Recessed part; 42. Transmission part; 43. Brush. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] The following is in conjunction with the appendix Figures 1 to 8 The present invention will be described in further detail below.

[0023] like Figure 1 and Figure 2 As shown, a high-temperature hot chamber type large-scale 3D printing device includes a chamber 1, with an electrical control cabinet 2 hinged to one side of the chamber 1. The chamber 1 is rectangular, and a rectangular frame 35, adapted to the shape of the chamber 1, is bolted to its interior. The rectangular frame 35 serves as the core load-bearing skeleton of the chamber 1, capable of supporting and fixing various transmission, heating, movement, and printing execution components of the equipment from all directions, effectively improving the overall structural rigidity. A chamber door 4 is provided on the front of the frame 35. The chamber door 4 is a double door, with a short opening and closing stroke and convenient operation, suitable for loading and unloading large-sized printed workpieces. Universal wheels 3 are connected to the bottom surfaces of both the chamber 1 and the electrical control cabinet 2. Utilizing the flexible steering and rolling support characteristics of the universal wheels 3, the entire 3D printing device can be freely moved, greatly improving the handling flexibility of the equipment.

[0024] like Figure 3As shown, the bottom surface of frame 35 is bolted to a base plate 6, and the two sides and back of frame 35 are bolted to side plates 7. The top surface of frame 35 is bolted to a top plate 8 via multiple sets of evenly arranged connecting rods 36. A storage space is formed between frame 35 and top plate 8, which can be used to integrate other structural elements on the top surface of frame 35, achieving a compact layout of the equipment structure and reducing the overall space occupied by the machine. The inner walls of base plate 6, side plates 7, and top plate 8 are all lined with insulation material, which can effectively block the heat transfer from inside the compartment 1 to the outside, maintaining a constant temperature inside the compartment. Figure 2 As shown, heating plates 25 are embedded in the side plates 7 on both sides of the frame 35 in an array. The heating plates 25 are graphene heating plates. Relying on the ultra-high electrothermal conversion efficiency, ultra-fast thermal response rate and uniform surface heating characteristics of graphene material, rapid heating and uniform temperature control of the chamber can be achieved, which can greatly shorten the printing preheating waiting time and avoid the defects of traditional heating elements such as lag in heating, large local temperature difference and high energy consumption.

[0025] like Figure 3 As shown, a lifting platform 5 is slidably fitted onto the four columns of the frame 35. A drive mechanism is symmetrically arranged on both sides of the lifting platform 5, including a Z-axis servo motor 10. The Z-axis servo motor 10 is mounted on the top surface of the frame 35 via a motor frame 9. The output end of the Z-axis servo motor 10 is connected to a Z-axis ball screw 11, leveraging the high precision, low friction, and reversible transmission characteristics of the ball screw to achieve efficient conversion of rotary motion into linear motion. Z-axis nuts 37 are threaded onto the Z-axis ball screw 11, and all four Z-axis nuts 37 are bolted to the top surface of the lifting platform 5, driving the lifting platform 5 to move. This invention employs a synchronous linkage control scheme with four sets of Z-axis servo motors 10, driving the four Z-axis ball screws 11 to rotate synchronously, thereby driving the four Z-axis nuts 37 to move vertically synchronously, achieving stable and high-precision vertical lifting and feeding of the lifting platform 5, effectively meeting the precise displacement requirements of Z-axis layered stacking in 3D printing processes.

[0026] like Figure 3As shown, four sprocket seats 14 are bolted to the top surface of the frame 35. Two sprocket seats 14 are symmetrically arranged on either side of a motor frame 9, forming a symmetrical transmission layout. Each sprocket seat 14 is equipped with a sprocket 15, on which a chain 13 meshes. One end of the chain 13 passes through the frame 35 and is fixedly connected to the lifting platform 5 via a first chain post 12. The other end passes through the frame 35 and is fixedly connected to a counterweight 16 via a second chain post 17. The counterweight 16 is suspended in the middle of the frame 35. This chain counterweight balancing mechanism can accurately offset the self-weight of the lifting platform 5 and the gravitational load of the supporting accessories, significantly reducing the load torque and drive load of the Z-axis servo motor, reducing the stress and wear on transmission components such as the lead screw and guide rail, while suppressing inertial impact and slippage during the lifting process of the lifting platform, improving the smoothness of Z-axis motion start-stop and positioning accuracy, and extending the service life of the equipment's transmission components.

[0027] like Figure 3 As shown, two lifting guide columns 19 and two counterweight guide columns 18 are symmetrically vertically arranged between the top and bottom of the frame 35. The two lifting guide columns 19 pass through the lifting platform 5, providing rigid linear constraint on the vertical movement of the lifting platform 5 and preventing horizontal swaying and radial offset. The two counterweight guide columns 18 pass through the counterweight block 16, limiting the trajectory deviation of the vertical reciprocating motion of the counterweight block 16 and preventing the counterweight block from swinging or jamming. The symmetrical layout of the double sets of guide columns can achieve precise bidirectional movement limitation, greatly improving the smoothness and stability of the operation of the lifting platform 5 and the counterweight block 16, and ensuring the consistency of long-term reciprocating motion.

[0028] like Figure 4 As shown, two X-axis servo motors 20 are bolted to both ends of the lifting platform 5. The output ends of the X-axis servo motors 20 are connected to X-axis ball screws 21, and X-axis nuts 39 are threaded onto the ball screws 21. A slide rail seat 22 is bolted between the two X-axis nuts 39. This dual-motor, dual-screw synchronous drive structure ensures the parallelism and uniformity of the horizontal displacement of the slide rail seat 22. Figure 5 As shown, one end of the slide rail 22 is fixedly connected to a Y-axis servo motor 23 by bolts. The output end of the Y-axis servo motor 23 is connected to a Y-axis ball screw 24. A Y-axis nut 38 is threaded onto the Y-axis ball screw 24. Two print heads 26 are fixedly connected to the bottom surface of the Y-axis nut 38 by bolts. Through the linkage closed-loop control of the X-axis servo motor 20 and the Y-axis servo motor 23, the print heads 26 can be driven to achieve precise horizontal movement and trajectory motion in the X and Y axes of the horizontal plane, matching the 2D scanning and forming requirements of 3D printing. The dual print head structure can realize dual-color, dual-material printing operations, effectively improving printing efficiency and equipment versatility.

[0029] Before the 3D printing operation begins, the double-opening chamber door 4 is closed, creating a sealed cavity inside the chamber 1 to block heat exchange through air convection. Then, the heating plate 25 provides uniform heating throughout the chamber, creating a stable high-temperature environment. This sealed, high-temperature environment effectively slows down the cooling rate of the melted thermoplastic filament, reduces the temperature difference between the inside and outside of the printed workpiece, minimizes the shrinkage differences between the surface and inner layers, lowers internal stress during molding, and suppresses molding defects such as warping, interlayer cracking, and shrinkage deformation.

[0030] During the 3D printing process, solid 3D filament is fed from the print head 26 to the forming surface of the base plate 6. Driven by the high-precision trajectory of the X-axis and Y-axis servo motors, the print head 26 completes a single-layer planar printing operation according to the preset model path. After the single-layer printing process is completed, the Z-axis servo system drives the lifting platform 5 to move up precisely by one layer thickness, switching to the next forming surface. The planar printing process is repeated in a cycle. Through the method of layer stacking and solidification, the overall forming process of the three-dimensional solid model is finally completed.

[0031] like Figure 6 and Figure 7 As shown, each printhead 26 is connected to a guide tube 27, and a feeding seat 40 is bolted to the feeding outlet of the guide tube 27. Two symmetrically arranged feeding gears 28 are rotatably fitted inside the feeding seat 40. The surfaces of the feeding gears 28 are provided with recesses 41 and transmission parts 42. The recesses 41 of the two sets of feeding gears together form a filament conveying path. The outlet port of the guide tube 27 is positioned directly over this path to ensure accurate 3D filament feeding. The two feeding gears 28 mesh through the transmission part 42, and one of the feeding gears 28 is independently driven by an external feeding servo motor 29. The feeding tube 31 is connected directly below the recesses 41, and the bottom end of the feeding tube 31 is connected to the heating box 30, forming a complete filament conveying, extrusion, and melting molding path.

[0032] During the printing process, the 3D filament is precisely guided through the guide tube 27 into the concave passage 41 of the two sets of feeding gears 28. The feeding servo motor 29 precisely drives the two sets of feeding gears 28 to mesh and rotate synchronously. The concave structure of the gears forms a flexible clamp, uniform extrusion, and quantitative feeding of the filament, realizing the control of the feeding speed and amount of consumables and avoiding problems such as feeding jams, material breakage, overflow, and uneven feeding. After being extruded and pushed, the 3D filament enters the heating box 30. Through the heating of the heating box 30, the solid thermoplastic filament is melted and transformed into a high-viscosity viscous fluid. The molten consumables have excellent fluidity and adhesion, and can be uniformly extruded from the bottom outlet of the heating box 30, accurately stacked and formed, ensuring the interlayer fusion effect and the regularity of the formed workpiece.

[0033] like Figure 2 and Figure 5As shown, X-axis bellows covers 32 are connected between the two sides of the slide rail 22 and the frame 35, Y-axis bellows covers 33 are connected between the two ends of the print head 26 and the slide rail 22, and Z-axis bellows covers 34 are connected between the two sides of the lifting platform 5 and the base plate 6. Through the full-area bellows sealing and protection structure along the X, Y, and Z axes, it can synchronously extend and retract with the dynamic displacement of the print head 26, slide rail 22, and lifting platform 5, always maintaining the airtightness and integrity of the printing cavity, effectively isolating external ambient temperature airflow and dust impurities from intruding into the printing area, significantly reducing temperature fluctuations and local temperature differences in the printing space, and lowering the surface temperature difference of the printed workpiece. Figure 3 As shown, a row of brushes 43 is provided on each of the four sides of the lifting platform 5. The brushes 43 flexibly fill the gap area between the lifting platform 5 and the chamber 1. By utilizing the gap-sealing and turbulence-blocking characteristics of the flexible brushes, the convection exchange of hot and cold air inside and outside the chamber 1 is effectively weakened, and the heat inside the cavity is blocked from leaking out through the gaps. This continuously maintains a high-temperature constant temperature environment inside the molding cavity, improving temperature control accuracy and heat energy utilization. At the same time, the flexible structure of the brushes has no rigid friction interference, which can adapt to the vertical displacement movement of the lifting platform 5 without affecting the normal transmission operation of the equipment, thus balancing sealing and movement flexibility.

[0034] The electrical control cabinet 2 also stores a printing temperature control method, which is used to achieve parallel printing and annealing operations. For example... Figure 8 As shown, this embodiment uses Victrex AM™200 polyaryletherketone thermoplastic material as the printing filament. This type of material, when molded at temperatures below 150°C, can produce predominantly amorphous printed parts. The recommended annealing temperature window for this material is 170°C-180°C, with a preferred target annealing temperature of 175°C; the effective annealing holding time is 2-4 hours, preferably 3 hours; the heating and cooling rates are controlled at 1-3°C / min, preferably 2°C / min; and the cooling endpoint is set at 130°C to facilitate a smooth transition with the device's natural cooling process.

[0035] The printing temperature control method includes the following steps: Step 1: Obtain input data.

[0036] The current print data is obtained via G-code; the current print data includes the wire deposition path, wire deposition progress, and the measured temperature of each print hot zone.

[0037] Step 2: Hot Zone Identification and Release Determination.

[0038] Based on the acquired current printing data, the hot zone of the current printing deposition operation is identified, and a release determination is made for the hot zone. The determination condition is a dual-condition verification: first, there is no subsequent deposition path within the hot zone; second, the current deposition position crosses the boundary of the hot zone and a calibrated safety distance is reserved; and the device safety status verification is passed at the same time, only then can the hot zone be determined as a released hot zone.

[0039] The logic for releasing the printing hot zone is expressed as follows:

[0040] In the formula: Indicates the release status of the i-th printed hot zone; The path analysis indicates that no further deposition occurred within the printed hot zone; Indicates the current Z-axis height being printed; This indicates the height of the upper boundary of the i-th printed hot zone; This indicates the calibrated safe distance; This indicates the device's safety verification status.

[0041] This dual-verification release logic prevents the print head 26 from falling back into the already heated and annealed printing hot zone, thus preventing the high-temperature annealing environment from damaging the amorphous forming conditions of the workpiece to be printed and improving the control reliability in the workpiece printing scenario.

[0042] Step 3: Assign differentiated temperature operating trajectories.

[0043] Maintain the temperature of the printing hot zone currently being printed at 135℃, below the filament forming temperature. For printing hot zones that have completed printing and meet the release conditions, first raise the temperature to 175℃, then maintain the effective annealing time for 3 hours, and finally lower the temperature to 130℃. Multiple released printing hot zones can be in different heat treatment stages; each printing hot zone records its own effective annealing time independently, and the timing of each printing hot zone does not interfere with each other.

[0044] This step allows printing and in-situ annealing to be carried out in parallel. The area that has been printed can be heat treated immediately without removing the part from the cavity and transferring it to an external annealing furnace.

[0045] Step 4: Accumulate the effective heat treatment amount.

[0046] The effective annealing time for a printed hot zone is only accumulated when the released hot zone is in the annealing hold state, the measured temperature reaches the annealing temperature window, and the sensor is working properly. If the measured temperature exceeds the annealing temperature window or the sensor malfunctions, the accumulation of effective annealing time is paused, and the heating phase is not included in the annealing time.

[0047] Formula for iterative calculation of effective annealing time:

[0048] Formula for calculating annealing completion:

[0049] In the formula, This indicates the cumulative effective annealing time for the i-th printed hot zone; Indicates the control cycle; Indicates the operating status of the printing hot zone; This indicates the real-time measured temperature of the printing hot zone; These represent the lower and upper threshold values ​​of the effective annealing temperature window, respectively. This indicates the preset effective annealing time; This indicates the annealing completion rate of the corresponding printed hot zone. This cumulative logic is based on the actual measured temperature of the device rather than a set temperature timing, and can adaptively handle complex operating conditions such as power constraints, thermal coupling interference in the hot zone, and short-term temperature deviation windows, ensuring the authenticity and accuracy of the effective annealing time statistics.

[0050] Step 5: Neighbor Cell Protection - Dynamic Power Limit Limit.

[0051] Based on the measured temperature of the current printing hot zone, a continuous protection coefficient ranging from 0 to 1 is calculated and used as the protection amount for power adjustment of the printing hot zone. The closer the real-time temperature of the printing hot zone is to the upper limit of the allowable forming temperature, the lower the protection coefficient value, and the stronger the power restriction on the annealing printing hot zone.

[0052] By applying a dynamic power upper limit constraint to the closed-loop temperature control output of the released printing hot zone through this protection, the final actual heating power command of the printing hot zone is taken as the smaller value between the conventional PID temperature control output value and the dynamic power upper limit value, so as to avoid the heat radiation and heat conduction of the high-temperature annealing area from interfering with the printing hot zone that is being printed, and to eliminate the part forming defects caused by the temperature field exceeding the limit in the chamber 1.

[0053] The formulas for calculating the adjacent zone protection factor, the upper limit of the hot zone power, and the final output power are as follows:

[0054]

[0055]

[0056] In the formula: Indicates the neighbor cell protection coefficient; Indicates the upper limit threshold for the temperature protection of the printing hot zone; This indicates the measured temperature of the printed hot zone; Indicates the preset upper limit of temperature protection; Indicates the rated heating power of the printing hot zone; Indicates the correction factor for the operating status of the printing hot zone; This represents the temperature control error correction coefficient; Indicates the maximum allowable power for the printing hot zone; This represents the output power value of the temperature control PID algorithm; This indicates the final heating power command executed in the printed hot zone. This protection mechanism only limits the heating power output and does not change the inherent annealing temperature process of the wire. When the power limitation causes the annealing heating and holding process to be prolonged, the effective cumulative annealing time can be automatically recorded to ensure accurate subsequent temperature compensation.

[0057] Step Six: Stage Switching and Heat Treatment Supplementation.

[0058] When the effective annealing time of a certain released printing hot zone reaches the preset target time, the heat treatment of that printing hot zone is determined to be up to standard. The system automatically controls the hot zone to enter a controlled cooling state and performs cooling at a set cooling rate of 2℃ / min until the temperature drops to the cooling endpoint of 130℃. After the entire printing job is completed, the system checks the annealing completion of all physical hot zones. Only for hot zones where the effective heat treatment amount has not reached the target value and there is a heat treatment gap, the remaining heat treatment time is supplemented separately. The remaining hot zones that have met the heat treatment standard do not repeat the complete annealing cycle, realizing precise and energy-saving zoned heat treatment closed-loop control.

[0059] Each independent physical hot zone is configured with a separate status management mechanism to independently maintain the operating status of the printing hot zone. Target set temperature Real-time measured temperature Effective annealing cumulative time Dynamically permissible power limit The five core parameters and the independent, non-interfering operating states of each printing hot zone are as follows: The specific state switching conditions, control objectives, and exit conditions are as follows:

[0060] Example of zoned working conditions: The space of chamber 1 is evenly divided into four independently temperature-controlled printing hot zones: C1, C2, C3, and C4, along the Z-axis printing height direction. Each hot zone has independent temperature control, independent state switching, and independent cumulative annealing time. In actual printing operations, when the deposition operation of printhead 26 reaches the C3 printing hot zone, the working status of each hot zone is as follows: the C4 printing hot zone is in STANDBY standby mode, maintaining heating off or low-power preheating mode, waiting for the printing operation to extend upwards; the C3 printing hot zone is the current core printing hot zone, continuously maintaining a low-temperature forming temperature of 135℃ to complete the layer-by-layer wire deposition operation; the C2 hot zone has completely completed the deposition path of all internal parts and meets the safety release spacing requirements, entering the HOLD annealing hold state, stably maintaining the optimal annealing temperature of 175℃, and performing in-situ heat treatment on the internally printed parts; the C1 hot zone has completed the entire effective annealing holding time, entering the COOL controlled cooling state, gradually cooling down to 130℃ and holding at low power.

[0061] Under this operating condition, the device achieves a parallel and collaborative operation mode of upper printing, middle annealing, and lower cooling, completing in-situ annealing of zones without interrupting the printing process, and significantly reducing the overall forming and heat treatment cycle.

[0062] In the description of this invention, it should be understood that the terms "bottom," "top," "lower," "side," "top," "above," "lower," "outer," "one end," "the other end," and "both sides," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. In the description of this invention, unless otherwise specified and limited, it should be noted that the term "connection" should be interpreted broadly. For example, it can refer to a mechanical connection or an electrical connection, or the internal connection of two elements. It can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0063] The above are merely preferred embodiments of the invention and are not intended to limit the invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the invention should be included within the protection scope of the invention.

Claims

1. A high-temperature hot chamber type large-scale 3D printing device, comprising a chamber, wherein a frame is disposed inside the chamber, and the frame serves as a load-bearing component of the chamber; characterized in that, The frame is connected to a side plate, and a heating plate is embedded in the side plate. The heating plate is used to heat the printing and forming area inside the container.

2. The high-temperature hot chamber type large-scale 3D printing device according to claim 1, characterized in that, A lifting platform is slidably fitted onto the frame, and the lifting platform is driven by a drive mechanism. The drive mechanism includes a Z-axis motor, the output end of which is connected to a Z-axis lead screw. The Z-axis lead screw is threaded with a Z-axis nut, which is connected to the lifting platform.

3. The high-temperature hot chamber type large-scale 3D printing device according to claim 2, characterized in that, The lifting platform is also equipped with an X-axis motor, the output end of which is connected to an X-axis lead screw, and the X-axis lead screw is threaded with an X-axis nut. A slide rail is connected to the X-axis nut, a Y-axis motor is connected to the slide rail, a Y-axis lead screw is connected to the output end of the Y-axis motor, a Y-axis nut is threaded onto the Y-axis lead screw, and a print head is connected to the Y-axis nut.

4. The high-temperature hot chamber type large-scale 3D printing device according to claim 2, characterized in that, A sprocket seat is connected to the frame, a sprocket is installed inside the sprocket seat, a chain is engaged on the sprocket, one end of the chain is connected to the lifting platform, and the other end is connected to a counterweight, which is used to counteract the weight of the lifting platform.

5. The high-temperature hot chamber type large-scale 3D printing device according to claim 4, characterized in that, The frame is also provided with lifting guide columns and counterweight guide columns. The lifting guide columns pass through the lifting platform and are used to provide rigid linear constraints for the lifting platform. The counterweight guide columns pass through the counterweight block and are used to provide rigid linear constraints for the counterweight block.

6. The high-temperature hot chamber type large-scale 3D printing device according to claim 3, characterized in that, An X-axis accordion cover is connected between the slide rail base and the frame, a Y-axis accordion cover is connected between the print head and the slide rail base, and a Z-axis accordion cover is connected between the lifting platform and the frame. The accordion covers are used to synchronously extend and retract with the dynamic displacement of the print head, the slide rail base, and the lifting platform to maintain the airtightness of the printing area.

7. The high-temperature hot chamber type large-scale 3D printing device according to claim 3, characterized in that, The print head includes a feeding seat, which has two feeding gears inside. Each feeding gear has a recess and a transmission part. The two feeding gears are driven by the transmission part and pass through the recess to form a feeding channel.

8. The high-temperature hot chamber type large-scale 3D printing device according to claim 3, characterized in that, It also includes an electrical control cabinet, which stores a control program used to implement a printing temperature control method.

9. The high-temperature hot chamber type large-scale 3D printing device according to claim 8, characterized in that, The printing temperature control method includes the following steps: S1: Obtain the current printing data, identify the printing hot zone of the current printing deposition operation based on the current printing data, and determine the release of the printing hot zone; S2: Heat the printable hot zone to the annealing temperature and maintain the annealing temperature; S3: When the annealing temperature is maintained for a preset duration, the temperature of the released printing hot zone is reduced to the cooling temperature. S4: Based on the actual temperature of the printing hot zone, calculate the power regulation protection amount of the released printing hot zone and apply a dynamic power upper limit constraint; S5: Based on the dynamic power upper limit constraint, compensate the released printing hot zone until all printing deposition operations are completed.

10. The high-temperature hot chamber type large-scale 3D printing device according to claim 9, characterized in that, The specific steps for calculating the power regulation protection amount of the released printing hot zone based on the actual temperature of the printing hot zone, and applying a dynamic power upper limit constraint, are as follows: Based on the actual temperature of the printing hot zone, a continuous protection coefficient with a value range of 0 to 1 is calculated and used as the protection amount for hot zone power adjustment; Based on the protection amount of the hot zone power adjustment, a dynamic power upper limit constraint is applied to the closed-loop temperature control output of the released printing hot zone. The final actual heating power of the released printing hot zone is the smaller value between the PID temperature control output value and the dynamic power upper limit value.

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