Energy-saving three-dimensional additive printing forming device with cavity width temperature control volume variable

Abstract

The application discloses a kind of cavity width energy-saving forming equipment of additive printing variable volume, belong to 3D printing technical field, including rack, cavity, three-axis sealed heat insulation mechanism, cold and hot temperature control system, extrusion mechanism and monitoring system.Printing cavity realizes volume self-adaptive adjustment by movable plate piece;Cold and hot temperature control system has compression temperature control and pure electric heating function, and mode interlock is provided;Hot bed is modular low-expansion high-temperature-resistant structure, three-axis is provided with sealed heat insulation structure, Y-axis tunnel air duct integrates monitoring device, can collect topographic thermal field data, identify printing defects, air duct is low-temperature component heat dissipation and does not interfere with injection head constant temperature;Extrusion end is provided with rotary multi-channel injection head, supports multi-material on-line material change.The application solves the problems of large piece printing warping and cracking, high energy consumption and difficult real-time monitoring of defects, can be adapted to high and low temperature polymer forming, realizes energy-saving operation, improves the defects of traditional equipment cavity fixed, narrow temperature control range, sealing heat leakage and poor forming stability.

Description

Technical Field

[0001] This invention relates to the field of 3D printing equipment technology, specifically to an energy-saving stereolithography additive printing equipment with a variable volume and wide temperature control cavity. Background Technology

[0002] Large-scale polymer 3D printing is highly dependent on the temperature environment of the cavity, and existing commercial equipment has the following drawbacks: The printing cavity volume is fixed, which cannot match workpieces of different shapes and sizes; there is a large ineffective heating space and the overall energy consumption of the machine is relatively high. The temperature control range is narrow and cannot simultaneously cover two types of working conditions: low-temperature flexible material curing and high-temperature polymer melting molding. The sealing structure of the moving parts of the cavity is rudimentary, resulting in continuous heat loss during operation, poor temperature stability, and insufficient high-temperature flatness of the heated bed. Printing is completed solely by pre-set programs, and the finished workpieces are mostly inspected manually afterward, lacking real-time online monitoring capabilities. Single visual acquisition can only identify appearance defects and cannot detect hidden faults such as melting temperature and interlayer adhesion. Delayed fault detection can easily lead to batch scrapping of workpieces, and the equipment has a low level of intelligence.

[0003] The present invention aims to overcome all the defects of the prior art. Summary of the Invention

[0004] The purpose of this invention is to provide a three-dimensional additive printing energy-saving molding equipment with a wide-range temperature control and variable volume cavity, which can realize stable molding of large polymer parts over a wide range, adaptive adjustment of cavity volume, dynamic sealing and heat preservation, real-time online monitoring of molding defects, and rapid switching extrusion of multiple materials.

[0005] The overall structure and working principle of this invention are described in detail below: Destructible variable volume cavity

[0006] The breakable cavity is fixedly installed inside the equipment frame. The cavity is vertically fitted with a movable top plate or a movable bottom plate, which can slide independently in the vertical direction. The distance between the top plate and the bottom plate can be adjusted according to the height of the workpiece to be printed, reducing the effective volume inside the cavity as needed and reducing the ineffective temperature control space. Intracavitary air distribution component

[0007] The cavity air distribution assembly includes two independent air paths: an internal air distribution system for the working cavity and an internal tunnel pipe cooling system.

[0008] The cavity is equipped with a circulating air system, which uses a fan to agitate the airflow inside the cavity to homogenize the temperature throughout the cavity, keeping the temperature difference between the workpiece and the cavity environment within ±2℃, thus eliminating problems such as workpiece warping and poor melting state of consumables caused by local temperature differences.

[0009] The tunnel tube cooling system uses positive pressure cooling air to keep the temperature of high-temperature-sensitive components inside the tunnel tube constant, ensuring that precision parts do not deform or lose precision under high-temperature conditions. Standard and general-purpose parts can work stably in the high-temperature cavity, reducing the cost of purchasing and using equipment parts. Wide temperature control system with interlocking thermal properties

[0010] The hot and cold temperature control system is connected to the printing cavity piping and electrical system, and integrates independent compressor unit temperature control components and electric heating components. It is equipped with an electrical interlock mechanism, which allows only the compressor unit temperature control mode or pure electric heating mode to be operated at the same time.

[0011] The compressor unit's temperature control mode relies on compressor circulation to achieve cooling and constant temperature control in the low-temperature range of the cavity, which is suitable for molding low-temperature curing flexible polymer materials. When the required cavity temperature reaches or exceeds the set threshold, the compressor unit stops working and switches to pure electric heating mode. It supports independent start and stop of heating components in the cavity zones, and the cavity maintains a stable high temperature throughout. It is suitable for high-temperature polymer melting molding of nylon, glass fiber modified consumables, PEEK and other materials. Modular low-expansion heated bed base

[0012] The bottom of the printing cavity is equipped with a modular splicing low-expansion high-temperature resistant hot bed base plate, which is composed of multiple square rigid unit blocks tightly spliced ​​together; stress release gaps are reserved between adjacent unit blocks, and the unit blocks can release thermal stress by slight displacement within the gaps during the equipment's heating and cooling process, thus maintaining the hot bed plane accuracy over a long period of time; the unit blocks are made of a low expansion coefficient substrate, which has the characteristics of high temperature resistance, high rigidity, and high flatness under high temperature working conditions. Triaxial dynamic sealing insulation system

[0013] The Z-axis lifting mechanism is fitted with an interlocking tape sealing strip and a follow-up lip-type clamping plate sealing reinforcement mechanism at the connection position with the cavity worktable; interlocking sealing strips are fitted on both sides of the X-axis transmission mechanism and the front side of the Y-axis moving mechanism; the cavity gaps are continuously sealed throughout the three-axis reciprocating motion process, reducing heat leakage from the cavity to the outside and reducing the energy consumption of the temperature control system for continuous heating / cooling. Working condition fusion data acquisition and monitoring device

[0014] The monitoring system is integrated and installed inside the tunnel duct and moves synchronously back and forth with the Y-axis. The hardware includes two independent detection units: a high-definition visible light morphology camera and an infrared thermal imaging temperature measurement probe, which can simultaneously collect the appearance morphology data of the formed area and the temperature data of the area's thermal field. The main control unit matches the two types of collected data with the real-time coordinates of the nozzle, automatically identifying molding defects such as layer thickness deviation, broken wires, workpiece warping, localized overheating, and interlayer bonding failure. Once a fault is detected, an audible and visual alarm is immediately triggered. The system has reserved expansion interfaces, allowing for the addition of extra data acquisition components such as deformation detection and mechanical detection to expand the monitoring dimensions as needed. Rotary multi-color multi-channel injection head

[0015] The injection head is fixedly installed at the end of the Y-axis extrusion mechanism. The upper part of the main body is equipped with a multi-channel feeding structure that can rotate circumferentially, with at least two sets of independent feeding channels. Different consumable feeding channels are switched by rotation. The mechanical origin positioning repeatability is ≤0.01mm. There is no need to perform origin offset calibration when printing is paused. Consumables and filaments can be replaced directly on site, and the extrusion head can be replaced as a whole, shortening the production changeover waiting time. Beneficial effects Energy saving and consumption reduction

[0016] The cavity volume adaptively adjusts with the workpiece size, reducing ineffective heating / cooling space as needed, and combined with triaxial dynamic sealing to reduce heat loss, significantly reducing the overall temperature control energy consumption of the machine; The cavity air distribution system evens out the temperature across the entire area, avoiding ineffective energy consumption and waste caused by local overheating. Molding accuracy and stability

[0017] Modular heated beds release thermal stress by relying on the gaps between unit blocks, maintaining high-temperature planar accuracy over a long period of time and suppressing warping and interlayer cracking defects in large workpieces. The wide-temperature-range interlocking temperature control system precisely matches the molding process requirements of different polymer materials, ensuring the stability of the molten and solidified state of the consumables and improving the strength of the integrated structure of the workpiece. Intelligent monitoring and maintenance category

[0018] Real-time online monitoring of both morphology and thermal field can identify hidden forming defects in advance, avoid batch scrapping of workpieces, and reduce production losses. The monitoring system supports dimensional expansion and can be adapted to the full-process tracking and detection needs of different high-precision workpieces. Production efficiency

[0019] The rotary multi-color multi-channel injection head supports on-site calibration-free material and head changes, shortening the time required for changing the form of multiple materials and batches of workpieces. The tunnel ventilation duct uses standard components for independent heat dissipation, eliminating the need for customized high-temperature resistant special parts, thus reducing equipment manufacturing, maintenance, procurement, and usage costs. Example 1 (Standard Construction Conditions)

[0020] This energy-saving additive manufacturing equipment features a wide-range temperature-controlled, variable-volume 3D printing chamber. It consists of a frame, a breakable, variable-volume chamber, an X-axis drive mechanism, a Y-axis moving mechanism, a Z-axis lifting mechanism, a hot and cold temperature control system, a modular, modular heated bed base, a rotary multi-color, multi-channel injection head, and a fusion-based data acquisition and monitoring device. The printing chamber is fixed inside the frame, and the top and bottom plates allow for vertical sliding adjustment of the chamber volume. A circulating fan continuously agitates the airflow, maintaining the temperature difference between the workpiece and the environment within ±2℃.

[0021] The cold and hot temperature control system is electrically interlocked, and the compressor unit has zoned temperature control in temperature adjustment mode and pure heating mode; stress relief gaps are set between the heated bed unit blocks, and thermal stress is released by slight displacement during temperature rise and fall.

[0022] All X / Y / Z axes are equipped with corresponding staggered meshing, follow-up lip-type clamp seal structures; the monitoring system in the Y-axis air duct moves with the axis to collect morphology and thermal field data, and defects trigger audible and visual alarms.

[0023] The internal tunnel cooling system continuously provides cooling air to the tunnel, suppressing the temperature rise inside the tube and providing a stable working environment for equipment that is not resistant to high temperatures.

[0024] The rotary injection head has 3 sets of feeding channels, and the origin repeatability is ≤0.01mm. The material and head can be changed directly when printing is paused.

[0025] Equipment operation process: Adjust the cavity volume according to the workpiece size → Select the cooling / heating temperature control mode → The three-axis mechanism drives the injection head to print layer by layer → The monitoring system provides online quality control throughout the process, and energy-saving and stable molding is achieved by relying on the sealed and uniform temperature structure. Example 2 (Dedicated working condition for high-temperature melting polymer consumables)

[0026] When printing high-temperature molten polymer workpieces, the hot and cold temperature control system is switched to pure electric heating mode, and the cavity can be kept at a constant temperature as needed in the high-temperature range; at the same time, the modular splicing low-expansion high-temperature resistant hot bed base plate is preheated to the high temperature of the compatible consumables; during the printing process, the working condition fusion acquisition and monitoring device continuously collects two types of data: the thermal stress distribution at the edge of the workpiece and the interlayer fusion bonding state; the dynamic sealing and heat insulation structure matched with the X / Y / Z axis completely isolates the heat leakage inside the cavity, preventing the interlayer bonding failure of the workpiece due to the drop in cavity temperature; the main control system of the whole machine controls the rotary multi-color injection head to switch to the dedicated feeding channel adapted to the high-temperature consumables, and automatically completes the extrusion molding of the workpiece. Example 3 (Dedicated operating conditions for low-temperature flexible materials)

[0027] When printing low-temperature curing flexible polymer materials, the temperature control system switches to the compressor unit temperature adjustment mode, keeping the cavity at a low and constant temperature to ensure stable printing operations. Attached Figure Description

[0028] Figure 1Main view Figure 2 Side view Figure 3 Top view Figure 4 Top right corner axonometric drawing Figure 5 Rotary multi-color multi-channel injection head structure diagram Figure 6 Diagram of a breakable, variable-volume cavity structure 1. Rack 2. Z-axis lead screw fixing block 3. Z-axis lead screw 4. Interlocking meshing tape sealing strip winding mechanism 5. X-axis / lateral motion groove interlocking winding and sealing strip retraction mechanism 6. X-axis guide rail 7. Destructible, variable-volume, movable top plate 8. Destructible, variable-volume cavity front wall panel 9. Z-axis synchronous belt 10. Low-expansion heated bed base plate with built-in electric heating components. 11. Observation glass window of the working condition fusion acquisition and monitoring device located inside the Y tunnel pipe 12. Y-axis tunnel ventilation duct of the tunnel cooling system (This figure shows the tunnel duct inspection cover in the open state; the inspection cover is closed during normal operation). 13. Rotary multi-color multi-channel injection head 14. Cold air corrugated pipe 15. Consumables delivery pipe 16. Cooling air duct joint for Y-axis tunnel ventilation duct of tunnel cooling system 17. Y-axis belt 18. Y-axis motor 19. Consumables Dryer 20. Evaporative air cooler 21. Slider 22. Guide rail 23. Belt guide pulley 24. Working face support 25. Guide rail 26. Slider 27. Y-axis moving support inside the tunnel pipe 28. Y-axis motion groove interlocking winding sealing strip 29. High-temperature resistant tunnel ventilation wall 30. The side plate of the variable-volume cavity can be broken open, and it contains a layered, independently operable distributed electric heating assembly. 31. Cutting steel sheets 32. Connecting plate on tunnel ventilation duct 33. Tunnel duct ventilation outlet 34. X-axis / lateral motion groove interlocking winding sealing strip 35. Tunnel pipe bridge deck 36. Consumables 37. Feed follower meshing gear 38. Feed drive meshing gear 39. Swinging engagement locking mechanism 40. Rotary injection head positioning locking pin 41. Rotary injection head indexing gear disc 42. Heat sink for the feed pipe of the high-temperature rotary injection head 43. One of the components of the tunnel pipe Y-axis motion groove interlocking winding sealing strip assembly. 44. Part Two of the Tunnel Pipe Y-axis Motion Groove Interlocking Winding Strip Assembly 45. Rotary injection head support 46. ​​Consumables wiring (illustrated) 47. Replaceable injection nozzle 48. Feed motor 49. Feed hole 50. Misaligned feed conduit 51. Injection head indexing plate 52. Screw motor 53. Screw 54. Off-center feeding follower disc 55. Adaptive lip-type clamp seal reinforcement mechanism assembly 56. One of the components of the X-axis / lateral motion groove interlocking conveyor belt sealing strip assembly. 57. Part Two of the X-axis / lateral motion groove interlocking winding tape sealing strip assembly 58. Low-expansion hot-bed molded panel 59. Movable base plate 60. Shaped thermal insulation sheet 61. Anti-scratch film 62. Air distribution system within the working chamber.

Claims

1. A three-dimensional additive printing energy-saving molding equipment with a wide-range temperature control cavity and variable volume, characterized in that: It includes a frame, a closed cavity, an internal air distribution assembly, a wide-range hot and cold temperature control system, a low-expansion heated bed base plate, a multi-directional sealing and insulation assembly, an operating condition fusion acquisition and monitoring device, and a printing actuator. The enclosed cavity is assembled on the frame, and the cavity can extend and retract in multiple directions to adjust the internal forming volume; The cavity air distribution component is disposed inside the cavity to balance the temperature inside the cavity; The wide-range cold and hot temperature control system is connected to the cavity, enabling bidirectional independent temperature control for low-temperature constant temperature and high-temperature heating; The low-expansion hot bed base plate is fixedly installed at the bottom of the cavity to provide a flat forming working surface; The multi-directional sealing and heat insulation component is assembled at each expansion joint of the cavity, and can continuously seal the joint gap as the cavity slides, maintaining the cavity in a sealed state. The working condition fusion acquisition and monitoring device is used to collect workpiece forming condition data online. The printing actuator is located inside the cavity and is used to complete the stereo additive manufacturing process.

2. The energy-saving stereolithography equipment with variable volume and wide temperature control cavity as described in claim 1, characterized in that, The enclosed cavity is a breakable, variable-volume cavity, equipped with a vertically sliding top or bottom plate and a vertical lifting and sliding mechanism. The vertical lifting and sliding mechanism can drive the top or bottom plate of the cavity to rise and fall as a whole, thereby flexibly adjusting the internal space of the cavity. An anti-scratch film is provided on the inner side of the forming cavity. A sealing component that can slide relative to the wall is provided in the cavity. When the sealing component slides, it will cause friction and scratches on the inner wall. The anti-scratch film can resist the scratches caused by the sliding of the sealing component, realize the protection of the inner wall of the cavity, and at the same time allow heat radiation to penetrate. The heat generated by the cavity wall can be radiated to the forming workpiece and the cavity through the anti-scratch film.

3. The energy-saving stereolithography equipment with variable volume and wide temperature control cavity as described in claim 1, characterized in that, The cavity air distribution assembly includes two independent air paths: a working cavity air distribution system and a cavity tunnel pipe cold air system.

4. The energy-saving stereolithography equipment with variable volume and wide temperature control cavity as described in claim 1, characterized in that, The wide-range cold and hot temperature control component is equipped with an interlock structure; the interlock structure restricts the cold unit and the heating unit to operate only one at a time; the equipment is equipped with two independent temperature control units, namely the compressor air source temperature control unit and the electric heating unit, and the two types of temperature control units cannot be started simultaneously; The compressor air source temperature control unit has a large-span continuous temperature control capability. The low-temperature range is suitable for workpiece cooling and shaping, and the medium-temperature range is matched with the cavity for constant temperature control. It supports stepless constant temperature control within the range. The electric heating unit outputs a wide range of high temperatures, which is suitable for the molding temperature of consumables and can stably maintain any set heating temperature within the range. The wide-range cooling and heating temperature control component can be equipped with a compressor air temperature control unit to form a cooling-only model, or it can be equipped with an electric heating unit to form a heating-only model. The electric heating unit is arranged inside the cavity wall of the breakable cavity and is equipped with a distributed electric heating component that can be independently opened and closed in layers. The distributed electric heating component includes a heating winding laid on the low expansion heated bed base plate and a heating component set on the side of the movable top plate facing the cavity. When the top plate or bottom plate is adjusted to increase the cavity space, the layered heating component can gradually open and close the corresponding heating component in the cavity space according to the cavity space volume through mechanical switches and software control to achieve temperature control and energy saving.

5. The energy-saving stereolithography equipment with variable volume and wide temperature control cavity as described in claim 1, characterized in that, The low-expansion thermal bed base plate adopts a modular splicing structure, which is composed of multiple independent rigid unit blocks. Small gaps are reserved between adjacent unit blocks to release high-temperature thermal expansion stress.

6. The energy-saving stereolithography equipment with variable volume and wide temperature control cavity as described in claim 1, characterized in that, The multi-directional sealing and heat insulation components are arranged at the transverse and longitudinal sliding joints of the cavity and at the connection positions of the vertical telescopic cavity; each joint is equipped with staggered interlocking sealing strips and / or follow-up lip-type clamp sealing reinforcement mechanisms; the sealing strips can move synchronously with the moving components, continuously sealing the gaps in the movement and preventing the leakage of temperature-controlled airflow inside the cavity.

7. The energy-saving stereolithography equipment with variable volume and wide temperature control cavity as described in claim 3, characterized in that, The internal tunnel cooling system is arranged along the inside of the tunnel tube to form an independent heat dissipation channel for the components; the exhaust port of the tunnel tube is equipped with a temperature control element to detect the exhaust temperature; if the detected temperature is abnormal, the positive pressure cooling air of the tunnel tube is controlled to ensure that the components that are not resistant to high temperatures are kept at a constant temperature, and to avoid deformation and decrease in precision of precision components in high-temperature environments.

8. The energy-saving stereo additive printing molding equipment with variable volume and wide temperature control cavity as described in claim 3, characterized in that, The uniform airflow system inside the working chamber can reduce the temperature difference inside the chamber, reduce workpiece warping and deformation, and improve the interlayer fusion bonding strength of consumables.

9. The energy-saving stereolithography equipment with variable volume and wide temperature control cavity as described in claim 1, characterized in that, The working condition fusion acquisition and monitoring device is installed inside the air duct and moves synchronously with the tunnel air duct inside the cavity; the device compares the acquired morphological images, thermal field temperature data and the real-time movement coordinates of the nozzle one by one, automatically identifies forming defects and triggers audible and visual alarms; the monitoring system has reserved expansion space, which can add detection components to expand the monitoring dimensions according to the detection needs.

10. The energy-saving stereolithography equipment with variable volume and wide temperature control cavity as described in claim 1, characterized in that, The printing actuator includes a rotary multi-channel injection head; the injection head is equipped with a rotatable feeding structure, and the staggered feeding follower disk can prevent the feeding guide from getting tangled. The feeding transfer feeding meshing gear and the swing meshing locking mechanism are provided, and the feeding structure is configured with at least two sets of independent feeding channels. The injection head has a fixed origin positioning structure, which ensures high positioning repeatability. No origin offset calibration is required during the printing pause phase, and consumables and extruders can be replaced directly on the spot.

Images