Equipment for 3D printing of precast concrete component and control method thereof

Abstract

The invention provides equipment for 3D printing of precast concrete components and a control method thereof, and relates to the technical field of building automation, in order to solve the problem that in the prior art, the automation degree of precast concrete component production is insufficient, the equipment for 3D printing of precast concrete components comprises an automatic feeding device and a slurry preparing and conveying device, the conveying device is connected with the automatic feeding device and conveys to the 3D printing device; the 3D printing device is connected with the slurry preparing and conveying device and used for printing and forming the concrete slurry layer by layer into a prefabricated part according to the digital model; a reinforcement placement device; and the main controller is electrically connected with the automatic feeding device, the slurry preparing and conveying device, the 3D printing device and the reinforcing part placing device and used for cooperatively controlling automatic operation of all the devices. According to the equipment, the dependence on manpower and the production cost are obviously reduced, and the high automation of the whole process is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of building automation, and in particular to a device for 3D printing of concrete prefabricated components and a control method thereof. BACKGROUND

[0002] Concrete prefabricated components are an important part of modern building industrialization. The existing prefabricated component production mode mainly relies on molds for production, and the process usually includes assembly and fixation of molds, binding and placement of steel mesh, pouring and vibrating of concrete, etc., which requires a large amount of manual operation. This traditional production method has the defects of low production efficiency, high labor cost, large influence of human factors on product precision, poor quality consistency, etc. In addition, for components with complex shapes such as special-shaped and arc-shaped components, expensive special molds need to be customized, which not only has high cost and long cycle, but also is extremely inconvenient for storage and maintenance of the molds.

[0003] In recent years, concrete 3D printing technology has provided a new idea for solving the above problems. In the prior art, there have been schemes for using 3D printing devices and robots to cooperate. For example, in the 3D printing process, a robot is controlled to place reinforcing materials such as steel mesh on the printed structure when printing to a certain height, and then the printing is continued to realize the production of reinforced components. However, most of the above schemes focus on the cooperation of the two links of printing and reinforcing material placement, and there is still a lack of a highly integrated and seamless full-automatic solution for the front-end link from raw material supply to slurry preparation. This leads to insufficient automation of the entire production chain, poor connection between links, and still requires more manual intervention for feeding, monitoring and adjustment, which fails to fully realize the potential of automated production and limits the further improvement of production efficiency. SUMMARY

[0004] The purpose of the present application is to provide a device for 3D printing of concrete prefabricated components to solve the problem of insufficient automation of prefabricated component production in the prior art. The device for 3D printing of concrete prefabricated components of the present application significantly reduces the dependence on manpower and production cost, and realizes high automation of the whole process.

[0005] The device for 3D printing of concrete prefabricated components provided by the present application comprises an automatic feeding device for automatically feeding dry mixing materials to the device; A slurry preparation and conveying device is connected to the automatic feeding device for mixing the dry mixing materials with a liquid to prepare a concrete slurry and conveying the concrete slurry to a 3D printing device; A 3D printing device is connected to the slurry preparation and conveying device for printing the concrete slurry layer by layer according to a digital model to form a prefabricated component; The reinforcing member placing device is used for placing a reinforcing member at a specified position of the prefabricated component during printing. The main controller is electrically connected with the automatic feeding device, the slurry preparation and conveying device, the 3D printing device and the reinforcing member placing device respectively, and is used for cooperatively controlling the automatic operation of the devices. In the process of controlling the 3D printing device to perform layer-by-layer printing, the main controller is configured to interrupt the printing operation after printing to a predetermined height, control the reinforcing member placing device to place a reinforcing member on the printed structure, and then control the 3D printing device to continue the printing operation above the reinforcing member.

[0006] As a preferred scheme of the present application, the automatic feeding device comprises a first mechanical arm and a hopper, the hopper is arranged on one side of the first mechanical arm, a bag breaking blade is arranged at the inlet of the hopper, and a vibrator is arranged at the lower side of the hopper, the first mechanical arm can move a material bag above the bag breaking blade to cut the material bag and unload the material into the hopper.

[0007] As a preferred scheme of the present application, the slurry preparation and conveying device comprises a stirring pot, a stirring rod, a pumping hopper and a pump pipe, the stirring rod is arranged in the stirring pot, a discharge port is arranged at the bottom of the stirring pot, a discharge valve capable of opening or closing the discharge port is arranged at the discharge port, the pumping hopper is arranged below the discharge port of the stirring pot, and the pump pipe is connected with the outlet of the pumping hopper.

[0008] As a preferred scheme of the present application, the slurry preparation and conveying device further comprises a metering faucet, a camera and a liquid level sensor, the metering faucet and the camera are respectively connected to the upper edge of the stirring pot, and the liquid level sensor is installed on the pumping hopper, and the main controller is configured to judge the stirring effect according to the image of the camera and automatically control the discharge valve and the pumping start-stop according to the signal of the liquid level sensor.

[0009] As a preferred scheme of the present application, the 3D printing device comprises a gantry, a connecting cross bar and a printing head, the printing head is transversely movably installed on the connecting cross bar, the two ends of the connecting cross bar are vertically movably installed on the gantry, a spiral stirring shaft is arranged in the printing head, and the spiral stirring shaft is connected with a driving motor arranged above the printing head.

[0010] As a preferred scheme of the present application, the 3D printing device further comprises a liquid level monitoring device, the liquid level monitoring device is installed on the upper side of the printing head, and the main controller is configured to adjust the pumping speed of the slurry preparation and conveying device in real time according to the signal of the liquid level monitoring device to maintain the stable material level in the printing head.

[0011] As a preferred scheme of the present application, the printing head is movably connected to the connecting crossbar through a connecting frame, a laser positioner and a laser range finder are arranged on the lower side of the connecting frame, and the laser positioner and the laser range finder are used to automatically determine the printing origin and the printing starting height before printing.

[0012] As a preferred scheme of the present application, the reinforcing member is a steel mesh or a fiber mesh.

[0013] As a preferred scheme of the present application, the slurry preparation and conveying device further comprises an intelligent monitoring module, the intelligent monitoring module comprises a camera, a water mist spray head and a blowing port, and the main controller is configured to control the water mist spray head and the blowing port to clean the camera.

[0014] The present application also provides a control method of the device for the 3D printed concrete prefabricated component, and the control method comprises the following steps The 3D printing device is controlled to perform a layer-by-layer printing operation according to a preset path, the 3D printing device is supplied with concrete slurry by a slurry preparation and conveying device, and the slurry preparation and conveying device is supplied with dry mixed materials by an automatic feeding device; After the 3D printing device is printed to a predetermined height, the printing operation of the 3D printing device is interrupted; The reinforcing member placing device is controlled to move above the printed structure and place the reinforcing member on the printed structure; After the reinforcing member is placed, the 3D printing device is controlled to continue the printing operation above the reinforcing member until the component is formed.

[0015] Compared with the prior art, the present application has the following positive effects: The present invention provides a device for 3D printing precast concrete components, comprising: an automatic feeding device for automatically supplying dry mixed materials to the device; a slurry preparation and conveying device connected to the automatic feeding device for mixing the dry mixed materials with liquid to prepare a concrete slurry and conveying it to the 3D printing device; a 3D printing device connected to the slurry preparation and conveying device for printing the concrete slurry layer by layer into a precast component according to a digital model; a reinforcement placement device for placing reinforcements at designated positions on the precast component during the printing process; and a main controller electrically connected to the automatic feeding device, the slurry preparation and conveying device, the 3D printing device, and the reinforcement placement device for coordinating the automated operation of each device; wherein the main controller is configured to: during the layer-by-layer printing process of the 3D printing device, after printing to a predetermined height, interrupt the printing operation and control the reinforcement placement device to place a reinforcement on the printed structure, and then control the 3D printing device to continue printing above the reinforcement. This application highly integrates all key processes, including automatic material feeding, slurry preparation, component printing, and reinforcement implantation, and achieves fully automated collaborative operation through a main controller. This significantly reduces reliance on manpower and production costs, realizing a high degree of automation throughout the entire process. Direct 3D printing replaces traditional molds, eliminating the costs of mold customization, installation, dismantling, and storage, greatly improving production efficiency and flexibility, especially for the production of irregularly shaped and complex components. Furthermore, the entire process is precisely controlled by a computer, with closed-loop feedback control of slurry preparation and printing processes via sensors, eliminating human error and ensuring the accuracy of component dimensions and the stability of material quality. The "print-interrupt-reinforcement placement-continue printing" collaborative control method proposed in this application effectively solves the technical challenge of automatically implanting reinforcements in the 3D printing process, making the fully automated production of reinforced precast concrete components possible. Attached Figure Description

[0016] 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.

[0017] Figure 1 This is a schematic diagram of the equipment for 3D printing precast concrete components according to the present invention; Figure 2 This is a schematic diagram of the automatic feeding device in this invention; Figure 3This is a schematic diagram of the slurry preparation and conveying device in this invention; Figure 4 This is a schematic diagram of the intelligent monitoring module in this invention; Figure 5 This is a schematic diagram of the 3D printing device in this invention; Figure 6 This is a schematic diagram of the structure of the laser positioning device and the laser rangefinder in this invention; Figure 7 This is a schematic diagram of the main controller in this invention; Figure 8 This is a schematic diagram of the reinforcing member placement device in this invention; Figure 9 This is a block diagram of a printing-pumping closed-loop control provided in an embodiment of the present invention; Figure 10 A flowchart of a control method provided in an embodiment of the present invention. In the diagram: 1. Automatic feeding device; 11. First robotic arm; 12. Hopper; 13. Deburring blade; 14. Vibrator; 2. Slurry preparation and conveying device; 21. Mixing pot; 22. Mixing rod; 23. Metering tap; 24. Liquid level sensor; 25. Pumping bucket; 26. Pump pipe; 27. Screw conveyor; 28. Intelligent monitoring module; 281. Water mist nozzle; 282. Camera; 283. Air outlet; 3. 3D printing device; 31. Gantry frame; 32. Connecting crossbar; 33. Print head; 34. Connecting frame; 35. Liquid level monitoring device; 36. Laser positioning device; 37. Laser rangefinder; 4. Main controller; 5. Reinforcing part placement device; 51. Second robotic arm; 52. Reinforcing part; 6. Waste bin; 7. Material tray; 8. Mold table. Detailed Implementation

[0018] In the description of this invention, it should be noted that, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying it, 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, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0019] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0020] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0021] This embodiment provides a device for 3D printing precast concrete components, such as... Figures 1-8 As shown, specifically, the equipment is a highly integrated system, mainly comprising an automatic feeding device 1 for automatically supplying dry-mixed materials to the equipment; a slurry preparation and conveying device 2, connected to the automatic feeding device 1, for mixing the dry-mixed materials with liquids to prepare concrete slurry, and conveying it to the 3D printing device 3; the 3D printing device 3, connected to the slurry preparation and conveying device 2, for printing the concrete slurry layer by layer into precast components according to a digital model; a reinforcement 52 placement device for placing the reinforcement 52 at a designated position on the precast component during the printing process; and a main controller 4, which serves as the core of the system control. The main controller 4 is electrically connected to the automatic feeding device 1, the slurry preparation and conveying device 2, the 3D printing device 3, and the reinforcement 52 placement device, for coordinated control of the automated operation of each device. The main controller 4 is configured to: during the process of controlling the 3D printing device 3 to perform layer printing, after printing to a predetermined height, interrupt the printing operation, control the reinforcement 52 placement device to place a reinforcement 52 on the printed structure, and then control the 3D printing device 3 to continue the printing operation above the reinforcement 52.

[0022] The aforementioned devices can be physically arranged compactly and, through unified scheduling by the main controller 4, can achieve collaborative operation. The entire printing process takes place on a horizontal mold platform 8. It can be understood that the main controller 4 can be a high-performance industrial control computer running a comprehensive control software that integrates control logic for all subsystems, a human-machine interface, and data processing functions. The automatic feeding device 1, the slurry preparation and conveying device 2, the concrete 3D printing device 3, and the reinforcement placement device 5 are all electrically connected to the main controller 4 to receive its instructions and provide status feedback.

[0023] The 3D printing equipment for precast concrete components in this embodiment can replace traditional steel molds by printing the frame of precast components. Printing is performed by importing the component edge path map, which is particularly convenient for irregularly shaped or curved edge components, saving significant costs associated with custom molds. Because the concrete 3D printing material has high strength and a fast hardening speed, it can completely replace steel molds within 2 hours, and it becomes part of the component directly without needing to be demolded. For small components, internal concrete filling can also be performed; only the print head and admixture tray need to be replaced, eliminating the need for the mold to be moved to the pouring location or for transporting mortar hoppers for pouring. By highly integrating material handling, mixing, pumping, and 3D printing, all operations can be completed by one person using a single computer, greatly saving manpower and improving automation and intelligence.

[0024] As a preferred implementation method, such as Figure 1 As shown, the automatic feeding device 1 includes a first robotic arm 11 and a hopper 12. The hopper 12 is located on one side of the first robotic arm 11, and a bag-breaking blade 13 is provided at the inlet of the hopper 12. The bag-breaking blade 13 is connected to the inlet of the hopper 12 by a bracket, and the blade can be triangular to facilitate cutting the material bag. A vibrator 14 is provided on the lower side of the hopper 12. Under the vibration of the vibrator 14, the material can fall smoothly from the outlet of the hopper 12 into the slurry preparation and conveying device 2. The first robotic arm 11 can move the material bag above the bag-breaking blade 13 to cut the material bag and unload the material into the hopper 12. The first robotic arm 11 is equipped with movement in three directions (X, Y, and Z) to facilitate picking up and moving the material. Specifically, a material tray 7 and a waste bin 6 are provided next to the first robotic arm 11. The material tray 7 is used to stack material packages, and the first robotic arm 11 grabs material packages from the material tray 7. The waste bin 6 is used to hold empty bags. After the first robotic arm 11 unloads material into the hopper, the empty bags are transferred to the waste bin 6 and discarded.

[0025] As a preferred implementation method, such as Figure 2 As shown, the slurry preparation and conveying device 2 includes a mixing pot 21, a stirring rod 22, a pumping hopper 25, and a pump pipe 26. The stirring rod 22 is disposed in the mixing pot 21. The length of the stirring rod 22 is adapted to the radius of the mixing pot 21 to achieve thorough mixing of the material in the mixing pot. A discharge port is provided at the bottom of the mixing pot 21, and a discharge valve that can open or close the discharge port is provided at the discharge port. The pumping hopper 25 is disposed below the discharge port of the mixing pot 21, and the pump pipe 26 is connected to the outlet of the pumping hopper 25. A screw conveyor 27 is disposed in the pumping hopper 25, and the screw conveyor is disposed below the discharge port. The screw conveyor is coaxially arranged with the pump pipe 26 to convey the material into the pump pipe 26. A conveying pump is disposed on the pump pipe 26, and the slurry in the pump pipe is conveyed to the 3D printing device 3 by the conveying pump.

[0026] As a preferred implementation method, such as Figure 2 As shown, the slurry preparation and conveying device 2 also includes a metering tap 23, a camera 282, and a level sensor 24. The metering tap 23 and the camera 282 are respectively connected to the upper edge of the mixing pot 21, and the level sensor 24 is installed on the pumping hopper 25. The level sensor 24 is used to monitor the slurry level in the pumping hopper 25. The main controller 4 is configured to determine the mixing effect based on the image from the camera 282 and automatically control the discharge valve and pump start / stop based on the signal from the level sensor 24.

[0027] As a preferred implementation method, such as Figure 3 As shown, the 3D printing device 3 includes a gantry frame 31, a connecting crossbar 32, and a print head 33. The print head 33 is horizontally movable and mounted on the connecting crossbar 32, and both ends of the connecting crossbar 32 are vertically movable and mounted on the gantry frame 31 to achieve multi-directional movement of the 3D printing device 3. In this embodiment, the concrete 3D printing device 3 adopts a high-rigidity gantry frame 31 structure to ensure the stability and positioning accuracy of the print head 33 during movement within a large area (e.g., 4 meters × 4 meters). A spiral stirring shaft is provided inside the print head 33, and the spiral stirring shaft is connected to a drive motor located above the print head 33. The drive motor can drive the spiral stirring shaft to stir the material in the print head 33 to achieve uniformity of the material in the print head 33.

[0028] As a preferred implementation method, such as Figure 3 As shown, the 3D printing device 3 also includes a liquid level monitoring device 35, which is installed on the upper side of the print head 33. The main controller 4 is configured to adjust the pumping speed of the slurry preparation and conveying device 2 in real time according to the signal of the liquid level monitoring device 35, so as to maintain the stability of the material level in the print head 33.

[0029] To address the issue of uneven material output that may occur during 3D printing, an improved solution is proposed. This solution aims to achieve precise dynamic adjustment of the printing flow rate through closed-loop feedback control, thereby significantly improving print quality.

[0030] In the concrete 3D printing process, the slurry travels from the pump hopper 25 through a relatively long pump pipe 26 to the print head 33. Pressure loss in the pipe is affected by various factors, including pipe length, degree of curvature, slurry viscosity fluctuations, and printing speed variations. In open-loop control mode, it is difficult to ensure a constant output speed from the print head 33, which can easily lead to defects such as inconsistent line thickness, discontinuity, or accumulation, thus affecting the forming accuracy and mechanical properties of the component. To address this issue, this embodiment optimizes the structure of the print head 33 of the concrete 3D printing device 3. Please refer to [link / reference]. Figure 5A small slurry buffer chamber is provided inside the printhead 33, and a liquid level monitoring device 35 is installed thereon. The liquid level monitoring device 35 can be a non-contact ultrasonic sensor or a laser rangefinder sensor. Its function is to measure the liquid level height of the slurry in the buffer chamber in real time and at high frequency. Its signal output terminal is electrically connected to the main controller 4.

[0031] The core control logic of this embodiment is as follows: Figure 9 The block diagram of the print-pump closed-loop control is shown. This control system consists of software algorithms and related hardware within the main controller 4. The main controller 4 presets an ideal liquid level height as a "set value," which represents the optimal buffer amount to generate the most stable extrusion pressure. The liquid level monitoring device 35 acts as a feedback loop, feeding back the real-time measured slurry level as a "measured value" to the "comparator" module within the main controller 4. The comparator compares the "set value" with the "measured value" and calculates the "deviation signal" between the two.

[0032] Specifically, during the printing process, when a disturbance (such as increased material demand due to accelerated printhead movement) causes the actual material level in the printhead 33 to drop, the liquid level monitoring device 35 will detect that the material level is below the set value and generate a positive deviation signal. In response to this positive deviation signal, the PID controller increases its output to instruct the frequency converter to increase the speed of the pump motor, thereby increasing the slurry supply and causing the material level to rise again. Conversely, when the material level is above the set value, a negative deviation signal is generated, and the PID controller will reduce the pump speed to decrease the material supply, thus causing the material level to drop. Through this continuous and rapid dynamic adjustment, the system can always maintain the material level (i.e., ...) in the printhead 33 buffer chamber. Figure 9 The "controlled object" in the system is precisely maintained within a very small fluctuation range around the set value.

[0033] By introducing this closed-loop feedback control mechanism based on printhead material level monitoring, this embodiment achieves precise control of the printing output flow rate, effectively suppressing the impact of various disturbance factors on printing stability. Its beneficial effects include: the printed concrete lines have uniform width and smooth surfaces, with tight bonding between layers, greatly improving the dimensional accuracy, appearance quality, and structural integrity of the precast components.

[0034] As a preferred implementation method, such as Figure 6As shown, the print head 33 is movably connected to the connecting crossbar 32 via a connecting bracket 34. A laser positioning device 36 and a laser rangefinder 37 are located on the lower side of the connecting bracket 34. The laser positioning device 36 and laser rangefinder 37 are used to automatically determine the printing origin and printing start height before printing. The laser positioning device 36 and laser rangefinder 37 integrated on the print head 33 emit laser beams to scan preset marker points on the die 8, thereby automatically establishing the origin of the printing coordinate system. Simultaneously, they measure the vertical distance from the print head nozzle to the surface of the die 8 to accurately set the printing start height. This eliminates the need for extensive adjustments and manual measurements.

[0035] As a preferred implementation method, such as Figure 8 As shown, the reinforcement placement device 5 includes a second robotic arm 51 and a reinforcement 52. The second robotic arm 51 is capable of moving in three directions (X, Y, and Z) to facilitate picking up and moving the reinforcement 52.

[0036] In a preferred embodiment, the reinforcement 52 is a steel mesh or a fiber mesh.

[0037] In a preferred embodiment, the slurry preparation and conveying device 2 further includes an intelligent monitoring module 28, which includes a camera 282, a water mist nozzle 281, and an air outlet 283. The main controller 4 is configured to control the water mist nozzle 281 and the air outlet 283 to clean the camera 282.

[0038] To address the reliability issue of visual monitoring in the slurry preparation process, an intelligent monitoring module with self-cleaning function is proposed to ensure the long-term stable operation of the monitoring system in high-dust environments, thereby further improving the system's automation and intelligence level.

[0039] During slurry preparation, a large amount of dust is instantly generated when the dry-mixed materials are added to the mixing pot 21 and water is added for stirring. This dust quickly adheres to the lens of the camera used to monitor the stirring status, resulting in blurry images and making the image-based judgment of the stirring effect unreliable. The traditional method of manually wiping the lens periodically not only contradicts the design concept of full automation but also interrupts production.

[0040] To address this issue, this embodiment features a specially designed intelligent monitoring module 28 in the slurry preparation and conveying device 2. For example... Figure 3 and Figure 4 As shown, Figure 4This is an enlarged schematic diagram of the intelligent monitoring module 28. This module can be designed as a compact integrated unit, mounted on the top cover of the mixing tank 21 to overlook the tank interior. It integrates three core components: a high-definition industrial camera 282, a water mist nozzle 281, and a compressed air outlet 283. The camera 282 captures images of the slurry; the water mist nozzle 281 connects to a small water pump and water source; and the air outlet 283 connects to the factory's compressed air source. The switching on and off of the water mist nozzle 281 and the air outlet 283 are controlled by the main controller 4 via solenoid valves.

[0041] The main controller 4 has an embedded automatic cleaning program for the camera 282. This program can be triggered in two ways: first, time-based periodic triggering, such as setting it to run automatically every time a batch of ingredients is stirred or every 10 minutes; second, on-demand triggering, where the image processing software in the main controller 4 analyzes the video stream from the camera 282 in real time, and calculates indicators such as image clarity, contrast, or edge sharpness in specific areas. Once the image quality is found to have dropped below a preset threshold, the cleaning program is automatically started.

[0042] This cleaning process ensures that the lens of camera 282 remains clean even under harsh stirring conditions. Correspondingly, the main controller 4 continuously acquires high-quality images of the slurry and analyzes its color, gloss, flow pattern, and adhesion to the stirring blades using advanced image processing algorithms. This allows for real-time and accurate judgment of whether the slurry is uniformly stirred and whether the slump is appropriate, achieving intelligent closed-loop monitoring and quality control of the slurry preparation process. This not only avoids manual intervention and ensures production continuity but also guarantees the consistency of slurry performance in each batch, laying a solid material foundation for subsequent high-quality printing.

[0043] This embodiment also provides a control method for the equipment for 3D printing precast concrete components, characterized by including the following steps: The 3D printing device 3 is controlled to perform layer printing according to a preset path. The 3D printing device 3 is supplied with concrete slurry by a slurry preparation and conveying device 2, and the slurry preparation and conveying device 2 is supplied with dry mixed material by an automatic feeding device 1. After the 3D printing device 3 prints to a predetermined height, the printing operation of the 3D printing device 3 is interrupted. The reinforcing member 52 placement device is moved above the printed structure and the reinforcing member 52 is placed on the printed structure; After the reinforcement 52 is placed, the 3D printing device 3 is controlled to continue printing above the reinforcement 52 until the component is formed.

[0044] In one embodiment of this application, the core process of the cooperative control method executed by the main controller 4 can be referred to... Figure 10 As shown, the specific steps may include: First, in step S20, the operator imports the digital model of the precast component to be produced and sets relevant process parameters through the human-machine interface of the main controller 4. This digital model is typically a 3D CAD model generated by slicing software, producing a layer-by-layer printing path file (e.g., G-code format), which includes the movement trajectory of the print head in X, Y, and Z three-dimensional space. The set parameters include, but are not limited to: printing layer height (e.g., 10 mm), printing speed (e.g., 200 mm / s), slurry formulation (e.g., water-cement ratio), and the predetermined height at which reinforcement components need to be implanted.

[0045] After parameter settings are completed and the operation is started, the system enters fully automatic operation mode. The main controller 4 first executes step S30, instructing the automatic feeding device 1 to begin operation. (Refer to...) Figure 1 Under the command of the main controller 4, the first robotic arm 11, equipped with a gripper at its end, moves to the pre-set material tray and grabs a bag of premixed quick-setting concrete dry mix weighing approximately 50-60 kg. The first robotic arm 11 then transports the bag to directly above the feeding hopper 12, where the bag's own weight cuts through the sharp bag-breaking blade 13, causing the bag to break open and the dry mix material inside to pour into the feeding hopper 12. To prevent the material from sticking or arching against the hopper wall, a vibrator 14 can be installed at the bottom of the feeding hopper 12. The main controller 4 can intermittently activate the vibrator 14 as needed to ensure the material falls smoothly into the slurry preparation and conveying device 2 below.

[0046] Subsequently, step S40 is executed to prepare and transport the slurry. For example... Figure 3 and Figure 4As shown, the slurry preparation and conveying device 2 is used to receive dry mixed materials from the automatic feeding device 1. This device mainly includes a mixing pot 21, a pumping hopper 25, and related sensing and control components. After the dry mixed materials enter the mixing pot 21, the main controller 4 precisely controls the electromagnetic water valve connected to the mixing pot 21 to add a fixed amount of water according to the preset water-cement ratio. Then, the stirring rod 22 inside the mixing pot 21 drives the paddles to rotate at high speed, forcibly mixing the materials and water. During the mixing process, the camera in the intelligent monitoring module 28 installed above the mixing pot 21 transmits real-time images of the slurry inside the pot to the main controller 4, so that the operator or the image recognition algorithm built into the control system can determine whether the uniformity and flowability of the slurry meet the printing requirements. After mixing is completed, the discharge valve at the bottom of the mixing pot 21 opens, and the prepared concrete slurry flows into the pumping hopper 25. When the material level reaches the upper limit, the liquid level sensor 24 sends a signal to the main controller 4, which can instruct the mixing pot 21 to pause discharge; when the material level is below the lower limit, it indicates that a new batch of slurry needs to be prepared. The pumping bucket 25 (e.g., a screw pump) is activated under the command of the main controller 4, pumping the slurry in the pumping bucket to the print head of the concrete 3D printing device 3 through a flexible conveying pipe.

[0047] Next, step S50 is executed, proceeding to the core printing stage. Please refer to [link / reference]. Figure 5 In this embodiment, the concrete 3D printing device 3 employs a high-rigidity gantry structure 31 to ensure the stability and positioning accuracy of the print head 33 within a large area (e.g., 4m x 4m). Before the formal printing begins, to eliminate manual positioning errors, the main controller 4 initiates an automatic calibration program. The laser positioning device 36 and laser rangefinder 37 integrated on the print head 33 emit laser beams to scan preset marker points on the mold table 8, thereby automatically establishing the origin of the printing coordinate system. Simultaneously, the vertical distance from the print head nozzle to the surface of the mold table 8 is measured to precisely set the starting height of printing (Z=0). After calibration, the print head 33 begins to extrude the first layer of concrete slurry onto the mold table 8 according to the path defined by the digital model. After each layer is printed, the Z-axis is raised by one layer height, and the next layer is printed, thus repeating the cycle, and the height of the component continuously increases. It should be noted that the fast-hardening high-strength concrete material used in this embodiment has a short initial setting time and rapid early strength development, ensuring that the lower structure can withstand the weight of the upper structure without collapsing.

[0048] During the printing process, the main controller 4 monitors the current number of printing layers or the printing height in real time and executes the judgment in step S60. When the printing height reaches the previously set predetermined height (for example, the 10th layer is printed), the judgment condition is met, and the process proceeds to step S70. At this time, the main controller 4 immediately sends a command to the concrete 3D printing device 3 to interrupt printing. The printer then stops pumping and print head movement, and raises the print head 33 upward along the Z-axis a safe distance, then moves it to a standby position outside the working area to make room for subsequent reinforcement placement operations.

[0049] Accordingly, the main controller 4 executes step S80, instructing the reinforcement placement device 5 to perform its operation. For example... Figure 8 As shown, the reinforcement placement device 5 in this embodiment includes a dedicated second robotic arm 51, the structure and load capacity of which are selected according to the type and weight of the reinforcement used. A specialized clamp is installed at its end. In this example, the reinforcement is a pre-processed steel mesh. The second robotic arm 51 precisely picks up a piece of steel mesh from the adjacent rack, adjusts the posture of the steel mesh using its six-axis linkage function, then smoothly moves it directly above the printed concrete structure and slowly lowers it, accurately placing it on the top surface of the 10th layer of the printed body. The placement accuracy can be ensured by the robotic arm's own encoder or vision guidance system.

[0050] After the reinforcement placement device 5 completes its placement task and leaves the work area, it sends a work completion signal to the main controller 4. Upon receiving this signal, the main controller 4 executes step S90, instructing the concrete 3D printing device 3 to return to its work position. The print head 33 moves to the interruption point, descends to a suitable height, and then resumes slurry pumping and print head movement, beginning to print the 11th layer above the placed reinforcing mesh. The slurry fills and completely covers the mesh of the reinforcing mesh, thus firmly encasing the reinforcement inside the component. Afterward, the process returns to step S50 to continue the printing operation until all layers of the entire component are printed. When the final determination of printing completion is made, the process ends at step S100.

[0051] The equipment and method of this embodiment enable the fully automated production of precast concrete components with embedded steel mesh. Specifically, this embodiment can be used to print the frame of precast components. This frame is printed using fast-hardening concrete material, achieving sufficient structural strength within approximately two hours of printing. It can be used directly as a permanent formwork for subsequent large-volume concrete pouring, i.e., a formwork that does not require removal. This solution not only eliminates the expensive mold costs and cumbersome mold-setting and dismantling processes of traditional production methods, significantly improving production efficiency, but also makes the production of irregularly shaped and curved components of any form simple and quick, demonstrating significant technical advantages and application value.

[0052] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications and improvements made by those skilled in the art without departing from the inventive concept of the present invention should be covered within the scope of protection of the present invention.

Claims

1. An apparatus for 3D printing of concrete precast elements, characterized by, The application relates to a 3D printing device for prefabricated components, comprising an automatic feeding device for automatically feeding dry mixed materials to the device; a slurry preparation and conveying device connected with the automatic feeding device, for mixing the dry mixed materials with liquid to prepare concrete slurry and conveying the concrete slurry to a 3D printing device; a 3D printing device connected with the slurry preparation and conveying device, for printing the concrete slurry into a prefabricated component according to a digital model layer by layer; a reinforcing member placing device for placing reinforcing members at designated positions of the prefabricated component during printing; a main controller electrically connected with the automatic feeding device, the slurry preparation and conveying device, the 3D printing device and the reinforcing member placing device respectively, for controlling the automatic operation of the devices; wherein the main controller is configured to, during the process of controlling the 3D printing device to print layer by layer, interrupt the printing operation after printing to a predetermined height, control the reinforcing member placing device to place a reinforcing member on the printed structure, and then control the 3D printing device to continue the printing operation above the reinforcing member.

2. The apparatus of claim 1, wherein, The automatic feeding device comprises a first mechanical arm and a hopper, the hopper is arranged on one side of the first mechanical arm, a bag breaking blade is arranged at the inlet of the hopper, and a vibrator is arranged at the lower side of the hopper; the first mechanical arm can move a material bag above the bag breaking blade to cut the material bag and unload the material into the hopper.

3. The apparatus of claim 1, wherein, The slurry preparation and conveying device comprises a stirring pot, a stirring rod, a pumping hopper and a pump pipe; the stirring rod is arranged in the stirring pot, a discharge port is arranged at the bottom of the stirring pot, a discharge valve capable of opening and closing the discharge port is arranged at the discharge port, the pumping hopper is arranged below the discharge port of the stirring pot, and the pump pipe is connected with the outlet of the pumping hopper.

4. The apparatus of claim 3, wherein, The slurry preparation and conveying device further comprises a metering faucet, a camera and a liquid level sensor; the metering faucet and the camera are respectively connected to the upper edge of the stirring pot, and the liquid level sensor is mounted on the pumping hopper; the main controller is configured to judge the stirring effect according to the image of the camera and automatically control the discharge valve and the pumping start-stop according to the signal of the liquid level sensor.

5. The apparatus of claim 1, wherein, The 3D printing device comprises a gantry, a connecting crossbar and a printing head; the printing head is transversely movably arranged on the connecting crossbar, the two ends of the connecting crossbar are vertically movably arranged on the gantry, a spiral stirring shaft is arranged in the printing head, and the spiral stirring shaft is connected with a driving motor arranged above the printing head.

6. A device for 3D printing of concrete precast elements according to claim 5, characterized in that, The 3D printing device further comprises a liquid level monitoring device mounted on the upper side of the printing head; the main controller is configured to adjust the pumping speed of the slurry preparation and conveying device in real time according to the signal of the liquid level monitoring device to maintain the stable material level in the printing head.

7. A device for 3D printing of concrete prefabricated elements according to claim 6, characterized in that, The printing head is movably connected to the connecting crossbar through a connecting frame; a laser positioner and a laser range finder are arranged at the lower side of the connecting frame, and the laser positioner and the laser range finder are used for automatically determining the printing origin and the printing starting height before printing.

8. The apparatus of claim 1, wherein, The reinforcement is a steel mesh or a fiber mesh.

9. The apparatus of claim 3, wherein, The slurry preparation and conveying device further comprises an intelligent monitoring module, the intelligent monitoring module comprises a camera, a water mist spray head and a blowing port; the main controller is configured to control the water mist spray head and the blowing port to clean the camera.

10. A control method of the apparatus for 3D printing concrete precast members according to any one of claims 1 to 9, characterized in that, comprising the steps of controlling a 3D printing device to perform a layer-by-layer printing operation according to a preset path, the 3D printing device being supplied with a concrete slurry by a slurry preparation and conveying device, the slurry preparation and conveying device being supplied with dry-mixed materials by an automatic feeding device; after the 3D printing device prints to a predetermined height, interrupting the printing operation of the 3D printing device; controlling a reinforcement placement device to move above the printed structure and place a reinforcement on the printed structure; after the reinforcement placement is completed, controlling the 3D printing device to continue the printing operation above the reinforcement until a component is formed.

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