Multi-axis motion 3D printing equipment and printing method

Abstract

The invention provides multi-axis motion 3D printing equipment and a printing method. The multi-axis motion 3D printing equipment comprises a mounting bracket, a forming bin is mounted at the top of the mounting bracket, a multi-axis motion part is mounted in the forming bin, and a powder feeding and printing part is mounted on the multi-axis motion part; a forming platform is arranged at the position, corresponding to the powder feeding and printing part, in the bottom end face of the forming bin, and a telescopic part is mounted at the bottom of the forming platform and mounted in the mounting support. A monitoring system is arranged on the forming bin, the monitoring system is in communication connection with the powder feeding and printing part and the multi-axis movement part, and the monitoring system is used for detecting the real-time temperature and the real-time uniformity of the fused powder on the forming platform in real time and adjusting working parameters of the powder feeding and printing part and the multi-axis movement part based on the real-time temperature. The multi-axis moving part is matched with the telescopic part to achieve powder feeding in the multi-axis direction, then powder is laid layer by layer, the laid powder is evenly laid, then the molten pool is formed through the molten powder in the multi-axis direction, the uniformity of the molten pool is improved, and the printing quality and the printing efficiency are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of 3D printing equipment, and more particularly to a multi-axis motion 3D printing equipment and a printing method. Background Art

[0002] Additive manufacturing technology, namely 3D printing technology, as a rapid prototyping technology, has been widely used and developed rapidly in recent years. Its core is to produce complex three-dimensional objects by layer-by-layer building of materials. This layer-by-layer stacking forming method is different from traditional subtractive manufacturing and isostatic manufacturing, and has advantages in improving material utilization rate, optimizing structural design freedom, and shortening manufacturing cycle. The main application scenarios of additive manufacturing include multiple fields such as aerospace, medical devices, automotive parts, and industrial mold manufacturing.

[0003] Powder bed fusion (PBF), as one of the typical additive manufacturing technologies, is a process of constructing three-dimensional objects by layer-by-layer melting of metal or polymer powders using high-energy lasers or electron beams. In the PBF process, the 3D printing equipment first evenly spreads the powder material on the forming platform, and then selectively melts the laid powder according to the preset scanning path to form the target shape; after each layer of powder is melted and solidified, the distance between the print head and the forming table is adjusted to print the next layer structure until the construction is completed.

[0004] Currently, in the actual application process, powder feeding and melting usually rely on single-direction powder laying and directional melting. Due to the limitations of powder fluidity and the influence of gravity, it is easy to cause phenomena such as uneven powder distribution and particle accumulation in the melting area. Furthermore, the material uniformity of the printed parts cannot be guaranteed, affecting the melting quality of the parts and resulting in unevenness of material forming. Especially when printing large-area parts, the uneven powder distribution is more obvious, resulting in poor performance of the printed large-area parts, not meeting the usage requirements of large-area parts, and high manufacturing costs. Summary of the Invention

[0005] In order to solve the problem that in the existing additive printing equipment, powder feeding and melting usually rely on single-direction powder laying and directional melting, resulting in uneven powder distribution and particle accumulation in the melting area, and causing the printed parts to be defective products, the present invention provides a multi-axis motion 3D printing equipment and a printing method to achieve multi-axis powder feeding and melting, so as to complete the uniform laying of powder during the printing process and avoid particle accumulation in the melting area, and improve the material uniformity in the printed parts.

[0006] To achieve the above object, the present invention provides the following technical solutions: The present invention provides a multi-axis motion 3D printing device, including a mounting bracket. A forming chamber is installed on the top of the mounting bracket. A multi-axis motion part is installed in the forming chamber, and a powder feeding and printing part is installed on the multi-axis motion part. On the bottom end face of the forming chamber, a forming platform is arranged corresponding to the position of the powder feeding and printing part. A telescopic part is installed at the bottom of the forming platform, and the telescopic part is installed in the mounting bracket. A monitoring system is arranged on the forming chamber. The monitoring system is communicatively connected to the powder feeding and printing part and the multi-axis motion part. The monitoring system is used to detect the real-time temperature and real-time uniformity after the powder on the forming platform is melted in real time, and adjust the working parameters of the powder feeding and printing part and the multi-axis motion part based on the real-time temperature.

[0007] Preferably, the multi-axis motion part includes a first moving part. The moving direction of the first moving part is perpendicular to the moving direction of the telescopic part. The first moving part is installed on the inner wall of the forming chamber. A first synchronous belt connecting seat is installed on the first moving part, and a second moving part is installed in the first synchronous belt connecting seat. The moving direction of the second moving part is perpendicular to the moving direction of the first moving part and the moving direction of the telescopic part respectively. The powder feeding and printing part is installed on the second moving part.

[0008] Preferably, the first moving part includes a first servo motor. The first servo motor is installed in the forming chamber. A first belt pulley is connected to the output shaft of the first servo motor. A second belt pulley is arranged at the same height as the first belt pulley in the forming chamber. A first transmission belt is connected between the first belt pulley and the second belt pulley, and one end of the first synchronous belt connecting seat is connected to the first transmission belt. The second moving part includes a first electric slide table. The first electric slide table is installed in the first synchronous belt connecting seat. A first printing connecting plate is connected to the first electric slide table, and the powder feeding and printing part is installed on the first printing connecting plate.

[0009] Preferably, the multi-axis motion part includes a third moving part and a fourth moving part. The moving direction of the third moving part is perpendicular to the moving direction of the telescopic part. The moving direction of the fourth moving part is perpendicular to the moving direction of the third moving part and the moving direction of the telescopic part respectively. The third moving part is installed on the inner wall of the forming chamber. A second synchronous belt connecting seat is installed on the third moving part, and the powder feeding and printing part is installed on the second synchronous belt connecting seat. The fourth moving part is installed above the forming platform.

[0010] Preferably, the third moving member includes a second servo motor installed inside the forming chamber. A third pulley is connected to the output shaft of the second servo motor. A fourth pulley is provided inside the forming chamber at the same height as the third pulley. A second transmission belt is connected between the third pulley and the fourth pulley. One end of the second synchronous belt connecting seat is connected to the second transmission belt; The fourth moving member includes a second electric slide table installed above the forming platform. A printing platform is installed on the second electric slide table.

[0011] Preferably, the telescopic part includes a telescopic rod. An installation groove is provided on the bottom end surface of the forming chamber. One end of the telescopic rod where the telescopic head is located passes through the installation groove and is connected to the forming platform inside the forming chamber; A seal is installed in the installation groove. A seal groove is provided on the seal. One end of the telescopic rod where the telescopic head is located passes through the seal groove; The other end of the telescopic rod is fixed to the installation bracket.

[0012] Preferably, the powder feeding and printing part includes an energy beam printing head installed on the multi-axis moving part. An annular powder feeder is provided at the lower end of the energy beam printing head. A powder conveying pipe is provided at the top of the annular powder feeder. The powder conveying pipe is externally connected to a powder conveyor through a pipeline.

[0013] Preferably, an adsorber is provided near the top of the energy beam printing head. The adsorber is communicatively connected to a dust concentration sensor installed inside the forming chamber; The dust concentration sensor is used to detect the dust concentration inside the forming chamber. Based on the dust concentration, it controls the adsorber to absorb the powdered material that spills out inside the forming chamber; Among them, the adsorber is one of an electromagnetic adsorber or a vacuum cleaner.

[0014] Preferably, the monitoring system includes an oxygen sensor, a closed-loop temperature control module, and a detection and adjustment module; The oxygen sensor is installed on the forming chamber and is used to detect the oxygen concentration inside the forming chamber; The closed-loop temperature control module includes a temperature sensor and a controller. The controller is communicatively connected to the temperature sensor and the powder feeding and printing part; Among them, the temperature sensor is used to collect the temperature of the molten pool formed after the powder is melted; The controller is configured to control the laser or electron beam power for melting the powder material input on the powder feeding and printing unit by acquiring the temperature data collected by the temperature sensor. The detection and adjustment module includes a detector and a regulator. The regulator is communicatively connected to the detector, the powder feeding and printing unit, and the multi-axis motion unit. Wherein, the detector is used for the uniformity of the molten pool formed after the powder material is melted. The regulator is configured to control the powder feeding rate of the powder feeding and printing unit and the moving speed of the multi-axis motion unit by acquiring the uniformity collected by the detector.

[0015] The present invention provides a multi-axis motion 3D printing method, which is applied to the above-mentioned multi-axis motion 3D printing device, and includes the following steps: Transport the powder material to the powder feeding and printing unit in the forming chamber based on the powder feeding amount set according to the manufacturing parameters. Drive the multi-axis motion unit to drive the powder feeding and printing unit to move above the forming platform based on the powder material trajectory set according to the manufacturing parameters, and lay the powder material layer by layer; perform a first melting scan on the powder material laid layer by layer based on a preset first preset trajectory, and perform a second melting scan on the powder material laid layer by layer according to a preset second preset trajectory to obtain a finally formed three-dimensional object; wherein, the monitoring system real-time detects the real-time temperature and real-time uniformity after the powder material on the forming platform is melted, and adjusts the working parameters of the powder feeding and printing unit and the multi-axis motion unit based on the real-time temperature.

[0016] Compared with the prior art, the present invention has the following beneficial technical effects: The present invention provides a multi-axis motion 3D printing device. The forming chamber stably supported by the mounting bracket provides a solid foundation for the entire printing system, ensuring the stable progress of the printing operation. The integration of the multi-axis motion unit enables the powder feeding and printing unit to accurately move along complex trajectories in three-dimensional space, making the powder material laid layer by layer uniform, realizing high-precision and complex structure printing, improving the printing quality and printing efficiency. The ingenious combination of the powder feeding and printing unit and the forming platform, through the flexible adjustment of the telescopic part, not only ensures the uniform distribution of the powder material during the printing process, but also effectively controls the height of the forming platform to meet the requirements of different printing layers, improves the printing efficiency, and significantly enhances the interlayer bonding strength of the printed parts, thereby enhancing the overall structural stability. The monitoring system can real-time monitor the real-time temperature and uniformity after the powder material on the forming platform is melted. Based on these real-time data, the monitoring system can intelligently adjust the working parameters of the powder feeding and printing unit and the multi-axis motion unit, such as the powder feeding rate, laser power, moving speed, etc., to ensure that the printing process is always in the optimal state, making the uniformity of the molten pool formed by the melting of the powder material high, and thus improving the printing quality; this device realizes the comprehensive improvement of printing accuracy, efficiency and quality.

[0017] Further, in this device, an adsorber is used to adsorb the powdered materials overflowing in the forming chamber, reducing the waste and overflow of the powdered materials.

[0018] Furthermore, in this device, the detection and adjustment module collects the uniformity of the molten pool formed after the melting of the powdered materials in real time and dynamically adjusts the powder feeding rate and melting parameters of the powder feeding and printing unit, improving the uniformity of each layer of molten pool. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic structural diagram of an embodiment of a multi-axis motion 3D printing device proposed by the present invention; Figure 2 It is a front view structural schematic diagram of an embodiment of a multi-axis motion 3D printing device proposed by the present invention; Figure 3 It is a side view structural schematic diagram of an embodiment of a multi-axis motion 3D printing device proposed by the present invention; Figure 4 It is a top view structural schematic diagram of an embodiment of a multi-axis motion 3D printing device proposed by the present invention; Figure 5 It is an installation schematic diagram of the multi-axis motion part in an embodiment of a multi-axis motion 3D printing device proposed by the present invention; Figure 6 It is one of the structural schematic diagrams of the multi-axis motion part in an embodiment of a multi-axis motion 3D printing device proposed by the present invention; Figure 7 It is the second structural schematic diagram of the multi-axis motion part in an embodiment of a multi-axis motion 3D printing device proposed by the present invention; Figure 8 It is the structural schematic diagram of the multi-axis motion part in another embodiment of a multi-axis motion 3D printing device proposed by the present invention; Figure 9 It is the installation schematic diagram of the multi-axis motion part in another embodiment of a multi-axis motion 3D printing device proposed by the present invention; Figure 10 It is one of the structural schematic diagrams of the multi-axis motion part in another embodiment of a multi-axis motion 3D printing device proposed by the present invention; Figure 11 It is the second structural schematic diagram of the multi-axis motion part in another embodiment of a multi-axis motion 3D printing device proposed by the present invention; Figure 12 It is the connection schematic diagram of the powder feeding and printing unit and the adsorber in a multi-axis motion 3D printing device proposed by the present invention; In the accompanying drawings: 10, mounting bracket; 11, forming chamber; 110, mounting groove; 12, seal; 120, sealing groove; 13, forming platform; 14, powder conveying pipe; 15, moving part; 20, multi-axis moving part; 200, first moving member; 200-1, first servo motor; 200-2, first pulley; 200-3, second pulley; 200-4, first transmission belt; 201, first synchronous belt connecting seat; 202, second moving member; 202-1, first electric slide; 202-2, first printing connecting plate; 203, third moving member; 203-1, second servo motor; 203-2, third pulley; 203-3, fourth pulley; 203-4, second transmission belt; 204, second synchronous belt connecting seat; 205, fourth moving member; 205-1, second electric slide; 205-2, printing platform; 21, powder feeding and printing part; 210, energy beam printing head; 211, annular powder feeder; 22, telescopic part; 23, oxygen sensor; 24, adsorber. Detailed implementation manners

[0020] In the following, only some exemplary embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the present invention. Therefore, the drawings and the description are considered to be exemplary in nature rather than restrictive.

[0021] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation of the present invention.

[0022] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality of" means two or more unless otherwise specifically defined.

[0023] In the present invention, unless otherwise clearly specified or limited, the terms "installed", "connected", "joined", "fixed", etc. shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection, an electrical connection, or a communication connection; it may be directly connected, or indirectly connected through an intermediate medium, and may be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] In the present invention, unless otherwise clearly specified or limited, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "beneath" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.

[0025] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0026] The present invention provides a multi-axis motion 3D printing device, which includes an installation bracket 10. A forming chamber 11 is installed on the top of the installation bracket 10. The forming chamber 11 is the processing area of the 3D printing device, responsible for accommodating metal powder and three-dimensional objects. In this area, the metal powder is laid layer by layer, and the energy beam selectively melts it to form a three-dimensional structure stacked layer by layer. The forming chamber 11 needs to have airtightness to prevent the outside air from affecting the printing quality and avoid the oxidation of metal powder at the same time. A multi-axis motion part 20 is installed in the forming chamber 11, and a powder feeding and printing part 21 is installed on the multi-axis motion part 20. A forming platform 13 is arranged at a position corresponding to the powder feeding and printing part 21 on the bottom end face of the forming chamber 11. A telescopic part 22 is installed at the bottom of the forming platform 13, and the telescopic part 22 is installed in the installation bracket 10. A monitoring system is arranged on the forming chamber 11. The monitoring system is communicatively connected to the powder feeding and printing part 21 and the multi-axis motion part 20. The monitoring system is used to detect the real-time temperature and real-time uniformity of the powder after melting on the forming platform 13 in real time, and adjust the working parameters of the powder feeding and printing part 21 and the multi-axis motion part 20 based on the real-time temperature. In the present invention, the multi-axis motion part 20 cooperates with the telescopic part 22 to realize powder feeding in multiple axis directions, and then lay the powder layer by layer, so that the laid powder is evenly laid. Then, a molten pool is formed by melting the powder in multiple axis directions, improving the uniformity of the molten pool and enhancing the printing quality and printing efficiency.

[0027] See Figures 1 to 12, a moving part 15 is provided at the bottom end of the mounting bracket 10. The moving part 15 includes a mounting base, and moving wheels are provided on the bottom end face of the mounting base. The printing device can be moved to any position through the moving wheels, improving the convenience of moving this device.

[0028] See Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 , the mounting bracket 10 includes a first support rod. The bottom end of the first support plate is fixed on the mounting base. A connecting platform is connected to the top end of the first support rod. An installation frame is installed on the upper end face of the connecting platform. The bottom end face of the forming chamber 11 is fixedly connected above the installation frame. The telescopic part 22 is installed in the installation frame, and the telescopic head of the telescopic part 22 is vertically upward. The telescopic part 22 includes a telescopic rod. In this embodiment, the telescopic rod is an electric telescopic cylinder. An installation groove 110 is provided on the bottom end face of the forming chamber 11. One end of the telescopic rod where the telescopic head is located is connected with an installation table. Multiple jacking rods are connected to the installation table. The multiple jacking rods are all parallel to the telescopic direction of the telescopic rod. The top ends of the multiple jacking rods pass through the installation groove 110 and extend into the forming chamber 11 to be connected with the bottom end face of the forming platform 13 in the forming chamber 11. The forming platform 13 can be lifted in height through the telescopic rod, enabling the device to dynamically adjust the platform position according to printing requirements during the additive printing process, which helps to ensure the uniform deposition of each layer of material, thereby improving the accuracy of the printed part, and further enhancing the printing accuracy, efficiency, flexibility, adaptability, stability and safety of the device; a sealing member 12 is installed in the installation groove 110. Sealing grooves 120 are provided on the sealing member 12 corresponding to the positions of the jacking rods. The jacking rods are sealed by the sealing member 12 in the installation groove 110, increasing the sealing performance of this device; in this embodiment, the sealing member 12 is a rubber film.

[0029] In the present invention, if the telescopic direction of the telescopic part 22 is defined as the movement in the Z-axis direction, the multi-axis movement part 20 is used to realize the movement in the X-axis and Y-axis directions in the forming chamber 11, so that this device can evenly lay metal powder layer by layer in the forming chamber 11 and perform melting scanning. The following provides two installation methods; An installation method of the multi-axis movement part 20 proposed by the present invention, such as Figures 2 to 7As shown, the multi-axis moving part 20 includes a first moving member 200. The moving direction of the first moving member 200 is perpendicular to the moving direction of the telescopic part 22. The first moving member 200 is installed on the inner wall of the forming chamber 11. A first synchronous belt connecting seat 201 is installed on the first moving member 200. A second moving member 202 is installed in the first synchronous belt connecting seat 201. The moving direction of the second moving member 202 is perpendicular to the moving direction of the first moving member 200 and the moving direction of the telescopic part 22 respectively. A powder feeding and printing part 21 is installed on the second moving member 202.

[0030] Exemplarily, the first moving member 200 includes a first servo motor 200-1. The first servo motor 200-1 is vertically installed in the forming chamber 11, that is, the output shaft of the first servo motor 200-1 is vertically downward, and the output shaft is parallel to the telescopic direction of the telescopic part 22. A first pulley 200-2 is connected to the output shaft of the first servo motor 200-1. A second pulley 200-3 is provided at a position on the inner wall of the forming chamber 11 at the same height as the first pulley 200-2. The axes of the first pulley 200-2 and the second pulley 200-3 are parallel to each other, and the second pulley 200-3 and the first servo motor 200-1 are installed on the inner wall on the same side of the forming chamber 11. A first transmission belt 200-4 is connected between the first pulley 200-2 and the second pulley 200-3. Through the first transmission belt 200-4, the first pulley 200-2 and the second pulley 200-3 rotate synchronously. One end of the first synchronous belt connecting seat 201 is connected to the first transmission belt 200-4. A guiding connecting platform is provided on the inner wall of the forming chamber 11 above the first transmission belt 200-4. The guiding connecting platform movably connects the end of the first synchronous belt connecting seat 201 close to the first transmission belt 200-4, so that the first synchronous belt connecting seat 201 is parallel to the forming platform 13 in the forming chamber 11, and can reciprocate between the first pulley 200-2 and the second pulley 200-3 in the forming chamber 11 along with the first transmission belt 200-4, thereby realizing the movement of the powder feeding and printing part 21 in one direction in the X-axis or Y-axis direction; The second moving member 202 includes a first electric slide table 202-1. The first electric slide table 202-1 is installed in the first synchronous belt connecting seat 201. The moving direction on the first electric slide table 202-1 and the moving direction of the first synchronous belt connecting seat 201 under the action of the first transmission belt 200-4 are in the same plane, and the moving directions of the two are perpendicular to each other, thereby realizing the movement of the powder feeding and printing part 21 in the other direction in the X-axis or Y-axis direction; a first printing connecting plate 202-2 is connected to the first electric slide table 202-1. The powder feeding and printing part 21 is vertically installed on one side end face of the first printing connecting plate 202-2. Through the second moving member 202 and the first moving member 200, the powder feeding and printing part 21 can move in the X-axis and Y-axis directions on a fixed horizontal plane in the forming chamber 11, and then cooperate with the telescopic part 22 to realize the movement in multiple axial directions, so that the powder laid layer by layer on the forming platform 13 by the powder feeding and printing part 21 is uniform and the uniformity of the molten pool formed after the powder is melted is unified, improving the uniformity of the material in the printed parts, and thus improving the printing efficiency.

[0031] Another installation method of the multi-axis moving part 20 proposed by the present invention is as Figures 8 to 11 shown. The multi-axis moving part 20 includes a third moving member 203 and a fourth moving member 205. The moving direction of the third moving member 203 is perpendicular to the moving direction of the telescopic part 22, and the moving direction of the fourth moving member 205 is perpendicular to the moving directions of the third moving member 203 and the telescopic part 22 respectively; the third moving member 203 is installed on the inner wall of the forming chamber 11, a second synchronous belt connecting seat 204 is installed on the third moving member 203, and the powder feeding and printing part 21 is installed on the second synchronous belt connecting seat 204; the fourth moving member 205 is installed above the forming platform 13.

[0032] Exemplarily, the third moving member 203 includes a second servo motor 203-1. The second servo motor 203-1 is installed in the forming chamber 11, that is, the output shaft of the second servo motor 203-1 is vertically downward, and the output shaft is parallel to the telescopic direction of the telescopic portion 22. A third pulley 203-2 is connected to the output shaft of the second servo motor 203-1. A fourth pulley 203-3 is provided at a position on the inner wall of the forming chamber 11 at the same height as the third pulley 203-2. The axial directions of the third pulley 203-2 and the fourth pulley 203-3 are parallel to each other, and the third pulley 203-2 and the fourth pulley 203-3 are installed on the inner wall of the same side in the forming chamber 11. A second transmission belt 203-4 is connected between the third pulley 203-2 and the fourth pulley 203-3. The second transmission belt 203-4 enables the third pulley 203-2 and the fourth pulley 203-3 to rotate synchronously. One end of the second synchronous belt connecting seat 204 is connected to the second transmission belt 203-4; the guiding connection platform is provided at a position on the inner wall of the forming chamber 11 above the second transmission belt 203-4. The third pulley 203-2 enables the second synchronous belt connecting seat 204 to reciprocate between the third pulley 203-2 and the fourth pulley 203-3. The guiding connection platform movably connects one end of the second synchronous belt connecting seat 204 close to the first transmission belt 200-4. A powder feeding and printing portion 21 is vertically installed on one side end face of the second synchronous belt connecting seat 204, thereby realizing the movement of the powder feeding and printing portion 21 in one direction in the X-axis or Y-axis direction; The fourth moving member 205 includes a second electric slide table 205-1. The second electric slide table 205-1 is installed above the forming platform 13, and the moving direction on the second electric slide table 205-1 is perpendicular to the moving direction of the second synchronous belt connecting seat 204 under the action of the third pulley 203-2, thereby realizing the movement of the powder feeding and printing portion 21 in the other direction in the X-axis or Y-axis direction. A printing platform 205-2 is installed above the second electric slide table 205-1. The third moving member 203 enables the powder feeding and printing portion 21 to move along one direction, and the fourth moving member 205 enables the platform for laying powder to move along the other direction. Then, in cooperation with the telescopic portion 22, the multi-axis movement is realized, so that the powder laid layer by layer by the powder feeding and printing portion 21 on the forming platform 13 is uniform and the uniformity of the molten pool formed after the powder is melted is unified, improving the uniformity of the materials in the printed parts, and further improving the printing efficiency.

[0033] Such as Figure 6 、 Figure 7 、 Figure 10 and Figure 11As shown in the figure, the powder feeding and printing unit 21 includes an energy beam printing head 210. The energy source for the energy beam printing head 210 mainly includes a laser or an electron beam emitter. High-power lasers are used in laser powder bed melting, while electron beam melting utilizes an electron beam to rapidly melt metal powder. The beam of the energy source is projected onto the laid metal powder layer through focusing and a controller, providing sufficient energy to melt it. Different types of energy sources are suitable for different materials and manufacturing requirements. Laser melting is suitable for high-precision parts, while electron beam melting is suitable for large-size and thick-layer forming. The energy beam printing head 210 is installed on the multi-axis motion unit 20, and the lower end of the energy beam printing head 210 is located directly above the forming platform 13. An annular powder feeder 211 is provided at the lower end of the energy beam printing head 210. A powder delivery pipe 14 is provided at the top of the annular powder feeder 211. The powder delivery pipe 14 is externally connected to a powder conveyor through a pipeline. The powder conveyor is mainly responsible for precisely delivering the powder materials of metal or other materials into the annular powder feeder 211. Usually, the powder conveyor includes a powder storage cylinder and a conveyor. The powder storage cylinder stores the powder materials for additive manufacturing, and the conveyor transports the powder materials stored in the powder storage cylinder into the annular powder feeder 211 in the forming chamber 11.

[0034] As Figure 12 shown, an adsorber 24 is provided at a position near the top of the energy beam printing head 210. The adsorber 24 is communicatively connected to a dust concentration sensor, and the dust concentration sensor is installed in the forming chamber 11. The powder concentration dissipated in the forming chamber 11 is detected by the dust concentration sensor. When the powder concentration exceeds the preset concentration threshold, a signal is sent to the adsorber 24, and the power of the adsorber 24 is adjusted according to the concentration range. The powder materials dissipated in the forming chamber 11 are absorbed by the adsorber 24. The higher the concentration, the higher the power of the adsorber 24, and the lower the concentration, the lower the power of the adsorption part 24. The adsorber 24 moves along with the energy beam printing head 210 to improve the adsorption effect and adsorption range, and prevent the excessive adsorption force at some positions from affecting the uniformity of the laid powder materials. A dust storage container is provided at the top of the adsorber 24, and the powder materials absorbed by the adsorber 24 are recovered through the dust storage container. A one-way valve is provided at the connection between the adsorber 24 and the dust storage container to prevent the powder materials recovered in the dust storage container from flowing back into the adsorber 24. Among them, the adsorber 24 is one of an electromagnetic adsorber or a vacuum cleaner.

[0035] In the present invention, the monitoring system includes an oxygen sensor 23, a closed-loop temperature control module, and a detection and adjustment module. Among them, the oxygen sensor 23 is installed on the forming chamber 11 for detecting the oxygen concentration in the forming chamber 11. By real-time monitoring the oxygen concentration in the forming chamber 11, it is ensured that the oxygen content in the forming chamber 11 is controlled at an extremely low level, avoiding the concentration exceeding the set threshold and causing the metal powder in the forming chamber 11 to oxidize, which affects the forming quality of the three-dimensional object. The closed-loop temperature control module includes a temperature sensor and a controller. The controller is communicatively connected to the temperature sensor and the powder feeding and printing unit 21. Among them, the temperature sensor is used to collect the temperature of the molten pool formed after the powder is melted. The controller controls the laser or electron beam power for melting the powder input on the powder feeding and printing unit 21 by obtaining the temperature data collected by the temperature sensor, so as to prevent the temperature of the molten pool from being higher or lower than the preset threshold, which affects the quality of three-dimensional object forming. The detection and adjustment module includes a detector and a regulator. The regulator is communicatively connected to the detector, the powder feeding and printing unit 21, and the multi-axis movement unit 20. The detector is used for the uniformity of the molten pool formed after the powder is melted. The regulator is used to control the powder feeding rate of the powder feeding and printing unit 21 and the moving speed of the multi-axis movement unit 20 by obtaining the uniformity collected by the detector. In the invention, in the real-time regulation, the regulator and the controller introduce the existing integral and differential control (that is, both the regulator and the controller adopt a PID controller), so as to ensure in real time that the molten pool is within the set optimal temperature range, prevent temperature fluctuations, improve the uniformity of the molten pool formed after each layer of powder is melted, and further improve the stability of the additive manufacturing process and the final quality of three-dimensional object forming.

[0036] Among them, the detector in the detection and adjustment module is a camera or a laser scanner. The regulator determines the contour and size of the molten pool formed after the powder is melted through image processing technologies such as edge detection and region segmentation, and compares the actual shape of the molten pool with the preset standard shape: The specific comparison process is as follows:

[0037] Among them, is the standard molten pool area, is the actual molten pool area, is the uniformity of the molten pool shape, The closer it is to 1, the better the uniformity of the molten pool. When it is detected that the molten pool is uneven, the powder feeding rate F is adjusted through feedback control to maintain uniformity; The specific process is as follows:

[0038] Among them, and are adjustment coefficients, which are used to control the response of the powder feeding rate to the non-uniformity, is the powder feeding rate adjustment amount, and are the non-uniformity degrees of the shape and temperature; when the non-uniformity degree of the molten pool shape or temperature is large, the powder feeding rate is increased or decreased: , thereby improving the uniformity of the molten pool.

[0039] When adjusting the melting parameters, the energy beam power P is related to the scanning speed V. If the energy beam power is too large or too small, it will cause uneven temperature distribution, and if the speed is too fast or too slow, it will affect the shape of the molten pool. Calculate the laser power adjustment amount ∆P and the scanning speed adjustment amount ∆V according to the uniformity parameter, that is , , where and are the power and speed adjustment coefficients; when the temperature uniformity is low, reduce the energy beam power, that is , when the shape uniformity is low, appropriately reduce the scanning speed to improve the uniformity of the molten pool.

[0040] The monitoring system also includes a management module. The management module is responsible for coordinating the operation of each component, slicing the three-dimensional model into multiple two-dimensional planes, and directing each component to print layer by layer. In the present invention, the monitoring system ensures the stability and high precision of the entire printing process by adjusting parameters such as the position of the moving part, powder flow rate, laser or electron beam power, frequency, etc. In addition, the monitoring system usually cooperates with sensors to monitor parameters such as temperature, stress, and molten pool state during the printing process in real time, so as to make timely adjustments to abnormal situations.

[0041] The present invention also proposes a multi-axis motion 3D printing method, which is applied to the above-mentioned multi-axis motion 3D printing device, and includes the following steps: Transport powder materials to the powder feeding and printing part 21 in the forming chamber 11 based on the powder delivery amount set according to the manufacturing parameters; Drive the multi-axis moving part 20 to drive the powder feeding and printing part 21 to move above the forming platform 13 based on the powder material trajectory set according to the manufacturing parameters, and lay the powder materials layer by layer; perform the first melting scan on the powder materials laid layer by layer based on the preset first preset trajectory, and perform the second melting scan on the powder materials laid layer by layer according to the preset second preset trajectory to obtain the finally formed three-dimensional object; wherein, the monitoring system real-time detects the real-time temperature and real-time uniformity after the powder materials on the forming platform 13 are melted, and adjusts the working parameters of the powder feeding and printing part 21 and the multi-axis moving part 20 based on the real-time temperature.

[0042] Specifically, transport the powder materials to the annular powder feeder 211 according to the powder delivery amount set according to the manufacturing parameters, and then transport the powder materials to the forming platform 13 in the forming chamber 11 according to the set powder feeding trajectory. The powder delivery amount is preset according to the current scanning layer of the current energy beam print head 210. When the annular powder feeder 211 transports the powder materials to the forming platform 13 in the forming chamber 11 according to the set powder feeding trajectory, its powder feeding trajectory is also preset according to the current scanning layer of the current energy beam print head 210.

[0043] In this embodiment, the process of setting the powder feeding trajectory includes: Based on the forming data of the actual three-dimensional object, different layer thicknesses are set for each region, and the layer thickness of each layer is determined according to the complexity of the region, surface curvature, and detail requirements; specifically, the layer thickness of different regions affects the powder delivery amount. A thinner region requires less powder material, while a thicker region requires more powder material; calculate the relationship between the powder supply amount and the layer thickness. Assuming the density of the powder material is , and the width of the trajectory path is W, then the powder demand of a certain region can be calculated by a formula; The calculation formula is: ; Among them, is the layer thickness of this region, is the length of the trajectory path, W is the width of the trajectory path, is the density of the powder material. The powder demand on each trajectory path is updated in real time through this formula, and the powder delivery amount varies with the characteristics of the trajectory path.

[0044] During the execution of the feeding trajectory, the opening and closing rate of the supply system is adjusted in real time to make the powder delivery amount consistent with the demand of the trajectory path, avoiding overage or shortage; The adjustment formula is:

[0045] Among them, is the path completion time, is the moving speed of the energy beam print head 210, is the length of the trajectory path, W is the width of the trajectory path, is the density of the powder material, is the layer thickness of this region.

[0046] When generating the first preset trajectory and the second preset trajectory, use a path planning algorithm based on graph search, such as the Adaptive A* or D Lite* path planning algorithm. Adaptive A* will reuse the previously calculated information each time the path is updated to accelerate the search speed; D* Lite realizes dynamic adjustment through incremental updates of the path tree and is suitable for real-time changing environments; The specific implementation steps are as follows: Define the forming area as a three-dimensional grid graph GVE, where V represents grid nodes, E represents the reachable paths between nodes, set the starting node s as the current print head position, and the ending node g as the printing end point planned for the current layer; use the heuristic function to estimate the distance from the current node n to the ending node g, and use the Euclidean distance for estimation: The specific process is:

[0047] Among them, is the three-dimensional coordinate of node n, is the three-dimensional coordinate of the end point g; Furthermore, a total path cost function is set: , where is the cumulative path cost from the start point s to the current node n, is the heuristic estimate from the current node n to the end point g; Each time, select the node with the smallest from the unvisited nodes for expansion to ensure the optimal path.

[0048] Furthermore, path intersection detection is performed. The specific process is as follows: Define the path sets of adjacent layers , When planning the path, check whether each path intersects with the completed paths; The intersection degree can be calculated as follows:

[0049] where is the coordinate of path P i at node k, is the indicator function; If , then δ = 1, otherwise δ = 0; If is greater than the set threshold, it means there are many path intersections. Re-select the path or avoid intersections by appropriately adjusting the path position.

[0050] Furthermore, idling detection is performed. The specific process is as follows: Define the idling cost as the cost caused by idling in path planning: , where is the length of the k-th path segment, is the idling speed value; The optimization goal is to minimize to ensure the least overlap of path segments and the shortest idling segments.

[0051] Furthermore, when planning the scanning trajectory, an optimal angle coverage strategy is set. The specific process is as follows: To ensure the optimal coverage of complex areas, select an optimal tilt angle θ and azimuth angle ϕ to maximize the coverage of the printing layer; Assume r is the normal vector of the printing surface. The required tilt angle θ is calculated by the following formula:

[0052] where d is the multi-axis movement direction, is the dot product of the normal vector and the movement direction; By adjusting 𝜃 to make the movement direction of each scanning layer consistent with the printing direction, the error caused by the tilt angle can be reduced and the printing quality can be improved; In high-complexity areas, a delay-priority strategy is introduced, that is, simple areas are skipped first in path planning, and complex parts are printed intensively; And the specific formula is:

[0053] where is the path cost, is the path complexity, is the weight for preferring complex areas.

[0054] After one layer of scanning is completed, the telescopic part 22 drives the forming platform 13 to descend by the distance of the next layer, and the above scanning process is repeated, and so on until the finally formed three-dimensional object is obtained.

[0055] In this embodiment, when melting and scanning the powder material, the printing method further includes: Real-time collecting the temperature of the molten pool formed after the powder material melts and adjusting the temperature of the molten pool in real time to avoid the temperature of the molten pool being higher or lower than the preset threshold.

[0056] Specifically, a closed-loop temperature control module and a detection and adjustment module are installed in the forming chamber 11, the multi-axis movement part 20 or the powder feeding and printing part 21. When melting and scanning the powder material, the temperature of the molten pool area is collected in real time. To ensure real-time performance, the data collection frequency needs to reach the millisecond level or higher to capture the minute fluctuations of the molten pool temperature in a timely manner; the optimal temperature range of the molten pool is set according to factors such as material properties, layer thickness, and printing speed to avoid poor sintering of the material (low temperature) or over-melting (high temperature) caused by temperature differences, resulting in uneven forming; the temperature of the molten pool monitored in real time is compared with the optimal temperature threshold. If the temperature of the molten pool is greater than the optimal temperature threshold, the laser or electron beam power is appropriately reduced to reduce the heating intensity of the molten pool. If the temperature of the molten pool is less than the optimal temperature threshold, the laser or electron beam power is increased to enhance the heating of the molten pool; the adjustment value of the laser or electron beam power is proportional to the temperature deviation, and proportional-integral-derivative control is used.

[0057] Furthermore, if the laser or electron beam power is already close to the equipment limit but the temperature is still unstable, the temperature can be controlled by adjusting the scanning speed of the energy beam print head 210; that is, if the temperature of the molten pool is greater than the optimal temperature threshold, the scanning speed is increased to reduce the heating time of the molten pool area. If the temperature of the molten pool is less than the optimal temperature threshold, the scanning speed is reduced to increase the heating time of the molten pool area.

[0058] After each adjustment, the molten pool temperature is recollected, and the above process is continuously executed to form a feedback control loop to ensure that the molten pool temperature is always near the target temperature.

[0059] The foregoing has shown and described the basic principles, main features and advantages of the present invention. For a person skilled in the art, it is obvious that the present invention is not limited to the details of the above-described exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present invention. Any reference signs in the claims should not be construed as limiting the claims involved.

[0060] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative manner of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only to illustrate the technical idea of the present invention, and the protection scope of the present invention cannot be limited thereby. Any modification made on the basis of the technical solution according to the technical idea proposed by the present invention falls within the protection scope of the claims of the present invention.

Claims

1. A multi-axis motion 3D printing device, characterized in that: It comprises a mounting bracket (10), a forming chamber (11) being mounted on the top of the mounting bracket (10), a multi-axis motion part (20) being mounted in the forming chamber (11), and a powder feeding printing part (21) being mounted on the multi-axis motion part (20); A forming platform (13) is provided on the bottom end surface of the forming chamber (11) at a position corresponding to the powder feeding printing part (21), and a telescopic part (22) is installed at the bottom of the forming platform (13), and the telescopic part (22) is installed in the mounting bracket (10); The forming bin (11) is provided with a monitoring system, the monitoring system being communicatively connected to the powder feeding and printing section (21) and the multi-axis motion section (20), the monitoring system being used to detect in real time the real-time temperature and real-time uniformity of the powder material after melting on the forming platform (13), and adjusting the working parameters of the powder feeding and printing section (21) and the multi-axis motion section (20) based on the real-time temperature.

2. A multi-axis motion 3D printing device according to claim 1, characterized in that: The multi-axis motion part (20) comprises a first moving member (200), the moving direction of the first moving member (200) is perpendicular to the moving direction of the telescopic part (22), the first moving member (200) is mounted on the inner wall of the forming chamber (11), a first synchronous belt connecting seat (201) is mounted on the first moving member (200), a second moving member (202) is mounted in the first synchronous belt connecting seat (201), and the moving directions of the second moving member (202) are perpendicular to the moving directions of the first moving member (200) and the telescopic part (22), respectively; The powder feeding printing unit (21) is mounted on the second movable member (202).

3. A multi-axis motion 3D printing device according to claim 2, characterized in that: The first moving member (200) comprises a first servo motor (200-1), the first servo motor (200-1) being installed in the forming bin (11), a first pulley (200-2) being connected to an output shaft of the first servo motor (200-1), a second pulley (200-3) being arranged at the same height as the first pulley (200-2) in the forming bin (11), a first transmission belt (200-4) being connected between the first pulley (200-2) and the second pulley (200-3), and one end of the first transmission belt (200-4) being connected to the first synchronous belt connecting seat (201); The second movable member (202) comprises a first electric slide (202-1), the first electric slide (202-1) being installed in the first synchronous belt connecting seat (201), the first electric slide (202-1) being connected to a first printing connecting plate (202-2), and the powder feeding printing unit (21) being installed on the first printing connecting plate (202-2).

4. The multi-axis motion 3D printing device according to claim 1, characterized in that: The multi-axis motion part (20) comprises a third moving member (203) and a fourth moving member (205); the moving direction of the third moving member (203) is perpendicular to the moving direction of the telescopic part (22); and the moving direction of the fourth moving member (205) is perpendicular to the moving direction of the third moving member (203) and the moving direction of the telescopic part (22); The third moving member (203) is mounted on the inner wall of the forming chamber (11), a second synchronous belt connecting seat (204) is mounted on the third moving member (203), and the powder feeding printing unit (21) is mounted on the second synchronous belt connecting seat (204); The fourth moving member (205) is installed above the forming platform (13).

5. The multi-axis motion 3D printing device according to claim 4, characterized in that: The third moving member (203) comprises a second servo motor (203-1), the second servo motor (203-1) is installed in the forming bin (11), a third pulley (203-2) is connected to the output shaft of the second servo motor (203-1), a fourth pulley (203-3) is arranged at the same height as the third pulley (203-2) in the forming bin (11), a second transmission belt (203-4) is connected between the third pulley (203-2) and the fourth pulley (203-3), and one end of the second transmission belt (203-4) is connected to the second synchronous belt connecting seat (204); The fourth movable member (205) comprises a second electric slide (205-1), the second electric slide (205-1) being installed above the forming platform (13), and a printing platform (205-2) being installed on the second electric slide (205-1).

6. The multi-axis motion 3D printing device according to claim 1, characterized in that: The telescopic portion (22) comprises a telescopic rod, and a mounting groove (110) is provided on the bottom end surface of the forming bin (11). The mounting groove (110) is provided at one end of the telescopic rod located at the telescopic head and is connected to the forming platform (13) in the forming bin (11); A sealing member (12) is installed in the installation groove (110), a sealing groove (120) is provided on the sealing member (12), and one end of the telescopic rod located at the telescopic head passes through the sealing groove (120); The other end of the telescopic rod is fixed on the mounting bracket (10).

7. The multi-axis motion 3D printing device according to claim 1, characterized in that: The powder feeding printing section (21) comprises an energy beam printing head (210), the energy beam printing head (210) being mounted on the multi-axis motion section (20), an annular powder feeder (211) being arranged on the lower end of the energy beam printing head (210), a powder material conveying pipe (14) being arranged on the top of the annular powder feeder (211), and the powder material conveying pipe (14) being externally connected to the powder material conveyor via a pipeline.

8. The multi-axis motion 3D printing device according to claim 7, characterized in that: An adsorber (24) is provided on the energy beam print head (210) near the top thereof, the adsorber (24) being communicatively connected to a dust concentration sensor, the dust concentration sensor being installed in the forming chamber (11); The dust concentration sensor is used to detect the dust concentration in the forming bin (11), and based on the dust concentration, control the adsorber (24) to absorb the powder material overflowing from the forming bin (11); Wherein, the adsorber (24) is an electromagnetic adsorber or a vacuum cleaner.

9. The multi-axis motion 3D printing device according to claim 1, characterized in that: The monitoring system comprises an oxygen sensor (23), a closed-loop temperature control module and a detection and adjustment module; The oxygen sensor (23) is mounted on the forming chamber (11) and is used to detect the concentration of oxygen in the forming chamber (11); The closed-loop temperature control module comprises a temperature sensor and a controller, wherein the controller is communicatively connected to the temperature sensor and the powder feeding printing unit (21); Wherein, the temperature sensor is used to collect the temperature of the molten pool formed after the powder is melted; The controller is used to control the laser or electron beam power input to the powder feeding printing part (21) for melting the powder by acquiring the temperature data collected by the temperature sensor; The detection and adjustment module comprises a detector and a regulator, wherein the regulator is communicatively connected to the detector, the powder feeding printing part (21) and the multi-axis motion part (20); Wherein, the detector is used to measure the uniformity of the molten pool formed after the powder is melted; The controller is used to control the powder feeding rate of the powder feeding printing part (21) and the moving speed of the multi-axis motion part (20) by acquiring the uniformity collected by the detector.

10. A multi-axis motion 3D printing method, applied to a multi-axis motion 3D printing device according to any one of claims 1 to 9, characterized in that: The following steps are involved: Delivering powder to a powder delivery printing section (21) in a forming bin (11) based on a powder delivery amount set by manufacturing parameters; The powder material trajectory driven multi-axis motion unit (20) based on the manufacturing parameter setting drives the powder feeding and printing unit (21) to move above the forming platform (13) to lay the powder material layer by layer; A first melting scan is performed on the powder material laid layer by layer based on a preset first preset trajectory, and a second melting scan is performed on the powder material laid layer by layer based on a preset second preset trajectory to obtain a final formed three-dimensional object; wherein the monitoring system detects in real time the real-time temperature and real-time uniformity of the powder material on the forming platform (13) after melting, and adjusts the working parameters of the powder feeding and printing part (21) and the multi-axis motion part (20) based on the real-time temperature.

Images