Rail-free guidance system for 3D printing

Abstract

The present invention discloses a non-fixed rail guidance system for 3D printing. The system is characterized by comprising multiple positioning points disposed on the surface of a printing platform, each of which is provided with a positioning guide member. The positioning points are arranged in an array to form a two-dimensional guiding point cloud array. The guidance system also includes an automated guided vehicle (AGV) equipped with a point cloud detection sensor capable of sensing and locating the positioning guide members at each of the positioning points. A universal wheel system is also provided below the AGV and connected to a drive motor capable of driving the universal wheel system for steering. A forming cylinder device for 3D printing is mounted on the AGV. This device offers the advantages of flexible and variable control, better interference avoidance, and a wider range of printing sequence possibilities.

Description

[0001] This application is a divisional application of the patent application number 202111096579.2, "A Multi-station 3D Printer" with application date 2021-9-18. Technical Field

[0002] The present invention relates to a 3D printer, and in particular to a non-fixed guide rail type guiding system for 3D printing. Background Art

[0003] 3D printing is a type of rapid prototyping technology, also known as additive manufacturing. It uses lasers, hot melt nozzles, and other methods to build objects by gradually stacking and bonding materials such as plastic, metal, and ceramic powders based on digital models. In recent years, 3D printing has been widely used in a wide range of fields, including industrial design, jewelry, automotive, aerospace, dentistry, healthcare, and education.

[0004] Currently, common 3D printers include selective laser melting (SLM), selective laser sintering (SLS), 3D powder bonding, and fused deposition modeling (FDM). 3D powder bonding printing, also known as 3DP, is similar to SLS in that it uses powder materials, such as ceramic powder or metal powder, to create a part. The difference is that the powders are not bonded together through sintering. Instead, the printhead uses an adhesive (such as silicone) to "print" the part's cross-section onto the powder. Adhesive-bonded parts have lower strength and require post-processing. The specific process is as follows: After the previous layer is bonded, the build cylinder descends by the build layer thickness (usually 0.013-0.1mm). The powder supply cylinder pushes out a certain amount of powder, which is then flattened by the powder roller into the build cylinder. Under computer control, the printhead selectively sprays the binder to build layers according to the build data for the next build section. This cycle of powder feeding, powder spreading, and binder spraying is repeated, ultimately completing the 3D powder bonded print. The areas not sprayed with binder are dry powder, which plays a supporting role during the forming process and is removed after the forming is completed.

[0005] With advancements in manufacturing, many products require different materials for different parts to achieve varying performance. However, mainstream 3D printers currently on the market are generally limited to printing objects using a single material, resulting in significant limitations for 3D printers. They are unable to print parts composed of two or even multiple materials simultaneously. This is also true for 3DP processes.

[0006] CN105196549B previously disclosed a parallel multi-station 3D printer. This invention proposes a novel parallel multi-station 3D printer suitable for rapid prototyping technology, comprising a computer, a bracket, a 3D printer assembly, and a conveyor belt system. The 3D printer assembly is a 3D printer that places multiple stations side by side as needed, with the computer controlling printing tasks to achieve parallel assembly line printing.

[0007] The printer of the above-mentioned existing patent has the following inconveniences. 1 Although it is possible to print multiple materials in one product, it uses a fixed printing assembly line guide for guidance, which has the defects of complex assembly line guide structure, inconvenient control and scheduling, and poor flexibility. 2 When spreading powder before printing each layer, a conventional powder spreading roller device and a powder cylinder are used to complete the powder spreading, which has the defects of complex structure, slow speed, easy ripples on the surface after spreading the powder, and low flatness. 3 The specific printing process adopts the classic printing mode, that is, each time a layer of powder is spread, the print head is used to print along the contour of the product layer, and the product is obtained by printing layer by layer. In this way, due to the limitation of the effect of the printing adhesive, the thickness of each layer of powder cannot be too thick, and each layer of powder is printed once by the print head, which makes the printing efficiency low; if the thickness of each layer of powder is increased to improve the printing efficiency, it will lead to a decrease in printing quality and accuracy, so printing efficiency and quality accuracy cannot be achieved at the same time. Summary of the Invention

[0008] In response to the shortcomings of the aforementioned prior art, the present invention aims to solve the following technical problem: How to provide a multi-station 3D printer that can conveniently print different materials in a single product, with a simple structure and flexible and convenient control? Furthermore, it can improve the accuracy and convenience of powder spreading, thereby enhancing printing efficiency and quality. The present invention also provides a non-fixed rail-type guidance system for 3D printing, which offers the advantages of flexible and variable control, better interference avoidance, and a wider range of printing sequence possibilities.

[0009] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0010] A multi-station 3D printer includes a horizontally arranged printing platform with multiple printing stations arranged on the printing platform. Each printing station is fixedly equipped with a set of printing devices. It also includes a forming cylinder device and a guiding system. The guiding system is used to guide the docking of the forming cylinder device and the printing device; it is characterized in that the guiding system is a non-fixed guide rail type guiding system, and the non-fixed guide rail type guiding system can generate a guiding path as needed.

[0011] In this way, the fixed guide rail is eliminated and instead generated according to needs, making the control more flexible and convenient.

[0012] Furthermore, the non-fixed rail guidance system includes a plurality of positioning points arranged on the surface of the printing platform, and a positioning guide component is provided at each positioning point. The positioning points are arranged in an array to form a two-dimensional guidance point cloud array; the guidance system also includes an automatic guided vehicle, and the automatic guided vehicle is provided with a point cloud detection sensor that can sense and locate the positioning guide components at each positioning point. A universal wheel system is also provided under the automatic guided vehicle and is connected to a drive motor, and the drive motor can drive the universal wheel system to turn and travel; the forming cylinder device is installed on the automatic guided vehicle.

[0013] In this way, when this equipment is in use, it can rely on point cloud detection sensors to detect the position of positioning guide components at various positioning points, control the AGV to move forward between different positioning points, and rely on the two-dimensional guidance point cloud array to control the planning and generation of the driving path, so that the forming cylinder device can follow the AGV on the printing platform and complete the docking between different printing devices, thereby realizing the printing of different materials in different parts of a product to meet the performance requirements of different parts. At the same time, it has the advantages of flexible and changeable control, better ability to avoid interference, and realize more printing sequence possibilities; the number of printing stations and AGVs can be arranged according to actual production needs.

[0014] Furthermore, the positioning guide component is an electromagnetic generator, and the point cloud detection sensor is a magnetic navigation sensor.

[0015] In this way, the electromagnetic generators can be turned on and off by a computer or other control device. During use, the electromagnetic generators along the desired driving path are turned on, and the electromagnetic generators along the driving path are connected in series, creating an effect similar to a guiding magnetic strip. At the same time, the remaining electromagnetic generators are turned off, and the magnetic navigation sensor is used to guide the AGV along the path. This allows for the generation of different driving paths based on the needs of the corresponding AGV, better avoiding interference from other AGVs. This allows multiple printing stations and a large number of AGVs to be deployed on the printing platform, allowing more AGVs to work together on the same printing platform and participate in printing, greatly improving efficiency. At the same time, the driving path blocks interference from other positioning points, greatly improving the reliability and stability of the driving path.

[0016] Furthermore, the positioning guide component is buried below the upper surface of the printing platform.

[0017] This improves protection and extends lifespan.

[0018] Furthermore, each positioning point includes at least one wireless charging position, a wireless charging device is buried under the wireless charging position, and a wireless charging coil is correspondingly provided in the middle of the lower surface of the automatic guided vehicle. The wireless charging coil is connected to the battery installed on the automatic guided vehicle, and the battery is connected to the drive motor.

[0019] In this way, the automatic charging and driving endurance of the automatic guided vehicle can be achieved, making it more convenient to control the movement sequence and path of the automatic guided vehicle.

[0020] Furthermore, at least part of the wireless charging positions are located at the printing positions on the printing platform.

[0021] In this way, it is convenient for the automatic guided vehicle to drive into the printing station and charge while waiting for printing, so that the charging process does not occupy working time.

[0022] Furthermore, the automatic guided vehicle is also provided with a wireless communication control module, which is connected to the drive motor to realize control.

[0023] In this way, it is convenient to control the automatic guided vehicle to move along the planned path through wireless communication with a computer or other control device at a distance.

[0024] Furthermore, a positioning sensor is provided on the automatic guided vehicle or the printing station, and a positioning sensor detection component is correspondingly provided on the printing station or the automatic guided vehicle.

[0025] In this way, when the automatic guided vehicle arrives at the printing station, it can rely on the coordinated detection between the positioning sensor and the positioning sensor detection component to achieve accurate positioning of the automatic guided vehicle, better ensure that the forming cylinder device on the automatic guided vehicle and the printing device on the printing station can be accurately docked, and ensure printing quality.

[0026] Furthermore, the positioning sensor preferably adopts a contact switch, and the positioning sensor detection component adopts a hard component that can cooperate with the contact switch to realize contact detection.

[0027] This has the advantages of simple structure, convenient implementation and reliable use.

[0028] Furthermore, there are two pairs of contact switches which are respectively mounted on contact switch mounting brackets arranged upward on both sides of the automatic guided vehicle, and the positioning sensor detection component is a contact protrusion formed on a pair of mounting brackets corresponding to the printing station.

[0029] In this way, the precise positioning of the automatic guided vehicle at the printing station can be more conveniently achieved.

[0030] Furthermore, the universal wheel system includes four Mecanum wheels installed at the four corners below the automatic guided vehicle, and each Mecanum wheel is connected to a corresponding drive motor.

[0031] In this way, the drive motor drives the four Mecanum wheels to rotate at different speeds, which can make the AGV move in different directions, so the steering of the AGV can be better controlled.

[0032] Furthermore, the automatic guided vehicle includes a horizontally arranged base plate, the Mecanum wheels and the corresponding drive motors are installed below the base plate, the forming cylinder device is installed above the middle of the base plate, the point cloud detection sensor is installed below the base plate, the wireless charging coil is installed below the base plate, and the wireless communication control module is installed above the base plate.

[0033] In this way, the functions of each component can be more easily realized.

[0034] Furthermore, the forming cylinder device includes a forming cylinder fixedly mounted overhead at a position above the middle of the automatic guided vehicle, the upper end of the forming cylinder has a circle of flange extending horizontally outward to form a printing plane, and the bottom plate tray of the forming cylinder can be slid up and down to fit on the inner wall of the forming cylinder. The forming cylinder device also includes a lifting device installed on the automatic guided vehicle below the forming cylinder, and the telescopic arm of the lifting device is supported upward and connected to the lower surface of the bottom plate tray.

[0035] In this way, the lifting device lifts the base plate tray upward to a position above the inner cavity of the build cylinder, and then begins to spread powder and print. After each layer is printed, the lifting device retracts downward by one layer, and then spreads powder and prints again in the inner cavity of the build cylinder, and then descends layer by layer until printing is completed. Therefore, it has the characteristics of simple structure, easy control, stability and reliability.

[0036] Furthermore, the four corners of the lower end of the forming cylinder are provided with downward supporting columns, and the positions below the flanges around the upper end of the forming cylinder are also provided with supporting frames arranged obliquely outward and downward.

[0037] In this way, the stability of the forming cylinder can be better guaranteed.

[0038] Furthermore, a waste holding tank is provided on the printing plane at the front end of the forming cylinder.

[0039] In this way, the waste generated during paving can fall down, which can better assist in paving.

[0040] Furthermore, the printing station is formed by multiple pairs of mounting brackets installed in pairs at intervals on one side of the printing platform. The mounting bracket is generally in the shape of an inverted L-shaped arm, and the front end of the arm extends horizontally forward in a direction away from the edge of the printing platform. The printing device is fixed on the mounting bracket.

[0041] In this way, the installation of the printing device is more convenient, and the docking of the forming cylinder device and the printing device is more convenient.

[0042] Furthermore, the printing device includes a Y-axis guide rail installed on the upper end arm of the mounting bracket along the length direction of the arm, an X-axis guide rail is vertically arranged between the two Y-axis guide rails along the horizontal direction, both ends of the X-axis guide rail are slidably engaged on the Y-axis guide rail, and a Y-axis motion control mechanism is provided for controlling the sliding of the X-axis guide rail on the Y-axis guide rail. A print head bracket is slidably mounted on the X-axis guide rail and an X-axis motion control mechanism is provided for controlling the sliding of the print head bracket on the X-axis guide rail. A print nozzle is installed on the print head bracket; the printing device also includes a powder supply mechanism installed above the rear end position of the mounting bracket, and also includes a powder spreading mechanism.

[0043] This makes it easier to control the X and Y motion of the print head.

[0044] Furthermore, the Y-axis motion control mechanism is a Y-axis electric slide, the guide rail of the Y-axis electric slide constitutes a Y-axis guide rail on one side, the slide of the Y-axis electric slide and one end of the X-axis guide rail are fixed, and the Y-axis guide rail on the other side is a linear guide rail, and the other end of the X-axis guide rail can be slidably engaged on the linear guide rail.

[0045] In this way, it has the advantages of simple structure, convenient control and reliable control accuracy.

[0046] Furthermore, the X-axis motion control mechanism is an X-axis electric slide, the guide rail of the X-axis electric slide forms an X-axis guide rail, and the print head bracket is installed on the slide of the X-axis electric slide.

[0047] In this way, it has the advantages of simple structure, convenient control and reliable control accuracy.

[0048] Furthermore, the powder supply mechanism includes a powder box, a discharge port is provided at the lower part of the powder box, a quantitative discharge mechanism is provided at the discharge port, and a discharge shuttle groove extending forward and downward is connected below the quantitative discharge mechanism, and the groove at the lower end of the discharge shuttle groove is horizontally arranged along the width direction between the two corresponding mounting brackets.

[0049] In this way, it is convenient for the powder supply mechanism to quantitatively discharge powder according to the amount required for each spreading, and it is convenient for the powder to be fed into the powder spreading mechanism.

[0050] Furthermore, the quantitative discharging mechanism includes a metering sleeve horizontally arranged at the discharge port, the discharge port is connected through the metering sleeve up and down, a metering roller is coaxially arranged at the internal axis of the metering sleeve, and rectangular blades extending along the axial direction are evenly distributed on the circumferential outer surface of the metering roller. The length of the rectangular blades is consistent with the length of the inner cavity of the metering sleeve, and the outer surface and the inner cavity wall of the metering sleeve are rotatably fitted together. One end of the metering roller can rotatably pass through the end of the metering sleeve and is connected to a metering servo motor.

[0051] In this way, the metering servo motor can be used to control the rotation of the metering roller. Each time it rotates a fixed angle, the cavity between the two blades can be used to scrape a fixed volume of powder downward to ensure uniform quantitative powder supply.

[0052] Furthermore, both ends of the powder box are fixed on the side surfaces of a vertically arranged powder box mounting plate, the lower end of the powder box mounting plate is fixed to the mounting bracket, and the metering servo motor is fixed on the other side surface of the powder box mounting plate.

[0053] This makes it easier to install and fix the powder supply mechanism.

[0054] Furthermore, the powder spreading mechanism includes a powder holding trough horizontally arranged along the width direction between two corresponding mounting brackets. The two ends of the powder holding trough are suspended and fixed below the X-axis guide rail near the two ends through upward connecting plates. The powder holding trough is arranged to be through-connected from top to bottom and has a downwardly arranged scraper on the side of the rear end (the end adjacent to the powder box). The lower end of the scraper has a horizontal blade located at the height of the printing plane. The powder holding trough can accommodate at least one layer of powder required for printing at a time. When the X-axis guide rail slides to the rear end of the Y-axis guide rail, the upper end of the powder holding trough can be docked with the lower end notch of the discharge shuttle trough.

[0055] In this way, when spreading powder, the powder holding trough follows the X-axis guide rail and slides to the rear end of the Y-axis guide rail. Powder is quantitatively discharged from the quantitative discharging mechanism and falls into the powder holding trough through the discharging shuttle trough. Then, as the X-axis guide rail slides forward along the Y-axis guide rail, the scraper is used to scrape the powder that has fallen into the powder holding trough flat, completing the spreading process. This method of using a scraper for spreading powder is more convenient and the powder surface is smooth. In addition, the spreading mechanism and print head are both integrated on the X-axis guide rail. The print head can follow the spreading mechanism and print immediately during the spreading process. Moreover, each print head can print once during each reciprocating spreading process, improving printing quality and efficiency.

[0056] Furthermore, a front nozzle mounting plate in an L-shape facing forward is installed downwardly on the front side of the print head bracket, and a first print nozzle is installed on the horizontal part structure at the lower end of the front nozzle mounting plate.

[0057] In this way, as the powder spreading device moves forward with the X-axis guide to spread the material, the print head is controlled to spray a layer of binder in front of the X-axis guide according to the contour of the product layer, completing a pre-print. The powder is then laid on top, combined with the binder, and smoothed by the scraper. Then, as the X-axis guide returns, the print head is controlled to print normally again. This achieves a single layer of spreading and two prints, which can improve the strength of the formed product and increase the thickness of each printed layer to improve printing efficiency. At the same time, the overall structure is simpler, and material spreading is convenient, fast, and reliable.

[0058] As a better option, the print head bracket is also provided with a nozzle vertical motion control mechanism for controlling the vertical sliding of the front nozzle mounting plate.

[0059] In this way, the height of the first print head position can be adjusted up and down, so that the position of the print head can be adjusted for both prints during a single material laying process so that it prints close to the upper surface of the powder material, thereby better improving printing accuracy. Specifically, when the first print head moves forward with the X-axis guide to print before laying the material, its position can be adjusted downward so that the first print head is at a position one layer of powder height lower than the scraper, completing the binder jet printing close to the upper surface of the previous layer of powder material, thereby better ensuring the contour accuracy of the product printed in this pass. Then, after the first print head moves backward with the X-axis guide to reset, the first print head is adjusted upward to return to a position horizontal with the scraper to achieve normal printing; after the X-axis guide moves backward and resets to the starting end, the printing of this layer is completed, the bottom plate tray in the forming cylinder drops a layer of powder, and the first print head is controlled to move downward the same distance to print the next layer, and this cycle continues until printing is completed. Therefore, it can better improve the overall product appearance quality, and the structure is relatively simple, which is easy to implement.

[0060] Furthermore, the nozzle vertical motion control mechanism includes a vertical guide rail vertically fixed on one side of the print head bracket, one side of the upper end of the front nozzle mounting plate can be slidably engaged on the vertical guide rail, and a nozzle vertical motion control motor is fixedly provided on the upper end of the vertical guide rail. It also includes a screw rod arranged in parallel with the vertical guide rail. The nozzle vertical motion control motor is connected to the screw rod and can drive the screw rod to rotate. A nut is screwed on the thread on the screw rod, and the nut is relatively fixed to the upper end of the front nozzle mounting plate.

[0061] In this way, the vertical movement of the nozzle is controlled by the motor, which rotates the screw. The vertical guide rail limits the rotation of the nut through the front nozzle mounting plate. The screw-nut transmission pair formed by the screw and nut drives the front nozzle mounting plate to achieve vertical sliding control. This has the characteristics of simple structure, reliable control, stable movement, and high control accuracy.

[0062] As another option, the front nozzle mounting plate is fixed to the front side of the print head bracket; a rear L-shaped rear nozzle mounting plate is also installed on the rear side of the print head bracket, and a second print nozzle is installed on the horizontal part structure at the lower end of the rear nozzle mounting plate. The print head bracket is also provided with a nozzle vertical motion control mechanism for controlling the vertical sliding of the rear nozzle mounting plate.

[0063] In this way, when the X-axis guide rail moves back to the rear end of the Y-axis guide rail to load the material, the vertical motion control mechanism of the nozzle can control the second print nozzle to rise above the height of the discharge shuttle slot to avoid interference. Then, during normal printing, the second print nozzle is controlled to fall back to the printing position, so that the two print nozzles relying on this structure can achieve at least two prints during the process of the material laying mechanism moving forward with the X-axis guide rail to lay the material back and forth. For example, during normal printing, the first print nozzle and the second print nozzle can be set to their original position at the same height level as the scraper. When the material laying device lays the material forward, the second print nozzle at the rear achieves the first print of the layer of powder. After the material laying device completes the back and forth return of the layer of powder, the first print nozzle at the front achieves the second print of the layer of powder. Therefore, laying the material once and printing twice can better improve product quality and efficiency. The contour of the product printed for the second time can also take the area between the contours of the products laid before and after the two times, so as to better improve the connection effect of the contour between the two times of powder laying and better improve product precision. At the same time, because the two prints use different print heads, they can also use different binders with different ratios, making their respective performance more targeted. For example, the first print uses a binder that produces normal 3D printing results, while the second print uses a binder that can better improve the bonding effect between the printed powder layer and the powder layer to be laid. This can better improve the final printing effect and enhance product quality. In addition, for some special products, such as those with a uniform width in the front-to-back direction, this device can even achieve the special effect of printing four times in a single round trip laying process, further improving product quality and production efficiency.

[0064] Furthermore, the nozzle vertical motion control mechanism includes a vertical guide rail vertically fixed on the print head bracket, one side of the upper end of the rear nozzle mounting plate can be slidably engaged on the vertical guide rail, and a nozzle vertical motion control motor is fixedly provided on the upper end of the vertical guide rail. It also includes a screw rod arranged in parallel with the vertical guide rail. The nozzle vertical motion control motor is connected to the screw rod and can drive the screw rod to rotate. A nut is screwed on the thread on the screw rod, and the nut is relatively fixed to the upper end of the rear nozzle mounting plate.

[0065] In this way, the vertical movement of the nozzle is controlled by the motor, which rotates the screw. The vertical guide rail limits the rotation of the nut through the front nozzle mounting plate. The screw-nut transmission pair formed by the screw and nut drives the rear nozzle mounting plate to achieve vertical sliding control. The result is a simple structure, reliable control, stable movement, and high control accuracy.

[0066] To sum up, this device has the advantages of being able to easily print different materials in one product, and has a simple structure, flexible and convenient control, can improve powder laying accuracy and convenience, and can improve printing efficiency and quality accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 FIG. 1 is a schematic structural diagram of the first embodiment of the present invention.

[0068] Figure 2 for Figure 1 Schematic diagram of the structure of a separate printing platform.

[0069] Figure 3 for Figure 1 Schematic diagram of the structure of a separate printing device.

[0070] Figure 4 for Figure 3 Top view of .

[0071] Figure 5 for Figure 1 Schematic diagram of the structure of the separate powder supply mechanism.

[0072] Figure 6 for Figure 5 Side sectional view of .

[0073] Figure 7 for Figure 1 Schematic diagram of the structure of the middle powder spreading mechanism.

[0074] Figure 8 for Figure 7 Side sectional view of .

[0075] Figure 9 for Figure 1 Front view of a single automated guided vehicle.

[0076] Figure 10 for Figure 9 Schematic diagram of the three-dimensional structure.

[0077] Figure 11 Schematic diagram of the structure of the printing device in the second embodiment. DETAILED DESCRIPTION

[0078] The present invention will be further described in detail below with reference to specific embodiments.

[0079] First embodiment: Figure 1-10 As shown, a multi-station 3D printer includes a horizontally arranged printing platform 1, on which multiple printing stations are arranged. Each printing station is fixedly provided with a set of printing devices, and also includes a forming cylinder device and a guiding system. The guiding system is used to guide the docking of the forming cylinder device and the printing device; its characteristic is that the guiding system is a non-fixed guide rail type guiding system, and the non-fixed guide rail type guiding system can generate a guiding path according to needs.

[0080] In this way, the fixed guide rail is eliminated and instead generated according to needs, making the control more flexible and convenient.

[0081] Among them, the non-fixed rail guidance system includes multiple positioning points 2 set on the surface of the printing platform, and a positioning guide component is set at each positioning point 2. The positioning points are arranged in an array to form a two-dimensional guidance point cloud array; the guidance system also includes an automatic guided vehicle 3, and the automatic guided vehicle 3 is provided with a point cloud detection sensor 4 that can sense and locate the positioning guide components at each positioning point. A universal wheel system is also provided under the automatic guided vehicle 3 and is connected to a drive motor 5. The drive motor 5 can drive the universal wheel system to turn and travel; the forming cylinder device is installed on the automatic guided vehicle 3.

[0082] In this way, when this equipment is in use, it can rely on point cloud detection sensors to detect the position of positioning guide components at various positioning points, control the AGV to move forward between different positioning points, and rely on the two-dimensional guidance point cloud array to control the planning and generation of the driving path, so that the forming cylinder device can follow the AGV on the printing platform and complete the docking between different printing devices, thereby realizing the printing of different materials in different parts of a product to meet the performance requirements of different parts. At the same time, it has the advantages of flexible and changeable control, better ability to avoid interference, and realize more printing sequence possibilities; the number of printing stations and AGVs can be arranged according to actual production needs.

[0083] Wherein, the positioning guide component is an electromagnetic generator, and the point cloud detection sensor 4 is a magnetic navigation sensor.

[0084] In this way, the electromagnetic generators can be turned on and off by a computer or other control device. During use, the electromagnetic generators along the desired driving path are turned on, and the electromagnetic generators along the driving path are connected in series, creating an effect similar to a guiding magnetic strip. At the same time, the remaining electromagnetic generators are turned off, and the magnetic navigation sensor is used to guide the AGV along the path. This allows for the generation of different driving paths based on the needs of the corresponding AGV, better avoiding interference from other AGVs. This allows multiple printing stations and a large number of AGVs to be deployed on the printing platform, allowing more AGVs to work together on the same printing platform and participate in printing, greatly improving efficiency. At the same time, the driving path blocks interference from other positioning points, greatly improving the reliability and stability of the driving path.

[0085] The positioning guide component is buried below the upper surface of the printing platform 1 .

[0086] This improves protection and extends lifespan.

[0087] Among them, each positioning point also includes at least one wireless charging position 6, and a wireless charging device is buried under the wireless charging position 6. A wireless charging coil 7 is also correspondingly provided in the middle of the lower surface of the automatic guided vehicle. The wireless charging coil 7 is connected to the battery installed on the automatic guided vehicle, and the battery is connected to the drive motor 5.

[0088] In this way, the automatic charging and driving endurance of the automatic guided vehicle can be achieved, making it more convenient to control the movement sequence and path of the automatic guided vehicle.

[0089] At least part of the wireless charging positions 6 are located at the printing stations on the printing platform.

[0090] In this way, it is convenient for the automatic guided vehicle to drive into the printing station and charge while waiting for printing, so that the charging process does not occupy working time.

[0091] The automatic guided vehicle is further provided with a wireless communication control module 8, which is connected to the drive motor and realizes control.

[0092] In this way, it is convenient to control the automatic guided vehicle to move along the planned path through wireless communication with a computer or other control device at a distance.

[0093] The AGV or printing station is also equipped with a positioning sensor 9, and a corresponding positioning sensor detection member (not shown) is also provided on the printing station or AGV. During implementation, the positioning sensor detection member is installed in the positioning sensor detection member mounting hole 10 on the mounting bracket 20 of the printing station.

[0094] In this way, when the automatic guided vehicle arrives at the printing station, it can rely on the coordinated detection between the positioning sensor and the positioning sensor detection component to achieve accurate positioning of the automatic guided vehicle, better ensure that the forming cylinder device on the automatic guided vehicle and the printing device on the printing station can be accurately docked, and ensure printing quality.

[0095] The positioning sensor 9 is preferably a contact switch, and the positioning sensor detection component is a hard component that can cooperate with the contact switch to achieve contact detection.

[0096] This has the advantages of simple structure, convenient implementation and reliable use.

[0097] There are two pairs of contact switches respectively mounted on contact switch mounting brackets 11 arranged upward on both sides of the automatic guided vehicle. The positioning sensor detection component is a contact protrusion formed on a pair of mounting brackets 20 corresponding to the printing station.

[0098] In this way, the precise positioning of the automatic guided vehicle at the printing station can be more conveniently achieved.

[0099] The universal wheel system includes four Mecanum wheels 12 installed at the four corners below the AGV, and each Mecanum wheel 12 is connected to a corresponding drive motor 5.

[0100] In this way, the drive motor drives the four Mecanum wheels to rotate at different speeds, allowing the AGV to move in different directions, thus better controlling the AGV's steering. Mecanum wheels are a mature, existing product, and their specific structure is not described in detail here.

[0101] Among them, the automatic guided vehicle 3 includes a horizontally arranged base plate, the Mecanum wheel 12 and the corresponding drive motor 5 are installed below the base plate, the forming cylinder device is installed above the middle part of the base plate, the point cloud detection sensor 4 is installed below the base plate, the wireless charging coil 7 is installed below the base plate, and the wireless communication control module 8 is installed above the base plate.

[0102] In this way, the functions of each component can be more easily realized.

[0103] Among them, the forming cylinder device includes a forming cylinder 13 fixedly mounted overhead at a position above the middle part of the automatic guided vehicle. The upper end of the forming cylinder has a circle of flange extending horizontally outward to form a printing plane 14. The bottom plate tray 15 of the forming cylinder can be slid up and down to fit on the inner wall of the forming cylinder. The forming cylinder device also includes a lifting device 16 installed on the automatic guided vehicle below the forming cylinder. The telescopic arm of the lifting device 16 is supported upward and connected to the lower surface of the bottom plate tray.

[0104] In this way, the lifting device lifts the base plate tray upward to a position above the inner cavity of the build cylinder, and then begins to spread powder and print. After each layer is printed, the lifting device retracts downward by one layer, and then spreads powder and prints again in the inner cavity of the build cylinder, and then descends layer by layer until printing is completed. Therefore, it has the characteristics of simple structure, easy control, stability and reliability.

[0105] The four corners of the lower end of the forming cylinder are provided with downward supporting columns 17, and the upper end of the forming cylinder is provided with a supporting frame 18 arranged obliquely outward and downward below the flange.

[0106] In this way, the stability of the forming cylinder can be better guaranteed.

[0107] A waste holding tank 19 is also provided on the printing plane at the front end of the forming cylinder.

[0108] In this way, the waste generated during paving can fall down, which can better assist in paving.

[0109] Among them, the printing station is formed by multiple pairs of mounting brackets 20 installed in pairs at intervals on one side of the printing platform. The mounting bracket 20 is in the shape of an inverted L-shaped arm as a whole, and the front end of the arm extends horizontally forward in the direction away from the edge of the printing platform. The printing device is fixed on the mounting bracket 20.

[0110] In this way, the installation of the printing device is more convenient, and the docking of the forming cylinder device and the printing device is more convenient.

[0111] Among them, the printing device includes a Y-axis guide rail 21 installed on the upper end arm of the mounting bracket along the length direction of the arm, and an X-axis guide rail 22 is vertically arranged between the two Y-axis guide rails 21 in the horizontal direction. The two ends of the X-axis guide rail 22 are slidably fitted on the Y-axis guide rail 21, and a Y-axis motion control mechanism is provided for controlling the sliding of the X-axis guide rail on the Y-axis guide rail. A print head bracket 23 is slidably fitted on the X-axis guide rail and an X-axis motion control mechanism is provided for controlling the sliding of the print head bracket 23 on the X-axis guide rail. A print head bracket is installed on the print head bracket (only the print head mounting hole is shown in the figure); the printing device also includes a powder supply mechanism installed above the rear end position of the mounting bracket, and also includes a powder spreading mechanism.

[0112] This makes it easier to control the X and Y motion of the print head.

[0113] Among them, the Y-axis motion control mechanism is a Y-axis electric slide, the guide rail 24 of the Y-axis electric slide constitutes the Y-axis guide rail on one side, the slide 25 of the Y-axis electric slide and one end of the X-axis guide rail 22 are fixed, and the Y-axis guide rail on the other side is a linear guide rail 26, and the other end of the X-axis guide rail 22 can be slidably engaged on the linear guide rail 26.

[0114] In this way, it has the advantages of simple structure, convenient control and reliable control accuracy.

[0115] The X-axis motion control mechanism is an X-axis electric slide. The guide rail 27 of the X-axis electric slide forms the X-axis guide rail, and the print head holder 23 is mounted on the slide of the X-axis electric slide. The electric slide is an existing product, comprising a motor, guide rails, and a slide. The motor drives the slide along the guide rails via a screw-nut pair. The specific structure is not described here.

[0116] In this way, it has the advantages of simple structure, convenient control and reliable control accuracy.

[0117] Among them, the powder supply mechanism includes a powder box 30, a discharge port is provided at the lower part of the powder box 30, a quantitative discharge mechanism is provided at the discharge port, and a discharge shuttle groove 31 extending forward and downward is connected to the bottom of the quantitative discharge mechanism, and the groove at the lower end of the discharge shuttle groove 31 is horizontally arranged along the width direction between the two corresponding mounting brackets.

[0118] In this way, it is convenient for the powder supply mechanism to quantitatively discharge powder according to the amount required for each spreading, and it is convenient for the powder to be fed into the powder spreading mechanism.

[0119] Among them, the quantitative discharging mechanism includes a metering sleeve horizontally arranged at the discharge port, and the discharge port is connected to the metering sleeve 32 through the upper and lower parts. A metering roller 33 is coaxially arranged at the internal axis of the metering sleeve. Rectangular blades extending along the axial direction are evenly distributed on the circumferential outer surface of the metering roller 33. The length of the rectangular blades is consistent with the length of the inner cavity of the metering sleeve, and the outer surface and the inner cavity wall of the metering sleeve are rotatably fitted. One end of the metering roller 33 can rotatably pass through the end of the metering sleeve and is connected to a metering servo motor 34.

[0120] In this way, the metering servo motor can be used to control the rotation of the metering roller. Each time it rotates a fixed angle, the cavity between the two blades can be used to scrape a fixed volume of powder downward to ensure uniform quantitative powder supply.

[0121] The two ends of the powder box 30 are fixed on the side of the vertically arranged powder box mounting plate 35, the lower end of the powder box mounting plate 35 is fixed to the mounting bracket, and the metering servo motor 34 is fixed on the other side of the powder box mounting plate.

[0122] This makes it easier to install and fix the powder supply mechanism.

[0123] Among them, the powder spreading mechanism includes a powder receiving trough 36 arranged horizontally along the width direction between two corresponding mounting brackets. The two ends of the powder receiving trough 36 are suspended and fixed below the X-axis guide rail near the two ends through upward connecting plates 37. The powder receiving trough is set through from top to bottom and has a downwardly set scraper 38 on the side of the rear end (the end adjacent to the powder box). The lower end of the scraper 38 has a horizontal blade located at the height of the printing plane. The powder receiving trough can accommodate at least one layer of powder required for printing at a time. When the X-axis guide rail slides to the rear end of the Y-axis guide rail, the upper end of the powder receiving trough can be docked with the lower end notch of the discharge shuttle trough.

[0124] In this way, when spreading powder, the powder holding trough follows the X-axis guide rail and slides to the rear end of the Y-axis guide rail. Powder is quantitatively discharged from the quantitative discharging mechanism and falls into the powder holding trough through the discharging shuttle trough. Then, as the X-axis guide rail slides forward along the Y-axis guide rail, the scraper is used to scrape the powder that has fallen into the powder holding trough flat, completing the spreading process. This method of using a scraper for spreading powder is more convenient and the powder surface is smooth. In addition, the spreading mechanism and print head are both integrated on the X-axis guide rail. The print head can follow the spreading mechanism and print immediately during the spreading process. Moreover, each print head can print once during each reciprocating spreading process, improving printing quality and efficiency.

[0125] Among them, a front L-shaped front nozzle mounting plate 40 is installed downwardly and connected to the front side of the print head bracket, and a first print nozzle is installed on the horizontal part structure at the lower end of the front nozzle mounting plate 40 (only the nozzle mounting hole is shown in the figure).

[0126] In this way, as the powder spreading device moves forward with the X-axis guide to spread the material, the print head is controlled to spray a layer of binder in front of the X-axis guide according to the contour of the product layer, completing a pre-print. The powder is then laid on top, combined with the binder, and smoothed by the scraper. Then, as the X-axis guide returns, the print head is controlled to print normally again. This achieves a single layer of spreading and two prints, which can improve the strength of the formed product and increase the thickness of each printed layer to improve printing efficiency. At the same time, the overall structure is simpler, and material spreading is convenient, fast, and reliable.

[0127] In this embodiment, the front nozzle mounting plate 40 is fixed to the front end side of the print head bracket 23; a rear nozzle mounting plate 41 in a backward L-shape is also installed on the rear end side of the print head bracket 23, and a second print nozzle is installed on the horizontal part structure at the lower end of the rear nozzle mounting plate 41 (only the print nozzle mounting hole is shown in the figure), and the print head bracket 23 is also provided with a nozzle vertical motion control mechanism for controlling the vertical sliding of the rear nozzle mounting plate.

[0128] In this way, when the X-axis guide rail moves back to the rear end of the Y-axis guide rail to load the material, the vertical motion control mechanism of the nozzle can control the second print nozzle to rise above the height of the discharge shuttle slot to avoid interference. Then, during normal printing, the second print nozzle is controlled to fall back to the printing position, so that the two print nozzles relying on this structure can achieve at least two prints during the process of the material laying mechanism moving forward with the X-axis guide rail to lay the material back and forth. For example, during normal printing, the first print nozzle and the second print nozzle can be set to their original position at the same height level as the scraper. When the material laying device lays the material forward, the second print nozzle at the rear achieves the first print of the layer of powder. After the material laying device completes the back and forth return of the layer of powder, the first print nozzle at the front achieves the second print of the layer of powder. Therefore, laying the material once and printing twice can better improve product quality and efficiency. The contour of the product printed for the second time can also take the area between the contours of the products laid before and after the two times, so as to better improve the connection effect of the contour between the two times of powder laying and better improve product precision. At the same time, because the two prints use different print heads, they can also use different binders with different ratios, making their respective performance more targeted. For example, the first print uses a binder that produces normal 3D printing results, while the second print uses a binder that can better improve the bonding effect between the printed powder layer and the powder layer to be laid. This can better improve the final printing effect and enhance product quality. In addition, for some special products, such as those with a uniform width in the front-to-back direction, this device can even achieve the special effect of printing four times in a single round trip laying process, further improving product quality and production efficiency.

[0129] Among them, the vertical motion control mechanism of the nozzle includes a vertical guide rail 42 fixed vertically on the print head bracket, one side of the upper end of the rear nozzle mounting plate 41 can be slidably engaged on the vertical guide rail 42, and a nozzle vertical motion control motor 43 is fixedly provided on the upper end of the vertical guide rail 42, and also includes a screw 44 arranged in parallel with the vertical guide rail at an interval. The nozzle vertical motion control motor is connected to the screw and can drive the screw to rotate. A nut 45 is screwed on the screw 44, and the nut is relatively fixed to the upper end of the rear nozzle mounting plate.

[0130] In this way, the vertical movement of the nozzle is controlled by the motor, which rotates the screw. The vertical guide rail limits the rotation of the nut through the front nozzle mounting plate. The screw-nut transmission pair formed by the screw and nut drives the rear nozzle mounting plate to achieve vertical sliding control. The result is a simple structure, reliable control, stable movement, and high control accuracy.

[0131] In addition, a computer-aided control system needs to be installed during implementation. The control system horizontally slices the imported three-dimensional CAD model, separates the slice data of each printing layer, and then sends the slice data to the 3D printer for printing. This is a mature existing technology and will not be described in detail here.

[0132] Second embodiment.

[0133] Compared with the first embodiment, this embodiment differs only in the print head mounting structure of the printing device. In this embodiment, the rear print head mounting plate and the second print head thereon are not provided, but the front print head mounting plate is vertically slidable. The rest of the structure is the same as that of the first embodiment.

[0134] Specifically. Figure 11 In this embodiment, a nozzle vertical motion control mechanism for controlling the vertical sliding of the front nozzle mounting plate 40 is further provided on the print head bracket 23 .

[0135] In this way, the height of the first print head position can be adjusted up and down, so that the position of the print head can be adjusted for both prints during a single material laying process so that it prints close to the upper surface of the powder material, thereby better improving printing accuracy. Specifically, when the first print head moves forward with the X-axis guide to print before laying the material, its position can be adjusted downward so that the first print head is at a position one layer of powder height lower than the scraper, completing the binder jet printing close to the upper surface of the previous layer of powder material, thereby better ensuring the contour accuracy of the product printed in this pass. Then, after the first print head moves backward with the X-axis guide to reset, the first print head is adjusted upward to return to a position horizontal with the scraper to achieve normal printing; after the X-axis guide moves backward and resets to the starting end, the printing of this layer is completed, the bottom plate tray in the forming cylinder drops a layer of powder, and the first print head is controlled to move downward the same distance to print the next layer, and this cycle continues until printing is completed. Therefore, it can better improve the overall product appearance quality, and the structure is relatively simple, which is easy to implement.

[0136] Among them, the vertical motion control mechanism of the nozzle includes a vertical guide rail 41 vertically fixed on one side of the print head bracket 23, and one side of the upper end of the front nozzle mounting plate 40 can be slidably engaged on the vertical guide rail 41. A nozzle vertical motion control motor 42 is fixedly provided on the upper end of the vertical guide rail 41, and also includes a screw 43 arranged in parallel with the vertical guide rail. The nozzle vertical motion control motor 42 and the screw 43 are transmission-connected and can drive the screw to rotate. A nut 44 is screwed on the thread on the screw, and the nut 44 is relatively fixed to the upper end of the front nozzle mounting plate 40.

[0137] In this way, the vertical movement of the nozzle is controlled by the motor, which rotates the screw. The vertical guide rail limits the rotation of the nut through the front nozzle mounting plate. The screw-nut transmission pair formed by the screw and nut drives the front nozzle mounting plate to achieve vertical sliding control. This has the characteristics of simple structure, reliable control, stable movement, and high control accuracy.

[0138] The devices of the above two specific embodiments can both realize the following production modes when used.

[0139] 1. Single-Material Part Flow Production: This model is designed for batch production of a wide variety of parts made of a single material in small quantities. During production, the 3D CAD model of the part to be 3D printed is imported into the computer system. The system then assigns the parts to stations according to their serial numbers, such as 1, 2, 3, and so on. An automated guided vehicle (AGV) enters a printing station and begins printing. Upon completion, it automatically exits, awaiting manual processing before the next AGV enters to continue printing.

[0140] 2. Multi-material Part Production: This model overcomes the limitations of existing 3DP (three-dimensional powder deposition) printers, which can only print in a single material. It meets new printing needs while enabling mass production. During production, the 3D CAD model of the part is imported into a computer, which then assigns the different material sections of the part to different stations for the corresponding materials. Printing proceeds from bottom to top. For example, an automated guided vehicle (AGV) prints the bottom material A at station 1, then proceeds to station 2 under computer control to print the middle material B, and then proceeds to station 3 under computer control to print the top material C.

[0141] The computer scheduling process during production can be as follows: assign printing stations to part materials, if it is a single material, assign one station, if it is multiple materials, assign according to the type of material; plan a path for the automatic guided vehicle through the two-dimensional point cloud array, so that it drives into the corresponding printing station; slice the parts from bottom to top, and send the slice section data to the printing station; proceed layer by layer; when it is necessary to switch materials for printing, plan the path again through the two-dimensional point cloud array, and the automatic guided vehicle drives into another station to continue printing.

[0142] The path planning process during production can be as follows: detect the existing position of the automated guided vehicle; avoid the existing position of the guided vehicle; determine whether the target workstation is idle; plan the path; if the planned path is successful, activate the two-dimensional point cloud array covered by the path; if the planned path fails, plan the automated guided vehicle to leave the printing station and drive it into the overtaking buffer zone to wait, and then plan the path again after the target workstation is idle.

[0143] To sum up, this device has the advantages of being able to easily print different materials in one product, and has a simple structure, flexible and convenient control, can improve powder laying accuracy and convenience, and can improve printing efficiency and quality accuracy.

Claims

1. A non-fixed rail guide system for 3D printing, characterized in that: The system comprises a plurality of positioning points arranged on the surface of the printing platform, each of which is provided with a positioning guide member, wherein the positioning points are arranged in an array to form a two-dimensional guiding point cloud array; the guidance system further comprises an automatic guided vehicle, which is provided with a point cloud detection sensor capable of sensing and positioning the positioning guide members at each of the positioning points; a universal wheel system is further provided below the automatic guided vehicle and is connected to a drive motor, which is capable of driving the universal wheel system to steer; a forming cylinder device for 3D printing is mounted on the automatic guided vehicle; The positioning guide component is an electromagnetic generator, and the point cloud detection sensor is a magnetic navigation sensor; The automatic guided vehicle is also provided with a wireless communication control module, which is connected to the drive motor and realizes control; The automatic guided vehicle or the printing station is also provided with a positioning sensor, and a positioning sensor detection component is also correspondingly provided on the printing station or the automatic guided vehicle.

2. The non-fixed rail guide system for 3D printing according to claim 1, wherein: The positioning guide component is buried below the upper surface of the printing platform.

3. The non-fixed rail type guide system for 3D printing according to claim 1, characterized in that: Each positioning point also includes at least one wireless charging position, under which a wireless charging device is buried. A wireless charging coil is also correspondingly provided in the middle of the lower surface of the automatic guided vehicle. The wireless charging coil is connected to a battery installed on the automatic guided vehicle, and the battery is connected to the drive motor.

4. The non-fixed rail type guide system for 3D printing according to claim 3, characterized in that: At least part of the wireless charging positions are located at the printing positions on the printing platform.

5. The non-fixed rail type guide system for 3D printing according to claim 1, characterized in that: The positioning sensor adopts a contact switch, and the positioning sensor detection component adopts a hard component that can cooperate with the contact switch to realize contact detection.

6. The non-fixed rail type guide system for 3D printing according to claim 5, characterized in that: There are two pairs of contact switches which are respectively mounted on contact switch mounting brackets arranged upward on both sides of the automatic guided vehicle. The positioning sensor detection component is a contact protrusion formed on a pair of mounting brackets corresponding to the printing station.

7. The non-fixed rail type guide system for 3D printing according to claim 3, characterized in that: The universal wheel system includes four Mecanum wheels installed at the four corners below the automatic guided vehicle, and each Mecanum wheel is connected to a corresponding drive motor.

8. The non-fixed rail type guide system for 3D printing according to claim 7, characterized in that: The automatic guided vehicle includes a horizontally arranged base plate, the Mecanum wheels and the corresponding drive motors are installed below the base plate, the forming cylinder device is installed above the middle of the base plate, the point cloud detection sensor is installed below the base plate, the wireless charging coil is installed below the base plate, and the wireless communication control module is installed above the base plate.

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