3D printing equipment

Abstract

The utility model discloses 3D (three-dimensional) printing equipment, which is characterized in that a precise linear guide rail for a movable frame to slide along the X direction is mounted on a bottom plate of a laser optical chamber right above a forming chamber, and a movable frame driving system drives the movable frame to intermittently move along the X direction; a grating of the precise grating closed-loop system measures the displacement of the movable frame in the X direction and the Y direction in real time, calculates the difference value between the theoretical value and the actual value of the repeated stop precision of the movable frame in real time, and sends the difference value into an STL hierarchical file of a formed part in the control system in real time. The coordinate values of scanning points of all sets of laser scanning modules of the STL hierarchical file are modified in real time, a control system controls all sets of laser scanning modules on a movable frame to adjust the positions of the scanning points according to the modified STL hierarchical file, and a scanning field formed by quantitative powder laying of a powder laying system on a piston of a forming cylinder is scanned; according to the utility model, the overlapping precision of the scanned pattern position and the front layer is ensured.

Description

Technical Field

[0001] This utility model relates to the field of 3D laser printing technology, and in particular to a 3D printing device. Background Technology

[0002] 3D printing equipment for 3C (Computer, Communication, Consumer Electronics) is a rapidly developing and widely used advanced equipment in the contemporary additive manufacturing field, operating on the SLM (Surface Mount Technology) process. Its output and market value have been increasing year by year, comparable to military-grade 3D printing equipment. A key characteristic of 3D printing equipment for 3C is the small scanning area and height of the formed parts, the fewer layers, and the elimination of the need for splicing.

[0003] 3C-type equipment is generally small to medium-sized, using only 1-2 laser beams (only recently have models with 6 laser beams appeared). 3C parts are mass-produced items, making output a primary concern. Furthermore, 3C-type equipment requires high scanning precision; to maintain accuracy, the positional relationship between the galvanometer and the scanning field is fixed. These factors result in a small percentage of laser scanning time relative to auxiliary time (layer changing, powder spreading, cleaning, door opening, part removal, plate loading, door closing, air inflation, and powder spreading) in 3C-type equipment—the "Scanning Time Percentage"—leaving a significant amount of time dedicated to auxiliary tasks, severely impacting production efficiency. Improving the production efficiency of 3C-type 3D printing equipment remains a crucial and unresolved issue for the industry. Summary of the Invention

[0004] To overcome the above deficiencies, this utility model provides a 3D printing device that uses a split-array, sequential displacement, static, and compensation scanning method for laser scanning molding, which can effectively improve product molding accuracy and production efficiency, and ensure the stability of product molding quality.

[0005] The technical solution adopted by this utility model to solve its technical problem is: a 3D printing device, including a laser optical chamber, a forming chamber, a forming cylinder, a forming cylinder drive system, a laser scanning module, a moving frame, a moving frame drive system, a precision grating closed-loop system, a powder spreading system, and a control system. The laser optical chamber is fixedly installed above the forming chamber. A precision linear guide rail extending along the X direction is fixedly installed on the bottom plate of the laser optical chamber. The moving frame is slidably installed on the precision linear guide rail along the X direction. Several sets of laser scanning modules are fixedly installed on the moving frame. The moving frame drive system drives the moving frame to move intermittently along the X direction within the laser optical chamber. The grating of the precision grating closed-loop system measures the displacement of the moving frame in the X and Y directions in real time. The precision grating closed-loop system can calculate in real time the difference (ΔX, ΔY) between the theoretical value and the actual value of the repeatability accuracy of the moving frame. Y), the precision grating closed-loop system communicates with the control system. The precision grating closed-loop system can send the difference value to the STL layered file of the formed part in the control system in real time, and modify the coordinate values ​​of the scanning points of each group of laser scanning modules in the STL layered file in real time. The control system controls each group of laser scanning modules to adjust the scanning point position according to the modified STL layered file. The upper end of the forming cylinder is fixedly and sealed on the forming bottom surface of the forming chamber. The forming cylinder drive system drives the piston of the forming cylinder to descend intermittently, forming a scanning field on the piston of the forming cylinder. The powder spreading system can spread powder quantitatively to the scanning field. The laser beam emitted by each group of laser scanning modules can pass through the light-transmitting plate cover on the upper side of the forming chamber and scan towards the column of scanning fields directly opposite it for forming. The control system controls the forming cylinder drive system, laser scanning module, moving frame drive system and powder spreading system to start and stop intermittently according to the design conditions.

[0006] As a further improvement of the utility model, the scanning field is composed of several columns parallel to the Y-axis, and each column of the scanning field is composed of several scanning partitions arranged along the Y direction. Each group of laser scanning modules on the moving frame can scan one of the scanning partitions in a column of the scanning field directly opposite the moving frame. Each group of laser scanning modules on the moving frame is set to correspond one-to-one with each scanning partition in a column of the scanning field.

[0007] As a further improvement of the utility model, the movable frame includes a high-rigidity simply supported beam frame, a load-bearing base, and a support cover plate. The support cover plate and the load-bearing base are respectively fixedly installed at the upper and lower ends of the simply supported beam frame. The laser scanning module includes a laser, a galvanometer, a collimating lens, and an optical fiber. Several sets of galvanometers are fixedly installed on the load-bearing base at intervals along the Y direction, and several sets of lasers are fixedly installed on the support cover plate at intervals along the Y direction. Each laser is connected to each galvanometer through an optical fiber to realize the transmission of the laser beam.

[0008] As a further improvement of the utility model, the moving frame drive system includes a motor, a lead screw, a lead screw mounting base, and a nut fixing block. The motor and the lead screw mounting base are respectively fixedly installed in the laser optics chamber. Both ends of the lead screw are respectively connected to a lead screw mounting base for axial stop and circumferential rotation. The lead screw extends along the X direction, and one end of the lead screw is connected to the motor power output shaft. The nut fixing block is fixedly installed at the middle position of the moving frame along the Y direction, and the nut fixing block is movably screwed to the lead screw.

[0009] As a further improvement of the utility model, a high-strength horizontal substrate is provided on the bottom surface of the laser optical chamber. The horizontal substrate is provided with several sets of clearance holes that correspond one-to-one with each scanning partition of the scanning field. The laser beam emitted by the laser scanning module can pass through the clearance holes and be directed to each scanning partition in the forming chamber. The high-strength horizontal substrate is provided with two precision linear guide rails extending along the X direction. The two precision linear guide rails are arranged at intervals along the Y direction. The sliders of the two precision linear guide rails are respectively fixedly connected to the lower side of the support base of the moving frame.

[0010] As a further improvement of the utility model, the scanning field is divided into 4 to 6 columns, each column has a scanning field width of 250 to 400 mm, each column is divided into 6 to 10 independent scanning zones, and each group of laser scanning modules emits two laser beams.

[0011] As a further improvement of the utility model, the two gratings of the precision grating closed-loop system are respectively fixedly installed on both sides of the laser optical chamber along the Y direction, and the two gratings read the position data of the moving frame on both sides along the Y direction in real time.

[0012] As a further improvement of the utility model, an air inlet system is provided on one side wall of the molding chamber along the X direction, and an air outlet system is provided on the other side wall of the molding chamber along the X direction.

[0013] As a further improvement of the utility model, the load-bearing capacity of the movable frame is 300-800 kg, the deflection of the movable frame is 0.1 mm / m, and the displacement speed of the movable frame is 125-200 mm / s.

[0014] A method for segmentation, sequential displacement, static, and compensated scanning using this 3D printing equipment, assuming the X-axis and Y-axis extend in two mutually perpendicular directions on a horizontal plane, includes the following steps:

[0015] Step 1: Divide the scanning field: Divide the scanning field into several columns parallel to the Y-axis, and divide each column of the scanning field into several scanning partitions arranged along the Y-direction;

[0016] Step 2: Set up a moving frame that translates along the X-axis above the scanning field. The length and width of the moving frame correspond to a column of scanning fields. Install several sets of laser scanning modules on the moving frame. Each set of laser scanning modules can scan a scanning section in a column of scanning fields.

[0017] Step 3: The moving frame moves intermittently along the positive X-axis above the scanning field. After the moving frame moves from one end of the scanning field to the other, it moves intermittently along the negative X-axis above the scanning field. The moving frame remains stationary for a set time after moving from one column of scanning fields to the next adjacent column.

[0018] Step 4: During the movement of the moving frame, the precision grating closed-loop system outputs the difference (ΔX, ΔY) between the theoretical and actual values ​​of the repeatability accuracy of the moving frame in real time, and sends this difference to the STL layer file of the formed part in real time, thereby modifying the coordinate values ​​of the scanning points of each group of laser scanning modules in real time and forming a modified STL layer file.

[0019] Step 5: The laser scanning module scans its corresponding scanning partition according to the optimized path of the modified STL layered file. After the scanning process is completed, the moving frame moves to the next column position in the scanning field.

[0020] The beneficial technical effects of this utility model are as follows: By dividing the scanning field into multiple columns and mounting the laser scanning module on a moving frame, the moving frame is moved to ensure that the laser scanning module sequentially aligns with the scanning partitions in each column of the scanning field, scanning column by column without skipping columns, thus avoiding idle strokes. During scanning, the moving frame remains stationary, eliminating dynamic errors caused by frame movement. Simultaneously, a precision grating closed-loop system is used to detect and compensate for the positioning accuracy of the moving frame in real time, effectively controlling the positioning accuracy and ensuring extremely high overlap between the scanned graphic position and the previous layer. This fully guarantees the forming accuracy of 3C precision small parts. This utility model achieves one-time forming of a large number of 3C precision small parts through a single column of laser scanning modules in conjunction with a moving frame, resulting in high forming efficiency, a large scanning time ratio, energy savings in equipment and time costs, and avoidance of interference problems associated with assembling too many laser scanning modules. Attached Figure Description

[0021] Figure 1 This is a schematic diagram showing the setting state of the scanning field according to an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of the scanning state of the first column of the scanning field according to the present invention;

[0023] Figure 3 This is a schematic diagram of the scanning state of the 5th column of the scanning field according to this utility model;

[0024] Figure 4 This is a schematic diagram illustrating the principle of the precision grating closed-loop system of this invention for compensating the repetitive stopping accuracy of the moving frame.

[0025] Figure 5 This is a perspective view of the present invention. Detailed Implementation

[0026] Example: A 3D printing device includes a laser optical chamber 40, a forming chamber 50, a forming cylinder 60, a forming cylinder drive system 70, a laser scanning module, a moving frame 20, a moving frame 20 drive system, a precision grating closed-loop system, a powder spreading system, and a control system. The laser optical chamber 40 is fixedly located above the forming chamber 50. A precision linear guide rail 80 extending in the X direction is fixedly installed on the base plate of the laser optical chamber 40. The moving frame 20 is slidably mounted on the precision linear guide rail in the X direction. Several sets of laser scanning modules are fixedly mounted on the moving frame 20. The moving frame 20 drive system drives the moving frame 20 to move intermittently in the X direction within the laser optical chamber 40. The grating 90 of the precision grating closed-loop system measures the displacement of the moving frame 20 in the X and Y directions in real time. The precision grating closed-loop system can calculate in real time the difference (ΔX, ΔY) between the theoretical and actual values ​​of the repeatability accuracy of the moving frame 20. The grating closed-loop system communicates with the control system. The precision grating closed-loop system can send the difference value to the STL layered file of the formed part in the control system in real time, and modify the coordinate values ​​of the scanning points of each group of laser scanning modules 30 in the STL layered file in real time. The control system controls each group of laser scanning modules 30 to adjust the scanning point position according to the modified STL layered file. The upper end of the forming cylinder 60 is fixedly and sealed on the forming bottom surface of the forming chamber 50. The forming cylinder drive system 70 drives the piston of the forming cylinder 60 to descend intermittently, forming a scanning field 10 on the piston of the forming cylinder 60. The powder spreading system can spread powder quantitatively to the scanning field 10. The laser beam emitted by each group of laser scanning modules 30 can pass through the light-transmitting plate cover on the upper side of the forming chamber 50 and scan towards the row of scanning fields 10 directly opposite it for forming. The control system controls the forming cylinder drive system 70, laser scanning modules, moving frame 20 drive system and powder spreading system to start and stop intermittently according to the design conditions.

[0027] The movable frame 20 includes a high-rigidity simply supported beam frame 201, a bearing base 202, and a support cover plate 203. The support cover plate and the bearing base 202 are respectively fixedly installed at the upper and lower ends of the simply supported beam frame 201. The laser scanning module includes a laser 301, a galvanometer 302, a collimating lens 303, and an optical fiber 304. Several sets of galvanometers 302 are fixedly installed on the bearing base 202 at intervals along the Y direction. Several sets of lasers 301 are fixedly installed on the support cover plate at intervals along the Y direction. Each laser 301 is connected to each galvanometer 302 through an optical fiber 304 to realize the transmission of the laser beam.

[0028] The driving system of the moving frame 20 includes a motor, a lead screw 204, a lead screw mounting base 205, and a nut fixing block 206. The motor and the lead screw mounting base 205 are respectively fixedly installed inside the laser optical chamber 40. Both ends of the lead screw 204 are axially stopped and circumferentially rotatable to a lead screw mounting base 205. The lead screw 204 extends along the X-direction, and one end of the lead screw 204 is connected to the power output shaft of the motor. The nut fixing block 206 is fixedly installed at the middle position of the moving frame 20 along the Y-direction and is movably screwed to the lead screw 204. By placing the nut fixing block 206 at the middle position of the moving frame 20, the nut fixing block 206 can be respectively set on the front and rear sides of the simply supported beam frame 201 of the moving frame 20 along the X-axis to improve transmission stability.

[0029] A high-strength horizontal substrate 401 is provided on the bottom surface of the laser optical chamber 40. The horizontal substrate has several sets of clearance holes 4011 corresponding to each scanning zone of the scanning field 10. The laser beam emitted by the laser scanning module can pass through the clearance holes 4011 and be directed to each scanning zone within the forming chamber 50. Two precision linear guide rails 80 extending along the X direction are provided on the high-strength horizontal substrate 401. The two precision linear guide rails 80 are arranged at intervals along the Y direction. The sliders of the two precision linear guide rails 80 are fixedly connected to the lower side of the support base 202 of the moving frame 20. A stable linear drive system is formed by the cooperation of the two precision linear guide rails 80 located on both sides of the moving frame 20 in the Y direction and the lead screw 204 nut drive mechanism located in the middle of the moving frame 20, which can prevent the moving frame 20 from swaying during movement.

[0030] The two gratings 90 of the precision grating closed-loop system are fixedly installed on both sides of the laser optical chamber 40 along the Y direction, and the two gratings 90 read the position data of the moving frame 20 on both sides along the Y direction in real time.

[0031] An air inlet system 501 is provided on one side wall along the X direction inside the molding chamber 50, and an air outlet system 502 is provided on the other side wall along the X direction inside the molding chamber 50. The air inlet system 501 supplies nitrogen gas into the molding chamber 50, so that the product is molded under the protection of inert gas. At the same time, an air field is formed in the molding chamber 50, and the air field carries dust out through the air outlet system 502 to ensure the quality of product molding.

[0032] A method for segmented, sequential displacement, static, and compensated scanning, assuming the X-axis and Y-axis extend in two mutually perpendicular directions on a horizontal plane, includes the following steps:

[0033] Step 1: Divide the scanning field 10: Divide the scanning field 10 into several columns parallel to the Y-axis, and divide each column of the scanning field 10 into several scanning partitions arranged along the Y direction;

[0034] Step 2: Set up a movable frame 20 that translates along the X-axis above the scanning field 10. The length and width of the movable frame 20 correspond to a column of scanning fields 10. Several sets of laser scanning modules 30 are installed on the movable frame 20. Each set of laser scanning modules 30 can scan a scanning partition in a column of scanning fields 10.

[0035] Step 3: The moving frame 20 moves intermittently along the positive X-axis above the scanning field 10. After the moving frame 20 moves from one end of the scanning field 10 to the other end in the X direction, the moving frame 20 moves intermittently along the negative X-axis above the scanning field 10. After the moving frame 20 moves from one column of scanning fields 10 to the next adjacent column of scanning fields 10, it remains stationary for a set time.

[0036] Step 4: During the movement of the moving frame 20, the precision grating closed-loop system outputs the difference (ΔX, ΔY) between the theoretical and actual values ​​of the repeatability accuracy of the moving frame 20 in real time, and sends the difference to the STL layer file of the formed part in real time, thereby modifying the coordinate values ​​of the scanning points of each group of laser scanning modules 30 in real time and forming a modified STL layer file.

[0037] Step 5: The laser scanning module scans its corresponding scanning partition according to the optimized path of the modified STL layer file. After the scanning process is completed, the moving frame 20 moves to the next column position of the scanning field 10.

[0038] This invention divides the scanning field 10 into several columns parallel to the Y-axis, and then further divides each column of the scanning field 10 into several independent scanning partitions along the Y-direction. Several sets of laser scanning modules 30 are mounted on a moving frame 20. The moving frame 20 carries the laser scanning modules and moves sequentially and intermittently along the X-direction. Each time it moves, it reaches above a column of the scanning field 10, and a set of laser scanning modules 30 scans each scanning partition one by one. During laser scanning, the moving frame 20 remains stationary. When the moving frame 20 moves, the laser scanning modules stop scanning. In this way, each column of the scanning field 10 is scanned sequentially along the X-axis. After scanning one layer of the scanning field 10, the moving frame 20 moves in the reverse direction, and then the scanning field 10 is scanned in reverse column by column again. In this invention, the moving frame 20 is completely stopped during scanning. This stationary state can eliminate dynamic errors in the movement of the moving frame 20, such as micro-vibration, micro-swaying, and micro-bumps. This stationary positioning is repeated, thus raising the issue of repeatability accuracy across layers in the same column. The frame's positioning accuracy is ensured by the closed-loop control of the precision grating 90. Simultaneously with the completion of the moving frame 20's movement, the grating 90 of the precision grating closed-loop system measures the position of the moving frame 20 in real time. The precision grating closed-loop system then calculates and outputs the difference (ΔX, ΔY) between the theoretical and actual values ​​of the repeatability accuracy of the moving frame 20 in real time. This difference is then sent to the STL layer file of the formed part in real time, thereby modifying the coordinate values ​​of the scanning points of each group of laser scanning modules 30 in real time, and generating a modified STL layer file, ensuring that each group of laser scanning modules 30... During scanning, the scanning points are automatically adjusted to ensure that the overlap accuracy between the scanned graphic position and the previous layer is ≤0.5~1μm. This fully guarantees the forming accuracy of 3C precision small parts. This method of automatic calculation and compensation through a precision grating closed-loop system avoids the practice of improving the frame's repeated stopping accuracy through hardware, thereby greatly reducing the cost of the positioning system of the moving frame 20 and the requirements for the rigidity of related mechanical structures. The moving frame 20 of this utility model moves along the positive X direction in the order of columns 1, 2, 3, 4, 5... or in the opposite direction along the negative X direction in the order of columns 5, 4, 3, 2, 1. Skipping columns is not allowed. The purpose of sequential movement is to avoid idle travel.

[0039] In step one, the scanning field 10 is divided into 4 to 6 columns, each column of the scanning field 10 is 250 to 400 mm wide, and each column of the scanning field 10 is divided into 6 to 10 independent scanning partitions. Each group of laser scanning modules 30 emits two laser beams.

[0040] One embodiment is as follows: The scanning field 10 is divided into 5 columns (column 1, column 2, column 3, column 4 and column 5, respectively), and each column is divided into 8 independent scanning partitions (column 1 is divided into scanning partition 1-1, scanning partition 1-2, scanning partition 1-3... scanning partition 1-8; column 2 is divided into scanning partition 2-1, scanning partition 2-2, scanning partition 2-3... scanning partition 2-8; column 3 is divided into scanning partition 3-1, scanning partition 3-2, scanning partition 3-3... scanning partition 3-8; column 4 is divided into scanning partition 4-1, scanning partition 4-2, scanning partition 4-3... scanning partition 4-8; column 5 is divided into scanning partition 5-1, scanning partition 5-2, scanning partition 5-3... scanning partition 5-8). The width of each column in the X direction is 300mm, and the length of each scanning partition in the Y direction is 200mm. The size of the entire scanning field 10 is 1500mm × 1600mm.

[0041] Each scanning zone corresponds to two laser beams for scanning. During scanning, after scanning the first column of a layer, the moving frame 20 moves to the right to the position of the second column, stops (only 2 seconds), and then begins scanning the adjacent second column. This process is repeated until all 5 columns of a layer are scanned. Then, the powder is spread on a new layer, and scanning is performed again in the sequence of columns 5, 4, 3, 2, and 1. The product of this invention requires tens of thousands of back-and-forth scans. After completing the scanning of all parts in this batch, auxiliary work is required (powder cleaning, plate pushing-part removal, plate loading, cylinder lifting, air filling-powder spreading). Clearly, the time consumed in its auxiliary work corresponds to the scanning work of 16×5=80 laser beams; while most 3C products, due to their small size, are scanned using small to medium-sized equipment. One auxiliary work of small to medium-sized equipment (similar to the steps of the large equipment in this invention, with almost the same time consumption) corresponds to the scanning work of 2 to 6 laser beams with the same number of layers. It can be seen that the "scanning time ratio" value of this invention is greatly improved, thereby greatly improving production efficiency.

[0042] Preliminary estimates suggest that the production efficiency of 10 units of 16-beam SLM-3C equipment (scanning volume: 1600×1500×250mm³) is equivalent to that of 150 units of 2-beam SLM equipment (scanning volume: 220×140×200mm³). 3 The production efficiency of the two is comparable. Clearly, the latter's costs for factory construction, production operations, logistics management, automation, and energy consumption far exceed those of the former.

[0043] This utility model uses a movable frame 20 to install a group of laser scanning modules 30 (laser 301, galvanometer 302, collimating lens 303 and optical fiber 304) corresponding to a scanning field 10. On the one hand, it can avoid the problems of interference and insufficient installation caused by fixing the laser scanning module in each scanning zone, and on the other hand, it can greatly reduce equipment cost and maintenance cost, and reduce installation difficulty.

[0044] The movable frame 20 is installed in the laser optical chamber of the 3D printing equipment. The movable frame 20 is guided by a precision linear guide rail 80 extending along the X-axis. The motor drives the movable frame 20 through a precision lead screw 204 nut system. The X displacement of the movable frame 20 towards the side walls is measured by precision gratings 90 located on both sides of the movable frame 20 in the Y direction. The precision grating closed-loop system performs closed-loop calculation based on the measurement data of the two precision gratings 90 to obtain the difference (ΔX, ΔY) between the theoretical value and the actual value of the repeatability accuracy of the movable frame 20.

[0045] The displacement of the two sides of the moving frame 20 is measured by two gratings 90 extending along the X direction. Then, the scanning point data of each laser beam in the X and Y directions can be obtained by calculation. The difference between these data and the theoretical position can be obtained as the difference between the theoretical and actual values ​​of the repeatability accuracy of the moving frame 20 (ΔX, ΔY). By compensating for this difference, the position of each layer can be kept consistent during laser scanning forming, avoiding misalignment between layers and ensuring the stability of forming accuracy and product quality.

[0046] The movable frame 20 adopts a high-rigidity simply supported beam system. The load-bearing capacity of the movable frame 20 is 300-800 kg, the deflection of the movable frame 20 is 0.1 mm / m, and the displacement speed of the movable frame 20 is 125-200 mm / s.

Claims

1. A 3D printing device, characterized by: The application relates to a laser 3D printing system, which comprises a laser optical chamber (40), a forming chamber (50), a forming cylinder (60), a forming cylinder driving system (70), a laser scanning module, a moving frame, a moving frame driving system, a precision grating closed loop system, a powder laying system and a control system, the laser optical chamber is fixed above the forming chamber, a precision linear guide rail (80) extending along the X direction is fixedly installed on the bottom plate of the laser optical chamber, the moving frame can slide along the X direction and is installed on the precision linear guide rail, a plurality of groups of laser scanning modules are fixedly installed on the moving frame, the moving frame driving system drives the moving frame to intermittently move along the X direction in the laser optical chamber, the grating (90) of the precision grating closed loop system respectively measures the real-time displacement of the moving frame in the X direction and the Y direction, the precision grating closed loop system can calculate the difference between the theoretical value and the actual value of the repeated stop position precision of the moving frame in real time, the precision grating closed loop system communicates with the control system, the precision grating closed loop system can send the difference into the STL layered file of the control system in real time, the coordinate values of the scanning points of each group of laser scanning modules in the STL layered file are modified in real time, the control system controls each group of laser scanning modules to adjust the scanning point positions according to the modified STL layered file, the upper end of the forming cylinder is fixedly and sealingly installed on the forming bottom surface of the forming chamber, the piston of the forming cylinder is driven by the forming cylinder driving system to intermittently descend, a scanning field is formed on the piston of the forming cylinder, the powder laying system can quantitatively lay powder on the scanning field, the laser beams emitted by each group of laser scanning modules can penetrate through the light-transmitting plate cover plate on the upper side of the forming chamber and scan and form a column of scanning fields opposite to the light-transmitting plate cover plate, and the control system controls the forming cylinder driving system, the laser scanning module, the moving frame driving system and the powder laying system to intermittently start and stop working according to the design conditions.

2. The 3D printing device of claim 1, wherein: The scanning field is composed of a plurality of columns along the Y axis, each column of scanning field is composed of a plurality of scanning sub-zones arranged along the Y direction, each group of laser scanning modules on the moving frame can scan one scanning sub-zone in a column of scanning fields opposite to the moving frame, and each group of laser scanning modules on the moving frame is arranged in one-to-one correspondence with each scanning sub-zone in a column of scanning fields.

3. The 3D printing device according to claim 1 or 2, characterized in that: The moving frame comprises a simply supported beam frame (201) with high rigidity, a bearing base (202) and a supporting cover plate (203), the supporting cover plate and the bearing base are fixedly installed on the upper and lower ends of the simply supported beam frame respectively, the laser scanning module comprises a laser (301), a galvanometer (302), a collimating mirror (303) and an optical fiber (304), a plurality of groups of galvanometers are fixedly installed on the bearing base and are arranged at intervals along the Y direction, a plurality of groups of lasers are fixedly installed on the supporting cover plate and are arranged at intervals along the Y direction, and each laser is connected with each galvanometer through the optical fiber to realize the transmission of the laser beam.

4. The 3D printing device of claim 3, wherein: The mobile frame driving system comprises a motor, a screw rod (204), a screw rod mounting seat (205) and a nut fixing block (206), the motor and the screw rod mounting seat are fixedly installed in the laser optical chamber respectively, the screw rod is connected with one screw rod mounting seat in axial stop and circumferential rotation respectively, the screw rod extends along the X direction, one end of the screw rod is connected with the power output shaft of the motor, the nut fixing block is fixedly installed at the middle position of the mobile frame along the Y direction, and the nut fixing block is movably screwed with the screw rod.

5. The 3D printing device of claim 3, wherein: The bottom surface of the laser optical chamber is provided with a high-strength horizontal base plate (401), a plurality of groups of avoidance holes (4011) corresponding to each scanning sub-area of the scanning field are arranged on the horizontal base plate, the laser beams emitted by the laser scanning module can pass through the avoidance holes and are emitted to each scanning sub-area in the forming chamber, two precise linear guides extending along the X direction are arranged on the high-strength horizontal base plate, the two precise linear guides are arranged in interval along the Y direction, and the sliders of the two precise linear guides are fixedly connected with the lower side of the bearing base of the mobile frame.

6. The 3D printing device of claim 2, wherein: The scanning field is divided into 4-6 columns, the scanning field width of each column is 250-400 mm, each column of scanning field is divided into 6-10 independent scanning sub-areas, and each group of laser scanning module emits two laser beams.

7. The 3D printing device of claim 1, wherein: The two gratings of the precise grating closed loop system are fixedly installed on the two sides of the laser optical chamber along the Y direction, and the two gratings read the position data of the two sides of the mobile frame along the Y direction in real time.

8. The 3D printing device of claim 1, wherein: An air inlet system (501) is arranged on one side wall of the forming chamber along the X direction, and an air outlet system (502) is arranged on the other side wall of the forming chamber along the X direction.

9. The 3D printing device of claim 1, wherein: The bearing capacity of the mobile frame is 300-800 kg, the deflection of the mobile frame is 0.1 mm / m, and the speed of displacement of the mobile frame is 125-200 mm / s.

Images