Laser printer and laser powder laying printing device

Abstract

The utility model relates to a laser printer and a laser powder laying printing device, the laser printer comprises a plurality of laser emitters, each laser emitter emits a laser beam, the laser beam emitted by each laser emitter can act on dust to achieve fusion or sintering, the laser beams emitted by the plurality of laser emitters are parallel to each other, and the laser beams are parallel to each other. The plurality of laser beams are vertically emitted into the dust to realize a sintered printing surface, and the working state of each laser emitter is independently controlled. A plurality of laser emitters are adopted, a traditional single-laser point-by-point serial scanning mode is changed, multiple laser beams can synchronously act on different areas of a powder layer, parallel sintering is carried out on a large-area printing area, the single-layer printing time is greatly shortened, the printing efficiency is improved, and the requirement for rapid manufacturing of modern industrial large-scale production is met.

Description

Technical Field

[0001] This application relates to the technical field of toner-spreading printing, and in particular to a laser printer and a laser toner-spreading printing apparatus. Background Technology

[0002] Current laser printing equipment primarily uses a single laser beam for printing. In this method, the laser beam must scan the printing area point by point and line by line to melt or sinter the powder. This process is time-consuming, especially when dealing with large-area or complex printing tasks, where printing efficiency is extremely low and cannot meet the actual needs of large-scale production. Furthermore, prolonged printing increases energy consumption and production costs, and the heat generated during extended operation can also affect printing accuracy and quality.

[0003] Specifically, traditional laser powder-spread printing typically uses a single laser generator, which is extremely inefficient when dealing with large-scale, complex-shaped objects. Because it relies solely on a single laser for sintering or melting, completing a single layer of printing on a large area of ​​powder material takes a significant amount of time, making it difficult to meet the demands of modern industrial rapid production.

[0004] Furthermore, when a single laser operates, its output power is generally constant, making it difficult to precisely control the energy output at each point it scans. This can easily lead to uneven sintering. In the manufacture of devices with extremely high precision requirements, even minute precision deviations can cause a decline in the performance of the entire device or even render it unusable. For example, when encountering objects with complex internal lattice structures or thin-walled features, traditional single lasers cannot flexibly and precisely sinter powder at different locations according to design requirements, resulting in the inability to manufacture complex three-dimensional structures that meet the design intent. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this application is to provide a laser printer and a laser powder-spreading printing device that can improve printing efficiency and accuracy, and enhance the ability to print complex structures.

[0006] The above-mentioned objective of this application is achieved through the following technical solution:

[0007] A laser printer includes a plurality of laser emitters, each laser emitter emitting a laser beam. The laser beam emitted by each laser emitter can act on dust to achieve melting or sintering. The plurality of laser beams emitted by the plurality of laser emitters are parallel to each other and are perpendicularly incident on the dust to achieve sintering of the printing surface. The operating state of each laser emitter is independently controlled.

[0008] As a preferred embodiment of the present invention, the laser printer further includes a driving device that drives a plurality of laser printers to move along a preset moving path. Each laser printer moves along the moving path and its emitted laser beam forms a sintering line on the printing surface. The sintering lines formed by the laser beams emitted by every two adjacent laser printers in a first direction perpendicular to the moving path overlap with each other.

[0009] As a preferred embodiment of the present invention, the overlap length of the sintered lines formed by the laser beams emitted by every two adjacent laser printers along the first direction is greater than or equal to 30% of the width of a single sintered line.

[0010] As a preferred embodiment of the present invention, the area of ​​the overlapping portion of the laser beams emitted by two adjacent laser printers during their movement along the moving path is greater than 30% of the area of ​​any single laser beam.

[0011] As a preferred embodiment of the present invention, the laser emitters are arranged in a “V” shape or in a staggered array.

[0012] As a preferred embodiment of the present invention, a plurality of laser emitters are arranged in a linear array, and the direction of their arrangement forms an angle with the moving path.

[0013] As a preferred embodiment of the present invention, a plurality of laser emitters form a plurality of laser emitter groups, which are arranged sequentially along the first direction. Each laser emitter group includes a plurality of laser emitters, and the direction in which the plurality of laser emitters in each laser emitter group are arranged forms an angle with the moving path. The laser emitter groups do not interfere with each other along the first direction.

[0014] As a preferred embodiment of the present invention, the laser emitter includes a first laser and a plurality of second lasers, the plurality of second lasers being arranged in a ring around the outside of the first laser to form a ring structure of not less than one ring, and the line connecting the second lasers located on opposite sides of the first laser passes through the first laser and is a straight line.

[0015] As a preferred embodiment of the present invention, the laser printer further includes two galvanometers, and a plurality of laser beams are sequentially reflected by the two galvanometers and incident onto the printing surface.

[0016] A laser powder-spreading printing apparatus includes the aforementioned laser printer, and further includes a dust collection device for placing powder and a powder spreading device for leveling and adding powder, wherein the laser printer is connected to the powder spreading device, and the dust collection device is located below the laser printer and the powder spreading device.

[0017] In summary, the beneficial technical effects of this application are as follows:

[0018] 1. This application employs several laser emitters, changing the traditional single-laser point-by-point serial scanning mode, enabling multiple laser beams to act synchronously on different areas of the powder layer, and performing parallel sintering on large-area printing areas, significantly shortening the single-layer printing time and improving printing efficiency to meet the needs of modern industrial mass production for rapid manufacturing.

[0019] 2. This application, by independently controlling the operating status of each laser emitter, can dynamically adjust the power, scanning speed and other parameters of the corresponding laser emitter for different positions on the printing surface, solving the problem of uneven sintering caused by the constant power output of a traditional single laser, realizing fine control of energy output, and significantly improving the dimensional accuracy and forming quality of the printed parts.

[0020] 3. This application independently controls the operating status of each laser emitter. During the printing process, a single laser emitter will reduce its power or stop working depending on the operating conditions, thus avoiding the situation where a single laser emitter's continuous operation shortens its lifespan, as is the case with traditional methods. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a linear array laser printer.

[0022] Figure 2 This is a schematic diagram of the internal structure of a linear array laser printer.

[0023] Figure 3 This is a schematic diagram of a linear array laser printer overlapping method 1.

[0024] Figure 4 This is a schematic diagram of a second method for overlapping linear array laser printers.

[0025] Figure 5 A schematic diagram of forming a sintering line for a laser emitter.

[0026] Figure 6 A schematic diagram of a laser printer with a "V" shaped arrangement.

[0027] Figure 7 A schematic diagram of a laser printer printing a spot in a "V" shape.

[0028] Figure 8 This is a schematic diagram of a laser printer with multiple laser emitters.

[0029] Figure 9 A schematic diagram showing the laser spot printed by a laser printer with multiple laser emitter groups.

[0030] Figure 10 A schematic diagram of a laser printer printing a spot using two staggered arrays.

[0031] Figure 11 A schematic diagram of a laser printer printing a spot using a multi-column staggered array.

[0032] Figure 12 This is a schematic diagram of a multi-directional laser printer.

[0033] Figure 13 A schematic diagram of a laser printer with a multi-directional arrangement printing spot arrangement method 1.

[0034] Figure 14 A schematic diagram of the second method for printing laser spot arrangement using a multi-directional laser printer.

[0035] Figure 15 A schematic diagram of the third method for printing laser spot arrangement using a multi-directional laser printer.

[0036] Figure 16 This is a schematic diagram of the fourth method of laser spot arrangement printed by a multi-directional laser printer.

[0037] Figure 17 This is a schematic diagram of the drive device.

[0038] Figure 18 This is a schematic diagram of a laser printer with dual galvanometers.

[0039] Explanation of reference numerals: 1. Laser printer; 11. Laser emitter; 12. Collimating lens; 13. Field lens; 14. Housing; 101. First laser; 102. Second laser; 2. Printing surface; 3. Driving device; 31. X-direction driving device; 32. Y-direction driving device; 33. Z-direction driving device; 4. Galvanometer; 41. First galvanometer; 42. Second galvanometer; L1. Sintering width; L2. Overlap length; F1. Movement path; F2. First direction; S1. Laser beam area; S2. Area of ​​overlapping portion; C1. Sintering line; C2. Overlap line. Detailed Implementation

[0040] The present application will be further described in detail below with reference to the accompanying drawings.

[0041] A laser printer 1 includes a plurality of laser emitters 11, and a laser emitter controller independently controls the working state of each laser emitter 11.

[0042] Preferably, the laser emission controller is an integrated control unit, which is equipped with a microprocessor module, a power drive circuit and dedicated control software. It establishes a communication connection with each laser emitter 11 through a data bus and can independently control the operating status of each laser emitter 11.

[0043] Specifically, the laser emission controller can receive the three-dimensional model layer data transmitted from the host computer, divide each printing area into sub-regions that match the number of laser emitters 11 based on the built-in algorithm, generate the scanning path and energy parameters corresponding to each sub-region, such as laser power, scanning speed, pulse frequency, etc., and send them to the corresponding laser emitter 11 in the form of digital signals.

[0044] In terms of hardware implementation, the laser emission controller can use existing industrial-grade motion control cards, such as the TwinCAT system from Beckhoff in Germany, combined with customized drive circuits, and is compatible with mainstream 3D model formats such as STL and AMF. It supports the preset and real-time adjustment of process parameters through a human-machine interface.

[0045] The laser emitter 11 is the core device for generating a high-energy-density laser beam. Preferably, it is a semiconductor-pumped solid-state laser (DPSSL) or a fiber laser with an output power of 100W to 1000W, which is suitable for melting and sintering powder materials such as metals and ceramics.

[0046] like Figure 2 As shown, the laser printer 1 also includes a collimating lens 12, a field lens 13, and a housing 14. The collimating lens 12, the field lens 13, and the laser emitter 11 are all mounted on the housing 14. The laser beam emitted by the laser emitter 11 is adjusted by the collimating lens 12 and the field lens 13 in sequence, and then incident perpendicularly onto the powder layer surface of the printing platform in a parallel manner.

[0047] During the printing process, the laser emission controller independently controls the operating status of each laser emitter 11. For thin-walled structural areas requiring high-precision forming, the scanning speed of the corresponding laser emitter 11 can be reduced and the power fine-tuned to ensure uniform energy deposition. For large-area filling areas, the sintering efficiency is improved by increasing the scanning speed and power output. This differentiated control method avoids the uneven sintering problem caused by traditional single-laser constant parameter scanning.

[0048] Furthermore, since each laser beam is incident vertically and scans in parallel, different areas can be processed simultaneously. Compared to single-laser point-by-point serial processing, the printing time for a single layer can be reduced by several times, significantly improving the efficiency of large-scale printing tasks.

[0049] The connection between the laser emission controller and the laser emitter 11 can be wired or wireless, such as Ethernet, RS-485, Bluetooth, or Wi-Fi. Ethernet is preferred to ensure real-time and stable data transmission. The control software incorporates a dynamic path planning algorithm to automatically avoid path conflicts during multi-laser scanning.

[0050] In terms of material adaptability, by independently adjusting the power and scanning parameters of each laser emitter 11, it is compatible with various metal powders such as titanium alloy, stainless steel, and aluminum alloy, as well as ceramic powders, and is especially suitable for manufacturing three-dimensional objects with complex internal lattice, thin-walled features, or suspended structures.

[0051] In a preferred embodiment of the present invention, the laser printer 1 further integrates a driving device 3, which includes an X-direction driving device 31, a Y-direction driving device 32, and a Z-direction driving device 33. Preferably, the X-direction driving device 31 and the Y-direction driving device 32 together constitute a planar motion system for driving the laser emitter 11 array to move along a preset trajectory in a horizontal printing plane. Specifically, the X-direction driving device 31 includes parallel linear guide rails, a servo motor, and a ball screw pair. The servo motor is connected to the ball screw pair via a coupling. When the servo motor drives the ball screw to rotate, the nut slider that cooperates with it moves linearly along the guide rail. The housing 14 is mounted on the nut slider. The Y-direction driving device 32 and the Z-direction driving device 33 are implemented with a similar structure to the X-direction driving device 31, see details below. Figure 17 The X-direction drive device 31 is mounted on the Z-direction drive device 33, and the Z-direction drive device 33 is mounted on the Y-direction drive device 32. In other words, the Y-direction drive device 32 drives the Z-direction drive device 33 to move along the Y direction, the Z-direction drive device 33 drives the X-direction drive device 31 to move along the Z direction, and the X-direction drive device 31 drives the outer casing 14 to move along the X direction. Here, the X, Y, and Z directions are three orthogonal directions in space. Figure 17 The orientation of the linear guide rails of the X-direction drive device 31, Y-direction drive device 32 and Z-direction drive device 33.

[0052] During the printing operation, the X and Y direction drive device 32 drives the laser emitter 11 to scan along the preset moving path F1. Each laser emitter 11 emits a laser beam that continuously acts on the powder layer during its movement, forming continuous or intermittent sintering lines C1 on the printing surface 2. Figure 5 As shown, specifically, the laser emission controller controls the working state of the laser emitter 11, including starting and stopping. When the laser emitter 11 is in the on state, it is driven by the driving device 3, and the laser beam emitted by it illuminates the printing surface 2, forming a spot that forms a sintering line C1 along the moving path F1. When the laser emitter 11 is in the off state, it is driven by the driving device 3, and no sintering line C1 is generated. The starting, stopping and power of multiple laser emitters 11 are controlled according to the printing requirements to meet the printing needs.

[0053] It should be noted that the movement path F1 is the path traversed by the drive device 3 driving the laser emitter 11. Figures 3-5 , Figure 7 , Figure 9, Figure 11 as well as Figures 13-16 The image shows different arrangements of laser emitters 11 and the direction of their movement path F1.

[0054] Figures 3-5 As shown, on the first direction F2 perpendicular to the movement path F1, that is... Figures 3-5 In the vertical direction, there is an overlapping area between the sintering lines C1 formed by the laser beams emitted by every two adjacent laser emitters 11, such as... Figure 5 As shown, an overlapping region is provided between the sintering lines C1 formed by the laser beams emitted by two adjacent laser emitters 11, forming an overlapping line C2.

[0055] Regarding the overlapping region, in a preferred embodiment, such as Figure 3 As shown, along the first direction F2 perpendicular to the moving path F1 of the laser emitter 11, the sintering lines C1 formed by the laser beams emitted by every two adjacent laser emitters 11 overlap each other to form an overlap length L2. The overlap length L2 is set to be no less than 30% of the width of a single sintering line C1. Specifically, the width of the sintering line C1 refers to the width of the melting trajectory formed by a single laser beam scanning the powder layer surface in the first direction F2, i.e., the sintering width L1. In other words, the width of a single sintering line C1 is close to the diameter of the spot formed by the laser beam emitted by a single laser emitter 11 on the printing surface 2, and its value is also related to the energy density of the laser spot and the scanning speed.

[0056] Regarding the overlapping region in another preferred embodiment, such as Figure 4 As shown, in the stationary state, the area formed by the laser beam emitted by the laser printer 1 acting on the printing surface 2 is denoted as the laser beam area S1. When moving along the moving path F1, the laser beams emitted by two adjacent laser printers 1 overlap, and the area of ​​this overlap is denoted as the overlapping area S2. Specifically, the overlapping area S2 is the area of ​​the overlapping portion in the stationary state during the movement; in other words, the overlapping area S2 is the overlapping portion within the laser beam area S1. The overlapping area S2 accounts for more than 30% of the laser beam area S1. Specifically, if the overlapping area S2 formed by two adjacent laser printers 1 is different from the laser beam area S1, both should be calculated, and the lowest value must also meet the requirement that the overlapping area S2 accounts for more than 30% of the laser beam area S1.

[0057] The overlap area ratio is achieved through the coordinated control of the laser emission controller and the drive device 3. The controller first calculates the overlap area ratio based on the three-dimensional model slice data, the preset laser spot parameters, the spacing between several laser emitters 11, and the angle between the arrangement direction of several laser emitters 11 and the driving direction.

[0058] During the printing process, the laser emission controller monitors the energy output and movement speed of each laser beam in real time. When changes in material powder characteristics or printing layer thickness are detected, the controller automatically adjusts the trajectory spacing and energy parameters of adjacent laser beams to ensure that the overlapping area always meets the design requirements.

[0059] Furthermore, the quantitative design of the overlapping area, along with material sintering process parameters such as laser power and scanning speed, achieves synergistic optimization. When printing thin-walled structures, reducing the scanning speed and increasing the overlapping area enables more uniform energy deposition, avoiding localized overheating or incomplete fusion. When processing large-area filling regions, increasing the scanning speed while ensuring an overlapping area ratio greater than 30% balances efficiency and quality. This precise control strategy based on area overlap significantly improves the process stability and adaptability to complex structures in multi-laser collaborative printing.

[0060] The overlap width can be dynamically adjusted via the laser emission controller, typically 30% to 40% of the laser spot diameter. For example, when the spot diameter is 100 μm, the overlap width is set to 30 μm to 40 μm. This overlap design ensures the metallurgical bonding quality between adjacent sintering areas, avoiding incomplete fusion defects. Especially when printing large areas or complex contours, it can significantly improve the overall density and structural integrity of the printed parts.

[0061] The motion control of the drive unit 3 is uniformly coordinated by the laser emission controller, which generates motion commands in the X, Y, and Z directions by analyzing the slice data of the 3D model. During the multi-laser collaborative printing process, the drive unit 3 precisely controls the moving speed and direction of the laser emitter array 11 according to the scanning task allocation of each laser beam, while ensuring the overlap accuracy of the sintering lines C1 of each laser beam.

[0062] As a preferred embodiment of the present invention, such as Figures 6-7 As shown, several laser emitters 11 are arranged in a "V" shape to optimize path coverage and energy distribution during multi-beam collaborative scanning. Each laser emitter 11 is symmetrically distributed at a preset angle on the two sides of the "V". When the driving device 3 drives the emitter array to scan along the moving path F1, the sintering lines C1 of the laser beams on both sides can naturally form an overlapping area perpendicular to the moving direction, reducing the edge scanning blind zone caused by parallel arrangement. This is especially suitable for printing curved or arc-shaped structures, improving the sintering integrity of the edge area.

[0063] As a preferred embodiment of the present invention, such as Figures 10-11 As shown, several laser emitters 11 are arranged in a staggered array to optimize path coverage and energy distribution during multi-beam cooperative scanning. Odd-numbered columns of emitters are offset by a certain distance along the column direction, specifically half the distance between two adjacent laser emitters 11 in each column, as shown below. Figure 10As shown, this creates a staggered layout similar to a chessboard. A more preferred method is, as... Figure 11 As shown, there are n columns of laser emitters 11. The distance between two adjacent laser emitters 11 in each column is a. After the first column, the laser emitters 11 in each column are offset by a / n.

[0064] The staggered design effectively avoids the problem of energy superposition and overheating caused by the overlapping paths of adjacent laser beams during scanning, allowing the sintering line C1 to form an interlaced coverage in the moving direction, eliminating scanning blank areas that may occur in traditional parallel arrangements. For example, when printing a lattice structure with dense fine ribs, the staggered array arrangement can improve the sintering success rate at the intersection of the ribs and significantly reduce incomplete fusion defects.

[0065] As a preferred embodiment of the present invention, such as Figures 1-5 As shown, several laser emitters 11 are arranged in a linear array, and their arrangement direction forms an angle with the moving path F1 of the driving device 3. Specifically, the linear array means that each laser emitter 11 is arranged at equal or variable intervals along a straight line, and the angle between the arrangement direction and the moving path F1 is adjusted according to the printing requirements.

[0066] As a preferred embodiment of the present invention, such as Figures 8-9 As shown, several laser emitters 11 are divided into multiple laser emitter groups, and each laser emitter group is arranged sequentially along a first direction F2 perpendicular to the moving path F1. Each laser emitter group contains a plurality of laser emitters 11, typically 2 to 8 laser emitters 11. The arrangement direction of the laser emitters 11 within the group forms an angle with the moving path F1, and adjacent laser emitter groups along the first direction F2 maintain a safe spatial distance to ensure that they do not interfere with each other during operation.

[0067] Employing multiple laser emitter groups significantly improves printing efficiency and adaptability to complex structures. For example, when printing large aerospace components, using three laser emitter groups, each with four emitters, for parallel scanning, improves efficiency many times over compared to single-group scanning or linearly arranged barcode scanning. When processing medical devices with different density lattice structures, by controlling the power of each laser emitter and managing the overlap area to match material requirements, the density deviation of the printed parts is significantly reduced.

[0068] Furthermore, since the laser emitter groups do not interfere with each other in the first direction F2, they can simultaneously use different parameters such as power and scanning speed for differentiated printing, further expanding the device's ability to support multi-material and multi-process composite printing.

[0069] It is worth noting that the adjacent laser emitter groups in the first direction F2 maintain a safe spatial distance. However, as Figure 9As shown, the areas swept by adjacent laser emitter groups overlap to ensure the integrity of the coverage, and the overlap length L2 of adjacent laser emitter groups accounts for more than 30% of the sintering width L1 of a single laser emitter 11.

[0070] As a preferred embodiment of the present invention, such as Figures 12-16 As shown, the laser emitter 11 adopts a composite layout structure, including a first laser 101 located at the center and several second lasers 102 surrounding it. The second lasers 102 are arranged in a ring array with the first laser 101 as the center, forming at least one ring of concentric structures.

[0071] Example 1, such as Figure 13 As shown, several laser emitters 11 are arranged relatively densely. When moving along the direction shown in the figure, the laser emitters 11 in the shaded area are working while the blank laser emitters 11 are stopped. The line connecting the second lasers 102 located on opposite sides of the first laser 101 passes through the first laser 101 and is a straight line, forming an arrangement similar to the linear array described above. Thus, different laser emitters 11 work during the movement along different directions.

[0072] Example 2, as Figure 14 As shown, several laser emitters 11 are arranged relatively loosely. When moving along the direction shown in the figure, the laser emitters 11 in the shaded area work while the blank laser emitters 11 stop, forming an arrangement similar to the staggered array mentioned above. Thus, different laser emitters 11 work during the movement along different directions.

[0073] Example 3, as Figure 15 As shown, the second laser 102 is arranged in a multi-layered ring array, and the number of second lasers 102 in each layer is the same. The second lasers 102 in each layer correspond one-to-one. The line connecting the second lasers 102 located on opposite sides of the first laser 101 passes through the first laser 101 and is a straight line. In this way, when moving in different directions, a linear array with a longer printing area can be formed.

[0074] Example 4, as Figure 16 As shown, the second laser 102 is arranged in a multi-layered ring array, and the number of second lasers 102 increases with each outer layer. The line connecting the second lasers 102 located on opposite sides of the first laser 101 passes through the first laser 101 and is a straight line. In this way, when moving in different directions, a linear array or a staggered array arrangement can be formed for more directions of movement.

[0075] As a preferred embodiment of the present invention, such as Figure 18The laser printer 1 is further configured with two galvanometers 4, which are sequentially positioned between the collimating lens 12 and the field lens 13. The rotation axes of the two galvanometers 4 are perpendicular, allowing several laser beams to be reflected sequentially by the two galvanometers 4 and then perpendicularly incident on the printing surface 2. The galvanometers 4 are high-speed vibrating reflectors, including a horizontally deflecting first galvanometer 41 and a vertically deflecting second galvanometer 42, which are orthogonally arranged and installed on the optical path between the laser emitter 11 and the printing platform.

[0076] Specifically, the laser beam emitted by each laser emitter 11 first strikes the first galvanometer 41, where it is reflected and its horizontal scanning angle is changed. It is then projected onto the second galvanometer 42, where it undergoes a second reflection and its vertical scanning angle is adjusted, ultimately focusing on the powder layer surface of the printing surface 2. The galvanometer 4 is driven by a high-precision servo motor or voice coil motor. The laser emission controller is connected to the galvanometer 4 via a dedicated drive circuit, sending position commands in real time to ensure that each laser beam scans along a preset path. This causes the light spot pattern formed by the laser emitters 11 to move on the printing surface 2.

[0077] In a preferred embodiment, each laser emitter 11 can be independently configured with a set of galvanometers 4, i.e., two galvanometers 4 form a set. Preferably, an independent galvanometer 4 set design is adopted, i.e., each laser emitter 11 corresponds to two independent galvanometers 4, to avoid signal interference during multi-beam scanning and to achieve independent path planning for each beam. This design allows different laser beams to simultaneously scan different areas on the printing surface 2, and the scanning speed and deflection angle can be set differently.

[0078] The galvanometer 4 and the moving path F1 of the drive device 3 form a coordinated control. When the drive device 3 drives the laser emitter 11 to adjust its height along the lifting direction of the printing platform, the galvanometer 4 compensates for the focal length change through a dynamic focusing algorithm to ensure that the laser beam is always perpendicular to the powder layer surface; when the drive device 3 drives the laser emitter 11 to scan along the plane of the printing platform, the rapid deflection of the galvanometer 4 is combined with the linear motion of the drive device 3.

[0079] By employing a dual-mirror 4-reflection structure, the scanning and positioning time of the laser beam is shortened, the tracking error of complex curve trajectories is reduced, and the accuracy of curved surface contours is improved. In addition, the orthogonal reflection design of the dual-mirror 4 makes the energy distribution of the laser beam on the printing surface 2 more uniform. With the real-time fine adjustment of the deflection angle of the galvanometer 4 by the controller, the overlap width of adjacent sintering lines C1 can be precisely controlled, thereby improving the density of the printed parts.

[0080] It is worth noting that the key point of this application's use of multi-laser printing is that the multiple laser beams are parallel to each other. If they are not parallel, several adverse consequences will occur. For example, non-parallel laser beams will lead to uneven energy distribution. Due to the different angles of each laser beam, the energy superposition on the printing surface 2 is complex and variable. Some areas may experience overheating due to excessive concentration of energy from multiple laser beams. This will not only cause the printing material to over-melt or vaporize, leading to a decline in material properties, but will also easily cause defects such as cracks and deformation in the printed parts, seriously affecting print quality and product reliability.

[0081] On the other hand, non-parallel laser beams can cause inconsistent printing results in different areas during the scanning process. In areas where the laser beams intersect, excessive energy may lead to over-printing; while in areas where the laser beams are sparse, insufficient energy may cause incomplete sintering, resulting in uneven density and strength distribution of the printed parts, which cannot meet the requirements of high-precision and high-quality manufacturing.

[0082] Furthermore, controlling non-parallel laser beams is quite challenging. Due to the complex angular and positional relationships between the various laser beams, achieving precise control and coordinated operation of each beam becomes extremely difficult, increasing the control cost and technical complexity of the equipment.

[0083] Preferably, the housing 14 of the laser printer 1 is provided with a flow channel, which spirals around the housing 14. The flow channel forms an inlet and an outlet on the housing 14. The inlet and outlet are connected to an external liquid supply device to provide coolant. The liquid supply device is equipped with a circulation pump.

[0084] By utilizing the vertical incidence method of the laser beam perpendicularly entering the printing surface 2 and the independent control mechanism, the scanning sequence and energy distribution of multiple lasers are rationally planned, improving the temperature field uniformity during the printing process, reducing thermal stress concentration and material microstructure differences caused by local overheating, and enhancing the uniformity of mechanical properties of the same layer material, thus meeting the stringent requirements for material performance in high-end fields such as aerospace and medical.

[0085] Unlike the traditional single-laser point-by-point serial scanning mode, this method deploys several laser emitters 11 to achieve simultaneous sintering of multiple laser beams parallel and perpendicular to the printing surface 2. This allows for parallel processing of large-area printing areas, significantly shortening the single-layer printing time and meeting the demands of high-efficiency manufacturing in large-scale production. Simultaneously, the shortened printing cycle reduces the continuous operating time of the equipment, minimizing the impact of heat accumulation, improving equipment stability, and reducing energy consumption and production costs.

[0086] A laser powder-spreading printing device includes the aforementioned laser printer 1, and further includes a dust collection device for placing powder and a powder spreading device for scraping and adding powder. Preferably, the laser printer 1 is connected to the powder spreading device via a rigid bracket to form an integrated motion assembly, which can move synchronously along the printing plane under the drive of the drive device 3. The dust collection device is located below the laser printer 1 and the powder spreading device, and is used to receive powder to form the printing surface 2.

[0087] Specifically, the powder spreading device includes a powder storage bin and a powder spreading scraper. The powder storage bin is connected to the powder spreading scraper. The powder storage bin adopts a funnel-shaped structure design. The powder spreading scraper is made of wear-resistant ceramic or hard alloy material, and the blade head is designed with a wedge-shaped structure. The powder spreading device moves together with the laser printer 1. The laser printer 1 performs sintering printing at the front end of the moving direction, and the powder spreading device performs powder spreading and leveling operations at the rear end of the moving direction. The drive mechanism drives the scraper to move along the printing plane at a constant speed, so that the powder output from the storage bin is evenly spread into a powder layer of uniform thickness.

[0088] During the printing operation, the laser printer 1 and the powder spreading device work together; preferably, after one layer of sintering is completed, the drive device 3 drives the laser printer 1 and the powder spreading device to rise along the height direction by a layer thickness distance; more preferably, after one layer of sintering is completed, the height of the laser printer 1 and the powder spreading device remains unchanged, and the bottom of the dust accumulation device descends, causing the printing surface 2 to descend.

[0089] After printing and toner application for one layer, the laser printer 1 and the toner application device return to their initial positions and perform scanning, sintering, toner application, and leveling operations for the next layer, repeating this cycle until the entire part is printed. By integrating the laser printer 1 and the toner application device and synchronizing their movements, the interlayer switching time is shortened, improving toner application efficiency compared to traditional separate structures.

[0090] The printing method of this laser powder-spreading printing device includes the following steps:

[0091] Step S1: Create a 3D model of the item to be printed;

[0092] Step S2: Slice the 3D model to obtain slice data for each layer;

[0093] Step S3: Use a laser emission controller to plan the print file based on the slice data of each layer;

[0094] Step S4: Use a powder spreading device to smooth the powder in the area to be printed;

[0095] Step S5: Print using the laser generator set according to the print file for this layer;

[0096] Step S6: The printing platform supporting the powder is lowered so that the upper surface of the powder moves down. The powder is then added and leveled using a powder spreading device so that the upper surface of the powder after spreading is flush with the upper surface of the initial print.

[0097] Step S7: Print using the laser generator set according to the print file for this layer;

[0098] Step S8, repeat steps S6 and S7 until the item to be printed is complete.

[0099] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A laser printer, characterized in that, It includes several laser emitters (11), each of which emits a laser beam. The laser beam emitted by each laser emitter (11) can act on the dust to achieve melting or sintering. The laser beams emitted by the several laser emitters (11) are parallel to each other. The several laser beams are perpendicular to the dust to achieve sintering of the printing surface (2). The operating state of each laser emitter (11) is independently controlled.

2. The laser printer according to claim 1, characterized in that, It also includes a driving device (3), which drives a plurality of laser printers (1) to move along a preset moving path (F1). Each laser printer (1) moves along the moving path (F1) and its emitted laser beam forms a sintering line (C1) on the printing surface (2). The sintering lines (C1) formed by the laser beams emitted by every two adjacent laser printers (1) along the first direction (F2) perpendicular to the moving path (F1) overlap with each other.

3. The laser printer according to claim 2, characterized in that, The overlap length (L2) of the sintered lines (C1) formed by the laser beams emitted by each two adjacent laser printers (1) along the first direction (F2) is greater than or equal to 30% of the width of a single sintered line (C1).

4. The laser printer according to claim 2, characterized in that, The area (S2) of the overlapping portion of the laser beams emitted by each two adjacent laser printers (1) during their movement along the moving path (F1) is greater than 30% of the area (S1) of any single laser beam.

5. The laser printer according to claim 2, characterized in that, Several of the laser emitters (11) are arranged in a "V" shape or in a staggered array.

6. The laser printer according to claim 2, characterized in that, Several of the laser emitters (11) are arranged in a linear array, with their arrangement direction forming an angle with the moving path (F1).

7. The laser printer according to claim 2, characterized in that, A plurality of laser emitters (11) form a plurality of laser emitter (11) groups, which are arranged sequentially along the first direction (F2). Each laser emitter (11) group includes a plurality of laser emitters (11), and the direction in which the plurality of laser emitters (11) in each laser emitter (11) group are arranged has an angle with the moving path (F1). Each laser emitter (11) group does not interfere with each other along the first direction (F2).

8. The laser printer according to claim 1, characterized in that, The laser emitter (11) includes a first laser (101) and a plurality of second lasers (102). The plurality of second lasers (102) are arranged in a ring around the outside of the first laser (101) to form a ring structure of at least one ring. The line connecting the second lasers located on opposite sides of the first laser (101) passes through the first laser (101) and is a straight line.

9. The laser printer according to claim 1, characterized in that, It also includes two galvanometers (4), and several laser beams are sequentially reflected by the two galvanometers (4) and injected into the printing surface (2).

10. A laser powder-spreading printing apparatus, comprising the laser printer (1) according to any one of claims 1-9, characterized in that, It also includes a dust collection device for placing powder and a powder spreading device for leveling and adding powder, wherein the laser printer (1) is connected to the powder spreading device, and the dust collection device is located below the laser printer (1) and the powder spreading device.

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