A mobile scanning method for laser 3D printing

Abstract

The present invention discloses a multi-laser 3D printing mobile scanning method, which belongs to the technical field of 3D printers. The method comprises the following steps: setting a scanning speed vector of a file to be printed, setting a horizontal shift speed vector of a print head, calculating a galvanometer scanning speed vector so that the galvanometer scanning speed vector and the print head horizontal shift speed vector are superimposed to be the same as the scanning speed vector of the file to be printed; starting scanning, the print head, the X-axis galvanometer, and the Y-axis galvanometer maintain uniform motion with the horizontal shift speed vector, and simultaneously rotating the X-axis galvanometer and the Y-axis galvanometer by a motor so that the laser emitted by the print head is reflected by the X-axis galvanometer and the Y-axis galvanometer and scanned at a uniform speed on the printing work surface with the galvanometer scanning speed vector. The galvanometer module of the present invention is always in a uniform motion state, which reduces the time for acceleration and deceleration of the galvanometer module and has higher printing efficiency.

Description

Technical Field

[0001] The present invention belongs to the technical field of 3D printers, and in particular relates to a laser 3D printing mobile scanning method. Background Art

[0002] In 3D printing, SLA, SLS, and SLM use a galvanometer to reflect a single laser beam and perform image scanning and printing on a two-dimensional work plane. In the field of laser scanning additive manufacturing, the scanning format of the galvanometer is limited by factors such as the scanning deflection angle and focal length, resulting in the molding format of a single galvanometer being constrained to within 350mm×350mm. Large-format additive manufacturing equipment often uses a galvanometer combination, that is, a single device is equipped with multiple sets of galvanometer scanning systems. Multi-galvanometer scanning is beneficial to improving the forming efficiency of the equipment, but the bonding strength at the block connection of the parts is reduced due to the power deviation of different sets of lasers. At the same time, the splicing position of the galvanometer depends on the stability of the galvanometer. If the galvanometer drifts for a long time or thermally drifts, it will cause defects at the joints.

[0003] Combining a galvanometer system with linear motion, such as those with authorization publication number CN215932261U, application publication number CN 112775443A, application publication number CN103071795A, and authorization publication number CN202271101U, can achieve large-format printing. In all cases, the galvanometer system is moved to a fixed area, and then the XY axis is fixed and the galvanometer system begins scanning and printing the work area. After the work area is scanned and printed, the XY axis galvanometer moves to the next area, and scanning and printing are performed according to the above process.

[0004] In the aforementioned patent, the galvanometer module's motion is discontinuous; it must move horizontally to a fixed position, stop, and then the galvanometer motor begins driving the XY mirrors to scan and print the laser reflections. This discontinuous motion causes the entire galvanometer mechanism to take time to accelerate and decelerate. The actual galvanometer system and its associated motion system are quite heavy, so acceleration and deceleration unintentionally reduce printing efficiency. Summary of the Invention

[0005] The present invention provides a mobile scanning method for laser 3D printing, which solves the problem of discontinuous movement of the galvanometer module, resulting in reduced printing efficiency, when a galvanometer system combined with linear motion is used in 3D printing technology to achieve large-format printing.

[0006] In order to solve the above technical problems, the technical solution provided by the present invention is:

[0007] The present invention relates to a laser 3D printing mobile scanning method, which comprises the following steps:

[0008] S1. Input the file to be printed and set the scanning speed vector of the file to be printed

[0009] S2. Set the print head horizontal speed vector

[0010] S3. Scan the document to be printed according to the speed vector and the print head horizontal velocity vector Calculate the galvanometer scanning velocity vector Make the galvanometer scanning velocity vector and the print head horizontal movement velocity vector After superposition, the scanning speed vector of the document to be printed same;

[0011] S4. Start scanning, the print head, X-axis galvanometer and Y-axis galvanometer move horizontally at a speed vector Maintaining uniform motion, the X-axis galvanometer and the Y-axis galvanometer are rotated by the motor at the same time, so that the laser emitted by the print head is reflected by the X-axis galvanometer and the Y-axis galvanometer and then moves on the printing work surface at the galvanometer scanning speed vector Perform a uniform scan.

[0012] Preferably, in step S3, the galvanometer scanning velocity vector is calculated The calculation formula is:

[0013]

[0014] Preferably, in step S4, the print head emits laser light to the Y-axis galvanometer, and the Y-axis galvanometer reflects the laser light to the X-axis galvanometer, so that the laser light scans along the Y-axis direction on the X-axis galvanometer. The scanning speed vector is The X-axis galvanometer reflects the laser toward the printing work surface and makes the laser scan along the X-axis direction on the printing work surface. The scanning velocity vector is Scan velocity vector and the scanning velocity vector Satisfy the requirements of formula (2):

[0015]

[0016] Preferably, the formula for the rotational angular velocity of the X-axis galvanometer and the Y-axis galvanometer in step S4 is:

[0017]

[0018]

[0019] In the formula, D is the distance between the X-axis galvanometer and the Y-axis galvanometer, L is the vertical distance from the Y-axis galvanometer to the printing work surface, x is the horizontal coordinate of the current scanning position, y is the vertical coordinate of the current scanning position, V x and V y are the velocity components of the scanning velocity V in the x and y directions, that is, the scanning velocity vector is The magnitude and scanning velocity vector are The size of ω y is the scanning angular velocity of the Y-axis galvanometer pair, ω x is the scanning angular velocity of the X-axis galvanometer pair.

[0020] Preferably, the print heads are arranged in a plurality, and the plurality of print heads are arranged side by side, and the horizontal speed vector of each print head is same.

[0021] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0022] 1. The laser 3D printing mobile scanning method of the present invention is based on the scanning speed vector of the document to be printed. and the print head horizontal velocity vector Calculate the galvanometer scanning velocity vector During the scanning process, the print head, X-axis galvanometer and Y-axis galvanometer move horizontally at a speed vector Maintaining uniform motion, the X-axis galvanometer and the Y-axis galvanometer are rotated so that the galvanometer scanning velocity vector is Therefore, the galvanometer module is always in a uniform motion state, which reduces the time for acceleration and deceleration of the galvanometer module and has higher printing efficiency.

[0023] 2. The laser 3D printing mobile scanning method of the present invention can be provided with multiple sets of print heads, X-axis galvanometers and Y-axis galvanometers, multiple print heads are arranged side by side, and the horizontal movement speed vector of each print head is Similarly, when the wind field needs to be coordinated during the scanning process, the smoke and dust problem can be perfectly avoided, so that large-format printing is not disturbed by smoke and dust, which helps to improve the clarity of large-format 3D printing. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a structural diagram of the laser 3D printing mobile scanning device;

[0025] Figure 2 This is a schematic diagram for determining the scanning direction of the galvanometer;

[0026] Figure 3 This is the principle diagram of inverse galvanometer scanning velocity vector;

[0027] Figure 4 is the galvanometer scanning velocity vector Print head horizontal movement velocity vector And the scanning speed vector of the document to be printed relationship diagram;

[0028] Figure 5 is the scanning speed vector of the document to be printed Converted into galvanometer scanning velocity vector Schematic diagram of;

[0029] Figure 6 It is a schematic diagram of the printing process of large-format 3D printing in the prior art;

[0030] Figure 7 This is a schematic diagram of the printing process of large-format 3D printing in Example 2.

[0031] Label description: 1-print head, 2-Y-axis galvanometer, 3-X-axis galvanometer, 4-laser, 5-printing work surface. DETAILED DESCRIPTION

[0032] In order to further understand the content of the present invention, the present invention is described in detail with reference to the examples. The following examples are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0033] Example 1

[0034] Refer to the attached Figure 1 As shown, the structural diagram of the laser 3D printing mobile scanning device involved in this embodiment includes a group of scanning mechanisms, which include a print head 1, a Y-axis galvanometer 2 and an X-axis galvanometer 3. The print head 1, the Y-axis galvanometer 2 and the X-axis galvanometer 3 are all fixed on a printing beam that can move along the Y-axis direction.

[0035] The laser 3D printing mobile scanning method based on the above-mentioned laser 3D printing mobile scanning device includes the following steps:

[0036] S1. Input the file to be printed and set the scanning speed vector of the file to be printed

[0037] S2. Set the print head horizontal speed vector

[0038] In this step, the print head 1 is fixed on the print beam, so the movement direction of the print head 1 is along the Y axis, and the movement speed of the print head 1 is equal to the translation speed of the print beam;

[0039] S3. Scan the document to be printed according to the speed vector and the print head horizontal velocity vector Calculate the galvanometer scanning velocity vector Make the galvanometer scanning velocity vector and the print head horizontal movement velocity vector After superposition, the scanning speed vector of the document to be printed same;

[0040] Galvanometer scanning velocity vector The scanning direction in Figure 2 The method shown is used to determine that for any target coordinate point to be printed on the printing work surface, assuming that its coordinates are (X, Y), the center position of the current galvanometer printing work surface 4 is (Xt, Yt), and the coordinates of the target coordinate point relative to the center position of the printing work surface 4 are (Xi, Yi), then (Xi, Yi) satisfies the following relationship:

[0041] Xi=X-Xt (3)

[0042] Yi=Y-Yt (4)

[0043] Therefore, for the printing target point, according to its coordinates (X, Y) on the printing work surface 4 and the center position of the current galvanometer printing platform (Xt, Yt), the scanning direction of the galvanometer can be obtained, that is, the coordinates of the target coordinate point relative to the center position of the printing work surface 4 are (Xi, Yi); based on the scanning direction of the galvanometer, the horizontal movement speed vector of the print head and the scanning speed vector of the document to be printed The scanning speed of the galvanometer can be calculated.

[0044] like Figure 3 and Figure 4 As shown, due to the scanning speed vector of the document to be printed Set by step S1, the horizontal speed vector of the print head 1 is Based on the setting in step S2, the galvanometer scanning velocity vector can be obtained by reverse deduction. Galvanometer scanning velocity vector The calculation formula is:

[0045]

[0046] S4. Start scanning, print head 1, X-axis galvanometer 3 and Y-axis galvanometer 2 move horizontally at a speed vector Maintaining uniform motion, the X-axis galvanometer and the Y-axis galvanometer are rotated by the motor at the same time, so that the laser emitted by the print head is reflected by the X-axis galvanometer and the Y-axis galvanometer and then moves on the printing work surface at the galvanometer scanning speed vector Perform a uniform scan.

[0047] During the printing process, the print head 1 emits laser light 4 to the Y-axis galvanometer 2, and the Y-axis galvanometer 2 reflects the laser light to the X-axis galvanometer 3, causing the laser light to scan along the Y-axis direction on the X-axis galvanometer. The scanning velocity vector is The X-axis galvanometer reflects the laser toward the printing work surface and makes the laser scan along the X-axis direction on the printing work surface 4. The scanning velocity vector is From this we can see that the galvanometer scanning velocity vector The scanning velocity vector of the Y-axis galvanometer along the Y-axis direction and the velocity vector of the X-axis galvanometer along the X-axis direction on the printing work surface 4 Therefore, the scanning velocity vector and the scanning velocity vector Satisfy the requirements of formula (2):

[0048]

[0049] According to the scanning speed vector of the Y-axis galvanometer along the Y-axis direction and the velocity vector of the X-axis galvanometer along the X-axis direction on the printing work surface 4 It can be further converted into the rotational angular velocity of the X-axis galvanometer and the Y-axis galvanometer. The formula for the rotational angular velocity of the X-axis galvanometer and the Y-axis galvanometer is:

[0050]

[0051]

[0052] In the formula, D is the distance between the X-axis galvanometer and the Y-axis galvanometer, L is the vertical distance from the Y-axis galvanometer to the printing work surface, x is the horizontal coordinate of the current scanning position, y is the vertical coordinate of the current scanning position, V x and V y are the velocity components of the scanning velocity V in the x and y directions, that is, the scanning velocity vector is The magnitude and scanning velocity vector are The size of ω y is the scanning angular velocity of the Y-axis galvanometer pair, ω x is the scanning angular velocity of the X-axis galvanometer pair.

[0053] Therefore, this step only needs to control the rotation angular velocity of the X-axis galvanometer and the Y-axis galvanometer to convert the scanning speed vector of the document to be printed into Converted into galvanometer scanning velocity vector like Figure 5 As shown, the scanning of the file to be printed can be achieved by allowing the galvanometer to move uniformly in any form on the printing plane, and through the transformation relationship, the position and speed required for printing the work surface pattern are converted into the scanning speed and position of the galvanometer motor in the moving galvanometer platform. During the entire printing process, the print head, X-axis galvanometer and Y-axis galvanometer are all moved at a horizontal speed vector Maintaining a uniform speed reduces the acceleration and deceleration time of the galvanometer module, resulting in higher printing efficiency.

[0054] Example 2

[0055] The laser 3D printing mobile scanning device involved in this embodiment includes multiple groups of scanning mechanisms, that is, multiple print heads are set, and the multiple print heads are arranged side by side. Each print head 1 is equipped with a Y-axis galvanometer 2 and an X-axis galvanometer 3. The structure of each group of scanning mechanisms is the same as that of Example 1, and will not be elaborated in this embodiment. The horizontal movement speed vector of each print head is same.

[0056] For the use of large-format 3D printers, existing scanning methods such as Figure 6 As shown, since the printing format of each galvanometer print head is very small, usually no more than 350*350mm, to achieve printing format of more than 1 meter, the galvanometer print head can only be used as follows Figure 6 The array arrangement shown is arranged in an array manner. During printing, the galvanometers arranged in an array manner cannot avoid the mutual interference of smoke and dust, which will seriously affect the printing quality. Since the printing format of each galvanometer print head is limited, this shortcoming cannot be avoided.

[0057] The laser 3D printing mobile scanning device involved in this embodiment is used, such as Figure 7 As shown in the figure, multiple laser print heads are arranged in a row and perform translational scanning along one direction. The multiple laser heads can perfectly avoid the smoke problem, so that large-format printing is not disturbed by smoke, which is of great significance to large-format 3D printing.

[0058] The present invention has been described in detail above with reference to the embodiments. However, the contents described are only preferred embodiments of the present invention and should not be considered as limiting the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A laser 3D printing mobile scanning method, characterized by: It includes the following steps: S1. Input the file to be printed and set the scanning speed vector of the file to be printed ; S2. Set the print head horizontal speed vector ; S3. Scan the document to be printed according to the speed vector and the print head horizontal velocity vector , calculate the galvanometer scanning velocity vector , so that the galvanometer scanning velocity vector and the print head horizontal movement velocity vector After superposition, the scanning speed vector of the document to be printed same; S4. Start scanning, the print head, X-axis galvanometer and Y-axis galvanometer move horizontally at a speed vector Maintaining uniform motion, the X-axis galvanometer and the Y-axis galvanometer are rotated by the motor at the same time, so that the laser emitted by the print head is reflected by the X-axis galvanometer and the Y-axis galvanometer and then moves on the printing work surface at the galvanometer scanning speed vector Perform uniform scanning, and the formula for the rotational angular velocity of the X-axis galvanometer and the Y-axis galvanometer is: （1） （2） In the formula, D is the distance between the X-axis galvanometer and the Y-axis galvanometer, L is the vertical distance from the Y-axis galvanometer to the printing work surface, x is the horizontal coordinate of the current scanning position, y is the ordinate of the current scanning position, V x and V y Scan speed V exist x 、 y The velocity component in the direction, that is, the scanning velocity vector is The magnitude and scanning velocity vector are The size of is the scanning angular velocity of the Y-axis galvanometer pair, is the scanning angular velocity of the X-axis galvanometer pair.

2. The laser 3D printing mobile scanning method according to claim 1, characterized in that: The step S3 calculates the scanning velocity vector of the galvanometer The calculation formula is: （1）。 3. The laser 3D printing mobile scanning method according to claim 1, characterized in that: In step S4, the print head emits laser light to the Y-axis galvanometer, and the Y-axis galvanometer reflects the laser light to the X-axis galvanometer, so that the laser light scans along the Y-axis direction on the X-axis galvanometer. The scanning velocity vector is The X-axis galvanometer reflects the laser to the printing work surface and makes the laser scan along the X-axis direction on the printing work surface. The scanning velocity vector is ; Scan velocity vector and the scanning velocity vector Satisfy the requirements of formula (2): （2）。 4. The laser 3D printing mobile scanning method according to claim 1, characterized in that: The print heads are arranged in a plurality, and the plurality of print heads are arranged side by side, and the horizontal speed vector of each print head is same.

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