3D printing equipment galvanometer point calibration device and 3D printing equipment galvanometer point calibration method

Abstract

The invention relates to the field of 3D printing, aims to solve the problem that a known 3D printing equipment calibration scheme is low in efficiency or high in labor cost, and provides a 3D printing equipment galvanometer point calibration device and method. The galvanometer point calibration device for the 3D printing equipment comprises a calibration plate and a photoelectric sensor, the calibration plate is provided with a first surface and a second surface which are opposite; the calibration plate is provided with a plurality of calibration holes distributed on the surface; the aperture of the calibration hole is larger than the diameter of a laser spot and smaller than 1.5 times of the diameter of the laser spot; the calibration hole corresponds to the photoelectric sensor; the hole surface of the calibration hole is a reflecting surface, and is used for reflecting laser which is controlled by the galvanometer to exit and is incident from the calibration hole for one or more times and then transmitting the laser to the photoelectric sensor; the photoelectric sensor can detect the intensity of light entering the photoelectric sensor, and the light intensity is used for judging the amount of laser entering the calibration holes, so that the position relation between laser spots irradiated on the calibration plate and the corresponding calibration holes is judged. The method has the advantages of being high in efficiency and low in labor cost.

Description

Technical Field

[0001] The present application relates to the field of 3D printing, and more specifically, to a 3D printing device galvanometer point calibration device and a 3D printing device galvanometer point calibration method. Background Art

[0002] When the galvanometer of a known 3D printing device is calibrated at a point, an optical measuring instrument such as a second element is required. During the calibration process, the marking paper needs to be transferred from the device printing cabin to the optical measuring device multiple times. In addition, the readings of the optical measuring instrument are subject to human subjective interference, and the operator needs to have professional data statistical measurement knowledge. After each measurement, the corrected data is obtained, and it is necessary to reprint and repeat the optical measurement verification, which has high labor costs and low efficiency.

[0003] The method of using a high-precision camera for online reading is essentially to replace the optical measuring instrument with the camera. However, the high-precision camera needs to be calibrated for lens distortion and then calibrated for size before it can be used. In addition, the characteristics of the camera will inevitably cause pixel drift and theoretical resolution lower than actual resolution. The measured data will be slightly worse than that of measuring instruments such as the second dimension. It also requires professional operation to achieve good results. There are also problems of low efficiency or high labor costs. Summary of the invention

[0004] The present application provides a 3D printing device galvanometer point calibration device and a 3D printing device galvanometer point calibration method to solve the problem of low efficiency or high labor cost of known 3D printing device calibration solutions.

[0005] In a first aspect, the present application provides a 3D printing device galvanometer point calibration device, wherein the galvanometer can be controlled to move to control the irradiation position of the laser emitted by the 3D printing device, and the 3D printing device galvanometer point calibration device includes a calibration plate and a photoelectric sensor;

[0006] The calibration plate has a first surface and a second surface opposite to each other, the galvanometer is located on one side of the first surface, and the photoelectric sensor is located on one side of the second surface;

[0007] The calibration plate is provided with a plurality of calibration holes distributed on the surface, and the calibration holes penetrate the first surface and the second surface of the calibration plate; the aperture of the calibration holes is larger than the laser spot diameter and smaller than 1.5 times of the laser spot diameter;

[0008] The calibration hole corresponds to the photoelectric sensor;

[0009] The hole surface of the calibration hole is a reflective surface, which is used to reflect the laser light emitted by the galvanometer and incident from the calibration hole once or multiple times and then transmit it to the photoelectric sensor;

[0010] The photoelectric sensor can detect the intensity of light incident on it. The light intensity is used to determine the amount of laser entering the calibration hole, and then determine the positional relationship between the laser spot irradiated on the calibration plate and the corresponding calibration hole. The positional relationship is used to calibrate the galvanometer.

[0011] In the 3D printing device galvanometer point calibration device in the present application, each calibration hole can be used as a calibration point, and the complete calibration of the galvanometer can be completed by calibrating multiple calibration holes distributed on the surface.

[0012] When calibrating a calibration hole, the galvanometer of the 3D printing device is controlled to deflect to the corresponding angle, and the laser emitted by the 3D printing device is reflected by the galvanometer at the deflection angle and irradiated near the calibration hole of the calibration plate. Due to the uncertainty of the galvanometer error, the actual irradiation position of the laser may correspond to the calibration hole or may be around the calibration hole;

[0013] If the light spot irradiated on the calibration plate falls entirely within the range of the calibration hole, all the light will enter the calibration hole and be reflected by the hole surface of the calibration hole and transmitted to the photoelectric sensor, and the light intensity detected by the photoelectric sensor is the largest; if only part of the light spot irradiated on the calibration plate falls within the range of the calibration hole, only part of the light will enter the calibration hole and be reflected by the hole surface of the calibration hole and transmitted to the photoelectric sensor, while the rest of the light will be absorbed by the first surface or reflected elsewhere; at this time, the light intensity detected by the photoelectric sensor is relatively small. That is, the farther the irradiation position of the laser light spot deviates from the center of the calibration hole, the less light will enter the calibration hole, and the corresponding light intensity detected will also be smaller;

[0014] In this way, the amount of laser light entering the calibration hole can be determined by the light intensity detected by the photoelectric sensor, and then the positional relationship between the laser spot irradiation position and the corresponding calibration hole can be determined. This positional relationship can be used to calibrate the galvanometer.

[0015] In one possible implementation:

[0016] The laser spot is a circular spot with a diameter of 4 μm, and the calibration hole is a circular hole with a diameter of 5 μm;

[0017] The calibration hole is an elongated hole with a ratio of hole depth to hole diameter greater than 100.

[0018] In one possible implementation:

[0019] The calibration plate is made of stainless steel, and the reflectivity of the hole surface is greater than 85% and less than 90%.

[0020] In one possible implementation:

[0021] The 3D printing device galvanometer point calibration device also includes a plurality of optical fibers;

[0022] The plurality of optical fibers are respectively connected to the plurality of calibration holes; one end of the optical fiber is connected to the calibration hole close to the second surface, and the other end is connected to the photoelectric sensor.

[0023] In one possible implementation:

[0024] The 3D printing equipment galvanometer point calibration device also includes a closed chamber, which is connected to one side of the second surface of the calibration plate and forms a light-shielding space with the closed chamber;

[0025] The photoelectric sensor and optical fiber are located in the light-shielded space.

[0026] In one possible implementation:

[0027] The galvanometer is controlled to rotate by a galvanometer driver. The calibration device also includes a control device, which is electrically connected to the photoelectric sensor and the galvanometer driver, and is used to receive the light intensity detected by the photoelectric sensor;

[0028] The galvanometer driver is used to control the galvanometer to rotate within a certain range, so that the laser spot scans within a certain range around the selected calibration hole until the light intensity detected by the photoelectric sensor reaches a maximum value;

[0029] When the light intensity detected by the photoelectric sensor reaches a maximum value, the angle value of the galvanometer is used as the calibrated angle value of the position of the calibration hole corresponding to the galvanometer.

[0030] In one possible implementation:

[0031] The calibration board is divided into multiple partitions;

[0032] There are multiple galvanometers, and each of the multiple galvanometers corresponds to a plurality of partitions;

[0033] Adjacent subareas have overlapping areas, and the overlapping areas have at least one calibration hole.

[0034] In one possible implementation:

[0035] The overlap area is in the shape of a cross, and has a plurality of calibration holes distributed in the shape of a cross.

[0036] In a second aspect, the present application provides a 3D printing device galvanometer point calibration method, which is based on the aforementioned 3D printing device galvanometer point calibration device, and the 3D printing device galvanometer point calibration method includes:

[0037] Select a calibration hole. The position of the calibration hole is the theoretical point of the galvanometer. The theoretical point of the galvanometer refers to the theoretical irradiation point of the laser spot when the galvanometer rotates at a set angle.

[0038] The galvanometer is controlled to rotate to a set rotation angle, and rotates within a certain range near the set rotation angle; during rotation, the incident light intensity is detected by a photoelectric sensor; when the light intensity reaches a set maximum value, the rotation angle value of the position of the galvanometer is corrected to the set rotation angle corresponding to the theoretical point of the galvanometer;

[0039] Select other calibration holes in turn and repeat the above calibration until all calibration holes or some of the required calibration holes are calibrated.

[0040] In one possible implementation:

[0041] Dividing the calibration plate into a plurality of partitions, wherein adjacent partitions have overlapping areas, and the overlapping areas include a plurality of calibration holes distributed in a cross shape;

[0042] There are multiple galvanometers, and the multiple galvanometers correspond to multiple partitions respectively. The adjacent galvanometers are calibrated respectively through the calibration holes in the overlapping area to achieve point splicing of the multiple galvanometers. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0044] Figure 1 A schematic diagram of the structure of a galvanometer point calibration device for a 3D printing device according to an embodiment of the present application is shown in FIG.

[0045] Figure 2 for Figure 1 A partial cross-sectional view from another perspective;

[0046] Figure 3 A schematic structural diagram of a galvanometer point calibration device for a 3D printing device according to another embodiment of the present application is shown in FIG.

[0047] Description of main component symbols:

[0048] 3D printing equipment 100

[0049] Galvanometer 101

[0050] Galvanometer driver 102

[0051] Laser L1

[0052] Divider line L3

[0053] 3D printing equipment galvanometer point calibration device 10

[0054] Calibration board 11

[0055] Photoelectric sensor 12

[0056] Fiber 13

[0057] Closed room 14

[0058] Control device 30

[0059] Calibration hole K1

[0060] First surface P1

[0061] Second surface P2

[0062] Hole surface P3

[0063] Shading space Q1

[0064] Partitions S1, S2

[0065] Overlap area S3 DETAILED DESCRIPTION

[0066] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0067] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may also be a centered element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may also be a centered element. When an element is considered to be "set on" another element, it may be directly set on the other element or there may also be a centered element. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0068] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present application. The terms used herein in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. The term "or / and" used herein includes any and all combinations of one or more related listed items.

[0069] Some embodiments of the present application are described in detail. In the absence of conflict, the following embodiments and features of the embodiments can be combined with each other.

[0070] 3D printing equipment (such as SLM metal 3D printing equipment) mainly controls the laser emitted by the laser through optical devices such as galvanometers to irradiate the powder material (such as metal powder) in the printing area along a set scanning path. The powder material in the laser irradiated area receives the laser energy and fuses to form a solid.

[0071] In order to ensure that the laser is accurately irradiated on the scanning path, it is necessary to ensure that the galvanometer has a high control accuracy, that is, there is a relatively accurate correspondence between the rotation angle of the galvanometer and the corresponding irradiation position.

[0072] Taking a two-dimensional galvanometer as an example, under ideal conditions, the functional relationship between the coordinates (x, y) of a point P on the scanning path on the printing surface and the two-dimensional rotation angle value (α, β) of the galvanometer is (x, y) = F(α, β), that is, when the two-dimensional rotation angle values ​​of the galvanometer are α and β respectively, the coordinates of the position of the light spot formed by the laser being reflected by the galvanometer onto the printing surface are (x, y).

[0073] Thus, when the laser is required to irradiate a point D1(x1,y1) on the set scanning path, the corresponding angle value can be obtained by inversely calculating the above function, and (α1,β1)=F -1 In this way, by controlling the galvanometer control device 30 to rotate the galvanometer at an angle (α1, β1), the light spot can be irradiated at the desired coordinate position (x1, y1).

[0074] However, due to the relative position offset or structural deformation of the components during use, when the galvanometer rotates to a certain angle, such as (α1, β1), the actual irradiation position of the laser spot deviates from the theoretical coordinate position (x1, y1), thereby affecting the printing accuracy.

[0075] The 3D printing device galvanometer point calibration device and the 3D printing device galvanometer point calibration method provided in this embodiment can accurately calibrate the galvanometer so that the rotation angle of the galvanometer and the laser irradiation position after calibration are more accurately corresponding to ensure the accuracy of the printed part, which will be explained exemplarily below.

[0076] Example

[0077] See also Figure 1 and Figure 2 This embodiment provides a 3D printing device galvanometer point calibration device 10 , wherein the galvanometer 101 can be controlled to rotate by a galvanometer driver 102 to control the irradiation position of the laser L1 emitted by the 3D printing device 100 .

[0078] The 3D printing device galvanometer point calibration device 10 comprises a calibration plate 11, a photoelectric sensor 12 and a plurality of optical fibers 13. The photoelectric sensor 12 may be a light intensity sensor or other sensors based on the photoelectric effect.

[0079] The calibration plate 11 has a first surface P1 and a second surface P2 that are opposite to each other. The galvanometer 101 is located on one side of the first surface P1 , and the photoelectric sensor 12 is located on one side of the second surface P2 .

[0080] The calibration plate 11 is provided with a plurality of calibration holes K1 distributed on the surface. The plurality of calibration holes K1 may be distributed in the form of a matrix distribution or in the form of multiple inner and outer circular distributions, which is not limited here.

[0081] The calibration hole K1 is a through hole, and the calibration hole K1 passes through the first surface P1 and the second surface P2 of the calibration plate 11. The aperture of the calibration hole K1 is larger than the spot diameter of the laser L1 and smaller than 1.5 times the spot diameter of the laser L1. For example, in one embodiment, the spot of the laser L1 is a circular spot with a diameter of 4 μm, and the calibration hole K1 is a circular hole with a diameter of 5 μm, and the aperture of the calibration hole K1 is slightly larger than the spot of the laser L1.

[0082] It should be noted that in order to ensure that the spot shape of the laser L1 irradiated onto the printing surface or the first surface P1 of the calibration plate 11 from different angles remains circular, a common light modulation scheme (such as modulation by optical elements such as field lenses and collimators) can be adopted, which will not be elaborated here.

[0083] The plurality of optical fibers 13 are respectively connected to the plurality of calibration holes K1. Specifically, one end of the optical fiber 13 is connected to the side of the calibration hole K1 close to the second surface P2, and the other end corresponds to the photoelectric sensor 12. Optionally, one end of the optical fiber 13 is inserted into the portion of the calibration hole K1 close to the second surface P2 and is glued to the second surface P2. In this way, the laser L1 entering the calibration hole K1 can be transmitted into the optical fiber 13. It should be noted that Figure 2 Only one calibration hole K1 and one optical fiber 13 are shown as an illustration, and other calibration holes K1 and optical fibers 13 are not shown.

[0084] The hole surface P3 of the calibration hole K1 is a reflective surface for reflecting the laser light L1 controlled to be emitted by the galvanometer 101 and incident from the calibration hole K1 once or multiple times to enter the optical fiber 13 and be transmitted to the photoelectric sensor 12 by the optical fiber 13 .

[0085] The reflective surface here refers to a surface with a high light reflectivity, such as a surface with a reflectivity of more than 85%. By setting the hole surface P3 as a reflective surface, the laser L1 incident into the calibration hole K1 can be reflected by the hole surface P3 to the optical fiber 13, and then detected by the photoelectric sensor 12.

[0086] Optionally, the calibration hole K1 can be formed by a high-speed rotary head and then processed by fluid grinding, so that the hole surface P3 forms a smooth reflective surface.

[0087] The photoelectric sensor 12 can detect the intensity of light incident thereon, and the light intensity is used to determine the amount of laser L1 entering the calibration hole K1, and further determine the positional relationship between the laser L1 spot irradiated on the calibration plate 11 and the corresponding calibration hole K1. The positional relationship is used to calibrate the galvanometer 101.

[0088] In the 3D printing device galvanometer point calibration device 10 in this embodiment, each calibration hole K1 can be used as a calibration point, and the galvanometer 101 can be completely calibrated by calibrating multiple calibration holes K1 distributed on the surface.

[0089] When calibrating a calibration hole K1, the galvanometer 101 of the 3D printing device 100 is controlled to deflect to a corresponding angle, and the laser L1 emitted by the 3D printing device 100 is reflected by the galvanometer 101 at the deflection angle and irradiates near the calibration hole K1 of the calibration plate 11. Due to the uncertainty of the error of the galvanometer 101, the actual irradiation position of the laser L1 may correspond to the calibration hole K1, or may be around the calibration hole K1;

[0090] If the light spot irradiated on the calibration plate 11 falls entirely within the range of the calibration hole K1, all the light will enter the calibration hole K1 and be reflected by the hole surface P3 of the calibration hole K1 into the optical fiber 13, and be transmitted from the optical fiber 13 to the photoelectric sensor 12, and the light intensity detected by the photoelectric sensor 12 is the largest; if only part of the light spot irradiated on the calibration plate 11 falls entirely within the range of the calibration hole K1, only part of the light will enter the calibration hole K1 and be reflected by the hole surface P3 of the calibration hole K1 into the optical fiber 13, and be transmitted from the optical fiber 13 to the photoelectric sensor 12, while the rest of the light will be absorbed by the first surface P1 or reflected elsewhere; at this time, the light intensity detected by the photoelectric sensor 12 is relatively small. That is, the farther the irradiation position of the laser L1 light spot deviates from the center of the calibration hole K1, the less light will enter the calibration hole K1, and the corresponding light intensity detected will also be smaller;

[0091] In this way, the amount of laser light L1 entering the calibration hole K1 can be determined by the light intensity detected by the photoelectric sensor 12 , and the positional relationship between the irradiation position of the laser light spot L1 and the corresponding calibration hole K1 can be determined. This positional relationship can be used to calibrate the galvanometer 101 .

[0092] It was found in the test that when the space between the first surface P1 of the calibration hole K1 and the galvanometer 101 was treated in a darkroom, the point calibration accuracy of the galvanometer point calibration device 10 of the 3D printing device in this embodiment was improved to a certain extent. This may be because when the reflectivity of the hole surface P3 is extremely high, if the darkroom treatment is not performed, the stray light (ambient light or light generated by other light sources) on one side of the first surface P1 will also be reflected through the hole surface P3 and enter the optical fiber 13, and then be sensed by the photoelectric sensor 12, thereby affecting the measurement result. In the real test environment, it is time-consuming and labor-intensive to perform darkroom treatment between the first surface P1 and the galvanometer 101, and the cost is relatively high.

[0093] This embodiment increases the number of reflections of the laser L1 on the hole surface P3 by setting a larger depth-to-aperture ratio of the calibration hole K1, and reduces its influence on the detection result by appropriately limiting the reflectivity of the hole surface P3 so that the stray light entering the calibration hole K1 is greatly lost.

[0094] For example, in one embodiment, the reflectivity of the hole surface P3 is limited to below 90% (specifically between 85% and 90%), and the calibration hole K1 is set to be an elongated hole with a ratio of hole depth to hole diameter greater than 100. This can greatly reduce the impact of stray light on the detection results and obtain higher detection accuracy.

[0095] In this embodiment, the calibration plate 11 can be made of stainless steel, and the hole surface P3 can achieve a reflectivity of 85%-90% through polishing or other methods.

[0096] In this embodiment, optionally, the 3D printing device galvanometer point calibration device 10 further includes a closed chamber 14, which is connected to one side of the second surface P2 of the calibration plate 11 and forms a light-shielding space Q1 with the closed chamber 14. The photoelectric sensor 12 and the optical fiber 13 are located in the light-shielding space Q1 to avoid detection errors caused by external light directly shining on the photoelectric sensor 12.

[0097] In another embodiment, the optical fiber 13 may not be provided, but the calibration hole K1 may directly correspond to the photoelectric sensor 12 so that the light reflected from the hole surface P3 of the calibration hole K1 directly irradiates the photoelectric sensor 12 .

[0098] The 3D printing device galvanometer point calibration device 10 also includes a control device 30, which is electrically connected to the photoelectric sensor 12 and the galvanometer driver 102, and the control device 30 is used to receive the light intensity detected by the photoelectric sensor 12. The galvanometer driver 102 is used to control the galvanometer 101 to rotate within a certain range, so that the spot of the laser L1 scans within a certain range around the selected calibration hole K1 until the light intensity detected by the photoelectric sensor 12 reaches a maximum value. When the light intensity detected by the photoelectric sensor 12 reaches a maximum value, the angle value of the galvanometer 101 is used as the calibrated angle value of the position of the calibration hole K1 corresponding to the galvanometer 101.

[0099] See also Figure 3 In one embodiment, the calibration plate 11 is divided into a plurality of partitions, and there are a plurality of galvanometers 101, and the plurality of galvanometers 101 correspond to the plurality of partitions. For example, as shown in the figure, there are two partitions, which are marked as partition S1 and partition S2. Figure 3 The dividing line L3 shown is used as a boundary line. There are two corresponding galvanometer mirrors 101 .

[0100] Partition S1 and partition S2 have an overlap area S3, and at least one calibration hole K1 is provided in the overlap area S3. The two galvanometer mirrors 101 are point-calibrated respectively through the calibration hole K1 in the overlap area S3, so that the printing paths of the two galvanometer mirrors 101 can be spliced, that is, the point splicing of the two galvanometer mirrors 101 is completed.

[0101] Optionally, the overlap area S3 is in the shape of a cross, and has a plurality of calibration holes K1 distributed in a cross shape in the overlap area S3. The plurality of calibration holes K1 distributed in a cross shape calibrate the two galvanometers 101 respectively, which is beneficial to improve the point splicing accuracy of the galvanometer 101 in two directions.

[0102] The embodiment of the present application further provides a 3D printing device galvanometer point calibration method, which is based on the aforementioned 3D printing device galvanometer point calibration device 10, and the 3D printing device galvanometer point calibration method includes:

[0103] A calibration hole K1 is selected. The position of the calibration hole K1 is the theoretical position of the galvanometer. The theoretical position of the galvanometer refers to the theoretical irradiation point of the laser L1 spot when the galvanometer 101 rotates at a set angle.

[0104] The galvanometer 101 is controlled to rotate to a set rotation angle, and the galvanometer 101 rotates within a certain range near the set rotation angle; during the rotation, the incident light intensity is detected by the photoelectric sensor 12; when the light intensity reaches a set maximum value, the rotation angle value of the position of the galvanometer 101 is corrected to the set rotation angle corresponding to the theoretical point position of the galvanometer 101;

[0105] Other calibration holes K1 are selected in turn to repeat the above calibration until the calibration of all calibration holes K1 or a required portion of calibration holes K1 is completed.

[0106] Alternatively, if Figure 3 As shown, the calibration plate 11 is divided into a plurality of partitions (such as partition S1 and partition S2), and adjacent partitions have an overlap area S3, and the overlap area S3 includes a plurality of calibration holes K1 distributed in a cross shape;

[0107] There are multiple galvanometer mirrors 101 , and the multiple galvanometer mirrors 101 correspond to multiple partitions respectively. The adjacent galvanometer mirrors 101 are calibrated respectively through the calibration holes K1 in the overlap area S3 to achieve point splicing of the multiple galvanometer mirrors 101 .

[0108] When printing, the printing paths of the multiple galvanometer mirrors 101 after point splicing can be spliced ​​with high precision, which is beneficial to improving the point splicing precision when the multiple galvanometer mirrors 101 are spliced ​​and printed.

[0109] Therefore, by using the 3D printing device galvanometer point calibration device 10 in the embodiment of the present application, the galvanometer 101 can be accurately calibrated or stitched, and the calibration accuracy can reach 0.02mm. In addition, the calibration device and calibration method can be fully operated online, without leaving the device printing cabin, without the need to use measuring instruments such as secondary elements, etc., the operation is simple, labor costs are saved, and the detection accuracy is reliable, avoiding the influence of human factors.

[0110] Taking the printing range of 650mm*650mm format of four galvanometers as an example, using the conventional two-dimensional measurement method, it is necessary to repeat the measurement three times, each time taking 2 hours, with a calibration accuracy of 0.03mm, and technicians need to participate in the whole process;

[0111] When using the 3D printing equipment galvanometer point calibration device 10 of the present application, it takes 1 hour to complete a scan, and the calibration accuracy is 0.02mm. There is no need for personnel to participate in the whole process. You only need to connect the equipment and start the program to complete it automatically.

[0112] Furthermore, the calibration plate 11 is completed by high-precision machining adopted in this embodiment, and the existing machining level meets the machining requirements, and the cost is much lower than that of optical measuring instruments such as the second dimension.

[0113] The 3D printing equipment galvanometer point calibration device 10 of this embodiment is small in size, easy to carry, and plug-and-play. Other similar measurement devices are large instruments that need to be placed in a specific place for use.

[0114] The above implementation modes are only used to illustrate the technical solutions of the present application and are not intended to limit the present application. Although the present application has been described in detail with reference to the above preferred implementation modes, a person skilled in the art should understand that the technical solutions of the present application may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present application.

Claims

1. A 3D printing device galvanometer point calibration device, wherein the galvanometer can be controlled to control the irradiation position of the laser emitted by the 3D printing device, characterized in that: The 3D printing equipment galvanometer point calibration device includes a calibration plate and a photoelectric sensor; The calibration plate has a first surface and a second surface opposite to each other, the galvanometer is located on one side of the first surface, and the photoelectric sensor is located on one side of the second surface; The calibration plate is provided with a plurality of calibration holes distributed on the surface, and the calibration holes penetrate the first surface and the second surface of the calibration plate; the aperture of the calibration hole is larger than the diameter of the laser spot and smaller than 1.5 times of the diameter of the laser spot; The calibration hole corresponds to the photoelectric sensor; The hole surface of the calibration hole is a reflective surface, which is used to reflect the laser light emitted by the galvanometer and incident from the calibration hole once or multiple times and then transmit it to the photoelectric sensor; The photoelectric sensor can detect the intensity of light incident thereon, and the intensity of light is used to determine the amount of laser light entering the calibration hole, and further determine the positional relationship between the laser spot irradiated on the calibration plate and the corresponding calibration hole, and the positional relationship is used to calibrate the galvanometer.

2. The 3D printing equipment galvanometer point calibration device according to claim 1, characterized in that: The laser spot is a circular spot with a diameter of 4 μm, and the calibration hole is a circular hole with a diameter of 5 μm; The calibration hole is an elongated hole with a ratio of hole depth to hole diameter greater than 100.

3. The 3D printing equipment galvanometer point calibration device according to claim 1, characterized in that: The calibration plate is made of stainless steel, and the reflectivity of the hole surface is greater than 85% and less than 90%.

4. The 3D printing equipment galvanometer point calibration device according to claim 1, characterized in that: The 3D printing equipment galvanometer point calibration device also includes a plurality of optical fibers; The plurality of optical fibers are respectively connected to the plurality of calibration holes; one end of the optical fiber is connected to the calibration hole close to the second surface, and the other end corresponds to the photoelectric sensor.

5. The 3D printing equipment galvanometer point calibration device according to claim 4, characterized in that: The 3D printing equipment galvanometer point calibration device further includes a closed chamber, which is connected to one side of the second surface of the calibration plate and forms a light-shielding space with the closed chamber; The photoelectric sensor and the optical fiber are located in the light-shielding space.

6. The 3D printing equipment galvanometer point calibration device according to claim 1, characterized in that: The galvanometer is controlled to rotate by a galvanometer driver, and the calibration device further comprises a control device, the control device is electrically connected to the photoelectric sensor and the galvanometer driver, and the control device is used to receive the light intensity detected by the photoelectric sensor; The galvanometer driver is used to control the galvanometer to rotate within a certain range, so that the laser spot scans within a certain range around the selected calibration hole until the light intensity detected by the photoelectric sensor reaches a maximum value; When the light intensity detected by the photoelectric sensor reaches a maximum value, the angle value of the galvanometer is used as the calibrated angle value of the position of the calibration hole corresponding to the galvanometer.

7. The galvanometer point calibration device for 3D printing equipment according to any one of claims 1 to 6, characterized in that: The calibration plate is divided into a plurality of partitions; There are multiple galvanometers, and the multiple galvanometers correspond to the multiple partitions respectively; Adjacent partitions have overlapping areas, and the overlapping areas have at least one calibration hole.

8. The 3D printing equipment galvanometer point calibration device according to claim 7, characterized in that: The overlap area is in the shape of a cross, and has a plurality of calibration holes distributed in the shape of a cross.

9. A 3D printing device galvanometer point calibration method, characterized in that: Based on the 3D printing device galvanometer point calibration device according to any one of claims 1 to 8, the 3D printing device galvanometer point calibration method comprises: A calibration hole is selected, the position of the calibration hole is the theoretical point position of the galvanometer, and the theoretical point position of the galvanometer refers to the point position of the theoretical irradiation of the laser spot when the galvanometer rotates at a set angle; The galvanometer is controlled to rotate to the set rotation angle, and is made to rotate within a certain range near the set rotation angle; during the rotation, the incident light intensity is detected by the photoelectric sensor; when the light intensity reaches a set maximum value, the rotation angle value of the position of the galvanometer is corrected to the set rotation angle corresponding to the theoretical point position of the galvanometer; Select other calibration holes in turn and repeat the above calibration until all calibration holes or some of the required calibration holes are calibrated.

10. The 3D printing device galvanometer point calibration method according to claim 9, characterized in that: Dividing the calibration plate into a plurality of partitions, wherein adjacent partitions have overlapping areas, and the overlapping areas include a plurality of calibration holes distributed in a cross shape; There are multiple galvanometers, and the multiple galvanometers correspond to the multiple partitions respectively. The adjacent galvanometers are calibrated respectively through the calibration holes in the overlapping area to achieve point splicing of the multiple galvanometers.

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