KR102354398B1 - Method for determining whether correction is required of an optical system of 3D printer - Google Patents

Abstract

The present invention relates to a method for determining whether an optical system of a 3D printer needs to be calibrated and, specifically, in a method for determining whether an optical system of a 3D printer to which optical system is applied needs to be calibrated, to a method for determining whether an optical system applied to a 3D printer needs to be calibrated by including: a step of preparing an inspection paper; a step of positioning the inspection paper on the output surface of a reference 3D printer; a step of emitting a reference pattern on the inspection paper with the reference 3D printer; a step of positioning the inspection paper irradiated with the reference pattern on the output surface of an inspection 3D printer to determine whether calibration is necessary; a step of emitting an inspection pattern on the inspection paper with the inspection 3D printer; and a step of determining whether an optical system of the inspection 3D printer needs to be calibrated by comparing the inspection pattern with the reference pattern emitted on the inspection paper. Therefore, the time and cost required for determining whether the optical system needs to be calibrated can be reduced compared to the prior art.

Description

Method for determining whether correction is required of an optical system of 3D printer

The present invention relates to a method for determining whether correction of an optical system applied to a 3D printer is necessary.

In general, 3D printers are divided into stacked 3D printers, which stack materials layer by layer, and print 3D printers, which cut and print large chunks of material.

1 shows a schematic structure of a 3D printer having a conventional optical system of a selective laser melting (SLM) method, which is a type of a multilayer 3D printer. The 3D printer is an output that may include a laser 20, a scanner 30 that is an optical system that changes the traveling direction of the laser supplied from the feeder 20 in a desired direction, and a molding plate (not shown). It may be composed of a cotton 60, a hopper 40 for supplying a material to the molding plate, and a recoater 50 for coating the material supplied from the hopper 40. As a related technology, there is a technology such as Korean Patent Application Laid-Open No. 10-2018-0130037 (patent document).

In such a 3D printer, the position of the optical system may be changed due to transportation, vibration, etc., and thus the set value of the configuration may not match the actual value. Therefore, these 3D printers must determine whether the optical system needs to be calibrated before printing.

There are the following methods as a general correction process for determining whether correction is necessary or not.

First, a CCP (high gloss printing paper) printed with black ink is placed on the output surface, and a grid pattern at regular intervals is irradiated on the paper with a laser. Thereafter, the paper on which the grid pattern is marked is scanned with a 2D optical scanner, or the pattern image output through vision (cam) is converted back into a digital image. Thereafter, the original image of the pattern and the digital image are compared, but at this time, as shown in FIG. 6( a ), XY coordinates for each position of the pattern, that is, the part marked with + is compared. As a result of the comparison, as shown in Fig. 6(b), the larger the arrow shown in the XY coordinates for each position, the greater the error, which means that the corresponding XY coordinates need to be corrected. In this way, if the error of the corresponding XY coordinates is greater than or equal to the threshold, the correction value is applied to the corresponding XY coordinates of the pattern using the correction software, and the correction is returned to the first step to determine whether correction is necessary. These processes are repeated until the error of the XY coordinates for each location falls within the threshold. Meanwhile, in FIG. 6 , the X direction is indicated by an arrow in the 12 o'clock direction, and the Y direction is indicated by an arrow in the 3 o'clock direction.

In the prior art described above, when the CCP paper on which the pattern is marked is scanned and converted into a digital image, the result may be different from the actual result depending on the precision of the scan printer.

In addition, it takes a lot of time until the process of determining whether the above-described correction is necessary.

In addition, since it is difficult for ordinary people to judge small errors, specialized technical personnel and specialized tools are required.

In addition, the 2D scanner or the vision (cam) is required separately from the 3D printer.

Due to the above reasons, the prior art increases the cost and time for using a 3D printer.

Korean Patent Publication No. 10-2018-0130037 (2018.12.06)

An object of the present invention is to solve the above problem, and an object of the present invention is to provide a method for simply determining whether correction of an optical system applied to a 3D printer is necessary.

In addition, an object of the present invention is to provide a method by which a non-specialist can determine whether correction of the optical system of a 3D printer is necessary without a specialized tool.

In addition, an object of the present invention is to provide a method for determining whether or not correction of the optical system of a 3D printer capable of visually confirming the inspection result of the inspection pattern is required.

The method for determining whether correction of an optical system of a 3D printer of the present invention for achieving the above object is necessary is a method for determining whether correction of an optical system of a 3D printer to which an optical system is applied, the method comprising: preparing an inspection paper; positioning the test paper in a reference 3D printer; irradiating a reference pattern on the inspection paper with the reference 3D printer; locating the inspection paper irradiated with the reference pattern in a 3D printer for inspection to determine whether correction is necessary; irradiating an inspection pattern on the inspection paper with the inspection 3D printer; and determining whether the optical system correction of the 3D printer for inspection is necessary by comparing the inspection pattern with the reference pattern irradiated on the inspection paper.

In addition, in the method for determining whether correction of the optical system of the 3D printer of the present invention is necessary, the step of irradiating the inspection pattern is a step of irradiating at least a portion of the inspection pattern to be inconsistent with the reference pattern.

In addition, in the method for determining whether correction of the optical system of the 3D printer of the present invention is necessary, the preparing of the inspection paper is a step of preparing an inspection paper on which ink that is removed when irradiated is printed, and the determining step includes the reference pattern and the It is a step of determining whether correction is necessary based on the amount of the ink between the inspection patterns.

In addition, in the method of determining whether correction of the optical system of the 3D printer of the present invention is necessary, the reference pattern irradiation step comprises an X-axis pattern and a Y-axis pattern in which the reference pattern intersects each other, the X-axis pattern and the Y-axis pattern Each is a step in which a plurality of lines are spaced apart to form a pattern, and the inspection pattern irradiation step is a step of irradiating between the plurality of lines spaced apart from each other of the X-axis pattern and between the plurality of lines spaced apart from each other of the Y-axis pattern All.

In addition, in the method for determining whether correction of the optical system of the 3D printer of the present invention is necessary, the reference pattern irradiation step is a step in which the X-axis pattern and the Y-axis pattern are orthogonal to each other and irradiated in a grid pattern.

The method for determining whether correction of the optical system of the 3D printer of the present invention is necessary has the following effects.

According to the present invention, based on the amount of ink remaining without being removed between the irradiated reference patterns, it is possible to qualitatively and easily and quickly determine whether the optical system of the 3D printer for inspection needs to be corrected. Accordingly, the time and cost required for determining whether the optical system needs to be corrected can be reduced compared to the prior art. In addition, according to the present invention, a user can determine whether correction is necessary with the naked eye without a separate tool, so that an expert and a specialized tool may not be required.

1 is an example of a 3D printer including an optical system
2 is a reference pattern generated on the inspection paper.
3 is a view for explaining an inspection pattern to be generated on the inspection paper of FIG. 2
4 is a view showing a part of an example inspection pattern generated by a 3D printer requiring optical system correction;
5 is a flowchart of an example according to the present invention;
6 is a view for explaining the prior art

Among the components of the present invention to be described below, for the same components as in the prior art, reference will be made to the above prior art, and a separate detailed description thereof will be omitted.

The terminology used herein is for the purpose of referring to specific embodiments only, and is not intended to limit the present invention. As used herein, the singular forms also include the plural forms unless the phrases clearly indicate the opposite. The meaning of "comprising," as used herein, specifies a particular characteristic, region, integer, step, operation, element and/or component, and other specific characteristic, region, integer, step, operation, element, component, and/or group. It does not exclude the existence or addition of

When an element is referred to as being “connected” or “contacted” to another element, it may be directly connected or in contact with the other element, but it is understood that other elements may exist in between. it should be

The present invention relates to a method of determining whether or not the optical system correction of a 3D printer to which the optical system is applied.

Figure 1 is an example of a 3D printer including an optical system to which the present invention can be applied, Figure 2 (a) shows a reference pattern 100 generated on the inspection paper, Figure 2 (b) is Figure 2 ( Part a) of the present invention relates to a method for determining whether or not the optical system correction of a 3D printer to which the optical system is applied.

Figure 1 is an example of a 3D printer including an optical system to which the present invention can be applied, Figure 2 (a) shows a reference pattern 100 generated on the inspection paper, Figure 2 (b) is Figure 2 ( It is a partial enlarged view of a), Fig. 3 (a) is a view for showing a portion of the inspection pattern 300 to be generated on the inspection paper, Fig. 3 (b) is the inspection pattern 300 on the inspection paper is irradiated with ink 200 is removed, and FIG. 4 is a view showing a portion of the inspection pattern 300 of two examples in which it may be determined that optical system correction is necessary, and FIG. 5 is a flowchart of an example according to the present invention. to be.

The optical system may include the laser 20 (Laser) shown in FIG. 1 and a scanner (30, Scanner) capable of refracting the laser (light) formed in the laser 20, in addition to the laser 20 and the scanner It may include a lens (not shown), a mirror (not shown), etc. that may be disposed between the 30 .

Hereinafter, a preferred embodiment of the present invention will be described with reference to FIGS. 1 to 5 .

The method of determining whether the optical system of the 3D printer of this example needs to be corrected includes the steps of preparing an inspection paper (S10); Positioning the test paper on the output surface of the reference 3D printer (S20); irradiating the reference pattern 100 on the inspection paper with the reference 3D printer (S30); Positioning the inspection paper irradiated with the reference pattern 100 on the output surface 60 of the inspection 3D printer to determine whether correction is necessary (S40); irradiating the inspection pattern 300 on the inspection paper with the inspection 3D printer (S50); Comparing the reference pattern 100 and the inspection pattern 300 irradiated on the inspection paper, determining whether the optical system correction of the inspection 3D printer is necessary (S60); may include.

Specifically, the step of preparing the test paper may be a step of preparing the test paper on which the ink 200 that is removed when irradiated is printed. Therefore, the ink 200 printed on the inspection paper is irradiated with the laser 20 of the 3D printer, so that the irradiation results of each of the patterns 100 and 300 can be visually checked and compared easily. That is, the state of the optical system of the 3D printer for inspection can be easily checked.

The inspection paper is a high-gloss white CCP paper on which black ink 200 is printed, and the portion irradiated with the laser 20 may have the high-gloss white color after the ink 200 is removed.

Meanwhile, the reference pattern 100 may include an X-axis pattern 110 and a Y-axis pattern 120 that cross each other. In this specification, the X-axis pattern 110 and the Y-axis pattern 120 of the reference pattern 100 are referred to as the first X-axis pattern 110 and the first Y-axis pattern 120 , respectively.

The lines of the X festival pattern 110 are parallel to the X direction of FIGS. 2 and 3 . In addition, the lines of the Y-festival 1 pattern 120 are parallel to the Y-direction of FIGS. 2 and 3 . In this way, the first X-axis pattern 110 and the first Y-axis pattern 120 may be the same pattern, but may be arranged in different directions. For example, if the X-axis 1 pattern 110 is rotated clockwise or counterclockwise by 90 degrees, the Y-axis 1 pattern 120 may be obtained. Accordingly, the first X-axis pattern 110 and the first Y-axis pattern 120 may be orthogonal to each other. For this reason, the reference pattern 100 may be formed of a grid pattern. The details will be described later.

More specifically, the first X-festival pattern 110 may be formed by a plurality of lines spaced apart from each other, that is, the first X-festival lines 113a and 113b. In addition, the first Y-festival pattern 120 may be formed by a plurality of lines spaced apart from each other, that is, the first Y-festival lines 123a and 123b.

Specifically, a plurality of the first X-axis lines 113a and 113b may form one X-axis set 111 . In addition, a plurality of X-axis sets 111 may form the X-axis first pattern 110 . At this time, the first X-festival line 113a and 113b consists of the left X-festival first line 113a and the right X-festival first line 113b, and the ink 200 remains between them (A). In addition, in the Y-axis first pattern 120 , a plurality of the Y-axis first lines 123a and 123b may form one Y-axis set 121 . Also, a plurality of Y-axis sets 121 may form the Y-axis first pattern 120 . At this time, the first Y-festival line 123a, 123b consists of an upper Y-festival first line 123a and a lower Y-festival first line 123b, and the ink 200 remains between them (B).

2(a) as an example, two X-axis first lines 113a and 113b spaced apart by A form one X-axis set 111, and seven X-axis sets 111 are spaced apart from each other by a predetermined distance D ) are spaced apart to form an X-festival 1 pattern 110 . In addition, two Y-axis 1 lines (123a, 123b) spaced apart from each other by B constitute one Y-axis set 121, and 7 Y-axis sets 121 are spaced apart by a predetermined interval (E) to form a Y-festival 1 pattern. (120) is formed.

Specifically, the spacing A between the two X-axis first lines 113a and 113b constituting one X-axis set 111 and the width of the second X-axis line 313 to be described later of the inspection pattern 300 are the same it is preferable In the same way, the spacing B between the two Y-axis first lines 123a and 123b constituting one Y-axis set 121 is the same as the width of the Y-axis second line 323 of the inspection pattern 300 to be described later. it is preferable This is because the ink 200 does not remain in (A, B) between the X-axis 1 pattern 110 and the Y-axis 1 pattern 120 of the reference pattern 100 when the inspection pattern 300 is irradiated, so that qualitative judgment is easy to make it

In addition, as shown in FIGS. 2 and 3 , between the X-axis sets 111 (D) may be farther than (A) between the first X-axis lines 113a and 113b in the X-axis set 111 . Also, between the Y-axis sets 121 (E) may be farther than (B) between the first Y-axis lines 123a and 123b in the Y-axis set 121 .

The reference pattern 100 may form a double lattice pattern.

Specifically, in Fig. 2(a), the first X-axis lines 113a and 113b on the left of the X-axis set 111 and the first Y-axis lines 123a and 123b on the upper side of the Y-axis set 121 are combined into one grid. When the pattern, the first X-axis lines 113a and 113b on the right of the X-axis set 111 and the Y-axis first lines 123a and 123b on the lower side of the Y-axis set 121 are another grid pattern, respectively, A double lattice pattern can be formed by partially overlapping the lattice patterns of .

As shown in FIG. 2, since the reference pattern 100 is irradiated with the orthogonal grid patterns spaced apart from each other in an oblique direction, on the inspection paper, the ink 200 is placed between the grid patterns (A, B). It may remain in the form of a dashed line. Accordingly, the ink 200 may remain in the inner portion where the first X-axis pattern 110 and the first Y-axis pattern 120 intersect orthogonally. In this case, the remaining ink 220 may be a reference point for correction of the optical system, that is, the XY coordinates 220 for each position described in the background art.

In addition, in this state, when the inspection pattern 300 is irradiated and the dashed-dotted line is completely removed, it can be determined that correction of the optical system is not required.

In addition, in the determining step, the ink remaining without being removed between (A, B) between the X-axis 1 pattern 110 and the Y-axis 1 pattern 120 of the irradiated inspection pattern 300 and the reference pattern 100 . It may be a step of determining whether optical system correction is necessary based on the amount (200).

For example, if the remaining ink 200 is visually observed, it may be determined that correction is necessary. That is, it is possible to easily and conveniently determine whether the optical system of the 3D printer for inspection needs to be calibrated qualitatively. Accordingly, the time and cost required for determining whether the optical system correction is necessary can be reduced.

On the other hand, the irradiation step of the inspection pattern 300 is, in the reference pattern 100, between the plurality of first X-axis lines 113a and 113b spaced apart from each other (A) and the plurality of Y-axis first lines spaced apart from each other ( It may be a step of irradiating the ink 200 between (B) 123a and 123b. That is, the step of irradiating the inspection pattern 300 may be a step of irradiating the inside of the portion surrounded by the reference pattern 100 .

Specifically, the inspection pattern 300 may be formed of a second X-axis pattern 310 and a second Y-axis pattern 320 .

At this time, the X-festival 2 pattern 310 is parallel to the X direction shown by the arrow in Fig. 3(a). In addition, the Y-festival 2 pattern 320 is parallel to the Y direction shown by the arrow in FIG. 3(a).

The second X-festival pattern 310 may include a plurality of X-festival two lines 313 spaced apart from each other by a predetermined interval. In the same way, the Y-festival 2 pattern 320 may be formed by a plurality of Y-festival 2 lines 323 spaced apart from each other by a predetermined interval.

In Figure 2 (a), the X-festival 2 lines 313 is shown in 7 lines, the Y-festival 2 lines 323 is also shown in 7 lines.

As shown in FIG. 2A , the second X-axis pattern 310 and the second Y-axis pattern 320 may cross each other to be orthogonal to each other. Accordingly, the inspection pattern 300 may form a grid pattern as shown in FIG. 3( a ).

Meanwhile, the step of irradiating the inspection pattern 300 may be a step of irradiating at least a portion of the inspection pattern 300 so that it does not match the reference pattern 100 . That is, if the inspection pattern 300 does not match the reference pattern 100 , the irradiated inspection pattern 300 and the reference pattern 100 can be checked, respectively, so that the user sees each pattern 100 and 200 and adjusts the correction of the optical system. It can be helpful in intuitively, that is, qualitatively judging whether it is necessary.

Specifically, as shown in FIG. 3A , the second X-axis pattern 310 of the inspection pattern 300 may orthogonally cross the Y-axis first pattern 120 of the reference pattern 100 . Accordingly, a portion of the second X-axis pattern 310 may be inconsistent with the first Y-axis pattern 120 . Also, the second Y-axis pattern 320 of the inspection pattern 300 may cross orthogonally cross the first X-axis pattern 110 of the reference pattern 100 . Accordingly, a portion of the Y-axis 2 pattern 320 may be inconsistent with the X-axis first pattern 110 . As such, when the inspection pattern 300 and at least a portion of the reference pattern 100 do not match, the inspection results of the reference pattern 100 and the inspection pattern 300 of the inconsistent portion can be checked, respectively, so it is helpful in determining whether correction is necessary. can be

Hereinafter, an example of a method for determining whether the optical system correction of the 3D printer is necessary will be described.

First, a test paper on which black ink 200 is printed on CCP paper of high gloss white is prepared (S10).

Thereafter, the inspection paper is positioned on the output surface of the reference 3D printer at a position where the molding plate is to be located (S20).

Thereafter, the reference pattern 100 of the double grid pattern is irradiated on the inspection paper with the laser 20 of the reference printer and generated (S30). In this case, the reference pattern 100 may include the first X-axis pattern 110 and the first Y-axis pattern 120 that cross each other orthogonally.

Thereafter, the inspection paper on which the reference pattern 100 is generated is positioned at a position where the molding plate is to be located among the output surface 60 of the 3D printer for inspection ( S40 ).

Thereafter, the inspection pattern 300 of the grid pattern is irradiated with the laser 20 of the 3D printer for inspection on the inspection paper on which the reference pattern 100 is generated (S50). In this case, the inspection pattern 300 may include the second X-axis pattern 310 and the second Y-axis pattern 320 that cross each other orthogonally. Specifically, the inspection pattern 300 may be generated by irradiating (A) between the first X-axis lines 113a and 113b of the reference pattern 100 and between the Y-axis first lines 123a and 123b (B).

Thereafter, the inspector simply determines whether the optical system correction of the inspection 3D printer is necessary (S60). Specifically, the inspector qualitatively determines the amount of ink 200 in the inner part surrounded by the one grid pattern and the other grid pattern of the reference pattern 100 on the inspection paper, and the optical system of the 3D printer for inspection Determine whether correction is necessary.

For example, FIG. 4 shows an example in which it is determined that correction of the optical system of the 3D printer for inspection is necessary. Fig. 4 (a) is a case in which there are a part of the first X festival line (113a, 113b) and the Y festival 1 line (123a, 123b), Fig. 4 (b) is the X festival 1 pattern 110 is removed and the Y festival This is a case where there is a part of one line (123a, 123b).

Conversely, as an example in which it can be determined that the 3D printer for inspection does not need correction of the optical system compared to the reference 3D printer, in FIG. All of the ink 200 between A) and the first Y-axis lines 123a and 123b (B), that is, the inner portion surrounded by the grid pattern, is not removed. That is, the portion of the inspection paper irradiated with the reference pattern 100 and the inspection pattern 300 may be white in a grid pattern as shown in FIG. 3(b).

If it is determined that the optical system correction is necessary through the above-described method, the optical system correction may be performed through the correction software described in the background art. That is, in the present invention, whenever it is necessary to determine whether optical system correction is necessary, the image is converted from the paper on which the pattern is generated as in the prior art to a scanner or vision, and the converted image and the original image are compared to check whether the error of the pattern is greater than or equal to a threshold You do not have to do. Therefore, the present invention can reduce the time and cost required for determining whether the optical system needs to be corrected, the user can visually and qualitatively determine whether or not correction is necessary without a separate tool, and experts and professional tools may not be necessary.

On the other hand, the reference 3D printer may have already completed optical system calibration or may be a new product. That is, the reference 3D printer may be a printer that does not require calibration.

Meanwhile, in the reference pattern 100 , the intervals A, B, D, and E between the lines 113a, 113b, 123a, and 123b or the sets 111 and 121 can be adjusted according to the level of precision. Also, in the inspection pattern 300 , the interval between the second lines 313 and 323 may be adjusted according to the level of precision. That is, the size of the grid pattern of the patterns 100 and 200 may be adjusted according to the level of precision.

Meanwhile, in FIG. 2A , A and B may have the same width, and D and E may have the same width.

As described above, although described with reference to preferred embodiments of the present invention, those of ordinary skill in the art may vary the present invention within the scope without departing from the spirit and scope of the present invention described in the claims below. It can be implemented by changing or modifying it.

** DESCRIPTION OF MAIN SYMBOLS **
100: reference pattern 110: X-axis pattern
111: X-axis set 113: X-festival 1 row
120: Y-axis pattern 121: Y-axis set
123: Y festival 1 line 200: ink
220: XY coordinates 300: inspection pattern
310: X festival 2 pattern 313: X festival 2 lines
320: Y festival 2 pattern 323: Y festival 2 lines
A, B: Space between lines (between) D, E: Space between sets

Claims (5)

In the method of determining whether the optical system correction of a 3D printer to which the optical system is applied,
preparing a test paper;
positioning the test paper in a reference 3D printer;
irradiating a reference pattern on the inspection paper with the reference 3D printer;
locating the inspection paper irradiated with the reference pattern in a 3D printer for inspection to determine whether correction is necessary;
irradiating an inspection pattern on the inspection paper with the inspection 3D printer;
Comparing the reference pattern and the inspection pattern irradiated on the inspection paper, determining whether the optical system correction of the inspection 3D printer is necessary;
The test paper preparation step is a step of preparing an inspection paper on which ink that is removed when irradiated is printed,
The determining step is a step of determining whether or not correction is necessary based on the amount of ink between the reference pattern and the inspection pattern. The method according to claim 1,
The inspection pattern irradiation step is a step of irradiating at least a portion of the inspection pattern to be inconsistent with the reference pattern. delete The method according to claim 1 or 2,
The reference pattern irradiation step is a step in which the reference pattern is made of an X-axis pattern and a Y-axis pattern that intersect each other, wherein each of the X-axis pattern and the Y-axis pattern is a step in which a plurality of lines are spaced apart to form a pattern,
The inspection pattern irradiation step is a step of irradiating between a plurality of lines spaced apart from each other of the X-axis pattern and between a plurality of lines spaced apart from each other of the Y-axis pattern. 5. The method according to claim 4,
The reference pattern irradiation step is a step in which the X-axis pattern and the Y-axis pattern are orthogonal to each other and irradiated as a grid pattern. A method for determining whether correction of the optical system of a 3D printer is necessary

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