JP2019158361A - Distance meter calibration method and calibration jig used for it - Google Patents

Abstract

To provide a distance meter calibration method capable of performing efficient calibration for thickness measurement using a two-dimensional distance meter, and a calibration jig used for it.SOLUTION: This is a distance meter calibration method for calibrating the arrangement of the two-dimensional distance meter 10 to determine a distance to an object, in which a measurement object transported in the Y direction on the pass line G is vertically irradiated with a line light P1 which is long in the X direction perpendicular to the Y direction, and the line-shaped reflected light reflected by the measurement object is detected and the distance to the object is obtained. A calibration jig 20 having a first height region 30 and a second height region 28 having a different height from the first height region 30 in which a first and second marks 31, 33 having different arrangements in different Y directions are provided at intervals is irradiated with a line light P1, and a reflected light L1' which passes the first and second marks 31, 33 is reflected, and by detecting the reflected light L1', an inclination of the irradiation direction of the line light P1, positional deviations of the two-dimensional distance meter 10 in the X and Y directions, and an inclination of the longitudinal direction of the line light P1 with respect to the X direction is detected.SELECTED DRAWING: Figure 5

Description

The present invention relates to a distance meter calibration method for calibrating the arrangement of a two-dimensional distance meter for obtaining a distance to a measurement object being conveyed, and a calibration jig used therefor.

In equipment that measures the thickness of the measurement object by placing laser distance meters above and below the measurement object, the position and inclination of the laser distance meter greatly affects the measurement accuracy. It is important to measure and calibrate and tilt. Specific examples of the measurement of the position and tilt of the laser distance meter are described in Patent Documents 1 to 3, for example.
In Patent Document 1, after measuring a distance from a laser distance meter to a first calibration plate arranged at a predetermined position, the first calibration plate is changed to a second calibration plate having a thickness different from that of the first calibration plate, and a laser is measured. A method is described in which the distance from the distance meter to the second calibration plate is measured and the deviation (deviation) of the inclination of the laser distance meter is obtained from the two measured values.

Patent Document 2 describes a method of measuring the thickness of a calibration plate having two parts having different thicknesses and correcting the measurement value of the thickness of the object to be measured (measurement object) based on the measurement result. ing.
In Patent Document 3, two thickness measuring devices are arranged in the moving direction of an object to be measured (measurement target), a calibration value is obtained using a reference plate with one thickness measuring device, and measured with the other thickness measuring device. The method of correcting the thickness of the measured object based on the calibration value and removing the thickness measurement error due to temperature drift is described.

JP 2009-31120 A JP 2012-229955 A JP 2013-137197 A

By the way, in recent years, when measuring the thickness of a measurement object, a technology that employs a two-dimensional laser distance meter (hereinafter also referred to as a “two-dimensional distance meter”) as a laser distance meter disposed facing the measurement object in the vertical direction. Has been developed. In the thickness measurement technique using such a two-dimensional distance meter, the technique described in Patent Documents 1 to 3 cannot be applied, or the calibration work becomes inefficient due to the application of the technique. There was a problem.
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a distance meter calibration method capable of efficiently calibrating thickness measurement using a two-dimensional distance meter and a calibration jig used therefor.

In the distance meter calibration method according to the first aspect of the present invention, the line light that is long in the X direction perpendicular to the Y direction is vertically projected from above the measurement object that is conveyed in the Y direction that is the conveyance direction. A distance meter calibration method for calibrating the arrangement of a two-dimensional distance meter for detecting a line-shaped reflected light α reflected on the measurement object and obtaining a distance to the measurement object, A calibration jig having a first height region in which first and second marks are provided at an interval, and a second height region having a height different from the first height region is provided as the two-dimensional distance meter. When the line light is irradiated and reflected by the calibration jig, the line-shaped jig reflected light is reflected by the first reference point of the first mark and the second mark. A predetermined relationship in the X direction with respect to the position passing through the second reference point and the target position. Irradiating the line light from the two-dimensional distance meter which is a calibration target of the arrangement, and reflecting light β passing through the first and second marks and the second height region. And detecting a distance from the two-dimensional distance meter to the first height region and a distance from the two-dimensional distance meter to the second height region based on the detected reflected light β. Then, the inclination of the irradiation direction of the line light is obtained, the positional relationship in the Y direction of the portion of the reflected light β passing through the first mark with respect to the first reference point, and the reflected light β with respect to the second reference point. And detecting the positional displacement in the Y direction of the two-dimensional distance meter, and the inclination of the line light in the longitudinal direction with respect to the X direction, Detecting the positional relationship in the X direction of the reflected light β with respect to the calibration jig, A step of detecting a positional deviation in the X direction of the two-dimensional distance meter, wherein the first mark has a different arrangement of different parts in the Y direction, and the second mark has a different part in the Y direction. Each arrangement is different.

The calibration jig according to the second aspect of the invention that meets the above object is a line light that is long in the X direction perpendicular (orthogonal) to the Y direction from above the measurement object that is conveyed in the Y direction, which is the conveyance direction, of the pass line. Is used to calibrate the arrangement of a two-dimensional rangefinder that detects the line-shaped reflected light reflected by the measurement object and obtains the distance to the measurement object. A calibration jig that includes a first height region irradiated with the line light, and a second height region irradiated with the line light, the height of which is different from the first height region. In the first height region, a first mark having a first reference point and a second mark having a second reference point are provided at an interval, and the first reference point and the second reference point are provided. The points are arranged along the X direction, and the first mark is a different part in the Y direction. Arrangement differs respectively, the second mark is located in different parts of the Y direction are different, respectively.

The distance meter calibration method according to the first invention includes a first height region in which the first and second marks are provided at an interval, and a second height region having a height different from that of the first height region. Various positions of the two-dimensional distance meter using calibration jigs having different arrangements of the different parts of the first mark in the Y direction and different arrangements of the different parts of the second mark in the Y direction. Since displacement is detected, it is possible to perform efficient calibration for thickness measurement using a two-dimensional distance meter. In addition, since the calibration jig according to the second invention also has the same configuration, it is possible to perform efficient calibration for thickness measurement using a two-dimensional distance meter.

It is explanatory drawing of the installation with which the distance meter calibration method which concerns on one embodiment of this invention is applied. It is explanatory drawing of the installation. (A), (B) is explanatory drawing which shows the mode of reflection of the reflected light in the said installation, respectively. (A), (B), (C) is explanatory drawing which shows the state by which the two-dimensional distance meter is not arrange | positioned in the target position, respectively. (A), (B) is explanatory drawing of the calibration jig used for the distance meter calibration method which concerns on one embodiment of this invention, respectively, (C) shows a mode that this calibration jig is used. It is explanatory drawing. (A), (B) is explanatory drawing which shows the inclination of the Y direction of a two-dimensional distance meter, respectively. (A) is explanatory drawing of the two-dimensional rangefinder which is not inclined to X direction, (B), (C) is explanatory drawing which shows the line light irradiation direction position of reflected light, respectively. (A) is explanatory drawing of the two-dimensional rangefinder inclined in the X direction, (B) is explanatory drawing which shows the line light irradiation direction position of reflected light. (A), (B), (C) is explanatory drawing of the reflected light respectively imaged by the imaging part. (A), (B) is explanatory drawing of the calibration jig which concerns on a modification, respectively.

Next, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.
As shown in FIGS. 1, 2, 3 (A), and 3 (B), the distance meter calibration method according to an embodiment of the present invention is a steel material that is conveyed in the Y direction, which is the conveyance direction, along the pass line G. (Example of Measurement Object) From the upper side of S, line-like reflected light L1 (irradiation of reflected light α) that is irradiated vertically with vertical line light P1 in the X direction perpendicular to the Y direction and reflected by the steel material S This is a method of calibrating the arrangement of the two-dimensional distance meter 10 that detects the example) and determines the distance to the steel material S. Details will be described below.
Note that the upward direction that is perpendicular to the Y direction and the X direction is the Z direction.

In this Embodiment, as shown in FIG. 1, FIG. 2, the steel material S is mounted and conveyed on the roller conveyor which is arrange | positioned horizontally and which is not shown in figure. In the present embodiment, the pass line G is arranged horizontally, and the Y direction is a direction along the pass line G.

Above the pass line G, a plurality of two-dimensional rangefinders 10 are arranged in the X direction at intervals, and below the pass line G, a plurality of two-dimensional rangefinders 11 are arranged in the X direction at intervals. It has been.
Each two-dimensional distance meter 10 has a laser irradiation unit 12 that irradiates a line light P1 that is long in the X direction in the Z direction and an imaging unit 13 that images the reflected light L1 on the upper surface S1 of the steel material S being conveyed. ing.

In order to avoid the interference of the adjacent reflected light L1, as shown in FIGS. 3A and 3B, the irradiation of the line lights P1 and P2 by the two-dimensional distance meters 10 and 11 positioned at odd numbers in the X direction; Irradiation of the line lights P1 and P2 by the two-dimensional distance meters 10 and 11 positioned evenly in the X direction is performed at different timings.
The line-shaped reflected light L1 that is long in the X direction is reflected on the upper surface S1 of the steel material S by the irradiation of the line light P1 from the laser irradiation unit 12.

As shown in FIGS. 1 and 2, each two-dimensional distance meter 11 includes a laser irradiation unit 14 that irradiates a lower surface S <b> 2 of the steel material S being conveyed with a line light P <b> 2 that is long in the X direction in the Z direction, and reflected light. The imaging unit 15 that images L2 (an example of the reflected light α) is provided. 3A and 3B, the line-shaped reflected light L2 that is long in the X direction is reflected by the lower surface S2 of the steel material S by the irradiation of the line light P2 from the laser irradiation unit 14.
The laser irradiation unit 12 of each two-dimensional distance meter 10 is disposed to face the laser irradiation unit 14 of each two-dimensional distance meter 11.

Each reflected light L1 is reflected at the same position in the Y direction of the steel material S, and each reflected light L2 is reflected at the same position in the Y direction of the steel material S. The two-dimensional distance meters 10 and 11 each have an information processing unit (not shown). The information processing unit of the two-dimensional distance meter 10 detects the reflected light L1 from the captured image of the imaging unit 13 and uses the principle of triangulation. The distance from the two-dimensional distance meter 10 to the upper surface S1 of the steel material S is measured, and the information processing unit of the two-dimensional distance meter 11 is also processed from the two-dimensional distance meter 11 by the same processing as the information processing unit of the two-dimensional distance meter 10. The distance to the lower surface S2 of the steel material S is measured.

As shown in FIG. 1, each two-dimensional distance meter 10, 11 is connected to a thickness deriving machine 17 through an amplifier 16, and the thickness deriving machine 17 is connected to the upper surface S <b> 1 of the steel material S from each two-dimensional distance meter 10. Distance from each two-dimensional distance meter 11 to the lower surface S2 of the steel material S, distance from each two-dimensional distance meter 10 to the pass line G, and distance from each two-dimensional distance meter 11 to the pass line G Based on this, the thickness from one end of the steel material S to the other end is derived.

Here, in order to accurately derive the thickness of the steel material S, it is important that the two-dimensional distance meters 10 and 11 are arranged at target positions with respect to the pass line G. In the present embodiment, the two-dimensional rangefinders 10 and 11 are arranged at the target position. The two-dimensional rangefinders 10 are arranged at the same height and at the same pitch in the X direction. Are arranged at the same height and at equal pitches in the X direction, and each two-dimensional distance meter 10 irradiates the line light P1 downward along the Z direction, that is, in a direction perpendicular to the pass line G. This means that the distance meter 11 is arranged so as to irradiate the line light P2 upward along the Z direction, that is, in a direction perpendicular to the pass line G.

FIGS. 4A, 4B, and 4C show thickness measurement errors with respect to the measurement object W that may occur due to the two-dimensional distance meters 10 and 11 not being arranged at the target positions, respectively. As shown, 1) two-dimensional rangefinders 10, 11 are tilted in the Y direction, two-dimensional rangefinders 10, 11 are displaced in the Y direction, and 2) two-dimensional distances. 3) The two-dimensional distance meters 10 and 11 are rotated in the XY plane (pass line G). There is something that is out of place.

Therefore, as shown in FIGS. 5A, 5 </ b> B, and 5 </ b> C, the two-dimensional distance meters 10, 11 irradiate the calibration jig 20 with the line lights P <b> 1, P <b> 2, respectively. 11, Y-direction tilt, Y-direction displacement, X-direction tilt, X-direction displacement and rotation-direction displacement in the XY plane are detected, and each two-dimensional distance meter 10 is detected based on the detection result. , 11 is calibrated.

The calibration jig 20 includes rectangular parallelepiped blocks 21 and 22 that are provided at intervals and a block 23 that is provided between the blocks 21 and 22.
As shown in FIGS. 5B and 5C, the calibration jig 20 has an opposing surface 24 (first portion) and surface 25 of the block 21 arranged vertically, and an opposing surface 26 of the block 22. (Second part) and the surface 27 are arranged up and down, the opposing surface 28 (second height region) and the surface 29 of the block 23 are arranged up and down, respectively, and the blocks 21, 23 and 22 are arranged in the X direction. Used in order. In this state, the surfaces 24 to 29 are disposed horizontally, the surfaces 24 and 26 are disposed at the same height, the surfaces 25 and 27 are disposed at the same height, and the surface 28 is disposed at a position lower than the surfaces 24 and 26. The surface 29 is arranged at a position higher than the surfaces 25 and 27.

In the present embodiment, as shown in FIGS. 5A and 5B, the first height region 30 is configured by combining the surface 24 of the block 21 and the surface 26 of the block 22. The area 30 is provided with surfaces 24 and 26 spaced apart. The surface 28 (that is, the second height region) is disposed between the surfaces 24 and 25 in plan view and is different in height from the first height region 30.
The block 21 is provided with marks 31 (first marks) and marks 32 on the surfaces 24 and 25, respectively, and the block 22 is provided with marks 33 (second marks) and marks 34 on the surfaces 26 and 27, respectively. It has been. Therefore, the marks 31 and 33 are provided at intervals, and the marks 32 and 34 are provided at intervals.

The marks 31 to 34 are figures drawn in the same position in the Y direction of the surfaces 24 to 27 in colors different from the colors around the marks 31 to 34 of the calibration jig 20, and have the same size and shape. Specifically, the figure is obtained by adding a vertical line to the letter X, and one end of the vertical line is at the center of the letter X (the intersection of the letters X and the centers of the marks 31 to 34). It is arranged and extends a predetermined length in the Y direction. Accordingly, the arrangement of the portions of the mark 31 (the same applies to the marks 32, 33, and 34) in the Y direction is different.

Therefore, each of the marks 31 to 34 can specify the position of the portion in the Y direction based on the arrangement of the portion disposed at an arbitrary position in the Y direction.
Hereinafter, the center of the letter X of the mark 31 is the reference point 35 (first reference point), the center of the letter X of the mark 32 is the reference point 36, and the center of the letter X of the mark 33 is the reference point 37 (first point). 2), and the center of the letter X of the mark 34 is the reference point 38.

As shown in FIGS. 5A and 5C, the distance meter calibration method using the calibration jig 20 is such that the two-dimensional distance meters 10 and 11 respectively provided above and below the pass line G are correctly arranged at the target position. The line-shaped jig reflected light L1 ′ irradiated with the line light P1 from the two-dimensional distance meter 10 and reflected by the calibration jig 20 passes through the reference points 35 and 37, and the two-dimensional distance. The line-shaped jig reflected light L2 ′ irradiated with the line light P2 from the total 11 and reflected by the calibration jig 20 passes through the reference points 36 and 38, and at the target position of the two-dimensional distance meters 10 and 11. On the other hand, the calibration jig 20 is arranged at a position having a predetermined relationship in the X direction. At this time, the calibration jig 20 is arranged such that the surfaces 24 to 29 are horizontal, the reference points 35 and 37 are along the X direction, and the reference points 36 and 38 are along the X direction.

Next, as shown in FIG. 5C, from the actual two-dimensional rangefinders 10 and 11 (two-dimensional rangefinders 10 and 11 to be calibrated) arranged respectively above and below the calibration jig 20. The line lights P1 and P2 are respectively irradiated, and the reflected light L1 ′ (an example of the reflected light β) passing through the marks 31 and 33 and the surface 28 is reflected by the surfaces 24, 28, and 26 of the calibration jig 20, and the marks 32, 34 and the reflected light L2 ′ passing through the surface 29 (an example of the reflected light β) are reflected by the surfaces 25, 29, and 27 of the calibration jig 20, and the image processing unit 13 The reflected lights L1 ′ and L2 ′ are detected based on the 15 captured images.

Then, based on the detected reflected light L1 ′, the information processing unit of the two-dimensional distance meter 10 uses the principle of triangulation to face the surfaces 24 and 26 (that is, the first height region 30) from the two-dimensional distance meter 10. , And the distance from the two-dimensional distance meter 10 to the surface 28 (ie, the second height region), the inclination of the irradiation direction of the line light P1 with respect to the X direction and the Y direction is obtained and detected. Based on the reflected light L2 ′, the information processing unit of the two-dimensional distance meter 11 uses the triangulation principle to measure the distance from the two-dimensional distance meter 11 to the surfaces 25 and 27, and the two-dimensional distance meter 11 to the surface 29. The distance to the X direction and the Y direction of the irradiation direction of the line light P2 is obtained. Hereinafter, the point that the inclination of the irradiation direction of the line light P1 with respect to the X direction and the Y direction can be detected based on the distance from the two-dimensional distance meter 10 to the surfaces 24, 26, and 28 will be described.

When the two-dimensional distance meter 10 is disposed at the target position and is not inclined in the Y direction, the reflected light L1 ′ detected by the information processing unit of the two-dimensional distance meter 10 is used as shown in FIG. The difference between the height position of the surfaces 24 and 26 and the height position of the surface 28 calculated in the above is the actual difference between the height position of the surfaces 24 and 26 and the height position of the surface 28 (hereinafter referred to as “actual height”). It is also called “positional difference”).

On the other hand, when the two-dimensional distance meter 10 is disposed to be inclined in the Y direction, the irradiation direction of the line light P1 of the laser irradiation unit 12 is non-perpendicular to the Y direction as shown in FIG. . When the difference in actual height position is d and the angle at which the two-dimensional distance meter 10 is tilted in the Y direction is θ, the difference is calculated based on the reflected light L1 ′ detected by the information processing unit of the two-dimensional distance meter 10. The difference between the height position of the surfaces 24 and 26 and the height position of the surface 28 is d / cos θ, and is calculated based on the reflected light L1 ′ detected by the information processing unit of the two-dimensional distance meter 10. The difference between the height position 26 and the height position of the surface 28 is larger than the difference between the actual height positions.

In the present embodiment, the actual height position difference, that is, the value of d is registered in advance in the thickness deriving device 17, and the thickness deriving device 17 is measured by the information processing unit of the two-dimensional distance meter 10. Based on the distance from the dimensional distance meter 10 to the surfaces 24 and 26 and the distance from the two-dimensional distance meter 10 to the surface 28, the difference between the height position of the surfaces 24 and 26 and the height position of the surface 28 is calculated. Compare the difference between the calculated value and the actual height position. Accordingly, the inclination of the irradiation direction of the line light P1 with respect to the Y direction can be detected based on the distances from the two-dimensional distance meter 10 to the surfaces 24, 26, and 28.

In addition, when the two-dimensional distance meter 10 is arranged at the target position as shown in FIG. 7A and is not inclined in the X direction, the irradiation direction of the line light P1 with respect to the two-dimensional distance meter 10 is used. As shown in FIG. 7B, the coordinate positions of are equal at different portions of the surface 24 in the X direction.
On the other hand, when the two-dimensional distance meter 10 is tilted in the X direction as shown in FIG. 8A, the coordinate position in the irradiation direction of the line light P1 with respect to the two-dimensional distance meter 10 is As shown in FIG. 8B, the surface 24 differs at different locations in the X direction. The same applies to the distance from the two-dimensional distance meter 10 to the surfaces 26 and 28.

Therefore, by comparing the coordinate positions in the irradiation direction of the line light P1 with respect to the two-dimensional distance meter 10 at different locations in the X direction on the surface 24 (or the surface 26 or the surface 28), the two-dimensional distance meter 10 The inclination of the irradiation direction of the line light P1 with respect to the X direction can be detected.
The principle of detecting the inclination of the irradiation direction of the line light P2 of the two-dimensional distance meter 11 with respect to each of the X direction and the Y direction is to detect the inclination of the irradiation direction of the line light P1 of the two-dimensional distance meter 10 with respect to each of the X direction and Y direction. The principle is the same as that.

Further, the thickness deriving machine 17 has a positional relationship in the Y direction where the reflected light L1 ′ passes the mark 31 relative to the reference point 35 and a positional relationship in the Y direction where the reflected light L1 ′ passes the mark 33 relative to the reference point 37. And detecting the positional deviation in the Y direction of the two-dimensional distance meter 10 and the inclination of the longitudinal direction of the line light P1 (the same as the longitudinal direction of the reflected light L1) with respect to the X direction. The positional deviation in the Y direction of the two-dimensional distance meter 11 and the inclination of the longitudinal direction of the line light P2 (same as the longitudinal direction of the reflected light L2) with respect to the X direction are detected.

When the position of the two-dimensional distance meter 10 is not shifted in the Y direction, the reflected light L1 ′ passes through the reference points 35 and 37. Therefore, as shown in FIG. Each will cross at one place. On the other hand, when the position of the two-dimensional distance meter 10 is shifted in the Y direction, the reflected light L1 ′ passes through a portion other than the reference point 35 of the mark 31 and a portion other than the reference point 37 of the mark 33. As shown in (B), the reflected light L1 ′ crosses the marks 31 and 33 at a plurality of locations.

The thickness deriving machine 17 detects the positional deviation in the Y direction of the two-dimensional rangefinder 10 based on whether or not the reflected light L1 'crosses the marks 31 and 33 at one place. The positional deviation in the Y direction of the two-dimensional distance meter 11 is detected by whether or not the reflected light L2 'crosses the marks 32 and 34 at one place.

When the two-dimensional distance meter 10 is arranged at the target position and the longitudinal direction of the line light P1 is along the X direction, the Y direction position passing through the mark 31 of the reflected light L1 ′ and the mark of the reflected light L1 ′ As shown in FIGS. 9A and 9B, the number of the reflected light L1 ′ across the mark 31 and the number of the reflected light L1 ′ across the mark 33 are equal, as shown in FIGS. If the reflected light L1 ′ crosses the marks 31 and 33 at two locations (or three locations), the distance between the locations crossing the mark 31 and the distance between the locations crossing the mark 33 are equal.

On the other hand, as shown in FIG. 4C, when the two-dimensional distance meter 10 is displaced in the rotational direction in the XY plane and the longitudinal direction of the line light P1 is not along the X direction, the reflected light L1 ′. The Y-direction position passing through the mark 31 and the Y-direction position passing through the mark 33 of the reflected light L1 ′ are different. Therefore, the number of the reflected light L1 ′ crossing the mark 31 and the number of the reflected light L1 ′ across the mark 33 are different as shown in FIG. 9C, or the reflected light L1 ′ When the number of crossings is the same, the distance between the locations crossing the mark 31 and the distance between the locations crossing the mark 33 are different.

Therefore, whether or not the longitudinal direction of the line light P1 is along the X direction depends on the positional relationship of the reflected light L1 ′ passing the mark 31 with respect to the reference point 35 in the Y direction and the reflected light L1 ′ with respect to the reference point 37. It can be detected from the positional relationship in the Y direction at the location passing through the mark 33.
By the same procedure, it is possible to detect whether or not the longitudinal direction of the line light P2 is along the X direction.

Furthermore, the thickness deriving machine 17 detects the positional relationship in the X direction of the reflected light L1 ′ with respect to the calibration jig 20, detects the positional deviation in the X direction of the two-dimensional distance meter 10, and reflects the reflected light on the calibration jig 20. The positional relationship in the X direction of L2 ′ is detected, and the positional deviation in the X direction of the two-dimensional distance meter 11 is detected.
If the position of the two-dimensional distance meter 10 is not shifted in the X direction, the positional relationship in the X direction of the reflected light L1 ′ with respect to the calibration jig 20 is a predetermined position. In the present embodiment, the reflected light L1 ′ with respect to the calibration jig 20 in the X direction using the step (difference in height position) between the first height region 30 and the surface 28 (that is, the second height region). The positional relationship is measured.
Specifically, as shown in FIG. 7B, the length of the portion reflected by the surface 24 of the reflected light L1 ′ when the two-dimensional distance meter 10 is arranged at a predetermined position in the X direction. As shown in FIG. 7C, the thickness deriving device 17 detects the length Q ′ of the portion of the reflected light L1 ′ that is reflected by the surface 24, as shown in FIG.

The thickness deriving machine 17 determines that the position of the two-dimensional distance meter 10 is not shifted in the X direction if Q and Q ′ are equal, and if the Q and Q ′ are different, the position of the two-dimensional distance meter 10 is determined to be in the X direction. It is determined that it is shifted to.
The comparison target need not have the length of the portion reflected by the surface 24 of the reflected light L1 ′. For example, the comparison target has the length of the portion reflected by the surface 26 of the reflected light L1 ′. Also good.
The positional deviation in the X direction of the two-dimensional distance meter 11 can be detected by the same procedure as that of the two-dimensional distance meter 10.

Then, the two-dimensional distance meters 10 and 11 respectively disposed above and below the calibration jig 20 are inclined with respect to the X direction and the Y direction of the irradiation directions of the line lights P1 and P2, respectively. The X direction of the two-dimensional distance meters 10 and 11 The arrangement of the corresponding two-dimensional distance meters 10 and 11 is adjusted based on the result of detecting the positional deviation in the Y direction and the inclination of the line lights P1 and P2 with respect to the X direction in the longitudinal direction. Thereafter, the calibration jig 20 is moved in the X direction, and the arrangement of the other two-dimensional distances 10 and 11 is measured and adjusted in the same procedure.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and all changes in conditions and the like that do not depart from the gist are within the scope of the present invention.
For example, the first and second marks may be grooves formed in the first height region.
Further, instead of employing a calibration jig in which the first height region includes the first and second parts, for example, as shown in FIGS. A calibration jig 45 in which a second height region 44 is provided adjacent to the first height region 43 in which the two marks 41 and 42 are spaced apart from each other in the X direction may be employed.

The first mark and the second mark may be different in arrangement of portions where the first mark is different in the Y direction and different in arrangement of portions where the second mark is different in the Y direction. A shape such as the first and second marks 41 and 42 shown in FIG. In the example shown in FIG. 10A, the center of the first mark 41 (position Q1) and the second reference point are the center of the second mark 42 (position Q2), respectively. It can be set as a reference point.
Furthermore, the first and second marks may be different in size and shape.
When the steel material is not irradiated with line light from below, a calibration jig in which marks are provided only in the first height region can be employed.

10, 11: Two-dimensional distance meter, 12: Laser irradiation unit, 13: Imaging unit, 14: Laser irradiation unit, 15: Imaging unit, 16: Amplifier, 17: Thickness deriving machine, 20: Calibration jig, 21, 22 , 23: block, 24-29: plane, 30: first height region, 31-34: mark, 35-38: reference point, 41: first mark, 42: second mark, 43: first Height region, 44: second height region, 45: calibration jig, L1, L2: reflected light, L1 ′, L2 ′: reflected light, G: pass line, P1, P2: line light, S: steel material, W: Object to be measured

Claims (8)

A line-shaped reflected light α that is vertically irradiated with long line light in the X direction orthogonal to the Y direction from above the measurement object conveyed in the Y direction, which is the conveyance direction, on the pass line, and reflected by the measurement object. A distance meter calibration method for calibrating the arrangement of a two-dimensional distance meter to detect the distance to the measurement object,
A calibration jig having a first height region in which first and second marks are provided at an interval and a second height region having a height different from the first height region is defined as the two-dimensional distance. When the meter is correctly arranged at the target position, the line-shaped jig reflected light that is irradiated with the line light and reflected by the calibration jig becomes the first reference point and the second mark of the first mark. Placing the mark at a position passing through the second reference point and a predetermined relationship in the X direction with respect to the target position;
Irradiating the line light from the two-dimensional distance meter which is a calibration target of the arrangement, and detecting the reflected light β passing through the first and second marks and the second height region;
Based on the detected reflected light β, a distance from the two-dimensional distance meter to the first height region and a distance from the two-dimensional distance meter to the second height region are measured, and the line light , The positional relationship in the Y direction of the portion of the reflected light β passing through the first mark with respect to the first reference point, and the second of the reflected light β with respect to the second reference point. The positional relationship in the Y direction of the portion passing through the mark is detected, the positional deviation in the Y direction of the two-dimensional distance meter, and the inclination of the line light in the longitudinal direction with respect to the X direction are detected, and the calibration jig is Detecting a positional relationship in the X direction of the reflected light β, and detecting a positional deviation in the X direction of the two-dimensional distance meter,
A distance meter calibration method, wherein the first mark has a different arrangement of portions in the Y direction, and the second mark has a different arrangement of portions in the Y direction. In the first height region, a first portion where the first mark is provided and a second portion where the second mark is provided are provided at an interval, and the second height region is provided. The distance meter calibration method according to claim 1, wherein the distance meter is disposed between the first and second parts in a plan view. 3. The distance meter calibration method according to claim 1, wherein each of the first and second marks is provided in the first height region in a color different from a surrounding color. . 3. The distance meter calibration method according to claim 1, wherein each of the first and second marks is a groove formed in the first height region. Long line light in the X direction perpendicular to the Y direction is irradiated perpendicularly to the Y direction and the X direction from above the measurement object conveyed in the Y direction, which is the conveyance direction, and reflected by the measurement object. A calibration jig used to calibrate the arrangement of a two-dimensional distance meter that detects the reflected light in the form of a line and determines the distance to the measurement object,
A first height region irradiated with the line light and a second height region different in height from the first height region and irradiated with the line light;
In the first height region, a first mark having a first reference point and a second mark having a second reference point are provided at an interval,
The first reference point and the second reference point are arranged in a state along the X direction, the first mark is different in the arrangement of different parts in the Y direction, and the second mark is in the Y direction. A calibration jig characterized in that different parts are arranged differently. In the first height region, a first portion where the first mark is provided and a second portion where the second mark is provided are provided at an interval, and the second height region is provided. The calibration jig according to claim 5, wherein the calibration jig is disposed between the first and second portions in plan view. The calibration jig according to claim 5 or 6, wherein each of the first and second marks is provided in the first height region in a color different from a surrounding color. 7. The calibration jig according to claim 5, wherein each of the first and second marks is a groove formed in the first height region.

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