JP2018141784A - Steel plate shape measurement device and steel plate shape straightening device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a steel plate shape measurement device capable of accurately measuring a steel plate shape.SOLUTION: A steel plate shape measurement device for scanning, with a laser beam, a surface of a steel plate S placed on shape measurement areas A1, A2 set such that the steel plate S can be placed, and for ranging a predetermined detection point group on the surface of the steel plate S to measure the shape of the steel plate S from the obtained ranging data comprises: a light transmission/reception unit; and a mirror for turning the laser beam emitted from the light transmission/reception unit to reflect the laser beam to the surface of the steel plate S, and for reflecting retroreflected light from the surface of the steel plate S to the light transmission/reception unit. The shape measurement areas A1, A2 of the steel plate S are within an area in which a shade ratio indicating a reduction ratio of quantity of light of the retroreflected light from the steel plate S of the laser beam received by the mirror is less than 25%.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a steel plate shape measuring device and a steel plate shape correcting device.

  In the manufacture of steel sheets, generally, multiple rolls called cold levelers and hot levelers are arranged one above the other, and the steel sheets are transported between these rolls, thereby correcting the shape defects such as warpage and ear waves that occur during manufacturing. To do. However, in the case of a steel plate having a thickness of 40 mm or more, which is generally called a thick material, it is impossible to correct the shape defect of the tip end portion with a cold leveler or a hot leveler. Therefore, when a shape defect occurs in a thick material, the steel sheet is removed from the line, and the operator performs a shape correction by operating a pressurizing device (pressing machine) in a so-called offline.

  In order to correct the shape of the steel plate, it is necessary to accurately measure the shape of the steel plate. As an apparatus for automatically measuring the shape of a steel plate, for example, as described in Patent Document 1, a measuring device composed of a plurality of optical distance meters is installed on a steel sheet conveyance line, and the steel plate passes through this measuring device. The distance from the light reflection state to the steel sheet surface, that is, the height of the steel sheet surface is detected, and the height of the steel sheet surface is measured continuously to measure the shape of the steel sheet surface. However, the steel plate shape measuring apparatus described in Patent Document 1 is not suitable for off-line shape measurement.

  On the other hand, Patent Literature 2 proposes a shape correction device that measures the shape of a steel sheet offline. The shape measuring apparatus described in Patent Document 2 turns laser light from one laser light source with a mirror, scans the turned laser light, and measures a predetermined group of detection points on a stationary steel plate. The shape of the steel plate is measured from the detected point cloud data. Therefore, the shape of the steel plate can be measured even when the steel plate is stationary offline.

JP-A-5-237546 JP 2010-155272 A

  However, in the steel plate shape correcting device described in Patent Document 2, the installation position, orientation, and the like of the steel plate shape measuring device are not specifically described. Therefore, there is still room for improvement in measuring the shape of the steel sheet with the steel sheet shape straightening device described in Patent Document 2.

  This invention is made paying attention to the above problems, and it aims at providing the steel plate shape measuring apparatus which can measure a steel plate shape accurately. It is another object of the present invention to provide a steel plate shape correction device capable of accurately measuring the shape of a steel plate on a conveyance device before and after shape correction and the shape of a steel plate under a pressure ram during shape correction and correcting the shape with high accuracy. To do.

The gist of the present invention is as follows.
[1] A shape measurement region on which a steel plate can be placed is set, and a surface of the steel plate placed on the shape measurement region is scanned with a laser beam to measure a predetermined detection point group on the steel plate surface. A steel plate shape measuring device for measuring the shape of the steel plate from the obtained distance measurement data,
A light transmission / reception unit, a laser beam emitted from the light transmission / reception unit is reflected and reflected to the steel sheet surface, and a mirror that reflects retroreflected light from the steel sheet surface to the light transmission / reception unit,
The steel plate shape measuring apparatus, wherein the shape measuring region is in a region where a shadow rate indicating a reduction rate of the amount of retroreflected light from the steel plate of the laser beam received by the mirror is less than 25%. .
[2] The mirror is rotatable around a first rotation axis that coincides with the optical axis of the laser beam emitted from the light transmitting / receiving unit,
By changing the reflection direction of the laser light emitted from the light transmitting / receiving unit by the rotation of the mirror, the irradiation position of the laser light can be freely adjusted along a predetermined first direction in the steel plate surface. The steel sheet shape measuring apparatus according to [1], characterized in that:
[3] A turntable that holds the light transmission / reception unit and the mirror and is rotatable around a second rotation axis orthogonal to the first rotation axis;
A rotation drive unit that rotates a turntable around the second rotation axis;
Have
According to [2], the irradiation position of the laser beam can be freely adjusted along the second direction orthogonal to the first direction in the surface of the steel sheet by the rotation of the turntable. Steel plate shape measuring device.
[4] The second rotating shaft is
Not perpendicular to the steel sheet surface,
When the angle of the orthogonal projection of the second rotation axis to the plane parallel to the steel sheet surface with respect to the longitudinal direction of the steel sheet is A degrees, the A degree is 10 degrees or more [3. ] The steel plate shape measuring apparatus of description.
[5] About orthographic projection of the second rotation axis onto a plane parallel to the steel plate surface,
When the angle formed by two straight lines at the end of the region where the shadow ratio is 25% or more is B degrees,
The steel sheet shape measuring apparatus according to [4], wherein the degree A is (B / 2) degrees or more and 90 degrees or less. However, B is greater than 0 and less than 180.
[6] The steel sheet shape measuring apparatus according to [4] or [5], wherein the A degree is 50 degrees to 70 degrees.
[7] In a steel plate shape correcting device having a press machine provided with a pressurizing ram, and a transport device that is provided on the entry side and the exit side of the press machine and transports a steel material,
The steel plate shape measuring device according to any one of [1] to [6] is provided on the entry side and / or the exit side of the press machine,
The shape measurement region is set to include at least one of the entrance side or the exit side conveying device,
A steel plate shape correction device, wherein a part of the shape measurement region of at least one of the steel plate shape measurement devices arranged on the entry side or the exit side is in the press machine.

  According to the steel plate shape measuring apparatus of the present invention, the steel plate shape can be accurately measured. Moreover, according to the steel plate shape correcting device of the present invention, the steel plate shape on the conveyance device before and after the shape correction and the steel plate shape under the pressure ram during the shape correction are efficiently measured, and the shape is accurately corrected. be able to.

It is a figure for demonstrating schematic structure of the steel plate shape correction apparatus of this embodiment. It is a figure for demonstrating schematic structure of the laser distance meter of the steel plate shape measuring apparatus of FIG. It is a schematic diagram which shows the irradiation state of the laser beam to the steel plate S by a steel plate shape measuring device, (a) shows a state where the shadow rate is less than 0%, and (b) shows a shadow rate of more than 0% to less than 50%. (C) shows a state (blind spot region) where the shadow rate is 50% or more. It is a figure for demonstrating a blind spot area | region and a partial shadow area | region. It is a figure for demonstrating the measurement range of the shape of the steel plate by the steel plate shape measuring apparatus of FIG. It is a graph which shows the relationship between the installation angle and turning angle of the steel plate shape measuring apparatus of FIG. Explains the second rotation axis (x 'axis), the axis perpendicular to the second rotation axis and parallel to the placement surface (y' axis), and the axis (z axis) perpendicular to the placement surface of the steel sheet shape correcting device It is a figure for doing. It is the figure which mapped the value of the influence coefficient dz / dphi of the error by a mirror rotation angle on the longitudinal direction x-width direction y coordinate when the 2nd rotation axis (x 'axis) is parallel to a mounting surface. (A) shows the case where A is 0 °, (b) shows that A is 30 °, (c) shows that A is 60 °, and (d) shows the case where A is 90 °. It is a figure which shows detection point distribution, (a) shows the case where A is 90 degrees, (b) shows the case where A is 60 degrees, respectively. It is the figure which mapped the value of the influence coefficient dz / dphi of the error by a mirror rotation angle on the longitudinal direction x-width direction y coordinate when the 2nd rotation axis (x 'axis) is orthogonal to a mounting surface. .

  Hereinafter, a steel plate shape measuring device and a steel plate shape correcting device according to embodiments of the present invention will be described with reference to the drawings.

  The steel plate shape measuring apparatus of this embodiment includes a press machine having a pressurizing ram for pressurizing a steel sheet, and a steel plate shape correcting apparatus that is provided on the entry side and the exit side of the press machine and that conveys the steel sheet. Is provided. The steel plate shape measuring device sets a shape measurement area where a steel plate can be placed, scans the surface of the steel plate placed on the shape measurement area with laser light, and measures a predetermined group of detection points on the steel plate surface. The distance is measured, and the shape of the steel sheet is measured from the obtained distance measurement data.

  And in the steel plate shape measuring apparatus of this embodiment, a shape measurement area | region becomes in the area | region where the shadow rate showing the decreasing rate of the light quantity of the retroreflection light from the steel plate of the laser beam which a mirror receives is less than 25%. Is set to

  FIG. 1 is a top view showing a schematic configuration of the steel sheet shape correcting device of the present embodiment. This steel plate shape correction apparatus corrects the shape of the steel plate S offline. In FIG. 1, reference numeral 1 denotes a press machine that corrects the shape of the steel sheet S. The entrance side of the press machine 1 (X-axis negative direction side) is the entrance bed 3 and the exit side of the press machine 1 ( In the drawing, an exit bed 4 is disposed on the X axis positive direction side). Each of the beds 3 and 4 has a large number of rollers for conveying the steel sheet S arranged in the conveying direction of the steel sheet S, and controls the conveying direction of the steel sheet S by controlling the rotation state of the rollers. Can do. That is, these beds 3 and 4 constitute a conveying device for the steel sheet S. In addition, a position detection device 7 that detects the position of the steel sheet S is provided on the sides of the entrance bed 3 and the exit bed 4. The position detection device 7 measures the shape of the steel sheet S in the transport direction by scanning the steel sheet S with the laser beam in the transport direction in the same manner as the shape measuring device described later, and from which position the steel sheet S is located. To detect.

  In the press machine 1 of the steel plate shape straightening apparatus according to the present embodiment, the steel plate S is pressed from above with the pressurizing ram 2 to mainly apply a bending moment to the steel plate S to correct the shape of the steel plate S. The shape of the steel sheet S is measured by a later-described steel sheet shape measuring device 5 installed on the side of the entrance bed 3 and the exit bed 4 (in the figure, the Y-axis negative direction side (or the Y-axis positive direction side)). To do. The parameters for correcting the shape of the steel sheet include, for example, a differential gap obtained from the shape of the steel sheet S (the maximum value of the gap between the straight jig and the steel sheet surface generated when a straight jig having a predetermined length is applied to the steel sheet surface), The pressure applied by the pressurizing ram 2, the position and interval of the floor plate called shim, and the position of the steel sheet S are mentioned. In the shape correction of the steel plate S by the press machine 1 in the steel plate shape correction device of the present embodiment, two shims are laid under the steel plate S, and the steel plate S between the shims is pressurized with the pressure ram 2. The bending moment due to the pressure ram 2 is generated in the steel plate S in the portion between the shims. In the steel plate shape correcting apparatus of the present embodiment, the above-described various parameters are adjusted in consideration of the deformation amount of the steel plate S due to this bending moment and the so-called springback amount that is the return amount when pressure is released.

  A steel plate shape measuring device 5 can be installed on the side of the entrance bed 3 and the exit bed 4, and a control device 6 can be installed on the side of the exit bed 4. The steel plate shape measuring device 5 turns the laser beam from one laser light source, scans the surface of the steel plate S with this laser beam, and performs distance measurement on a predetermined detection point group on the steel plate S surface, that is, a detection point group. Measure the distance to each detection point and measure the orientation of each detection point of the detection point group, associate the distance data with the orientation data, and determine the shape of the steel sheet S from the detection point group data. measure. Specifically, the steel plate shape measuring device 5 includes a laser distance meter that detects a distance to a detection point by laser light, distance data detected by the laser distance meter, and laser light irradiation when the distance data is obtained. A computer system (not shown) for measuring the shape of the steel sheet S from the orientation data is provided. The laser distance meter can measure the distance to each detection point within the scanning range by scanning the laser beam in three dimensions.

  As a method for detecting a distance with a laser distance meter, there are a known phase difference method and a Time of Flight method. The phase difference method is a method of irradiating an object with intensity-modulated laser light, receiving the reflected light with a light receiving sensor, and calculating the distance from the phase difference between the oscillated laser light and the received reflected light. The Time of Flight method is a method for calculating the distance from the time difference between the incident pulse and the reflected pulse of the laser light and the speed of the light. Regardless of whether the phase difference method or the Time of Flight method is adopted, the laser distance meter is provided with a laser light irradiation device and a laser light receiving device, thereby measuring the distance to each detection point of the steel sheet S. The shape of S can be obtained.

  FIG. 2 is a diagram for explaining a schematic configuration of the laser distance meter of the steel plate shape measuring apparatus 5. As shown in FIG. 2 (a), the laser distance meter of the steel plate shape measuring apparatus 5 includes a light transmitting / receiving unit having a laser light source that emits laser light and a light receiver that receives the laser light, and A laser beam adjusting unit that adjusts the traveling direction by reflecting the laser beam so that the irradiation position can be freely adjusted along a predetermined first direction on the surface of the steel sheet S; By rotating the laser beam adjusting unit, the traveling direction of the laser beam is adjusted so that the irradiation position of the laser beam can be freely adjusted along the second direction orthogonal to the first direction. And a rotary drive unit to be installed.

  As an example of the laser distance meter of the steel plate shape correcting apparatus of the present embodiment, as shown in FIG. 2A, the light transmitting / receiving unit 11 is mounted on the turntable 12, and is placed at the laser emission port of the light transmitting / receiving unit 11. A well-known galvanometer mirror (an example of the above-described mirror) 13 (hereinafter also simply referred to as a mirror 13) is provided. The rotation axis of the galvanometer mirror 13 corresponds to the first rotation axis in the present invention, and coincides with the optical axis of the laser beam from the laser emission port of the light transmission / reception unit 11, and the rotation axis of the galvanometer mirror 13 is the turntable 12. Is orthogonal to the rotation axis (corresponding to the second rotation axis in the present invention). In the steel plate shape measuring device 5, the shape of the steel plate S can be measured not only on the entry bed 3 and the exit bed 4 but also under the pressurization ram 2 of the press 1. Retroreflected light from the surface of the steel sheet S is reflected by the galvanometer mirror 13 and reaches the light transmitting / receiving unit 11 of the laser distance meter.

  FIG. 2B is a view of FIG. 2A as viewed from the left side of the drawing, and a part thereof is shown in a perspective view for explaining the arrangement of the apparatus components. The vertical direction in FIG. 2B matches the vertical direction in FIG. The circle at the center of FIG. 2B is the first rotation shaft provided with the galvanometer mirror 13, and the straight line extending left and right through this circle is a line indicating the horizontal direction. The galvanometer mirror 13 rotates 360 degrees around the first rotation axis (direction perpendicular to the paper surface of FIG. 2B), and the irradiation direction of the laser beam is 0 degrees around the second rotation axis. It can be turned in the range of ~ 360 degrees. The turntable 12 rotates around a second rotation axis (vertical direction in FIG. 2B), and the irradiation direction of the laser light is in a range of 0 degrees to 360 degrees around the second rotation axis. You can turn around. The rotation of the galvanometer mirror 13 and the rotation of the turntable 12 enables laser light to be irradiated in all directions.

  The rotation angles of the galvanometer mirror 13 and the turntable 12 are measured by an encoder, and the irradiation direction of the laser light can be detected from the respective rotation angle measurement results. The shape of the steel sheet S is measured by associating the distance data with the irradiation direction data obtained when the distance data is obtained for each detection point of the detection group.

  The rotation of the galvanometer mirror 13 and the rotation of the turntable 12 makes it possible to irradiate the galvanometer mirror 13 with laser light in all directions, but the turntable 12 is rotated around the second rotation axis. Since the rotation drive unit 14 is located under the turntable so as to block a part of the optical path of the laser beam, the rotation drive unit 14 becomes a hindrance and a blind spot region where the laser beam cannot be emitted from the steel plate shape measuring device 5 ( A region where the shadow rate is 50 to 100%) and a partial shadow region where all of the retroreflected light from the steel sheet S toward the galvanometer mirror 13 cannot be received by the galvanometer mirror 13 (region where the shadow rate is greater than 0% and less than 50%) ) Occurs. A region where the laser beam cannot be irradiated (dead angle region) and a region where the retroreflected light from the steel sheet S cannot be received by the galvanometer mirror 13 (partial shadow region) expands in a cone shape with the center of the galvanometer mirror 13 as the apex, The shape cannot be measured in the blind spot area. In addition, in the partial shadow region, the shape cannot be accurately measured in a region where the shadow rate is large. The region where the shadow rate is greater than or equal to a certain value also expands in a conical shape with the center of the galvanometer mirror 13 as a vertex.

  Here, the above-mentioned shadow rate is the recursion received by the mirror 13 due to the presence of an obstacle such as the rotational drive unit 14 with respect to the amount of retroreflected light received when the retroreflected light is received on the entire surface of the mirror 13. It refers to the rate of decrease in the amount of reflected light.

  As shown in FIG. 3, the laser light L emitted from the light transmission / reception unit 11 is turned by the mirror 13 and irradiated onto the steel sheet S. The retroreflected light Lout generated by the diffuse reflection on the surface of the steel sheet S is directed to the mirror 13, reflected by the mirror 13, and received by the light transmitting / receiving unit 11. When the shadow rate is 0%, it means that the retroreflected light Lout from the steel sheet S can be received by the entire surface of the mirror as shown in FIG.

  On the other hand, in the partial shadow region (region where the shadow rate is greater than 0% and less than 50%), as shown in FIG. 3B, all of the laser light L emitted from the light transmitting / receiving unit 11 and turned by the mirror 13 is obtained. The spot region is irradiated onto the surface of the steel sheet S without being obstructed by the obstacle (rotary drive unit) 14. However, retroreflected light Lout from the steel sheet S toward the mirror 13 cannot be received by the entire mirror surface due to the presence of the obstacle (rotation drive unit) 14 between the steel sheet S and the mirror. The shadow ratio is a ratio of the area of the mirror surface that does not receive the retroreflected light Lout from the steel sheet S to the area of the entire mirror surface.

  When the shadow rate increases in the partial shadow region, the amount of retroreflected light received by the light receiving element decreases, and the influence of disturbance (noise) increases, resulting in poor measurement accuracy. It becomes the same state as when the mirror is dirty. According to the study by the present inventors, it was found that in the partial shadow region where the shadow rate exceeds 25%, the influence of disturbance (noise) increases and the measurement accuracy is poor. On the contrary, it was confirmed that the measurement accuracy can be sufficiently secured if the shadow ratio is an area of less than 25%.

  In the blind spot area (area where the shadow ratio is 50 to 100%), part or all of the laser light L emitted from the light transmission / reception unit 11 and turned by the mirror 13 is blocked by the obstacle (rotation drive unit) 14. Thus, the surface of the steel sheet S is not irradiated. FIG. 3C shows a state in which a part of the laser beam L is blocked by the obstacle (rotation drive unit) 14. In this blind spot region, the laser beam is not irradiated to the steel sheet S at all, or even if it is irradiated, the light amount of the irradiated laser beam L itself decreases, and the retroreflected light Lout that the mirror 13 should receive is also reduced. Many of them are blocked by the obstacle (rotation drive unit) 14, and as a result, the amount of retroreflected light received by the light transmitting / receiving unit is insufficient. Therefore, the steel plate shape cannot be measured in this blind spot region.

  As shown in FIG. 1, the steel plate shape measuring device 5 installed on the side of the entrance bed 3 and the steel plate shape measuring device 5 installed on the side of the exit bed 4 each have a shape of the steel plate. Shape measurement areas A1 and A2 that are measurable areas are set. The shape measurement region A <b> 1 for the steel plate shape measuring device 5 installed on the side of the entry bed 3 is a region on the entry bed 3. On the other hand, the shape measurement area A2 for the steel plate shape measuring device 5 installed on the side of the exit bed 4 is an area on the exit bed 4 and an area in the press 1.

  And both shape measurement area | region A1, A2 exists in the area | region where the shadow rate of the steel plate shape measuring apparatus 5 is less than 25%. FIG. 1 shows regions B1 and B2 of the cone regions where the shadow rate is 25% or more for each of the steel plate shape measuring devices 5 and 5 as viewed from above, but the shape measurement region A1 and the shadow rate are the same. There is no overlapping area with the area B1 of 25% or more. Further, there is no overlapping area in the shape measurement area A2 and the area B2 in which the shadow rate is 25% or more. That is, with respect to the steel sheet S existing on the shape measurement region A1 or the shape measurement region A2, retroreflected light from the steel plate S can be received on the entire surface of the mirror 13 when the laser light is irradiated from the steel plate shape measuring device 5. . Therefore, accurate steel plate shape measurement can be performed by the steel plate shape measuring devices 5 and 5 for each of the shape measurement regions A1 and A2.

  As the distance between the steel plate shape measuring device 5 and the steel plate S to be measured increases, the point cloud density decreases and the distance accuracy also deteriorates. Therefore, it is desirable that the distance between the steel plate shape measuring device 5 and the measurement target (steel plate S) is small. . Therefore, it is desirable to install the steel plate shape measuring device 5 near the center in the longitudinal direction of the measurement range of the steel plate S.

  FIG. 4 is a diagram for explaining a blind spot area and a partial shadow area. In the steel plate shape correction device of the present embodiment, the position adjustment of the blind spot region and the partial shadow region has been intensively studied. For the steel plate shape measuring device 5 on the side of the entrance bed 3, the blind spot region and the shadow rate are The steel plate shape measuring device 5 is installed so that the entrance bed 3 is not located in the partial shadow region of 25% or more. Moreover, about the steel plate shape measuring apparatus 5 on the side of the exit side bed 4, the press machine 1 and the exit side bed 4 are arranged so that the blind spot region and the partial shadow region where the shadow rate is 25% or more are not located. A steel plate shape measuring device 5 is installed.

  In FIG. 4, the first direction refers to the positive / negative direction of the X ′ axis, and the laser beam irradiation position can be scanned without rotating the rotary shaft 12 that is the second rotary shaft. Point to. In FIG. 4, the second direction refers to the positive and negative direction of the Y ′ axis. The turntable 12 rotates around the X ′ axis. The X ′ axis and the Y ′ axis are axes obtained by rotating the X axis and the Y axis by the same angle around the Z axis, respectively, and are parallel to the surface of the steel sheet S of the rotation axis of the turntable 12. The orthogonal projection to the plane is parallel to the X ′ axis.

  Moreover, in the steel plate shape correction apparatus of the present embodiment, the above-described rotation axis (second rotation axis) of the turntable 12 is not perpendicular to the surface of the steel sheet S in consideration of the blind spot area and the partial shadow area, and the steel sheet S. When the angle formed by the orthogonal projection of the second rotation axis to the plane parallel to the surface with the longitudinal direction of the steel sheet S is A degrees (see symbol A in FIG. 4), the blind spot region + part of the partial shadow region A degree is set so that (the area where the shadow rate is 25% or more) does not interfere with the exit bed 4 or the press 1. For example, when the A degree is 0 degree, a part of the blind spot area + partial shadow area (area where the shadow rate is 25% or more) is closer to the exit bed 4 than the line direction line passing through the steel plate shape measuring device 5. Will also exist. When the degree A is increased, the degree of overlap of the part of the blind spot area + partial shadow area to the exit bed 4 side with respect to the line direction line passing through the steel plate shape measuring device 5 becomes smaller. In order to eliminate the presence of a part of the blind spot area + partial shadow area on the exit bed 4 side, the A degree is preferably 10 degrees or more. Thereby, the measurable range of the steel sheet S can be increased.

  Further, regarding the orthogonal projection of the second rotation axis onto the plane parallel to the steel plate surface, the angle formed by two straight lines at the end of the region where the shadow ratio is 25% or more is B degrees (in FIG. 4). The angle formed by the straight line on the blind spot region side of the rotating shaft and the longitudinal direction (line direction) of the steel sheet (that is, the above-mentioned A degree). ) Is (B / 2) degrees or more and 90 degrees or less. When A degree is (B / 2) degree or more and 90 degrees or less, the measurement precision of the shape of the steel plate S increases more.

  FIG. 5 is a diagram for explaining an example of the measurement range of the shape of the steel sheet by the steel sheet shape measuring apparatus 5. The top view of FIG. 5 shows the positional relationship between the measurement target region and the steel plate shape measuring apparatus as a top view. The left-right direction in the figure is the conveying direction of the steel plate, and is also the longitudinal direction of the steel plate. The area marked “under the press” is below the press 1, and the other part is a part of the exit bed 4. The measurement target area is 28 m below the press machine 1 (2 m before and after the center of the press machine with respect to the steel plate conveyance direction) and just below the center part of the press machine 1 of the exit bed 4 with respect to the steel plate conveyance direction. Up to a distance. The central axis (rotary axis) of the turntable 12 of the steel plate shape measuring device 5 is 14 m from the central portion of the press 1 with respect to the steel plate conveyance direction, and is 0. 0 from the end of the exit bed 4 on the steel plate shape measuring device 5 side. Located at 7m. In the figure, it is displayed as a circle with many dots drawn inside.

  Hereinafter, the full length flatness measurement mode, the press machine down measurement mode, and the half length flatness measurement mode will be described. In the second to fourth figures from the top of FIG. 5, the area surrounded by the thick line indicates the measurement target area in each measurement mode. As shown in FIG. 5, the full length flatness measurement mode is a mode capable of measuring the flatness of a maximum plate length of 28 m. The flatness measurement mode under the press machine (the flatness measurement mode under the ram) is a mode for measuring the flatness of the plate directly under the pressure ram. The semi-long flatness measurement mode is a mode in which the flatness of a maximum plate length of 16 m can be measured as an area that is slightly over half the total length of the steel plate including directly under the press. Which measurement mode is used can be appropriately set according to the properties of the steel sheet S.

  Here, the example which measures a shape for a certain steel plate S is demonstrated. When the rotation axis of the turntable 12 of the steel plate shape measuring apparatus 5 is installed parallel to the vertical axis, the rotation angle (angle α in FIG. 5) for scanning the steel plate S in the full length flatness measurement mode over the entire length is 174 degrees. The rotation angle for scanning the steel sheet S under the pressing ram 2 in the press machine flatness measurement mode (angle β in FIG. 5) is 35 degrees (hereinafter also referred to as “°”), and the semi-long flatness measurement. The rotation angle (angle γ in FIG. 5) for scanning the steel sheet S on the mode conveying device is 158 degrees.

  Although the galvano mirror 13 rotates at a high speed, the rotation speed of the turntable 12 is relatively low, so the range of change in the rotation angle of the turntable 12 determines the length of the measurement time. From the viewpoint of work efficiency, the measurement time should be as short as possible. Therefore, the range of change of the rotation angle of the turntable 12 for measurement should be as small as possible.

  When the rotation axis of the turntable 12 of the steel plate shape measuring apparatus 5 is installed perpendicularly to the vertical axis, the rotation angle around the second rotation axis necessary for measuring the total length of the predetermined range (hereinafter referred to as the turning angle). ) And the installation angle, which is a complementary angle to the angle (A degree) formed by the second rotation axis and the steel plate conveyance direction, is expressed by the full length flatness measurement mode, the press machine flatness measurement mode, and the half FIG. 6 shows each of the long flatness measurement modes. Here, the installation angle is an angle obtained by subtracting the A degree from 180 degrees in the diagram shown in FIG. The larger the turning angle, the longer the time required for rotation around the second rotation axis, and the longer the measurement takes, the worse the measurement efficiency. The blind spot is 55 degrees, and the installation angle for preventing the blind spot area from being generated on the exit bed 4 side from the position of the steel plate shape measuring device 5 is 23 to 157 degrees. In addition, the angle (= B × 2) of the region having a shadow rate of 25% or more (the blind spot region + part of the partial shadow region in FIG. 4) is 90 degrees, which is the exit bed from the position of the steel plate shape measuring device 5. The installation angle for preventing an area having a shadow ratio of 25% or more on the 4 side from being more than 45 degrees and less than 135 degrees.

  From FIG. 6, when the installation angle is 30 degrees, the turning angle in the press machine flatness measurement mode is relatively large at about 90 degrees, and the measurement efficiency in the press machine flatness measurement mode is deteriorated. When the installation angle is 90 degrees, the turning angle in the flatness measurement mode under the press machine is a minimum at about 5 degrees, while the turning angle in the full length flatness measurement mode is a maximum at about 155 degrees. When the installation angle is 150 degrees, the turning angle in the press machine flatness measurement mode is about 15 degrees, which is relatively small, and the full length flatness measurement mode turning angle is about 140 degrees. When these results are put together, the installation angle is preferably 90 to 157 degrees (23 to 90 degrees as the A degree). Although it depends on the characteristics and performance of the shape measuring device, when the turning angle is 30 degrees or less, the time required for measurement is almost the same regardless of the turning angle, and when the installation angle is 90 degrees or more. Considering that the turning angle in the half-long flatness measurement mode is monotonously decreased and the efficiency is improved, the case where the installation angle is 157 degrees is the most efficient.

  On the other hand, when the installation angle is 135 degrees or more, an area having a shadow rate of 25% or more is present on the exit bed 4 side of the steel plate shape measuring device 5 in the horizontal direction orthogonal to the line direction. Therefore, it is not preferable from the viewpoint of measurement accuracy. Therefore, from the viewpoint of achieving both measurement accuracy and measurement efficiency, specifically, the installation angle is preferably in the range of 90 to 135 degrees so as to be slightly smaller than 135 degrees. In other words, the A degree is preferably in the range of 45 to 90 degrees.

  Further, the steel plate shape measuring apparatus includes a rotation angle error dφ around the first rotation axis of the mirror 13 (hereinafter simply referred to as a mirror rotation angle error dφ) (rad), a rotation around the second rotation axis of the turntable 12. There is a three-component device error of a turning angle error dθ (hereinafter simply referred to as a turning angle error dθ) (rad) and a distance error dr (m). In order to minimize the apparatus error, which is the sum of these three component errors, the A degree is preferably 50 ° to 70 °. The reason will be described below.

  As shown in FIG. 7, the rotation axis (second rotation axis) of the turntable 12 is parallel to the conveying surface of the exit side bed 3 and the entry side bed 4, that is, parallel to the placement surface of the steel sheet S in the shape measurement region. The direction of the rotation axis (second rotation axis) of the turntable 12 is the x ′ axis, and the direction orthogonal to the x ′ axis in the plane parallel to the placement surface is y ′. If the axis and the height direction (normal direction of the plate surface of the steel sheet S) are the z-axis, the measurement error in the height direction in this case is expressed by the following equation (1).

Here, x ′ is the second rotation axis direction coordinate (distance in the x′-axis direction from the steel plate shape measuring device 5 to the measurement point) (m), y ′ is y ′ from the steel plate shape measuring device 5 to the measurement point. A distance (m) in the axial direction, Z is an installation height of the steel plate shape measuring device 5 (a distance in the z-axis direction from the steel plate shape measuring device 5 to the measurement point) (m).

  The coefficient of the distance error dr decreases as the distance from the steel plate shape measuring device 5 to the measurement point increases. This means that the influence of the distance error dr on the height direction error dz is relatively small, and the distance error dr may be ignored. The turning angle error dθ can be ignored as an apparatus error because the turning speed of the turntable 12 is relatively smaller than the rotation speed of the mirror 13 and the turn control ability of the turntable 12 is high. The mirror 13 can be rotated at a high speed. When the mirror 13 is rotated at a high speed in order to shorten the time required for measurement, the mirror rotation angle error dφ is much larger than the distance error dr and the turning angle error dθ. Therefore, if only the mirror rotation angle error dφ is regarded as the cause of the apparatus error, the influence coefficient of the error due to the mirror rotation angle can be expressed by the following equation (2) from equation (1).

  In the case where the turning axis (second rotation axis) of the turntable 12 is parallel to the mounting surface of the steel sheet S, A degree is set to 0 ° (x axis (line direction axis) and x ′) based on the equation (2). FIG. 8 shows an example in which the value of the influence coefficient dz / dφ in each region on the (x, y) coordinates on the surface of the steel sheet S when changing from 90 ° to 90 ° (which coincides with the axis) is mapped to FIG. Show. Here, the value of Z (the height from the surface of the steel sheet S at the intersection of the pivot axis of the turntable 12 and the rotation axis of the mirror 13) was 3 m. The origin on the (x, y) coordinates is the intersection of the turning axis of the turntable 12 and the rotation axis of the mirror 13. Mapping was performed for an area of 12 m before and after the line direction (24 m in total) and 6 m in the width direction (horizontal direction orthogonal to the line direction) at a certain position (the origin on the x, y coordinates) of the steel plate shape measuring apparatus. This area is an area set in consideration of the maximum length and width of the steel sheet S whose shape must be measured in actual operation.

FIG. 8A shows an example of mapping the influence coefficient dz / φ when the A degree is set to 0 ° based on the equation (2). In this case, the mirror rotation angle error dφ of the steel plate shape measuring apparatus 5 is 19 seconds (9.2 × 10 ⁻⁵ rad), and the height direction measurement error dz at the position where the influence coefficient becomes the largest is
dz = dz / dφ × dφ = 12 m / rad × 9.2 × 10 ⁻⁵ rad = 0.0011 m = 1.1 mm. The allowable range of error is 0.8 mm or less, and the height error is too large.

FIG. 8B shows an example in which the influence coefficient dz / dφ is mapped based on the equation (2) when the A degree is 30 °. In this case, the height direction measurement error at the position where the influence coefficient is the largest is
dz = dz / dφ × dφ = 12.9 m / rad × 9.2 × 10 ⁻⁵ rad = 0.0012 m = 1.2 mm. The allowable error range is 0.8 mm or less, and the height error is within the allowable range in the half length mode, but the height error is too large in the full length mode.

FIG. 8C shows an example in which the influence coefficient dz / dφ is mapped based on the equation (2) when the A degree is 60 °. The height direction measurement error at the position where the influence coefficient is the largest is dz = dz / dφ × dφ = 7.1 m / rad × 9.2 × 10 ⁻⁵ rad = 0.00065 m = 0.65 mm. The allowable range of error is 0.8 mm or less, and the height error is within the allowable range even in the full length mode.

FIG. 8D shows an example in which the influence coefficient dz / dφ is mapped based on the equation (2) when the A degree is 90 °. The height direction measurement error at the position where the influence coefficient is the largest is dz = dz / dφ × dφ = 6 m / rad × 9.2 × 10 ⁻⁵ rad = 0.00055 m = 0.55 mm. The allowable range of error is 0.8 mm or less, and the height error is within the allowable range even in the full length mode.

  As described above, when the range of the angle A that can satisfy the allowable error range is studied, if the angle is 50 ° to 130 °, the height measurement error accompanying the device error is within the allowable range.

  On the other hand, in order to improve the shape measurement accuracy of the steel sheet S, the density of detection points on the surface of the steel sheet S is also important. That is, if the number of detection points per unit length is large in both the longitudinal direction (line direction) and the width direction of the steel sheet S, the shape can be measured more precisely. The longitudinal direction of the steel sheet S is characterized in that the pitch of the change in the height position of the surface (swell pitch) is smaller than that in the width direction. In consideration of this, it is preferable that the pitch of the detection point group is smaller in the longitudinal direction of the steel sheet S, that is, it is preferable that the number of detection points per unit length in the longitudinal direction is larger.

  In FIG. 9A, when the steel plate shape measuring device 5 is installed as in FIG. 8D, that is, when the angle A degree is 90 °, the steel plate shape measuring device 5 is moved in the line direction. The detection point distribution is shown for the farthest part. Here, the range of x = 10-12 m and y = 0-2 m is shown as the farthest part in the line direction.

  As is clear from FIG. 9A, the number of detection points per unit length in the width direction (y-axis direction) is large, but the number per unit length in the longitudinal direction (x-axis direction) is small. That is, the pitch of the detection points in the longitudinal direction is larger than the pitch of the detection points in the width direction, specifically 62.5 mm. In such a case, although the pitch of the undulations on the surface of the steel sheet S is smaller in the case of being along the longitudinal direction as described above than in the case of being along the width direction, the pitch of the detection points is along the longitudinal direction. This is not preferable for the measurement of the shape of the steel sheet S because it is larger than the case along the width direction.

  Further, when the same device as the steel plate shape measuring device 5 is used as the position detecting device 7, the position in the line direction of the steel plate S is specified based on the detection point on the steel plate S on the most upstream side or the most downstream side in the longitudinal direction. However, as shown in FIG. 9A, when the pitch of the detection points in the longitudinal direction is long, the accuracy of specifying the end position of the steel sheet S is deteriorated. In the case of FIG. 9, the longitudinal position of the steel sheet S can be specified only at intervals of 62.5 mm.

  FIG. 9B shows the line direction from the steel plate shape measuring device 5 when the steel plate shape measuring device 5 is installed, that is, when the angle A is 60 °, as in FIG. 8C. Shows the detection point distribution for the farthest part. Here too, the farthest part is the range of x = 10-12 m and y = 0-2 m.

  As shown in FIG. 9B, when the angle A is 60 °, the direction in which the detection points are arranged most densely (the direction in which the number of detection points per unit length is the largest) is in the longitudinal direction (x-axis). The direction is inclined by 60 °. In this case, since the densest direction of the detection point group approaches the direction in which the waviness pitch is the narrowest, the accuracy of the shape measurement is improved as compared with the case where the A degree is 90 ° (in the case of FIG. 9A). To do.

  Moreover, even if it is a case where the apparatus similar to the steel plate shape measuring apparatus 5 is used as the position detection apparatus 7, in the case of FIG.9 (b), the specific precision of the edge part position of the steel plate S is a case of FIG.9 (a). The detection accuracy of the position in the line direction of the steel sheet S is improved.

  From the viewpoint of performing the shape measurement corresponding to the height change of a small pitch in the longitudinal direction of the steel sheet S described above, and from the viewpoint of the specific accuracy of the line direction position of the plate end of the steel sheet S, the A degree is 50 ° to 50 °. The angle is preferably 70 °.

  The above description of the preferable range of the angle A is a result of examination in the case where the x ′ axis is parallel to the mounting surface of the steel sheet S. The reason why the x′-axis is considered to be parallel to the mounting surface of the steel sheet S is that the installation of the steel sheet shape measuring device 5 in this way has the smallest error effect on the mirror rotation angle. That is, the installation method of the steel plate shape measuring device 5 in which the turning axis of the turntable 12 of the steel plate shape measuring device 5 is parallel to the mounting surface of the steel plate S in the steel plate measurement region (substantially parallel to the surface of the steel plate S) is the mirror rotation angle. Reduce the error effect of. On the contrary, when the turning axis of the turntable 12 of the steel plate shape measuring apparatus 5 is perpendicular to the surface of the steel plate S (substantially perpendicular to the surface of the steel plate S), the error effect of the mirror rotation angle becomes large and high-speed measurement is not possible. This is because it becomes possible.

  FIG. 10 shows (x, y) on the surface of the steel sheet S when the pivot axis (x ′ axis) of the turntable 12 of the steel sheet shape measuring apparatus 5 is perpendicular to the placement surface (substantially perpendicular to the steel sheet surface). The example which mapped the value of influence count dz / dphi in each area | region on a coordinate is shown. The installation position of the steel plate shape measuring device 5 is the same as in the case of FIG. 8, and the rotation axis of the turntable 12 and the rotation axis of the mirror 13 are located at a position 3 m (Z = 3 m) above the origin on FIG. There is an intersection, and the turning axis (x ′ axis) of the turntable 12 is a direction orthogonal to the paper surface of FIG. It is assumed that the rotation drive unit 14 is installed so as to be opposite to the mounting surface of the steel sheet S in the z-axis direction so that the blind spot region and the partial shadow region do not exist on the transport surface side in the z-axis direction. doing. As is apparent from a comparison of FIG. 10 with FIG. 8, when the rotation axis (x ′ axis) of the turntable 12 is perpendicular to the mounting surface (xy plane) of the steel sheet S, an error in the mirror rotation angle. It can be seen that the area of the region having a large influence increases.

  Therefore, the steel plate shape measuring device 5 is preferably set so that the rotation axis (x ′ axis) of the turntable 12 is parallel to the placement surface, but the turntable 12 is slightly inclined from parallel. A rotation axis (x ′ axis) may be set. Even if the rotation axis of the turntable 12 is inclined with respect to the mounting surface of the steel plate S, if the inclination angle of the x ′ axis with respect to the mounting surface is within 10 ° on the acute angle side, FIG. It has been confirmed that the same result as the examination result shown in FIG. 9 is obtained.

  Thus, in the steel plate shape correction device of the present embodiment, the steel plate shape is adjusted by adjusting the position of the region where the shadow ratio generated by providing the rotational drive unit 14 in the steel plate shape measuring device 5 is 25% or more. The laser beam of the measuring device 5 can be irradiated to accurately measure the steel plate shape on the conveying device before and after the shape correction and the steel plate shape below the press machine 1 during the shape correction, particularly under the pressure ram. That is, in the steel plate shape correction apparatus of the present embodiment, the press machine 1 and the steel plate are arranged so that the press machine 1 is not located in a region where the preset shadow ratio in the laser beam of the steel plate shape measuring device 5 is 25% or more. By installing the shape measuring device 5, it is possible to accurately measure the steel plate shape on the conveying device before and after the shape correction and the steel plate shape below the press machine 1 during the shape correction, particularly the pressure ram 2.

  Hereinafter, an example of a method for correcting the shape of the steel sheet S using the steel sheet shape correcting apparatus of the present invention according to FIG. 1 will be described. First, the steel plate S is transported into the shape measurement region A1 of the entrance bed 3, and the steel plate shape is measured by the steel plate shape measuring device 5 on the side of the entrance bed 3 in a state where the steel plate S is placed in the region A1. Measure. At this time, since the region B1 in which the shadow rate is 25% or more does not overlap with the shape measurement region A1, the shape measurement of the steel sheet can be performed with high accuracy in the region A1. The result of the shape measurement by the steel plate shape measuring device 5 on the side of the entrance bed 3 is recorded in the control device 6. Based on the recorded shape measurement result, the control device 6 determines the position (pressing position) of the steel sheet S to be pressed by the pressing ram 2 and the necessary pressing force at this position (pressing position). The pressurizing force required to correct this shape with respect to the measured shape is determined in advance for each steel type and thickness of the steel plate S.

  Next, the control device 6 conveys the steel plate S so that the pressurization position matches the position of the pressurization ram 2, and presses the pressurization ram 2 against the steel plate S with the necessary pressure to correct the shape. Immediately after performing the shape correction by the pressurization ram 2 on the pressurization position of the steel plate S, the control device 6 uses the steel plate shape measuring device 5 on the side of the exit bed 4 to shape the pressurization ram 2. The shape of the corrected part is measured. At this time, the measurement of the portion subjected to the shape correction is performed in a state where the portion is in the press machine 1. The shape measurement region A2 of the steel plate shape measuring device 5 on the side of the exit bed 4 includes the inside of the press 1, and the shape measurement region A2 includes a partial shadow region and a blind spot region in which the shadow rate is 25% or more. Therefore, it is possible to accurately measure the shape correction portion of the shape correction portion of the steel sheet S after the shape correction by the pressure ram 2 in a state where the portion is in the press 1. Then, based on the result of the shape measurement of the shape correction portion after shape correction, when the shape correction is sufficient, the steel sheet S is placed so that the other shape correction required portions are positioned under the pressure ram 2. Carry it forward and proceed with shape correction of other parts. When the shape measurement result of the shape correction site after correction is insufficient, the pressure ram 2 is pressed again on the site to perform shape correction. At this time, since the shape of the steel plate after the first shape correction can be measured without conveying the steel plate from the state where the first shape correction is performed, the time required for the shape correction can be shortened. In this case, the measurement mode of the steel plate shape measuring device 5 on the side of the exit bed 4 is preferably the press machine flatness measurement mode in which the turning angle is set to be small. By doing in this way, the shape measurement of the steel plate S in the press 1 can be performed in the minimum necessary time, and the measurement efficiency is improved.

  As described above, after the shape correction by the pressurization ram 2 is completed for all of the portions requiring shape correction, the control device 6 conveys the steel plate S to the exit bed 4 and places the steel plate S on the exit bed 4. In this state, the shape measurement device 5 on the side of the exit bed 4 performs shape measurement on the entire length of the steel sheet S, and finally determines the quality of the steel sheet S after shape correction. At this time, measurement is performed in the above-described full length flatness measurement mode. When the total length of the steel sheet S is short, the semi-long flatness measurement mode may be used.

  In addition, in embodiment shown in FIG. 1, the shape measurement area | region A1 of the steel plate shape measuring apparatus 5 of the side of the entrance bed 3 is made into the area | region on the entrance bed 3, and the steel plate shape of the side of the exit bed 4 is used. Although the shape measurement region A2 of the measuring device 5 is a region on the exit bed 4 and a region in the press 1, the present invention is not limited to this. As the shape measurement region A1 of the steel plate shape measuring device 5 on the side of the entrance bed 3, the steel plate shape measuring device 5 on the side of the entrance bed 3 as the region on the entrance bed 3 and the region in the press 1 is used. The shape of the steel sheet S in the press 1 may be measured. By doing in this way, while the steel plate shape measuring apparatus 5 of the side of the outgoing bed 4 is performing the shape measurement for the above-mentioned final shape quality determination, the next material in the press 1 The shape correction can be performed by the press machine 1 while the shape measurement is performed by the steel plate shape measuring device 5 on the side of the entrance bed 3.

  That is, for both the steel plate shape measuring device 5 on the side of the entrance bed 3 and the steel plate shape measuring device 5 on the side of the exit bed 4, the inside of the press 1 is used as a shape measurement region, so that the entrance bed The shape measurement of the steel plate S in the press 1 is performed using the steel plate shape measuring device 5 on which the shape measurement of the total length of the steel plate S on 3 and the shape measurement of the total length of the steel plate S on the exit bed 4 are not performed. Since it becomes feasible, the processing pitch can be shortened when the steel plate shape correction of the plurality of steel plates S is continuously performed.

  However, when the processing pitch is not taken into account, the measuring device 5 for the steel plate system in which the inside of the press machine 1 is the shape measurement region is either the side of the entrance bed 3 or the side of the exit bed 4. Also good.

  Moreover, in the said embodiment, although the steel plate shape measuring apparatus 5 is installed in both the side of the entrance bed 3 and the side of the exit bed 4, if the processing pitch is not taken into consideration, the entrance bed 3 You may make it install only in either one of the side and the side of the exit side bed 4.

1 Press machine 2 Pressure ram 3 Entrance bed (conveyor)
4 Delivery bed (conveying device)
DESCRIPTION OF SYMBOLS 5 Steel plate shape measuring apparatus 6 Control apparatus 7 Position detection apparatus 11 Light transmission / reception unit 12 Turntable 13 Galvano mirror 14 Rotation drive part

Claims (7)

A shape measurement region where a steel plate can be placed is set, and the surface of the steel plate placed on the shape measurement region is scanned with a laser beam to measure a predetermined group of detection points on the steel plate surface. A steel plate shape measuring device for measuring the shape of the steel plate from the distance measurement data,
A light transmission / reception unit, a laser beam emitted from the light transmission / reception unit is reflected and reflected to the steel sheet surface, and a mirror that reflects retroreflected light from the steel sheet surface to the light transmission / reception unit,
The steel plate shape measuring apparatus, wherein the shape measuring region is in a region where a shadow rate indicating a reduction rate of the amount of retroreflected light from the steel plate of the laser beam received by the mirror is less than 25%. . The mirror is rotatable around a first rotation axis coinciding with the optical axis of the laser light emitted from the light transmitting / receiving unit,
By changing the reflection direction of the laser light emitted from the light transmitting / receiving unit by the rotation of the mirror, the irradiation position of the laser light can be freely adjusted along a predetermined first direction in the steel plate surface. The steel plate shape measuring apparatus according to claim 1. A turntable that holds the light transmission / reception unit and the mirror and is rotatable about a second rotation axis orthogonal to the first rotation axis;
A rotation drive unit that rotates a turntable around the second rotation axis;
Have
The laser beam irradiation position can be freely adjusted along a second direction orthogonal to the first direction in the steel plate surface by the rotation of the turntable. Steel plate shape measuring device. The second rotation axis is
Not perpendicular to the steel sheet surface,
The A degree is 10 degrees or more, when an angle formed by the orthogonal projection of the second rotation axis to the plane parallel to the steel sheet surface with respect to the longitudinal direction of the steel sheet is A degree. 3. The steel sheet shape measuring apparatus according to 3. About orthographic projection of the second rotation axis onto a plane parallel to the steel plate surface,
When the angle formed by two straight lines at the end of the region where the shadow ratio is 25% or more is B degrees,
The steel sheet shape measuring apparatus according to claim 4, wherein the A degree is (B / 2) degree or more and 90 degree or less. However, B is greater than 0 and less than 180. The steel sheet shape measuring apparatus according to claim 4 or 5, wherein the A degree is 50 degrees to 70 degrees. In a steel plate shape correcting apparatus having a press machine provided with a pressure ram, and a transport device that is provided on the entry side and the exit side of the press machine and transports a steel material,
The steel plate shape measuring device according to any one of claims 1 to 6 is provided on the entry side and / or exit side of the press machine,
The shape measurement region is set to include at least one of the entrance side or the exit side conveying device,
A steel plate shape correction device, wherein a part of the shape measurement region of at least one of the steel plate shape measurement devices arranged on the entry side or the exit side is in the press machine.