JP6344290B2 - Planar shape measuring device - Google Patents

Description

  The present invention relates to a planar shape measuring apparatus.

  A planar shape measuring device for measuring the planar shape of a flat plate as a material to be rolled is installed on the entry side or the exit side of a rolling mill that rolls steel sheets. Patent Document 1 and Patent Document 2 propose a method of measuring a planar shape using a one-dimensional camera without stopping the transported flat plate in order to make the operation efficient. A one-dimensional camera is a camera in which light receiving elements that receive energy radiated from an imaging target are linearly arranged. When the object to be imaged is a slab or a high-temperature flat plate obtained by rolling the slab, the one-dimensional camera receives the radiant energy of the flat plate and outputs a signal having a luminance level corresponding to the magnitude of the received radiant energy. Therefore, if a one-dimensional camera is used, the boundary between the portion with and without the flat plate, that is, the edge of the flat plate can be detected based on the luminance level of the signal output from the camera.

  In the measurement methods proposed in the above patent documents, a one-dimensional camera is installed so that the field of view is parallel to the transport direction of the flat plate, and the field of view is scanned in a direction perpendicular to the transport direction. . By detecting the edges on both sides of the flat plate from the image data obtained by the one-dimensional camera, the length of the flat plate can be measured from the distance between the edges. Patent Document 2 also discloses that a one-dimensional camera is installed so that the field of view is perpendicular to the transport direction of the flat plate, and the field of view is scanned in a direction parallel to the transport direction. According to this, the edges on both sides of the flat plate can be detected, and the width of the flat plate can be measured from the distance between the edges. Furthermore, in each of the above-mentioned patent documents, two cameras for length measurement or width measurement are installed side by side, and the tilt angle and the bending of the flat plate are determined from the imaging data of the two cameras obtained by scanning. Is disclosed.

Japanese Patent Laid-Open No. 10-103927 Japanese Patent Laid-Open No. 11-44516

  However, the measurement methods proposed in the above patent documents have room for improvement in terms of measurement accuracy as described below.

  The relationship between the surface temperature of the flat plate captured by the camera and the brightness level of the captured image obtained by the camera is determined by the setting of parameters that determine the light receiving characteristics of the camera, such as the iris value and exposure time. Since there is an upper limit on the luminance level of the signal output from the camera, it is necessary to set parameters in accordance with the assumed surface temperature of the flat plate in order to implement the measurement methods proposed in the above patent documents. The The brightness level of the captured image when a high-temperature flat plate is imaged by the camera changes sensitively with respect to the surface temperature of the flat plate. For example, when the luminance level when the surface temperature is 700 ° C. is used as a reference, the relative ratio of the luminance level when the surface temperature is 800 ° C. is 5 times, and the relative ratio of the luminance level when the surface temperature is 900 ° C. Will be 18 times. For this reason, when the actual temperature of the flat plate is too high than the assumed temperature, the luminance level of the captured image may reach the upper limit value. Even if the luminance level does not reach the upper limit, the luminance level at the boundary between the portion without the flat plate and the portion with the flat plate may increase, and as a result, the edge may not be detected accurately. Conversely, if the actual flat plate temperature is too low than the expected temperature, the brightness level of the portion with the flat plate will be low, resulting in an ambiguous boundary with the portion without the flat plate, so that the edge cannot be detected accurately. There is a fear.

  Further, in the method of measuring the planar shape of the flat plate by scanning the visual field of the one-dimensional camera, it is difficult to eliminate the influence of the movement or rotation of the flat plate while scanning the visual field. For this reason, it is not possible to accurately measure bending of a flat plate, deformation of squareness, and the like.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a planar shape measuring apparatus that can accurately measure the planar shape of a flat plate conveyed by a rolling line.

The planar shape measuring apparatus according to the present invention is a two-dimensional camera that images a flat plate conveyed by a rolling line, a temperature information detection device that detects temperature information of the flat plate, a parameter that determines the light receiving characteristics of the two-dimensional camera, The parameter setting is determined based on the storage device storing the correspondence with the temperature of the flat plate, the temperature information detected by the temperature information detection device, and the correspondence, and the determined parameter setting is stored in the two-dimensional camera. In a planar shape measuring device comprising: a parameter setting commanding device for commanding and a profile value computing device for computing a profile value for specifying a planar shape of a flat plate from image data obtained by a two-dimensional camera ; The parameter setting command device further includes a receiving device, the temperature information received by the receiving device, and the temperature information detected by the temperature information detecting device. Based on the correspondence relationship, it determines the configuration parameters, the setting of the determined parameter is to features that you command to the two-dimensional camera.
In addition, the planar shape measuring apparatus according to the present invention includes a two-dimensional camera that images a flat plate conveyed on a rolling line, a temperature information detection device that detects temperature information of the flat plate, and a parameter that determines the light receiving characteristics of the two-dimensional camera. And the storage device storing the correspondence relationship between the temperature of the flat plate, the temperature information detected by the temperature information detection device, and the correspondence relationship, the parameter setting is determined, and the determined parameter setting is two-dimensional In the planar shape measuring device, comprising: a parameter setting command device that commands the camera; and a profile value computing device that computes a profile value that specifies the planar shape of the flat plate from the image data captured by the two-dimensional camera. Whether the image data of a one-dimensional camera having a linear field of view perpendicular to the conveyance direction of the flat plate and the flat plate imaged by the one-dimensional camera A luminance level calculation device that calculates the luminance level of a captured image of a flat plate, and the field of view of the one-dimensional camera and the field of view of the two-dimensional camera are adjacent to each other, and the two-dimensional A plate presence / absence detection device that detects that a flat plate has entered the field of view of the camera, and an image that instructs the two-dimensional camera to take an image when the plate presence / absence detection device detects that a flat plate has entered the field of view of the two-dimensional camera And a command device.

  According to the present invention, it is possible to accurately measure the planar shape of a flat plate conveyed on a rolling line.

It is a block diagram which shows the planar shape measuring apparatus of Embodiment 1 of this invention. It is a figure for demonstrating the detection method of the flat plate using the width direction imaging device. It is a figure for demonstrating the detection method of the flat plate using the width direction imaging device. It is a figure which shows the operation | movement flow of the planar shape measuring apparatus shown in FIG. It is a figure which shows an example of the relationship between the surface temperature of a flat plate, and the luminance level of a captured image. It is a table | surface which shows an example of the relative ratio of the luminance level with respect to the reference temperature for every surface temperature. It is a figure which shows an example of the setting of the exposure time of the camera with respect to the surface temperature of a flat plate. It is a planar shape measuring apparatus of Embodiment 2 of this invention. It is a figure for demonstrating the function of a peak hold processing apparatus. It is a figure for demonstrating the function of a peak hold processing apparatus. It is a figure which shows the operation | movement flow of the planar shape measuring apparatus shown in FIG. It is a planar shape measuring apparatus of Embodiment 3 of this invention. It is a figure for demonstrating the operation | movement at the time of imaging of the planar shape measuring apparatus shown in FIG. It is a figure which shows the operation | movement flow of the planar shape measuring apparatus shown in FIG.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the same code | symbol is attached | subjected to the element which is common in each figure, and the overlapping description is abbreviate | omitted.

Embodiment 1 FIG.
FIG. 1 is a configuration diagram showing a planar shape measuring apparatus according to Embodiment 1 of the present invention. The planar shape measuring apparatus 1 according to the first embodiment shown in FIG. 1 transports the planar shape of the transported flat plate 100 without stopping the flat plate in a hot rolling line for hot rolling the flat plate (steel plate) 100. It is a device that measures in the state. In the following description, the longitudinal direction of the flat plate 100 is referred to as the length direction, and the direction perpendicular to both the longitudinal direction and the thickness direction of the flat plate 100 is referred to as the width direction (or plate width direction). The flat plate 100 is transported so that the longitudinal direction is substantially parallel to the transport direction. The planar shape measuring apparatus 1 according to the first embodiment measures the planar shape of the flat plate 100 on the entry side or the exit side of the rough rolling mill, for example. The dimensions of the flat plate 100 (slab) before being rolled are, for example, about 2000 mm in length, about 1000 mm in width, and about 300 mm in thickness.

  As shown in FIG. 1, the planar shape measuring apparatus 1 of the present embodiment includes a planar shape imager 8. The planar shape imager 8 is a two-dimensional camera having a two-dimensional field of view. The planar shape image pickup device 8 includes an image pickup device that converts an image that is an optical signal into electricity. As the imaging device, for example, a CCD area image sensor, a CMOS area image sensor, or the like can be used. The field of view of the planar imaging device 8 includes a region through which the flat plate 100 passes. The planar shape imager 8 images the planar shape of the flat plate 100 from above. The planar imaging device 8 captures a planar still image of the flat plate 100. Even if the flat plate 100 is moving, the planar image pickup device 8 can capture a planar still image of the flat plate 100 by relatively shortening the exposure time. The planar imaging device 8 is installed at a height of, for example, about 20 m to 25 m from the position of the flat plate 100. The field of view of the planar imaging device 8 has a width of about 7 m in length and about 6 m in width at the height through which the flat plate 100 passes.

  The planar shape measuring apparatus 1 includes a width direction imager 7. The width direction image pickup device 7 is a one-dimensional camera having a linear field of view. The width direction image pickup device 7 includes an image pickup device such as a CCD linear image sensor or a CMOS linear image sensor. The visual field of the width direction image pickup device 7 is set to be perpendicular to the conveyance direction of the flat plate 100. The visual field of the width direction image pickup device 7 is adjacent to the upstream side in the transport direction with respect to the visual field of the planar shape image pickup device 8.

  The functions of the following apparatuses constituting the planar shape measuring apparatus 1 can be realized by a processor executing a program stored in a memory in a computer. Multiple sets of processors and memories may work together.

  The planar shape measuring device 1 includes a measurement start command receiving device 3. The measurement start command receiving device 3 receives a measurement start command transmitted from the outside. An apparatus (not shown) that transmits a measurement start command transmits a measurement start command so as to synchronize with the timing at which the flat plate 100 is conveyed within the field of view of the planar image pickup device 8. For example, the apparatus transmits a measurement start command at a timing calculated based on the conveyance speed and the conveyance pitch of the flat plate 100.

  The planar shape measuring apparatus 1 uses the width direction imaging device 7 for detecting the flat plate 100. The planar shape measuring apparatus 1 includes a measurement start timing generating device 4 and a plate presence / absence detecting device 17. Hereinafter, a detection method of the flat plate 100 using the width direction image pickup device 7 will be described with reference to FIGS. 2 and 3.

  As shown by a rectangular frame in FIG. 2, a measurement range 28 for measuring the planar shape of the flat plate 100 is determined in advance on the line on which the flat plate 100 is conveyed. The measurement range 28 corresponds to the visual field of the planar shape imager 8. The visual field 27 of the width direction image pickup device 7 is in the vicinity (nearest) on the upstream side in the transport direction with respect to the measurement range 28 (the visual field of the planar image pickup device 8). When the flat plate 100 is at the position 100a upstream of the measurement range 28 and the visual field 27 in the transport direction, a measurement start command is transmitted from an external device. When the measurement start command receiving device 3 receives a measurement start command from the outside, the command is sent to the measurement start timing generating device 4. In response to the measurement start command, the measurement start timing generator 4 issues a measurement command to the width direction image pickup device 7. In response to the measurement command, the width direction image pickup device 7 starts imaging.

  The plate presence / absence detection device 17 detects that the flat plate 100 has entered the measurement range 28 based on the luminance level of the imaging data of the width direction imaging device 7. A graph (a) in FIG. 3 is an example of an imaging signal of the width-direction imaging device 7 when the flat plate 100 is at a position 100 a upstream of the measurement range 28 and the visual field 27. In the graph (a), the luminance level at any position in the plate width direction does not exceed the plate presence detection threshold level. The plate presence detection threshold level is set to a level at which the luminance level when the flat plate 100 is in the visual field and the luminance level when the flat plate 100 is not present can be clearly distinguished. In this case, the plate presence / absence detection device 17 outputs a plate no signal indicating that the flat plate 100 is not detected.

  The transported flat plate 100 eventually enters the measurement range 28. A graph (b) in FIG. 3 is an example of an imaging signal of the width direction imaging device 7 when the flat plate 100 is at a position 100 b (see FIG. 2) on the way to the measurement range 28. In the graph (b), the luminance level at the center in the plate width direction exceeds the plate presence detection threshold level. In this case, the plate presence / absence detection device 17 outputs a plate presence signal indicating that the flat plate 100 is detected.

  The transported flat plate 100 eventually completely enters the measurement range 28. A graph (c) in FIG. 3 is an example of an image pickup signal of the width direction image pickup device 7 when the flat plate 100 completely enters the measurement range 28. In the graph (c), the luminance level at any position in the plate width direction does not exceed the plate presence detection threshold level. In this case, the plate presence / absence detection device 17 outputs a plate no signal indicating that the flat plate 100 is not detected.

  When the signal output from the plate presence / absence detecting device 17 changes from a plate presence signal detecting the flat plate 100 to a plate no signal not detecting the flat plate 100, the measurement start timing generating device 4 To start measurement. In response to the measurement start command, the planar shape imager 8 captures a still image of the flat plate 100 and collects the captured image data.

  The planar shape measuring device 1 processes the image data obtained by the imaging by the planar shape imager 8 in order to process the width edge coordinate computing device 9a, the length edge coordinate computing device 9b, the edge coordinate width computing device 10a, the edge Inter-coordinate length computing device 10b, width edge central coordinate computing device 11a, length edge central coordinate computing device 11b, tilt angle computing device 12, width profile computing device 13, length direction curved shape computing device 14, length profile computing The apparatus 15 and the width direction bending shape calculating apparatus 16 are provided. These devices constitute a profile value calculation device that calculates a profile value that specifies the planar shape of the flat plate 100.

  The width edge coordinate calculation device 9 a detects the edge of the flat plate 100 by performing image processing on the captured image captured by the planar shape imager 8, and calculates the edge coordinates for measuring the width of the flat plate 100. The length edge coordinate calculation device 9b detects an edge of the flat plate 100 by performing image processing on the captured image captured by the planar shape image pickup device 8, and calculates an edge coordinate for measuring the length of the flat plate 100.

  The edge coordinate width calculation device 10a calculates the width of the flat plate 100 by calculating the interval between the rising edge coordinate and the falling edge coordinate based on the calculation result of the width edge coordinate calculation device 9a. The length calculation unit 10b between the edge coordinates calculates the length of the flat plate 100 by calculating the interval between the rising edge coordinate and the falling edge coordinate based on the calculation result of the length edge coordinate calculation unit 9b.

  The width edge center coordinate calculation device 11 a calculates the median value of the rising edge coordinate and the falling edge coordinate along the length direction of the flat plate 100 based on the calculation result of the width edge coordinate calculation device 9 a. The length edge center coordinate calculation device 11 b calculates the median value of the rising edge coordinate and the falling edge coordinate along the width direction of the flat plate 100 based on the calculation result of the length edge coordinate calculation device 9 b.

  The inclination angle calculation device 12 calculates the inclination angle of the flat plate 100 (the rotation angle of the flat plate 100 with respect to the normal direction) based on the calculation results of the width edge central coordinate calculation device 11a and the length edge central coordinate calculation device 11b.

  The width profile calculation device 13 corrects the verification result of the inter-edge coordinate width calculation device 10 a based on the calculation result of the tilt angle calculation device 12, thereby determining how the width of the flat plate 100 is along the length direction of the flat plate 100. Is calculated (hereinafter referred to as “width profile”). The length profile calculation device 15 corrects the verification result of the inter-edge coordinate length calculation device 10b based on the calculation result of the tilt angle calculation device 12, so that the length of the flat plate 100 extends along the width direction of the flat plate 100. A profile indicating how it changes (hereinafter referred to as “length profile”) is calculated.

  The length direction bending shape calculation device 14 corrects the verification result of the width edge central coordinate calculation device 11 a based on the calculation result of the tilt angle calculation device 12, so that the center position of the width of the flat plate 100 is the length of the flat plate 100. A profile (hereinafter referred to as a “longitudinal bent shape”) indicating how it is bent along the direction is calculated. The width direction bending shape calculation device 16 corrects the verification result of the length edge central coordinate calculation device 11b based on the calculation result of the tilt angle calculation device 12, so that the center position of the length of the flat plate 100 is the width of the flat plate 100. A profile (hereinafter referred to as “width-direction bent shape”) indicating how it is bent along the direction is calculated.

  The width profile calculation device 13, the length direction bending shape calculation device 14, the length profile calculation device 15, and the width direction bending shape calculation device 16 are examples of a distortion calculation device that calculates data related to the planar shape distortion of the flat plate 100. . In the planar shape measuring apparatus 1 according to the first embodiment, these distortion calculation devices are provided, so that the planar shape distortion of the flat plate 100 such as the deformation of the squareness of the flat plate 100 and the bending of the center line of the flat plate 100 is performed. It can be measured accurately.

  Here, FIG. 5 shows an example of how the brightness level of the captured image changes depending on the surface temperature of the flat plate 100 when the parameter value for determining the light receiving characteristic of the camera is fixed. The vertical axis of the graph shown in FIG. 5 represents the relative ratio of the luminance level of each surface temperature on the logarithmic axis when the luminance level when the surface temperature is 700 ° C. is used as a reference. The horizontal axis of the graph shown in FIG. 5 is the surface temperature of the flat plate 100. From this graph, it can be seen that the luminance level changes sensitively with respect to the surface temperature of the flat plate 100 on the horizontal axis. FIG. 6 summarizes the relationship between the surface temperature and the luminance level of the flat plate 100 shown in FIG. 5 in a table. This table lists the relative ratio of the luminance level to the reference temperature for each surface temperature for various reference temperatures. For example, the relative ratio of the luminance level at 800 ° C. when 700 ° C. is the reference temperature is 5. This means that if the upper limit value of the luminance level is set based on 700 ° C., when the actual surface temperature is 800 ° C., the upper limit of 500% of light is received. As described above, it is difficult to detect an edge from a captured image in which the luminance level greatly exceeds the upper limit value. Conversely, it is also difficult to detect an edge from a captured image whose luminance level is too low with respect to the upper limit value. The brightness level of the captured image can be adjusted by changing the parameter value that determines the light receiving characteristics. Therefore, in order to accurately detect the edge from the captured image, it is desirable that the parameter value is an appropriate value in relation to the surface temperature of the transported flat plate 100.

  The planar shape measuring apparatus 1 according to the present embodiment adjusts the exposure time of the width direction image pickup device 7 and the planar shape image pickup device 8 so that the brightness level of the picked-up image is appropriately set regardless of the surface temperature of the flat plate 100. It shall be The planar shape measuring device 1 includes a flat plate temperature information receiving device 2, an exposure time table storage device 5, and an exposure time setting command device 6. The flat plate temperature information receiving device 2 receives surface temperature information regarding the flat plate 100 transmitted from the outside. A device (not shown) that transmits surface temperature information measures the surface temperature of the flat plate 100 with a thermometer (for example, a radiation thermometer) arranged upstream of the planar shape measuring device 1, and transmits the temperature measurement value as surface temperature information. To do. Alternatively, the surface temperature is calculated using a temperature model based on the heat balance in the conveyance section from the thermometer to the planar shape measuring apparatus 1, and the calculated temperature value is transmitted as surface temperature information.

  The exposure time table storage device 5 stores an exposure time table that associates the exposure times of the width direction image pickup device 7 and the planar shape image pickup device 8 with the surface temperature of the flat plate 100. The exposure time is an example of a parameter that determines the light receiving characteristics of the cameras (width direction image pickup device 7 and planar shape image pickup device 8). An image of the exposure time table is shown in FIG. In the exposure time table shown in FIG. 7, the exposure time is shortened as the surface temperature of the flat plate 100 is higher. The exposure time setting command device 6 sets the exposure time based on the surface temperature information received by the flat plate temperature information receiving device 2 and the correspondence defined by the exposure time table, and the width direction image pickup device 7 and the planar shape image pickup device. 8 is commanded. The width direction image pickup device 7 and the planar shape image pickup device 8 set the exposure time in accordance with a command from the exposure time setting command device 6.

  In the present invention, for example, an iris value (F value) may be controlled as a parameter for determining the light receiving characteristics of the cameras (the width direction image pickup device 7 and the planar shape image pickup device 8) instead of the exposure time. That is, as the surface temperature of the flat plate 100 is higher, the iris value (F value) may be increased to adjust the aperture of the camera. Compared to an iris value that requires mechanical adjustment, the exposure time that only requires electrical adjustment is more responsive. The parameters that determine the light reception characteristics of the camera include a shutter speed, an exposure value, and the like.

  As described above, the luminance level of the captured image changes sensitively with respect to the surface temperature of the flat plate 100. As a brightness level of the captured image, a desirable mode is a captured image in which the brightness level is saturated but not supersaturated, or a captured image in which the brightness level is not saturated and is not too low.

  For example, it is assumed that the surface temperature information received from the outside is 700 ° C. due to some factor even though the actual surface temperature of the flat plate 100 is 800 ° C. In this case, if the exposure time of the planar image pickup device 8 is set so that the luminance level at 700 ° C. is 100% of the upper limit value, the flat shape image pickup device 8 has 500% of the upper limit value of the luminance level. The light will be received. As a result, the captured image of the planar shape image pickup device 8 is in a state where the luminance level is supersaturated. In a captured image with a supersaturated luminance level, the image signal of the portion without the flat plate 100 is lifted, making it difficult to calculate the exact coordinates of the edge, and accurately measuring the planar shape of the flat plate 100. difficult.

  For this reason, it is desirable that the exposure time set by the exposure time table is set so that the luminance level is about 80% with respect to the surface temperature information. However, for example, it is assumed that the surface temperature information received from the outside is 800 ° C. due to some factor even though the actual surface temperature of the flat plate 100 is 700 ° C. In this case, if the exposure time of the planar imaging device 8 is set so that the luminance level at 800 ° C. is 80% of the upper limit value, the light received by the planar imaging device 8 is the upper limit value of the luminance level. It is reduced to 1/5 of 80%, that is, 16%. As a result, the brightness level of the captured image of the planar image pickup device 8 is too low. In a captured image whose luminance level is too low, since the difference between the luminance level of the portion where the flat plate 100 is present and the luminance level of the portion where the flat plate 100 is absent is small, it becomes difficult to calculate the exact coordinates of the edge. It is difficult to measure the shape accurately.

  In view of the matters as described above, the planar shape measuring apparatus 1 of the present embodiment further includes a luminance level calculation device 18. The luminance level calculation device 18 samples the imaging signal from the imaging data of the width direction imaging device 7 and calculates the luminance level of the captured image. The brightness level of the captured image of the width direction image pickup device 7 can be used as surface temperature information of the flat plate 100. The exposure time setting command device 6 adjusts the exposure time settings of the width direction image pickup device 7 and the planar shape image pickup device 8 based on the luminance level calculated by the luminance level calculation device 18. For example, the exposure time setting command device 6 estimates the actual surface temperature of the flat plate 100 from the luminance level calculated by the luminance level calculation device 18, and refers to the exposure time table for the exposure time suitable for the estimated surface temperature. decide. The exposure time setting command device 6 estimates the actual surface temperature of the flat plate 100 based on the luminance level calculated by the luminance level calculation device 18 and the surface temperature information received by the flat plate temperature information receiving device 2. good. Alternatively, the exposure time setting command device 6 may shorten the exposure time by applying a predetermined reduction coefficient to the currently set exposure time when the brightness level of the captured image reaches the upper limit value and is oversaturated. . Further, when the brightness level of the captured image is too low, the exposure time setting command device 6 may extend the exposure time by applying a predetermined increase coefficient to the currently set exposure time.

  After the surface temperature of the flat plate 100 temporarily decreases due to contact with a roll of a rolling mill, water cooling, or the like, the surface temperature of the flat plate 100 may increase again due to the recuperation effect due to heat conduction from the inside of the flat plate 100. . For this reason, the surface temperature of the flat plate 100 may change from moment to moment. Therefore, it may be difficult to accurately predict the surface temperature of the flat plate 100 when the planar image pickup device 8 images the flat plate 100 based on the surface temperature information of the flat plate 100 received from the outside.

  The planar shape measuring apparatus 1 according to the present embodiment images the flat plate 100 with the width direction imaging device 7 immediately before the planar shape image pickup device 8 picks up the flat plate 100 and calculates the luminance level of the obtained image. The exposure time setting of the planar image pickup device 8 is adjusted. According to such a configuration, even when the error in the surface temperature information of the flat plate 100 from the outside is large, it is possible to obtain a captured image with appropriate brightness without being too bright and not too dark, and the accurate coordinates of the edge can be obtained. The length and width can be accurately measured by calculation.

  The exposure time set for the planar image pickup device 8 is normally set within a range of about 1 μsec to 10 msec. Therefore, even if the planar imaging device 8 captures an image while the flat plate 100 is moving, the collected captured image can obtain an image equivalent to a still image. For this reason, the influence of the image distortion due to the movement of the flat plate 100 on the measurement result is in a negligible range.

Next, an example of the operation flow of the planar shape measuring apparatus 1 according to the first embodiment will be described with reference to the flowchart shown in FIG.
Step S101: The flat plate temperature information receiving device 2 receives surface temperature information regarding the flat plate 100 transmitted from the outside of the device.
Step S102: The exposure time setting command device 6 refers to the exposure time table stored in the exposure time table storage device 5, and corresponds to the surface temperature information received by the flat plate temperature information receiving device 2 in the width direction image pickup device 7. And the exposure time of the planar image pickup device 8 is acquired.
Step S103: The exposure time setting command device 6 sets the exposure time acquired in step S102 for the width direction image pickup device 7.

Step S104: The measurement start command receiving device 3 receives a measurement start command transmitted from the outside of the device.
Step S105: The measurement start timing generator 4 instructs the width direction image pickup device 7 to prepare for detecting the timing to start measurement.
Step S106: When the flat plate 100 enters the visual field 27 of the width direction image pickup device 7, the plate presence / absence detection device 17 detects the presence of the plate from the image pickup signal of the width direction image pickup device 7.

Step S107: The luminance level calculation device 18 samples the luminance level of the imaging signal of the width direction image pickup device 7 and calculates the luminance level.
Step S108: When the entire flat plate 100 enters the field of view (measurement range 28) of the planar image pickup device 8, the plate presence / absence detection device 17 detects the absence of the plate from the image pickup signal of the width direction image pickup device 7.
Step S109: The exposure time setting command device 6 refers to the exposure time table based on the calculation result of the luminance level calculation device 18, and sets an appropriate exposure time for the planar image pickup device 8.

Step S110: When the plate presence / absence detection device 17 detects the absence of a plate, the measurement start timing generation device 4 instructs the planar shape image pickup device 8 to start the measurement. The planar shape imager 8 collects a planar shape captured image of the flat plate 100 moving in the field of view (measurement range 28).
Step S111: The width edge coordinate calculation device 9a calculates edge coordinates for measuring the width of the flat plate 100 from the imaging result of the planar shape image pickup device 8. The length edge coordinate calculation device 9 b calculates edge coordinates for measuring the length of the flat plate 100 from the imaging result of the planar shape imager 8.

Step S112: The edge coordinate width calculation device 10a calculates the width of the flat plate 100 by calculating the interval between the rising edge coordinate and the falling edge coordinate calculated by the width edge coordinate calculation device 9a.
Step S113: The width edge center coordinate calculation device 11a calculates the median value of the rising edge coordinates and the falling edge coordinates calculated by the width edge coordinate calculation device 9a along the length direction of the flat plate 100.
Step S114: The edge coordinate length calculation device 10b calculates the length of the flat plate 100 by calculating the interval between the rising edge coordinate and the falling edge coordinate calculated by the length edge coordinate calculation device 9b.
Step S115: The length edge central coordinate calculation device 11b calculates the median value of the rising edge coordinate and the falling edge coordinate calculated by the length edge coordinate calculation device 9b along the width direction of the flat plate 100.

Step S116: The tilt angle calculation device 12 calculates the tilt angle of the flat plate 100 based on the coordinates of a plurality of points calculated by the width edge central coordinate calculation device 11a.
Step S117: The tilt angle calculation device 12 calculates the tilt angle of the flat plate 100 based on the coordinates of a plurality of points calculated by the length edge central coordinate calculation device 11b.

Step S118: The width profile calculation device 13 calculates the width profile of the flat plate 100 by correcting the verification result of the edge coordinate width calculation device 10a using the tilt angle calculated by the tilt angle calculation device 12.
Step S119: The length direction bending shape calculation device 14 uses the inclination angle calculated by the inclination angle calculation device 12 to correct the verification result of the width edge central coordinate calculation device 11a, so that the length direction of the flat plate 100 is corrected. Calculate the bend shape.
Step S120: The length profile calculation device 15 uses the inclination angle calculated by the inclination angle calculation device 12 to correct the verification result of the inter-edge coordinate length calculation device 10b, thereby obtaining the length profile of the flat plate 100. Calculate.
Step S121: The width direction bend shape calculation device 16 corrects the verification result of the length edge central coordinate calculation device 11b using the tilt angle calculated by the tilt angle calculation device 12, thereby bending the flat plate 100 in the width direction. Calculate the shape.

  In the planar shape measuring apparatus 1 according to the present embodiment, a flat plate is obtained by a tilt angle calculation device 12 from an imaged image corresponding to a still image captured by a single two-dimensional camera (planar shape imager 8) within a short exposure time. Since 100 tilt angles are calculated, the tilt angle can be measured accurately. Therefore, according to this Embodiment, the width profile of a flat plate 100, a length direction bending shape, a length profile, and a width direction bending shape can be measured correctly.

  On the other hand, the flat plate 100 is imaged by simultaneously scanning two one-dimensional cameras for width measurement having a field of view in a direction perpendicular to the flat plate conveyance direction, and the inclination angle of the flat plate 100 is calculated from these captured images. In such a case, the width profile of the flat plate 100 may not be accurately measured because of the influence of the squareness deformation of the flat plate 100 and the influence of the movement of the flat plate 100 during imaging. There is a possibility that the bending shape in the vertical direction cannot be measured accurately. In addition, the flat plate 100 is imaged by simultaneously scanning two one-dimensional cameras for length measurement having a field of view in a direction parallel to the flat plate conveyance direction, and the inclination angle of the flat plate 100 is calculated from these captured images. In such a case, the length profile of the flat plate 100 may not be accurately measured because it is affected by the deformation of the flat plate 100 and the movement of the flat plate 100 during imaging. The direction bending shape may not be measured accurately.

  In the present embodiment, the exposure time setting command device 6 has a function as a parameter setting command device for setting parameters for determining the light receiving characteristics of the planar shape image pickup device 8. Further, the width direction image pickup device 7 and the luminance level calculation device 18 have a function as a temperature information detection device that detects surface temperature information of the flat plate 100. In the present invention, the surface temperature of the flat plate 100 is measured with a radiation thermometer (not shown) immediately before the flat image pickup device 8 images the flat plate 100, and the exposure time of the flat shape image pickup device 8 is determined based on the measurement result. The parameters may be adjusted. The planar shape measuring apparatus 1 according to the first embodiment includes the flat plate temperature information receiving device 2, but in the present invention, the flat plate temperature information receiving device 2 may be omitted. In the present invention, the parameter setting command device determines the light receiving characteristics of the planar image pickup device 8 based on the surface temperature information of the flat plate 100 detected by the temperature information detection device without receiving the surface temperature information from the outside. May be set.

Embodiment 2. FIG.
Next, the second embodiment of the present invention will be described with reference to FIG. 8 to FIG. 11. However, the difference from the first embodiment will be mainly described, and the same parts or corresponding parts are denoted by the same reference numerals. The description is omitted.

  FIG. 8 is a configuration diagram illustrating a planar shape measuring apparatus according to the second embodiment of the present invention. In addition to the configuration of the first embodiment, the planar shape measuring apparatus 1 of the second embodiment shown in FIG. 8 includes a peak hold processing device 19 that holds the maximum value of the luminance level of the imaging data of the width direction imaging device 7. Further prepare. The peak hold processing device 19 continues to hold the maximum value of the luminance level of the image data of the width direction image pickup device 7 while the plate presence / absence detection device 17 detects that the flat plate 100 is present. The luminance level calculation device 18 calculates the luminance level of the imaging data of the width direction image pickup device 7 that has been peak-holded by the peak hold processing device 19 while the plate presence / absence detection device 17 detects that the flat plate 100 is present. Calculate. The peak hold processing device 19 has a function of holding the highest temperature information among the temperature information at a plurality of locations detected by the width direction image pickup device 7.

  With reference to FIGS. 9 and 10, the function of the peak hold processing device 19 will be further described. When the flat plate 100 is not cooled with water and is naturally air-cooled, the temperature at the center tends to be higher and the temperature at the end tends to be lower than that at the center, and the temperature distribution is smoothed. It has been a gentle change. The graph in FIG. 9 is a graph showing a change in the luminance level of the imaging data of the width direction image pickup device 7 when the flat plate 100 in such a state passes through the visual field 27 of the width direction image pickup device 7. The luminance level of this graph is the luminance level at the center position in the width direction of the flat plate 100 (the AA position in FIG. 9). The position on the horizontal axis of this graph corresponds to the position in the length direction of the flat plate 100 shown on the graph. In the case shown in FIG. 9, the surface level of the flat plate 100 is obtained by sampling the luminance level during a state in which the plate presence / absence detection device 17 detects that the flat plate 100 is present, and calculating an average value thereof. Temperature can be detected accurately.

  In the hot rolling line, the flat plate 100 is cooled with water. The surface temperature of the portion where the cooling water is poured may be temporarily lowered. The graph (a) in FIG. 10 shows the brightness level of the imaging data of the width direction image pickup device 7 when the flat plate 100 whose surface temperature is locally lowered by the cooling water passes through the visual field 27 of the width direction image pickup device 7. It is a graph which shows the change of. The luminance level of the graph (a) is the luminance level at the center position in the width direction of the flat plate 100 (the AA position in FIG. 10). The position on the horizontal axis of the graph (a) corresponds to the position in the length direction of the flat plate 100 shown on the graph (a).

  As shown in FIG. 10, in the portion where the surface temperature of the flat plate 100 is locally lowered due to the influence of water cooling, a drop also occurs in the luminance level of the imaging data of the width direction imaging device 7. When the brightness level of the imaging data of the width direction image pickup device 7 is sampled at a plurality of positions as shown in the graph (a) and the surface temperature of the flat plate 100 is calculated by a method of calculating the average value thereof, As a result, the calculation result is affected by the general drop, and there is a problem that an appropriate exposure time of the planar image pickup device 8 cannot be set. That is, when the surface temperature of the flat plate 100 is calculated to be lower than the actual temperature, the exposure time of the planar image pickup device 8 is set longer than an appropriate value.

  A graph (b) in FIG. 10 is a graph showing a change in the luminance level of the imaging data of the width direction image pickup device 7 subjected to the peak hold processing by the peak hold processing device 19. The peak hold processing device 19 samples the luminance levels at a plurality of positions at the AA position during the state in which the plate presence / absence detecting device 17 detects the presence of the flat plate 100, and obtains the maximum value of the sampled luminance levels. Hold. That is, the peak hold processing device 19 peaks the luminance level in the conveyance direction of the flat plate 100 based on the imaging signal of the width direction image pickup device 7.

  The luminance level calculation device 18 calculates the luminance level of the imaging data of the width direction image pickup device 7 that has been peak-holded by the peak hold processing device 19 while the plate presence / absence detection device 17 detects that the flat plate 100 is present. Calculate. Thereby, the surface temperature information of the flat plate 100 of the part except the part in which the surface temperature of the flat plate 100 fell locally under the influence of water cooling can be detected accurately. As a result, the exposure time of the planar image pickup device 8 can be set appropriately.

  Next, an example of the operation flow of the planar shape measuring apparatus 1 according to the second embodiment will be described with reference to the flowchart shown in FIG. 11. The difference from the operation flow according to the first embodiment (FIG. 4) will be mainly described. The description of the same points is omitted. The operation flow of the second embodiment is the same as the operation flow of the first embodiment except that step S130 and step S131 are provided in place of step S107 of the operation flow of the first embodiment (FIG. 4). As shown in FIG. 11, the operation flow of the second embodiment includes steps executed in the order of step S106, step S130, step S131, and step S108.

  In step S106, when the flat plate 100 enters the field of view 27 of the width direction image pickup device 7 and the plate presence / absence detection device 17 detects the presence of a plate from the image pickup signal of the width direction image pickup device 7, the planar shape of the second embodiment. The measuring device 1 performs the following operation.

Step S130: The peak hold processing device 19 processes the image pickup signal of the width direction image pickup device 7 so as to peak-hold the luminance level in the conveyance direction of the flat plate 100.
Step S131: The luminance level calculation device 18 calculates the luminance level of the imaging data of the width direction image pickup device 7 that has been subjected to the peak hold processing by the peak hold processing device 19.
Step S108: When the entire flat plate 100 enters the field of view (measurement range 28) of the planar image pickup device 8, the plate presence / absence detection device 17 detects the absence of the plate from the image pickup signal of the width direction image pickup device 7.
Step S109: The exposure time setting command device 6 refers to the exposure time table based on the calculation result of the luminance level calculation device 18, and sets an appropriate exposure time for the planar image pickup device 8.

  In the second embodiment, the exposure time setting command device 6 is based on the calculation result obtained by the luminance level calculation device 18 calculating the luminance level of the imaging data of the width direction image pickup device 7 subjected to the peak hold processing by the peak hold processing device 19. Set the exposure time. For this reason, a more appropriate exposure time can be set for the planar image pickup device 8 without being affected by a local decrease in surface temperature due to water cooling of the flat plate 100. In the second embodiment, the width direction image pickup device 7, the luminance level calculation device 18, and the peak hold processing device 19 have a function as a temperature information detection device that detects surface temperature information of the flat plate 100.

Embodiment 3 FIG.
Next, the third embodiment of the present invention will be described with reference to FIG. 12 to FIG. 14. The description will focus on the differences from the first embodiment described above, and the same or corresponding parts will be denoted by the same reference numerals. The description is omitted.

  FIG. 12 is a block diagram showing a planar shape measuring apparatus according to Embodiment 3 of the present invention. The planar shape measuring apparatus 1 according to the third embodiment shown in FIG. 8 further includes a continuous imaging command device 20 in addition to the configuration of the first embodiment.

  Similarly to the first embodiment, the luminance level calculation device 18 calculates the luminance level of the width-direction image pickup device 7 while the plate presence / absence detection device 17 is in the plate presence detection state. The exposure time setting command device 6 has a plurality of values based on the brightness level calculated by the brightness level calculation device 18 and the exposure time table stored in the exposure time table storage device 5 before imaging by the planar shape imager 8. Are set to the continuous imaging command device 20.

  The exposure time setting command device 6 sets a plurality of different exposure times as follows, for example. The exposure time setting command device 6 estimates the surface temperature of the flat plate 100 from the brightness level calculated by the brightness level calculation device 18, refers to the exposure time table, and determines the exposure time suitable for the estimated surface temperature and the estimated surface temperature. An exposure time suitable for a high temperature or a temperature lower than the estimated surface temperature is set. For example, when three different exposure times are set, an exposure time suitable for the estimated surface temperature, an exposure time suitable for (estimated surface temperature + 25 ° C.), and an exposure time suitable for (estimated surface temperature + 50 ° C.) Set. Alternatively, an exposure time suitable for the estimated surface temperature, an exposure time suitable for (estimated surface temperature + 25 ° C.), and an exposure time suitable for (estimated surface temperature−25 ° C.) are set.

  The continuous imaging command device 20 instructs the planar image pickup device 8 to continuously capture images a plurality of times. When the continuous imaging command device 20 instructs the planar image pickup device 8 to perform imaging each time, the continuous imaging command device 20 instructs different exposure times each time based on a plurality of different exposure time setting values commanded from the exposure time setting command device 6. . The planar shape imager 8 collects a plurality of captured images 100d, 100e, 100f,..., 100n having different exposure times in response to a command to continuously capture images a plurality of times.

  The width edge coordinate arithmetic unit 9a performs image processing on a plurality of captured images captured by the planar shape image pickup device 8, detects an edge of the flat plate 100 for each captured image, and determines edge coordinates for measuring the width of the flat plate 100. Calculate. The length edge coordinate calculation device 9b performs image processing on a plurality of captured images captured by the planar image pickup device 8, detects an edge of the flat plate 100 for each captured image, and an edge for measuring the length of the flat plate 100 Calculate coordinates.

  The inter-edge coordinate width calculation device 10a calculates the interval between the rising edge coordinate and the falling edge coordinate for each of a plurality of captured images captured by the planar image pickup device 8 based on the calculation result of the width edge coordinate calculation device 9a. Thus, the width of the flat plate 100 is calculated. The edge coordinate width calculation device 10a may use an average value of calculation results for each of the plurality of captured images as a final calculation result. Alternatively, the edge coordinate width calculation device 10a may use the most accurate calculation result among the calculation results for each of the plurality of captured images as the final calculation result.

  Here, the most accurate calculation result is, for example, the following calculation result. For example, the calculation result is approximated by an Nth-order curve by a method such as a least square method. Data that deviates significantly from the approximate curve is considered noise. The calculation result with the smallest percentage of data that causes noise is considered to be the most accurate calculation result. Therefore, the calculation result with the smallest ratio of data greatly deviating from the approximate curve can be obtained as the most accurate calculation result.

  The inter-edge-coordinate length computing device 10b sets the interval between the rising edge coordinate and the falling edge coordinate for each of a plurality of captured images captured by the planar shape imager 8 based on the computation result of the length edge coordinate computing device 9b. By calculating, the length of the flat plate 100 is calculated. In the same manner as described above, the inter-edge coordinate length calculation device 10b finally calculates the average value of the calculation results for each of the plurality of captured images or the most accurate calculation result among the calculation results for each of the plurality of captured images. It is good also as a calculation result.

  The width edge center coordinate calculation device 11 a calculates the median value of the rising edge coordinate and the falling edge coordinate along the length direction of the flat plate 100 based on the calculation result of the width edge coordinate calculation device 9 a. In the same manner as described above, the width edge center coordinate calculation device 11a calculates the average value of the calculation results for each of the plurality of captured images or the most accurate calculation result among the calculation results of the plurality of captured images as the final calculation. As a result.

  The length edge center coordinate calculation device 11 b calculates the median value of the rising edge coordinate and the falling edge coordinate along the width direction of the flat plate 100 based on the calculation result of the length edge coordinate calculation device 9 b. In the same manner as described above, the length edge center coordinate calculation device 11b finally calculates the average value of the calculation results for each of the plurality of captured images or the most accurate calculation result among the calculation results for each of the plurality of captured images. It is good also as a calculation result.

  The tilt angle calculation device 12 calculates the tilt angle of the flat plate 100 with respect to the transport direction based on the calculation results of the width edge central coordinate calculation device 11a and the length edge central coordinate calculation device 11b. In the same manner as described above, the inclination angle calculation device 12 uses the average value of the calculation results for each of the plurality of captured images or the most accurate calculation result among the calculation results for each of the plurality of captured images as the final calculation result. Also good.

  The width profile calculation device 13 calculates the width profile of the flat plate 100 by correcting the verification result of the edge coordinate width calculation device 10 a based on the calculation result of the tilt angle calculation device 12. In the same manner as described above, the width profile calculation device 13 uses the average value of the calculation results for each of the plurality of captured images or the most accurate calculation result among the calculation results of the plurality of captured images as the final calculation result. Also good.

  The length profile calculation device 15 calculates the length profile of the flat plate 100 by correcting the verification result of the inter-edge coordinate length calculation device 10b based on the calculation result of the tilt angle calculation device 12. In the same manner as described above, the length profile calculation device 15 calculates the average value of the calculation results for each of the plurality of captured images or the most accurate calculation result among the calculation results of the plurality of captured images as the final calculation result. It is also good.

  The length direction bending shape calculation device 14 calculates the length direction bending shape of the flat plate 100 by correcting the verification result of the width edge central coordinate calculation device 11a based on the calculation result of the inclination angle calculation device 12. In the same manner as described above, the lengthwise bent shape calculation device 14 finally calculates the average value of the calculation results for each of the plurality of captured images or the most accurate calculation result among the calculation results for each of the plurality of captured images. It is good also as a calculation result.

  The width direction bending shape calculation device 16 calculates the width direction bending shape of the flat plate 100 by correcting the verification result of the length edge central coordinate calculation device 11b based on the calculation result of the inclination angle calculation device 12. In the same manner as described above, the width-direction bent shape calculation device 16 calculates the average value of the calculation results for each of the plurality of captured images or the most accurate calculation result among the calculation results for each of the plurality of captured images. As a result.

  In the third embodiment, a continuous imaging command device 20 is provided, and the planar shape imager 8 receives a plurality of different exposure time commands and collects a plurality of captured images with different exposure times. The calculation result is more stable by using the average value of the calculation results obtained from multiple images taken consecutively at different exposure times or the most accurate calculation result as the calculation result of each calculation device. A more accurate calculation result can be obtained.

  As described above, after the surface temperature of the flat plate 100 is temporarily lowered by contact with a roll of a rolling mill, water cooling, or the like, the surface temperature of the flat plate 100 is again reduced due to the recuperation effect due to heat conduction from the inside of the flat plate 100. May rise. For this reason, the surface temperature of the flat plate 100 may change from moment to moment. Even in such a case, according to the third embodiment, it is possible to select a captured image with appropriate brightness that is neither too bright nor too dark, so that more accurate edge coordinates are obtained and higher accuracy is obtained. An operation result is obtained.

  FIG. 13 is a diagram for explaining an operation at the time of imaging according to the third embodiment. With reference to FIG. 13, an operation when the width direction image pickup device 7 and the flat shape image pickup device 8 of the flat shape measuring apparatus 1 of the third embodiment image the flat plate 100 will be described.

  In FIG. 13, when the flat plate 100 is in the measurement range 28 of the planar image pickup device 8 and the position 100a on the upstream side of the visual field 27 of the width direction image pickup device 7 in the transport direction, a measurement start command is transmitted from an external device. When the measurement start command receiving device 3 receives a measurement start command from the outside, the command is sent to the measurement start timing generating device 4. In response to the measurement start command, the measurement start timing generator 4 issues a measurement command to the width direction image pickup device 7. In response to the measurement command, the width direction image pickup device 7 starts imaging.

  The transported flat plate 100 eventually enters the measurement range 28. When the flat plate 100 is at a position 100 b in the middle of entering the measurement range 28, the plate presence / absence detection device 17 outputs a plate presence signal based on the imaging signal of the width direction imaging device 7.

  The transported flat plate 100 eventually completely enters the measurement range 28. When the signal output from the plate presence / absence detection device 17 changes from a plate presence signal detecting the flat plate 100 to a plate no signal not detecting the flat plate 100, the measurement start timing generating device 4 detects the continuous imaging command device 20. To start measurement. The continuous imaging command device 20 commands the planar image pickup device 8 with a plurality of different exposure time setting values received from the exposure time setting command device 6. The planar shape imager 8 collects a plurality of captured images 100d, 100e, 100f,..., 100n by continuously capturing images a plurality of times while the flat plate 100 moves within the measurement range 28. The plurality of captured images 100d, 100e, 100f,..., 100n are captured at different exposure times set by the exposure time setting command device 6. FIG. 13 shows an example in which three captured images 100d, 100e, and 100f are captured. The number of times of imaging (the number of captured images) of the planar image pickup device 8 is not limited to three, and may be two or four or more.

  Next, an example of the operation flow of the planar shape measuring apparatus 1 according to the third embodiment will be described with reference to the flowchart shown in FIG. 14, but the difference from the operation flow according to the first embodiment (FIG. 4) will be mainly described. The description of the same points is omitted. The operation flow of the third embodiment is the same as the operation flow of the first embodiment except that steps S140 and S141 are provided instead of steps S109 and S110 of the operation flow of the first embodiment (FIG. 4). It is. As shown in FIG. 14, the operation flow of the third embodiment includes steps executed in the order of step S107, step S108, step S140, step S141, and step S111.

Step S107: The luminance level calculation device 18 samples the luminance level of the imaging signal of the width direction image pickup device 7 and calculates the luminance level.
Step S108: When the entire flat plate 100 enters the field of view (measurement range 28) of the planar image pickup device 8, the plate presence / absence detection device 17 detects the absence of the plate from the image pickup signal of the width direction image pickup device 7.

Step S140: The exposure time setting command device 6 sets a plurality of different exposure times with reference to the exposure time table on the basis of the calculation result of the brightness level calculation device 18, and instructs the continuous imaging command device 20 about these set values. To do.
Step S141: When the plate presence / absence detection device 17 detects the absence of a plate, the measurement start timing generation device 4 issues a measurement start command. The measurement start command is transmitted to the planar image pickup device 8 via the continuous imaging command device 20. The planar shape imager 8 continuously captures images a plurality of times based on a command from the continuous imaging command device 20. The planar shape imager 8 captures images with different exposure times each time based on a command from the continuous imaging command device 20. Thereby, the planar shape imager 8 collects a plurality of captured images 100d, 100e, 100f,..., 100n having different exposure times.

  Step S111: The width edge coordinate calculation device 9a performs image processing on a plurality of captured images captured by the planar image pickup device 8, detects the edge of the flat plate 100 for each captured image, and measures the width of the flat plate 100. Calculate edge coordinates. The length edge coordinate calculation device 9b performs image processing on a plurality of captured images captured by the planar image pickup device 8, detects an edge of the flat plate 100 for each captured image, and an edge for measuring the length of the flat plate 100 Calculate coordinates.

  In step S112 and subsequent steps, each arithmetic device calculates for each of the plurality of captured images, and calculates the average value of the calculation results for each of the plurality of captured images or the most accurate calculation result among the calculation results of each of the plurality of captured images. The final calculation result may be used. Alternatively, in step S111, the width edge coordinate calculation device 9a and the length edge coordinate calculation device 9b select the most accurate edge coordinate calculation result from among the edge coordinate calculation results for each of the plurality of captured images, and step S112 and subsequent steps. Then, each calculation device may perform calculation using the selected result of the most accurate edge coordinates.

  In the third embodiment, the exposure time setting command device 6 and the continuous imaging command device 20 set parameters for determining the light receiving characteristics of the planar shape imager 8 to a plurality of different values, and the parameters having the plurality of different values are set. It has a function as a parameter setting command device that commands the planar image pickup device 8 to sequentially and continuously image the flat plate 100 a plurality of times.

  As mentioned above, although embodiment of this invention was described, in this invention, you may implement combining several embodiment mentioned above arbitrarily.

DESCRIPTION OF SYMBOLS 1 Planar shape measuring device, 2 Flat plate temperature information receiving device, 3 Measurement start command receiving device, 4 Measurement start timing generating device, 5 Exposure time table storage device, 6 Exposure time setting command device, 7 Width direction imaging device, 8 Planar shape Imager, 9a Width edge coordinate computing device, 9b Length edge coordinate computing device, 10a Edge coordinate width computing device, 10b Edge coordinate length computing device, 11a Width edge central coordinate computing device, 11b Length edge center coordinate computing Device, 12 tilt angle calculation device, 13 width profile calculation device, 14 length direction bending shape calculation device, 15 length profile calculation device, 16 width direction bending shape calculation device, 17 plate presence / absence detection device, 18 brightness level calculation device, 19 peak hold processing device, 20 continuous imaging command device, 27 field of view, 28 measurement range, 100 flat plate, 100a, 100b position, 100d, 100e, 100f, 100n

Claims (5)

A two-dimensional camera for imaging a flat plate conveyed on a rolling line;
A temperature information detection device for detecting temperature information of the flat plate;
A storage device that stores a correspondence relationship between a parameter for determining a light receiving characteristic of the two-dimensional camera and a temperature of the flat plate;
A parameter setting command device for determining the setting of the parameter based on the temperature information detected by the temperature information detection device and the correspondence, and for commanding the determined setting of the parameter to the two-dimensional camera; ,
A profile value computing device that computes a profile value that identifies the planar shape of the flat plate from imaging data by the two-dimensional camera;
In the flat surface shape measuring apparatus Ru provided with,
A receiving device for receiving temperature information of the flat plate;
The parameter setting command device determines the parameter setting based on the temperature information received by the receiving device, the temperature information detected by the temperature information detecting device, and the correspondence relationship, and the determined parameter A planar shape measuring apparatus characterized by instructing the setting to the two-dimensional camera. A two-dimensional camera for imaging a flat plate conveyed on a rolling line;
A temperature information detection device for detecting temperature information of the flat plate;
A storage device that stores a correspondence relationship between a parameter for determining a light receiving characteristic of the two-dimensional camera and a temperature of the flat plate;
A parameter setting command device for determining the setting of the parameter based on the temperature information detected by the temperature information detection device and the correspondence, and for commanding the determined setting of the parameter to the two-dimensional camera; ,
A profile value computing device that computes a profile value that identifies the planar shape of the flat plate from imaging data by the two-dimensional camera;
In the flat surface shape measuring apparatus Ru provided with,
The temperature information detecting device is:
A one-dimensional camera having a linear field of view perpendicular to the transport direction of the flat plate;
A luminance level calculation device that calculates the luminance level of the image captured by the flat plate from the image data of the flat plate imaged by the one-dimensional camera;
Including
The visual field of the one-dimensional camera and the visual field of the two-dimensional camera are adjacent to each other,
Based on the imaging data of the one-dimensional camera, a plate presence / absence detecting device that detects that the flat plate has entered the visual field of the two-dimensional camera,
An imaging command device that commands the two-dimensional camera to take an image when it is detected by the plate presence / absence detection device that the flat plate has entered the field of view of the two-dimensional camera;
The planar shape measuring apparatus further comprising:   The temperature information detection device detects temperature information at a plurality of locations on the flat plate, and holds information on the highest temperature among the detected temperature information. Planar shape measuring device. The parameter setting command device commands the two-dimensional camera to set the parameter to a plurality of different values and sequentially capture the flat plate a plurality of times using the parameters of the plurality of different values sequentially. The planar shape measuring device according to any one of claims 1 to 3 , wherein Planar shape measuring apparatus according to any one of claims 1 to 4, characterized in that it comprises a distortion computation device for computing data related to distortion of the planar shape of the plate from the image data by the two-dimensional camera.

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