JP2000266516A - Device for detecting un-hot-scarfed length of end section of slab - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the automatic detecting accuracy of the un-hot-scarfed length of the end section of a slab after hot scarfing work completes with a hot scarfer. SOLUTION: A device for detecting un-hot-scarfed length is provided with an illuminator 5a which obliquely projects illuminating light upon a slab 1 transported in the (y) direction toward the upstream side of the slab 1 from the downstream side; a linear or slit-like line camera 6a which obliquely picks up the image of the illuminated surface of the slab 1 toward the downstream side from the upstream side and the visual field of which is extended in the width direction (x) of the slab 1; a picture processor 8a which writes the picture data of the camera 6a in a memory before the front end of the slab 1 enters the visual field of the camera 6a, displays a picture data group containing two-dimensionally distributed backgrounds not containing the front end of the slab 1 and slab images containing the front end and hot-scarfed area of the slab 1 on a CRT 10a after storing the picture data group, and calculates the un-hot-scarfed length Ly of the front end of the slab 1 by detecting the position y1 of the front end (y) of the slab 1 showing first luminance variation and the position y2 of a hot-scarfing starting point by showing second luminance variation based on the picture data group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the detection of an uncut area of a slab having a part of its surface cut, and particularly, but not exclusively, to a hot scuffer in a longitudinal direction y.
The present invention relates to the detection of the uncut length of the slab tip portion from the tip to the starting point of the slab.

[0002]

2. Description of the Related Art An uncut area at the tip of a slab is ground by a hot grinder in a lower step of a cutting and caring process using, for example, a hot scarer. The grinder performs automatic grinding while reciprocatingly driving the rotary grindstone in the slab width direction x. This type of grinding method and grinding machine is disclosed in Japanese Patent Application Laid-Open No. 4-28306.
No. 5 and JP-A-57-41157.

[0003]

If the actual distance from the tip of the slab to the start of cutting in the longitudinal direction, that is, the uncut length, is not given, the grinding length (y direction) of the automatic grinding machine is the operating length.
Data is set. If the set value is short, grinding leakage will occur.
A sufficient length is set. Therefore, the number of reciprocations of the rotating grindstone is relatively large, and it takes time for automatic grinding. Therefore,
It is preferable to automatically detect the uncut length (y direction) from the slab tip to the starting point of the slab remaining in the cutting by the hot scuffer in the previous step and to give the same to the automatic grinding machine as the grinding target length.

A first object of the present invention is to automatically detect the distance from the tip of the slab to the starting point of cutting, ie, the uncut length, and to improve the detection accuracy.

[0005]

(1) The apparatus for detecting the uncut length at the end of a slab according to the present invention is a slab conveyed in the y direction.
(1), illuminating means (5a) for projecting illumination light obliquely from the downstream side to the upstream side in the transport direction; the slab surface on which the illumination means (5a) has projected light is moved upstream in the transport direction. A linear or slit line camera (6a) whose field of view extends obliquely in the slab width direction x from the side to the downstream side; a line camera before the slab tip enters the field of view of the line camera (6a) The image data of (6a) is written into a memory, and in the memory, a group of image data of a two-dimensionally distributed background having no slab tip and a slab image including the slab tip and the ablated area is stored. Image reading means (8a); and, based on the image data group, y of the first luminance change from the low luminance background to the tip of the slab which is an uncut portion having higher luminance than the background.
The position (y1) and the y-position (y2) of the second luminance change from the uncut portion to the lower-intensity cutting start point are detected, and both positions (y
1, y2) (Ly = y2-y1) as the uncut length.

[0006] In order to facilitate understanding, the reference numerals of the corresponding elements in the embodiments shown in the drawings and described later are added in parentheses for reference.

Since the illuminating means (5a) irradiates the slab (1) with illumination light obliquely from the downstream side to the upstream side in the conveying direction y, the boundary between the uncut portion and the cut portion of the slab is provided. There is a dark shadow in the deep part. Since the line camera (6a) obliquely shoots the illuminating portion on the slab surface from the upstream side to the downstream side in the transport direction y, the camera (6a) operates when the slab tip enters the camera field of view. (x, z plane) is not photographed, and the slab tip appears in the photographed image as a clear edge of high luminance against a low luminance background without light reflection, and the edge can be grasped accurately. Since the field of view of the line camera (6a) is linear or slit extending in the slab width direction x, the deep portion of the boundary between the uncut portion and the cut portion of the slab is:
In the photographed image, a clear shadow having a lower luminance than that of the uncut portion at the tip of the slab appears, and the starting point of the cut can be accurately grasped.

On the basis of such a photographed image, the luminance change detecting means (8a) detects the y position (y1) of the first luminance change from the low luminance background to the slab tip which is an uncut portion having a higher luminance than the background. )
And the y position (y2) of the second luminance change from the uncut portion to the cutting start point portion having a lower brightness than that, and the difference (Ly = y2-y1) between the two positions (y1, y2) is detected. Is calculated as the uncut length, an accurate uncut length can be obtained. By giving this uncut length as the target grinding length to the automatic grinding machine in the downstream process, the automatic grinding machine grinds only the required length. Grinding work efficiency is improved.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (2) Slab detecting means (4) for detecting the arrival of a slab (1); and starting the measurement of the slab conveyance distance from the detection of the arrival of the slab, the measured value is determined by the slab tip. A measurement control unit (12) for giving a measurement command to the image reading unit (8a) when the value (La) becomes a value that is a set distance before the field of view of the line camera (6a); In response to the measurement command, the reading means (8a) stores digitally converted data, i.e., image data, of a video signal generated by the line camera (6a) for each set line at a predetermined pitch in line units. To detect the uncut length at the end of the slab.

According to this, the image data group including the front end of the slab and the background in front of the slab is automatically written into the memory substantially without the intervention of the operator. (3) The brightness change detecting means (8a) determines a window area for designating a partial area of an image on a two-dimensional plane represented by the image data group in the memory, and determines image data belonging to the window area. Based on the group, y of the first luminance change from the low-luminance background to the slab tip, which is an uncut portion with higher luminance than the background,
The position (y1) and the y-position (y2) of the second luminance change from the uncut portion to the lower-intensity cutting start point are detected, and both positions (y
An apparatus for detecting the uncut length at the end of the slab, which calculates the difference (Ly = y2-y1) of (1, y2) as the uncut length.

According to this, the amount of image data to be processed for obtaining the uncut length is small, the image processing is easy, and the time required for calculating the uncut length is short. (3) The image reading means (8a) displays an image represented by the read image data group on a two-dimensional display (10a), and the luminance change detecting means (8a) displays an index representing the window area. A device for detecting an uncut length of an end of a slab, which is displayed at a position corresponding to the image on the two-dimensional display (10a).

Since the window index appears on the photographed image, the operator can easily recognize the relative position and size of the window area with respect to the slab image. If the luminance change detecting means (8a) changes the window position and the size in accordance with the operator's input, the operator can:
A small-sized window with high uncut length calculation efficiency can be easily set at a position where high accuracy of the uncut length calculation is expected. (4) The image reading means (8a) displays an image represented by the read image data group on a two-dimensional display (10a), and the luminance change detecting means (8a) performs first and second luminance change. A mark indicating the y position (y1, y2) of the slab end at the corresponding position of the image on the two-dimensional display (10a).

A sign indicating the slab start position (y1) and a sign indicating the cutting start position (y2) appear on the photographed image.
The operator can visually determine whether or not the processing of the luminance change detecting means (8a) is normal, and whether or not the uncut portion has been detected is correct and its accuracy.

Other objects and features of the present invention will become apparent from the following description of embodiments with reference to the drawings.

[0015]

FIG. 1 shows an outline of an embodiment of the present invention. The upper and lower surfaces of the slab 1 are moved from a position of several cm or several tens cm from the tip (left end) to the tail end (right end) by a hot scuffer (not shown) in the upper step (right direction in FIG. 1). It is then cut by a transport table and sent to a hot grinder (not shown) in a lower step (to the left in FIG. 1). Below the transport table are an illuminator 5a and a line camera 6a for photographing the lower surface of the slab 1,
Above the transport table, there are an illuminator 5b and a line camera 6b for photographing the upper surface of the slab 1.

The illuminator 5a is arranged so that a dark shadow appears at the boundary between the uncut portion and the cut portion at the tip of the slab 1 so that each roller in the row of rollers of the transport table can be seen. The transfer direction y with respect to the transfer surface (x, y plane) including the slab support point of
The illumination light is projected obliquely from the downstream side to the upstream side.
The line camera 6a has a linear or slit-shaped field of view extending in the slab width direction x, and photographs the transport surface illuminated by the illuminator 5a obliquely from the upstream side to the downstream side in the transport direction y. When the tip of the slab 1 is located on the upstream side of the visual field of the line camera 6a, the light of the illuminator 5a travels obliquely upward and does not enter the visual field of the camera 6a. Is extremely low.

When the tip of the slab 1 enters the field of view of the line camera 6a, part of the light reflected by the field of view of the line camera 6a on the slab 1 is directed to the line camera 6a, and the image signal level of the line camera 6a (Brightness) increases, but is relatively low because the tip is uncut. When the tip of the slab 1 passes through the camera field of view and the start point of the deep part at the boundary between the uncut portion and the cut portion reaches the camera field of view,
The reflected light toward the camera in the camera field of view on the slab 1 is drastically reduced, thereby lowering the image signal level of the camera 6a. While the deep downward slope passes through the camera field of view on the slab 1, the photographing signal level of the camera 6a remains low. Next, while the bottom of the deep depression is passing through the camera view area, the photographing signal level of the camera 6a rises and approaches the photographing signal level on the fusing plane (high reflection surface). Next, while the upwardly inclined surface of the deep depression passes through the camera viewing area, the illumination light is reflected toward the illuminator 5a, so that
The photographing signal level of the camera 6a decreases. Then, when the substantially flat steady-cut surface enters the visual field of the camera, the photographing signal level becomes extremely high.

FIG. 4 shows a slab photographed image obtained by continuously photographing a line (slit) from a point just before the tip of the slab 1 enters the visual field of the camera to a considerable portion of the steady cutting surface and forming a two-dimensional image. The outline of the change of the photographing signal level (luminance) described above is shown on the left side of step 38 in FIG.

The linear camera 6a repeatedly shoots at a fixed period, and repeatedly outputs a line (or slit) image signal at the fixed period. Each time the rotary encoder 3 generates a pulse, the image processing device 8a converts the immediately following one-line image signal into digital data in pixel units, and converts digital data (image data) therein. An original image memory (hereinafter referred to as a primary memory) is written, and an image data group representing a two-dimensional screen shown in FIG. 4 is collected on the primary memory. In order to simplify the illustration, the image shown in FIG. 4 is shown by extracting a part of the width in the x direction of a wide two-dimensional screen representing the entire image data group on the primary memory. Things. The field of view of the camera 6a in the x-direction on the transport surface is 1800 mm. When a slab having an x width smaller than 1800 mm is photographed as usual, a wide two-dimensional screen representing the entire image data group on the primary memory is obtained. Indicates the entire width of the slab in the x direction.

The distributor 9a transmits data output from the image processing device 8a to a CRT (two-dimensional cathode ray tube display) 1.
0a or the laser printer 11a. The measurement controller 12 designates which one to give.

The above-described illuminator 5a to laser printer 11a
Another set 5b to 11b having substantially the same configuration as the set
Are provided for photographing the upper surface of the slab 1. The second set of illuminators 5b and line cameras 6b are symmetric with respect to the y-axis with the first set of illuminators 5a and line cameras 6a,
Irrespective of the presence or absence of the slab 1, y such that the light emitted from the first set of illuminators 5a does not enter the camera 6b, and the light emitted from the second set of illuminators 5b does not enter the camera 6a.
The position is shifted in the direction.

A rotary encoder 3 is connected to one of the rollers 2 of the transport table, and is rotated by a predetermined small angle (movement of the slab 1 over a predetermined short distance) by one. A pulse electric signal is generated and supplied to the measurement controller 12.
A slab sensor 4, which is a reflection-type optical sensor, is provided slightly downstream of the roller 2, and a signal indicating whether or not a slab exists immediately below the slab sensor 4 is given to a measurement controller 12.

The image processing devices 8a and 8b and the measurement controller 12 are provided with an input / output board, and an operator can input data and commands.

FIG. 2 shows “measurement” of the measurement controller 12.
An outline of the control will be described. When the measurement mode is designated and execution is instructed, the measurement controller 12 performs the "measurement" control shown in FIG. 2 until an end or stop is input. In the input reading (step 1), the input from the input / output board and the input from the image processing devices 8a and 8b are read. In the following, the word “step” is omitted in parentheses, and step No. Write only numbers.

When an input from the input / output board, that is, an operator input is read in the input reading (1), the measurement controller 12 performs data processing and setting corresponding to the input. This includes the setting of the position and size of the measurement window according to the operator input. When the data transfer ready from the image processing devices 8a and 8b is read in the input reading (1), the data is read from the image processing devices 8a and 8b and the CRTs 10a and 1 are read.
0b is included. When there is no input,
Perform step 6 and subsequent steps.

That is, it waits for the electric signal of the slab sensor 4 to switch from the absence of the slab to the presence of the slab (6-7-).
(1-6-7...), And when it is switched to the presence of a slab, 1 indicating that a slab is being detected is written to the register SDF (one area of the internal memory of the measurement controller 12) (6).
-8-9), Slab No. Register SNo. Is updated to a value indicating one greater value (10), and counting of the pulse generated by the rotary encoder 3 is started. That is, the measurement of the movement amount of the slab 1 is started (1
1).

Next, the pulse count value (the amount of slab movement)
Waits for the first set value Lb (the value at which the tip of the slab is located a predetermined value upstream of the field of view of the camera 6b), and then, gives a measurement command to the image processing device 8b, and sets the camera 1 indicating that the shooting by 6b has started is written (13-16).

Next, when the pulse count value is equal to the second set value L
a (a value at which the tip of the slab is located a predetermined value upstream of the field of view of the camera 6a), and then, a measurement command is given to the image processing device 8a, and photographing by the camera 6a is started to the register AF. Is written (1
7-20).

In response to the measurement command, the image processing devices 8b and 8a start reading the photographing signal, and when reading of one two-dimensional screen is completed, start the image data processing and start the uncut length. The calculation of Ly is performed. This content will be described later with reference to FIG.

Thereafter, the measurement controller 12 waits for the electric signal of the slab sensor 4 to switch from the presence of the slab to the absence of the slab (6 to 8-13-17-1 to 8-13...).
), When switching without slab, register SD
F, BF, and AF are cleared (22 to 24), and the process waits until the tip of the next slab reaches directly below the slab sensor 4 (1).
-7-1 to 7 -... repeated). "Input reading"
In (1), an operator input or an image processing device 8b, 8
When the input from a is read, the processing corresponding to the input (3,
Perform 5).

FIG. 3 shows the contents of "measurement of uncut length" of the image processing device 8a. When the uncut length measurement mode is designated and execution is instructed, the image processing device 8a performs "uncut length measurement" shown in FIG. 3 until an end or stop is input. First, it waits for a measurement command from the measurement controller 12 (31). When a measurement command is given, the image processing device 8a instructs the video controller 7a to output an image signal, and outputs a line image signal repeatedly output by the video controller 7a at regular intervals in image data in units of pixels. (Digital data) and writes it to the primary memory. In this embodiment, A / D conversion is performed on image data of 256 gradations where the minimum luminance level of the line image signal is 0 and the maximum luminance level is 255.

The image processing device 8a counts the number of written lines, and when the count value reaches a set value, notifies the measurement controller 12 of the image data ready, and the measurement controller 12 sends the image data ready to the CRT 10a. Data transfer is instructed, and the image processing device 8a transfers the image data of the primary memory to the CRT 10
Output to a (32). At this time, the image processing device 8a
The index image representing the measurement window position and size is transferred while being superimposed on the image data (33). This gives C
An image before and after the slab tip and a measurement window (for example, FIG. 4) are displayed on the RT 10a. Here, the operator can operate the input / output board of the image processing device 8a to adjust the position and size of the measurement window.

Next, the image processing device 8a checks the image data of the wide area including the window area and the area of the width of 32 pixels in the x direction outside the two sides parallel to the y direction.
If it indicates a value of 0 or less, it is rewritten to data representing 0 (lowest luminance), and if it indicates a value of 21 or more, it is written to the secondary memory as it is (34). Next, for each of the pixels in the window area, the average value of the image data of the 64 pixels in the x direction centered on the pixel of interest (the pixel of interest) is calculated, and the average value of the image data of the pixel of interest is shown. To be rewritten. Then, the processing target image data on the secondary memory is defined only in the window area (35). Next, the image processing device 8a searches for the peak value of the image data in the window area on the secondary memory, and finds the line (y) where the peak value (reflection luminance of the high-luminance welding surface) exists. ) Of the image data in the window area on the secondary memory, and calculates an average value of the image data of the window area on the secondary memory. Rewrite all data to data representing 255 (highest luminance) (36).

Next, the image processing device 8a calculates the sum (integrated value) of the image data in the window area on the secondary memory at the same y position, and sends a table (internal) to the y position. (One area of the memory) (37). Then, for each of the y positions, y with its (target position) as the center
The average of the integrated values at the three positions in the direction is calculated, and the integrated value at the target position on the table is rewritten to the average (38). When the integrated value of each y position obtained by this is displayed in a graph,
A graph as shown on the left side of step 38 in FIG. 3 is obtained.

Next, the image processing unit 8a calculates the derivative value of the integrated value (average value) on the table in the y direction (the integrated value of the adjacent y position at the upstream position in the y direction−the integrated value of the downstream position: positive). Is the luminance rise, negative is the luminance fall), and the differential value is checked from the most downstream (slab tip) side to the upstream (slab tail end) side. Is the y-position y1 of the peak value in the region where
The slab tip is determined, then the y-position y2 of the peak value in the region where the differential value becomes negative and its absolute value rises above the set value, that is, the second change point, starts the cutting on the slab. The point is determined, and the uncut length Ly = y2-y1 is calculated (39).
Then, the data ready is notified to the measurement controller 12. The measuring controller 12 responds to this by sending the uncut length L
y data is received from the image processing device 8a (40), and the slab No. Register SNo. The data is transferred to an automatic grinding machine (not shown) in the lower step.

Next, the image processing device 8a determines the position corresponding to the measurement window and the calculated values y1 and y2 on the slab image represented by the image data group in the primary memory.
The y1-corresponding position (the position recognized as the tip) and the y2-corresponding position (the position recognized as the cutting start point) on the slab image are calculated, and the standard image displayed at those positions and the display of the calculated uncut length Ly are displayed. The data is superimposed on the image data in the primary memory and output to the CRT 10a (41). This allows CT
As shown in FIG. 4, a slab tip marker and a fusing start marker are displayed on R10a in addition to the window frame. When the above processing is completed, the image processing device 8a waits for the next measurement command (31).

The above-described “measurement of uncut length” (FIG. 3)
Another set of image processing devices 8b executes the same processing as the above. Therefore, a lower surface image of the tip portion of the slab 1 is displayed on the CRT 10a, for example, as shown in FIG.
, A top image of the tip of the slab 1 is similarly displayed. The unmilled length Ly of the lower surface and the upper surface of the leading end of the slab 1 is given to an automatic grinding machine (not shown) in the lower step. The automatic grinding machine grinds the tip of the lower surface with the given uncut length of the lower surface as the target grinding length from the tip of the lower surface of the slab, and also gives the uncut length of the given upper surface to the upper surface of the slab. Then, the top end portion is ground as a target grinding length from the front end.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of an embodiment of the present invention, showing a side surface of a slab transfer line.

FIG. 2 is a flowchart showing the contents of "measurement" control of a measurement controller 12 shown in FIG.

FIG. 3 is a flowchart showing the contents of “measurement of uncut length” of the image processing apparatus 8a shown in FIG. 1;

FIG. 4 is a plan view showing a part of an image displayed on the CRT 10a shown in FIG.

[Explanation of symbols]

1: Slab 2: Roller 3: Rotary encoder 4: Slab sensor 5a, 5b: Illuminator 6a, 6b: Line camera

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Masato Sugiura 20-1 Shintomi, Futtsu City Nippon Steel Corporation Technology Development Division F-term (reference) 2F065 AA09 AA12 AA21 AA51 BB05 BB11 BB15 CC06 DD06 FF42 FF67 HH12 JJ02 JJ05 JJ08 JJ25 MM03 PP16 QQ03 QQ13 QQ24 QQ25 QQ27 QQ36 QQ42 QQ45 QQ51 SS02 SS06 SS13 TT07

Claims (5)

[Claims] An illumination means for projecting illumination light obliquely from a downstream side to an upstream side in a transport direction with respect to a slab transported in a y-direction;
Shoot diagonally from the upstream side to the downstream side in the transport direction,
A linear or slit line camera whose field of view extends in the slab width direction x; before the slab tip enters the field of view of the line camera, image data of the line camera is written to a memory, and a two-dimensional distribution of the data is stored in the memory. Image reading means for storing image data of a slab image including a slab tip and a slab image including a slab tip and an ablated region; and a low-brightness background based on the image data. The y position of the first luminance change to the slab tip, which is the unblown part having a higher luminance than the background, and the y position of the second luminance change from the non-blown part to the fusing start point having a lower luminance, And a brightness change detecting means for calculating a difference between the two positions as an uncut length, and a slab end uncut length detecting device. 2. Slab detecting means for detecting the arrival of a slab;
The slab conveyance distance measurement is started from the detection of the arrival of the slab, and when the measured value becomes a value that is a set distance before the slab tip from the visual field of the line camera, the measurement command is sent to the image reading unit. The image reading means responds to the measurement command and converts the video signal generated by the line camera into line units for a set line at a predetermined pitch, that is, image data. 2. The apparatus for detecting an uncut length at the end of a slab according to claim 1, wherein the data is written into the memory. 3. The brightness change detecting means determines a window area for designating a partial area of an image on a two-dimensional plane represented by the image data group in the memory, and the image data group belonging to the window area. From the low-luminance background, the y-position of the first luminance change from the low-luminance background to the slab tip, which is an uncut portion having a higher luminance than the background, The uncut length detection device at the end of the slab according to claim 1, wherein the y position of the second luminance change is detected, and the difference between the two positions is calculated as the uncut length. 4. The image reading means displays an image represented by the read image data group on a two-dimensional display, and the luminance change detecting means displays an index representing the window area.
The apparatus for detecting an uncut length of an end portion of a slab according to claim 3, wherein the apparatus displays the uncut length at a position corresponding to the image on the two-dimensional display. 5. The image reading means displays an image represented by the read image data group on a two-dimensional display, and the luminance change detecting means displays a sign indicating the y position of the first and second luminance changes. 5. The apparatus for detecting uncut length of an end of a slab according to claim 1, wherein said apparatus is displayed at a position corresponding to said image on said two-dimensional display.