JPH10318719A - Method and apparatus for detection of plate width and meandering - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a method and an apparatus in which the end part (the edge part) of even a nonradiant steel sheet belt can be detected with high accuracy and by a low-cost and extremely simple technique. SOLUTION: The position of incidence or the angle of incidence of optical fiber cables 30, 31 which transmit light to glass rods 34, 35 at illumination heads 32, 32 is adjusted. A grade is given to the intensity of irradiation light radiated from the illumination heads 32, 33. The distribution of the intensity of beams of reflected light from end parts 22, 23 of a rolled material 21 is made nearly uniform irrespective of distances from the illumination heads 32, 33. The plate width and the meandering amount of the rolled material 21 being rolled are detected. The detecting accuracy of the end parts 22, 23 of the rolled material 21 is enhanced sharply. The end parts 22, 23 can be detected with extremely high accuracy even with reference to the rolled material 21 which does not generate a radiation and whose temperature is low. As a result, the performance of hot rolling apparatus is enhanced remarkably.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for detecting the width and meandering of a steel sheet in a hot rolling facility.

[0002]

2. Description of the Related Art In hot rolling equipment, a technique for accurately detecting the width and meandering amount of strip steel is an indispensable technique for maintaining the performance of a hot rolling apparatus.

As shown in FIG. 6, a conventional apparatus for detecting the width and meandering of a strip steel photographes edges (ends) 2 and 3 in the strip width direction of a strip steel (rolled material) 1. End 2
Two cameras 4, 5 and 6,
7, the visible and infrared radiations from the hot rolled material 1 are detected by the cameras 4, 5 and the cameras 6, 7. Images captured by the cameras 4 and 5 and the cameras 6 and 7 are converted into analog image signals, and transmitted to the image signal input unit 13 via the cables 9 to 12.

The image signal input unit 13 converts the digital signal into a digital signal and stores the digital signal. From the stored image signal, the edge detection processing unit 14 performs image processing such as threshold processing of the image luminance, and performs processing of the rolled material 1. The positions of the ends 2 and 3 are detected. The meandering amount and the sheet width of the rolled material 1 are calculated by the meandering amount / sheet width calculating unit 15 from the determined end portions 2 and 3 of the rolled material 1 and the set positions of the cameras 4 and 5 and the cameras 6 and 7. And gives it to the monitor 16 as a detection amount.

[0005] The meandering amount D to be determined is the amount of deviation between the mechanical center 17 and the sheet width center 18 of the rolled material 1 in the sheet width direction. The meandering amount D and the plate width W are the setting conditions of the cameras 4, 5 and the cameras 6, 7, the positions and inclinations of the cameras 4, 5, and the cameras 6, 7, and the positions of the ends 2, 3 starting from the camera position. Straight line y1,
It can be calculated from y2, y3, y4.

[0006] The prior art described above includes a self-luminous system in which the target rolled material 1 is heated and detected by the cameras 4 and 5 and the cameras 6 and 7 to emit light that emits light in the visible and infrared regions. Light source 2 with fluorescent light 19 etc.
There is a backlight system in which 0 is arranged and a portion where the brightness changes at the boundary between the light source 20 and the rolled material 1 is detected as an end from an image passed through an optical filter for removing self-emission from the rolled material 1.

[0007]

However, in the self-luminous method, when the temperature of the rolled material 1 falls to 500 ° C. or less, the wavelength of the emitted radiation becomes long, and the detection of the cameras 4 and 5 and the cameras 6 and 7 is performed. Since the wavelengths fall outside the wavelength range, the detection of the end portions 2 and 3 by the cameras 4 and 5 and the cameras 6 and 7 becomes impossible. Further, in the backlight system, the light source 20 is a rolled material 1
Erroneous detection occurs due to a decrease in the amount of light due to the adhesion of water scale and dirt to the light source 20 and the adhesion of the scale of the rolled material 1, and frequent maintenance is required.

As described above, in the case of the rolled material 1 in which the temperature of the rolled material 1 is lowered and the wavelength of radiation in the visible and infrared regions is not within the detection wavelength range of the cameras 4 and 5 and the cameras 6 and 7, The detection accuracy of the ends 2 and 3 is significantly reduced. For this reason, it is conceivable to provide a separate light source and take measures to illuminate the rolled material 1 from above the rolled material 1 using an optical fiber cable or the like. Uniformity occurs, making it difficult to detect the ends 2 and 3 with high accuracy, which significantly affects the performance of the entire rolling mill.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and enables highly accurate detection of an end portion (edge portion) even for a strip steel that does not generate radiation by a low cost and extremely simple method. It is an object of the present invention to provide a method and an apparatus for detecting a plate width and meandering.

[0010]

According to the present invention, there is provided a strip width / meander detecting method for achieving the above object, wherein a strip width of the strip steel is determined from an imaging state obtained by illuminating the strip steel during rolling. What is claimed is: 1. A sheet width and meandering detection method for a steel sheet hot rolling facility for detecting a meandering amount, the method comprising: adjusting an incident position or an incident angle of an optical fiber cable for transmitting light to a glass rod portion of an illumination head; A gradient is given to the light intensity, and the intensity distribution of the reflected light from the edge of the strip steel is made substantially uniform regardless of the distance from the illumination head, and the strip width and meandering amount of the strip steel during rolling are detected. It is characterized by doing.

According to another aspect of the present invention, there is provided a strip width and meandering detecting apparatus for detecting a strip width and a meandering amount of a strip steel from an imaging state obtained by illuminating the strip steel during rolling. A strip width and meandering detection device in a hot rolling facility for a steel sheet, comprising: an illumination head including a lens and a glass rod; a lamp for supplying light to the illumination head; a light condensing device; and the glass rod. A light source composed of an optical fiber cable whose incident state can be adjusted, and the vicinity of both edges of the strip steel for imaging the edges of the strip steel by reflected light of light applied to the strip steel. An imaging device installed on the upper part with two pairs each being shifted in phase,
A signal processing device that performs arithmetic processing on a signal from the imaging device and a monitor unit, and adjusts an incident position or an incident angle of the optical fiber cable that transmits light to the glass rod unit, and irradiates light intensity emitted from the illumination head. And the intensity distribution of the reflected light from the edge of the strip steel is made substantially uniform regardless of the distance from the illumination head to detect the width and meandering amount of the strip steel during rolling. It is characterized by the following.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In illumination using an optical fiber cable, a transparent glass rod is disposed at the exit of the optical fiber cable in order to make the intensity distribution of the illumination uniform, and light is reflected by the reflection inside the glass rod. The intensity distribution is made substantially constant, and the light is condensed by a plurality of lenses and irradiated onto an object. Usually, the center of the glass rod and the center of the optical fiber cable are used in alignment.

However, in this method, the light intensity at the edge of the strip steel is strong when the strip steel is meandering and approaches the illumination head, becomes weaker when the strip steel is moved away, and is far and near due to the meandering in the width direction of the strip steel. In this case, it is difficult to measure when the light intensity is greatly changed and the light is separated. For this reason, it is difficult to accurately grasp the meandering amount.

The intensity distribution of the illumination light can be changed by shifting the center position of the optical fiber cable with respect to the glass rod so as to be eccentric, or by taking measures to incline the central axis of the glass rod and the optical fiber cable. Accordingly, a means is provided for eccentrically or inclining the relative position between the glass rod and the optical fiber cable so that the light intensity distribution at the edge is constant regardless of where the edge of the strip steel is located.

[0015]

FIG. 1 shows an overall configuration of a plate width / meandering detection device according to an embodiment of the present invention. FIG. 2 shows a light emission distribution of an illumination head.
FIG. 3 shows the intensity distribution of the reflected light, FIG. 4 shows the schematic configuration of the illumination head, and FIG. 5 shows the state of the optical path in the glass rod. In the present embodiment, the eccentricity of the central axis between the optical fiber cable and the glass rod makes the light intensity distribution on the strip steel constant, thereby improving the edge detection accuracy by the camera.

As shown in FIG. 1, for example, an edge portion (end portion) 2 of a strip steel (rolled material) 21 having a width of 2000 mm in the width direction of the plate.
The end portions 22, 23 are used in order to take a picture with the field of view 2, 23 in view.
, Two cameras 24 as imaging devices,
25 and cameras 26 and 27 (viewing angle 24 degrees). The cameras 24, 25 and the cameras 26, 27 are arranged such that the cameras 24, 26 on the machine center side have an angle θ ₁ (θ
₁ = 12 degrees) and located at a height of 950 mm from the plate surface, and the cameras 25 and 27 outside thereof are positioned at angles θ ₂ (θ ₂ = 2) only in the plate width direction.
(1 degree) at a height of 860 mm from the plate surface, and the inner cameras 24 and 26 and the outer cameras 25 and 27 each photograph the same portion of the rolled material 21 at an interval of 130 mm in the plate width direction.

From a metal halide lamp light source (light source) 28, 29 having an output of 60 watts, an optical fiber cable 3
At 0 and 31, light is guided to the illumination heads 32 and 33, and the light is irradiated to the camera shooting position of the rolled material 21. Lighting head 32,
The position 33 is located between the inner cameras 24 and 26 and the outer cameras 25 and 27 in the board width direction, is 960 mm in height, and has an angle of 16 degrees in the board width direction and 20 degrees in the line direction.

At this time, since the relative positions of the central axes between the optical fiber cables 30, 31 of the illumination heads 32, 33 and the glass rods 34, 35 are shifted and decentered, the light intensity at the exits of the illumination heads 32, 33 is increased. The distribution 36 is not constant, and the machine center side far from the rolled material 21 is bright. By irradiating the rolled material 21 with this light, the light intensity distribution 37 becomes constant on the rolled material 21, and the cameras 24 and 25 and the cameras 26 and 27 can detect the ends 22 and 23 of the rolled material 21. .

Image signals photographed by the cameras 24 and 25 and the cameras 26 and 27 are input to an image signal input section 45 via cables 41 to 44 and further to an edge detection processing section 46. Then, after being processed by the meandering amount / board width calculation processing section 47, it is displayed on the monitor section 48 and monitored.

As shown in FIG. 4A, the optical fiber cable 30 (31) is a bundle type having a diameter of 8 mm, and the glass rod 34 (35) in the illumination head 32 (33) has a width of 26 m.
m, height 8mm, length 79mm, lens 51 (52) has 5 aperture
Illumination is performed using three 0 mm focal lengths and 120 mm focal lengths.

In the illumination using the optical fiber cable 30 (31), a transparent glass rod 34 (35) is connected to the optical fiber cable 30 in order to make the illumination intensity distribution uniform.
It is arranged at the exit of (31) and makes the distribution of the light intensity substantially constant using the reflection inside the glass rod 34 (35).
The light is condensed by the lenses 51 (52) and irradiated onto the rolled material 21. Normally, as shown in FIG.
The center of (35) and the center of the optical fiber cable 30 (31) are used in alignment.

However, in this method, the end 2 of the rolled material 21
The light intensities 2 and 23 are strong when the rolled material 21 meanders and approaches the illumination head 32 (33), and becomes weaker when the rolled material 21 separates.
The light intensity changes greatly at a distance due to the meandering of the rolled material 21 in the width direction, and it is difficult to measure when the rolled material 21 is separated. For this reason, it is difficult to accurately grasp the meandering amount.

As shown in FIGS. 4B and 4C, the optical fiber cable 30 (3) is connected to the glass rod 34 (35).
The intensity distribution of the illumination light can be changed by shifting the center position of 1) to decenter, or by taking measures to incline the center axis of the glass rod 34 (35) and the optical fiber cable 30 (31). 4 (b) and FIG. 4 (c), the glass rod 34 (so that the light intensity distribution of the ends 22, 23 becomes constant no matter where the ends 22, 23 of the rolled material 21 are located. 35) and the optical fiber cable 30
Means for decentering or tilting the relative position of (31) is taken.

FIG. 2 shows the light intensity distribution of the illumination head 32 described above.
Shown in The light intensity distribution shown in FIG. 2 is obtained by placing a translucent screen at a position 1 m in front of the illumination head 32, taking an image with a camera from the opposite side of the screen from the illumination head 32, and examining the light intensity I and the width of the glass rod. It shows the relationship between the direction and the position in the height direction.

FIG. 2 (a) shows a case where the optical fiber cable 30 is illuminated at the center of the glass rod 34 without tilt, and the surface of the rolled material 21 perpendicular to the optical axis in the width direction Smm of the glass rod 34 is shown. (Approximately 460 mm), and a range in the height direction Rmm (approximately 140 mm) of the glass rod 34 is almost uniformly illuminated.

FIG. 2 (b) shows a case where the optical fiber cable 30 is eccentric in the width direction by 4 mm from the center of the glass rod 34 (see FIG. 4 (b)). Illumination makes it possible to provide a brightness difference of about twice on the left and right in the width direction of the glass rod 34.

FIG. 2C shows that the optical fiber cable 30 is located at the center of the glass rod 34, and one of the ends of the optical fiber cable 30 in the width direction is L shown in FIG.
2 (b), and it is possible to make a difference in brightness in the width direction similarly to FIG. 2 (b).

The relative positional relationship between the optical fiber cables 31 and 32 and the glass rods 34 and 35 is defined by the center axes of the optical fiber cables 31 and 32 and the glass rods 34 and 35.
By eccentricizing the central axis of, or by providing an inclination between the central axes, the intensity distribution of the illumination light irradiated onto the rolled material 21 becomes constant. How the eccentricity of the central axes and the inclination between the central axes act on the optical paths in the glass rods 34 and 35 will be described with reference to FIG.

FIG. 5A shows a conventional arrangement, in which the centers of the optical fiber cables 31 and 32 and the glass rods 34 and 35 coincide with each other. Glass rods 34, 35
The light path inside is symmetrical about the central axis,
The distribution of the light intensity exiting 4,35 is constant. When this light is illuminated obliquely onto the rolled material 21 as illumination, the light intensity at the exits of the glass rods 34 and 35 is uniform as shown in the middle diagram of FIG. Are the glass rods 34 and 35 as shown in the left diagram of FIG.
It is strong when the distance x from is short, and weak when the distance x is large.

When the eccentric type is adopted as shown in FIG. 5 (b), the reflected light in the glass rods 34, 35 is deflected to one side (downward in the figure), and the light intensity at the exits of the glass rods 34, 35 is reduced. As shown in the middle figure of 5 (b), the far side of the rolled material 21 can be strongly irradiated. As a result, the rolled material 21
As shown in the left diagram of FIG. 5 (b), it is possible to adjust the reflected light from the lens to be uniform or nearly uniform regardless of the distance x from the glass rods 34, 35.

As shown in FIG. 5C, when the inclined type is employed, the reflected light in the glass rods 34 and 35 is deflected to one side (downward in FIG. The reflected light from the material 21 can be adjusted to be uniform or nearly uniform regardless of the distance x from the glass rods 34, 35 as shown in the left diagram of FIG.

Therefore, in a very simple and low-cost manner,
The end portions 22, 23 can be detected with high accuracy even for the rolled material 21 that does not generate radiation. The result shown in FIG. 3 is the light intensity distribution of the reflected light on the steel strip.

In the above embodiment, the use of the actually used devices has been described in detail. However, the effects of the present invention are not necessarily limited to the specifications of these devices. Applicable to rolled materials of all widths. The cameras 24 and 25 and the cameras 26 and 27 have a viewing angle of 2
The arrangement is not limited to 4 degrees, and the arrangement is not limited to the end 22,
If two cameras are installed every 23, and two cameras are installed with a certain phase difference from each other, the width and position of the strip can be calculated.

Further, the light sources 28 and 29, the optical fiber cables 30 and 31, the glass rods 34 and 35, and the lens 5
The combination of 1, 52 can be made as bright as possible within the permissible range in consideration of the equipment space and environment. The eccentricity and inclination of the optical fiber cables 30, 31 with respect to the centers of the glass rods 34, 35 are as follows:
The adjustment amount differs depending on the positions of the cameras 24, 25 and the cameras 26, 27 and the positions of the glass rods 34, 35, and the reflected light from the ends 22, 23 of the rolled material 21 reaches the cameras 24, 25 and the cameras 26, 27. Sometimes it is adjusted at the time of installation so that it is almost uniform.

[0035]

According to the present invention, there is provided a strip width / meander detection method for hot rolling a steel sheet which detects the width and meander amount of the strip steel from an imaging state obtained by illuminating the strip steel during rolling. In the plate width and meandering detection method, the incident position or the incident angle of the optical fiber cable that transmits light to the glass rod portion of the illumination head is adjusted to give a gradient to the intensity of irradiation light emitted from the illumination head, and from the illumination head. Irrespective of the distance, the intensity distribution of the reflected light from the edge portion of the strip steel is made substantially uniform to detect the width and meandering of the strip steel during rolling. By changing the relative positional relationship between them by shifting or tilting the axis, the light intensity distribution on the irradiation object can be made uniform. As a result, the detection accuracy of the edge portion of the strip steel is remarkably improved, and even for a low-temperature strip steel that does not generate radiation in the conventional method, extremely high-precision edge detection becomes possible. Performance can be significantly improved.

The strip width / meandering detection device of the present invention is a sheet steel hot rolling equipment for detecting the width and meandering of the strip steel from an imaged state obtained by illuminating the strip steel during rolling. An illumination head comprising a lens and a glass rod, a lamp and a condensing device for supplying light to the illumination head, and an optical fiber cable capable of adjusting the incident state on the glass rod. In order to image the edge portion of the strip steel by the reflected light of the light applied to the strip steel, the light source configured by the above, and a pair of two each at the upper portion near both edges of the strip steel. An imaging device that is staggered, a signal processing device that performs arithmetic processing on a signal from the imaging device, and a monitor unit, and the incident position of the optical fiber cable that transmits light to the glass rod unit or Adjusting the angle of incidence to give a gradient to the intensity of the illuminating light emitted from the illumination head, and making the intensity distribution of the reflected light from the edge of the strip steel substantially uniform regardless of the distance from the illumination head during rolling. Since the width and meandering amount of the strip steel are detected, the relative positional relationship between the optical fiber cable and the glass rod is shifted or tilted to change the light intensity at the irradiated object. It is possible to make the distribution uniform. As a result, the detection accuracy of the edge portion of the strip steel is remarkably improved, and even for a low-temperature strip steel that does not generate radiation in the conventional method, extremely high-precision edge detection becomes possible. Performance can be significantly improved.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a plate width / meandering detection device according to an embodiment of the present invention.

FIG. 2 is a light emission distribution diagram of an illumination head.

FIG. 3 is an intensity distribution diagram of reflected light.

FIG. 4 is a schematic configuration diagram of an illumination head.

FIG. 5 is an explanatory diagram of a light path state in a glass rod.

FIG. 6 is an overall configuration diagram of a conventional plate width / meandering detection device.

[Explanation of symbols]

 21 Strip steel plate (rolled material) 22, 23 Edge part (end part) 24, 25, 26, 27 Camera 28, 29 Metal halide lamp light source (light source) 30, 31 Optical fiber cable 32, 33 Illumination head 34, 35 Glass rod 36, 37 Light intensity distribution 41, 42, 43, 44 Cable 45 Image signal input unit 46 Edge detection processing unit 47 Meandering / board width calculation processing unit 48 Monitor unit 51, 52 Lens

Continued on the front page. (72) Inventor Yoji Teramoto 4-6-22 Kannonshinmachi, Nishi-ku, Hiroshima-shi, Hiroshima Mitsubishi Heavy Industries, Ltd. Hiroshima Works (72) Inventor Sumiharu Tazaki 4-622 Kannonshinmachi, Nishi-ku, Hiroshima-shi, Hiroshima No. Mitsubishi Heavy Industries, Ltd. Hiroshima Works

Claims (2)

[Claims] 1. A sheet width and meandering detection method in a hot rolling equipment for steel sheet, wherein a sheet width and meandering amount of the band sheet steel are detected from an imaging state obtained by illuminating the strip steel during rolling. The incidence position or angle of the optical fiber cable transmitting light to the glass rod portion of the illumination head is adjusted to give a gradient to the intensity of the illumination light emitted from the illumination head, and the edge of the strip steel regardless of the distance from the illumination head. A sheet width and meandering amount detecting method for detecting the sheet width and meandering amount of the strip steel during rolling by making the intensity distribution of the reflected light from the part substantially uniform. 2. A strip width and meandering detection device in a hot rolling facility for steel sheets which detects a strip width and a meandering amount of the strip steel from an imaging state obtained by illuminating the strip steel during rolling, An illumination head composed of a lens and a glass rod; a lamp and a condenser for supplying light to the illumination head; and a light source composed of an optical fiber cable capable of adjusting the state of incidence on the glass rod; An imaging device installed in a pair at an upper portion near both edges of the strip steel so as to be imaged at the edges of the strip steel by reflected light of the light applied to the strip steel, two pairs of which are out of phase with each other; The illumination head comprises a signal processing device for arithmetically processing a signal from the imaging device and a monitor unit, and adjusts an incident position or an incident angle of the optical fiber cable for transmitting light to the glass rod unit. Giving a gradient to the intensity of the irradiating light coming out of the strip, and making the intensity distribution of the reflected light from the edge of the strip steel substantially uniform irrespective of the distance from the illumination head, the width and width of the strip steel during rolling. A sheet width and meandering detecting device, wherein a meandering amount is detected.