JP2765452B2 - Method of measuring furnace deformation of industrial furnace - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring furnace body deformation in an industrial furnace, and more particularly to a method for measuring furnace body deformation in an industrial furnace capable of measuring furnace body deformation in a furnace.

[0002]

2. Description of the Related Art Furnace walls of industrial furnaces such as coke ovens, blast furnaces, and heating furnaces are constructed of refractory materials, but the influence of heat is caused by contact with a material to be treated and the like, resulting in damage such as erosion and cracks. May occur. Since this damage ultimately affects the life of the furnace, it is necessary to perform repairs at an appropriate timing. One of the indicators to determine the damage situation is the deformation of the refractory constituting the furnace as shown below. A method of measuring volume / expansion is used.

[0003] For example, the furnace body of a coke oven is made of bricks and is operated at a temperature of about 1100 to 1300 ° C. Causes of the aging of the coke oven include a change in the furnace temperature due to a change in the operation rate, a change in the furnace temperature due to coal charging, carbonization, and discharge from the kiln, an expansion pressure during coal carbonization, and a pressure on the furnace wall for coke extrusion. It is believed that these causes damage and breaks such as joint breaks and cracks in the brick, eventually leading to furnace shutdown. Of these damages, crack growth is a numerical value that reflects the extension of the furnace body in the furnace length direction, so by measuring the furnace direction length at regular intervals, the furnace body expansion, that is, the progress of crack growth Can be grasped quantitatively. Therefore, it is necessary to accurately measure the furnace length in order to estimate the furnace life of the coke oven body and take appropriate countermeasures against aging.

Conventionally, the coke oven furnace length was measured by
As disclosed in JP-A-39136, the distance to the surface of the furnace fastener or the protection plate is measured indirectly using a transit from a reference point provided outside the furnace. Alternatively, as disclosed in JP-A-3-24509, a method is used in which the extruder-side furnace port and the fire extinguisher-side furnace port are measured using a laser displacement meter, thereby measuring the elongation of the entire furnace. Had been.
However, these methods have the following problems, for example. First, heat distortion occurs in the metal which is the protection plate of the furnace lid due to aging, and it is difficult to extract only the amount of change due to the elongation of the brick. Next, due to abnormal protrusion of the transition part of the furnace, a gap has been created between the protective plate and the brick surface,
It is difficult to extract only the change due to the elongation of the brick. Furthermore, in the method disclosed in Japanese Utility Model Application Laid-Open No. 61-39136, errors are likely to occur due to individual differences because the measurement is performed manually. These problems are the same in the case of other industrial furnaces other than coke ovens. Therefore, as shown in JP-A-6-229684, the wall of the internal refractory of the furnace to be measured is measured. A method has been proposed in which a marker that can be used as a mark for length measurement is provided, and the relative positional relationship is obtained.

FIG. 19 is a view for explaining the measurement principle. Referring to FIG. 19, markers 2A and 2B are provided at predetermined intervals on the refractory wall surface in the furnace of coke oven 1, which is an industrial furnace. Note that the number of markers is not limited to two and may be any number. A measurement rack 3 is provided along the refractory wall in the coke oven 1, and observation windows 4A and 4B are provided on the measurement rack 3 at portions facing the markers 2A and 2B, respectively. Measurement rack 3
In order to image the vicinity of the markers 2A and 2B, an imaging device 5 whose optical axis is parallel to the furnace length direction is provided therein, and the beam splitter 14 whose reflection surface is inclined by 45 ° with respect to the optical axis of the imaging device 5 and A mirror 13 is provided in a direction facing the markers 2A and 2B. Further, in the measuring rack 3,
A distance measuring device 6 for measuring a distance between an arbitrary reference point 15 and a center point of a portion imaged by the imaging device 5 is provided. The reference point 15 shown in FIG. 11 is the position of the distance measuring device 6 itself.

[0006] The imaging device 5 captures images 7A and 7B near the markers 2A and 2B. In the image 7A, X ₁ and Y ₁ which are the local positions of the marker 2A are imaged.
At B, X ₂ and Y ₂ which are local positions of the marker 2B are imaged. In addition, the image 7 in the case of measuring a local position
The X-axis direction of A and 7B is the furnace length direction. Distance measuring device 6
An image 7 which distance L ₁ and the marker 2B in the origin and reference point 15 in the image 7A marker 2A is captured is captured
Measuring the distance L ₂ between the origin and reference point 15 in the B.
The measured X ₁ , Y ₁ , X ₂ , Y ₂ , L ₁ , and L ₂ are input to the signal processing device 8, and the positional relationship between the marker 2A and the marker 2B with respect to the reference point 15 is calculated.

FIG. 20 shows a reference point 15 and markers 2A and 2B.
It is a figure which shows the positional relationship of. Referring to FIG.
Using the reference point 15 set at the position of the
If the coordinate system taking the x-axis in the direction is an xy coordinate system,
In the xy coordinate system, the positional relationship between the markers 2A and 2B (x
₁ , Y₁ ) And (x_Two , Y_Two ) Is as in equation (1)
expressed. The position coordinates of these markers 2A and 2B (x₁ , Y
₁ ) And (x _Two , Y_Two ) At regular intervals
The marker movement distance is measured, and this value is used as a substitute for the amount of furnace body expansion.
Not only can it be a table value, but also in the furnace length direction
Horizontal between certain markers and perpendicular to furnace length
The vertical relative distance between markers,
It is obtained by using equation (2). Using this method
For example, since the length of the members that make up the furnace is directly measured,
Japanese Unexamined Patent Publication No. Hei 3-245509, Japanese Utility Model Application Laid-Open No. 61-39136
Can solve the problem.

[0008]

(Equation 1)

[0009]

By the way, in the measuring method shown in FIGS. 19 and 20, the imaging optical axis after reflection by the mirror 13 and the beam splitter 14 of the imaging device 5 for imaging the marker is to be observed. In the case of being perpendicular to the wall surface, that is, if the reflection surfaces of the mirror 13 and the beam splitter 14 are inclined by 45 ° with respect to the optical axis, no measurement error occurs.

However, it is difficult to accurately incline a mirror or the like at an angle of 45 ° with respect to the optical axis, and a gantry incorporating an image pickup device for picking up a marker must always be inserted in a high-temperature furnace in a fixed direction. Is very difficult. Even if it is possible, if the observation direction changes slightly due to thermal stress etc. while continuing the measurement, it will be measured as if it changed, even if the distance between the markers does not actually change A measurement error occurs.

Therefore, the present invention solves the above-mentioned problem, and even if the angle of inclination of the mirror or the like is not 45 ° with respect to the optical axis of the image pickup device or the like, the mirror or the like may have a slight attitude. An object of the present invention is to provide a method for measuring the deformation of a furnace body of an industrial furnace, which can accurately determine a relative positional relationship between markers even when a positional shift occurs.

[0012]

According to a first aspect of the present invention, there is provided a method for measuring the deformation of a furnace body of an industrial furnace, wherein the industrial furnace is provided with a plurality of marks provided on a wall surface in the industrial furnace. Through the reflecting means in the furnace, image a predetermined range including each mark part, and measure the local position of each mark part in the captured image, while the distance between each reflecting means and a predetermined reference point And measuring the distance between each mark portion using each local position and the distance between each reflection means and the reference point, a furnace body deformation measurement method of an industrial furnace, wherein each reflection means has its position and A member capable of expressing the amount of change in posture is provided, and each mark portion is determined by using a local position of each mark portion in a predetermined range imaged and a measured distance between each reflection unit and a predetermined reference point. A first step of calculating the relative position of A second step of capturing the image of the member and calculating the amount of change in the position and orientation of each reflecting means, and calculating the relative amount of each of the mark portions in accordance with the calculated amount of change in the position and attitude of each reflecting means. And correcting the target position.

According to a second aspect of the present invention, each of the reflecting means of the first aspect is provided with a plurality of measurement points, and the second step is to measure a distance between the reference point and each of the measurement points, Calculating the amount of change in the attitude of each reflecting means in accordance with the value and a predetermined arithmetic expression.

According to a third aspect of the present invention, each reflecting means of the first aspect is provided with a plurality of measuring points, and measures a distance between a reference point and each measuring point. A distance between the means and a predetermined reference point is calculated.

According to a fourth aspect of the present invention, there is provided a method for measuring a furnace body deformation of an industrial furnace, comprising: a reflecting means in the industrial furnace provided corresponding to a plurality of mark portions provided on a wall surface in the industrial furnace; A first step of imaging a predetermined range including each mark portion, and measuring a local position of each mark portion in the captured image, a position of each reflection means, and a three-dimensional imaging optical axis. A second step of imaging a member capable of expressing a rotation angle with one of the coordinate axes as a rotation axis and calculating a change amount of the position and the rotation angle of each reflection unit; A third step of measuring a distance between the obtained plurality of measurement points and a predetermined reference point, and calculating a change amount of the rotation angle with respect to the other two axes on the three-dimensional coordinate axis; The position and rotation angle of each reflection means calculated in step A fourth step of calculating a distance between the reference point and each of the reflection means according to a distance between each measurement point and a predetermined reference point, and a rotation angle of each reflection means calculated in the second and third steps And correcting the local position of each mark portion measured in the first step according to the distance between the reference point calculated in the fourth step and each reflecting means.
And the local position of each mark portion corrected in the fifth step, the reference point calculated in the fourth step, and the distance between each reflection means, and the relative position between each mark portion is calculated. And a sixth step.

[0016]

According to a first aspect of the invention, there is provided a method for measuring furnace body deformation of an industrial furnace, wherein a predetermined range including a plurality of mark portions provided on a wall surface in the industrial furnace is imaged through a reflecting means, and an image in the image is obtained. Measure the local position of each mark part, measure the distance between each reflection means and a predetermined reference point, measure the local position of each mark part and the distance between each reflection means and a predetermined reference point, Is used to calculate the relative position of each mark portion, and further, by imaging the members provided in each reflecting means, the amount of change in the position and posture of each reflecting means is calculated, and each is calculated according to the amount of change. The relative position of the mark can be corrected.

According to a second aspect of the present invention, in the method for measuring the deformation of a furnace body of an industrial furnace, a distance between a plurality of measurement points provided on each reflection means and a predetermined reference point is further measured. According to the arithmetic expression, the amount of change in the attitude of each reflecting means can be calculated more accurately.

According to a third aspect of the present invention, in the method for measuring the deformation of a furnace body of an industrial furnace, a distance between a plurality of measuring points provided on each reflecting means and a predetermined reference point is further measured, and based on the measured value. A more accurate distance between each reflecting means and a predetermined reference point can be calculated.

According to a fourth aspect of the present invention, in the method for measuring furnace body deformation of an industrial furnace, a predetermined range including a plurality of mark portions provided on a wall surface in the industrial furnace is imaged through each reflecting means, and an image in the image is obtained. By measuring the local position of each mark portion and imaging a plurality of measurement points and members provided on each reflection means, the position of each reflection means and the distance between each reflection means and a predetermined reference point are calculated. ,
Correct the local position of each landmark part with the calculated value,
The relative position of each mark portion can be calculated from the corrected value, the calculated reference point, and the distance between each reflecting means.

[0020]

FIG. 1 is a diagram for explaining an outline of the principle of a method for measuring the deformation of a furnace body of an industrial furnace according to one embodiment of the present invention. Hereinafter, portions different from the principle of the conventional furnace body deformation measuring method of the industrial furnace shown in FIG. 11 will be described.

Referring to FIG. 1, image pickup device 5 includes a mirror 13
And markers 2A and 2B via beam splitter 14
The vicinity is imaged, but the mirror 13 and the beam splitter 14
In order to measure the posture, cross scales 16B and 16A are attached to the mirror 13 and the beam splitter 14, respectively. Although a cross-shaped scale was used as the scale, the shape of the scale is not limited to this.

The distances L ₂ and L ₁ between the mirror 13 and the beam splitter 14 and an arbitrary reference point 15 are measured by a distance measuring device 6 composed of a transit or the like. On the other hand, the imaging device 5 provided outside the furnace captures images 7A and 7B near the markers 2A and 2B via the mirror 13 and the beam splitter 14, and the visual field of the markers 2A and 2B in the images 7A and 7B. Coordinates Z ′ ₁ , Y ′ ₁ , Z ′
_2, Y _'2 is measured. Note that the markers 2A and 2B
The coordinate system in the field of view will be described later in detail. Further, the imaging device 5 captures images 7C and 7D of the mirror 13 and the beam splitter 14, respectively, and outputs the images 7C and 7D.
The positions and orientations of the mirror 13 and the beam splitter 14 are measured from the states of the scales 16A and 16B in D. Using the measurement values obtained from the distance measurement device 6 and the imaging device 5 in this manner, the signal processor 8 calculates the distance between the markers corrected for the change in the position and orientation of the mirror 13 and the beam splitter 14. Find the relative distance of Therefore, by periodically measuring the relative distance between the markers, the amount of change in the furnace body deformation can be obtained.

FIG. 2 is a diagram for explaining a method of detecting a change in the position and attitude of the mirror 13 obtained from the image of the scale 16B captured by the image pickup device 5 accompanying the image.

Referring to FIG. 2, three assumptions are made to simplify the description. First, attention is paid only to the mirror 13 among the beam splitter 14 and the mirror 13 to which the scales 16A and 16B are attached. Next, in the initial state (image of the scale 16B on the mirror 13 in a state where the position and the posture do not change) 18A, the scale 16B
And the optical axis of the imaging device 5 coincide with each other.
The angle between the reflection surface and the optical axis is 45 °. Next, it is assumed that the vertical and horizontal lengths of the scale are known. Based on this assumption, the following can be shown. For example, the scale 16 in the image in the initial state 18A
In order to make the lengths S _Y and S _Z of B equal, the actual length of the scale 16B is S _O and the width is S _O /
The scale 16B may be manufactured so that cos is 45 °. Thus, if the depth of focus of the lens of the imaging device 5 is sufficiently large, the relationship of S _Y ≒ S _Z can be established. Moreover, later be described, the initial state 18A of the scale provided on the mirror with an attitude that is offset from the vertical length of the measurement values S _'Y, measurement of lateral length S' _Z met Then, it is possible to satisfy S _Y = S ′ _Y / cos φ = S _Z.

The case where the mirror 13 has been rotated from the initial state 18A by the angles of rotation θ, φ, η, respectively,
The following assumption is made in order to describe the case where the object moves in parallel in the horizontal direction (the Z-axis direction in the drawing) or the vertical direction (the Y-axis direction in the drawing). In the initial state 18A, the point at which the reflection surface of the mirror 13 intersects with the optical axis of the imaging device 5 is set as the coordinate origin, the optical axis of the imaging device 5 is the X axis (the imaging direction is positive), and the furnace wall direction is the Z axis (furnace). Assume an XYZ coordinate system in which the wall direction is positive) and the direction perpendicular to the drawing is the Y axis. It is assumed that the rotation around the Y axis is θ, the rotation around the Z axis is φ, and the rotation around the X axis is η, and the sign of the rotation direction is as shown in FIG.

First, in the case of θ rotation (image 18B), the horizontal length S ′ _Z of the scale 16B in the observation image 18B decreases when rotated in the positive θ direction in the figure, and rotates in the negative direction. It will increase. Therefore, if the relationship of Expression (3) is used, θ is expressed as Expression (4). Next, in the case of η rotation (image 18C), the rotation angle η from the initial state in the observation image 18C is detected as η as it is.

Next, in the case of φ rotation (image 18D), if φ is minute (about −5 ° <φ <5 °), the rotation angle φ of the horizontal line of the scale 16B in the observation image 18D
_{Using 1} and η, φ is detected as φ = φ ₁ + η.
More precisely, φ is represented by an expression as shown in Expression (5).

Next, in the case of horizontal movement (image 18E)
At the scale 16 detected in the observation image 18E
Displacement D _Z from the initial state of B is directly detected as a parallel movement amount in the horizontal direction. Then, in the case of vertical movement (image 18F), the displacement amount D _Y from the initial state of the scale 16B that are detected in the observation image 18F is directly detected as a parallel movement amount in the vertical direction. As described above, by measuring the scale 16B, a change in the position (D _Z , D _Y ) and a change in the posture (θ, φ, η) of the mirror 13 are detected.

[0029]

(Equation 2)

FIG. 3, FIG. 4, FIG. 5 and FIG.
FIG. 4 is a diagram for explaining a relative positional relationship between B and a mirror 13;

The attitude (θ, φ, η) of the obtained mirror 13
First, in order to calculate the position of the marker 2B from the marker coordinates on the marker image, the relationship between the coordinate system used for detecting the attitude of the mirror 13 and the marker coordinates on the marker image will be described with reference to FIG. explain. As shown in FIG. 3A, an XYZ coordinate system is orthogonally projected on a wall surface of a coke oven virtual image 1 'where a marker virtual image 2B' which is a virtual image of the marker 2B is present.
The axis corresponding to the axis is Z 'axis, and the axis corresponding to the Y axis is Y'
Assume an axis. Based on this assumption, as shown in FIG. 3B, in the image 7B in which the marker 2B is imaged, if the marker virtual image 2B ′ is viewed from the camera principal point 21 of the imaging device 5, the marker coordinate is (Z ′ _2). , Y ′ ₂ ). Here, it is required how many mm the width or height of the image actually corresponds to. However, they may be calculated based on, for example, the characteristics of the camera lens and the distance W + L, or may be calculated from the ratio of a scale having a known length to the field width.

Next, referring to FIG. 4, in the XYZ coordinate system having the origin at the intersection of the reflecting surface of the mirror 13 and the optical axis of the imaging device 5, the reflecting surface of the mirror 13 is expressed by the following equation (6). Is represented by However, θ ′ = 45 ° −θ, and the following description will be made using θ ′ to simplify the description. In the drawing, L ′ is the camera principal point 21 of the imaging device 5 and the origin O
W is the distance between the origin O and the wall surface of the coke oven 1, as well as the distance between the intersection O and the marker image 7B. Assuming that the marker virtual image 2B 'is obtained on the marker image 7B by the imaging device 5 as shown in FIG. 5 and FIG. 6, in the XYZ coordinate system, the marker coordinates 2B' (Z ' ₂ , Y' ₂ direction vector N to the), N = (W, Y '2, Z' 2) - (- L ', 0,
0) = (W + L ′, Y ′ ₂ , Z ′ ₂ ). Therefore, since the unit vector M with respect to the direction vector N is expressed by Expression (7), the expression of a straight line connecting the camera viewpoint 21 and the marker virtual image 2B 'is expressed by Expression (8).

[0033] Therefore, the (8) and a straight line represented by the formula intersection P _m with the equation (6) in the represented plane is expressed as the equation (9). Equation of a straight line connecting the marker 2B provided on the intersection point P _m and the plane of the coke oven 1 can be expressed as the equation (10). Therefore, if Z = W is substituted for the expression (10), the relative position of the marker 2B with respect to the mirror 13 is calculated as represented by the expression (11).

[0034]

(Equation 3)

[0035]

(Equation 4)

As described above, if the marker coordinates of the measured marker image are known, the marker coordinates _PT can be obtained. In terms of the measurement principle, the unknowns represented by Equations (6) to (11) are
θ, φ, η, L ′, and W. Among these unknowns, L ′ is determined by a value measured by the distance measuring device 6 as follows:
It can be given as a separation distance on the optical axis of the imaging device from the camera principal point 21 of the imaging device 5 to the mirror 13. Further, W can be given as a design value from the optical axis to the wall surface of the coke oven 1, or can be given as a value measured by a distance meter such as a laser distance meter for measuring the distance to the wall surface.

FIGS. 7 and 8 are diagrams for explaining the distance correction required when measuring the distance to the mirror and the beam splitter based on the distance measurement value. Hereinafter, a description will be given using a lightwave distance meter as a distance measuring device.

Referring to FIG. 7, corner cubes 23 and 24 for reflecting light waves output from light wave distance measuring instrument 22 provided outside the furnace are provided on mirror 13 and beam splitter 14, respectively. This corner cube 2
When the mirrors 3 and 24 are mounted on the frames 25 and 26, for example, the relative positional relationship between the mirror 13 and the corner cube 23 and between the beam splitter 14 and the corner cube 24 becomes constant. In addition, FIG.
As shown in (b) and (c), even when the attitude of the corner cube 24 (23) changes with respect to the observation optical axis of the lightwave distance measuring instrument 22, the distance measuring points of the corner cube 24 (23) itself. The distance L _Pc to P _C is always measured. However, as shown in FIG. 7, for example, the optical axis of the imaging device 5 and the reflection surfaces of the mirror 13 and the beam splitter 14 are 45
In the initial state at an angle of °, the corner cube 24
(23) when the distance measuring point P _C is located away h _C with respect to the vertical above or below the optical axis of the imaging device 5 of the distance measurement value L _Pc corrected to the true distance L _R (L _R = L ₁ , L ₂ ). That is, in rotation in the θ direction, −
It is necessary to correct D _Z tan (45 ° −θ), and in the rotation in the φ direction, − (h _C −D _Y / cos (φ)) ·
Correction of sin (φ) is required, and no correction is required for rotation in the η direction. Based on the correction thus obtained, a true distance L _R as shown in Expression (12) is obtained.

For distance measurement, a distance meter such as an interferometer or a magnescale can be used in addition to the lightwave range finder. In this case, the distance measurement can be similarly corrected.

[0040]

(Equation 5)

The measured values based on the measurement principle shown in FIGS. 1 to 8 are L ₁ and L ₂ measured by the distance measuring device 6.
And (Z ′ ₁ , Y ′ ₁ ) marker coordinates obtained from each image near the marker obtained by the imaging device 5.
(Z ′ ₂ , Y ′ ₂ ) and the respective attitudes of the mirror 13 and the beam splitter 14 obtained from the scale image obtained by the imaging device 5 (θ ₁ , φ ₁ , η ₁ ), (θ
₂ , φ ₂ , η ₂ ) and the position changes of the mirror 13 and the beam splitter 14 obtained from the scale image obtained by the imaging device 5 (D _Z1 , D _Y1 ), (D _Z2 , D _Y2 ).
It is. By using these values, correction can be performed even when the position and orientation of the mirror or the beam splitter have changed, and when the relative distance between markers is determined using equations (1) and (2). Can be obtained with higher accuracy than.

The wall surface of the coke oven 1 is desirably horizontal to the optical axis of the imaging device 5 as an observation device, and the distance between the oven wall and a mirror may be any known value. It can also be measured using a distance measuring device.

In order to improve the accuracy of the correction, it is desirable to use an imaging device having a large depth of focus and capable of obtaining an image with the highest possible resolution, and the image resolution of the signal processing device is also possible. As high a resolution as possible is desirable.

FIG. 9 is a diagram for explaining an outline of an embodiment of the measuring method according to the present invention.

Referring to FIG. 9, a measuring rack 3 as an insertion device in coke oven 1 is provided with a mirror 13 and a beam splitter 14, and a television as imaging device 5 provided outside coke oven 1. The camera is connected to the markers 2A and 2A via the mirror 13 and the beam splitter 14.
An image near B is captured. Further, the reflecting surfaces of the mirror 13 and the beam splitter 14 form an angle of about 45 ° with respect to the imaging direction of the television camera, and the television camera sets the positions of the markers 2A and 2B reflected by the mirror 13 and the beam splitter 14. An image is taken by adjusting the focal length. The television camera captures images of the scales 16B and 16A attached to the reflecting surfaces of the mirror 13 and the beam splitter 14 by adjusting the focal length.

On the other hand, corner cubes 9A and 9B are provided for the mirror 13 and the beam splitter 14, respectively, and the lightwave distance measuring devices 10A and 10B provided outside the coke oven 1 themselves have the corner cubes 9A and 9B. The distance to 9B is measured.

The corner cube is provided so that the relative positional relationship with the mirror or the beam splitter is always constant, and the light wave rangefinders 10A and 10B are provided.
Are provided such that their optical axes are parallel to the optical axis of the imaging device.

FIG. 10 is a diagram for explaining the relationship between the image resolution and the accuracy of the furnace body expansion measurement when the mirror 13 is rotated in the θ direction (in the horizontal plane).
It is explained that the resolution required as an imaging device depends on the required accuracy of measuring the amount of furnace body expansion.

The relationship between the movement amounts ΔL and θ at the intersection between the optical axis of the imaging device 5 and the furnace wall surface is expressed by equation (13). In addition,
W in Expression (13) represents the distance between the optical axis of the imaging device 5 and the furnace wall. When the mirror 13 is accurately tilted by 45 ° with respect to the optical axis of the imaging device 5, the size of the scale is represented by L _S ,
Assuming that the size of the scale after θ rotation is L ′ _S ,
4) It is possible to consider the relationship represented by the equation, for example, W
= 200 mm, Equation (13) and (1)
By using the expression 4), values as shown in Table 1 are obtained. Thus, if the required accuracy is 1 mm, ΔL <0.
Since it is necessary to detect θ of about 0.3 ° with 1 mm, it can be seen that the image requires the minimum horizontal resolution of the value shown in Expression (15).

[0050]

(Equation 6)

[0051]

[Table 1]

FIG. 11 is a diagram for explaining the outline of the principle of a method for measuring the deformation of a furnace body of an industrial furnace according to another embodiment of the present invention. Hereinafter, portions different from the principle of the furnace body deformation measuring method of the industrial furnace according to the embodiment shown in FIG. 1 will be described.

Referring to FIG. 11, in order to more accurately measure the distance between arbitrary reference point 15 and mirror 13 and the distance between arbitrary reference point 15 and beam splitter 14, measurement point P21 is applied to mirror 13 at the same time. , P22, P23 are provided,
Measurement points P11, P12, P13
Is provided. The positions at which these measurement points are provided will be described later in detail.

The imaging device 5 captures images 7A and 7B in the vicinity of the markers 2A and 2B via the mirror 13 and the beam splitter 14, and stores the images of the markers 2A and 7B in the images 7A and 7B.
A, 2B, coordinates Z ′ ₁ , Y ′ ₁ ,
Z ′ ₂ and Y ′ ₂ are measured. Further, the imaging device 5
Image 7 of each of mirror 13 and beam splitter 14
C and 7D are imaged, and a scale 16 in the images 7C and 7D is taken.
The position of each of the scales 16A and 16B, which is immediately detected from the state of A and 16B, which is the deviation from the coordinate origin, and the rotation angle of the imaging device 5 with the imaging optical axis as the rotation axis are measured. This measured result is input to the signal processor 8.

On the other hand, the distance measuring device 6 composed of a transit or the like causes the measuring point P1
1, P12, P13, P21, P22, the distance to _{P23 L 11, L 12, L} 13, L 21, L 22, L 23 is measured.
The respective distances measured in this way are input to the signal processor 8, and calculations described in detail later are performed, and the rotation angles θ and φ defined in FIG. 2 are derived. The signal processor 8
An accurate relative position between the mirror 13 and the beam splitter 14 is calculated based on the input measurement value, and a position of the marker 2B with respect to the mirror 13 and a position of the marker 2A with respect to the beam splitter 14 are calculated. The distance between the marker 2A and the marker 2B is calculated.

FIG. 12 is a view for explaining a method of detecting a rotation angle η representing the position and orientation of the mirror 13 accurately obtained from the image of the scale 16B captured by the image pickup device 5 and accompanying the image. .

Referring to FIG. 12, here also, FIG.
The assumptions made in the above are made to simplify the explanation. That is, first, of the beam splitter 14 and the mirror 13 to which the scales 16B and 16B are attached,
Attention is focused only on 3. Next, in the initial state 19A, the center of the scale 16B and the optical axis of the imaging device 5 match, and the angle between the mirror 13 and the optical axis is 45 degrees. Next, it is assumed that the vertical and horizontal lengths of the scale 16B are known.

In the initial state 19A, the mirror 1
The point at which the reflection surface of the imaging device 5 intersects with the optical axis of the imaging device 5 is defined as the coordinate origin, the optical axis of the imaging device 5 is the X axis (the imaging direction is positive), the furnace wall direction is the Z axis (the furnace wall direction is positive), Assume an XYZ coordinate system in which the vertical direction is the Y axis with respect to the drawing. The rotation angles θ, η, and φ are as shown in FIG.

Of the rotation angles θ, η, and φ,
What is detected immediately is the case of η rotation (image 19
B) only. This is as described above.
The rotation angle η from the initial state 19A in the observation image 19B is
It is detected as it is as η. Then get by rotation
The rotation angles that can be obtained immediately besides the rotation angle η
In the case of horizontal movement (image 19C),
The case of the direction movement (image 19D) will be described. This 2
In the two cases, the displacement D_Z,
D_YIs obtained as it is. In other words, for horizontal movement
In the case (image 19C), it is detected in the observation image 19C.
Displacement D from the initial state of scale 16B _ZIs as it is
Detected as the amount of horizontal translation, and
Even in the case (image 19D), the displacement amount from the initial state 19A
D_YIs detected as a vertical translation amount.
You.

As described above, the positional displacements D _Z and D _Y of the mirror 13 with respect to the initial state 19A from the observed images 19B, 19C and 19D obtained by the imaging device 5 and the displacement of the rotation angle η representing the attitude. Is detected.

FIGS. 13 and 14 show a reference plane which is a plane perpendicular to the optical axis of the imaging device 5 through the reference point 15 and the measurement points P21, P22, P23 provided on the mirror 13 by the distance measuring device 6. FIG. 4 is a diagram for explaining a method of detecting respective distances from measurement points P11, P12, and P13 provided on a beam splitter 14; In particular, FIG. 13 is an enlarged view of a main part in FIG. 11 and a side view of the inside of the industrial furnace, and FIG. 14 is a plan view seen from the AB line direction in FIG.

Referring to FIG. 13 and FIG.
A plane that passes through the optical axis 5 and is perpendicular to the optical axis of the imaging device 5 is defined as a reference plane 41. Then, the measurement points P11, P12, P1
3 is provided on the beam splitter 14, and the measurement points P21,
P22 and P23 are provided on the mirror 13, and the distance measuring device 6 is provided at a predetermined position on the reference plane 41 to measure the distance between each measurement point and the reference plane 41. Note that the number of measurement points is not limited to these numbers,
It suffices that three or more reflecting means be provided. The distance measuring device 6 includes a reference plane 41 and measurement points P11 and P1.
L, which is the distance from 2, P13, P21, P22, P23
_11, to measure the _{L 12, L 13, L 21} , L 22, L 23. At this time, the number of distance measuring devices 6 may be prepared by the number of measuring points, or may be one. In the case of one,
By moving on the reference plane 41, the distance to each measurement point is measured.

FIG. 15 shows the camera viewpoint 2 of the image pickup device 5 using the distances between the measurement points P21, P22, P23 of the mirror 13 obtained by the distance measurement device 6 and the reference plane 41.
FIG. 16 is a diagram for explaining the calculation of the distance between 1 and the coordinate origin O. FIG. 16 is a diagram for explaining the positional relationship between the measurement points P21, P22, and P23 provided on the mirror 13.

Referring to FIG. 15 and FIG.
The description will be simplified by focusing on the mirror 13 of the beam splitter 3 and the beam splitter 14.

As shown in FIG. 16, the initial state (mirror 13
In a state where there is no change in the position and posture of the scale 16B), the measurement point P21 is separated from the center of the scale 16B by HMirr / 2 upward.
The measuring points P22 and P23 are provided on the frame 31 to which the mirror 13 is fixed.
They are provided on the frames 32, 33, which are separated by Mirr / 2 and downwardly by HMrr / 2. further,
At this time, it is assumed that the measurement points P21, P22, and P23 are provided such that the plane formed by the measurement points P21, P22, and P23 is the same plane as the reflection plane of the mirror 13. With such a configuration, even if the mirror 13 rotates or moves from the initial state, and the posture or position of the mirror 13 changes, the measurement points P21, P22, and P23 remain at the mirror 1
3, the relative positional relationship is maintained.

When the position and orientation of the mirror 13 change from the initial state, the origin O, which is the intersection between the optical axis of the imaging device 5 and the reflecting surface of the mirror 13, always coincides with the center of the mirror 13 as shown in FIG. Not necessarily. Therefore, in order to calculate the distance L ₂ between the origin O of the reference plane 41 and the mirror 13, first above the measuring point and the reference plane 41 by way P
21, P22, to measure the distance L _21, L _22, L ₂₃ and P23. Then, measurement points P22, P2 as shown in FIG.
3 and the measurement point P2
If the distance WMirr between the measurement point P2 and the measurement point P23 is measured in advance and is known, the rotation angles θ and φ of the mirror 13 in the coordinate system shown in FIGS. 17) Calculated by equation.

The rotation angle η representing the attitude of the mirror 13
Is not obtained by this calculation, the measured value obtained by imaging the scale 16B with the imaging device 5 may be used as the rotation angle η.

The arrangement of the measurement points P21, P22 and P23 is as shown in FIG. 16, and the rotation angles θ and φ are calculated using HMirr and WMirr representing the positional relationship. However, the present invention is not limited to this. However, if there is a parameter that can represent a relationship in which a plurality of measurement points are arranged, the rotation angles θ and φ can be obtained according to the parameter and another arithmetic expression.

Further, here, for simplicity, only the mirror 13 has been described. However, according to the positional relationship between the measurement points P11, P12, and P13 provided on the beam splitter 14 and a predetermined arithmetic expression, the beam Splitter 1
The rotation angles θ and φ representing the posture of No. 4 are calculated.

Next, a method for obtaining the distances L ₁ and L ₂ between the reference plane 41 and the intersection between the optical axis of the imaging device 5 and the angular reflection surface of the mirror 13 or the beam splitter 14 will be described. Here, for the sake of simplicity, attention is focused on the mirror 13. Referring to FIG. 15, when mirror 13 is imaged by imaging device 5 in the initial state, scale 16B provided on mirror 13 is configured as shown in FIG.
6, the measurement points P21, P
22 and P23 are also provided on the frames 31, 32 and 33, respectively. Then, the mirror 13 changes its position and orientation, and the rotation angle θ, φ, θ, the center of the mirror 13 with respect to the optical axis of the imaging device 5 (scale 1
Position of 6B center) D _Z, the respective distances L ₂₁ to D _Y and the reference plane 41 measurement points P21, P22, P23,
It is assumed that L ₂₂ and L ₂₃ have been obtained.

First, as in the embodiment shown in FIG. 4, in the XYZ coordinate system with the origin O at the intersection of the reflection surface of the mirror 13 and the optical axis of the imaging device 5, the reflection surface of the mirror 13 ) Expression. Where θ ′ = 45 ° −θ
In the following, the description will be made by appropriately using θ ′ in order to simplify the description.

Measurement points P21, P22, P on mirror 13
23 are arranged as shown in FIG.
Distance L from quasi-plane 41 to the center of scale 16B
_SCBecomes as shown in Expression (18). Accordingly
And the distance L that needs to be calculated_TwoIs given by equation (18)
Obtained distance L_SC, Used to satisfy equation (6).
Component n of the normal vector n_X, N_Y, N_ZAnd mirror
Movement amount D of position 13_Y, D _ZThe calculation using
It is obtained as shown in equation (19). The distance obtained here
Release L_TwoIs the distance between the reference plane 41 and the origin O
This distance L_TwoIs the camera viewpoint 21 of the imaging device 5 and the origin
If it matches the distance to O, the distance L_TwoIs the distance L '
Then, it is substituted into the equation (7), and the equations (8) to (12) are substituted.
This operation is performed.

However, as shown in FIG.
Camera viewpoint 21 is not on reference plane 41 and the distance between
The separation is dL (f_Two) If you were far away,
The distance between the origin O and the camera viewpoint 21 is as shown in equation (20).
become. Note that the distance dL (f _Two) Is one of the reference planes 41
Assuming that the right direction when the point is the origin is a positive value, FIG.
5 indicates a negative value. Similarly,
Light of the imaging device 5 on the reflection surface of the beam splitter 14
Distance L ′ between the intersection with the axis and the camera viewpoint 21 of the imaging device 5
₁Is expressed as in equation (21).

Next, the rotation angles (θ, φ, η) representing the attitude of the mirror 13, the distance L ′ ₂ from the lens viewpoint 21 to the origin O on the reflection surface of the mirror 13, and the marker 2B coordinates (Y based on the _'2, Z' _2), a method is described for calculating the position of the marker 2B in the mirror 13. Note that the position of the marker 2A with respect to the beam splitter 14 is obtained in the same manner by the following method, and a description thereof will be omitted.

As shown in FIGS. 5 and 6, the marker 2B
Assuming that a marker virtual image 2B ', which is a virtual image of the marker virtual image 2B', is obtained on the marker image 7B by the imaging device 5, the marker virtual image coordinates 2B 'from the camera viewpoint 21 in the XYZ coordinate system.
The direction vector N to (Z ′ ₂ , Y ′ ₂ ) is N = (W,
Y ′ ₂ , Z ′ ₂ ) − (− L ′ ₂ , 0,0) = (W + L ′
_2, Y is represented by _'2, Z' _2). Therefore, the unit vector M with respect to the direction vector N is represented by the following equation (7). Hereinafter, by performing a process similar to the calculation process in the above-described embodiment, the relative position of the marker 2B with respect to the mirror 13 as represented by Expression (11) is calculated.

If the marker coordinates of the marker image thus measured are known, the marker coordinates _PT can be obtained. The unknowns on the measurement principle are θ, φ, η,
L ′ and W. Among these unknowns, L ′ is L ₁₁ , L ₁₂ , L obtained as a measured value based on the distance measured value 6.
_13, L _21, determined by calculation based on L _22, L _23.
W is given as a design value from the optical axis to the observation wall,
It can also be given as a measured value by a distance measuring device such as a laser distance meter used for measuring the distance to a wall surface.

Further, a measurement value is used to determine an unknown value.
What is obtained is the value measured by the distance measuring device 6.
L₁₁, L₁₂, L₁₃, L_{twenty one}, L_{twenty two}, L_{twenty three}And the imaging device 5
Markers obtained from each image near the obtained markers
Coordinates (Z '₁, Y '₁), (Z '_Two, Y '_Two)
And from the scale image obtained by the imaging device 5.
Changes in the position of the mirror 13 and the beam splitter 14
There is (D_Z1, D_Y1), (D_Z2, D_Y2) And the imaging device 5
Therefore, the mirror 13 and the mirror 13
Representing one of the attitudes of each of the beam splitters 14
₁, Η_TwoAnd the calculated value is L₁₁, L₁₂, L₁₃, L
_{twenty one}, L_{twenty two}, L_{twenty three}13 and beams obtained from
Θ representing each posture of the splitter 14₁, Φ₁And θ
₁, Φ_TwoIt is. Marker coordinates, which are measured values
(Z '₁, Y '₁), (Z '_Two, Y_Two) And mirror 13
Each position of the beam splitter (D_Z1, D_Y1), (D
_Z2, D _Y2) Values are not actually obtained directly from the image
Given by the pixel, which is the quantization number of each image
Shall be. Measure the measurements taken by the pixels to the actual dimensions
In order to match with, how many millimeters a pixel corresponds to
In other words, the visual field width (or visual field height) of the obtained image is known.
Must use the methods described below.
I just need to be.

As a first method, utilizing the characteristics of the imaging device 5 and assuming that the focal length of the imaging device 5 is constant,
Since there is a certain relationship between the distance to the object and the obtained visual field width, the visual field width at the time of imaging can be obtained by examining in advance the characteristics of the imaging device 5 that determines the relation.
Next, as a method of using the size of the scale in the image, if the focal length of the imaging device 5 is constant when the scale is imaged, the proportion occupied by the scale in the image decreases in contrast to the increase in the distance. Therefore, if the size of the scale is known in advance, the visual field width (height) of the obtained image can be obtained. Further, as another method, the furnace wall surface is obtained by using the visual field width (height) W _S when observing the scale and the characteristic value C _S = visual field width (height) / distance representing the characteristics of the imaging device 5. Viewing width (height) W when observed by the imaging device 5
_W is obtained by the relationship of Expression (22).

Using the above calculation results, the relative positions between the markers shown in FIG. 1 have the values shown in Expression (23), and such values are calculated at regular intervals. Thus, the movement amount between the markers is measured, and this can be used as a representative value of the furnace body expansion amount. Also, reference plane 4
If 1 is installed outside the furnace, the amount of movement of each marker based on that is measured, so that it can be regarded as not the amount of movement of the marker but the amount of deformation of each marker installation site.

Also in this embodiment, it is desirable that the wall surface of the coke oven 1 is horizontal to the optical axis of the imaging device 5 as an observation device, and that the distance between the oven wall and the mirror should be known. It can also be measured by using a distance measuring device such as a laser distance meter.

Further, an example has been described in which two mirrors are used as the reflection means (a total reflection mirror and a beam splitter). However, the number of reflection means is not limited to this. For example, one total reflection mirror and a plurality of It is also possible to apply two or more reflecting means such as a beam splitter, and if a measurement is to be performed with one reflecting means, a mechanism for moving the reflecting means in order to image each marker is provided. If
This is possible.

Further, although it seems that the above description does not consider the phenomenon that the optical axis of the imaging device is refracted by the beam splitter, the influence of the optical axis change depends on the process of calculating the position of the local marker and the distance. There is no accuracy problem due to the offset between the process of calculating L ₁ and L ₂ .

[0083]

(Equation 7)

FIGS. 17 and 18 are diagrams for explaining the outline of another embodiment of the measuring method according to the present invention.
In particular, FIG. 17 is a side view of the inside of the industrial furnace, and FIG.
FIG. 17 is a plan view seen from the CD direction in FIG. 16.

Referring to FIGS. 16 and 17, a measuring rack 3 as an insertion device in coke oven 1 has mirror 13
And a beam splitter 14 are provided.
The television camera which is the imaging device 5 provided outside the
Images near the markers 2A and 2B are captured via the mirror 13 and the beam splitter 14. Further, the reflecting surfaces of the mirror 13 and the beam splitter 14 form an angle of about 45 ° with respect to the imaging direction of the television camera,
The TV camera is a mirror 13 and a beam splitter 14
The images of the markers 2A and 2B reflected on the image are captured by adjusting the focal length.

The mirror 13 is provided with a corner cube 43A at the upper part, and the corner cube 43B,
43C is provided. Similarly, the beam splitter 14 is provided with a corner cube 44A on a lower side, and corner cubes 44B and 44C on an upper side. Then, the lightwave distance measuring devices 10A and 10B provided outside the coke oven 1 measure the distance from the reference plane 41 to each corner cube. Further, each of the scales 16B and 16A attached to the mirror 13 and the reflecting surface of the beam splitter 14 also captures an image by adjusting the focal length of the television camera for observing the marker.

The corner cube is manufactured so that the relative positional relationship with the mirror or the beam splitter is always constant. At this time, the optical axes of the lightwave distance measuring device and the imaging device are always parallel. Created to be.

Although optical components such as mirrors, beam splitters and corner cubes and their supporting members are housed in a rack, there are no electronic components, so even if a rack having relatively small heat insulation and cooling ability is used. There is an advantage that it is good.

Further, in addition to the optical axis of each of the optical distance measuring devices and the optical axis of the image pickup device, the direction in which the rack is inserted by the moving mechanism should be as parallel as possible.

[0090]

As described above, according to the present invention, the position and orientation of the reflecting means can be detected by observing the members and measuring points attached to the reflecting means. The relative position between the landmarks can be corrected in accordance with the amount of change in the temperature. It is possible to accurately perform maintenance management such as reflection to a replacement time by improving accuracy.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a measurement principle of a furnace body deformation measuring method of an industrial furnace according to one embodiment of the present invention.

FIG. 2 is a diagram for explaining a method of obtaining a change amount of a mirror position and a posture by imaging a scale of FIG. 1;

FIG. 3 is a diagram for explaining a relationship between a coordinate system in a mirror in FIG. 1 and coordinates in a marker image;

FIG. 4 is a first diagram illustrating a relative position between a mirror and a marker in FIG. 1;

FIG. 5 is a second diagram for describing a relative position between the mirror and the marker in FIG. 1;

FIG. 6 is a third diagram illustrating the relative position between the mirror and the marker in FIG. 1;

FIG. 7 is a first diagram for explaining correction of a distance measurement distance with respect to a change in the attitude of a mirror in FIG. 1;

FIG. 8 is a second diagram for explaining correction of the distance measurement distance with respect to a change in the attitude of the mirror in FIG. 1;

FIG. 9 is a diagram for explaining a furnace body deformation measuring method of an industrial furnace according to one embodiment of the present invention.

FIG. 10 is a diagram for explaining the influence of a change in the attitude of a mirror on measurement.

FIG. 11 is a view for explaining an outline of a principle of a method of measuring a furnace body deformation of an industrial furnace according to another embodiment of the present invention.

FIG. 12 is a diagram for explaining a method of obtaining a change amount of a mirror position and a posture by imaging the scale of FIG. 11;

FIG. 13 is a first diagram for explaining correction of a distance measurement distance with respect to a change in the attitude of the mirror in FIG. 11;

FIG. 14 is a view as seen from a direction AB in FIG. 13;

FIG. 15 is a second diagram for describing correction of the distance measurement distance with respect to a change in the attitude of the mirror in FIG. 11;

FIG. 16 is a diagram for explaining the arrangement of measurement points on the mirror in FIG. 11;

FIG. 17 is a view for explaining a furnace body deformation measuring method of an industrial furnace according to another embodiment of the present invention.

FIG. 18 is a view as seen from line CD of FIG. 17;

FIG. 19 is a first diagram for explaining a measurement principle of a conventional furnace body deformation measurement method for an industrial furnace.

FIG. 20 is a second diagram for describing the measurement principle of the conventional furnace body deformation measurement method for an industrial furnace.

[Explanation of symbols]

Reference Signs List 1 coke oven 2A, 2B marker 5 imaging device 6 distance measuring device 8 signal processing device 9A, 9B, 23, 24, 43a, 43b, 43c, 4
4a, 44b, 44c Corner cubes P11, P12, P13, P21, P22, P23 Measurement points 10A, 10B, 22 Lightwave range finder 13 Mirror 14 Beam splitter 15 Reference point 16A, 16B Scale 41 Reference plane

Claims (4)

(57) [Claims] An image of a predetermined area including each of the mark portions is taken through reflecting means in the industrial furnace provided corresponding to a plurality of mark portions which can be marks provided on a wall surface in the industrial furnace. Measuring the local position of each mark portion in the captured image, measuring the distance between each of the reflecting means and a predetermined reference point, and measuring each local position and the distance between each of the reflecting means and the reference point. A furnace body deformation measuring method for an industrial furnace for obtaining a distance between respective mark portions using a distance, wherein each of said reflecting means is provided with a member capable of expressing an amount of change in its position and posture, and A first step of calculating a relative position of each mark portion by using a local position of each mark portion in the range and the measured distance between each reflection unit and a predetermined reference point; An image of the member provided on the reflection means is taken, and the position of each reflection means and A second step of calculating an amount of change in posture, and a third step of correcting the calculated relative position of each mark portion in accordance with the calculated amount of change in position and posture of each reflecting means. A furnace body deformation measuring method for an industrial furnace, comprising: 2. The method according to claim 1, wherein a plurality of measurement points are provided in each of the reflection units, and the second step measures a distance between the reference point and each of the measurement points, and compares each of the measured values with a predetermined value. The method for measuring the deformation of a furnace body of an industrial furnace according to claim 1, further comprising a step of calculating an amount of change in the attitude of each reflection unit according to an arithmetic expression. Further, each of the reflecting means is provided with a plurality of measuring points, and measures a distance between the reference point and each of the measuring points. The method according to claim 1, wherein the distance between the reference points is calculated. 4. A predetermined range including each of the mark portions is imaged via reflecting means in the industrial furnace provided corresponding to a plurality of mark portions which can be marks provided on a wall surface in the industrial furnace. A first step of measuring a local position of each mark portion in the captured image; a position of each of the reflection means; and an imaging optical axis as one of three-dimensional coordinate axes, and using this as a rotation axis. A second step of imaging a member capable of expressing a rotation angle to be calculated, and calculating a change amount of a position and a rotation angle of each of the reflection units; and a plurality of measurement points provided in each of the reflection units and a predetermined reference. The distance between the points is measured, and another two points on the three-dimensional coordinate axis are measured.
A third step of calculating a change amount of the rotation angle with respect to the axis; a position and a rotation angle of each reflecting means calculated in the second and third steps; and each measured point and a predetermined reference. A fourth step of calculating a distance between the reference point and each of the reflecting means according to a distance between the points; a rotation angle of each of the reflecting means calculated in the second and third steps; A fifth step of correcting a local position of each mark portion measured in the first step according to a distance between the reference point and each of the reflecting means calculated in the step of; Calculating a relative position between the mark portions based on the local position of each mark portion corrected in the step and the distance between the reference point and each reflecting means calculated in the fourth step. Furnace body deformation of an industrial furnace, including steps Way measurement.