JP2013246002A - Temperature measuring device for plate to be measured and method for correcting measured temperature - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately measure the temperature of a plate to be measured without requiring a wide space for installation or a complicated device configuration.SOLUTION: A temperature measuring device 1 for a plate W to be measured comprises a reference plate 8, first and second radiation thermometers 9 and 10, a correction coefficient determination means 12, and a temperature calculation means 13. The reference plate 8 is installed while being opposed to one side of the plate W to be measured and a temperature of the reference plate 8 is adjusted to be equal to that of the plate W to be measured. The first and second radiation thermometers 9 and 10 are installed to be oriented from angles which are different from each other, to a measuring point M on one side of the plate W to be measured and are capable of measuring a radiation temperature at the measuring point M, respectively. Based on output from the first radiation thermometer 9 and output from the second radiation thermometer 10, the correction coefficient determination means 12 determines a correction coefficient for correcting a temperature measurement error with shaking of the plate W to be measured. Based on the correction coefficient determined by the correction coefficient determination means 12, the temperature calculation means 13 corrects the output of the first radiation thermometer 9 and the second radiation thermometer 10 and calculates the temperature at the measuring point from corrected output.

Description

  The present invention relates to a temperature measuring device that measures the surface temperature of a plate to be measured formed like a rolled material in a non-contact manner, and a method for correcting the temperature measured by the temperature measuring device.

A continuous heat treatment facility that heats and cools a strip-shaped steel plate (plate to be measured) is provided with a temperature measuring device that measures the temperature of the steel plate. In such a temperature measuring device, a non-contact type radiation thermometer is used.
The radiation thermometer is configured to measure the radiant energy radiated from the measurement point of the plate to be measured and obtain the surface temperature of the measurement point from the measured radiant energy based on the Stefan-Boltzmann law. However, in order to measure an accurate temperature with a radiation thermometer, it is necessary to know the emissivity of the plate to be measured. It is known that this emissivity fluctuates when foreign matter remains on the surface of the plate to be measured or the state of the surface changes.

  Therefore, in on-site temperature measurement such as annealing equipment and hot dip galvanizing equipment, "radiant energy radiated directly from the measurement point (emissivity: ε)" and "radiant energy radiated from the measurement point are the measured plate. , Which is reflected on the roll surface and the reference plate at the same temperature as that and input to the radiation thermometer as the reflected radiant energy (emissivity: 1-ε) "at the same time, canceling the emissivity, A multiple reflection method is used in which the emissivity is 1 and the temperature is obtained.

  By the way, in the multiple reflection method using a roll or a reference plate, when actually measuring the radiant energy and obtaining the temperature, the radiant energy (background radiation) radiated from a member other than the reference plate is measured as an error component. . In particular, under conditions where the plate to be measured vibrates, if the position (layout) of the plate to be measured changes with respect to the reference plate, the amount of background radiation that causes the error will vary greatly, resulting in large measurement errors in the radiation thermometer. Occurs.

  Therefore, in Patent Document 1, one reference plate is installed on each of the front and back surfaces of a steel plate, and the front and back reference plates are arranged so as to be symmetrical with respect to the steel plate. A technique for eliminating a measurement error due to a shake of a plate to be processed by using a radiant temperature signal is disclosed.

JP 2010-38562 A

  By the way, when using the radiation thermometer of patent document 1 mentioned above, it is necessary to each install a reference board on both surfaces of the surface and the back surface of a steel plate. However, in the heat treatment equipment described above, a sufficient space for installing the reference plate may not be secured, and the radiation thermometer as in Patent Document 1 may not be used. In addition, if the measuring device is provided with reference plates on both the front and back sides of the steel plate, not only the structure becomes complicated, but also the price of the device increases.

  The present invention has been made in view of the above-mentioned problems, and accurately measures the temperature of the plate to be measured by reliably eliminating the influence of background radiation without requiring a large installation space or a complicated apparatus configuration. It is an object of the present invention to provide a temperature measuring device for a plate to be measured, and a method for correcting a measured temperature measured by the temperature measuring device.

In order to solve the above problems, the temperature measuring device for a plate to be measured according to the present invention employs the following technical means.
That is, the temperature measuring device for a plate to be measured according to the present invention is installed so as to face one side of the plate to be measured, and the reference plate whose temperature is adjusted to the same temperature as the plate to be measured, and the device to be measured A first radiation thermometer and a second radiation thermometer installed so as to be directed from different angles with respect to the measurement point on one side of the plate and capable of measuring the radiation temperature at the measurement point; Correction coefficient determining means for determining a correction coefficient for correcting a temperature measurement error due to a shake of the plate to be measured, based on the output from the first radiation thermometer and the output from the second radiation thermometer, and the correction Temperature calculating means for correcting the outputs of the first radiation thermometer and the second radiation thermometer based on the correction coefficient determined by the coefficient determining means, and calculating the temperature of the measurement point from the corrected output; Are provided.

Preferably, the correction coefficient determining means may determine the correction coefficient based on a ratio between an output from the first radiation thermometer and an output from the second radiation thermometer.
Preferably, the first radiation thermometer and the second radiation thermometer may have different directivity angles with respect to the measurement point in plan view.
Preferably, the first radiation thermometer and the second radiation thermometer may have different directivity angles with respect to the measurement point in a side view.

Preferably, the plate to be measured is a long material, and the first radiation thermometer is provided on one side when viewed from the center in the width direction of the plate to be measured of the long material, and the second on the other side. A radiation thermometer is preferably provided.
The method for correcting the measurement temperature by the radiation thermometer according to the present invention includes a reference plate that is installed facing one side of the plate to be measured and is temperature-adjusted so as to have the same temperature as the plate to be measured. A first radiation thermometer and a second radiation thermometer installed so as to be directed from different angles with respect to the measurement point on one side of the measurement plate, respectively, and capable of measuring the radiation temperature at the measurement point; When correcting the temperature measured using the temperature measuring device provided with the above, it follows that the measured plate is shaken based on the output from the first radiation thermometer and the output from the second radiation thermometer. A correction coefficient for correcting a temperature measurement error is determined, and outputs of the first radiation thermometer and the second radiation thermometer are corrected based on the determined correction coefficient.

  According to the temperature measuring device for a plate to be measured and the method for correcting the temperature measured by the radiation thermometer according to the present invention, the influence of background radiation is reliably eliminated without requiring a large installation space or a complicated device configuration. The temperature of the measuring plate can be accurately measured.

It is the figure which showed the hot dip galvanization installation provided with the temperature measuring apparatus of this invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a temperature measuring apparatus according to a first embodiment, wherein (a) shows a state before the plate to be measured vibrates, and (b) shows a state after the plate to be measured vibrates. It is a figure. It is a figure which shows the relationship between the measured value of the radiation temperature measured with the temperature measuring apparatus of 1st Embodiment, and a correction coefficient. It is the figure which showed the procedure of the correction method of the measured temperature of 1st Embodiment. FIG. 2 shows a temperature measuring apparatus according to a second embodiment, in which (a) shows a state before the plate to be measured vibrates, and (b) shows a state after the plate to be measured vibrates. It is a figure.

[First Embodiment]
Hereinafter, the temperature measuring device 1 of the plate W to be measured according to the first embodiment will be described with reference to the drawings.
FIG. 1 illustrates a hot dip galvanizing facility 2 provided with the temperature measuring device 1 of the first embodiment. In addition, the hot dip galvanizing equipment 2 is an example, and the temperature measuring device 1 of the first embodiment may be installed in another device.

  The hot dip galvanizing equipment 2 is used for continuously hot-dip galvanizing by passing a steel plate W (measurement plate) that has been rolled in the previous step, and is used to manufacture the galvanized steel plate W. . The hot dip galvanizing facility 2 includes an annealing furnace 3 that heat-treats the steel plate W before plating on the entry side of the facility. Inside the annealing furnace 3, a roll transport mechanism 4 for passing the steel plate W up and down is provided so that the steel plate W can be subjected to heat treatment that also serves as a pretreatment for plating.

  A cooling zone 5 for cooling the steel plate W after the heat treatment is provided on the downstream side of the annealing furnace 3, and the steel plate W after being cooled in the cooling zone 5 is sent to the plating pot 6 through the snout. A molten galvanizing bath is accommodated in the plating pot 6, and the hot-dip galvanized steel plate W in the plating pot 6 is cooled by an air cooling unit 7 located above the plating pot 6, and the next step. Sent to.

In the cooling zone 5 and the air cooling unit 7 described above, it is necessary to accurately grasp the temperature of the steel plate W (measured plate W), and some temperature measuring device 1, for example, a non-contact type radiation thermometer is provided. It is common.
By the way, when trying to measure the temperature of the steel plate W passing through the hot dip galvanizing facility 2 with the radiation thermometer as described above, a large temperature measurement error may occur due to the shake of the steel plate W. For example, in the hot dip galvanizing equipment 2, there is a place where the distance from the upstream guide roll to the one guide roll located on the downstream side is long, and when the temperature of the steel sheet W is to be measured in such a place. The steel plate W may shake greatly and temperature measurement may become difficult.

  That is, in the place as described above, “vibration” in which the steel plate W swings along the thickness direction, “meandering” in which the steel plate W swings in the plate width direction, and “twist” in which the steel plate W twists around the axis in the transport direction. ”Etc. are likely to occur. When these types of vibrations occur in the steel sheet W, the position of the steel sheet W as viewed from the radiation thermometer changes, and the position of the measurement point at which the temperature is to be measured also fluctuates. There is a greater possibility of temperature measurement errors.

  In order to correct such a temperature measurement error, the applicant of the present application has disclosed a temperature measurement device disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 2010-38562), that is, a reference plate and a radiation thermometer on both the front and back surfaces of a steel plate. However, this equipment is relatively large, and mass production equipment such as hot dip galvanizing equipment does not have enough space to install radiation thermometers on both sides of the steel sheet. There are many cases.

  Therefore, in the temperature measuring apparatus 1 of the first embodiment, the reference plate 8 that is temperature-adjusted so as to face the one surface of the steel plate W so as to have the same temperature as the plate W to be measured is provided to cancel the influence of emissivity. I am doing so. Furthermore, in the temperature measuring device 1 of the first embodiment, the first radiation thermometer 9 and the second radiation temperature are directed from different angles with respect to the measurement point M on one side (one side surface) of the steel plate W. A total of 10 are installed. Then, based on the output from the first radiation thermometer 9 and the output from the second radiation thermometer 10, there is provided a calculation means 11 that corrects a temperature measurement error due to the shake of the steel plate W.

The calculation means 11 includes a correction coefficient determination means 12 for determining a correction coefficient for correcting the temperature measurement error, and the first radiation thermometer 9 and the first radiation thermometer 9 based on the correction coefficient determined by the correction coefficient determination means 12. And a temperature calculation means 13 for correcting the output of the radiation thermometer 2 and calculating the temperature of the measurement point M from the corrected output.
Hereinafter, details of the temperature measuring apparatus 1 of the first embodiment will be described.

  FIG. 2 is an enlarged view of the temperature measuring apparatus 1 according to the first embodiment. Specifically, FIG. 2A shows a state before the steel plate W vibrates, and FIG. 2B shows an enlarged state after the steel plate W vibrates. 2 (a) and 2 (b) are both composed of two upper and lower views, and the upper view is a top view of the surface of the steel plate W placed horizontally (plan view), and The figure below is a side view of the steel sheet W.

  The steel plate W is formed in a long strip shape, and FIG. 2A shows the steel plate W that passes through from the right side to the left side of the drawing. As is apparent from the lower diagram of FIG. 2A, a measurement point M (a point indicated by a solid circle) at which the temperature is to be measured is located on the upper surface of the steel plate W. The apparatus 1 is configured to measure the temperature of the upper surface of the steel plate W. Further, above the steel plate W, a reference plate 8 that is shorter in the transport direction than the steel plate W and wider in the width direction is provided.

  The reference plate 8 is disposed so as to be parallel to the steel plate W or at a predetermined inclination with a certain distance upward from one side (upper surface in the illustrated example) of the steel plate W (measurement plate). Yes. The reference plate 8 is a flat plate made of steel or the like. The reference plate 8 is controlled to have the same temperature as the steel plate W (temperature measured with a radiation thermometer) using a temperature adjusting device (not shown).

The reference plate 8 is sufficiently larger than the steel plate W so that the background radiation other than the reference plate 8 is as small as possible when viewed from the measurement point M of the steel plate W so that the influence of background radiation can be reduced. It is preferable to adopt an area.
The first radiation thermometer 9 and the second radiation thermometer 10 are provided between the steel plate W and the reference plate 8 at a certain distance from the steel plate W and the reference plate 8. Has been. And these two radiation thermometers are installed in the direction inclined with respect to the measurement point M on the surface of the steel plate W, and can measure the radiant energy (electromagnetic wave energy) radiated from the measurement point M. Yes. For this radiation thermometer, a sensor capable of sensing radiant energy, such as an infrared sensor, is used.

Next, the installation status (layout) of the first radiation thermometer 9 and the second radiation thermometer 10 and the calculation means 11 which are the features of the temperature measuring device 1 of the present invention will be described.
As shown in FIG. 2 (a), in the radiation thermometer of the present invention, the first radiation thermometer 9 disposed on one side across the center in the width direction of the steel plate W and the other radiation thermometer are disposed. There is a second radiation thermometer 10, and the surface temperature of the same measurement point M can be measured from the left and right sides of the measurement point M in the width direction.

The first radiation thermometer 9 and the second radiation thermometer 10 have the same directivity angle with respect to the measurement point M in a side view, but are different from each other in a plan view. That is, there are two directivity angles of the first radiation thermometer 9 and the second radiation thermometer 10, that is, an elevation angle with respect to the surface of the steel plate W and an inclination angle with respect to the sheet passing line direction. The elevation angles of the two radiation thermometers are the same (θ _s1 = θ _s2 ), but the inclination angles are different from each other (θ ₁ ≠ θ ₂ ).

Based on the output from the first radiation thermometer 9 (indicated value of the measured temperature) and the output from the second radiation thermometer 10 (indicated value of the measured temperature), the calculating means 11 shakes the plate W to be measured. This is to correct the temperature measurement error associated with.
Specifically, the calculation means 11 includes a correction coefficient determination means 12 for determining a correction coefficient, and a temperature indication value measured by each radiation thermometer based on the correction coefficient determined by the correction coefficient determination means 12. Temperature calculating means 13 for correcting the above. The computing means 11 is actually composed of software that operates on a personal computer.

  The correction coefficient determination means 12 determines a correction coefficient for correcting a temperature measurement error due to the shake of the plate W to be measured based on the output from the first radiation thermometer 9 and the output from the second radiation thermometer 10. To do. The output from the radiation thermometer input to the correction coefficient determination means 12 includes not only the result of the temperature indication value measured by each radiation thermometer but also the intensity of the radiation energy measured by the radiation thermometer. It can also be used.

  The output from the first radiation thermometer 9 and the output from the second radiation thermometer 10 are inputted to the correction coefficient determination means 12, and the ratio of the inputted two outputs is taken, or The difference between the outputs is once calculated, the correction coefficient is determined based on the calculated ratio and the difference value, and the determined correction coefficient is sent to the temperature calculation means 13. The reason why the output ratio or difference is used to determine the correction coefficient will be described in detail later.

The temperature calculation means 13 corrects the outputs of the first radiation thermometer 9 and the second radiation thermometer 10 based on the correction coefficient determined by the correction coefficient determination means 12. Then, the temperature calculating means 13 outputs the measured temperature value after correction based on the determined correction coefficient as “corrected measured temperature”.
By the way, the reason why the ratio or difference of the output from the radiation thermometer is used in the correction coefficient determination means 12 described above is as follows.

For example, as shown in FIG. 2A, consider a case where the first radiation thermometer 9 and the second radiation thermometer 10 are installed at positions where the directivity angles with respect to the steel plate W are different from each other. At this time, in FIG. 2A, the elevation angles θ _s of the respective radiation thermometers are the same, but the inclination angles with respect to the plate line direction are different, and the inclination angle of the first radiation thermometer 9 is θ _1. The inclination angle of the second radiation thermometer 10 is θ ₂ (θ ₂ > θ ₁ ).

Under such an apparatus layout, as shown in FIG. 2 (b), when the steel plate W is moved downward by δ due to vibration, the first radiation thermometer 9 of the first radiation thermometer 9 is shown as indicated by a dotted circle in the figure. The position of the measurement point M moves from the position of the solid circle to the upper right, and the position of the measurement point M of the second radiation thermometer 10 moves to the lower right. In the case of the first radiation thermometer 9, the moving distance of the measurement point M is δ in the feed direction of the steel plate W.
/ tanθ _s × cosθ ₁ and δ / tanθ _s × sinθ _{1 in the} plate width direction. The moving distance of the measuring point of the second radiation thermometer 10 M sends direction δ / tanθ _s × cosθ ₂ of the steel sheet _{W, δ / tanθ s × sinθ} 2 next to the plate width direction, the movement of the measuring point M The distance is different for both thermometers.

  In particular, in the first embodiment, the reference plate 8 described above is formed long in the plate width direction of the steel plate W and short in the feed direction so that the area of the reference plate 8 can be made as small as possible. For this reason, even if the measurement point M moves in the plate width direction, the temperature measurement value hardly changes, but when the measurement point M moves in the longitudinal direction, the temperature measurement value tends to change greatly. That is, in the first embodiment, when the measurement point M moves in the longitudinal direction, the temperature measurement value is easily affected.

Therefore, if the radiation thermometer, the reference plate 8 and the steel plate W are arranged as shown in FIG. 2A (hereinafter simply referred to as a layout), each radiation is radiated with respect to the deflection width (amplitude) of the steel plate W. The calculation result of the measured temperature measured by the thermometer is also different.
That is, as shown in FIG. 3A, both the temperature indication value of the first radiation thermometer 9 and the temperature indication value of the second radiation thermometer 10 gradually curve as the amplitude increases. It shows a change trend that increases as you draw. The change in the indicated value of the first radiation thermometer 9 having a small inclination angle θ ₁ is larger in the region where the amplitude is negative than the change in the indicated value of the second radiation thermometer 10 having a large inclination angle θ _2. Change. In this way, the temperature indication value curve of the first radiation thermometer 9 and the temperature indication value curve of the second radiation thermometer 10 are different from each other because of the difference between the installation angles θ ₁ and θ _2. This is due to a change in the amount of radiation and a change in the form factor of the reference plate 8.

By the way, in the actual temperature measuring apparatus 1, it is difficult to measure how much the steel plate W is actually shaken, in other words, the moving distance δ of the steel plate W, and the amplitude shown on the horizontal axis of FIG. It is often impossible to obtain Therefore, it is not realistic to correct the indicated value of the temperature measurement value using the graph as shown in FIG.
Therefore, in the temperature measuring device 1 of the first embodiment, these values are obtained with respect to both the temperature indication value of the first radiation thermometer 9 and the temperature indication value of the second radiation thermometer 10. The ratio is obtained, and the relationship between the obtained ratio (radiation thermometer instruction value ratio) and the moving distance δ of the steel sheet W is obtained.

That is, first, the temperature indication value of the second radiation thermometer 10 (result of the solid line in FIG. 3A) is the temperature indication value of the first radiation thermometer 9 (result of the dotted line in FIG. 3A). When the divided values are summarized as changes with respect to the amplitude, the relationship shown in FIG. 3B is obtained. FIG. 3B shows a change tendency in which the ratio of the temperature indication value gradually decreases with respect to the increase in amplitude.
Based on the relationship between FIG. 3B and FIG. 3A obtained as described above, as shown in FIG. 3C, the relationship of the correction coefficient to the radiation thermometer indicated value ratio is shown. A curve can be obtained. This curve is determined for each of the first radiation thermometer 9 and the second radiation thermometer 10.

  As shown in FIG. 3C, the correction coefficients of the first radiation thermometer 9 and the second radiation thermometer 10 are both “radiation temperature instruction value ratio = temperature instruction value of the first radiation thermometer 9”. If the "radiation temperature instruction value ratio" is calculated, the first radiation thermometer 9 and the second radiation can be easily obtained. The correction coefficient of the thermometer 10 can be obtained accurately and easily.

Further, by using FIG. 3C, the correction coefficient for the radiation thermometer can be calculated without knowing the amplitude δ of the steel plate W, and it is possible to know how much the steel plate W is actually shaken. Even a difficult actual temperature measuring apparatus 1 can be adopted.
As shown in FIG. 3 (c), when the radiation thermometer indicated value ratio is 1 or less, in other words, when the steel plate W approaches the reference plate 8, the correction coefficient changes with a value of about 1 almost. do not do. Therefore, in actual correction, when the radiation thermometer indicated value ratio is 1 or less, the correction may be performed by setting the correction coefficient to 1.

Next, with reference to FIG. 4, a signal processing performed by the above-described calculation means 11, in other words, a method for correcting the measured temperature by the radiation thermometer of the present invention will be described.
First, in step 1 (S1), the reference plate 8 is installed on one side of the steel plate W so as to be substantially parallel to the steel plate W. The reference plate 8 is provided with a temperature adjusting device capable of adjusting the temperature so that the temperature of the reference plate 8 matches the temperature of the steel plate W. A temperature sensor for measuring the temperature of the reference plate 8 is also prepared separately.

In step 2 (S2), the first radiation thermometer 9 and the second radiation thermometer 10 are attached to the steel sheet W at different angles. Then, the first radiation thermometer 9 and the second radiation thermometer 10 measure the temperature at the measurement point M on the surface of the steel sheet W.
In step 3 (S3), it is determined whether or not the indication value of the second radiation thermometer 10 is fluctuating with respect to the indication value of the first radiation thermometer 9. Here, when it is determined that the indication value of the second radiation thermometer 10 has sufficiently fluctuated with respect to the indication value of the first radiation thermometer 9 (the difference between both indication values exceeds a desired value) Is considered to have a large temperature measurement error due to the shake of the plate W to be measured, and proceeds to step 4 for correction. On the other hand, if it is determined that there is no fluctuation, the temperature measurement error is negligible (correction of the indicated value is not necessary), and the process proceeds to step 7.

  In step 4 (S4), both instructions are obtained by dividing the measured temperature instruction value Tm2 measured by the second radiation thermometer 10 by the measured temperature instruction value Tm1 measured by the first radiation thermometer 9. The value signal ratio m (= Tm2 / Tm1) is calculated. The radiation thermometer having a small angle with respect to the steel plate W is the first radiation thermometer 9, and the radiation thermometer having a large angle with respect to the steel plate W is the second radiation thermometer 10.

  In step 5 (S5), using the signal ratio m obtained in step 4 described above and FIG. 3C, the correction coefficient R1 (m) of the first radiation thermometer 9 corresponding to this signal ratio m. The correction coefficient R2 (m) of the second radiation thermometer 10 is determined. Further, the measured value Tm01 and the second radiation temperature of the first radiation thermometer 9 excluding the influence of the vibration of the steel plate W as the measurement object using the determined correction factors R1 (m) and R2 (m). A total of ten measurement values Tm02 are obtained.

Next, an average value of the measured value Tm01 of the first radiation thermometer 9 and the measured value Tm02 of the second radiation thermometer 10 obtained in step 5 is obtained (S6), and the obtained average value is corrected. The plate temperature Ts is obtained as the instruction value Tm (S8).
Even when it is determined in step 3 that there is no significant fluctuation between the two indication values, the average value of the measurement value Tm01 of the first radiation thermometer 9 and the measurement value Tm02 of the second radiation thermometer 10 is calculated. Obtaining (S7), and using the obtained average value as the corrected instruction value Tm, the plate temperature Ts is obtained based on a method based on the multiple reflection method (for example, the method disclosed in Patent Document 1) (S8).

According to the temperature measuring device 1 for the plate W to be measured and the method for correcting the temperature measured by the radiation thermometer, the number of reference plates 8 to be installed is only one side of the steel plate W, so that a large space is required for installing the temperature measuring device 1. Is not required, and a complicated apparatus configuration is not required. Therefore, it is possible to accurately measure the radiation temperature of the steel sheet W by reliably and easily eliminating the influence of the background radiation while having a simple configuration.
“Second Embodiment”
Next, the temperature measuring device 1 for the measurement target plate W according to the second embodiment will be described.

As shown in FIG. 5, in the temperature measuring apparatus 1 of the second embodiment, the directivity angles of the first radiation thermometer 9 and the second radiation thermometer 10 with respect to the measurement point M are the same in a plan view, and a side view. Are different from each other.
That is, as shown in FIG. 5A, the first radiation thermometer 9 and the second radiation thermometer 10 are both at the same angle θ ₁ with respect to the feeding direction of the steel plate W, but the first radiation The elevation angle of the thermometer 9 is θ _s1 , the elevation angle of the second radiation thermometer 10 is θ _s2 (θ _s2 > θ _s1 ), and the respective inclination angles are different from each other.

Therefore, as shown in the lower diagram of FIG. 5B, when the steel sheet W moves downward by δ due to vibration, the measurement point M of the first radiation thermometer 9 is measured as indicated by the dotted line in the drawing. The position is shifted farther than the position of the measurement point M of the second radiation thermometer 10 (the position away from the plate line and the edge in the width direction). Specifically, in the case of the first radiation thermometer 9, the moving distance of the measurement point M is δ / tanθ _s1 × cosθ _{1 in} the feed direction of the steel plate W and δ / tanθ _s1 × sinθ _{1 in the} plate width direction. Become. Further, the moving distance of the measurement point M of the second radiation thermometer 10 is δ / tanθ _s2 × cosθ _{1 in} the feeding direction of the steel plate W and δ / tanθ _s2 × sinθ _{1 in the} sheet width direction.

That is, even in the layout of the second embodiment described above, since the elevation angles are different from each other, the first radiation thermometer 9 and the second radiation thermometer 10 are directed at different angles with respect to the measurement point M. Become. As a result, when the steel sheet W moves by the distance δ, the measured temperatures of the respective radiation thermometers show completely different changing trends. Therefore, in the second embodiment as well, the measurement temperature is corrected using the correction means determined based on the output means from the calculation means 11 described in the first embodiment, in other words, the respective radiation thermometers. Thus, the radiation temperature of the steel sheet W can be accurately measured.

Note that the arrangement of the first radiation thermometer 9 and the second radiation thermometer 10 may be a layout in which the first embodiment and the second embodiment are combined. That is, the directivity angles of the respective radiation thermometers with respect to the measurement point M are different in a plan view (θ ₁ ≠ θ ₂ ), and in addition, they are also different from each other in a side view (θ _s1 ≠ θ _s2 ). Good. Even in this case, the change in the measured temperature with respect to the moving distance δ of the steel plate W is completely different for each radiation thermometer, and the correction as described above is possible.

In the temperature measuring apparatus 1 of the present invention, both the first radiation thermometer 9 and the second radiation thermometer 10 are provided only on one side (for example, the right side) with the center in the width direction of the steel plate W interposed therebetween. May be. Even if two radiation thermometers are arranged on the right side of the steel plate W and not arranged on the left side, the directivity angles of the respective radiation thermometers with respect to the measurement point M are different in plan view (θ ₁ ≠ θ _2). ), If they are different from each other in the side view (θ _s1 ≠ θ _s2 ), the change in the measured temperature with respect to the moving distance δ of the steel plate W becomes completely different in each radiation thermometer, and the correction as described above is possible. Because it becomes.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. In particular, in the embodiment disclosed this time, matters that are not explicitly disclosed, for example, operating conditions and operating conditions, various parameters, dimensions, weights, volumes, and the like of a component deviate from a range that a person skilled in the art normally performs. Instead, values that can be easily assumed by those skilled in the art are employed.

DESCRIPTION OF SYMBOLS 1 Temperature measuring device 2 Hot-dip galvanization equipment 3 Annealing furnace 4 Roll conveyance mechanism 5 Cooling zone 6 Plating pot 7 Air cooling part 8 Reference board 9 1st radiation thermometer 10 2nd radiation thermometer 11 Calculation means 12 Correction coefficient determination means 13 Temperature calculation means M Measuring point W Steel plate (measurement plate)

Claims (7)

A reference plate that is installed to face one side of the plate to be measured and is temperature-adjusted to be the same temperature as the plate to be measured,
A first radiation thermometer and a second radiation thermometer installed so as to be directed from different angles with respect to the measurement point on one side of the plate to be measured, and capable of measuring the radiation temperature at the measurement point, respectively. When,
Correction coefficient determining means for determining a correction coefficient for correcting a temperature measurement error due to the shake of the plate to be measured, based on the output from the first radiation thermometer and the output from the second radiation thermometer;
Based on the correction coefficient determined by the correction coefficient determining means, the temperature calculation for correcting the output of the first radiation thermometer and the second radiation thermometer and calculating the temperature of the measurement point from the corrected output. Means,
A temperature measuring device for a plate to be measured, comprising:   The correction coefficient determination unit determines the correction coefficient based on a ratio between an output of the first radiation thermometer and an output of a second radiation thermometer. Temperature measuring device for the plate to be measured.   3. The temperature measuring device for a measured plate according to claim 1, wherein the first radiation thermometer and the second radiation thermometer have different directivity angles with respect to the measurement point in plan view. .   4. The measurement target plate according to claim 1, wherein the first radiation thermometer and the second radiation thermometer have different directivity angles with respect to the measurement point in a side view. 5. Temperature measuring device.   The measured plate is a long material, and the first radiation thermometer is provided on one side when viewed from the center in the width direction of the measured plate of the long material, and the second radiation temperature is provided on the other side. A temperature measuring device for a plate to be measured according to any one of claims 1 to 4, wherein a meter is provided.   6. The temperature measuring device for a measured plate according to claim 1, further comprising temperature adjusting means for adjusting the temperature of the reference plate so that the temperature of the reference plate is the same as that of the measured plate. A reference plate that is placed facing one side of the plate to be measured and is temperature-adjusted so that it has the same temperature as the plate to be measured, and is directed from different angles with respect to the measurement point on one side of the plate to be measured The temperature measured using a temperature measuring device provided with a first radiation thermometer and a second radiation thermometer each capable of measuring the radiation temperature at the measurement point is corrected. On the occasion
Based on the output of the first radiation thermometer and the output of the second radiation thermometer, a correction coefficient for correcting a temperature measurement error due to the shake of the plate to be measured is determined, and based on the determined correction coefficient, A method for correcting a measured temperature, wherein outputs of the first radiation thermometer and the second radiation thermometer are corrected.