JPS58105008A - Radiation thickness gauge - Google Patents

Abstract

PURPOSE:To provide a titled thickness gauge which measures a thickness at a measuring point in the proximity of a plate end without any delay in answering and without being influenced by a lateral deflection, by a method wherein an output of a plate end detector is compared with outputs of a setter for each measuring point and a setter for returning point, and based on the comparing result, a measuring point and a returning point are determined. CONSTITUTION:A radiation thickness gauge is set so that is positioned at a center of an object 91 to be measured through movement of a C-frame 21, and based on a signal from a line central detecting switch 60, a profile computing part 50 finds a plate thickness of a central part. A C-frame truck 21 is then moved by means of a profile measuring command signal FS from the outside, a comparing circuit 73 outputs a coincidence signal when reaching a speed changing point (a), and the truck 21 is reduced in a moving speed. The output of the plate end detector 25 is normally supplied to a comparing circuit 42 which outputs a coincidence signal when the truck 21 reaches a measuring point (b), and the profile comparing part 50 finds a plate thickness of an edge part. Finally, if the truck 21 moves forward and a coincidence signal is outputted from a comparing circuit 92, the truck 21 is moved backward.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to an improvement in a radiation thickness meter for measuring the profile of, for example, rolled steel plates.

TECHNICAL BACKGROUND OF THE INVENTION In general, rolled steel plates often have a round shape as shown in FIG. Such a gently rounded crown-shaped steel plate is suitable for use as a cooling coil.

For this reason, recent rolling technology employs the work roll bending method in finishing rolling mills to improve rolling reduction and rolling pitch.

A rolled steel plate with an optimum round amount (plate thickness distribution) is produced by appropriately selecting a roll cooling method or the like.

On the other hand, radiation thickness gauges have kept pace with the progress of rolling technology, and are capable of measuring not only the central thickness of copper plates, but also the crown amount (-b -7) in the width direction of steel plates, and the wezzo fit (-〇- ) and Esso Drop lids, etc. are being measured. Such a measurement is called a profile measurement method. In the figure,
a is the thickness of the left esso portion, b is the thickness of the center portion, and C is the thickness of the right edge portion.

Hereinafter, a conventional radiation thickness meter equipped with a glofill measuring means will be described with reference to FIGS. 2 to 5. First, FIG. 2 is a diagram showing the mechanical configuration. In the same figure, 1
1 is a C-frame truck, and this truck 1 is moved in the direction of arrow A in the figure by a truck driving motor 2. A radiation source 3 and a radiation detector 4 (ionization chamber) are arranged opposite to each other on the lower frame 1a and the upper frame 7b of this C-frame truck I. Therefore, when the steel plate 6 is located outside the truck I as shown in FIG. 2, the C-frame truck I is moved to the right in the figure by the drive of the truck drive motor 2. At this time, radiation is being emitted from the radiation source 3. This radiation is the steel plate 6
However, as the thickness of the steel plate 6 increases, the amount of attenuation increases in proportion to the thickness, and the radiation dose decreases.

Next, FIG. 3 is a block diagram of a signal processing system, and the radiation emitted from the radiation source 3 is detected by the radiation detector 4 either directly or via the steel plate 6. This radiation detector 4 converts the current signal into a current signal proportional to the radiation dose, which is then amplified by a preamplifier 7. The analog signal amplified by the preamplifier 7 is supplied to an A-D conversion circuit 8 and a plate thickness detection circuit 9. This A-D conversion circuit 8 digitizes the input analog signal and supplies it to the subsequent signal processing circuit IO. The signal processing circuit 10 calculates the deviation between the digitized code and the preset thickness of the center 5 part of the steel plate 6, and transmits the deviation signal to the subsequent D-A.
It is supplied to the conversion circuit 11. Further, the signal processing circuit 10 sends an average value signal of the no-plate signal and the preset central plate thickness to the plate thickness detection circuit 9. When the signal from the preamplifier 7 exceeds the average value signal, the board thickness detection circuit 9 rises as shown in FIG. 4(b), outputs a false cloth signal, and resets the counter 12. After being reset by the temporary fabric signal, the counter 12 counts the signal from the cart position detector 5 and sends it to the comparator circuit 13 as a cart position signal. This comparison circuit 13 compares the position signal with the measurement point a or C (edge thickness position) set in advance by the measurement point constant device I4, and when they match, profiles the edge thickness measurement timing signal of the steel plate 6. It is given to the arithmetic unit 15. Here, the profile calculation section 15 calculates the crown amount and wedge amount of the steel plate 6 based on the analog signal converted by the DA conversion circuit 11 and the position signal from the comparison circuit I3, and performs profile measurement. FIG. 4(j) shows the shape of the steel plate.

6- Problems in the Background Art With conventional devices, it is possible to accurately detect the board edge using the root signal and extract a signal corresponding to the board width, but in order to do so, it is necessary to use the C frame as shown in Figure 5. It is necessary to make the trolley I wait at a point B without a plate and move it forward toward the copper plate 6 from that position to obtain a root signal. C indicates the flow direction of the steel plate. This causes a delay in the deviation output obtained from the DA conversion circuit 11, as shown in FIG. 4(c). This delay is caused by the time constant caused by the resistors and capacitors built into the detector 4 and preamplifier 7, as well as by the measurement system components.
This is caused by the next lag element. For this reason, it is generally necessary to move the cart 1 from a state without a plate until it reaches a level corresponding to the thickness of the steel plate 6 before starting the actual measurement. For this reason, for example, with a radiation thickness needle having a time constant of 300 msec, when measuring a two-day steel plate 6 at a cart speed of 30 ta/sec, it is impossible to measure within about 20 meters from the edge of the plate.

Further, if lateral vibration or fluctuation in the plate width occurs in the steel plate 6 after the radiation thickness meter detects the plate end and before reaching the measurement point of the setter 14, the measurement point will move relatively. Therefore, when determining the measurement point accurately, measurement point a is
, b, etc., and then the measurement point C is determined on the return trip, but the position correction for this is troublesome. Normally, a medium-sized electronic computer performs distance tracking calculations using signals from a radiation thickness meter and a plate width meter separately installed downstream of the thickness meter to perform position correction.

Purpose of the Invention The present invention has been made in view of the above-mentioned circumstances, and it is possible to measure the measurement point at the end of the object to be measured without response delay, and also to measure the glofil without being affected by shadow changes such as lateral vibration of the object to be measured. The purpose is to provide a radiation thickness gauge.

SUMMARY OF THE INVENTION The present invention provides a plate end detector outside the cart position detector at a predetermined location of a cart equipped with a radiation detection system, and when the cart is located at the center of the line of the object to be measured, the center plate of the object to be measured is detected. To measure the thickness of the object to be measured, to lie it, and to determine the measurement point at the end of the object to be measured and the turning point of the cart from the output of the edge detector, to measure the thickness of the esso part of the object to be measured, and to control the turning of the cart. This aims to achieve the above objectives.

Embodiment of the Invention FIGS. 6 and 7 are diagrams showing an embodiment of the present invention, in which FIG. 6 shows a mechanical configuration and FIG. 7 shows a signal processing system. First, the mechanical configuration of the radiation thickness meter will be described. In FIG. 6, 21 is, for example, a C-frame truck, which is movable. This C
Lower frame 21a of frame truck 2I and its lower frame 21
A radiation source 22 and a light source 23 are respectively arranged on one side of a. In addition, the upper frame 2 of the C frame trolley 2I
1b and one side of its upper frame 21b is a radiation source 22.
A radiation detector 24, such as an ionization chamber, for detecting the amount of radiation from the light source 23 and a plate end detector 25 for detecting the presence or absence of light from the light source 23 are respectively arranged. Note that a radiation source 22. is provided on the upper frame 2Ib side. The light source 23 is placed on the lower frame 21a side, and the radiation detector 2 is placed on the side of the lower frame 21a.
4. A configuration in which the plate edge detectors 25 are respectively arranged may also be used.

In the figure, 26 is a motor for driving a cart, and 27 is a cart position detector. The plate edge detector 25 uses, for example, an IJ near array camera.

Next, the signal processing system is configured as shown in FIG. This signal processing system includes a radiation measurement system 30, a measurement point detection section 40, a profile calculation section 50, a line center detection switch 60 that detects the line center of the object to be measured using a limit switch, etc., and a speed change detection section 70. , a truck control section 80, a truck return detection section 90, and a truck drive motor 26.

The radiation measuring system 30 calculates the deviation from the signal detected by the radiation detector 24 and the preset signal of the center plate thickness of the object to be measured, and determines the center plate thickness and edge of the object to be measured. Outputs a signal for part thickness. That is, this radiation measurement system 30 includes a radiation source 2
A radiation detector 24 that detects the radiation dose from 2 and converts it into an electrical analog signal is provided, and this radiation detector 2
The output of 4 is amplified by preamplifier 31. An A-D conversion circuit 32 is connected to the output side of the preamplifier 31,
Here, the amplified output is converted into a digital signal and supplied to the subsequent signal processing circuit 33. This signal processing circuit 33 is
- When a digital signal is received from the D-conversion circuit 32, a deviation is calculated from the digital signal and a preset signal of the thickness of the center part of the object to be measured, and the deviation signal is used as a signal for the subsequent D-
The configuration is such that the signal is supplied to the A conversion circuit 34, where it is converted into an analog signal and input to the profile calculation section 50.

Next, the measurement point detection section 60 detects the measurement point opening shown in FIG. 8 (corresponding to the edge part plate thickness &, e in FIG. 1). This detection unit 6o sets the distance from the plate edge to the plate edge detector 25, which continuously measures a certain range around the measurement point opening, that is, the measurement point 1, that is, a or both a and c in Fig. 1. It is comprised of a measurement point setter 4I and a comparison circuit 42 that compares the output of the board end detector 25 and the set value of the measurement point setter 41 and outputs a coincidence signal when they match. In response to the matching signal, the profile calculation unit 50 calculates the thickness measurement value of the plate to be measured;
In other words, find the edge plate thicknesses a and c in FIG.

Next, the speed change control section 70 has a function of detecting the speed change point A shown in FIG. 8 and providing a deceleration command signal to the bogie control section 80. That is, this speed change control section 70 includes, for example, a bogie position detector 27 having a 4' las transmitter that outputs a 4' lus that corresponds to the rotational speed of a pinion gear engaged with a position detection rack, and a line center detector. switch 6
After being reset with the signal from 0, the bogie position detector 27
an up/down counter 71 that measures the pulses of and outputs a position signal from the center of the line, a speed change point setter 72 that sets the speed change point A, and a trolley including the line center CL (see Figure 8). It consists of a comparison circuit 73 that compares the position signal and the speed change point set value, and the coincidence signal of this comparison circuit 73 is supplied to the bogie control section 80 as a deceleration command signal. This bogie control section 80 has a function of giving a signal for speed control to the bogie drive motor 26 in accordance with information about the line center CL, speed change point A, and turning point C.

The bogie U1 return detection section 90 includes a return black film gauge 9 that sets the output of the board end detector 25 and the return point C shown in FIG.
This configuration is such that a comparison circuit 92 compares the output of the output signal 1 with the output of the output signal 1, and outputs a match signal when they match. When the trolley control unit 80 receives the match signal from the comparison circuit 92, it outputs a backward speed signal to the trolley drive motor 26.

Next, the operation of the radiation thickness meter configured as above will be explained. Normally, the radiometric thickness is set so that the central axes of the radiation source 22 and the radiation detector 24 are aligned to the center of the object to be measured 91 due to the movement of the C frame 21.

Therefore, at this time, the profile calculation section 50 calculates the center plate thickness from the output of the radiation measurement system 30 based on the signal 13- of the line center detection switch 6o. The measurement operation in this case is as follows. That is, the radiation emitted from the radiation source 22 passes through the plate 91 to be measured and reaches the radiation detector 2.
4. The radiation detector 24 converts the incident radiation dose into an electrical analog signal proportional to the amount of radiation, and supplies the signal to the preamplifier 31 . The signal amplified by this preamplifier 31 is converted into a digital signal by an A/D conversion circuit 32 and supplied to a signal processing circuit 33. This signal processing circuit 33 calculates a deviation signal of the thickness of the center part of the board to be measured from the output of the A-D converter circuit 32 and the preset thickness of the center part of the board to be measured 91, and then performs D-A conversion. Supplied to circuit 34. Here, the same circuit 34 converts it into an analog signal again and supplies it to the profile calculation section soK. Since this profile calculation section 5.theta. receives a detection signal from the 11C5-in center detection switch 60, it calculates the center plate thickness from the output of the DA conversion circuit 34 based on this signal.

Next, the C frame truck 21 is moved by the profile measurement command signal FS from the outside, but at this time the next setting operation has already been performed.

That is, the speed change point set value E 81 is set in the speed change point setter 72, the measurement point set value low S is set in the measurement point setter 41, and the return value bar S is set in the return value setting device 91, respectively. Therefore, these settings%72.41.9
1, the set values E S, LOW S, and S are set, and when the profile measurement command signal FS is input as described above, the trolley control unit 80 outputs the forward command signal at the speed Vl shown in FIG. 9(a). is applied to the trolley drive motor 26. As a result,
As shown in FIG. 8, the C frame truck 21
Starting from L, it moves forward toward the plate end at a speed of V1. At this time, the up/down counter 71 has already been reset by the signal from the line center detection switch 60 and is ready for counting. Therefore, the counter 7 counts the output/4' pulse of the truck position detector 27 and outputs a position signal indicating how far the truck 2Z has moved from the line center CL. The comparison circuit 73 compares the position signal from the counter 71 and the speed change point setting value E S of the speed change point setter 72, and outputs a match signal when the trolley 21 reaches the speed change point A shown in FIG. Output.

Here, the trolley control unit 80 receives the coincidence signal and FIG. 9(a)
) is applied to the cart drive motor 26 to reduce the moving speed of the cart 21.

On the other hand, the field of view of the plate edge detector 25 is a range that covers the distance from the thickness measurement point 1j to the speed change point 1j as shown in FIG. 8-2.

For example, if the measurement point opening is 1511I+11 from the plate edge and the speed change point A is 50g1l from the plate edge, the field of view of the plate edge detector 25 is 10 in the direction perpendicular to the running direction C of the plate 91 to be measured.
It will be 0 songs. Therefore, the output of the plate edge detector 25 becomes zero near the center of the line as the light from the light source 23 is completely blocked, but since the plate edge detector 25 has the aforementioned detection field of view, the output of the bogie 2Z is By the time change point A is reached, detection output begins to appear. FIG. 9(C) shows this state.

The output of the plate edge detector 25 is constantly supplied to the comparison circuit 42. Therefore, the comparison circuit 42 compares the output of the plate edge detector 25 and the measurement point set value low S of the measurement point setter 41, and a coincidence signal is output when the trolley 21 reaches the measurement point opening. . When receiving a coincidence signal, the Zorophil calculation unit 50 calculates the edge thicknesses a and C shown in FIG. 1 from the output of the radiation measurement system 30, and stores and outputs the calculated values. however,
As will be described later, when the cart 2Z is turned back and the measurement point at the other end is detected, the profile calculating section 50 calculates and stores only the edge plate thickness a. Furthermore, as the trolley 21 moves forward, the output of the plate end detector 25 is turned back to the projector 9.
If it matches the return estimate value of I...-8, the comparator circuit 9
A coincidence signal is output from 2.

As a result, the truck control unit 80 gives a backward command signal of speed -vl to the truck drive motor 26 to cause the truck 21 to move backward. Then, using the same means as described above, the profile calculating section 50 calculates the edge portion plate thickness C shown in FIG. 1 on the other end side of the object to be measured 91 and stores and outputs it. Here, when the cart 21 moves back and forth once around the line center CL and the measurement is completed,
The truck control unit 80 stops the truck 21 at the line center CL. -10,000, the Zorophil calculation unit 50 stores the stored values a, b, c.
Crown lid using.

Calculates and outputs the wet amount, etc.

In the method shown above in which the plate edge of the object to be measured 91 is detected by the plate edge detector 25 and the trolley 21 is controlled, the object to be measured 91 is always within the radiation beam, so it is difficult to detect the object 91 off the edge of the plate. There is no delay in response. Also, after detecting the measurement point,
Since the thickness of the edge portion is determined from the output of the radiation measurement system, the thickness is accurate and is not affected by the effects of lateral vibration of the plate 91 to be measured. Although omitted in this example,
The flow calculation is performed using the difference between the output of the fixed thickness gauge installed at the center of the line CL and the output of the thickness gauge of this embodiment 911. Therefore, although not shown, it goes without saying that the output of the fixed thickness gauge is required as an input to the profile calculation section 50.

Note that the present invention is not limited to the above embodiments.

For example, a second and a third speed change point are provided between the speed change point A and the turning point -, and the speed of the cart at the turning point C is sufficiently reduced so that the cart 21 does not go over the edge of the plate. can do. Further, in this apparatus, the portions that can be processed by software can be implemented using a computer. Furthermore, if the light from the light source 23 is reflected by a mirror or the like and guided to the plate edge detector 25, the concave plate edge detector 25 can be installed at a position where it is not affected by radiation. Furthermore, since the distance between the plate edges is known, the thickness of the object 91 near the plate edge can be measured by following changes in the plate edge. In addition, the present invention can be implemented with various modifications without departing from the gist thereof.

Effects of the Invention As described in detail above, according to the present invention, the center of the line is detected and the temporary truck position signal is measured, so the position of the truck can be accurately known. In addition, since a speed change point set value is provided and the trolley is decelerated by comparing this set value with the position signal, it is easy to detect the measuring point of the trolley and prevent the trolley from overshooting at the edge of the plate. I can do it. In addition, the measurement points and turning points are obtained based on the pressure comparison results between the output of the sheet edge detector, each measuring point setter, and the output of the turning device. It can be measured without
Also, it can provide a radiation thickness measurement that allows profile measurement without being affected by the lateral vibration of the object to be measured.

[Brief explanation of drawings]

Figures 1 to 5 are diagrams explaining the conventional radiation thickness system, in which Figure 1 is a diagram showing the cross-sectional shape of a rolling plow plate, Figure 2 is a configuration diagram of the mechanical system, and Figure 3 is a signal diagram. Processing system configuration diagram,
Figures 4 (=) to (C) and Figure 5 are diagrams explaining the problems of the conventional radiation thickness set, Figures 6 to 9 (a) to
(c) is a diagram for explaining one embodiment of radiation thickness analysis according to the present invention, in which FIG. 6 is a configuration diagram of a mechanical system, FIG. 7 is a configuration diagram of a signal processing system, and FIG. Figures 9(a) to 9(c) showing each detection point of the object to be measured are operational characteristic diagrams. 21... Trolley, 22... Radiation, 23... Light source,
24... Radiation detector, 25... Board edge detector, 26
... Bogie drive motor, 27... Bogie position detector,
30... Radiation measurement system, 33... Signal processing circuit, 4
0...Measuring point detector, 4I...Measuring point setter, 42
... Comparison circuit, 50 ... Profile calculation section, 60.
...Line center detection switch, 70... Speed change detection section, 71... Counter, 72... Speed change point detection section, 80... Bogie control section, 90... Turning point detection section,
9I...Folded Megumi projector. Applicant's agent Patent attorney Takehiko Suzue Figure 1 Figure 2]a Figure 3・□

Claims (2)

[Claims] (1) In a radiation thickness meter that measures the profile of an object by moving a cart equipped with a radiation detection system, a signal that is preset to be 911 compared to the radiation obtained by passing through the object. a radiation measurement system for determining the deviation from a plate thickness signal of the object to be measured, a line center detection means for detecting the center of the line, and an output of a cart position detector installed on the cart, which is detected by the line center detection means. a speed change detection unit that measures the position signal of the trolley based on the signal and obtains a speed change point of the object to be measured using the second position;
A means for reducing the speed of the cart based on the output of the speed change detection section and a plate edge detector are provided on the cart, and the esso portion & Based on the measurement point detection section that obtains the thickness measurement timing, the detection signal obtained by the line center detection means, and the measurement timing of the edge portion plate thickness, the deviation signal output from the radiation measurement system is used to detect the object to be measured. A radiation thickness system characterized by comprising a profile calculation section that measures a profile. (2) In a radiation thickness meter that measures the profile of an object by moving a cart equipped with a radiation detection system, a signal proportional to the radiation dose obtained by passing through the object and a preset radiation a radiation measurement system for determining the deviation from a plate thickness signal of the object to be measured; a line center detection means for detecting the center of the line; and a signal detected by the line center detection means from the output of a cart position detector installed on the cart. a speed change detection section that measures the position of the cart based on the position signal and uses this position signal to obtain a speed change point of the object to be measured; and means for reducing the speed of the cart based on the output of the speed change detection section. and a measurement inspection peak part in which a plate edge detector is provided on the cart and the timing of measuring the plate thickness of one edge part of the object to be measured is obtained from the output of the detector and a preset measurement point setting value;
Detecting the turning point of the object to be measured from the output of the plate end detector and a preset cart turning black film constant value, moving the cart to the opposite plate end, and connecting the cart to the turning point detecting section; means for obtaining the measurement timing of the thickness of the other edge portion of the object to be measured using the output of the measurement point detector; and a means for obtaining the measurement timing of the thickness of the other edge portion of the object to be measured based on the detection signal obtained by the line center detection means and the measurement timing of the thickness of both edge portions. . A radiation thickness meter comprising: a profile calculation section that measures the profile of the object based on the deviation signal output from the radiation measurement system.