JPH0543048B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a scanning radiation thermometer that measures the temperature at each position of a measurement target.

[Prior Art] When measuring the temperature distribution in the width direction of a moving steel plate or the like using a scanning radiation temperature sensor, the steel plate may fly up and down, shift left or right, or meander.

[Problems to be Solved by the Invention] As described above, when a steel plate meanderes, the scanning width of the scanning radiation thermometer is constant, so when measuring, the apparent size of the width of the steel plate, the left and right sides, etc. Misaligned,
For example, the peak temperature position will also fluctuate from side to side. When recording this peak temperature position with an analog recorder, even if the peak temperature position on the steel plate does not change, the recording result moves due to the movement of the steel plate, making it impossible to obtain the correct peak temperature position record. The dot was hot.

In view of the above points, an object of the present invention is to provide a scanning radiation thermometer that can obtain positional information without being affected by meandering of a measurement object such as a steel plate.

[Means for Solving the Problems] The present invention includes a detection section that scans a measurement target and detects radiant energy at each position, and a detection signal of this detection section and a predetermined threshold value that are compared with each other. In scanning, the width value of the measurement target is determined from the difference between the first position at which the threshold value or higher and the second position at which the threshold value is or higher. The scanning radiation thermometer is equipped with an arithmetic unit that performs scaling conversion of a position based on a width value.

[Example] Fig. 1 is an explanatory diagram of a measurement state showing an embodiment of the present invention, Fig. 2 is a signal waveform diagram, and Fig. 3 is an explanatory diagram of the configuration.

In FIG. 1, a detecting section 2 scans the width direction of a measuring object 1 such as a traveling steel plate with a predetermined scanning width _W0 , detects radiant energy at each position, and supplies it to a calculating section 3. The detection section 2 and calculation section 3 constitute a scanning radiation thermometer.

As shown in FIG. 3, the radiant energy from the measurement object 1 is focused by an optical system such as a lens 21, and is incident on a detection element such as an image sensor 22, and is detected at each position of the measurement object 1. Radiant energy is converted into an electrical signal. The detection signals of each element of the image sensor 22 are sequentially read out by the drive pulse of the drive circuit 23, and are amplified by the amplifier 24.
The signal is supplied to the A-D converter 31 of the calculation unit 3 together with the drive pulse (pixel corresponding clock) of the drive circuit 3 indicating the position signal, and is converted into a digital signal.
It is stored in RAM32. Arithmetic unit 3 is ROM33
The following calculations are performed by this processing means 34, and the peak temperature, peak temperature position signal, etc.
It is converted into an analog signal by the A converter 35 and outputted via sample and hold circuits 36, 37, and 38.

The output, which is a brightness signal of the image sensor 22 and stored in the RAM 32, is converted into a temperature signal by the processing means 34.

Next, as shown in Fig. 2, an appropriate predetermined threshold value To is compared with the detection signal at each position in the scan, which can be known from the pixel corresponding clock, and the detection signal is Threshold To
A first position (pixel number) N1 that is above the threshold value To, a second position (pixel number) N2 that is below the threshold value To, and a third position that corresponds to the peak temperature Tp above the threshold value To.
Find the position (pixel number) Np. Then, from the difference between the first and second positions N1 and N2 indicating the end position, the width value W of the measurement object 1 is determined, and the third position Np and the first position are determined.
The peak temperature position L is determined from the difference from N1 using the following formula.

W=A・(N2−N1) ……(1) L=A・(Np−N1) ……(2) From this, using the width value W as the reference (100%), calculate the scaling conversion of the peak temperature position L. Calculate the scaling value Lp using the following formula.

Lp = (L/W) x 100 (%) ...(3) This scaled position signal Lp is not affected by the meandering etc. of the measurement object 1 and is based on the width value of the measurement object 1 itself. .

Therefore, when outputting to an analog recorder or the like for recording, the effective recording width of the recording paper always corresponds to the plate width, and the position can be directly read from the recording paper.

In addition, in equations (1) and (2), A is the measurement distance and lens 2
It is a coefficient determined by the focal length of 1, the size of 1 pixel of the image sensor 22, etc., and its unit is mm/1 pixel.

Alternatively, the width of the measurement object 1 may be divided, and the peak temperature value in each divided region and the position corresponding to this peak temperature may be converted into scaling and output.

Alternatively, the detection section 2 may be one that scans the measurement target using a rotating mirror and one detection element and measures the radiant energy at each position, without using an image sensor.

[Effects of the Invention] Since the present invention scales the position using the width value as a reference, it is possible to always obtain temperature signals and position signals based on the width of the measurement object, thereby eliminating the influence of meandering of the measurement object, etc. Accurate measurements can be taken without any interference.
When this scaled position signal is recorded on an analog recorder, the width of the recording paper always becomes the width of the object to be measured, making it easy to read the position directly.

[Brief explanation of the drawing]

FIG. 1, FIG. 2, and FIG. 3 are explanatory diagrams showing one embodiment of the present invention. 1... Measurement object, 2... Detection section, 3... Calculation section.

Claims (1)

[Claims] 1. A detection unit that scans the measurement target and detects radiant energy at each position, and compares the detection signal of this detection unit with a predetermined threshold, and in one scan, detects the radiation energy at each position. The width value of the measurement target is determined from the difference between the first position where the temperature is equal to or lower than the threshold value, and the third position corresponding to the peak temperature at the threshold value or higher is determined. A scanning type equipped with an arithmetic unit that calculates the scaled peak temperature position by dividing the position based on the width value, and a sample hold circuit that outputs the peak temperature signal and peak temperature position signal obtained by this arithmetic unit. Radiation thermometer. 2. Claim 1, in which the width of the measurement object is divided, and the peak temperature in each divided area and the peak temperature position after scaling are determined and output.
Scanning radiation thermometer described in Section 1.