JPH0259520B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photoelectric conversion measurement device, in particular an on-line temperature pattern measuring device for a moving steel plate, which scans a moving object to be measured and measures light at a specific measurement position (sample position). The present invention relates to a photoelectric conversion measurement device that measures energy by photoelectric conversion.

For example, in a photoelectric conversion measurement device that measures the energy of light at a specific measurement position by scanning a moving object, such as an online temperature pattern measurement device for a moving steel plate, the pattern measurement accuracy is More importantly, it is necessary to always accurately position and measure a specific measurement position regardless of changes in the shape of the object to be measured or vertical displacement during movement.

For this reason, in conventional photoelectric conversion measurement devices of this kind, a mirror integration circuit is used to determine the specific measurement position, for example, and the specific measurement position is determined based on the integral value of the rectangular wave rising from the front end of the object to be measured. It was done like this. (For example, see "Measurement Technology 1974 Special Issue, pages 115 to 121"). In other words, in a method that determines a specific measurement position based on the integral value of this mirror integral, for example, in order to measure a specific measurement point that is a predetermined distance away from the front end of the object to be measured, the integral value rising from the front end is determined at that point. In order to perform a measurement when the integral value corresponding to the position of Therefore, the specific measurement point is determined and measured by referring to the integral value from the previous scan.

However, in the conventional method of determining the position using the integral value as described above, when the object to be measured is in a stationary state or meandering state, unless an error occurs in the integral value, the front and rear ends of the object are Even if it is possible to position a specific measurement position, for example, if the moving object to be measured is vertically displaced, or if the shape of the object itself changes, errors are likely to occur, especially after the It becomes impossible to accurately position a specific measurement position that is a predetermined distance away from the end, and therefore measurements must be made at a point that is deviated from the specific measurement position, making it impossible to obtain sufficient measurement accuracy. . In this case, especially when the amount of displacement such as the width of the object to be measured is large, the measurement must be performed at a point far away from the specific measurement position, and in some cases even outside the steel plate, which has the disadvantage of causing a large measurement error. It is.

Therefore, in conventional photoelectric conversion measuring devices such as online temperature pattern measuring devices for moving steel plates, the measurement positions are set at positions 20 to 50 mm away from each end of the steel plate, for example, in order to prevent them from deviating from the steel plate. Specific measurement positions are selected at each end, and the temperature pattern is measured at these specific measurement positions. In this way, by selecting the specific measurement position at a position considerably distant from each end, even if the measurement position changes by, for example, ±10 mm, the measurement point will not come off the steel plate. However, although such conventional online temperature pattern measuring instruments can be applied as a simple method when measuring the rough temperature distribution of each part of a steel plate that is being heated as a whole, for example, This method cannot be applied to methods that require accurate temperature distribution measurement at each part, such as measurement of temperature distribution in a method of manufacturing pipes in which pipes are continuously processed from plate materials. This is because in the manufacturing method of this type of pipe, only the joint ends require high temperature for welding, and heating the entire plate material is inefficient and wastes energy, so the current method In the pipe manufacturing method, an edge heater is used to heat only the ends to be welded to perform local heating, and parts other than the ends are heated at a low temperature in order to save energy. The purpose of the online temperature pattern measuring device used in this pipe manufacturing method is completely different from the conventional method of measuring the temperature pattern of the entire board, and in particular, it is necessary to measure the temperature pattern at a specific measurement point at each end of the board, for example, just 5 mm from each end. It is necessary to accurately grasp the temperature at a specific measurement location that is far away. Therefore, for this purpose, if the specific measurement position is set, for example, at a position 5 mm from each end in the conventional device, the width of the board is ±10 mm even if the width of the plate is constant.
Due to positional fluctuations in mm, the measurement point often deviates from the plate material, and as a result, the temperature, especially at the rear end, cannot be sufficiently determined, resulting in poor reliability. In addition, as mentioned above, the conventional method of determining a specific measurement position using an integral value cannot accurately determine the position when the measurement point changes due to vertical movement of the plate or change in the width of the plate. There is also the disadvantage that more reliable measurement values cannot be obtained since the method cannot be performed accurately. Furthermore, there is also the drawback that the integral value itself is susceptible to errors due to changes in ambient temperature.

The present invention was made in view of the above circumstances, and
The purpose of this is to scan the moving object to measure its width and relative position, refer to these values, measure at multiple measurement positions, and calculate the value at the optimal position as the measured value. By determining this as The purpose of the present invention is to provide a photoelectric conversion measurement device.

According to the present invention, the present invention includes: a signal detection section that scans a moving object to be measured and detects a signal; and a position detection section that detects the relative position of a corresponding signal corresponding to the object to be measured of an output signal of the signal detection section. , a sample hold unit that samples and holds detection signals at at least two positions according to the corresponding signal width of the previous scan detected by the position detection unit and the front end signal of the corresponding signal of the current scan; and the sample hold unit. a converting section that converts the output of the converting section; a storage section that stores the output of the position detecting section and the output of the converting section, respectively; A photoelectric conversion measurement device is obtained, comprising: a control section that determines one of the two outputs as a measurement value for the current scan;

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a block diagram showing the overall configuration of a photoelectric conversion measurement device according to the present invention, which includes a signal detection section 2 that scans a moving object 1 to detect signals; The signal detection section 2
and a signal processing section 3 that processes the output signals of.

FIG. 2 shows the output waveforms of the circuits included therein.

The signal detection section 2 includes a photoelectric element 4, an optical system 5 that converges the light from the wave measurement object 1 onto the photoelectric element 4, and performs rotation scanning by a synchronous motor (not shown).
It consists of an amplifier 6 that amplifies the output of the photoelectric element 4. The output waveform of the photoelectric element 4 is 1 in FIG.
The waveform is as shown in 01.

Furthermore, a synchronization signal 108 is generated in response to rotational scanning of the objective lens.

The processing section 3 further includes a correction section, a position detection section, a sample hold section, a conversion section, a storage section, and a control section.

The correction section is provided mainly for the purpose of correctly measuring the radiation temperature, and is composed of a distance correction circuit 7, an emissivity correction circuit 8, and a linearization circuit 9, and the output of the amplifier 6 of the signal detection section 2 is The signal is input to a correction circuit 7.

The distance correction circuit 7 is composed of an amplifier circuit and the like that performs correction such as applying a bias voltage according to the square of the installation distance between the photoelectric element 4 of the signal detection section 2 and the object to be measured 1.

The output of the distance correction circuit 7 is input to the emissivity correction circuit 8, and in order to measure the true temperature, the output of the distance correction circuit 7 is corrected by applying a bias to compensate for the decrease in emissivity due to surface roughness, etc. It is configured with an amplifier circuit and the like, and outputs to the linearization circuit 9.

Furthermore, the linearization circuit 9 is composed of a nonlinear amplifier circuit, etc. that linearly corrects the relationship between the detection signal and the surface temperature, and its output is connected to one end of the sample and hold circuit 10 and the comparison circuit 11, respectively. The output waveform is as shown at 102 in FIG.

The position detection section further includes a comparison circuit 11, a clock circuit 12, an arc correction circuit 13, and an AND circuit 1.
4. NOT circuit 15, R-SFF circuit 16 and AND
It is composed of a circuit 17.

Among these, the output of the linearization circuit 9 is input to one terminal of the comparison circuit 17, and the reference voltage Vref having a value determined by referring to the previous scan is input to the other terminal. Therefore, the output signal becomes a rectangular wave as shown at 103 in FIG. 2, and each of these rectangular waves is connected to one terminal of the AND circuit 14
It is configured to be input to the NOT circuit 15.

Further, the clock circuit 12 generates a second wave having a higher frequency than the rectangular wave created by the comparison circuit 17.
A clock pulse as shown at 104 in the figure is generated and its output is input to the arc correction circuit 13.

Furthermore, the arc correction circuit 13 is mainly composed of a frequency conversion circuit that changes the pulse interval of clock pulses, and is configured to detect the number of pulses and the distance above the object 1, which is generated by detecting a signal by arc scanning a flat object 1, for example. It is designed to correct the error in the ratio between

The output signal of the arc correction circuit 13 is a signal shown at 105 in FIG. 2, and these signals are input to the other end of the AND circuit 14 and one terminal of the AND circuit 17, respectively.

Furthermore, the AND circuit 14 ANDs the output of the comparator circuit 11 and the output of the arc correction circuit 13,
The output signal becomes a signal as shown at 106 in FIG. 2, and this signal is input to the counting circuit 18.

Since the counting circuit 18 counts the output pulses of the AND circuit 14, the counted value corresponds to the length of the object 1 in the scanning direction.

The output of the comparison circuit 11 is inverted by the NOT circuit 15 as shown at 107 in FIG. 2, and is input to the reset terminal R of the R-S flip-flop circuit 16. synchronous signal generation circuit 19 of device 2
The synchronizing signal 108 shown in FIG. 2 generated in the above is inputted.

Furthermore, the output of the flip-flop circuit 16 is inputted to the other end of an AND circuit 17, which has one terminal inputted with the output of the arc correction circuit, and the output signal of the flip-flop circuit 16 is as shown in FIG. The waveform is as shown in 109 of FIG.

Further, the output of the AND circuit 17 is output from the counting circuit 20.
The output signal is as shown at 110 in FIG.

Therefore, the value counted by the counting circuit 20 is:
It shows the pulse value from the synchronization signal to the front end of the object to be measured 1.

The output of the synchronizing signal generating circuit 19 of the signal detecting section 2 is input to the counting circuit 18 and the counting circuit 20, respectively, and each is reset by the synchronizing signal 108 shown in FIG. .

Furthermore, each output of the counting circuit 18, the counting circuit 20, the synchronizing signal generating circuit 19, and the sample position setting circuit 21 for setting the lateral fixed position on the object 1 to be measured as, for example, 50 mm from the rear end as a digital signal is sent to the control circuit 22. It is designed to be entered in Here, the sample position setting circuit 21 converts the measured position into a digital signal, for example, as a distance from the rear end, and transmits the digital signal to the control circuit 21.

Further, the conversion section described above includes the sample and hold circuit 1
0 (hereinafter referred to as S/H circuit), analog-digital conversion circuit 24 (hereinafter referred to as A/D conversion circuit),
It is composed of a conversion calculation circuit 25.

Among these, the S/H circuit 10 performs sample and hold using a sample and hold signal 23 from a control circuit 22, and its output is input to an A/D conversion circuit 24.

Further, the A/D conversion circuit 24 converts the output of the S/H circuit 10 into digital data, and the digitally converted output is inputted to the conversion calculation circuit 25.

Furthermore, the conversion calculation circuit 25 converts the output value of the A/D conversion circuit 24 into the unit for the purpose of measurement,
The converted output is input to the control circuit 22.

The storage device 26 stores the respective outputs of the conversion calculation circuit 25, the counting circuit 18, and the counting circuit 20, which are input to the control circuit 22, and is connected to the control circuit 22 as shown in the figure.

Furthermore, a CRT display 27 is provided to display the output of the control circuit 22.

Next, the operation of the embodiment of the present invention constructed as described above will be explained. For convenience of explanation, the explanation will be based on FIG. 3 showing a flowchart of the embodiment of the present invention shown in FIG. 1, and an explanatory diagram shown in FIG. 4 for explaining the setting of the sample position in the embodiment.

In FIGS. 3 and 4, the measurement operation is first started by the synchronization signal a from the synchronization signal generation circuit 19, and the distance A from the scanning start point to the front end of the object to be measured 1 is measured by the position detection unit in the first scan. The output of the AND circuit 17 is measured as the count value of the counting circuit 20. Next, a preset sample position G ₀ of the object 1 to be measured is sampled, and the width value L ₀ of the object 1 to be measured is measured. Assume that during the next scan, as shown in FIGS. 4c to 4f, the plate width value relatively fluctuates due to changes in shape, vertical displacement, etc. as the object 1 moves as shown in FIGS. 4c to 4f.

Therefore, by this scanning, the distance B from the scanning start point to the front end of the object to be measured 1 is measured again as the count value of the counting circuit 20. Next, the control circuit 22 calculates the difference (AB) between the distances A and B to the front end obtained by the position detection section. Then L′ ₁ =L ₀ +2
Sample and hold circuit 1 performs calculation of (A-B)
A sample hold signal 23 is sent to 0 to perform sampling at _two sample positions G ₁ and G . Next, the actual measurement value L _{1 of the width value of the object to be measured 1} is measured as the count value of the counting circuit 18, and this L ₁ and L ₁ ' are sent to the control circuit 22.
It is determined whether the following conditions are satisfied: L ₁ =L ₀ =x ₀ |x ₀ |≦a (a is a set value) (1).

When formula (1) is satisfied _{, the} following condition is satisfied: L ₁ −L ₁ ′=x ₁ | −|x ₁ |≦0 (3) If the following is satisfied, the sampled value at point _G1 is determined as the measured value and displayed on the CRT display 27. As a result, if the scan continues, the measurement returns to the first measurement of A, and if the scan ends, the measurement operation ends.

If L ₁ and L ₁ ′ are compared, equation (1) is satisfied, but (2)
If the formula is not satisfied, the sampled value at point _G1 is determined as the measured value in the same manner as above, and the operation is displayed as described above.

Also, compare L ₁ and L ₁ ', and if equations (1) and (2) are satisfied but equation (3) is not satisfied, the sampled value at the _two points G is determined as the measured value and the above The operation is displayed as follows.

Furthermore, when comparing L ₁ and L ₁ ′, if equation (1) is not satisfied but equation (2) is satisfied, the sampling value at point G ₂ is determined as the measured value and the operation is displayed in the same way as above. Furthermore, if neither equation (1) nor equation (2) is satisfied, the sampled value at point _G0 is determined as the measured value and is displayed on the CRT display 27 in the same manner as described above.

According to the present invention, the above-mentioned operation is repeated until the end of the scan, so that the width of the object to be measured is always maintained regardless of changes in the shape of the moving object or displacement in the vertical direction during movement. It is possible to accurately measure the position and relative position thereof, refer to that value, measure at multiple measurement positions, and determine the value at the optimum position among them as the measurement value, thereby reducing errors in the measurement position. For example, the temperature at each end of a moving object can be measured more accurately, and a highly reliable online temperature pattern can be obtained.

Although one embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to what has been shown in the above embodiment, and that various modifications and changes can be made. For example, the signal detection section in the above embodiment,
Of course, any other signal processing circuits that operate in the same manner as these circuits may be used as the position detection section, control section, etc. included in the signal processing section. Further, in the above embodiments, the present invention was described as being applied to the measurement of temperature patterns, but it is clear that it can also be applied to pattern measurements other than temperature, such as color pattern measurements, etc., as long as light energy is photoelectrically converted and measured. .

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the overall configuration of an embodiment of the present invention, FIG. 2 is a waveform diagram showing output waveforms of each circuit in FIG. 1, and FIG. A flowchart diagram for explaining the operation of the embodiment, and FIGS. 4a to 4f are explanatory diagrams for explaining the setting of the sample position in the embodiment of the present invention shown in FIG. 1. DESCRIPTION OF SYMBOLS 1...Object to be measured, 2...Signal detection section, 3...Signal processing section, 4...Photoelectric element, 5...Optical system, 6...
...Amplifier, 7...Distance correction circuit, 8...Emissivity correction circuit, 9...Linearization circuit, 10...Sample hold circuit, 11...Comparison circuit, 12...Clock circuit, 13...Circular arc Correction circuit, 14...AND
Circuit, 15...NOT circuit, 16...R-SFF circuit, 17...AND circuit, 18...Counting circuit, 1
9...Synchronization signal generation circuit, 20...Counting circuit, 2
1... Sample position setting circuit, 22... Control circuit, 23... Sample hold signal, 24...
A/D conversion circuit, 25... Conversion calculation circuit, 26...
...Storage device, 27...CRT display.

Claims (1)

[Scope of Claims] 1. A signal detection unit that scans a moving object to be measured and detects a signal; and a position detection unit that detects the relative position of a corresponding signal corresponding to the object to be measured of an output signal of the signal detection unit. a sample hold unit that samples and holds detection signals at at least two positions according to the corresponding signal width of the previous scan detected by the position detection unit and the front end signal of the corresponding signal of the current scan; a conversion unit that converts the output of the hold unit; a storage unit that stores the output of the position detection unit and the output of the conversion unit, respectively; A photoelectric conversion measurement device comprising: a control section that determines any one of at least two outputs as a measurement value for the current scan. 2. In the device described in claim 1, the control unit converts the output of the conversion unit or the previous scan stored in the storage unit according to the corresponding signal of the previous scan and the corresponding signal of the current scan. The photoelectric conversion measuring device according to claim 1, wherein any one of the values determined as the measurement value is determined as the measurement value of the current scan.