JP2932862B2 - Method and apparatus for measuring cross-sectional shape of plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for measuring a sectional shape of a plate-like body such as a steel plate.

[0002]

2. Description of the Related Art An ultra-thin metal strip is obtained by cold rolling a hot-rolled coil and winding it around a coil. Even when the coil is wound, the change in the thickness of the coil in the width direction increases as the number of turns of the coil increases. Further, when winding the metal band around the coil, the metal band is wound with tension applied thereto, and a compression force is applied in the thickness direction of the metal band due to tight tightening. Here, if there is a thickness change in the width direction of the metal band, the compressive force concentrates on the thick part,
The material changes at the position in the width direction of the metal band where the compressive force is concentrated. For this reason, it is necessary to suppress the thickness change of the ultrathin metal band in the width direction to 5 μm or less. In order to inspect the thickness change of 5 μm or less, the width of the metal band is measured with a measurement accuracy of 1 μm or less. The thickness distribution in the direction must be measured.

[0003] Japanese Patent Application Laid-Open Nos. 56-72308 and 57-1 describe methods for measuring the thickness of a metal strip in the width direction.
There is a technique described in Japanese Patent Publication No. 19205. FIG. 9 is an explanatory diagram of the former contents, and FIG. 10 is an explanatory diagram of the contents of the latter.

In FIG. 9, upper and lower laser beam emitting devices 71 and 72 are provided at appropriate positions on a strip 74 traveling in a predetermined direction on a guide roll 63, and receive a laser beam emitted from a strip detection point. Comprising upper and lower laser beam detectors 67, 70 arranged,
The distance from the lower laser beam emitting apparatus 72 to the strip 74 t1, the thickness of the strip 74 t2, the upper rail
The distance from the beam emitting device 71 to the strip 74
Assuming that t3 is the distance between the upper laser beam emitting device 71 and the lower laser beam emitting device 72 and t is the speed of the laser beam, the strip thickness t2 is obtained from the following equation. t2 = t4-(t1 + t3) t1 = s x (T3 + T4) / 2 t3 = s x (T1 + T2) / 2, where T1 is the optical axis distance from the upper laser beam emitting device to the strip. T2 is from the upper laser beam detector. T3: Optical axis distance from the lower laser beam emitting device to the strip T4: Optical axis distance from the lower laser beam detector to the strip

In FIG. 10, a light source 83 is arranged on one side in the width direction of the steel plate 82, and an image pickup device 84 is arranged on the other side.
The boundary between the light receiving portion 3 and the light shielding portion of the steel plate 82 is detected, and one of the upper surface and the lower surface of the steel plate 82 is specified to measure the thickness of the steel plate 82.

[0006]

However, in the shape measurement according to JP-A-56-72308, the distance is determined from the speed of the laser beam, and the strip thickness is measured from this distance. A suitable time measurement resolution is needed, which is 1 /
It is almost impossible with a resolution of (3 × 10 ¹¹ ) seconds. According to the shape measurement according to Japanese Patent Application Laid-Open No. 57-119205, the boundary between the light receiving portion and the light shielding portion of the light of the light source detected by the imaging device is a projection of the thickness distribution in the width direction of the steel plate. Therefore, it is difficult to accurately measure the cross-sectional shape. In addition, both of them are intended for online measurement, and it is not possible to measure the thickness distribution in the width direction with high accuracy and fineness, and to determine the cross-sectional shape thereof. The present invention has been made to solve these problems.

[0007]

According to the method of the present invention, the first and second laser displacement meters are opposed to each other with a plate-like body to be measured placed on a surface plate interposed therebetween. The laser displacement meter fixes the lower surface of the plate-like body at a position substantially at the center of its measurement range, and the second laser displacement meter is configured to be movable in the facing direction, and the lower surface position of the plate-like body is The two laser displacement meters are calibrated as a reference, and the second laser displacement meter is preset at a position where the upper surface of the plate-like body is substantially at the center of the measurement range to obtain the preset amount L. The laser displacement gauge is slid in the width direction of the plate while holding the laser displacement meter at this interval, and the displacement to the plate is measured by each displacement meter while pressing the plate against the surface plate, and the second measurement is performed. Indicate the value when calibrating the laser displacement meter a ₀ and the displacement measurement values during the sliding of the second laser displacement meter and La, La ₀ and the first indicated value when calibration of the first laser displacement meter
The displacement value at the time of the sliding of the laser displacement meter of the above is defined as Lb, and the thickness t of the plate-like body is obtained from t = L + (La−La ₀ ) − (Lb−Lb ₀ ) to calculate the sectional shape thereof. It is. Further, the apparatus of the present invention has a platen on which a plate-like body to be measured is placed and fixed, a frame sliding in the width direction of the plate-like body fixed to the platen, and fixed to the platen. A first laser displacement meter fixed to the frame such that the lower surface of the plate-like body is substantially at the center of the measurement range, and is opposed to the first laser displacement meter and movably mounted in the facing direction and attached to the frame. A second laser displacement meter, a calibrating means installed on the surface plate for calibrating the first and second laser displacement meters, A preset amount measuring means for presetting to a position substantially at the center of the measurement range to obtain the preset amount, and the plate-like member of the first and second laser displacement meters for pressing the plate-like member against the platen. Placed around the body measurement position From the corrected pressing roller, the calibration value and the displacement measurement value of the first laser displacement meter, the calibration value and the displacement measurement value of the second laser displacement meter, and the preset amount obtained by the preset amount measuring means. Calculating means for calculating the thickness of the plate-like body and calculating its cross-sectional shape.

[0008]

According to the method of the present invention, the thickness change in the width direction of the plate is obtained by adding or subtracting the amount of change in the thickness of the plate obtained by sliding the opposed laser displacement meter to the amount of movement of the laser displacement meter by the preset. That is, the cross-sectional shape of the plate is obtained. In the apparatus of the present invention, the preset amount of the second laser displacement meter is measured by the preset amount measuring means, and the first laser displacement meter and the second laser displacement meter are slid by the frame to change the thickness of the plate-like body. The amount is measured over the width of the plate,
The thickness in the width direction of the plate-like body, that is, the cross-sectional shape of the plate-like body is obtained from the preset amount and the thickness change amount in the calculating means.

[0009]

1 is a front view showing a measuring apparatus according to an embodiment of the present invention, FIG. 2 is a side view thereof, and FIG. 3 is a plan view thereof.
In the figure, 1 is a thin plate as an object to be measured, 2 is a platen on which the thin plate 1 is placed, 3a, 3b, and 3c are electromagnets for fixing the thin plate 1 provided on the platen 2, and 4 is an opening of the platen 2. And 5, a C-shaped frame in which a portion corresponding to the upper surface of the surface plate 2 is formed with a concave portion, 6a
Is an opening 4 of the surface plate 2 below the concave portion of the C-shaped frame 5.
A first laser displacement meter fixed in accordance with the position of
Reference numeral 6b denotes a second laser displacement meter which is mounted on the upper side of the concave portion of the C-shaped frame 5 so as to be vertically movable (finely moved) by the moving mechanism 9 so as to face the first laser displacement meter 6a. The first laser displacement meter 6a and the second laser displacement meter 6b use a high-resolution minute displacement meter with a measuring range of 1600 μm and a resolution of 0.1 μm, and the stopping accuracy of the moving mechanism 9 is about ± 2 μm. In addition, the first laser displacement meter 6a
Is arranged so that the center of the measurement range is substantially at the upper surface of the surface plate 2. Therefore, if the object to be measured is placed in close contact with
The lower surface is substantially at the center of the measurement range of the first laser displacement meter 6a.

[0010] 10a, 10b the C-type frame 5 on the surface plate 2
, A ball screw for sliding the C-type frame 5, 12 a driving source for rotating the ball screw 11, 13 a position detector of the C-type frame 5, 14 a and 14 b A block gauge installed on the upper surface of the surface plate 2 for zero point calibration of the first laser displacement meter 6a and the second laser displacement meter 6b.
It is a guide for positioning of the. 17a-17b, 18
Reference numerals a-18b denote position detectors of the light emitting and receiving method attached to the rails 10a and 10b for detecting the initial position and the movement limit position of the C-shaped frame 5, respectively, and 19 denotes the position detector 1
A light-shielding plate provided on the frame 5 for shielding the optical paths of 7a-17b and 18a-18b, and 20a and 20b are a first laser displacement meter 6a and a second laser displacement meter for detecting the end of the thin plate 1, respectively. The thin plate detectors 21a, 21b, 21c and 21d provided on the thin plate 1 are provided by a first laser displacement meter 6a and a second laser displacement meter 6b.
Is a pressing roller arranged around the measuring section of the thin plate 1 in order to press the measuring section on the surface plate 2.

Next, measurement of the cross-sectional shape of the thin plate 1 by the present apparatus will be described. In the initial state, the C-shaped frame 5
Is located at a position where the light-shielding plate 19 shields the position detectors 17a-17b. First, the thin plate 1 is pressed against one end of the thin plate 1 with the guide 16 so that the tip of the thin plate 1 covers the opening 4 of the surface plate 2.
It is put in the concave portion of the mold frame 5 and placed on the surface plate 2. Here, when a measurement start switch (not shown) is turned on, the electromagnet 3
The thin plate 1 is suction-fixed to the surface plate 2 by the action of a, 3b and 3c.

Next, the ball screw 11 is rotated to slide the C-shaped frame 5 along the rails 10a and 10b. At this time, the second laser displacement meter 6b performs the zero point calibration at the measurement point at the position of the block gauge 14a,
The laser displacement meter 6a has a measurement point of a block gauge 14b.
Perform the zero point calibration at the position of. Further C type frame 5
Slide the first laser displacement meter 6a and the second
Laser displacement meter 6b from the end of the thin plate 1 50-100m
m. At this position, the second laser displacement meter 6b
Is finely moved upward by the moving mechanism 9 and set (preset) so that substantially the center of the measurement range becomes the upper surface of the thin plate 1. In this case, by using a pulse motor having a moving amount of 0.2 μm per pulse for the moving mechanism 9, the fine movement amount of the second laser displacement meter 6 b can be accurately calculated by counting the number of driving pulses of the pulse motor. Can be measured.

Note that the first laser displacement meter 6a and the second
In addition to the laser displacement meter 6b, a thickness measuring device may be provided to measure the thickness of the thin plate 1, and the measured value may be used to slightly move the second laser displacement meter 6b upward.
Further, the fine movement amount of the second laser displacement meter 6b may be measured not by counting the number of driving pulses of the pulse motor but by using a separately provided displacement meter. Further, these separately provided measuring instruments can be used for checking the mechanical accuracy.

Next, once the C-shaped frame 5 is slid to the left until the measurement points of the first laser displacement meter 6a and the second laser displacement meter 6b deviate from the thin plate 1, the C
Slide the mold frame 5 to the right, and
a and 20b detect the end of the thin plate 1 from a position where the measurement points of the first laser displacement meter 6a and the second laser displacement meter 6b come on the thin plate 1 at a predetermined interval, for example, 5 mm. The displacement is measured over the entire width of. FIG. 4 illustrates the operation of the laser displacement meter in this displacement measurement, in which the first laser displacement meter 6a indicates the distance displacement to the lower surface of the thin plate 1, and the second laser displacement meter 6b indicates the upper surface of the thin plate 1. The distance displacement to is shown.

If the plane shape of the first laser displacement meter 6a and the second laser displacement meter 6b at the measurement point of the thin plate 1 is not flat, the displacement measurement is performed at right angles to the thickness direction of the thin plate 1. Since the laser beam cannot be reflected in the same direction as the flat direction, a measurement error occurs. In this case, the second laser displacement meter 6b
Rollers 21a to 21d
The displacement can be measured at right angles to the thickness direction of the thin plate 1 by performing the measurement while correcting the planar shape of the measurement point.

Next, from the measured displacement of the first laser displacement meter 6a, the measured displacement of the second laser displacement meter 6b, and the amount of fine movement upward of the second laser displacement meter 6b,
A method for determining the thickness of the sheet will be described. As shown in FIG. 5, the amount of fine movement of the second laser displacement meter 6b (preset value obtained from the driving pulse count value of the pulse motor of the moving mechanism 9)
Is L, the indicated value at the time of zero point calibration of the second laser displacement meter 6b is La ₀ , the measured value of the displacement of the upper surface of the thin plate 1 is La, and the indicated value at the time of zero point calibration of the first laser displacement meter 6a is Lb. ₀ ,
When the measured value of the displacement of the lower surface of the thin plate 1 is Lb, the thickness t of the thin plate 1 is obtained by the following equation. t = L + ΔLa−ΔLb where ΔLa = La−La ₀ ΔLb = Lb−Lb ₀

FIG. 6 is a schematic block diagram of the present invention. The measurement mechanism 30 is operated from the operation display unit 50 to obtain each measured value, the measured value is processed by the arithmetic and control unit 40, and the result is displayed on the operation display unit. 50 is output. The operation display unit 50 is equipped with operation devices for starting measurement and confirming the operation of the measurement mechanism 30, and displays a measurement value of each displacement meter and a calculated cross-sectional shape measurement result.

FIG. 7 is an explanatory diagram of signal processing in the arithmetic control unit 40. The arithmetic control unit 40 includes input units 41a to 41
d, an arithmetic processing unit 42, and a sequence processing unit 43. The input unit 41a has a position detector 13 for a C-type frame.
, A measurement signal of the second laser displacement meter 6b at the input section 41b, a measurement signal of the first laser displacement meter 6a at the input section 41c, and a second measurement signal at the input section 41d.
A pulse count signal from the moving mechanism 9 when the laser displacement meter 6b is slightly moved is input. Further, the sequence processing unit 43 operates the measuring mechanism 30 according to a predetermined procedure, and gives the arithmetic processing unit 42 an instruction to take in a signal from the input units 41a to 41d. The arithmetic processing unit 42 shown in FIG.
In the sequence processing unit 43, the codes used for signal transmission / reception indicate the same symbols as those in FIGS. 1 to 3 and indicate that signal transmission / reception is performed with each of these devices.

FIG. 8 is a flowchart showing a measurement procedure by the apparatus of the present invention. According to this, first, the C-shaped frame 5 is slid to the position of the block gauges 14a and 14b, the first laser displacement meter 6a and the second laser displacement meter 6b are zero-point calibrated, and the measured values are respectively measured. The zero point of the displacement meter is set (S1 to S4). Further, after the C-shaped frame 5 is slid so that the second laser displacement meter 6b is located above the thin plate 1 (S5), the sequence processing section 4
3, the second laser displacement meter 6b is finely moved to make its measured value almost zero (S6), and the preset amount of the moving mechanism 9 required for this fine movement is sent to the input unit 41d and stored (S6).
7).

Next, the C-shaped frame 5 is once returned to the initial position (S8), and then slid in the direction of the thin plate 1 (S9). The thin plate detectors 20a and 20b detect the end of the thin plate 1 (S10), and the first laser displacement meter 6a and the second
The measurement point of the laser displacement meter 6b is positioned at this end (S11). From here, the C-shaped frame 5 is slid, and its displacement is measured at regular intervals over the entire width of the thin plate 1, that is, the width direction position of the thin plate 1 measured by the position detector 13 is input to the input unit 41a. The measurement value of the second laser displacement meter 6b is input to the input unit 41b, and the measurement value of the first laser displacement meter 6a is input to the input unit 41c. Further, these measured values are taken into the arithmetic processing unit 42, and the thickness of the thin plate 1 in the width direction is calculated (S12).

In this manner, the thin plate detectors 20a,
Up to the other end of the thin plate 1 detected at 20b.
The C-shaped frame 5 is slid so that the measurement positions of the laser displacement meter 6a and the second laser displacement meter 6b are located (S13, S14), and then the C-shaped frame 5 is returned to the initial position (S15). The arithmetic processing unit 42 calculates the cross-sectional shape of the thin plate 1 from the calculated thickness in the width direction and calculates the operation display unit 5.
The section shape of the thin plate 1 is displayed as 0 (S16).

Note that the measurement accuracy of the thickness of the object to be measured in the above embodiment depends on the measurement accuracy of the first laser displacement meter 6a and the second laser displacement meter 6b and the pulse count measurement accuracy from the moving mechanism 9. Determined, ± (0.1 ² +0.1 ² +0.2 ² ) ^1/2 = ± 0.24
μm, and the measurement accuracy of the thickness change amount of the object to be measured is ± (0.1 ² +0.1 ² ) ^1/2 = ± 0.14 μm, and high-accuracy cross-sectional shape measurement is possible. I understand.

[0023]

According to the method of the present invention, since the thickness change of the plate obtained by the laser displacement meter is used, the cross-sectional shape of the plate can be measured with high accuracy. According to the apparatus of the present invention, by providing a high-resolution laser displacement meter in a minute measurement range as the first laser displacement meter and the second laser displacement meter, the cross-sectional shape of the plate-like body can be measured with high accuracy. .

[Brief description of the drawings]

FIG. 1 is a front view showing a measuring device according to an embodiment of the present invention.

FIG. 2 is a side view of FIG.

FIG. 3 is a plan view of FIG. 1;

FIG. 4 is an explanatory diagram of an operation of a laser displacement meter which faces the object to be measured with the object interposed therebetween.

FIG. 5 is an explanatory diagram of a method of calculating a thickness of a measured object.

FIG. 6 is a schematic configuration diagram of the present invention.

FIG. 7 is an explanatory diagram of signal processing in an arithmetic control unit.

FIG. 8 is a flowchart showing a measurement procedure by the apparatus of the present invention.

FIG. 9 is an explanatory view of a conventional plate shape measurement.

FIG. 10 is an explanatory view of a conventional plate shape measurement.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Thin plate 2 Surface plate 3 Electromagnet 5 C-type frame 6a 1st laser displacement meter 6b 2nd laser displacement meter 9 Moving mechanism 11 Ball screw 21a-21d Holding roller

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Taku Ejiri 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Nippon Kokan Co., Ltd. (56) References JP-A-3-291505 (JP, A) JP-A-63 −106505 (JP, A) Japanese Utility Model Application Hei 4-59411 (JP, U) (58) Field surveyed (Int.Cl. ⁶ , DB name) G01B 11/00-11/30 102

Claims (2)

(57) [Claims] 1. A first and a second laser displacement meter are opposed to each other with a plate-like object to be measured placed on a surface plate interposed therebetween.
The first laser displacement meter has a lower surface of the plate-like body fixed at a position substantially at the center of its measurement range, and the second laser displacement meter is configured to be movable in a facing direction thereof. The two laser displacement meters are calibrated with reference to the lower surface position of the plate, and the second laser displacement meter is preset at a position where the upper surface of the plate-like body is substantially at the center of the measurement range to obtain the preset amount L. While holding the two laser displacement meters at this interval, slide in the width direction of the plate-like body, while pressing the plate-like body against the platen.
The displacement up to the plate-like body is measured by each displacement meter, and the indicated value at the time of calibration of the second laser displacement meter is La ₀ and the measured value of the displacement of the second laser displacement meter at the time of sliding is La. T = L + (La−La ₀ ) − (Lb−Lb, where La _{0 is} an instruction value at the time of calibration of the first laser displacement meter and Lb is a displacement value of the first laser displacement meter at the time of sliding. ₀ ), the thickness t of the plate-like body is obtained and the cross-sectional shape thereof is calculated. 2. A platen on which a plate-shaped object to be measured is placed and fixed; a frame sliding in the width direction of the plate-shaped member fixed to the platen; and a plate-shaped member fixed to the platen A first laser displacement meter fixed to the frame so that the lower surface of the first portion is substantially at the center of the measurement range, and a second laser displacement meter attached to the frame so as to be opposed to the first laser displacement meter and movable in the facing direction. A laser displacement meter, a calibrating means installed on the surface plate to calibrate the first and second laser displacement meters, and Preset amount measuring means for presetting to a position substantially at the center and obtaining the preset amount ; and the first and second means for pressing the plate-like body against the surface plate.
Around the measurement position of the plate-like body by the second laser displacement meter
From the placed holding roller and the calibration value and displacement measurement value of the first laser displacement meter, the calibration value and displacement measurement value of the second laser displacement meter, and the preset amount obtained by the preset amount measuring means. Calculating means for calculating the cross-sectional shape of the plate-like body by calculating the thickness of the plate-like body.