JPS58153103A - Device for detecting position and configuration of metallic material - Google Patents

Abstract

PURPOSE:To detect the position and the configuration without contact by a simple constitution, by detecting the displacement and the configuration of the matallic material by utilizing the relationship between the size occupied by the metallic material in an electric field and an electrostatic capacity. CONSTITUTION:The detecting device is constituted by a detecting end part 1, a shield case 2, electrodes 3 and 4, and an insulating material 5. The current, which is outputted from the electrode 4 and corresponds to the variation of the electrostatic capacity between the electrodes 3 and 4, is amplified by an amplifier 10. The AC output from the amplifier 10 is converted into a DC by a converter 11. An AC is supplied to the electrode 3 from an AC oscillator 13.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for detecting the position and shape of a metal material O using a static response quantity.

For example, in a processing line for IJ tubes, the amount of displacement in the width direction (meandering) of a running steel strip is detected and tracking control is performed, and in the manufacturing process of steel pipes, the roundness of steel pipes is detected. It is extremely important industrially to continuously measure the position and shape of metal materials in a non-contact manner, such as when feeding back information to the processing process.

Conventionally, for example, steel steel) 13-tube 4-y control (
In order to perform edge position control), a fluid flux such as an air flow is used as a means to detect the amount of widthwise displacement of the edge of the steel strip, and the receiving hole is There are some that use pressure changes in the air, and others that use light flux as a substitute for fluid flux.

However, conventional sensors that use flux bodies such as airflow (1) have a narrow measurement range of about ±5-500 mm at most (and cannot be applied to metal materials with large thickness dimensions). (3) Since fluid flux is used, for example, when measuring a steel strip,
If the strip is loose, it will cause turbulence and increase errors.

Ninth, for optical sensors that use luminous flux (1
) The price is high; (2) it is not possible to determine the III of high-temperature materials;
(To) It has the disadvantage that maintenance is difficult.

This invention eliminates these drawbacks in the prior art,
This method can be used for the purpose of obtaining a means for measuring the position and shape of a metal material, and its characteristic feature is that an electrode is provided, and an alternating current oscillator that supplies an alternating current to one of the electrodes is provided, and an alternating current is output from the other electrode. and an amplifier for amplifying a current corresponding to the large tooth size occupied by the metal material in a direction K) parallel to the electrodes between the electrode plates. The present invention will be explained in detail below.

This invention detects the displacement or shape of a metal material O by using the relationship between the size occupied by the metal material in an electric field and the capacitance OII. First, the present invention will be described with respect to a case where displacement in the width direction of the edge O of a metal material such as a metal strip lip is detected.

FIG. 1 shows an embodiment of this invention.

FIG. 1(b) shows a cross section at the muum 1sK of FIG. 1(a).

In these figures, reference numeral 1 denotes a detection end, which is composed of a shield case 2, an electrode 3.4, and an insulator 5.

10 amplifiers, electrode 3. output from electrode 4.
The current corresponding to the change in capacitance O between 4 and 4 is amplified. 11ij converter, which converts the AC (alternating current) output from the amplifier 10 into DC (direct current). 13 is an AC oscillator that supplies AC current to the electrode 3.

FIG. 2(a) K shows the relationship between the width direction position of the metal material 500 and the capacitance between the electrodes (5) and (@) in the system shown in FIGS. 1(a) and (b), that is,
If X is the length that the material 50 shields between the electrodes 3.4 in a direction parallel to the electrodes 5.4, then the capacitance C between the electrodes 3.4 is 4r when the metal is not grounded. Company, indicated by . 9. The capacitance when the material 50 is a grounded metal is expressed as (the current flowing from the upper electrode to the lower electrode is interrupted by the length X).

Here, 1; Thickness of the material ε; Dielectric constant of the metal material ε; Dielectric constant L of the electrode 5.4; Length d of the electrode; Distance of the electrode 3.4 - 1 charge. 2. The case where the material 50 is metal f will be explained. In this way, the displacement in the metal material 5QOQ direction can be understood as a capacitance change in metal #50 between electrodes 3.4 that is proportional to the length xK in the direction parallel to the electrodes. Even if the material SO is displaced vertically in the longitudinal direction of the electrode, for example, there is flapping in a steel strip, it will not be affected, and even if the metal material 5GO is thick, it will not affect the measurement accuracy. Normally, the metal material 50 can be supplied with an alternating current to one of the electrodes and detect the current change due to the capacitance change between the electrodes 3.4. Since it is electrically grounded through the frame base, it is completely unaffected by stray capacitance between the metal material 50 and the ground, and is also unaffected by temperature.

To explain the operation of the metal material position detection device according to the present invention shown in Fig. 1, when an alternating current is supplied from the AC oscillator 1S to the electrode 3, the metal material 5 is moved between the electrodes 3 and 4.
0 is the shielding length! A current proportional to is output from the electrode 4. The current output from the electrode 4 is amplified by an amplifier 10 and subjected to C/DC conversion by a converter 11.

The required current outputted from the converter 11 is inputted to a control system as a detection signal for, for example, tracking control (edge position control) of a metal strip. The required current output from the converter 11 is inputted to the recorder 12 to record the position of the edge of the metal material 50.

FIG. S (-9) shows another embodiment of the present invention.

@ In diagram S (-9), (21-1), (21-2
) is a metal material such as a steel pipe 6 at the detection end.
The electrodes (25-
1), (24-1) and (23-2), (24-2
) so that a metal material 60 exists between them. (3
0-1) and (,5O-2) are output from the electrodes (24-1) and (24-2), respectively, by the amplifiers, and the electrodes (23-1) and (24-1)! 5(il-1L (31
-2) is a converter and an amplifier (go-1).

The mu C output from (30-2) is converted into DCK.

(42-1), (42-2) Fi are AC oscillators, which transmit AC current to the electrodes (25-1) and (25-2) K, respectively.

supply 43 is a computing unit, and is an electrode (25-1).

The dimensions in two directions perpendicular to the length direction Kfi of the metal material 40 between (24-1), (23-2), and (24-2), which are orthogonal in this embodiment, are calculated.

Figure 2(b) K% In the system shown in Figure 3, the electrodes (25-1), (24-1) or (2!5-2
), (24-4) shows the relationship between the shielding dimension of the metal material 60 and the capacitance between the electrodes, that is, the electrode (2!1-1)
, (24-1) or (25-2), (24-2), if the shielding dimension of the metal material 60 in the length direction of the electrode O is defined as X, then the electrodes (25-1), (24-2) 1) Capacitance C between Seki or <25-2), (24-2)
is −x C= − mu ε! It is given by m=(L-x) - (3).

Here %d; distance between electrodes e = dielectric constant between electrodes L: Length of electrode.

This can be interpreted as a capacitance change, so if two pairs of electrodes are arranged so that they intersect at 90 degrees as shown in Figure 5, the cross-sectional roundness of metal materials such as steel pipes and rods and wires can be adjusted. Can be detected. Of course, as in Example O shown in FIG.
By increasing the number of electrode pairs in the length direction of the metal material or by changing the angle of the electrode pairs discretely or continuously in a plane perpendicular to the length direction of the metal material, a finer textured cross section of the metal material can be obtained. Profiles can be detected.

Next, the operation of the embodiment of the invention shown in FIG. 3 will be explained. respective AC oscillators (42-1);

When electrode (2M-1), (23-2) K AC current is supplied from (42-2), each electrode pair (2s-1),
(24-1) and (25-2) (24-2) A current proportional to the lengths X and X' parallel to the length direction of each electrode pair O shielded by the metal material 60 existing in the They are output from the electrodes (24-1) and (24-2), respectively.

The required currents output from the electrodes (24-1) and (24-2) are amplified by the respective amplifiers (50-1) and (50-2), respectively, and the transducers (51-1) and (!i1- '
In step 2), the signal is subjected to C/DC conversion and inputted as a DC voltage to the computing unit 4sK, and then inputted as a control signal to, for example, a rotational speed control system in a steel pipe hardening device. Nine converters (31-1) are input to the arithmetic unit 43.

Based on the signal from (31-2), in this embodiment, the diameters of the metal material 60 in two orthogonal directions in a plane perpendicular to the length direction Kll are calculated by the calculator 45, Squareness is understood.

Since this invention is constructed and operated as described above, it produces the following effects.

(1) The structure is simple and the position and shape of metal materials can be detected without contact.

(W) Signal processing is easy because it uses analog/4G detection.

(S) Since it uses capacitance, it has excellent reproducibility and high accuracy.

(4) It is possible to perform measurements with low accuracy without being affected by the scattering of the object to be measured.

(S) IIIJ It is completely unaffected by the dimension of the target object, and can be used to measure even thick and large materials.

(4) Since the circularity in the diameter of the metal material can be continuously measured, the state of the manufacturing process can be continuously monitored.

(7) Metal materials ranging from cold to high temperatures can be measured.

(8) Maintenance is easy.

[Brief explanation of the drawing]

Figures 1 (a) and (b) are explanatory diagrams showing an embodiment of the present invention, Figure 12 (b) is a diagram showing the principle of the invention, and Figure 3 (1) is an explanatory diagram showing an embodiment of the invention. A front view showing another embodiment, (b) is a plan view thereof. In the drawing, 50 s, 60 are metal materials, S, 4, 2
5-1°24-1.25-2.24-2 is an electrode, 15.
42-1゜42-2 is an AC oscillator, 10.30-1.5
0-2 is an amplifier. Applicant Nippon Steel Corporation

Claims (1)

[Claims] (1) Electrodes are provided so as to sandwich a metal material and face each other at intervals, and an alternating current oscillator is provided to supply an alternating current to one of the electrodes, and an alternating current is output from the other electrode. and an amplifier for amplifying a current corresponding to the size occupied by the metal material in a direction parallel to the electrodes between the electrode plates. A pair of electrodes are provided so as to sandwich a metal material and face each other so as to be rotatable in a plane perpendicular to the length direction of the metal material, with the symmetrical point of the electrodes as the center, and an alternating current is applied to one of the electrodes. an AC oscillator for supplying the metal material; Position and shape detection device. (3) Pairs of electrodes are arranged so as to sandwich the metal material and face each other, with an interval in the length direction of the metal material, and each pair of electrodes are arranged close to each other in a torso plane perpendicular to the length direction of the metal material. An alternating current oscillator is provided to supply an alternating current to one of the electrode pairs, and the metal A metal material O consisting of an amplifier that amplifies an electrical signal corresponding to the size occupied by the material.
Position and shape detection device.