JPH0664806A - Vibration damping device for steel strip - Google Patents

Abstract

PURPOSE:To provide a vibration damping device having the capability of effectively restraining the vibration of a travelling steel strip with the attracting force of an electromagnet. CONSTITUTION:Two pairs of electromagnets 5 are provided at upper and reverse sides of a travelling steel strip 1 in such a way as faced thereto. Also, a displacement gauge 4 is laid between the electromagnets 5 as a pair, relative to either side of the strip 1, and made to have a uniaxial system. Also, a plurality of electromagnets 5 and displacement gauges 4 as uniaxial in the breadthwise direction of the strip 1 are arranged, and provided at one or a plurality of positions in the lengthwise direction of the strip 1. In this case, displacement detected with the gauges 4, a differentiation signal for the displacement obtainable through a differentiator 6 and a value for electrical current flowing across the electromagnets 5 are respectively detected. In addition, a control means is installed to regulate the attracting force of the electromagnets 5 on the basis of respective detected values. A vibration damping device is thereby constituted. According to this construction, the vibration of the steel strip 1 due to disturbance can be restrained, and when the device is installed at a plating process line, for example, the fluctuation of a plating deposition amount can be prevented and the quality of a plated steel plate can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration suppressing device for suppressing the vibration of a running steel strip by using an electromagnet by a non-contact attraction force.

[0002]

2. Description of the Related Art As a conventional technique for suppressing the vibration of a traveling steel plate by utilizing the attractive force of an electromagnet, for example, Japanese Patent Laid-Open No.
There is a device disclosed in 62355.

In this technique, a surface on which a strip-shaped steel plate travels is defined as a symmetric surface, and a pair or a plurality of pairs of electromagnets are arranged facing each other at a required distance from the surface and form each pair. Based on the detection signal of the non-contact type steel plate position detector, which is provided in the vicinity of one of the electromagnets at a required interval between the surface on which the steel plate is to be run, and the detection signal of this steel plate position detector. A steel plate vibration suppression and position control device comprising a controller for performing signal processing such as proportionality, integration, and differentiation, and having a function for operating while switching the attraction force of each pair of electromagnets. is there.

[0004]

By the way, in the arrangement of the electromagnet and the displacement gauge in this technique, the steel strip displacement detection position of the displacement gauge and the attraction force acting position of the electromagnet are deviated from each other. And the vibration suppressing effect cannot be sufficiently obtained.

The present invention advantageously solves the above-mentioned problems of the prior art and provides a vibration suppressing device for effectively suppressing the vibration of the steel strip due to disturbance.

[0006]

SUMMARY OF THE INVENTION According to the present invention, two pairs of electromagnets that sandwich a traveling steel strip and oppose the front and back of the steel strip to exert an attractive force are provided. Of the electromagnet and the displacement gauge are arranged between the pair of electromagnets as a single axis in the width direction of the steel strip, and a plurality of such electromagnets and displacement gauges are arranged in the longitudinal direction of the steel strip. Displacement of the steel strip detected by a displacement gauge provided at one or more places, the differential signal of the displacement obtained by using a differentiator, and the current value of the electromagnet are detected, and the attraction force of the electromagnet is detected based on them. Is a vibration suppressing device for a steel strip, which is provided with a control means for controlling.

[0007]

The operation of the present invention will be described in detail below.

FIG. 1 is a connection diagram showing a structural example of a control means for one pair of electromagnets of the device of the present invention, and FIG. 2 is a perspective view showing a running portion of a steel strip.

First, in FIG. 2, 1 is a steel strip running while applying tension in the longitudinal direction, 2 is a plating tank for depositing zinc or the like on the steel strip, and 3 is the required zinc deposited in the plating bath 2. It is an air nozzle for blowing a slit-like gas such as nitrogen, which is applied with a constant pressure, for example, 1.2 kg / cm ² , so as to have an adhered amount, for example, about 30 mg / m ² .

Further, 4 is a displacement gauge for detecting the displacement of the steel strip 1 from the surface to be traveled, and 5 is a suction force for returning the steel strip to the surface to be traveled, which acts on the steel strip in a non-contact manner. It is an electromagnet.

The displacement meter 4 is arranged at the center of the two electromagnets 5 in order to prevent the displacement between the steel strip displacement detection position measured by the displacement meter 4 and the position where the attractive force is applied as much as possible. When an eddy current type displacement meter is used as the displacement meter 4, the magnetic field generated by the electromagnet 5 is arranged at a constant interval so as not to affect the displacement meter 4.

Then, the displacement gauge 4 and the electromagnet 5 are combined,
These are arranged on the front side of the steel strip surface on an axis perpendicular to the steel strip surface at a required interval from the steel strip, and only the electromagnet 5 is arranged on the back side of the steel strip surface. Four electromagnets 5 are combined to form a pair. A plurality of pairs of the displacement gauge 4 and the electromagnet 5 are arranged above the air nozzle 3 in the width direction of the steel strip 1 and arranged in one or more places in the running direction of the steel strip.

Next, in the control means shown in FIG.
The amount of vibration detected by the steel strip 1 as the amount of displacement from the surface to be traveled, the differential signal of the displacement obtained by using the differentiator 6 configured by an analog circuit, and the current value detected by the current detector 7. Is input to the control computer 9 as a digital signal through the A / D converter 8.

On the other hand, the digital computer 10 has a strip size such as a plate thickness and a plate width calculated or measured separately,
Data such as material parameters, electromagnet parameters, tension, and plate passing speed are input, optimal control gains, parameters, etc. are calculated and set values are given to the control computer 9.

In the control computer 9, the voltage command value calculated by the vibration model of the steel strip and the model of the electromagnet, the displacement amount, the differentiated displacement amount, the detected value of the current value of the electromagnet, etc. is passed through the D / A converter 11. Electromagnetic drive amplifier 1
Give to 2.

The electromagnet driving amplifier 12 is for individually exciting the electromagnets 5 on the front and back sides of the steel strip surface.

With these devices, the vibration of the steel strip 1 is suppressed to, for example, within ± 1.5 mm, and the variation of the amount of plating applied due to the variation of the distance between the air nozzle 3 and the steel strip 1 due to the vibration of the steel strip is prevented. For example, it is suppressed within ± 2 g / m ² .

[0018]

FIG. 3 shows an embodiment in which vibration of a steel strip is suppressed by the apparatus of the present invention, the horizontal axis is the time axis, and the vertical axis is the displacement of the steel strip from the surface through which the steel strip should pass. is there.

In this case, the preconditions are: Steel strip thickness: 0.6 (mm) Steel strip amplitude: 1500 (mm) Tension per unit area of steel strip: 1.6 (kg /
mm ² ) Steel strip traveling speed: 80 (mp
m)

At time t = 0, except for the disturbance given as the displacement from the surface through which the steel strip should pass, in the case of the conventional example in which the apparatus according to the present invention is not used, the steel strip is within the supported section. Although the vibration continues due to the natural vibration, the amplitude is sharply reduced by the use of the device of the present invention, and the effect of suppressing the vibration is remarkably exhibited.

[0021]

As described above, according to the vibration suppressing device of the present invention, the electromagnet is opposed to the front and back of the steel strip across the traveling steel strip, and the attraction force acting on the steel strip is controlled by this electromagnet. It is possible to effectively suppress the vibration of the steel strip due to the disturbance by controlling by means of the means. Can be improved.

[Brief description of drawings]

FIG. 1 is a connection diagram showing a configuration example of control means for one pair of electromagnets of the device of the present invention.

FIG. 2 is a perspective view showing an example of a running portion of the steel strip in FIG.

FIG. 3 is a drawing showing an example of a vibration suppressing effect when vibration of a steel strip is suppressed by the device of the present invention.

[Explanation of symbols]

 1 Steel Strip 2 Plating Tank 3 Air Nozzle 4 Displacement Meter 5 Electromagnet 6 Differentiator 7 Current Detector 8 A / D Converter 9 Control Computer 10 Digital Computer 11 D / A Converter 12 Electromagnetic Drive Amplifier

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[Procedure amendment]

[Submission date] October 27, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction content]

First, in FIG. 2, 1 is a steel strip running while applying tension in the longitudinal direction, 2 is a plating tank for depositing zinc or the like on the steel strip, and 3 is the required zinc deposited in the plating bath 2. It is an air nozzle that blows a slit-like gas such as nitrogen, which is applied with a constant pressure, for example, 1.2 kg / cm ² , so as to have an adhered amount, for example, about 30 g / m ² .

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuo Oshinotani 1117 Kitakaname, Hiratsuka City, Kanagawa Prefecture Tokai University Faculty of Engineering

Claims (1)

[Claims] 1. A pair of electromagnets which face the front and back of the steel strip and which exert an attractive force across the traveling steel strip are disposed between a pair of electromagnets on one side of the steel strip surface. Displacement gauges are arranged in a longitudinal direction of the steel strip, and a plurality of electromagnets and displacement gauges are arranged in the widthwise direction of the steel strip. The amount of displacement of the steel strip detected by, and the differential signal of the amount of displacement obtained using a differentiator, and the current value of the electromagnet are detected, and a control means for controlling the attraction force of the electromagnet based on them is provided. A vibration suppressing device for a steel strip, which is characterized in that