Meandering amount detection method and meandering control method for metal strip

Abstract

A meandering amount detection method for a metal strip traveling in a state of being overlapped in a plurality of stages, includes: calculating an end portion position in a width direction of a metal strip in each stage using an angle formed by a reference direction, which is any direction determined from a reference point, and a direction connecting the reference point and an end portion position in a width direction of a metal strip in each stage, a distance between the reference point and an end portion position in a width direction of a metal strip in each stage, and a distance between a straight line including a width direction of the metal strip and the reference point; and calculating a meandering amount of a metal strip in each stage based on the calculated end portion position in the width direction of the metal strip in each stage.

Claims

1. A meandering amount detection method for detecting a meandering amount of a metal strip traveling in a state of being overlapped in a plurality of stages at intervals, the method comprising: calculating an end portion position in a width direction of the metal strip in each of the plurality of stages using an angle formed by a reference direction, wherein the reference direction is determined from a reference point, and a direction connecting the reference point and the end portion position in the width direction of the metal strip in each of the plurality of stages, a distance between the reference point and the end portion position in the width direction of the metal strip in each of the plurality of stages, a distance between a straight line including the width direction of the metal strip and the reference point; and calculating the meandering amount of the metal strip in each of the plurality of stages based on the calculated end portion position in the width direction of the metal strip in each of the plurality of stages.

2. The meandering amount detection method for detecting the meandering amount of the metal strip according to claim 1, wherein the calculating the end portion position in the width direction of the metal strip in each of the plurality of stages includes causing a distance meter to scan about the reference point, and setting a scan angle at which a detection value suddenly changes from a relationship between the scan angle and the detection value of the distance meter as an angle formed by the reference direction and the direction connecting the reference point and the end portion position in the width direction of the metal strip in each of the plurality of stages.

3. A meandering control method for the metal strip, comprising: detecting the meandering amount of the metal strip by using the meandering amount detection method for detecting the meandering amount of the metal strip according to claim 2; and controlling the meandering of the metal strip based on the meandering amount of the metal strip.

4. A meandering control method for the metal strip, comprising: detecting the meandering amount of the metal strip by using the meandering amount detection method for detecting the meandering amount of the metal strip according to claim 1; and controlling the meandering of the metal strip based on the meandering amount of the metal strip.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a side view illustrating a configuration of a looper to which a meandering control device for a metal strip, which is an example, is applied.

(2) FIG. 2 is a block diagram illustrating a configuration of a meandering control device for a metal strip, which is an example.

(3) FIG. 3 is a diagram for explaining parameters detected by a distance meter illustrated in FIG. 2.

(4) FIG. 4 is a diagram illustrating the relationship between a scan angle and a detection value of the distance meter.

REFERENCE SIGNS LIST

(5) 1 LOOPER 2, 2a, 2b, 2c, 2d METAL STRIP 3 STEERING ROLL 4 LOOPER CAR 10 MEANDERING CONTROL DEVICE FOR METAL STRIP 11 DISTANCE METER (REFERENCE POINT) 12 MEANDERING DETECTOR 13 CONTROL DEVICE

DETAILED DESCRIPTION

(6) A configuration of a meandering control device for a metal strip, which is an example, will be described below with reference to the drawings.

Configuration of Looper

(7) A configuration of a looper to which a meandering control device for a metal strip, which is an example, is applied will be first described with reference to FIG. 1.

(8) FIG. 1 is a side view illustrating a configuration of a looper to which a meandering control device for a metal strip is applied. As illustrated in FIG. 1, in a looper 1 to which a meandering control device for a metal strip is applied, a metal strip 2 is passed through to reciprocate between a steering roll 3 and a looper car 4. Therefore, metal strips 2 (2a, 2b, 2c, and 2d) in a plurality of stages are present at intervals in the looper 1. In this example, the meandering control device for a metal strip detects the meandering amount of the metal strip 2 in the looper 1, in any stage, in a space-saving and cost-saving manner, and corrects the meandering of the metal strip 2.

Configuration of Meandering Control Device for Metal Strip

(9) A configuration of a meandering control device for a metal strip, which is an example, will now be described with reference to FIGS. 2 and 3.

(10) FIG. 2 is a block diagram illustrating a configuration of a meandering control device for a metal strip, which is an example. As illustrated in FIG. 2, a meandering control device 10 for a metal strip includes a distance meter 11, a meandering detector 12, and a control device 13.

(11) As illustrated in FIG. 3, the distance meter 11 is constituted of a two-dimensional scanner (two-dimensional distance sensor) provided on the upper side of the metal strip 2 in the uppermost stage and on one side of the end portion in the width direction of the metal strip 2. The distance meter 11 detects values of parameters , .sub.i, and l.sub. by scanning a range of a predetermined angle, and outputs an electric signal indicating the detected values to the meandering detector 12. The position of the distance meter 11 is set as a reference point, and the lower side in the vertical direction of the distance meter 11 is set as a reference direction. The parameter represents an angle (>0) from the scan start direction (the reference direction) of the distance meter 11, the parameter .sub.i represents an angle (an angle formed by the reference direction and a direction connecting the reference point and an end portion position in the width direction of the metal strip in each stage) when end surfaces (points A to D) of the metal strip 2 in the i-th stage (i=1 to 4 in this example) is detected, a parameter h represents a height of the installation position of the distance meter 11 from a ground F, a parameter h.sub.i represents a height of the metal strip 2 in the i-th stage from the ground F, and the parameter l.sub. represents a measurement value of the distance meter 11 at the angle (a distance between the reference point and an end portion position in the width direction of the metal strip in each stage). Note that, in the above description, h-h.sub.i is a distance between a straight line including the width direction of the metal strip and the reference point (a length of a perpendicular line from the reference point to the straight line).

(12) The distance meter 11 may be constituted of a combination of a three-dimensional scanner and a plurality of one-dimensional distance meters. The installation position of the distance meter 11 is not necessarily on the upper side of the metal strip 2 in the uppermost stage. By installing the distance meter 11 not only on one side of the end portion in the width direction of the metal strip 2, but also on the other end portion side, improvement of detection accuracy and a backup function at the time of a failure may be realized.

(13) The meandering detector 12 detects a meandering amount s.sub.i of the metal strip 2 in the i-th stage based on the electric signal output from the distance meter 11, and outputs an electric signal indicating the detected meandering amount s.sub.i to the control device 13. Specifically, when the distance meter 11 is caused to scan in a direction in which the angle increases from 0, the measurement value l.sub. of the distance meter 11 greatly decreases at the end surfaces (the points A to D) of the metal strip 2, as illustrated in FIG. 4. The change in the measurement value l.sub. is expressed by Equations (1) and (2). In the equations, l.sub..sub.i represents the measurement value l.sub. of the distance meter 11 corresponding to the end surface of the metal strip 2 in the i-th stage.

(14) $\begin{array}{cc}\mathrm{Immediately}\mathrm{Before}\mathrm{End}\mathrm{Surface}\mathrm{Detection}:l_{{}_i}=\underset{a.fwdarw.-0}{\lim }{l}_{{}_i+a}=h/\cos {}_i& \left(1\right)\end{array}$$\begin{array}{cc}\mathrm{Immediately}\mathrm{After}\mathrm{End}\mathrm{Surface}\mathrm{Detection}:l_{{}_i}=\underset{a.fwdarw.+0}{\lim }{l}_{{}_i+a}=\left(h-h_i\right)/\cos {}_i& \left(2\right)\end{array}$

(15) Therefore, the meandering detector 12 detects a meandering amount of the metal strip 2 in the i-th stage based on the angle .sub.i at the time when the measurement value l.sub. of the distance meter 11 suddenly changes. In other words, assuming that the angle .sub.i when the meandering amount of the metal strip 2 in the i-th stage is 0 is .sub.a0, the meandering detector 12 calculates a meandering amount s.sub.i of the metal strip 2 in the i-th stage by Equation (3). In Equation (3), l.sub..sub.a0 represents the measurement value l.sub. of the distance meter 11 when the meandering amount of the metal strip 2 in the i-th stage is 0.

(16) $\begin{array}{cc}\begin{array}{c}{s}_i=l_{{}_{a0}}\sin {}_{a0}-l_{{}_i}\sin {}_i\\ =\left(h-h_{}\right)\sin {}_{a0}/\cos {}_{a0}-\left(h-h_{}\right)\sin {}_i/\cos {}_i\\ =\left(h-h_i\right)\tan {}_{a0}-\left(h-h_i\right)\tan {}_i\\ =\left(h-h_i\right)\left(\tan {}_{a0}-\tan {}_i\right)\end{array}& \left(3\right)\end{array}$

(17) The control device 13 performs control so that the meandering amount s.sub.i of the metal strip 2 in the i-th stage detected by the meandering detector 12 falls within a predetermined range. Specifically, the control device 13 corrects the meandering of the metal strip 2 in the i-th stage by tilting the steering roll directly connected to the metal strip 2 in the i-th stage.

(18) As is apparent from the above description, in the meandering control device 10 for a metal strip, the meandering detector 11 calculates the end portion position in the width direction of the metal strip 2 in each stage using the heights h and h.sub.i, the angle .sub.i, and the measurement value l.sub. of the distance meter 11, and calculates the meandering amount s.sub.i of the metal strip 2 in each stage based on the calculated end portion position in the width direction so that the meandering amount of the metal strip 2 in the looper 1 can be detected in any stage in a space-saving and cost-saving manner.

(19) Although the example applied has been described above, this disclosure is not limited by the description and the drawings constituting a part of the disclosure according to the example. For example, since my methods are characterized by being used in a place where metal strips are overlapped in a plurality of stages, they can also be applied to a place other than a looper (e.g., the vicinity of a joining portion of metal strips when a plurality of metal strip delivery devices is provided). As described above, other examples, operation techniques, and others implemented by those skilled in the art and others based on this example are all included in the scope of the disclosure.

INDUSTRIAL APPLICABILITY

(20) I make it possible to provide a meandering amount detection method for a metal strip, which is capable of detecting a meandering amount of a metal strip in a looper, in any stage, in a space-saving and cost-saving manner. It is possible to provide a meandering control method for a metal strip capable of detecting a meandering amount of a metal strip in a looper, in any stage, in a space-saving and cost-saving manner and correcting the meandering of the metal strip.