JPH06167307A - Strip lateral deviation detection device - Google Patents

Abstract

(57) [Summary] [Purpose] To accurately detect the amount of lateral deviation of a running strip (strip) from a reference position where it should run, even in adverse environments such as hot dip galvanizing lines. Constitution: Position detection means for the left and right width edges of the strip is loaded on the moving means, and the left and right position detection means are sandwiched between the width edges of the strip by the driving means, control means, etc.
The amount of lateral deviation of the strip is detected by causing the movement amount detecting means to read and output the movement amount of the differential means according to this movement so as to move in conjunction with the edge portion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a strip lateral deviation amount detecting device for detecting a lateral deviation amount of a traveling strip (hereinafter referred to as a strip) from a reference position to be traveled, and particularly to hot dip galvanizing. Suitable for use in a bad environment such as a line, suitable for accurately and easily detecting the amount of lateral deviation from a reference position at which a strip of continuously running strip-shaped thin steel plate, etc., should run. The present invention relates to a strip lateral deviation amount detection device.

[0002]

2. Description of the Related Art For example, in a hot-dip galvanizing line in the iron manufacturing industry, a plating apparatus as shown in the side sectional view of FIG. 1 and the sectional view taken along the line II-II of FIG. 2 is used.

This plating apparatus includes a molten zinc bath 10 and
The sink roll 12 is arranged so as to be immersed therein, and a main part such as a pair of wiping nozzles 14 and the like arranged above the sink roll 12 so as to face the front and back surfaces of the strip 8, respectively.

The strip 8 to be plated is once vertically drawn by the sink roll 12 after being drawn and dipped into the molten zinc 10A in the molten zinc bath 10 as shown by the dashed arrow A in FIG. It runs so as to pass between the two wiping nozzles 14.

At this time, the strip 8 adheres to the surface of the strip 8 and surplus molten zinc pulled up from the molten zinc bath 10 is blown off by an appropriate collision force of the gas flow jetted from the wiping nozzle 14. By
Finished to the required plating thickness.

The strip 8 that has passed through the wiping nozzle 14 passes while being restrained by a support roll 16 provided above it so as not to shake, and then enters into an alloying furnace 18 provided above it. I am going to go.

In such a plating apparatus, if an attempt is made to increase the traveling speed of the strip 8 for the purpose of increasing productivity, molten zinc will be strongly drawn between the sink roll 12 and the strip 8 and the hydroplane As a phenomenon, the frictional force between the strip 8 and the sink roll 12 is drastically reduced, and as a result, the strip 8 has some problems such as its shape defect, partial tension imbalance, or mechanical misalignment. Disturbance may cause the skid to easily skid, meandering to prevent stable operation, and in extreme cases, the strip 8 may deviate to the side of the sink roll 12, resulting in damage to the plating apparatus or inability to operate. Sometimes becomes.

Therefore, conventionally, in order to reduce the occurrence of meandering caused by the strip 8 sliding sideways, a large number of thin grooves called grooves are provided on the surface of the sink roll 12 at a required pitch, and the sink roll 12 and the strip are It is carried out so as to facilitate the discharge of the molten zinc drawn in between 8 and 8 so as not to reduce the frictional force.

However, this groove transfers a pattern called a groove mark, which is unfavorable in terms of quality, to the surface of the strip 8, and it is not suitable for the quality required in recent years. Therefore, it is desired to eliminate it. Is becoming more common.

In order to eliminate the groove mark and to prevent the strip 8 from meandering, the sink roll 12 is designed to reduce the lateral displacement of the strip 8 from the reference traveling position.
Is required to be tilted in the direction shown by the solid arrow B in FIG. 2, and for this purpose, it is essential to provide a strip lateral deviation amount detection device to accurately detect the traveling position of the strip 8. is there.

However, various restrictions are imposed on the strip lateral deviation amount detecting device to be applied here.

That is, the installation position of the strip lateral deviation detection device is limited to between the support roll 16 and the alloying furnace 18, and the detection space in this portion is 20 in the vertical direction.
Only about 0 mm can be secured, the ambient temperature in this vicinity reaches 150 ° C, a large amount of zinc powder is scattered, the width change of the strip 8 reaches 1000 mm, scratches and patterns on the plated surface. It is necessary to meet many conditions such as non-contact detection so as not to put on, workers always enter and work near the plating equipment, detection accuracy of 1 mm or more is required, etc. is there.

Under such severe conditions, the strip 8
In order to detect the lateral shift amount of
As shown in FIG. 2, two image sensors 20 that image both edges of the strip 8 at separate positions in front of the plating apparatus 20 are shown.
Has been attempted to be known from the video signal of the strip 8 taken by the above.

[0014]

However, in such a method, an operator or other object stands between the image sensor 20 and the strip 8 as an object, and the field of view is obstructed and detection becomes impossible. Since a wide field of view corresponding to the width change of the strip 8 (about 500 mm on one side) is required, it is not possible to detect a slight position change due to the limitation of resolution. If it is installed near the lens, it must be imaged with a wide-angle lens, and there is a practical problem because the detected value fluctuates significantly at the edge of the visual field due to the positional change of the strip 8 in the perspective direction. The reality was that I couldn't master it.

In order to solve such a problem, for example, Japanese Patent Laid-Open No. 63-282607 or Japanese Utility Model Laid-Open No. 62-62-
As disclosed in Japanese Patent No. 14310, by arranging the image sensor 20 immediately in front of both edges of the strip 8 and moving them in the width direction corresponding to the width of the strip 8, the image sensor Attempts have been made to increase the resolution by detecting a wide range without widening the field of view. However, even with such a method, because the contrast of the optical image cannot be strongly obtained, and because external light has a large effect as a disturbance, not only lacking accuracy and stability, There is a drawback that the lateral shift amount of the strip 8 has to be calculated by performing extremely complicated signal processing from the movement amount of each of the two image sensor main bodies and the position of the captured image on the screen. .

An improved version of this is disclosed in JP-A-57 / 1982.
No. 172203 or JP-A No. 1-210813, the load of signal processing is reduced by interlocking the detection units at both ends, but it is still insufficient.

The present invention has been made to solve the above-mentioned conventional problems, and is suitable for accurately and easily detecting the lateral deviation amount of a strip from a reference position where it should travel.
An object of the present invention is to provide a strip lateral deviation amount detection device.

[0018]

SUMMARY OF THE INVENTION According to the present invention, in a strip lateral deviation amount detecting device for detecting a lateral deviation amount of a strip from a reference position, a left lateral edge portion and a right lateral edge portion of the strip are respectively detected. Position detecting means, left and right moving means for loading and moving the left and right position detecting means respectively in the width direction of the strip, a drive source for the left and right moving means, and the left and right A left and right transmission means for transmitting the driving force of the drive source to the moving means, and a difference that is interlocked with the movements of the left and right transmission means and differential according to the movement of the left and right moving means. A detection unit main body including a moving unit and a moving amount detecting unit for knowing the moving amount of the differential unit and outputting the moving amount as a lateral deviation amount;
And processing the output signals from the left and right position detecting means so as to match the left and right position detecting means with the positions near both width edges of the strip, and the left and right position detecting means. And left and right position detecting means are automatically set close to both width edges of the strip, and then both width edges of the strip are provided. The movement amount of the differential means, which is moved according to the left and right moving means, is read and output by the movement amount detecting means. By detecting the amount of lateral deviation of the strip,
The above object is achieved.

Further, the detection unit main body and the control means are integrally housed in a case for protecting them from the ambient atmosphere and installed between the wiping nozzle of the plating apparatus and the alloying furnace.

[0020]

According to the present invention, the left and right position detecting means for detecting the left and right width edges of the strip are loaded on the left and right moving means, respectively, and the driving source of the moving means and its driving force By the transmission means and the control means, the width edges of the strip are made to coincide with each other, and the width edges of the strip are sandwiched so as to integrally follow the width edges of the strip. The amount of lateral displacement of the strip is detected by controlling the movement and reading and outputting the movement amount of the differential means that is differential according to the movement of the left and right position detecting means by the movement amount detecting means. I have to. Therefore, it is possible to accurately and easily detect the amount of lateral deviation of the strip from the reference position.

Further, the main body of the strip side deviation amount detecting device and the control means comprising the above means are integrally housed in a case for protecting from the ambient atmosphere, and the wiping nozzle of the plating device and the alloying furnace are integrated. When installed in between, it can be used even in a bad environment such as a plating apparatus.

[0022]

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

3 to 5 are drawn for explaining the present embodiment, and FIG. 3 is a perspective view showing the appearance of the main body of the detecting portion of the strip lateral deviation detecting device of the present embodiment.
FIG. 4 is a perspective view showing the internal structure of the detection unit main body, and FIG. 5 is a circuit diagram showing the outline of the controller.

In the following, with respect to the numbers indicating the respective parts in the drawings, those corresponding to the left side are L, those corresponding to the right side are R,
Those common to the left and right are denoted by a C symbol to distinguish them.

As shown in these figures, this detection device comprises a detection section main body and a controller.

As shown in FIG. 4, the detector main body 22 includes position detectors 24L and 24R, slide bases 26L and 26R,
Motors 28L and 28R, drive wheels 30L and 30
R, driven wheels 32L and 32R, intermediate wheel 34
L and 34R, presser wheels 36L and 36R, presser wheels 38L and 38R, transmission belts 40L and 40R, sliding base 26C, movement amount detector 42, and the like, which are external parts, heat, and dust. It is integrally housed in a case 44 as shown in FIG. 3 so as to be protected from the like.

The case 44 is provided with an elongated window 44A on the front side thereof along the moving range of the position detectors 24L and 24R and the like, so as not to obstruct the visual field of the position detectors 24L and 24R. In addition, in order to prevent the internal temperature from rising abnormally due to the heat applied from the outside or the internal heat generation, and to prevent the external dust from entering through the window 44A, the side end portion is provided. An appropriate amount of pressurized air for cooling is blown from the provided purge air supply port 44B.

The position detector 24L is used for the purpose of detecting whether or not there is the strip 8 in front of it, that is, the spot edge of the width edge of the strip 8, and the strip 8 in front of this. If there is, it outputs a high level signal.

As the position detector 24L, in the embodiment, from the viewpoint of detection sensitivity, accuracy, etc., a laser reflection photoelectric type detection of a system of projecting a laser beam and detecting the reflected light thereof is received. Vessels are used.

The slide base 26L slides smoothly on the guide rail 46L, and the position detector 24 loaded on the slide base 26L.
L is used to enable smooth linear movement in the width direction of the strip 8.

The motor 28L is a prime mover for locating the position detector 24L loaded on the slide table 26L at the width edge of the strip 8, and a pulse motor is used here for ease of control. However, in some cases, a servomotor with an encoder may be used.

The power transmission belt 40L is stretched between a drive wheel 30L fixed to the shaft of the motor 28L and a driven wheel 32L rotatably supported by a bearing 48L, and both lower ends thereof are The driving force of the motor 28L is fixed to the bracket 50L and the bracket 52L attached to the sliding base 26L, and the driving force of the motor 28L is applied to the sliding base 2L.
It works to transmit to 6L.

The power transmission belt 40L is used for transmitting motion without slipping, and a chain is used in this embodiment.

The intermediate wheel 34L is fitted to one end of a rotary shaft 56 which is rotatably supported by a bearing 54 fixed on the slide base 26C, and the holding wheel 36L is fitted to one end of a rotary shaft 58. Fitted, and further presser wheel 38L
Is fitted to one end of the other rotary shaft 58.

In contrast to the above-mentioned 24L to 38L and the like, 24R to 38R and the like in the figure are merely in point-symmetrical arrangement relationship, and their specifications and purposes are exactly the same.

Intermediate wheel 34L and intermediate wheel 34
R, or presser wheel 36L and presser wheel 38
R, or presser wheel 38L and presser wheel 36R
As for the fitting portions such as, if at least any one pair is transmission-coupled to each other, the other pairs are not necessarily transmission-coupled to each other but may be loose. , In the examples,
As will be described later, the intermediate wheel 34L and the intermediate wheel 3 in which the winding angles of the transmission bands 40L and 40R are the largest.
4R and 4R are fixed to the shaft 56, and are used in a transmission-coupled state.

In this case, the presser wheels 36L and 36L
R, presser wheels 38L and 38R, etc.
And 40R, etc., to increase the wrapping angle around the intermediate wheels 34L and 34R, and the power transmission bands 40L and 40R.
It works to properly determine the route for extending R so that it does not interfere with other parts.

Driving wheel 30L and driven wheel 32L
The transmission band 40L stretched between and is wound around the upper side of the press rolls 36L and 38L and the lower side of the intermediate wheel 34L in the middle of the upper side thereof.

On the other hand, the transmission band 40R stretched between the drive wheel 30R and the driven wheel 32R is wound on the lower side of the pressing wheels 36R and 38R and the upper side of the intermediate wheel 34R in the middle of the lower side thereof. It is hung to attach.

The slide base 36C includes a bearing 54, a rotary shaft 56,
58, intermediate wheels 34L and 34R, presser wheel 36
L, 36R, 38L, 38R, etc. are loaded, and these are integrally and smoothly linearly moved on the guide rail 46C, and the movement amount of this is transmitted to the movement amount detector 42.

The movement amount detector 42 may be of any type as long as it is a transducer capable of converting the movement amount of the sliding base 26C into an electric signal.
In the embodiment, a differential transformer type linear detector is used.

The output signal of the movement amount detector 42, that is, the output signal of the lateral deviation amount detecting device, is the strip 8
Represents the amount of lateral deviation of

The operation of the detector body 22 will be described below.

The slide base 26C has the slide base 26L and the slide base 26R when the slide base 26C is at the central position of the detection unit main body 22.
The transmission belt 40L and the transmission belt 40R are set so as to be symmetrical with respect to each other with respect to the center position of the detection unit main body 22.

Under the conditions set as described above, when the motor 28L is rotationally driven in the direction of the solid line arrow in order to move the position detector 24L to the left as shown by the solid line arrow, the transmission belt 40L also moves in the solid line arrow. Intermediate wheel 34L which is moved in the direction of and is loaded on the slide table 26C.
Is rotated to the right as indicated by the solid arrow.

When the intermediate wheel 34L is rotated to the right, the intermediate wheel 34R fixed to the intermediate wheel 34L via the rotary shaft 56 is also rotated to the right as indicated by the solid arrow. (This is called the first operating state)

At this time, if the position detector 24R is in a stopped state, that is, the transmission belt 40R is stationary, the intermediate wheel 34R is rotated clockwise to support the shaft 56 supporting the intermediate wheel 34R. , Bearing 54, slide base 56
A reaction force is generated in C, etc., and as a result, the slide base 26C moves in the direction of the solid line arrow (leftward) in accordance with the drive amount of the motor 28L.
Be forced to move to.

This movement amount is read by the movement amount detector 42, and is output as a lateral shift amount to the left.

On the contrary, when the motor 28R is rotationally driven in the direction of the broken line arrow to move the position detector 24R to the right as shown by the broken line arrow, the transmission belt 4 is moved.
0R is also moved in the direction of the dashed arrow, and slide base 26C
The intermediate wheel 34R loaded on the upper side is rotated to the right as shown by the broken line arrow.

When the intermediate wheel 34R is rotated to the right, the intermediate wheel 34L fixed to the intermediate wheel 34R via the rotary shaft 56 is also rotated to the right as indicated by the broken line arrow. (This is called the second operating state)

At this time, if the position detector 24L is stopped, that is, the transmission belt 40L is stationary, the intermediate wheel 34L is rotated clockwise to support the shaft 56 supporting the intermediate wheel 34L. , Bearing 54, slide 26
A reaction force is generated in C and the like, and as a result, the slide base 26C moves in the direction of the broken line arrow (to the right) according to the drive amount of the motor 28R.
Be forced to move to.

This moving amount is read by the moving amount detector 42, and is output as a lateral shift amount to the right.

Further, in order to move the position detector 24L to the left as shown by the solid arrow, the motor 28L is rotationally driven in the direction of the solid arrow, and the position detector 24R is moved to the right as shown by the broken arrow. Motor 2 to move
When 8R is rotationally driven in the direction of the broken arrow, that is, when the above-mentioned first operating state and second operating state occur simultaneously (during opening operation), the power transmission bands 40L and 40R are moving together. Therefore, the intermediate wheels 34L and 34R are only rotating to the right (solid arrow direction = broken arrow direction),
No reaction force is generated on the shaft 56, the bearing 54, the sliding base 26C, and the like, so that the sliding base 26C is not moved, and the output signal of the lateral deviation amount from the movement amount detector 42 becomes zero.

On the other hand, the position detector 24L and the position detector 2
If the 4Rs move simultaneously in the opposite direction to the above (during the closing operation), the intermediate wheel 34L and the intermediate wheel 34R
Rotates only in the opposite direction to the left during the opening operation, and similarly, the slide base 26C is not moved in either direction. Therefore, the output signal of the lateral deviation amount from the movement amount detector 42 is It becomes zero.

That is, the position detector 24L and the position detector 2
When the 4Rs are positioned so as to be symmetrical with respect to the center position of the detection unit main body 22, the slide base 26C is always positioned at the center of the detection unit main body 22, and therefore the movement amount detector 42 The output signal of the lateral shift amount of is zero.

As is clear from the above description, this constitutes a kind of differential mechanism, and the slide base 26C moves according to the difference in the moving amount between the slide base 26L and the slide base 26R. It can be moved by an amount. (Hereinafter, this is called differential operation).

When the slides 26L, 26C, 26R and the like move to the right, a + sign is attached, and when they move to the left, a-sign is attached,
When the amount of movement of the sliding base 26L is L, the amount of movement of the sliding base 26R is R, and the amount of movement of the sliding base 26C is C, the following relational expressions are established between them.

C = (L + R) / 2 (1)

If the width of the strip 8 is constant and the position detectors 24L and 24R are always moving following both edges of the strip 8 (this is called parallel operation), their movements are performed. The quantity relationship is L = R (2), and therefore the above equation (1) is C = (L + L) / 2 = L (3) or C = (R + R) / 2 = R (4). Therefore, it is obvious that the lateral shift amount of the strip 8 can be known by knowing the moving amount of the slide table 26C (output of the moving amount detector 42).

The main body 22 of the detection unit skillfully creates the opening operation, the closing operation, the parallel operation, the differential operation, etc. as described above.
In addition, it is for detecting the lateral deviation amount, which is surely driven by the controller described below.

The controller 59 includes the position detectors 24L and 24L.
It is for controlling the movement of the motors 28L and 28R by receiving an output signal of R or the like, and its schematic circuit is shown in FIG.

In the figure, 60L and 60R are input terminals, to which the position detector 24 of the detector main body 22 is attached.
The output terminals of L and 24R are respectively connected via lead wires, and 62L and 62R are output terminals, to which the input terminals of motors 28L and 28R are connected respectively via lead wires. There is.

If there is a strip 8 in front of the position detector 24L, its output signal becomes high level, which is input to the AND circuit 66L via the OR circuit 64L to open this gate.

The AND circuit 66L outputs the drive pulse applied from the transmission circuit 68 when the gate is opened, and this is output to the motor drive circuit 70L.
To the input terminal O on the open side.

By applying a pulse signal to the open side input terminal O of the motor drive circuit 70L, the motor 28L succeeding to this is moved so that the position detector 24L moves from the inside of the strip 8 toward the width edge portion. Rotate to.

The position detector 24L is located at a position where the strip 8 disappears in front of it, that is, this is the strip 8
When the output signal comes to a position outside the width edge of the and becomes a low level output signal, the gate of the AND circuit 66L is closed and the input signal to the open side input terminal O of the motor drive circuit 70L. Disappears and the motor 28L is stopped, so that the position detector 24L is positioned immediately outside the width edge of the strip 8.

The transmitting circuit 68 is composed of the motors 28L and 28R.
Is for generating a driving pulse for determining the rotation speed of the.

The input terminal 72 connects the position detectors 24L and 24R located outside the width edge of the strip 8 and
It is for moving toward the width edge of the strip 8 (hereinafter referred to as a closing operation), and is closed by applying a pulse for the closing operation automatically or manually generated to this. The operation is started.

The flip-flop circuit 74L is for determining the start and end of the closing operation, and when a pulse for the closing operation is applied to the input terminal 72, this is set and a high level signal is held. Output as A and continue to this
The gate of the ND circuit 76L is opened.

The AND circuit 76L outputs the drive pulse applied from the transmission circuit 68 when the gate is opened, and the drive pulse is supplied to the motor drive circuit 70L via the OR circuit 78L and the AND circuit 80L. It is input to the closed side input terminal C.

As a result, the motor 28L connected to the motor drive circuit 70L rotates and moves the position detector 24L toward the width edge portion of the strip 8.

At the moment when the position detector 24L reaches the width edge of the strip 8, its output becomes high level, and the reset side input terminal R of the flip-flop circuit 74L becomes high level.

The flip-flop circuit 74L inverts its output to a low level by temporarily setting the reset-side input terminal R to a high level, and then closes the gate of the AND circuit 76L succeeding to this, thereby ORing it. Circuit 78L
And the motor drive circuit 70 via the AND circuit 80L.
The driving pulse input to the L-side closed side input terminal C is stopped, and the motor 28L is stopped.

That is, the position detector 24L includes the strip 8
It is stopped at the position where it reaches the width edge of. Reference numeral 82L is a one-shot multivibrator, which generates a pulse having a short time width at the moment when the closing operation is completed, that is, at the moment when the position detector 24L reaches the width edge of the strip 8, and sends the position detector 24L backward. (Hereinafter, this is referred to as opening and closing motion.)
Accordingly, the position detector 24L functions to stop at a position in the vicinity of the width edge of the strip 8 and not on the width edge.

This opening and closing movement amount is indispensable for correcting further movement of the position detector 24L due to inertia after the closing operation is completed.

One-shot multivibrator 82L
Is triggered at the moment when the position detector 24L reaches the width edge of the strip 8 and the output of the flip-flop circuit 74L is inverted to the low level, and transmits a pulse having a required width to the input terminal of the OR circuit 64L.

At this time, the pulse signal output from the OR circuit 64L is applied to the open side input terminal O of the motor drive circuit 70L via the AND circuit 66L, and the position detector 24L is moved from the width edge portion of the strip 8. The motor 28L is rotated so as to move toward the outside by the opening movement amount.

The opening and closing movement amount of the position detector 24L is set by the one-shot multivibrator 82L.

This opening and closing movement amount keeps the distance between the position detector 24L and the position detector 24R slightly wider than the width dimension of the strip 8 after the closing operation is completed and keeps the position detector 24L. Necessary to ensure stable and reliable tracking without hunting the width edge of the strip 8 when the position detector 24R and the position detector 24R move together while maintaining a predetermined fixed interval (during parallel operation). It is said that.

In contrast to the above 60L to 82L and the like, the specifications and purposes of 60R to 82R and the like in the figure are exactly the same.

The NAND circuit 84, when the position detector 24L and the position detector 24R are simultaneously at the high level,
That is, when they are located inside the width edge of the strip 8 at the same time, further closing operation is prevented, and at this time, the output of the NAND circuit 84 is at a low level. Therefore, the gate of the AND circuit 80L is closed, the input signals to the closed side input terminals C of the motor drive circuit 70L and the motor drive circuit 70R are cut off, the motors 28L and 28R are not driven, and the position detector 24L and 24R do not move.

The NOR circuit 86 having four input terminals is
When the position detector 24L or the position detector 24R is performing a closing operation or an inching operation, it outputs a low level signal to close the gates of the AND circuits 88L and 88R. is doing.

The AND circuit 88L has an open side input terminal O of the motor drive circuit 70L when its gate is opened.
The same signal applied to the OR circuits 78R and A
The other motor drive circuit 70 via the ND circuit 80R
It acts to apply the voltage to the closed side input terminal C of R.

Further, the AND circuit 88R outputs the same signal as the signal applied to the open side input terminal O of the motor drive circuit 70R when the gate of the AND circuit 88R is opened via the OR circuit 78L and the AND circuit 80L. Of the motor drive circuit 70L.

At this time, the position detectors 24L and 24R
Are moved in the same direction and at the same speed (parallel operation).

This parallel operation is performed after the closing operation and the inching operation are completed, that is, the flip-flop circuits 74L and 74L.
R is reset and becomes a low level output signal, and AND
The gates of the circuits 76L and 76R are closed to form a low-level output signal, the gates of the OR circuits 78L and 78R are opened, and the position detector 24L or 24R is used.
Only one of them is located inside the width edge of the strip 8 and outputs a high level signal, the output of the NAND circuit 84 becomes high level, and the gates of the AND circuits 80L and 80R are opened. It is carried out when it is in a state where it is in the open state.

In this parallel operation, when the position detector 24L detects the left width edge portion of the strip 8 and moves it to the left in an attempt to move outward from the left width edge portion, the position detector 24R is also the same. The position detector 24R senses the right width edge of the strip 8 as a result of the movement to follow the left direction at a speed, and conversely, the position detector 24R detects that the right width edge moves outward from the right width edge. The position detector 24L is also required to be moved to follow the right direction at the same speed when being moved to.

That is, the position detector 24L and the position detector 24
It is considered that they can move to the left and right while the distance between them and R is kept constant.

The operation of the lateral deviation amount detecting device thus configured will be described step by step.

1. At a required period or when the width of the strip 8 changes, a closing operation start command automatically applied to the input terminal 72 from the outside causes a position detector 24L and a position detector 24L located at a position farther than both width edges of the strip 8. 24
The Rs each start to move towards the width edges separately. (Close operation)

2. When the position detector 24L or 24R reaches the width edge portion of the strip 8 and detects the width edge portion, the position detector 24L or 24R temporarily stops and then starts moving in the opposite direction. (Opening motion)

3. It moves toward the outside of the width edge portion by the required opening movement amount and stops.

4. When the strip 8 laterally shifts to the left, the position detector 24L follows it and moves to the left so as to be driven by the left width edge of the strip 8.
At this time, the position detector 24R moves in the same speed and in the same direction as the position detector 24L, and both of them constantly maintain a constant interval. That is, the position detector 24R always follows the left edge portion of the strip 8. (Parallel operation) On the contrary, if the strip 8 laterally shifts to the right, everything moves in the opposite direction as described above.

5. By moving the position detectors 24L and 24R, the slide base 26C is mechanically differentially moved, and is moved by a difference in the amount of movement thereof (the left and right directions are distinguished by symbols). (Differential operation)

6. The movement amount of the slide table 26C is detected by the movement amount detector 42, and is output as the lateral deviation amount.

7. When the width of the strip 8 changes and becomes wider, the position detectors 24L and 24R automatically start moving toward both width edges of the strip 8. (Opening motion)

8. Each of the position detectors 24L or 24R stops at the moment when it reaches the width edge of the strip 8 and detects the width edge.

9. Same as item 3 above.

As has been clarified in the above description, this lateral deviation amount detecting device operates reliably, and in the embodiment,
The lateral deviation detection accuracy of this was within an error range of ± 1 mm and was extremely good.

In the lateral deviation amount detecting apparatus according to the present embodiment, since a laser beam having a small projected spot diameter and a large energy density is applied to the position detector, an extremely clear optical contrast is obtained unlike the image sensor. Therefore, it has an overwhelming advantage in detection accuracy and stability.

In the above embodiment, the present invention is
Although it has been applied to the detection of the amount of lateral deviation of a thin steel plate (strip) of a hot dip galvanizing device from a reference position to be traveled, the scope of application of the present invention is not limited to this, and lateral deviation of other devices and other belt-shaped materials Obviously, it can also be applied to the detection of quantity.

[0102]

According to the present invention, it is possible to accurately and easily detect the amount of lateral deviation of the strip from the reference position where the strip should run even in a bad environment such as a hot dip galvanizing apparatus. Have.

Therefore, for example, by controlling the meandering of the strip by using the output signal of the strip lateral deviation amount detecting device of the present invention, it is possible to use a sink roll having no groove, thereby producing a high quality plated plate. I was able to do it.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a plating apparatus used in a hot-dip galvanizing line.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a perspective view showing an external appearance (partly inside) of an embodiment of a lateral deviation amount detection device according to the present invention.

FIG. 4 is a perspective view showing a structure of a detection unit body of the lateral deviation amount detection device.

FIG. 5 is a circuit diagram showing an outline of a controller also used in the lateral deviation amount detection device.

[Explanation of symbols]

 8 ... Strip-shaped material (strip) 14 ... Wiping nozzle 18 ... Alloying furnace 22 ... Detection part main body 24L, 24R ... Left and right position detection device 26L, 26R, 26C ... Sliding base 28L, 28R ... Motor 30L, 30R ... Drive Wheels 40L, 40R ... Transmission band 42 ... Movement amount detector 44 ... Case

Claims (2)

[Claims] 1. A strip lateral deviation amount detecting device for detecting a lateral deviation amount of a traveling strip from a reference position, and left and right position detecting means for respectively detecting left and right width edges of the strip. A left and right moving means for loading the left and right position detecting means respectively and moving in the width direction of the strip, a drive source for the left and right moving means, and the left and right moving means, Left and right transmitting means for transmitting the driving force of the drive source respectively, and differential means for interlocking with the movements of the left and right transmitting means and differential according to the movement of the left and right moving means, Knowing the amount of movement of the differential means, a detection unit main body including a movement amount detection means for outputting this as a lateral deviation amount, and receiving and processing output signals from the left and right position detection means, Left and right position detection The left and right positions of the strip, and the left and right position detecting means are interlocked with each other, and the left and right position detecting means are interlocked with each other. After the detecting means is automatically set to the vicinity of both width edges of the strip respectively, the both width edges of the strip are moved so as to integrally follow the width edges, and the left and right movements are performed. A lateral displacement amount detecting device for a strip, wherein the lateral displacement amount of the strip is detected by reading and outputting the amount of displacement of the differential device, which is moved according to the means, by the displacement amount detecting device. 2. The apparatus according to claim 1, wherein the detection unit main body and the control means are integrally housed in a case for protecting them from the ambient atmosphere and installed between the wiping nozzle of the plating apparatus and the alloying furnace. Characteristic strip lateral deviation amount detection device.