JP3025404B2 - Non-contact strip straightening apparatus and straightening method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to the non-contact straightening of strips.

[0002]

2. Description of the Related Art For example, in a production line for a galvannealed steel sheet, as shown in FIGS. 5 and 6, a steel sheet (strip) 1 is passed through a plating tank filled with molten zinc. Air is blown onto the steel sheet 1 from a wiping nozzle installed opposite to the pass line of the part where the steel sheet is pulled up from the steel sheet, and the amount of molten zinc (referred to as the basis weight) attached to the steel sheet surface is adjusted. The alloying treatment is performed by passing through an upper alloying furnace.

In this production line, a steel sheet pulled up from the inside of a plating tank is apt to be warped with respect to its widthwise axis (referred to as C warp). When such a C warpage occurs, the distance between the steel sheet and the wiping nozzle changes due to the difference in the position in the width direction. The amount of zinc varies depending on the position in the width direction, and the thickness of the plating is not uniform. Further, since the vibration is easily generated in the steel sheet by air blown from the wiping nozzle to the steel sheet, the thickness of the plating becomes uneven even by the vibration.

Therefore, this type of production line is provided with a straightening device for suppressing the warpage and vibration of the steel sheet. That is, by applying a magnetic attraction force to the steel sheet using an electromagnet and controlling the distance between the electromagnet and the steel sheet to be constant, vibration and warpage are suppressed. This type of technique is disclosed in, for example, Japanese Patent Application Laid-Open Nos. 2-277755 and 5-30148.

[0005] As shown in JP-A-2-277755 and JP-A-5-30148, in this type of equipment, three sets (a back and a front) are provided at mutually different positions in the width direction of the steel sheet. (6 sets in total) are installed. In some cases, a plurality of sets of these electromagnets are provided in the traveling direction of the steel sheet. Japanese Patent Application Laid-Open No. 2-277755 proposes to move the position of the electromagnet in the thickness direction of the steel sheet in order to reduce the burden on the electromagnet. Further, in the technique disclosed in Japanese Utility Model Laid-Open No. 5-30148, even if the width of the steel sheet passing therethrough changes greatly, it is possible to correct the C warpage.
It has been proposed to detect a plate edge position of a steel plate, move the electromagnets in the width direction according to the detected position, and control to position all electromagnets within the range of the plate width.

[0006]

However, in order to change the position of the electromagnet as disclosed in Japanese Utility Model Application Laid-Open No. 5-30148, a driving mechanism for moving the electromagnet is required, and the structure of the equipment becomes complicated. Also, it takes a relatively long time to move the electromagnet. In an actual production line, the rear end and the front end of a plurality of steel sheets with different specifications such as sheet widths are welded and connected to each other, so that the steel sheets are continuously passed through the line, so that the connected parts of the steel sheets pass When doing, the board width changes stepwise. If it takes time to move the electromagnet, the C-warp cannot be corrected for a while after the connecting portion passes, so that a quality defect occurs at that portion and the product yield decreases. In addition, since the distance (gap) between the electromagnet and the steel sheet is adjusted only at three locations in the width direction of the steel sheet using three sets of electromagnets, the portion where the electromagnet does not exist cannot be corrected in shape. Warpage and vibration cannot be sufficiently suppressed.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to increase the following speed of the straightening device to a change in the width of a steel sheet to be controlled sufficiently and to enhance the effect of suppressing the C warp and vibration of the steel sheet.

[0008]

In order to solve the above-mentioned problems, according to the present invention, a strip (1) continuously passed in a predetermined direction is sandwiched so as to sandwich the pass line. In a non-contact strip straightening device which includes an electromagnet arranged at a position adjacent to the thickness direction and straightens a strip by a magnetic attraction force of the electromagnet: a strip width detecting means (8) for detecting a strip width of a passed strip Four or more independent electromagnet means (N1 to N
8, S1 to S8) are arranged in the strip width direction of the strip over a range larger than the maximum strip width of the strip to be passed, and correction force generating means (2, 3); Correction force control means (5) for automatically determining the on / off state of each of the plurality of electromagnet means constituting the correction force generation means in accordance with the determined plate width.

Further, the inventions of claims 2, suited in a predetermined direction
The pass line of the strip (1) that is continuously passed through
Adjacent to the strip in its thickness direction so as to sandwich the strip.
Due to the magnetic attraction of the electromagnet
The non-contact strip straightening method of correcting-up, the
Four or more independent electromagnet means (N1 to N8, S1 to S8)
Area larger than the maximum width of the strip (1) to be passed
Across the width of the strip.
Is detecting the sheet width of the strip is to set all turned on an electromagnet means included in a range larger than the detected sheet width, to set all remaining electromagnet means to the OFF state, characterized in that.

The symbols shown in the parentheses indicate the reference numerals of the corresponding elements in the embodiments described later for reference, but each component of the present invention is a specific element in the embodiments. It is not limited to only.

[0011]

In the present invention, four or more independent sets of electromagnet means (N1 to N8, S1 to S8) are arranged side by side in the width direction of the strip.
Automatically determines the on / off state of each of the plurality of electromagnets constituting the correcting force generating means according to the sheet width detected by the sheet width detecting means. The electromagnet means is installed over a range larger than the maximum width of the strip to be passed.

Therefore, when straightening a strip having a small width or straightening a strip having a large width, the electromagnet means always faces the strip over the entire width of the strip, so that the electromagnet means does not need to be moved. The strip can be straightened over its entire width simply by energizing the electromagnet means present at the position where the straightening is required. For a strip having a small plate width, unnecessary power consumption can be suppressed by turning off the electromagnet means located at a position where there is no need to generate a magnetic attraction force.

[0013] The invention of claim 2, any electromagnetic means included in the larger range than test out the plate width is set to ON state, and sets all remaining electromagnet means to the OFF state.

Computer simulation was performed on a model in which the electromagnet and the steel plate were configured and arranged as shown in FIG. 7, and the result shown in FIG. 8 was obtained. According to this, it can be seen that the magnetic flux generated by the electromagnet disposed slightly outside the width direction edge of the steel sheet generates Maxwell stress Fxt in the direction in which the steel sheet goes outward in the width direction. This force Fxt increases particularly when the two electromagnets on the front and back sides of the steel plate are excited to the same pole (N pole-N pole or S pole-S pole). Therefore, if all of the electromagnet means included in the range larger than the plate width of the strip are excited as in claim 2, the outward force acts on both end portions in the width direction of the strip, so that the strip acts on the strip. Is applied with a tension in the width direction. By applying tension to the strip, the effect of correcting a shape defect such as C warpage of the strip is enhanced.

[0015]

EXAMPLE An example in which the present invention is applied to a production line for a galvannealed steel sheet will be described. In this production line, as shown in FIGS. 5 and 6, the steel sheet 1 is passed through a plating tank filled with molten zinc, and the wiping is installed opposite to a pass line at a portion where the steel sheet 1 is pulled up from the plating tank. Air is blown from a nozzle onto the steel sheet 1 to adjust the amount of molten zinc adhering to the surface of the steel sheet (referred to as the basis weight), and then the steel sheet is passed through an alloying furnace (not shown) located above to cause alloying. A chemical treatment is performed.

Slightly above the wiping nozzle, the electromagnet units 2 and 3 of the strip straightening device are installed so as to face each other with the steel plate 1 interposed therebetween. FIG. 1 schematically shows the configuration of the strip straightening device. FIG. 1 is a sectional view taken along the line II of FIG.
It shows a cross section as seen from the line. Referring to FIG. 1, the electromagnet unit 2 includes eight electromagnets N1, N2, N3, N4, N5, N5 arranged in a line in the width direction of the steel plate 1.
6, N7 and N8. The electromagnet units 3 are also arranged in a row in the width direction of the steel plate 1.
Electromagnets S1, S2, S3, S4, S5, S6, S7
And S8. Electromagnets N1, N2, N3
N4, N5, N6, N7 and N8 each have a built-in gap sensor 4. The gap sensor 4 detects the size of a gap between each of the electromagnets N1 to N8 and the surface of the steel plate 1. In addition, a plate width meter 8 is provided above the electromagnet unit 3. This width gauge 8 is CC
It is configured using a D image sensor, and optically detects both end positions in the width direction of the steel sheet 1 and measures the width of the steel sheet 1.

In some cases, the strip width is directly measured online using the strip width meter 8 as in this embodiment, but in the first place, each operating condition is known in advance, and the strip width currently in operation is determined in advance. Since the upper-level computer has grasped, it is possible to use this higher-level computer as an off-line board width detecting means and read the board width data grasped by the computer to detect the board width. Good.

In this embodiment, eight electromagnets N1, N
The length L0 from one end to the other end of the electromagnet unit 2 composed of 2, N3, N4, N5, N6, N7 and N8 is
The predetermined maximum width L1 of the steel sheet 1 passing through this equipment
It is larger than the width of about one electromagnet.
The length from one end to the other end of the electromagnet unit 3 is also L0, and the electromagnets S1, S2, S3, S4, S5, S6, S7
And S8 are installed in the electromagnets N1,
It is located at the same position as N2, N3, N4, N5, N6, N7 and N8.

The electromagnets N1 to N8 of the electromagnet unit 2 and the electromagnets S1 to S8 of the electromagnet unit 3 are connected to the control unit 5 via signal lines SG1, respectively, so that their energized states are individually controlled. It is configured.
Also, the gap sensor 4 built in the electromagnets N1 to N8
Are connected to the control unit 5 via signal lines SG2, respectively, and the width gauge 8 installed on the electromagnet unit 3 is connected to the control unit 5 via signal lines SG3.

FIG. 2 shows a longitudinal sectional view of the electromagnet units 2 and 3 shown in FIG. Referring to FIG. 2, the electromagnets N1, S
1 comprises an iron core 6 and an electric coil 7 wound therearound. In this example, the electric coil 7 is wound around an axis parallel to the Y axis in the figure. The electromagnet N
A gap sensor 4 is built in a central portion of the iron core 1 facing the steel plate 1. The other electromagnets N2 to N8 have the same configuration as N1, respectively, and the electromagnets S2 to S8 are S
1 has the same configuration.

FIG. 9 shows the configuration of a circuit for controlling the energization of one of the electromagnets included in the electromagnet unit 2 of FIG. 1, and FIG. 10 shows the configuration of the circuit for controlling the energization of one of the electromagnets included in the electromagnet unit 3. Show. Each of these circuits has the same number as the number of electromagnets, and is included in the control unit 5 shown in FIG.

First, a description will be given with reference to FIG. Signal line SG
A current flowing through each of the electric coils 7 of the electromagnet unit 2 through 1 is supplied from a DC power supply and controlled by a chopper 15. The current detector 20 detects the level of the current actually flowing through the signal line SG1. The signal SG4 output from the current detector 20 (analog voltage proportional to the current) is input to the signal processing circuit 16 of the control circuit 10. Further, a signal (an analog voltage proportional to the gap size) SG2 output from the gap sensor 4 provided in the electromagnet to be controlled is also input to the signal processing circuit 16. The signal processing circuit 16 includes a waveform shaping circuit, an A / D converter, and the like, sequentially samples the voltages of the input signals SG2 and SG4, and outputs numerical values corresponding to the voltages. Signal SG
2B and SG4B are digital values (detection values) corresponding to the signals SG2 and SG4, respectively.

[0023] In the subtraction unit 61, the target value Go of the gap, which is held in advance register 12, a value obtained by subtracting from the detected value SG2B, is output as a gap error x _1. The subtraction unit 62, from the most recent gap deviation x _1, the output value of the delay section (the gap deviation obtained one cycle before calculation period x ₁₎
, The time derivative dx _{1 of the} gap deviation obtained by subtracting
/ Dt is output. Subtraction unit 63, the target value Is is a current held in advance register 12, a value obtained by subtracting from the detected value SG4B, outputs a current deviation i _1. Adder 64
Outputs the result of adding the latest gap deviation x ₁ to its own output value obtained one cycle before the calculation cycle, that is, the integrated value ∫x ₁ dt of the gap deviation x ₁ . Multiplying unit 65 the result of multiplying the gain coefficient K ₄ which is held in the register 13 to the gap deviation x _1, i.e. outputs a component proportional to the gap deviation x _1, the multiplication unit 66 to the register 13 to the differential value of the gap deviation The result of multiplying the held gain coefficient K _3, that is, the differential component of the gap deviation, is output. The multiplication unit 67 multiplies the current deviation i ₁ by the gain coefficient K ₂ stored in the register 13, that is, the current deviation i outputs component proportional to _1, the multiplication unit 68 is the result of multiplying the gain coefficient K ₁ which is held in the register 13 to the gap deviation integrated value, i.e., outputs an integral component in the gap deviation.

As for the gain coefficients K ₁ , K ₂ , K ₃ and K ₄ , respective optimum values are previously calculated for each sheet thickness of the steel sheet using a computer (not shown) based on modern control theory. The gain coefficients K ₁ , K ₂ , K ₃ and K ₄ obtained for each sheet thickness obtained as a result are registered in an address corresponding to the sheet thickness in the memory 11 before the control circuit 10 operates. Have been. When the control circuit 10 operates, one set of addresses in the memory 11 is selected according to the actual thickness d of the steel sheet 1 being passed at that time, and one set of gain coefficients K ₁ , K ₂ , K ₃ and K ₄ are read out, and these information are held in the register 13.

The adder 69 includes a gap deviation proportional value output from the multiplier 65, a gap deviation differential value output from the multiplier 66, a current deviation proportional value output from the multiplier 67, and a multiplier 6.
8 and the current target value is output from the register 12 are all added, and the result is generated as a command voltage e0. This command voltage e0 is input to the chopper 15.

FIG. 11 shows the structure of the chopper 15. FIG.
1, the chopper 15 includes an amplifier 111, a triangular wave generator 112, an analog comparator 113, a gate driver 114, a switching transistor 115, and a DC power supply 1
16 and a diode 117. The triangular wave generator 112 has a triangular wave signal voltage e2 having a constant frequency and amplitude.
Is output. The analog comparator 113 compares the voltage e1 obtained by amplifying the command voltage e0 with the triangular wave voltage e2 output from the triangular wave generator 112. When e1> e2, the output signal e3 becomes high level H (on level), When e1 <e2, the output signal e3 becomes low level L (off level). Therefore, the signal e3 becomes a pulse signal, and the ratio of the ON time of the pulse, that is, the duty ratio is proportional to the command voltage e0. The transistor 115 is turned on / off according to the on / off of the signal e3. When the transistor 115 is turned on, a current flows from the DC power supply 116 to the coil 7 of the electromagnet. When the transistor 115 is turned off, the current of the coil 7 is cut off. That is, the average current flowing through the coil 7 is proportional to the command voltage e0.

Next, a description will be given with reference to FIG. Signal line S
The current flowing to each electric coil 7 of the electromagnet unit 3 through G1 is supplied from a DC power supply and controlled by the chopper 15. The current detector 20 detects the level of the current actually flowing through the signal line SG1. The signal SG4 output from the current detector 20 is output to the signal processing circuit 16 of the control circuit 10B.
Is input to The signal SG2 output from the gap sensor 4 provided in the electromagnet to be controlled is also output from the signal processing circuit 16.
Is input to As in the case of the control circuit in FIG. 9, the signal processing circuit 16 outputs digital values (detection values) corresponding to the signals SG2 and SG4 as signals SG2B and SG4B. Further, subtracting unit 61 outputs a gap deviation x _1, time subtraction portion 62 gap deviation differential value dx ₁ / d
t, the subtractor 63 outputs a current deviation i ₁ , and the adder 64 outputs an integral value ∫x ₁ dt of the gap deviation x ₁ .

The multipliers 65, 66, 67 and 68 respectively include a component proportional to the gap deviation x ₁ obtained by multiplying the gain coefficients K ₄ , K ₃ , K ₂ and K ₁ , a differential component of the gap deviation, and a current. component proportional to the deviation i _1, and outputs the integral component of the gap deviation. The gain coefficients K ₁ , K ₂ , K ₃ and K ₄ use the same values as K ₁ , K ₂ , K ₃ and K ₄ used in the circuit of FIG.

The calculation unit 69B adds the current target value is output from the register 12 and the current deviation proportional value output from the multiplication unit 67, and outputs the gap deviation proportional value output from the multiplication unit 65 and the multiplication unit 66 outputs. The differential value of the gap deviation and the integral value of the gap deviation output from the multiplying unit 68 are subtracted, and the result is generated as a command voltage e0. This command voltage e0
Is input to the chopper 15.

The operation of the correction device will now be described.
In order to facilitate understanding, the following description assumes that the target value of the current is is 0. Steel plate 1 passes through the normal pass line in the portion of the electromagnet unit 2, unless occur vibrations, since deviation x ₁ in the gap values SG2B and gap reference value Go detected is zero, the command voltage e0
Is determined only by the current target value is and the detected value SG4B. If the target value of the current is is 0, no current flows through the electromagnet of the electromagnet unit 2 and the electromagnet of the electromagnet unit 3 in a stable state, so that no special force is applied to the steel plate 1.

Here, for example, when the steel sheet 1 undergoes C warpage and the steel sheet 1 approaches the electromagnet unit 3 from the reference position at the position of the electromagnet to be controlled, the gap detection value SG2B increases. ₁ is a positive value.
In that case, a value corresponding to the gap deviation x ₁ is the command voltage e0
However, the control circuit 10 shown in FIG.
0 becomes positive, and the command voltage e0 becomes negative in the control circuit 10b of FIG. Therefore, the chopper 15 of the control circuit 10 outputs a current corresponding to e0 to the one of the electromagnet unit 2.
And the chopper 15 of the control circuit 10B
Since 0 is negative, no current flows through the coil of the electromagnet unit 3. Therefore, the steel plate 1 moves in the direction approaching the electromagnet unit 2 by the magnetic attraction generated by the electromagnet of the electromagnet unit 2. Then, as the steel sheet 1 approaches the reference position on the pass line, the gap deviation x ₁ decreases, the magnetic attraction decreases, and the gap deviation x ₁
Becomes zero, the state becomes stable.

[0032] Conversely, at the position of the electromagnet of the control target, the steel plate 1 than the reference position approaches the electromagnet unit 2, the detection value SG2B gap is reduced, the gap deviation x ₁
Becomes a negative value. In this case, a value corresponding to the gap deviation x ₁ appears as the command voltage e0, but the command voltage e0 is negative in the control circuit 10 of FIG. 9 and the command voltage e0 is positive in the control circuit 10b of FIG. Therefore, the chopper 15 of the control circuit 10b passes a current corresponding to e0 to one coil of the electromagnet unit 3, and the chopper 15 of the control circuit 10 does not pass a current to the coil of the electromagnet unit 2 because e0 is negative. . Therefore, by the magnetic attraction generated by the electromagnet of the electromagnet unit 3,
The steel plate 1 moves in a direction approaching the electromagnet unit 3. Then, as the steel plate 1 approaches the reference position on the pass line, the gap deviation x ₁ becomes smaller, the magnetic attraction decreases, and when the gap deviation x ₁ becomes 0, a stable state is established.

In practice, when the electromagnet is turned on, a positive value is set as the target value of the current is. Therefore, even when the gap deviation x ₁ is 0, the command voltage e0 of the control circuit 10B shown in control circuit 10 and 10 shown in FIG. 9, both a plus value. That is, electromagnets (for example, N1 and S1) opposed to each other across the steel plate 1
Generate magnetic flux at the same time. The reason for this control is:
This is for applying a tension to the steel plate 1 in the width direction. That is, by simultaneously energizing the electromagnet on the front side and the electromagnet on the back side of the steel sheet 1, a force in the width direction is applied to both ends in the width direction of the steel sheet 1, thereby generating tension. This tension is very effective in suppressing C warpage and vibration of the steel sheet 1.

As a result of performing a computer simulation on a model in which the electromagnets and the steel plates were configured and arranged as shown in FIG. 7, the results shown in FIG. 8 were obtained. FIG.
Shows the result of obtaining the Maxwell stress Fxt and the maximum magnetic flux density Bmax when the polarities of the magnetic poles of the opposing electromagnets are the same and different. According to this, it can be seen that the magnetic flux generated by the electromagnet disposed slightly outside the width direction edge of the steel sheet generates Maxwell stress Fxt in the direction in which the steel sheet goes outward in the width direction. This force Fxt is, in particular, 2 between the front side and the back side of the steel sheet.
It becomes large when two electromagnets are excited to the same pole (N pole-N pole or S pole-S pole). Therefore, in the apparatus shown in FIG. 1 as well, the winding direction of the coil and the direction of the current flowing therethrough are such that the magnetic poles formed on the portions of the electromagnets of the electromagnet units 2 and 3 facing the steel plate 1 are all N poles. Is defined. If all the electromagnets included in the range larger than the width of the steel plate 1 are excited, forces in the outward direction act on both end portions in the width direction of the steel plate 1. Is added.

FIGS. 9 and 10 show circuits 10 and 10B for controlling one electromagnet, respectively. The control unit 5 shown in FIG. 1 includes electromagnets N1 to N8 and S1 to S8.
The control circuit 10 or 10B is provided for each of S8. In addition, these control circuits 10, 10
B is intensively controlled by one computer (not shown) built in the control unit 5.

The computer of the control unit 5 gives the plate thickness d, the current value is and the gap value Go to the control circuits 10 and 10B to control them. The thickness d is the thickness of the steel sheet 1 actually passing through the positions of the electromagnet units 2 and 3, and is obtained from an external host computer (for example, a process computer) connected to the control unit 5. Information. The gap value Go is determined based on the structure of the device (the distance between the electromagnet units 2 and 3 and the like) and the plate thickness d.
Determined sequentially. The current value is is determined by the on / off of the electromagnet to be controlled and the tension applied to the steel plate 1. When the electromagnet is turned on, a positive value corresponding to the tension and the plate thickness d is set to the current value is, and when the electromagnet is turned off, the current value is set to a negative value. When the current value is is set to a negative value having a large absolute value, the current flowing through the coil of the electromagnet becomes 0, and the electromagnet is turned off.

The computer of the control unit 5 is
16 electromagnets N1 to N8 and S according to the width direction position and width of the steel sheet 1 detected by the width meter 8
The on / off state of 1 to S8 is controlled. That is, all electromagnets necessary for correcting and damping the steel sheet 1 to be controlled are set to the ON state, and unnecessary electromagnets are set to the OFF state to suppress wasteful power consumption. For example, the width of the steel sheet 1 passing through the positions of the electromagnet units 2 and 3 is set to a predetermined maximum width L1.
At the time, as shown in FIG. 3, the electromagnets N1 to N8, S1
-S8 are set to the ON state, and when the steel sheet having a small width passes the position of the electromagnet units 2 and 3, a part of the electromagnets N1 to N8 and S1 to S8 is set to the ON state as shown in FIG. The other electromagnets are turned off. Here, the electromagnets to be set to the ON state are determined so that their entire width is larger than the width of the steel plate 1.

That is, as shown in FIG. 3 and FIG.
Among the electromagnets 1 to N8 and S1 to S8, at least a part of the electromagnets located at positions facing the steel plate 1 in the thickness direction is turned on. Although not shown, if the edge position in the width direction of the steel plate 1 coincides with any boundary position between the electromagnets N1 to N8 (or S1 to S8), the position is located outside the steel plate 1 with respect to the boundary. One electromagnet is also turned on.
All other electromagnets are turned off. This way,
As can be seen from the results of the simulations shown in FIGS. 7 and 8, a force Fxt in the widthwise outward direction acts on the edge portion of the steel sheet 1, and thus a tension in the width direction is applied to the steel sheet 1. . As a result, the effect of correcting the C warpage and suppressing the vibration is enhanced.

[0039]

As described above, according to the present invention, the electromagnet means always faces the strip over the entire width of the strip, both when straightening a narrow strip and when stripping a wide strip. Therefore, the strip can be corrected over the entire width only by energizing the electromagnet means existing at the position where the correction is required without moving the electromagnet means. For a strip having a small plate width, unnecessary power consumption can be suppressed by turning off the electromagnet means located at a position where there is no need to generate a magnetic attraction force. In addition, since it is not necessary to move the electromagnet means, the structure of the electromagnet is simplified, and the range in which the magnetic force is generated can be quickly switched in response to a change in the width of the strip. Thus, even if the plate width changes stepwise, it is possible to prevent the warpage and vibration from increasing at that position, and to minimize the occurrence of poor quality.

According to the second aspect, by exciting all of the electromagnet means included in a range larger than the plate width of the strip, outward force acts on both end portions in the width direction of the strip. Therefore, a tension in the width direction is applied to the strip. By applying tension to the strip, the effect of correcting a shape defect such as C warpage of the strip is enhanced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a straightening device according to an embodiment provided in the equipment shown in FIG.

FIG. 2 is an enlarged vertical sectional view of a part of FIG.

FIG. 3 is a plan view showing the electromagnet units 2 and 3 and the steel plate 1. FIG.

FIG. 4 is a plan view showing the electromagnet units 2 and 3 and the steel plate 1. FIG.

FIG. 5 is a front view showing a configuration of a main part of a plating facility.

FIG. 6 is a perspective view showing a part of FIG. 5;

FIG. 7 is a plan view showing a model of an electromagnet and a steel plate used in the simulation.

FIG. 8 is a graph showing a result of a simulation for the model of FIG. 7;

FIG. 9 is a block diagram showing one control circuit built in the control unit of FIG. 1;

FIG. 10 is a block diagram showing one control circuit built in the control unit of FIG. 1;

FIG. 11 is a block diagram showing a configuration of a chopper 15;

[Explanation of symbols]

1: steel plate 2, 3: electromagnet unit 4: gap sensor 5: control unit 6: iron core 7: electric coil 8: plate width meter 10, 10B: control circuit 11: memory 12, 13: register 15: chopper 16: signal processing Circuit 116: DC power supply N1 to N8, S1 to S8: electromagnet

Continuation of the front page (72) Inventor Kiyoshi Wajima 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Corporation Technology Development Division (56) References JP-A-5-32364 (JP, A) JP-A Heisei 5-245521 (JP, A) U.S. Pat. No. 3,874,072 (US, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B21D 1/00 C23C 2 / 26,2 / 40

Claims (2)

(57) [Claims] 1. An electromagnet disposed at a position adjacent to a strip in a thickness direction of the strip so as to sandwich a pass line of the strip continuously passed in a predetermined direction, and a magnetic attraction of the electromagnet. In a non-contact strip straightening device for straightening a strip by force: a strip width detecting means for detecting a strip width of a strip to be passed; four or more independent electromagnet means each having a maximum width of a strip to be passed. Correction force generating means arranged side by side in the width direction of the strip over a large range; and turning on / off each of a plurality of electromagnet means constituting the correction force generation means according to the width of the sheet detected by the width detection means. A straightening force control means for automatically determining an on / off state; 2. The sheet is continuously passed in a predetermined direction.
So that the strip pass line is sandwiched
On the other hand, the electromagnet placed at a position adjacent to the thickness direction
Non-contact strip for straightening strip by magnetic attraction
In the method of straightening a stap, four or more sets of electromagnets each independent of one another
Over a range larger than the maximum width of the lip,
Are provided side by side in the width direction of the
Detecting the plate width, then set the electromagnet means included in a range larger than the detected sheet width all turned on to set all remaining electromagnet means to the OFF state, and wherein the <br/> non Contact strip straightening method .