JP3407875B2 - Electromagnet for non-contact control of thin steel plates - Google Patents
Electromagnet for non-contact control of thin steel platesInfo
- Publication number
- JP3407875B2 JP3407875B2 JP2000012625A JP2000012625A JP3407875B2 JP 3407875 B2 JP3407875 B2 JP 3407875B2 JP 2000012625 A JP2000012625 A JP 2000012625A JP 2000012625 A JP2000012625 A JP 2000012625A JP 3407875 B2 JP3407875 B2 JP 3407875B2
- Authority
- JP
- Japan
- Prior art keywords
- thin steel
- magnetic pole
- electromagnet
- steel plate
- control
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
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- Straightening Metal Sheet-Like Bodies (AREA)
Description
【発明の詳細な説明】
【０００１】
【発明の属する技術分野】本発明は、製鉄設備の圧延ラ
イン、表面処理ライン等において薄鋼板の振動制御装置
・Ｃ反り矯正装置等に用いられる、薄鋼板非接触制御用
電磁石に関するものである。
【０００２】
【従来の技術】従来、電磁石を用いた強磁性体制御に関
する非接触制御技術として、特開平５−２４５５２１号
公報や特開平２−６２３５５号公報などに記載されるも
のがある。これらの技術は、非接触センサで制御対象
（薄鋼板）の位置を検知し、制御対象から所要の間隔を
あけて制御対象の片側もしくは両側に配置した電磁石に
よって、制御対象に対して吸引力を与え、鋼板のＣ反り
等の形状不良を矯正したり、鋼板の振動を抑制したりす
るものである。従来、これらの目的で用いられる電磁石
の設計は、求められる制御特性や装置の空間的制約に応
じて、全体の形状を決定してきた。
【０００３】
【発明が解決しようとする課題】図３に薄鋼板のＣ反り
を制御するための電磁石の配置の例を示す。図に示すよ
うに、鋼板１１の幅方向に電磁石１２、１３、１４を３
個以上配置する。このとき、一つの電磁石に注目する
と、電磁石によって発生する吸引力は薄鋼板に対して１
点で作用することが好ましいが、実際には複数点で作用
する。つまり、電磁石の磁極発生面（本明細書において
「磁極発生面」とは、磁極が生じる面のことをいう。）
から吸引力が生成されるため、この磁極発生面の数だけ
吸引力が発生する。
【０００４】よって、図４に示すように磁極発生面１２
ａ、１２ｂ、１３ａ、１３ｂ、１４ａ、１４ｂが板幅方
向に並んでいる場合、Ｃ反りによって各磁極と薄鋼板１
１との距離が異なってしまい、各磁極が発生する吸引力
が異なってしまう（図においては、各磁極発生面の吸引
力の大きさを矢印で表しているが、図に示すように、磁
極発生面１２ａと１２ｂ、１４ａと１４ｂの吸引力が異
なってしまう）。Ｃ反り矯正制御では、各電磁石が板幅
方向に１点で吸引力を作用させていると見なしているの
で、上記のように一つの電磁石が複数の吸引力を、しか
も異なる大きさで作用させている場合、制御不能に陥る
か、制御能力を大きく低下させてしまう。
【０００５】また、各磁極発生面内の磁束分布に注目す
ると磁束同士は反発しあって存在している。それゆえ、
磁極発生面が長方形であるとすると、図５に示すように
４隅に磁束が集まるように分布する。すなわち、吸引力
も４隅に集中する。磁極発生面が板幅方向に幅広である
場合、各磁極が発生する吸引力も板幅方向に複数発生す
る。Ｃ反りによって磁極発生面に対して鋼板が傾いてい
るので、同一の磁極発生面では本来均一であるはずの吸
引力が異なってしまう。Ｃ反り矯正制御では、各電磁石
が板幅方向に１点で吸引力を作用させていると見なして
いるので、このような場合、制御不能に陥るか、制御能
力を大きく低下させる。
【０００６】このような問題点は、振動制御の場合に
も、Ｃ反り矯正の場合と同様に発生する。薄鋼板の振動
制御で、薄鋼板の長手方向の弦振動だけを問題にするな
ら、電磁石の磁極の並び方、すなわち各磁極で発生する
吸引力の並び方は板幅方向とすることが望ましい。しか
しながら、実際には、図６(a)に示すように、薄鋼板の
ねじり振動モードが問題になることがほとんどであり、
このような場合、薄鋼板と電磁石との位置関係・吸引力
の考え方は、断面図(b)に示されるように、Ｃ反りの場
合と同じになり、前記と同じような問題が生じる。
【０００７】本発明はこのような問題点を解決するため
になされたものであり、Ｃ反り矯正やねじり振動を抑制
する場合においても有効に作用する薄鋼板非接触制御用
電磁石を提供することを課題とする。
【０００８】
【課題を解決するための手段】前記課題は、磁極発生面
が薄鋼板の長手方向に並ぶように配設され、磁極発生面
の薄鋼板長手方向の一辺の長さをＷａ、板幅方向の一辺
の長さをＷｂとした時、Ｗａ≧Ｗｂとされていることを
特徴とする薄鋼板非接触制御用電磁石（請求項１）によ
り解決される。
【０００９】本手段においては、Ｃ反りやねじり振動が
発生した場合においても、一つの磁石においては、磁極
発生面と薄鋼板との距離は、複数の磁極発生面について
略同一に保たれる。よって、各磁極発生面からの吸引力
は略等しくなるので、板幅方向については、一つの電磁
石が１点で力を作用させているとみなすことができる。
よって、従来の方法で制御を行なっても、良好な制御特
性を得ることができる。
【００１０】
【００１１】磁極発生面が薄鋼板の長手方向に並ぶよう
に配設した電磁石の磁極発生面において、薄鋼板長手方
向の一辺の長さをＷａ、板幅方向の一辺の長さをＷｂと
する。磁極発生面内における磁束が板幅方向に分布を持
たないようにするには、板幅方向の辺の長さＷｂを小さ
くすれば良い。しかしながら、電磁石による吸引力は磁
極発生面の面積すなわちＷａ×Ｗｂに比例するため、吸
引力を一定量確保する為にＷａを大きくしなければなら
ない。以上より、Ｗａ≧Ｗｂとなるように磁極発生面す
なわち電磁石コアを設計することにより、吸引力を低下
させずに、いた幅方向について一つの磁極発生面から発
生する吸引力を均一にすることができ、従来の方法で制
御を行なっても、良好な制御特性を得ることができる。
【００１２】
【発明の実施の形態】以下、本発明の実施の形態の例を
図を用いて説明する。図１は、本発明の実施の形態の１
例を示す図であり、薄鋼板の上下に電磁石を設けた例を
示すものである。(a)は平面図、(b)は正面図である。図
１において、１は薄鋼板、２は電磁石、２ａ、２ｂは磁
極発生面、３は電磁石、３ａ、３ｂは磁極発生面、４は
薄鋼板位置センサ（距離計）である。
【００１３】薄鋼板１を挟んで、上下の対向する位置に
は、電磁石２、３が設けられている。これら電磁石は、
薄鋼板の幅方向に複数組（少なくとも３組）設けられて
いる。図示しない制御装置は、位置センサ４によって測
定された薄鋼板１の幅方向所定位置における上下方向位
置変動に応じて、薄鋼板１のＣ反りや振動を検出し、こ
れらを抑制するように各電磁石２、３の励磁電流を制御
する。
【００１４】この実施の形態においては、各電磁石２、
３の磁極発生面２ａと２ｂ、３ａと３ｂが、互いに薄鋼
板１の長手方向に配設されている。よって、Ｃ反りやね
じり振動が発生した場合でも、一つの電磁石２において
は、磁極発生面２ａと薄鋼板１間の距離は磁極発生面２
ｂと薄鋼板１間の距離と同一に保たれる。同じことは、
一つの電磁石３においても言える。よって、制御におい
て、一つの電磁石については、位置センサ４で測定され
た距離から、各磁極発生面の距離を算出し、それが同一
であるとして制御を行なっても問題は発生しない。図１
においては、コ字型コイルを使用しているが、Ｅ型コイ
ルを使用した場合でも事情は同じであり、このことは当
業者には説明を要しないであろう。
【００１５】図２は、本発明に用いられるコ字型コイル
(a)とＥ型コイル(b)の例を示した図であり、(a)、(b)に
ついて、それぞれ平面図と正面図を示したものである。
各々において、磁極発生面の薄鋼板長手方向の一辺の長
さをＷａ、板幅方向の一辺の長さをＷｂとしたとき、Ｗ
ａ≧Ｗｂとなるようにしている。
【００１６】このようにすることにより、前述のよう
に、吸引力を低下させること無く、磁極発生面の板幅方
向の一辺の長さを小さくすることができるので、Ｃ反り
やねじり振動が発生した場合でも、一つの磁極発生面に
おける吸引力発生位置と薄鋼板間の距離は、略同一に保
たれる。よって、制御において、一つの電磁石について
は、位置センサで測定された距離から、各磁極発生面の
距離を算出し、それが同一であるとして制御を行なって
も問題は発生しない。
【００１７】
【発明の効果】以上説明したように、本発明によれば、
薄鋼板のＣ反りが大きかったり、ねじれ振動モードが発
生しても、一つの電磁石からの吸引力が板幅方向で変わ
ることがないので、安定に非接触制御を行うことができ
る。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin steel sheet used for a steel sheet vibration control device, a C warpage correction device, etc. in a rolling line, a surface treatment line, etc. of an iron making facility. The present invention relates to a non-contact control electromagnet. 2. Description of the Related Art Conventionally, non-contact control techniques related to ferromagnetic control using an electromagnet are described in Japanese Patent Application Laid-Open Nos. 5-245521 and 2-62355. These technologies use a non-contact sensor to detect the position of the control target (thin steel plate) and apply an attractive force to the control target by electromagnets placed on one or both sides of the control target at a required interval from the control target. This is to correct shape defects such as C warpage of the steel sheet and to suppress vibration of the steel sheet. Conventionally, the design of an electromagnet used for these purposes has determined the overall shape according to the required control characteristics and the spatial constraints of the device. FIG. 3 shows an example of an arrangement of electromagnets for controlling the C warpage of a thin steel plate. As shown in the figure, the electromagnets 12, 13, 14 are arranged in the width direction of the steel plate 11 by three.
More than one. Attention is paid to one electromagnet at this time.
It preferably acts at points, but actually acts at multiple points. That is, the magnetic pole generating surface of the electromagnet (in the present specification, the “magnetic pole generating surface” refers to a surface on which magnetic poles are generated.)
, An attraction force is generated by the number of the magnetic pole generating surfaces. [0004] Therefore, as shown in FIG.
When a, 12b, 13a, 13b, 14a, and 14b are arranged in the plate width direction, each magnetic pole and the thin steel plate 1
1 and the attractive force generated by each magnetic pole is different (in the figure, the magnitude of the attractive force of each magnetic pole generating surface is indicated by an arrow. The suction forces of the generating surfaces 12a and 12b and 14a and 14b are different). In the C warpage correction control, since it is considered that each electromagnet exerts an attractive force at one point in the plate width direction, as described above, one electromagnet applies a plurality of attractive forces with different magnitudes. In such a case, control becomes impossible or the control ability is greatly reduced. [0005] When attention is paid to the magnetic flux distribution in each magnetic pole generating surface, the magnetic fluxes repel each other and exist. therefore,
Assuming that the magnetic pole generating surface is rectangular, the magnetic flux is distributed so as to gather at four corners as shown in FIG. That is, the suction force also concentrates on the four corners. When the magnetic pole generation surface is wide in the plate width direction, a plurality of attractive forces generated by each magnetic pole are also generated in the plate width direction. Since the steel sheet is inclined with respect to the magnetic pole generating surface due to the C warpage, the attractive force that should be uniform on the same magnetic pole generating surface differs. In the C warpage correction control, it is assumed that each electromagnet exerts an attractive force at one point in the plate width direction. In such a case, control becomes impossible or the control ability is greatly reduced. [0006] Such a problem also occurs in the case of vibration control as in the case of C warpage correction. If only string vibration in the longitudinal direction of the thin steel sheet is considered as a problem in the vibration control of the thin steel sheet, it is desirable that the arrangement of the magnetic poles of the electromagnet, that is, the arrangement of the attraction generated in each magnetic pole be in the width direction of the sheet. However, in practice, as shown in FIG. 6 (a), the torsional vibration mode of a thin steel plate often becomes a problem,
In such a case, the concept of the positional relationship / attractive force between the thin steel plate and the electromagnet becomes the same as in the case of C warpage as shown in the cross-sectional view (b), and the same problem as described above occurs. The present invention has been made in order to solve such problems, and an object of the present invention is to provide a thin steel sheet non-contact control electromagnet which works effectively even when correcting C warpage and suppressing torsional vibration. Make it an issue. [0008] The above object is achieved by a magnetic pole generating surface.
Are arranged in the longitudinal direction of the thin steel plate, and the magnetic pole generation surface
The length of one side in the longitudinal direction of the thin steel sheet is Wa, and one side in the sheet width direction
When the length of Wb is Wb, Wa ≧ Wb is satisfied.
According to the characteristic electromagnet for non-contact control of a thin steel sheet (Claim 1)
Is resolved. In this means, even when C warpage or torsional vibration occurs, in one magnet, the distance between the magnetic pole generating surface and the thin steel plate is kept substantially the same for a plurality of magnetic pole generating surfaces. Therefore, since the attraction force from each magnetic pole generating surface is substantially equal, it can be considered that one electromagnet exerts a force at one point in the plate width direction.
Therefore, good control characteristics can be obtained even if control is performed by a conventional method. In the magnetic pole generating surface of the electromagnet arranged so that the magnetic pole generating surfaces are arranged in the longitudinal direction of the thin steel sheet, the length of one side in the longitudinal direction of the thin steel sheet is Wa, and the length of one side in the sheet width direction is Wa. Wb. In order to prevent the magnetic flux in the magnetic pole generating surface from having a distribution in the plate width direction, the length Wb of the side in the plate width direction may be reduced. However, since the attractive force of the electromagnet is proportional to the area of the magnetic pole generating surface, that is, Wa × Wb, it is necessary to increase Wa in order to secure a constant amount of the attractive force. As described above, by designing the magnetic pole generating surface, that is, the electromagnet core, so that Wa ≧ Wb, it is possible to make the attractive force generated from one magnetic pole generating surface uniform in the width direction without reducing the attractive force. Thus, good control characteristics can be obtained even if control is performed by a conventional method. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows Embodiment 1 of the present invention.
It is a figure which shows an example, and shows the example which provided the electromagnet on the upper and lower sides of a thin steel plate. (a) is a plan view, and (b) is a front view. In FIG. 1, 1 is a thin steel plate, 2 is an electromagnet, 2a and 2b are magnetic pole generating surfaces, 3 is an electromagnet, 3a and 3b are magnetic pole generating surfaces, and 4 is a thin steel plate position sensor (distance meter). Electromagnets 2 and 3 are provided at positions vertically opposed to each other with the thin steel plate 1 interposed therebetween. These electromagnets
Plural sets (at least three sets) are provided in the width direction of the thin steel plate. The control device (not shown) detects the C-warp or vibration of the thin steel sheet 1 in accordance with the vertical position change at a predetermined position in the width direction of the thin steel sheet 1 measured by the position sensor 4, and controls each electromagnet so as to suppress these. A few exciting currents are controlled. In this embodiment, each electromagnet 2,
The three magnetic pole generating surfaces 2a and 2b, 3a and 3b are arranged in the longitudinal direction of the thin steel plate 1 with respect to each other. Therefore, even when C warpage or torsional vibration occurs, in one electromagnet 2, the distance between the magnetic pole generating surface 2a and the thin steel plate 1 is equal to the magnetic pole generating surface 2a.
The distance between b and the thin steel plate 1 is kept the same. The same is
The same can be said for one electromagnet 3. Therefore, in control, for one electromagnet, no problem occurs even if the distance between the magnetic pole generating surfaces is calculated from the distance measured by the position sensor 4 and the distance is determined to be the same. FIG.
, A U-shaped coil is used, but the situation is the same even when an E-shaped coil is used, and this will not require explanation to those skilled in the art. FIG. 2 shows a U-shaped coil used in the present invention.
It is the figure which showed the example of (a) and the E-shaped coil (b), and has shown the top view and front view about (a) and (b), respectively.
In each case, when the length of one side of the magnetic pole generating surface in the longitudinal direction of the thin steel sheet is Wa, and the length of one side in the sheet width direction is Wb, W
a ≧ Wb. By doing so, as described above, the length of one side of the magnetic pole generating surface in the plate width direction can be reduced without lowering the attractive force. Even in this case, the distance between the attractive force generating position on one magnetic pole generating surface and the thin steel plate is kept substantially the same. Therefore, in control, for one electromagnet, no problem occurs even if the distance between the respective magnetic pole generating surfaces is calculated from the distance measured by the position sensor, and the control is performed assuming that they are the same. As described above, according to the present invention,
Even if the C-warp of the thin steel plate is large or the torsional vibration mode occurs, the attractive force from one electromagnet does not change in the width direction of the plate, so that the non-contact control can be stably performed.
【図面の簡単な説明】
【図１】本発明の実施の形態の１例を示す図である。
【図２】本発明に用いられるコ字型コイルとＥ型コイル
の例を示した図である。
【図３】薄鋼板のＣ反りを制御するための電磁石の配置
の例を示す図である。
【図４】従来の電磁石の配列において、Ｃ反りが発生し
たときの、各磁極からの吸引力の変化を示す図である。
【図５】磁束発生面における磁束の分布の例を示す図で
ある。
【図６】ねじれ振動発生時における磁極発生面と薄鋼板
との距離、及び吸引力を示す図である。
【符号の説明】
１…薄鋼板
２…電磁石
２ａ、２ｂ…磁極発生面
３…電磁石
３ａ、３ｂ…磁極発生面
４…薄鋼板位置センサ（距離計）BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing an example of an embodiment of the present invention. FIG. 2 is a diagram showing an example of a U-shaped coil and an E-shaped coil used in the present invention. FIG. 3 is a diagram showing an example of an arrangement of electromagnets for controlling C warpage of a thin steel plate. FIG. 4 is a diagram showing a change in an attractive force from each magnetic pole when C warpage occurs in a conventional arrangement of electromagnets. FIG. 5 is a diagram illustrating an example of a magnetic flux distribution on a magnetic flux generating surface. FIG. 6 is a diagram illustrating a distance between a magnetic pole generating surface and a thin steel plate and a suction force when torsional vibration occurs. [Description of Signs] 1 ... Sheet steel plate 2 ... Electromagnets 2a and 2b ... Magnetic pole generating surface 3 ... Electromagnets 3a and 3b ... Magnetic pole generating surface 4 ... Sheet steel plate position sensor (distance meter)
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) B21B 39/00 - 39/34 B65H 23/188 B21D 1/00 B21B 37/00 - 37/14 C23C 2/00 - 2/40 ──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. 7 , DB name) B21B 39/00-39/34 B65H 23/188 B21D 1/00 B21B 37/00-37/14 C23C 2 / 00-2/40
Claims (1)
うに配設され、磁極発生面の薄鋼板長手方向の一辺の長
さをＷａ、板幅方向の一辺の長さをＷｂとした時、Ｗａ
≧Ｗｂとされていることを特徴とする薄鋼板非接触制御
用電磁石。 (57) [Claims 1] The magnetic pole generating surface is aligned in the longitudinal direction of the thin steel plate.
The length of one side of the magnetic pole generation surface in the longitudinal direction of the thin steel plate
Where Wa is the length and Wb is the length of one side in the plate width direction, Wa
≧ Wb, non-contact control of thin steel sheet
For electromagnets.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2000012625A JP3407875B2 (en) | 2000-01-21 | 2000-01-21 | Electromagnet for non-contact control of thin steel plates |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2000012625A JP3407875B2 (en) | 2000-01-21 | 2000-01-21 | Electromagnet for non-contact control of thin steel plates |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2001205325A JP2001205325A (en) | 2001-07-31 |
| JP3407875B2 true JP3407875B2 (en) | 2003-05-19 |
Family
ID=18540324
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2000012625A Expired - Fee Related JP3407875B2 (en) | 2000-01-21 | 2000-01-21 | Electromagnet for non-contact control of thin steel plates |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3407875B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107081344A (en) * | 2017-05-04 | 2017-08-22 | 西南石油大学 | Electromagnetic bending prevention device for thin-wall extruded metal material |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102008045743B3 (en) * | 2008-09-04 | 2010-04-08 | Ungerer GmbH & Co. KG | Method and device for improving mechanical properties of magnetically activatable materials |
| KR101798728B1 (en) * | 2015-12-14 | 2017-11-17 | 주식회사 포스코 | Apparatus and method for correcting sheet material |
| CN114171777B (en) * | 2022-02-15 | 2022-07-08 | 江苏时代新能源科技有限公司 | Coil winding equipment and coil winding method |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001162313A (en) | 1999-12-03 | 2001-06-19 | Shinko Electric Co Ltd | Steel plate damping device |
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2000
- 2000-01-21 JP JP2000012625A patent/JP3407875B2/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001162313A (en) | 1999-12-03 | 2001-06-19 | Shinko Electric Co Ltd | Steel plate damping device |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107081344A (en) * | 2017-05-04 | 2017-08-22 | 西南石油大学 | Electromagnetic bending prevention device for thin-wall extruded metal material |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2001205325A (en) | 2001-07-31 |
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