JP3545540B2 - Flow controller for molten metal - Google Patents

Description

となり、電流Ｉ２は、ΔＩ１・ｓｉｎ２πｆｔなるゆらぎを有するものとなる。第１実施例のコントロ−ラ１５の機能構成を図６に示す。コントロ−ラ１５は、オペレ−タが与えるＩ１０とΔＩ１の和を算出（５４）して、Ｉ１＝Ｉ１０＋ΔＩ１を表わす電流指令値ＶdcＡ１を、電源回路１１の位相角α算出器２４Ａ１に与える。また、オペレ−タが与えるゆらぎ周波数指示信号Ｖｆのレベルに比例する周波数ｆのクロックパルスを発生してそれをカウントし、すなわち計時して、正弦波ｓｉｎ２πｆｔの各時刻のレベルｓｉｎωｔ＝ｓｉｎ２πｆｔを算出（５２）し、それにΔＩ１を乗算（５３）した積ΔＩ１ｓｉｎωｔにＩ２０を加算（５５）して、和Ｉ２＝Ｉ２０＋ΔＩ１ｓｉｎωｔを表わす電流指令値ＶdcＡ２を、電源回路１２の位相角α算出器２４Ａ２（図示しないが、２４Ａ１と等価のもの）に与える。またオペレ−タが与える周波数指令Ｆ１およびＦ２を表わす周波数指令ＦdcＡ１およびＦdcＡ２を、電源回路１１および１２の３相信号発生器３１Ａ１および３１Ａ２（図示しないが、３１Ａ１と等価のもの）に与える。なお、この実施例では、Ｆ１およびＦ２は５〜５０Ｈｚの範囲内で、Ｆ１＝Ｆ２又はＦ１≒Ｆ２とする。ゆらぎ周波数ｆは、この実施例では０．５Ｈｚ又はその前後の値である。
【００３３】
電源回路１１は、周波数指令ＦdcＡ１で指定された周波数Ｆ１の、電流指令ＶdcＡ１で指定されたレベルＩ１の電流を、第１リニアモ−タ３Ｆの電気コイル５，６ならびに第２リニアモ−タ３Ｌの電気コイル７，８に通電する。電源回路１２は、周波数指令ＦdcＡ２で指定された周波数Ｆ２の、電流指令ＶdcＡ２で指定されたレベルＩ２であって、ΔＩ１ｓｉｎωｔ＝ΔＩ１ｓｉｎ２πｆｔなるゆらぎを含む電流を、第１リニアモ−タ３Ｆの電気コイル３，４ならびに第２リニアモ−タ３Ｌの電気コイル９，１０に通電する。
【００３４】
これにより、ノズル５周りの淀み域ＳＴ１およびＳＴ２に、電気コイル３，４および電気コイル９，１０が与える推力のゆらぎが加わり、淀み域ＳＴ１およびＳＴ２の溶鋼に周波数ｆのゆらぎが加わり、このゆらぎにより淀み域の溶鋼が流動域に移動する。すなわち周波数ｆで駆動されて流動し、淀み域での滞留が無くなる。
【００３５】
−第２実施例−
第２実施例は、 β＝Σβ_iｓｉｎ（ｉωｔ） −−−（７）
ω＝２π（１／ｆ）ｔ
β_i＝∝１／ｉ
１＝√（Σ┃β_i┃²）
なるパルス波のゆらぎを電流Ｉ２に与えるものであり、第２実施例ではｉ＝１〜３（整数）とした。
【００３６】
図７に、第２実施例のコントロ−ラ１５の機能構成を示す。コントロ−ラ１５は、オペレ−タが与えるＩ１０とΔＩ１の和を算出（５４）して、Ｉ１＝Ｉ１０＋ΔＩ１を表わす電流指令値ＶdcＡ１を、電源回路１１の位相角α算出器２４Ａ１に与える。また、オペレ−タが与えるゆらぎ周波数指示信号Ｖｆのレベルに反比例する周波数１／ｆのクロックパルスを発生してそれをカウントし、すなわち計時して、正弦波ｓｉｎ（２πｔ／ｆ）の各時刻のレベルｓｉｎωｔ＝ｓｉｎ（２πｔ／ｆ），正弦波ｓｉｎ（４πｔ／ｆ）の各時刻のレベルｓｉｎ２ωｔ＝ｓｉｎ（４πｔ／ｆ）、および、正弦波ｓｉｎ（６πｔ／ｆ）の各時刻のレベルｓｉｎ３ωｔ＝ｓｉｎ（６πｔ／ｆ）を算出（５２）し、それらを、（６／７），（３／７）および（２／７）の重みを付して加算（５６）した和
β＝(6/7)sin(２πｔ／ｆ)＋(3/7)sin(4πｔ／ｆ)＋(2/7)sin(６πｔ／ｆ）
にΔＩ１を乗算（５３）した積ΔＩ１・βにＩ２０を加算（５５）して、和Ｉ２＝Ｉ２０＋ΔＩ１・βを表わす電流指令値ＶdcＡ２を、電源回路１２の位相角α算出器２４Ａ２に与える。またオペレ−タが与える周波数指令Ｆ１およびＦ２を表わす周波数指令ＦdcＡ１およびＦdcＡ２を、電源回路１１および１２の３相信号発生器３１Ａ１および３１Ａ２に与える。
【００３７】
この第２実施例のコントロ−ラ１５を除く他の要素は、上述の第１実施例のものと同一であるので、ここでの説明は省略する。
【００３８】
電源回路１１は、周波数指令ＦdcＡ１で指定された周波数Ｆ１の、電流指令ＶdcＡ１で指定されたレベルＩ１の電流を、第１リニアモ−タ３Ｆの電気コイル５，６ならびに第２リニアモ−タ３Ｌの電気コイル７，８に通電する。電源回路１２は、周波数指令ＦdcＡ２で指定された周波数Ｆ２の、電流指令ＶdcＡ２で指定されたレベルＩ２であって、ΔＩ１・βなるゆらぎを含む電流を、第１リニアモ−タ３Ｆの電気コイル３，４ならびに第２リニアモ−タ３Ｌの電気コイル９，１０に通電する。
【００３９】
これにより、ノズル５周りの淀み域ＳＴ１およびＳＴ２に、電気コイル３，４および電気コイル９，１０が与える推力のゆらぎが加わり、淀み域ＳＴ１およびＳＴ２の溶鋼に周波数ｆのゆらぎが加わり、このゆらぎにより淀み域の溶鋼が流動域に移動する。すなわち周波数ｆで駆動されて流動し、淀み域での滞留が無くなる。
【００４０】
−第３実施例−
第３実施例は、上記（５）式で定義したゆらぎβを、電源回路１１が発生する３相交流の周波数Ｆ１に与えるものである。
【００４１】
図８に、第３実施例のコントロ−ラ１５の機能構成を示す。コントロ−ラ１５は、オペレ−タが与える電流指令値Ｉ１とＩ２をそれぞれ電流指令値ＶdcＡ１およびＶdcＡ２として、電源回路１１および１２の位相角α算出器２４Ａ１，２４Ａ２に与える。また、オペレ−タが与えるゆらぎ周波数指示信号Ｖｆのレベルに反比例する周波数１／ｆのクロックパルスを発生してそれをカウントし、すなわち計時して、正弦波β＝ｓｉｎωｔ＝ｓｉｎ２πｆｔを算出（５２）し、それにオペレ−タが与えるゆらぎレベルＦ０を乗算（５３）した積Ｆ０・β＝Ｆ０・ｓｉｎωｔに、電源回路１２に与えるためにオペレ−タが入力した周波数指令Ｆ２を加算（５５）して、和Ｆ１＝Ｆ２＋Ｆ０・ｓｉｎωｔを表わす周波数指令Ｆ１dcＡ１を、電源回路１１の３相信号発生器３１Ａ１に与える。コントロ−ラ１５はまた、オペレ−タが入力した周波数指令Ｆ２を、周波数指令Ｆ１dcＡ２として、電源回路１２の３相信号発生器３１Ａ２（図示せず、３１Ａ１と等価のもの）に与える。
【００４２】
この第３実施例のコントロ−ラ１５を除く他の要素は、上述の第１実施例のものと同一であるので、ここでの説明は省略する。
【００４３】
電源回路１１は、周波数指令ＦdcＡ１で指定された周波数Ｆ１の、電流指令ＶdcＡ１で指定されたレベルＩ１の電流を、第１リニアモ−タ３Ｆの電気コイル５，６ならびに第２リニアモ−タ３Ｌの電気コイル７，８に通電する。上述のようにＦ１＝Ｆ２＋Ｆ０・ｓｉｎωｔであるので、電源回路１１が電気コイル５，６ならびに７，８に与える３相交流の周波数は、Ｆ０・ｓｉｎωｔのゆらぎを生ずる。
【００４４】
電源回路１２は、周波数指令ＦdcＡ２で指定された周波数Ｆ２の、電流指令ＶdcＡ２で指定されたレベルＩ２電流を、第１リニアモ−タ３Ｆの電気コイル３，４ならびに第２リニアモ−タ３Ｌの電気コイル９，１０に通電する。
【００４５】
これにより、ノズル５周りの淀み域ＳＴ１およびＳＴ２に、５，６ならびに７，８が与える推力のゆらぎが加わり、このゆらぎにより淀み域の溶鋼が流動域に移動する。すなわちβ＝ｓｉｎωｔの正弦波状のゆらぎで駆動されて流動し、淀み域での滞留が無くなる。
【００４６】
−第４実施例−
第４実施例は、上記（７）式で定義されるゆらぎβを電源回路１１が発生する３相交流の周波数Ｆ１に与えるものである。第４実施例でも、ｉ＝１〜３（整数）とした。
【００４７】
図９に、第４実施例のコントロ−ラ１５の機能構成を示す。コントロ−ラ１５は、オペレ−タが与える電流指令Ｉ１およびＩ２を、それぞれ電流指令ＶdcＡ１およびＶdcＡ２として電源回路１１および１２の位相角α算出器２４Ａ１および２４Ａ２に与える。また、オペレ−タが与えるゆらぎ周波数指示信号Ｖｆのレベルに反比例する周波数１／ｆのクロックパルスを発生してそれをカウントし、すなわち計時して、正弦波ｓｉｎ（２πｔ／ｆ）の各時刻のレベルｓｉｎωｔ＝ｓｉｎ（２πｔ／ｆ），正弦波ｓｉｎ（４πｔ／ｆ）の各時刻のレベルｓｉｎ２ωｔ＝ｓｉｎ（４πｔ／ｆ）、および、正弦波ｓｉｎ（６πｔ／ｆ）の各時刻のレベルｓｉｎ３ωｔ＝ｓｉｎ（６πｔ／ｆ）を算出（５２）し、それらを、（６／７），（３／７）および（２／７）の重みを付して加算（５６）した和
β＝(6/7)sin(２πｔ／ｆ)＋(3/7)sin(4πｔ／ｆ)＋(2/7)sin(６πｔ／ｆ）
にオペレ−タが指示したゆらぎレベルＦ０を乗算（５３）した積Ｆ０・βに、オペレ−タが与えた電源回路１２への周波数指令Ｆ２を加算（５５）して、和Ｆ１＝Ｆ２＋Ｆ０・βを表わす周波数指令値ＦdcＡ１を、電源回路１１の３相信号発生器３１Ａ１に与える。またオペレ−タが与える周波数指令Ｆ２を表わす周波数指令ＦdcＡ２を、電源回路１２の３相信号発生器３１Ａ２に与える。
【００４８】
この第４実施例のコントロ−ラ１５を除く他の要素は、上述の第１実施例のものと同一であるので、ここでの説明は省略する。
【００４９】
電源回路１１は、周波数指令ＦdcＡ１で指定された周波数Ｆ１の、電流指令ＶdcＡ１で指定されたレベルＩ１の電流を、第１リニアモ−タ３Ｆの電気コイル５，６ならびに第２リニアモ−タ３Ｌの電気コイル７，８に通電する。電源回路１２は、周波数指令ＦdcＡ２で指定された周波数Ｆ２の、電流指令ＶdcＡ２で指定されたレベルＩ２の電流を、第１リニアモ−タ３Ｆの電気コイル３，４ならびに第２リニアモ−タ３Ｌの電気コイル９，１０に通電する。上述のようにＦ１＝Ｆ２＋Ｆ０・βで、Ｆ０・βがパルス波であるので、電源回路１１が電気コイル５，６ならびに７，８に与える３相交流の周波数は、Ｆ０・β（βは(7)式のもの)の、パルス波状のゆらぎを生ずる。
【００５０】
これにより、ノズル５周りの淀み域ＳＴ１およびＳＴ２に、５，６ならびに７，８が与える推力のゆらぎが加わり、このゆらぎにより淀み域の溶鋼が流動域に移動する。すなわち
β＝(6/7)sin(２πｔ／ｆ)＋(3/7)sin(4πｔ／ｆ)＋(2/7)sin(６πｔ／ｆ）
なるパルス波状のゆらぎで駆動されて流動し、淀み域での滞留が無くなる。
【００５１】
これにより、ノズル５周りの淀み域ＳＴ１およびＳＴ２に、電気コイル３，４および電気コイル９，１０が与える推力のゆらぎβが加わり、このゆらぎにより淀み域の溶鋼が流動域に移動する。すなわちパルス波状のゆらぎで駆動されて流動し、淀み域での滞留が無くなる。
【００５２】
−第５実施例−
図１０に本発明の第５実施例を示し、その電気コイルの相互間の結線と電源回路１１Ａ，１１Ｂ，１２Ａ，１２Ｂとの接続関係を図１１に示す。上述の第１〜第４実施例では、第１組の電源回路１１から第１リニアモ−タ３Ｆの第２グル−プの電気コイル５，６および第２リニアモ−タ３Ｌの第１グル−プの電気コイル７，８に給電し、第２組の電源回路１２から第１リニアモ−タ３Ｆの第１グル−プの電気コイル３，４および第２リニアモ−タ３Ｌの第２グル−プの電気コイル９，１０に給電するようにしているが、図１０，図１１に示す第５実施例では、第１リニアモ−タ３Ｆの第１グル−プの電気コイル３，４に第２電源回路１２Ａが給電し、第２グル−プの電気コイル５，６に第１電源回路１１Ａが給電し、第２リニアモ−タ３Ｌの第１グル−プの電気コイル７，８に第４電源回路１２Ｂが給電し、第２グル−プの電気コイル９，１０に第３電源回路１１Ｂが給電する。これらの電源回路１１Ａ，１１Ｂ，１２Ａ，１２Ｂのそれぞれの構成は、上述の図４に示すものと同様である。第５実施例（図１０，図１１）のコントロ−ラ１５は、図６に示す第１実施例の機能構成のものであるが、第２〜第４実施例と同様に、図７，図８又は図９に示す機能構成のものとしてもよい。この第５実施例でも、ノズル５周りの淀みＳＴ１，ＳＴ２にゆらぎが与えられ、このゆらぎにより淀み域の溶鋼が流動域に移動する。すなわちゆらぎで駆動されて流動し、淀み域での滞留が無くなる。
【００５３】
−第６実施例−
図１２に本発明の第６実施例を示し、その電気コイルの相互間の結線と電源回路１１，１２との接続関係を図１３に示す。この実施例では、鋳型内の溶鋼ＭＭのメニスカス（表面）付近に、リニアモ−タ３Ｆ，３Ｌのｚ方向中心を合せて配置して、ノズル２からの突出流が短辺に当って上昇しそして短辺側からノズル２に向けて流れるメニスカス流（図１２の実線矢印：溶鋼注入により生ずる表層流）を時計廻りの、鋳型内壁面に沿う旋回流に矯正するための推力を与えるようにしたものである。
【００５４】
この第６実施例では、第１〜第４実施例と同様に、第１組の電源回路１１から第１リニアモ−タ３Ｆの第２グル−プの電気コイル５，６および第２リニアモ−タ３Ｌの第１グル−プの電気コイル７，８に給電し、第２組の電源回路１２から第１リニアモ−タ３Ｆの第１グル−プの電気コイル３，４および第２リニアモ−タ３Ｌの第２グル−プの電気コイル９，１０に給電するようにしている
これらの電源回路１１，１２のそれぞれの構成は、上述の図４に示すものと同様である。第６実施例（図１２，図１３）のコントロ−ラ１５は、図６に示す第１実施例の機能構成のものであるが、第２〜第４実施例と同様に、図７，図８又は図９に示す機能構成のものとしてもよい。この第６実施例では、ノズル５周りの表層の淀みＳＴ１，ＳＴ２にゆらぎが与えられ、このゆらぎにより表層淀み域の溶鋼が流動域に移動する。すなわちゆらぎで駆動されて流動し、表層淀み域での滞留が無くなる。
【００５５】
−第７実施例−
図１４に本発明の第７実施例を示し、その電気コイルの相互間の結線と電源回路１１Ａ，１１Ｂ，１２Ａ，１２Ｂとの接続関係を図１５に示す。この第７実施例も、第６実施例と同様に、メニスカス流（図１４の実線矢印：溶鋼注入により生ずる表層流）を時計廻りの、鋳型内壁面に沿う旋回流に矯正するための推力を与えるようにしたものである。この第７実施例の電源回路１１Ａ，１１Ｂ，１２Ａ，１２Ｂおよびコントロ−ラ１５の構成は、第６実施例で説明したものと同様である。この第７実施例でも、ノズル５周りの表層の淀みＳＴ１，ＳＴ２にゆらぎが与えられ、このゆらぎにより表層淀み域の溶鋼が流動域に移動する。すなわちゆらぎで駆動されて流動し、表層淀み域での滞留が無くなる。
【００５６】
−第８実施例−
図１６に本発明の第８実施例を示し、その電気コイルの相互間の結線と電源回路１１，１２との接続関係を図１７に示す。この第８実施例も、第６実施例と同様に、メニスカス流（図１６の実線矢印：溶鋼注入により生ずる表層流）に鋳型内壁面に沿う旋回流に矯正するための推力を与えるようにしたものであるが、旋回流の方向は反時計廻りである。この第８実施例では、第１〜第４実施例と同様に、第１組の電源回路１１から第１リニアモ−タ３Ｆの第２グル−プの電気コイル５，６および第２リニアモ−タ３Ｌの第１グル−プの電気コイル７，８に給電し、第２組の電源回路１２から第１リニアモ−タ３Ｆの第１グル−プの電気コイル３，４および第２リニアモ−タ３Ｌの第２グル−プの電気コイル９，１０に給電するようにしている
これらの電源回路１１，１２のそれぞれの構成は、上述の図４に示すものと同様である。第８実施例（図１２，図１３）のコントロ−ラ１５も、図６に示す第１実施例の機能構成のものであるが、第２〜第４実施例と同様に、図７，図８又は図９に示す機能構成のものとしてもよい。この第８実施例では、溶鋼注入により生ずる表層流に対してリニアモ−タの推力が逆向きで、両者の相対差（合成ベクトル）が小さくなり勝ちな表層領域ＳＴ１，ＳＴ２（図１６）に淀みを生じ易いが、そこにゆらぎが与えられ、このゆらぎにより表層淀み域の溶鋼が流動域に移動する。すなわちゆらぎで駆動されて流動し、表層淀み域での滞留が無くなる。
【図面の簡単な説明】
【図１】本発明の第１実施例の構成の概要を示すブロック図であり、鋳型１の平面図に相当するものである。
【図２】図１に示す鋳型１およびリニアモ−タの、拡大した水平横断面図である。
【図３】図２に示す鋳型１およびリニアモ−タ３Ｌの３Ａ−３Ａ線縦断面図である。
【図４】図２に示すリニアモ−タ３Ｆ，３Ｌの電気コイル間結線ならびに電源回路１１，１２との結線を示すブロック図である。
【図５】図４に示す電源回路１１の構成を示す電気回路図であり、電源回路１２も電源回路１１と同一構成である。
【図６】図１，図４および図５に示すコントロ−ラ１５の機能構成を示すブロック図である。
【図７】本発明の第２実施例で用いられるコントロ−ラ１５の機能構成を示すブロック図である。
【図８】本発明の第３実施例で用いられるコントロ−ラ１５の機能構成を示すブロック図である。
【図９】本発明の第４実施例で用いられるコントロ−ラ１５の機能構成を示すブロック図である。
【図１０】本発明の第５実施例の構成の概要を示すブロック図であり、鋳型１の平面図に相当するものである。
【図１１】図１０に示すリニアモ−タの電気コイル間結線ならびに電源回路１１Ａ，１１Ｂ，１２Ａ，１２Ｂとの結線を示すブロック図である。
【図１２】本発明の第６実施例の構成の概要を示すブロック図であり、鋳型１の平面図に相当するものである。
【図１３】図１２に示すリニアモ−タの電気コイル間結線ならびに電源回路１１，１２との結線を示すブロック図である。
【図１４】本発明の第７実施例の構成の概要を示すブロック図であり、鋳型１の平面図に相当するものである。
【図１５】図１４に示すリニアモ−タの電気コイル間結線ならびに電源回路１１Ａ，１１Ｂ，１２Ａ，１２Ｂとの結線を示すブロック図である。
【図１６】本発明の第８実施例の構成の概要を示すブロック図であり、鋳型１の平面図に相当するものである。
【図１７】図１６に示すリニアモ−タの電気コイル間結線ならびに電源回路１１，１２との結線を示すブロック図である。
【符号の説明】
１：鋳型 ２：ノズル
３，４，５，６，７，８，９，１０：電気コイル
３Ｆ：第１リニアモ−タ ３Ｌ：第２リニアモ−タ
３ａ〜３ｌ，４ａ〜４ｌ：第１グル−プの電気コイル
５ａ〜５ｌ，６ａ〜６ｌ：第２グル−プの電気コイル
７ａ〜７ｌ，８ａ〜８ｌ：第１グル−プの電気コイル
９ａ〜９ｌ，１０ａ〜１０ｌ：第２グル−プの電気コイル
１１，１１Ａ，１１Ｂ，１２，１２Ａ，１２Ｂ：電源回路
１５：コントロ−ラ
１１Ｆ，１１Ｌ：長辺 １２Ｆ，１２Ｌ：非磁性ステンレス板
１３Ｆ，１３Ｌ：銅板 １４Ｒ，１４Ｌ：短辺
１５Ｒ，１５Ｌ：銅板 １６Ｒ，１６Ｌ：非磁性ステンレス板
１７Ｆ，１７Ｌ：コア
ＭＭ：溶鋼（溶融金属） ＰＷ：パウダ
ＳＢ：鋳片 ＳＴ１，ＳＴ２：停滞域（淀み域）
U11,V11,W11：第１組の電源接続端子
U21,V21,W21：第２組の電源接続端子
U22,V22,W22：第３組の電源接続端子
U12,V12,W12：第４組の電源接続端子[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a flow control device that drives a molten metal in a mold by a linear motor.
[0002]
[Prior art]
For example, in continuous casting, molten steel is poured into a mold from a tundish, and in the mold, the molten steel is drawn out while being gradually cooled from the mold wall surface. On the upper surface of the molten steel in the mold, a powdered heat insulating material or a lubricating material (commonly called powder) for drawing a slab is introduced. If the temperatures on the mold wall surfaces at the same height are not uniform, surface cracks and shell breakage (breakout) due to seizure of the slab on the inner surface of the mold are likely to occur. If powder remains as a lump in the molten steel or on the surface of the slab, it becomes a foreign matter, that is, a defect of the slab. In order to improve this, conventionally, a linear motor is used to drive molten steel in a mold in parallel with the upper surface thereof along the mold wall surface to make the temperature of the surface in contact with the mold uniform and to reduce the temperature in the molten steel. The floating of the powder is promoted (for example, Japanese Patent Application Laid-Open No. 1-228645).
[0003]
Although the flow driving of molten steel disclosed in Japanese Patent Application Laid-Open No. 1-228645 has a certain effect, the circulating flow along the mold wall surface is disturbed by the flow of molten steel flowing into the tundish via the injection nozzle. This type of flow drive uses a linear motor type electromagnet in which an electric coil is wound around each of a plurality of magnetic poles arranged along the long side of the mold, and the electric coil is provided for each of three phases. Are connected to each phase of the three-phase power supply which is shifted by 120 ° in a bundled unit, and the voltage and / or frequency of the three-phase power supply is adjusted by an inverter or a cycloconverter. The required driving force and speed are obtained. For example, there is a type in which a linear motor is arranged along a long side of a mold and an electromagnetic driving force is applied to the molten steel to generate a circulating flow circulating along the inner wall of the mold having a uniform flow velocity distribution on the surface layer of the molten steel. When the circulating flow stably flows at a constant speed to the surface layer, the floating of bubbles is promoted, the powder is not entrained in the molten steel, the inner surface of the mold near the surface layer is wiped clean, and the stagnation of the molten steel is eliminated.
[0004]
[Problems to be solved by the invention]
However, depending on the operating conditions of the continuous casting apparatus, even when the molten steel is driven by the linear motor, the molten steel flow may not circulate smoothly, and stagnation (stagnation of the molten steel) may occur. When stagnation occurs, the powder is liable to remain in the molten steel and seizure, which causes breakout, tends to occur. In addition, gas (bubbles) such as CO generated when the molten steel changes to a solid becomes difficult to float, which causes problems such as mixing of bubbles into the slab. In particular, when the long side and the short side of the mold are relatively large and the long side is short and the short side is short, stagnation is likely to occur around the nozzle for injecting molten steel into the mold or at an intermediate point between the nozzle and the short side.
[0005]
A first object of the present invention is to avoid occurrence of stagnation, and a second object is to effectively flow and drive molten steel in a place where stagnation easily occurs.
[0006]
[Means for Solving the Problems]
(1) An electromagnet core having a plurality of slots distributed in the y direction along one side (11f) of a mold side (11F, 11L, 14R, 14L) surrounding a molten metal (MM). (17f) and a linear motor (3F) having a plurality of electric coils (3, 4) inserted into respective slots;
Energizing means (12) for energizing the electric coils (3, 4) with a polyphase alternating current for generating a moving magnetic field along the y direction; and
The current-carrying means (12) reduces the current level (I2) of the polyphase alternating current that supplies the electric coils (3, 4). As time progresses Go up and down Fluctuating Energization level control means (15) for providing fluctuation [ΔI1sin2πft, ΔI1 (6/7) sin (2πt / f) + ΔI1 (3/7) sin (4πt / f) + ΔI1 (2/7) sin (6πt / f)] : Figures 6 and 7);
Is provided.
[0007]
In addition, in order to facilitate understanding, the reference numerals of the corresponding elements or corresponding items of the embodiment shown in the drawings and described later are added for reference in parentheses.
[0008]
According to this, the amount of thrust given to the molten metal by the linear motor (3F) Gauze Laugh. That is, the direction of the thrust does not change, but the magnitude changes. Therefore, the stagnation of the molten steel that occurs when a constant thrust (steady thrust) is applied is swung in the thrust direction (forward and reverse) at the fluctuation frequency, and goes out of the stagnation region.
[0009]
That is, it moves to a position driven by a constant thrust. This eliminates long-term stagnation of molten steel due to stagnation.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
(2) An electromagnet core (17f) having a plurality of slots distributed in the y direction along one side (11f) of a mold side (11F, 11L, 14R, 14L) surrounding a molten metal (MM), and (2) A linear motor (3F) including a plurality of groups of electric coils (3, 4, 5, 6) distributed in the y-direction with the plurality of inserted electric coils as one group;
A first set of energizing means (12) for energizing a polyphase alternating current for generating a moving magnetic field along the y direction to the electric coils (3, 4) of the first group;
A second phase energizing a multi-phase alternating current for generating a moving magnetic field along the y direction to the electric coils (5, 6) of the second group adjacent to the first group (3, 4) in the y direction. A pair of energizing means (11); and
At least one (12) of the first and second sets of energizing means (11, 12) is set to the current level (I2) of the polyphase alternating current that energizes the electric coils (3, 4). As time progresses Go up and down Fluctuating Energization level control means (15:15) which gives fluctuation [ΔI1sin2πft, ΔI1 (6/7) sin (2πt / f) + ΔI1 (3/7) sin (4πt / f) + ΔI1 (2/7) sin (6πt / f)] (Fig. 6, Fig. 7);
A flow control device for molten metal comprising:
[0011]
(3) An electromagnet core (17F) having a plurality of slots distributed in the y direction along one side (11F) of the mold side surrounding the molten metal (MM), and a plurality of electric coils each inserted into each slot. (3, 4) linear motor (3F);
Energizing means (12) for energizing the electric coil with a polyphase alternating current for generating a moving magnetic field along the y direction; and
The energizing means (12) adjusts the frequency (F2) of the polyphase alternating current that energizes the electric coils (3, 4). As time progresses Go up and down Fluctuating An energization level control means (15:15) which gives fluctuation [ΔF0sin2πft, ΔF0 (6/7) sin (2πt / f) + ΔF0 (3/7) sin (4πt / f) + ΔF0 (2/7) sin (6πt / f)] (Figs. 8 and 9);
A flow control device for molten metal comprising:
[0012]
According to this, the amount of thrust given to the molten metal by the linear motor (3F) Gauze Laugh. That is, the direction of the thrust does not change, but the magnitude changes. Therefore, the stagnation of the molten steel that occurs when a constant thrust (steady thrust) is applied is swung in the thrust direction (forward and reverse) at the fluctuation frequency, and goes out of the stagnation region. That is, it moves to a position driven by a constant thrust. This eliminates long-term stagnation of molten steel due to stagnation.
[0013]
(4) An electromagnet core (17F) having a plurality of slots distributed in the y direction along one side (11F) of the mold side surrounding the molten metal (MM), and a plurality of electric coils each inserted into each slot. A linear motor (3F) including a plurality of (2) groups of electric coils (3,4 / 5,6) distributed in the y-direction, where 1 is a group;
A first set of energizing means (12) for energizing a polyphase alternating current for generating a moving magnetic field along the y direction to the electric coils (3, 4) of the first group;
A second set of energizing means (energizing means) for energizing a polyphase alternating current for generating a moving magnetic field along the y direction to the electric coils (5, 6) of the second group adjacent to the first group in the y direction. 11); and
At least one (12) of the first and second sets of energizing means is set to the frequency of the polyphase alternating current that energizes the electric coil. As time progresses Go up and down Fluctuating Energization level control means for providing fluctuation [ΔF0sin2πft, ΔF0 (6/7) sin (2πt / f) + ΔF0 (3/7) sin (4πt / f) + ΔF0 (2/7) sin (6πt / f)] (15: (Figs. 8 and 9);
A flow control device for molten metal comprising:
[0014]
(5) The molten metal flow control device according to (1), (2), (3) or (4), wherein the fluctuation is a sine wave (ΔI1sin2πft, ΔF0sin2πft).
[0015]
(6) The fluctuation is a pulse wave [ΔI1 (6) obtained by adding a sine wave of a specific frequency (1 / f) and an integer multiple thereof (2 / f, 3 / f) with a weight that is inversely proportional to the frequency. / 7) sin (2πt / f) + ΔI1 (3/7) sin (4πt / f) + ΔI1 (2/7) sin (6πt / f), ΔF0 (6/7) sin (2πt / f) + ΔF0 (3 / 7) The flow controller for molten metal according to (1), (2), (3) or (4), wherein sin (4πt / f) + ΔF0 (2/7) sin (6πt / f)].
[0016]
Other objects and features of the present invention will become apparent from the following description of embodiments with reference to the drawings.
[0017]
【Example】
-1st Example-
FIG. 1 shows an outline of the first embodiment. Molten steel MM is injected into the space surrounded by the continuous casting mold 1 through the pouring nozzle 2, and the molten steel MM ejected from the injection port of the pouring nozzle 2 to the mold 1 is at the level (z direction; height) of the pouring nozzle 2. Direction), the molten steel flows (1) and (5) directed to the short side of the mold 1. Along the long side of the mold 1, linear motors 3F and 3L are provided at the level of the injection port of the pouring nozzle 2 with four sets of electromagnets 3 to 10 aligned with the center position in the z direction. An electromagnetic force is applied to the molten steel MM.
[0018]
FIG. 2 shows a cross section of the mold 1 and the linear motors 3F and 3L shown in FIG. FIG. 3 shows an enlarged cross section taken along line 3A-3A in FIG.
[0019]
The mold 1 is composed of opposing long sides 11F and 11L and opposing short sides 14R and 14L. Each side is provided on a copper plate 13F, 13L, 15R, 15L, and a non-magnetic stainless steel plate 12F, 12L, 16R, 16L is backed.
[0020]
In this embodiment, the cores 17F, 17L of the linear motors 3F, 3L are slightly longer than the effective lengths (lengths in the x direction of the molten steel MM) of the long sides 11F, 11L of the mold, and are 48 at predetermined pitches over their entire lengths. Slots have been cut. In each slot of the core 17F of the linear motor 3F, a first set of electromagnet electric coils 3a-3l, 4a-4l and a second set of electromagnet electric coils 5a-5l, 6a-6l are mounted. . Similarly, in each slot of the core 17L of the linear motor 3L, electric coils 7a to 7l and 8a to 8l of the third set of electromagnets and electric coils 9a to 9l and 10a to 10l of the fourth set of electromagnets are mounted. Have been.
[0021]
The linear motors 3F and 3L are for applying a thrust indicated by a dotted line arrow in FIG. 1 to the molten steel MM. The first set of electromagnets 3 and 4 of the linear motor F has a relatively weak thrust and the second set. Electromagnets 5 and 6 apply a relatively strong thrust to the molten steel flow. Therefore, although the number of turns of the electric coils 3a to 3l of the first set of electromagnets 3 and the electric coils 4a to 4l of the electromagnets 4 may be reduced, a direct current for braking control or thrust distribution in the x direction may be reduced. In this embodiment, all the slots and all the electric coils of the linear motor 3F are of the same specifications so that they can be adjusted within the group or can be adapted to other controls. In this embodiment, the power supply circuit 12 for driving the first set of electromagnets 3 and 4 is weakly excited so that different thrusts are generated by the first set of electromagnets 3 and 4 and the second set of electromagnets 5 and 6. A strong exciting force is supplied from the power supply circuit 11 that drives the second set of electromagnets 5 and 6. The same applies to the linear motor 3L.
[0022]
FIG. 4 shows the connection of all the electric coils shown in FIG. In this connection, each electromagnet has six poles (N = 6), and a three-phase alternating current (M = 3) is supplied to the electric coil. For example, in FIG. 4, the electric coils 3a to 3l of the first set of electromagnets 3 of the linear motor 3F are arranged in this order in the order of u, u, V, V, w, w, U, U, v, v, W, W. It is expressed as Here, "U" represents the U-phase positive-phase energization of three-phase alternating current (current energization as it is), "u" represents the U-phase reverse-phase energization (energization 180 degrees out of phase with the U-phase), and the electric coil " This means that the U phase is applied to the electric coil "u" at the winding end while the U phase is applied to the electric coil "u" at the winding end. Similarly, “V” indicates V-phase normal-phase energization of three-phase AC, “v” indicates V-phase reverse-phase energization, “W” indicates W-phase positive-phase energization of three-phase AC, and “w” Represents reverse phase energization of the W phase.
[0023]
Terminals U11, V11 and W11 shown in FIG. 4 are power connection terminals of the electric coils 3a to 31 of the first set of electromagnets 3 and the electric coils 4a to 41 of the first set of electromagnets 4 of the linear motor 3F. U21, V21 and W21 are power connection terminals of the electric coils 5a to 5l of the second set of electromagnets 5 and the electric coils 6a to 6l of the second set of electromagnets 6 of the linear motor 3F, and the terminals U22, V22 and W22. Are power supply connection terminals of the electric coils 7a to 7l of the third set of electromagnets 7 of the linear motor 3L and the electric coils 8a to 8l of the third set of electromagnets 8, and the terminals U12, V12 and W12 are linear motors. These are power connection terminals of the electric coils 8a to 8l of the 3L fourth set of electromagnets 9 and the electric coils 10a to 10l of the fourth set of electromagnets 10.
[0024]
FIG. 5 shows a power supply circuit 11 for supplying a three-phase alternating current to the second set of electromagnets 5 and 6 of the linear motor 3F and the third set of electromagnets 7 and 8 of the linear motor 3L.
[0025]
The same applies to the configuration of the power supply circuit 12 for supplying three-phase alternating current to the first set of electromagnets 3 and 4 of the linear motor 3F and the fourth set of electromagnets 9 and 10 of the linear motor 3L.
[0026]
A thyristor bridge 22A1 for DC rectification is connected to the three-phase AC power supply (three-phase power line) 21, and its output (pulsating flow) is smoothed by the inductor 25A1 and the capacitor 26A1.
[0027]
The smoothed DC voltage is applied to a power-transistor bridge 27A1 for forming a three-phase AC, and the U-phase of the three-phase AC output from the power transistor bridge 27A1 is connected to the power connection terminals U21 and U12 shown in FIG. V21 and V12 are applied to the power supply connection terminals W21 and W12.
[0028]
The second set of electromagnets 5 and 6 of the linear motor 3F and the third set of electromagnets 7 and 8 of the linear motor 3L provide a coil voltage command value VdcA1 for generating a thrust indicated by a dotted arrow in FIG. The phase angle α calculator 24A1 calculates the conduction phase angle α (thyristor trigger-phase angle) corresponding to the command value VdcA1, and provides a signal representing the calculated phase angle α to the gate driver 23A1. The gate driver 23A1 starts the phase counting of the thyristor of each phase from the zero cross point of each phase and triggers conduction at the phase angle α. As a result, the DC voltage indicated by the command value VdcA1 is applied to the transistor bridge 27A1.
[0029]
On the other hand, the three-phase signal generator 31A1 generates a constant-voltage three-phase AC signal having a frequency specified by the frequency command value FdcA1 (in this embodiment, a center frequency of 2 Hz) and supplies the same to the comparator 29A1. A triangular wave generator 30A1 supplies a constant voltage triangular wave of 3 KHz to the comparator 29A1. When the U-phase signal is at a positive level, the comparator 29A1 is at a high level H (transistor on) when the level is equal to or higher than the level of the triangular wave provided by the triangular wave generator 30A1, and at a low level L (transistor off) when the level is lower than the level of the triangular wave. Is output to the gate driver 28A1 to the U-phase positive section (to the U-phase positive voltage output transistor). When the U-phase signal is at a negative level, the triangular wave level given by the triangular wave generator 30A1 is output. A signal of a high level H at the time below and a signal of a low level L when the level exceeds the level of the triangular wave is output to the gate driver 28A1 to the negative section of the U-phase (to the transistor for outputting the U-phase negative voltage). The same applies to the V-phase signal and the W-phase signal. The gate driver 28A1 turns on and off the transistors of the transistor bridge 27A1 in accordance with the signals addressed to each phase, positive and negative sections.
[0030]
The coil voltage command value VdcA1 and the frequency command value FdcA1 are supplied from the controller 15. The controller 15 supplies the power supply circuit 12 with the coil voltage command value VdcA1 to which the fluctuation of the frequency f (0.5 Hz in one example) is added, and supplies the power supply circuit 11 with the coil voltage command value VdcA2 without the fluctuation.
[0031]
In the first embodiment, the frequency command value FdcA1 supplied to the power supply circuit 11 and the frequency command value FdcA2 supplied to the power supply circuit 12 are constant, the output frequency of the power supply circuit 11 is F1, and the output frequency of the power supply circuit 12 is F2. It is. The current I1 flowing through the electric coil by the supply voltage of the power supply circuit 11 is
I1 = I10 + ΔI1 --- (1)
The coil current I2 of the power supply circuit 12 is
I2 = I20 + ΔI2 --- (2)
The ratio γ of the fixed current value of the coil current supplied by the power supply circuit 12 and the power supply circuit 11 is
γ = I20 / I10 (3)
And γ is constant independently of time.
[0032]
The ratio β of the fluctuation current value of the coil current supplied by the power supply circuit 12 and the power supply circuit 11 is
β = (ΔI2 / ΔI1) --- (4)
It is. here,
β = sin (ωt) −−−− (5)
ω = 2πf
f = fluctuation frequency
Then, from the equations (2), (4) and (5),

And the current I2 has a fluctuation ΔI1 · sin2πft. FIG. 6 shows a functional configuration of the controller 15 of the first embodiment. Controller 15 calculates the sum of I10 and ΔI1 given by the operator (54), and supplies current command value VdcA1 representing I1 = I10 + ΔI1 to phase angle α calculator 24A1 of power supply circuit 11. Further, a clock pulse having a frequency f proportional to the level of the fluctuation frequency instruction signal Vf given by the operator is generated and counted, that is, clocked, and the level sinωt = sin2πft at each time of the sine wave sin2πft is calculated ( 52), and I20 is added (55) to the product ΔI1sinωt multiplied by 53 (53), and the current command value VdcA2 representing the sum I2 = I20 + ΔI1sinωt is calculated by the phase angle α calculator 24A2 (not shown) of the power supply circuit 12. , 24A1). Further, frequency commands FdcA1 and FdcA2 representing frequency commands F1 and F2 given by the operator are applied to three-phase signal generators 31A1 and 31A2 (not shown, but equivalent to 31A1) of power supply circuits 11 and 12. In this embodiment, F1 and F2 are set to F1 = F2 or F1 ≒ F2 within a range of 5 to 50 Hz. In this embodiment, the fluctuation frequency f is 0.5 Hz or a value around 0.5 Hz.
[0033]
The power supply circuit 11 supplies the current of the frequency F1 specified by the frequency command FdcA1 and the level I1 specified by the current command VdcA1 to the electric coils 5, 6 of the first linear motor 3F and the electric current of the second linear motor 3L. The coils 7 and 8 are energized. The power supply circuit 12 supplies the electric current of the level I2 specified by the current command VdcA2 at the frequency F2 specified by the frequency command FdcA2 and including the fluctuation ΔI1sinωt = ΔI1sin2πft to the electric coil 3 of the first linear motor 3F. 4 and the electric coils 9 and 10 of the second linear motor 3L are energized.
[0034]
As a result, fluctuations in the thrust given by the electric coils 3, 4 and the electric coils 9, 10 are added to the stagnation areas ST1 and ST2 around the nozzle 5, and fluctuations in the frequency f are added to the molten steel in the stagnation areas ST1 and ST2. As a result, the molten steel in the stagnation area moves to the flow area. That is, the fluid flows while being driven at the frequency f, and stagnation in the stagnation region is eliminated.
[0035]
-2nd Example-
In the second embodiment, β = Σβ _i sin (iωt) --- (7)
ω = 2π (1 / f) t
β _i = ∝1 / i
1 = √ (Σ┃β _i ┃ ^Two )
In this case, i = 1 to 3 (integer) in the second embodiment.
[0036]
FIG. 7 shows a functional configuration of the controller 15 of the second embodiment. Controller 15 calculates the sum of I10 and ΔI1 given by the operator (54), and supplies current command value VdcA1 representing I1 = I10 + ΔI1 to phase angle α calculator 24A1 of power supply circuit 11. Further, a clock pulse having a frequency of 1 / f, which is inversely proportional to the level of the fluctuation frequency instruction signal Vf given by the operator, is generated and counted. Level sinωt = sin (2πt / f), level sin2ωt = sin (4πt / f) at each time of sine wave sin (4πt / f), and level sin3ωt = sin at each time of sine wave sin (6πt / f) (6πt / f) is calculated (52), and they are added (56) with weights of (6/7), (3/7) and (2/7).
β = (6/7) sin (2πt / f) + (3/7) sin (4πt / f) + (2/7) sin (6πt / f)
Is multiplied by ΔI1 (53) and I20 is added to the product ΔI1 · β (55), and the current command value VdcA2 representing the sum I2 = I20 + ΔI1 · β is given to the phase angle α calculator 24A2 of the power supply circuit 12. Further, frequency commands FdcA1 and FdcA2 representing frequency commands F1 and F2 given by the operator are applied to three-phase signal generators 31A1 and 31A2 of power supply circuits 11 and 12, respectively.
[0037]
The other elements except for the controller 15 of the second embodiment are the same as those of the first embodiment described above, and the description thereof will be omitted.
[0038]
The power supply circuit 11 supplies the current of the frequency F1 specified by the frequency command FdcA1 and the level I1 specified by the current command VdcA1 to the electric coils 5, 6 of the first linear motor 3F and the electric current of the second linear motor 3L. The coils 7 and 8 are energized. The power supply circuit 12 supplies the electric current of the frequency F2 specified by the frequency command FdcA2 at the level I2 specified by the current command VdcA2 and including the fluctuation ΔI1 · β to the electric coil 3 of the first linear motor 3F. 4 and the electric coils 9 and 10 of the second linear motor 3L are energized.
[0039]
As a result, fluctuations in the thrust given by the electric coils 3, 4 and the electric coils 9, 10 are added to the stagnation areas ST1 and ST2 around the nozzle 5, and fluctuations in the frequency f are added to the molten steel in the stagnation areas ST1 and ST2. As a result, the molten steel in the stagnation area moves to the flow area. That is, the fluid flows while being driven at the frequency f, and stagnation in the stagnation region is eliminated.
[0040]
-Third embodiment-
In the third embodiment, the fluctuation β defined by the above equation (5) is applied to the frequency F1 of the three-phase alternating current generated by the power supply circuit 11.
[0041]
FIG. 8 shows a functional configuration of the controller 15 of the third embodiment. The controller 15 supplies the current command values I1 and I2 given by the operator as current command values VdcA1 and VdcA2 to the phase angle α calculators 24A1 and 24A2 of the power supply circuits 11 and 12, respectively. Further, a clock pulse having a frequency 1 / f which is inversely proportional to the level of the fluctuation frequency indication signal Vf given by the operator is generated and counted, that is, clocked to calculate a sine wave β = sinωt = sin2πft (52). Then, the frequency command F2 input by the operator to be applied to the power supply circuit 12 is added (55) to the product F0.beta. = F0.sin.omega.t multiplied (53) by the fluctuation level F0 provided by the operator (55). , The frequency command F1dcA1 representing the sum F1 = F2 + F0 · sin ωt is supplied to the three-phase signal generator 31A1 of the power supply circuit 11. The controller 15 also gives the frequency command F2 inputted by the operator as a frequency command F1dcA2 to the three-phase signal generator 31A2 (not shown, equivalent to 31A1) of the power supply circuit 12.
[0042]
The other elements except for the controller 15 of the third embodiment are the same as those of the first embodiment described above, and the description thereof will be omitted.
[0043]
The power supply circuit 11 supplies the current of the frequency F1 specified by the frequency command FdcA1 and the level I1 specified by the current command VdcA1 to the electric coils 5, 6 of the first linear motor 3F and the electric current of the second linear motor 3L. The coils 7 and 8 are energized. Since F1 = F2 + F0 · sin ωt as described above, the frequency of the three-phase alternating current applied by the power supply circuit 11 to the electric coils 5, 6 and 7, 8 causes a fluctuation of F0 · sin ωt.
[0044]
The power supply circuit 12 supplies the level I2 current specified by the current command VdcA2 at the frequency F2 specified by the frequency command FdcA2 to the electric coils 3 and 4 of the first linear motor 3F and the electric coil of the second linear motor 3L. 9 and 10 are energized.
[0045]
Accordingly, fluctuations in the thrust given by 5, 6, and 7, 8 are added to the stagnation areas ST1 and ST2 around the nozzle 5, and the fluctuations move the molten steel in the stagnation area to the flow area. That is, the fluid flows while being driven by the sinusoidal fluctuation of β = sin ωt, and stagnation in the stagnation region is eliminated.
[0046]
-Fourth embodiment-
In the fourth embodiment, the fluctuation β defined by the above equation (7) is given to the three-phase alternating current frequency F1 generated by the power supply circuit 11. Also in the fourth embodiment, i = 1 to 3 (integer).
[0047]
FIG. 9 shows a functional configuration of the controller 15 of the fourth embodiment. Controller 15 supplies current commands I1 and I2 given by the operator as current commands VdcA1 and VdcA2 to phase angle α calculators 24A1 and 24A2 of power supply circuits 11 and 12, respectively. Further, a clock pulse having a frequency of 1 / f, which is inversely proportional to the level of the fluctuation frequency instruction signal Vf given by the operator, is generated and counted. Level sinωt = sin (2πt / f), level sin2ωt = sin (4πt / f) at each time of sine wave sin (4πt / f), and level sin3ωt = sin at each time of sine wave sin (6πt / f) (6πt / f) is calculated (52), and they are added (56) with weights of (6/7), (3/7) and (2/7).
β = (6/7) sin (2πt / f) + (3/7) sin (4πt / f) + (2/7) sin (6πt / f)
Is added to the product F0.beta. (53) multiplied by the fluctuation level F0 designated by the operator (53), and the frequency command F2 to the power supply circuit 12 given by the operator is added (55), and the sum F1 = F2 + F0.beta. Is given to the three-phase signal generator 31A1 of the power supply circuit 11. A frequency command FdcA2 representing a frequency command F2 given by the operator is given to a three-phase signal generator 31A2 of the power supply circuit 12.
[0048]
The other elements except for the controller 15 of the fourth embodiment are the same as those of the first embodiment described above, and the description thereof will be omitted.
[0049]
The power supply circuit 11 supplies the current of the frequency F1 specified by the frequency command FdcA1 and the level I1 specified by the current command VdcA1 to the electric coils 5, 6 of the first linear motor 3F and the electric current of the second linear motor 3L. The coils 7 and 8 are energized. The power supply circuit 12 supplies the current of the frequency F2 specified by the frequency command FdcA2 and the level I2 specified by the current command VdcA2 to the electric coils 3 and 4 of the first linear motor 3F and the electric current of the second linear motor 3L. The coils 9 and 10 are energized. As described above, since F1 = F2 + F0 · β and F0 · β is a pulse wave, the frequency of the three-phase alternating current that the power supply circuit 11 gives to the electric coils 5, 6, and 7, 8 is F0 · β (β is ( 7), the pulse wave-like fluctuation occurs.
[0050]
Accordingly, fluctuations in the thrust given by 5, 6, and 7, 8 are added to the stagnation areas ST1 and ST2 around the nozzle 5, and the fluctuations move the molten steel in the stagnation area to the flow area. Ie
β = (6/7) sin (2πt / f) + (3/7) sin (4πt / f) + (2/7) sin (6πt / f)
The flow is driven by the fluctuation of the pulse wave, and the stagnation is eliminated.
[0051]
Thus, fluctuation β of the thrust given by electric coils 3 and 4 and electric coils 9 and 10 is applied to stagnation areas ST1 and ST2 around nozzle 5, and the fluctuation moves molten steel in the stagnation area to the flow area. In other words, the fluid flows while being driven by the pulse-like fluctuation, and the stagnation in the stagnation region is eliminated.
[0052]
-Fifth embodiment-
FIG. 10 shows a fifth embodiment of the present invention, and FIG. 11 shows the connection between the electric coils and the power supply circuits 11A, 11B, 12A, and 12B. In the above-described first to fourth embodiments, the electric coils 5 and 6 of the second group of the first linear motor 3F and the first group of the second linear motor 3L are provided from the power supply circuit 11 of the first set. Of the first group of electric coils 3 and 4 of the first linear motor 3F and the second group of second linear motors 3L. Although power is supplied to the electric coils 9 and 10, in the fifth embodiment shown in FIGS. 10 and 11, the second power supply circuit is connected to the electric coils 3 and 4 of the first group of the first linear motor 3F. 12A supplies power, the first power supply circuit 11A supplies power to the second group of electric coils 5 and 6, and the fourth power supply circuit 12B supplies to the first group of electric coils 7 and 8 of the second linear motor 3L. And the third power supply circuit 11B supplies power to the electric coils 9 and 10 of the second group. The configuration of each of these power supply circuits 11A, 11B, 12A, 12B is the same as that shown in FIG. The controller 15 of the fifth embodiment (FIGS. 10 and 11) has the functional configuration of the first embodiment shown in FIG. 6, but is similar to that of the second to fourth embodiments. 8 or the functional configuration shown in FIG. Also in the fifth embodiment, fluctuations are given to the stagnation ST1 and ST2 around the nozzle 5, and the fluctuation moves the molten steel in the stagnation region to the flow region. In other words, it is driven by fluctuation and flows, and stagnation in the stagnation region is eliminated.
[0053]
-Sixth embodiment-
FIG. 12 shows a sixth embodiment of the present invention, and FIG. 13 shows the connection between the electric coils and the connection between the power supply circuits 11 and 12. In this embodiment, the linear motors 3F and 3L are arranged near the meniscus (surface) of the molten steel MM in the mold so that the center of the linear motors 3F and 3L in the z direction is aligned, and the protruding flow from the nozzle 2 rises on the short side and A thrust for correcting a meniscus flow flowing from the short side toward the nozzle 2 (solid arrow in FIG. 12: surface flow generated by molten steel injection) into a clockwise swirling flow along the inner wall surface of the mold. It is.
[0054]
In the sixth embodiment, similarly to the first to fourth embodiments, the electric coils 5, 6 of the second group of the first linear motor 3F and the second linear motor 3 The 3L first-group electric coils 7 and 8 are supplied with power, and the second group of power supply circuits 12 supplies the first linear motor 3F with the first-group electric coils 3 and 4 and the second linear motor 3L. Is supplied to the electric coils 9 and 10 of the second group.
The configuration of each of these power supply circuits 11 and 12 is the same as that shown in FIG. The controller 15 in the sixth embodiment (FIGS. 12 and 13) has the functional configuration of the first embodiment shown in FIG. 6, but is similar to the second to fourth embodiments in FIGS. 8 or the functional configuration shown in FIG. In the sixth embodiment, fluctuations are given to the surface stagnation ST1 and ST2 around the nozzle 5, and the fluctuation moves the molten steel in the surface stagnation region to the flow region. That is, the fluid is driven by the fluctuation and flows, and stagnation in the surface stagnation region is eliminated.
[0055]
-Seventh embodiment-
FIG. 14 shows a seventh embodiment of the present invention, and FIG. 15 shows the connection between the electric coils and the connection between the power supply circuits 11A, 11B, 12A, and 12B. Also in the seventh embodiment, similarly to the sixth embodiment, the thrust for correcting the meniscus flow (solid arrow in FIG. 14: surface flow generated by molten steel injection) into a clockwise swirling flow along the inner wall surface of the mold is provided. It is something to give. The configurations of the power supply circuits 11A, 11B, 12A, 12B and the controller 15 of the seventh embodiment are the same as those described in the sixth embodiment. Also in the seventh embodiment, the surface stagnation ST1 and ST2 around the nozzle 5 are fluctuated, and the fluctuation causes the molten steel in the surface stagnation region to move to the flow region. That is, the fluid is driven by the fluctuation and flows, and stagnation in the surface stagnation region is eliminated.
[0056]
-Eighth embodiment-
FIG. 16 shows an eighth embodiment of the present invention, and FIG. 17 shows the connection between the electric coils and the connection between the power supply circuits 11 and 12. In the eighth embodiment, as in the sixth embodiment, a thrust for correcting a meniscus flow (solid arrow in FIG. 16: surface flow generated by molten steel injection) into a swirling flow along the mold inner wall surface is applied. However, the direction of the swirling flow is counterclockwise. In the eighth embodiment, similarly to the first to fourth embodiments, the electric coils 5 and 6 of the second group of the first linear motor 3F and the second linear motor are provided from the first set of power supply circuits 11. The 3L first-group electric coils 7 and 8 are supplied with power, and the second group of power supply circuits 12 supplies the first linear motor 3F with the first-group electric coils 3 and 4 and the second linear motor 3L. Is supplied to the electric coils 9 and 10 of the second group.
The configuration of each of these power supply circuits 11 and 12 is the same as that shown in FIG. The controller 15 of the eighth embodiment (FIGS. 12 and 13) also has the functional configuration of the first embodiment shown in FIG. 6, but similarly to the second to fourth embodiments, FIG. 8 or the functional configuration shown in FIG. In the eighth embodiment, the thrust of the linear motor is opposite to the surface flow caused by the injection of molten steel, and the relative difference (synthetic vector) between the two is small, and the surface regions ST1 and ST2 (FIG. 16) tend to stagnate. However, a fluctuation is given to the molten steel, and the fluctuation moves the molten steel in the surface stagnation region to the flow region. That is, the fluid is driven by the fluctuation and flows, and stagnation in the surface stagnation region is eliminated.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an outline of a configuration of a first embodiment of the present invention, and corresponds to a plan view of a mold 1. FIG.
FIG. 2 is an enlarged horizontal cross-sectional view of the mold 1 and the linear motor shown in FIG.
FIG. 3 is a vertical sectional view taken along line 3A-3A of the mold 1 and the linear motor 3L shown in FIG.
FIG. 4 is a block diagram showing connection between electric coils of the linear motors 3F and 3L shown in FIG. 2 and connection to power supply circuits 11 and 12;
5 is an electric circuit diagram showing a configuration of the power supply circuit 11 shown in FIG. 4, and a power supply circuit 12 has the same configuration as the power supply circuit 11. FIG.
FIG. 6 is a block diagram showing a functional configuration of a controller 15 shown in FIGS. 1, 4 and 5;
FIG. 7 is a block diagram showing a functional configuration of a controller 15 used in a second embodiment of the present invention.
FIG. 8 is a block diagram showing a functional configuration of a controller 15 used in a third embodiment of the present invention.
FIG. 9 is a block diagram showing a functional configuration of a controller 15 used in a fourth embodiment of the present invention.
FIG. 10 is a block diagram showing an outline of a configuration of a fifth embodiment of the present invention, and corresponds to a plan view of a mold 1. FIG.
11 is a block diagram showing connection between electric coils of the linear motor shown in FIG. 10 and connection to power supply circuits 11A, 11B, 12A and 12B.
FIG. 12 is a block diagram showing an outline of a configuration of a sixth embodiment of the present invention, and corresponds to a plan view of a mold 1.
13 is a block diagram showing connection between electric coils of the linear motor shown in FIG. 12 and connection to power supply circuits 11 and 12. FIG.
FIG. 14 is a block diagram showing an outline of a configuration of a seventh embodiment of the present invention, and corresponds to a plan view of a mold 1. FIG.
15 is a block diagram showing connection between electric coils of the linear motor shown in FIG. 14 and connection to power supply circuits 11A, 11B, 12A and 12B.
FIG. 16 is a block diagram showing an outline of a configuration of an eighth embodiment of the present invention, and corresponds to a plan view of the mold 1. FIG.
17 is a block diagram showing connection between electric coils of the linear motor shown in FIG. 16 and connection to power supply circuits 11 and 12. FIG.
[Explanation of symbols]
1: Mold 2: Nozzle
3,4,5,6,7,8,9,10: Electric coil
3F: 1st linear motor 3L: 2nd linear motor
3a-3l, 4a-4l: Electric coil of the first group
5a-5l, 6a-6l: electric coil of the second group
7a to 7l, 8a to 8l: Electric coil of the first group
9a to 9l, 10a to 10l: Electric coil of the second group
11, 11A, 11B, 12, 12A, 12B: Power supply circuit
15: Controller
11F, 11L: long side 12F, 12L: non-magnetic stainless steel plate
13F, 13L: copper plate 14R, 14L: short side
15R, 15L: Copper plate 16R, 16L: Non-magnetic stainless plate
17F, 17L: core
MM: molten steel (molten metal) PW: powder
SB: Slab ST1, ST2: Stagnation area (stagnation area)
U11, V11, W11: First set of power connection terminals
U21, V21, W21: Second set of power connection terminals
U22, V22, W22: Third set of power connection terminals
U12, V12, W12: Fourth set of power connection terminals

Claims (6)

A linear motor having an electromagnet core having a plurality of slots distributed in the y-direction along one side of a mold side surrounding the molten metal, and a plurality of electric coils inserted into each of the slots;
Energizing means for energizing the electric coil with a polyphase alternating current for generating a moving magnetic field along the y direction;
Energization level control means for giving fluctuation, which is a fluctuation that rises and falls with time, to the current level of the polyphase alternating current that energizes the electric coil;
A flow control device for molten metal comprising: An electromagnet core having a plurality of slots distributed in the y direction along one side of a mold side surrounding the molten metal, and a plurality of electric coils inserted in each slot are distributed in the y direction with a plurality of electric coils as one group. A linear motor including a plurality of groups of electric coils;
A first set of energizing means for energizing a polyphase alternating current for generating a moving magnetic field along the y direction to the electric coils of the first group;
a second set of energizing means for energizing a polyphase alternating current for generating a moving magnetic field along the y direction to an electric coil of the second group adjacent to the first group in the y direction;
Energization level control means for at least one of the first set and the second set of energization means for providing a fluctuation, which is a fluctuation that rises and falls as time progresses, with respect to the current level of the polyphase alternating current energizing the electric coil;
A flow control device for molten metal comprising: A linear motor having an electromagnet core having a plurality of slots distributed in the y-direction along one side of a mold side surrounding the molten metal, and a plurality of electric coils inserted into each of the slots;
Energizing means for energizing the electric coil with a polyphase alternating current for generating a moving magnetic field along the y direction;
Energization level control means for giving fluctuation, which is fluctuation which rises and falls with time, to the frequency of the polyphase alternating current which energizes the electric coil,
A flow control device for molten metal comprising: An electromagnet core having a plurality of slots distributed in the y direction along one side of a mold side surrounding the molten metal, and a plurality of electric coils inserted in each slot are distributed in the y direction with a plurality of electric coils as one group. A linear motor including a plurality of groups of electric coils;
A first set of energizing means for energizing a polyphase alternating current for generating a moving magnetic field along the y direction to the electric coils of the first group;
a second set of energizing means for energizing a polyphase alternating current for generating a moving magnetic field along the y direction to an electric coil of the second group adjacent to the first group in the y direction;
Energization level control means for providing at least one of the first set and the second set of energization means with fluctuations in the frequency of the polyphase alternating current energizing the electric coil , which fluctuations rise and fall with time ;
A flow control device for molten metal comprising: The molten metal flow control device according to claim 1, wherein the fluctuation is a sine wave. The melting according to claim 1, wherein the fluctuation is a pulse wave obtained by adding a sine wave having a specific frequency and a frequency that is an integral multiple thereof with a weight that is inversely proportional to the frequency and adding the sine wave. Metal flow control device.

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