| 摘要 |
PURPOSE:To reduce local variation of molten metal surface and to improve reliability by arranging plural optical molten metal surface level meters comparing positions at different positions of contacting point of inner face of a mold with the molten metal surface with the upper and lower limit values, extracting positions only in the range between the upper and lower limits and calculating the central value to make the detected molten metal surface. CONSTITUTION:Plural sets of the optical type molten metal surface level meters so as to photograph the different positions in inner face of the mold and the detected position with each optical type molten metal surface level meter is compared with the upper and lower limit values, and only the detected positions in the range between the upper and lower limits are extracted. Successively, based on the detected positions extracted, the central value is calculated, to make it the detected molten metal surface. Therefore, even if one of the optical type molten metal surface level meter comes to mal-detection or impossibility of the detection, as the other optical type molten metal surface level meter detects the molten metal surface position, this is extracted as the detected value, and then as the central value is calculated, the detecting error caused by the local variation of the molten metal is a little. |
