| 摘要 |
PROBLEM TO BE SOLVED: To detect the level of molten metal or alloy having low melting point by irradiating light from a light source such that only a part of luminous flux is shielded by the molten surface and the remainder reaches the inner wall of a container in the advancing direction of light. SOLUTION: The surface of molten metal or alloy, which does not wet the inner wall of a container, is irradiated with light from a light source such that only a part of the luminous flux is shielded by the molten surface and the remainder reaches the inner wall of a container in the advancing direction of light. Reflected light from the molten surface and the inner wall of the container is received by a camera while forming a shadow at a part where the molten surface touches the inner wall of the container and the shadow part is detected as a molten level. More specifically, the surface of molten metal or alloy supplied from a molten holding pan 1 through a molten supply nozzle 2 into a mold 3 is projected upward in the center thereof because of the wettability thereof. When the molten surface is irradiated with light from a light source 10, a shadow part having relatively small quantity of arriving light is formed on the inner wall of the mold 3 on the side opposite to the light source 10. The shadow is picked up by a camera 11 and processed by means of a computer 12. |
