| 摘要 |
PURPOSE:To provide a check sensor for molten metal level position which is prevented from a delay in a response time even if a thermocouple deteriorates, by a method wherein a thermocouple is mounted at a molten metal feed pipe, and a change in an electromotive force, produced at a time when the thermocouple makes contact with molten metal, is detected. CONSTITUTION:A tilting part 6A of a molten metal feed pipe 6 is inserted into a crucible furnace 1 which is provided with a lid 2 at the upper part and with a heater 3 at the outer circumference, and stows a molten metal 4. A stop punch, blockading a molten metal feed port 6C, and a thermocouple 8, detecting a molten metal level, are positioned at a falling part 63 of the molten metal feed pipe 6. Compressed air is fed into the furnace 1 through a compressed air pipe 5 in the lid 2, and the molten metal 4 is raised up to the position of the thermocouple 8 through the tilting part 6A and molten metal feed port 6A to make contact with the thermocouple 8. Resulting from the contact of the thermocouple with the molteh metal, the electromotive force changes sharply. A detecting part, consistig of an amplifier 9, connected to the output of the thermocouple 8, a check part 10 for a change in an electromotive force, and a signal check part 11, detects said change, and this permits the measurement of the position of the molten metal. |
