| 摘要 |
PURPOSE:To detector positively a material level in a smelting furnace, by inserting an electrode sensor in a specified level position and connecting this electrode sensor and that located in lower position to a detecting electric circuit. CONSTITUTION:In a tower part 5 of a smelting furnace for aluminum material and in the lowest level position to be held for preheating aluminum material M, a sensor 9 is set free to be introduced and withdrawn in a direction shown with an arrow. When aluminum material M is charged above the lowest level position and when the electrode sensor 9 is introduced inside the furnace, the dielectric aluminum material M itself constitutes a part of a detecting electric circuit 16 and consequently, an alarm lamp 15 is not turned on. On the other hand, when the aluminum material M comes down lower than the electrode sensor 9 specified lowest level, then insertion of the electrode sensor 9 in the furnace does not establish a dielectric path and then, the lamp is turned on to give alarm that the material M is short. |
