| 摘要 |
<p>Sensing element (60, 62, 65) senses the level (61) of molten metal in the DC or EM casting apparatus and generates a signal proportional to the level sensed; the level signal is compared with a set point signal representing the desired molten metal level, an error signal is generated for differences between the signal representing the level sensed and the set point signal, and the flow of molten metal to the DC or EM casting apparatus is controlled by a control assembly which operates in response to and in a manner proportional to the error signal. A master controller (80) holds the set point signal and supplies it to individual local controllers (71) each of which by way of associated actuator (56) regulates molten metal flow to the associated casting zone. Melt flow is regulated by a pin or plug (40) which is raised or lowered directly or indirectly by the rotation of a cam shaped like an Archimedes spiral to ensure proportional regulation. <IMAGE></p> |
