| 摘要 |
PURPOSE:To prevent overloading of an electric motor for oscillating a casting mold and to stabilize operation by limiting the threshold oscillation frequency with respect to a stroke length from the permissible torque of the motor and controlling the actual oscillation frequency in the stage of operation. CONSTITUTION:The threshold oscillation frequency for each stroke length is preliminarily calculated from the permissible torque of an electric motor 18 for oscillation and is inputted to an auxiliary control device 12. On the other hand, the oscillation frequency C with respect to the stroke length is calculated by the equation I from the casting speed V in the actual operation. In the equation, C=oscillation frequency cpm, K=constant, N=the distance lM of the vertical movement of the casting mold/the extent ls of movement of a billet, S=stroke length mm., V=casting speed mpm. The calculated frequency C is then compared with the threshold oscillation frequency and when the frequency C exceeds the threshold oscillation frequency, a correction signal is outputted from a main control panel 4 so as to decrease the casting speed V and at the same time an alarm signal is outputted therefrom. |
