| 摘要 |
<p>PURPOSE:To improve the quality of a product by switching a control system of a designated side to a control system of a non-designated side, when the control system of a designated manipulated variable has reached a limited value, and also varying a limited value of a variable limiter of the designated side. CONSTITUTION:When reversible limiters 10', 30' reach control limited values G1, G2, control signals S1, S2 are outputted, and also timers 14, 34 are started, and measure the time of integral time constants TT, TV of a tension and a speed, respectively. Subsequently, the control limited values G1, G2 are reduced linearly for a prescribed time, and thereafter, returned linearly to its original level. In this case, an output of the reversible limiter 10' is in a saturated state, therefore, when the limit G1 is reduced, the output of the limiter 10' also follows it and becomes small. According to this method, a speed AGC system operates without interfering with a tension AGC system, and works so that a deviation of a plate thickness of the delivery becomes zero. Accordingly, the plate thickness accuracy is stabilized, and the quality of a product is improved.</p> |
