CONTROL DEVICE OF WRAPPER ROLL IN COILER

PURPOSE:To prevent the defective coil-shape and surface flaws of a strip, by providing a position detecting means and a pressing force detecting means as well as a control-correcting means to the control loop used for controlling a driving means to add a comoponent of positional change, as a correcting signal, to a control loop. CONSTITUTION:Working oil pressures at the rod side of a cylinder 9 and its opposite side are detected by sensors 14, 15. Further, the pressing forces of wrapper rolls 5a-d are detected with the aid of an operator 16 by obtaining the output difference between the sensors 14, 15. On the other hand, when the positions of the rolls 5a-d along the radial directions of a mandrel 4 are detected with the aid of a rotationg angle detector 17 connected to the axis 8 of a swing frame 7, a changing-component detector 24 takes out only the changing component of a position signal to make it as the amount of feedback of correcting use. Accordngly a hydraulic cylinder 9 controls so that the deviations between the actual pressing forces of the rolls 5a-d and the prescribed forces are respectively settled to zero and the positional changes are negated when the positions of the rolls 5a-d tend to change.