| 摘要 |
PURPOSE:To enhance the control preciseness of a water applicating amount, by a method wherein a water distributing roller is supported by side walls for supporting a plate cylinder by shafts in an insulated state while the surfaces of both of them are used as a pair of electrodes to measure the electric resistance value of a water applicating roller held therebetween and the rotary speed of a water source roller is controlled on the basis of the measured value. CONSTITUTION:A water distributing roller 8 is supported through shafts by a side wall for supporting a plate cylinder 2 by shafts in an electrically insulated state through bearings 11 each formed of an insulating material such as engineering plastics. A brush 13 is mounted to the water distributing roller 8 while the surfaces of the plate cylinder 2 and the water distributing roller 8 are used as a pair of electrodes and AC voltage is applied between both of them and the change in the water contents of the water containing coating layers on the surfaces of water applicating rollers 9 held therebetween is detected as the change of an electric resistance value by a detection circuit 15 to control the rotary speed of a water source roller 6 on the basis of the change in the measured value by a motor control circuit 7 to control a dampening water amount. |
