DEVICE FOR CLEANING DAMPENING WATER IN AN OFFSET PRESS

摘要

A filter device suitable for use in cleaning dampening water used in an offset press. The filter device has a tank in which are defined three sections: a stirring tank section, a floating tank section and a discharging tank section. The floating tank section and the discharging tank section are communicated with each other through a passage at their lower regions. The passage is adapted to be selectively closed by a shut-off device which is operated periodically under the control of a timer. A floating contaminant removing opening es positioned above the water level in the floating tank section. The contaminated water is poured into the stirring tank section through a bubbling means so that contaminants are adsorbed by the bubbles. The bubbles adsorbing the contaminants are allowed to float in the upper region of water in the floating tank section. When the passage is shut off by the shut-off device, the water level in the floating tank section is raised so that the contaminants are removed together with the bubbles through the floating matter removing opening. On the other hand, the cleaned water free of contaminants flows into the discharging tank section through the passage and discharged outside the tank so as to be recirculated to the offset through a filter.