BATHTUB WATER CIRCULATING FILTER

摘要

PROBLEM TO BE SOLVED: To surely perform automatic washing of a filer medium by installing a lift pipe whose upper end is above the upper surface of an inner vessel in the center of the inner vessel filled with the filter medium and jetting out bathtub water from a nozzle to blow up the filter medium to remove wastes stuck on the surface of the filter medium. SOLUTION: A lift pipe 25 which has a prescribed distance from a jetting port 23a and is erected in an inner vessel 16 with upper end thereof being above the upper surface of the inner vessel 16 and for taking a filter medium 20 from a suction port 25a in the lower part thereof and withdraws it to a discharge port 25b in the upper part thereof is formed. Washing water is collected at a nozzle 23 and is caused to flow in and generates a jet flow to make an ejector 26 part at negative pressure. The filter medium 20 and the convection washing water are pulled in from the suction port 25a of the lift pipe 25 and is blown up in the lift pipe 25. The blown-up filter medium 20 is returned to the inner vessel 16 from the discharge port 25b, and the washing water containing SS content passes through a clearance flow passage 27b formed by a spacer 27a and the upper edge of the inner vessel 16 and flows in an annular flow passage 17 and flows out from a filter vessel.