FILTER DEVICE AND FILTERING METHOD

摘要

PROBLEM TO BE SOLVED: To enhance the release property of solid mater stuck to a filter element at the time of back washing and to shorten the back washing time. SOLUTION: The inlet 12 and the outlet 13 divided with a tube plate 14 are provided at a cylindrical main body 11, and one end part of the plural long and thin coil type filter elements 15 having a spring property are mounted onto the tube plate 14. The piston 16 whose outer periphery is brought into sliding contact with the inner surface of the main body is arranged in the main body 11, and the other end parts of the filter elements 15 are mounted to the piston 16. The piston 16 is driven by the driving means 29 by the fluid pressure in the main body 11 so that each filter element 15 is compressed.