PURPOSE: To obtain a filter element and a fluid cleaner having large filtration areas by folding a belt-like filter medium alternately to have corrugaged longitudinal sections, curving the media in such a way that one end thereof is positioned on the inside circumferential side and the other end on the outside circumferential side and bonding both side edges.
CONSTITUTION: A sheet of belt-like filter medium having at least the two parts which are short in the transverse size at one end and is long at the other end, and are overall the optional combinations of trapezoidal, sectorial and triangular shapes is folded alternately along the folding lines extending in parallel from one side edge to the other side edge to have corrugated longitudinal sections and is then curved in such a way that one end is positioned on the inside circumferential side and the other end on the outside circumferential side, whereby a filter element is made. The discoid filter element having varying densities is obtained. The efficiency of cleaning is improved as a whole, the life is prolonged and the performance of filtration is improved considerably.
AKATSUCHI HAJIME
TAKI YOSHIHIRO
