HEATING AND MOLDING METHOD FOR FILTER ELEMENT

PURPOSE:To mold a filter element into a round concentric shape by pressing a heated mold on the crest part and the root part of the filter element which is bent to a corrugate type and made to a ring-shape, and thereafter cooling it. CONSTITUTION:A filter element 10 is rounded in a ring-shape by cutting a lamellar filter medium to a sector and bending it to corrugate type shapes in the cross-section with prescribed intervals in the circular arc direction of the sector. The filter element 10 is fitted to a lower mold having concentric circular fins 18 and root parts 20. Then an upper mold having concentric circular arc-like fins 60 pressurizing the root parts 14 of the filter element 10 is pressed. The fins 60 and grooves 62 of the upper mold are heated with a heater 36 and both the crest parts 12 and root parts 14 of the filter element 10 are heated and molded. Thereby the filter element 10 which were not the concentric circular shape but were an angularly bent shape can be worked to the concentric circular shape at extremely short time because the crest parts 12 and the root parts 14 are heated and molded.