METHOD AND APPARATUS FOR FORMING FILTER ELEMENT

摘要

A tape like material including synthetic resin for a filter element is bent into a corrugated pattern while the material is passed between pairs of forming and cutting rollers. Since pairs of cutters are provided within the rollers and since guide plates are provided around the rollers, the material is held abutting the rollers even when the material is cut by the cutters. The material is then conveyed within a reducing drum. The pitch of the corrugated portions formed on the material is reduced and the material is formed into a semicircular shape within the reducing drum. After passed the reducing drum, the material is transferred to a forming path. Since the forming path has an introducing portion having a semicircular sectional shape similar to that of the material leaving the reducing drum, an outlet portion having a circular sectional shape similar to that of the finished filter element and an intermediate portion having a sectional shape gradually varied from the shape of the introducing portion to the shape of the outlet portion, the material is shaped to a complete circle while the material travels along the forming path. A crystal type filter element is thus formed from a tape like material automatically.