Patent ID: 6946012
Filing Date: 2005-09-20
Classification: B01D,B31D,Y10S,Y10T

Abstract:
1. Forming apparatus for forming a filter, said filter comprising first and second sheets of filter media, said second sheet having a plurality of pleats defined by wall segments extending in zig-zag manner between pleat tips at axially extending bend lines, the pleat tips on one side of said second sheet being in contiguous relation with said first sheet and defining axial flow channels, said flow channels having a lateral cross-sectional shape comprising two adjacent included angles each greater than 45° and less than 75°, said forming apparatus comprising first and second star gears each having a plurality of teeth interdigitated with a plurality of roots therebetween, said gears rotating in intermeshed relation with the tooth of one gear in the root of the other gear, said gears passing said second sheet therebetween, said gears gathering and folding said second sheet along crease lines at said pleat tips, said crease lines providing said axially extending bend lines, wherein each said tooth has an outer end and a pair of convexly bowed sides extending from said outer end generally radially inwardly to respective roots spaced on opposite sides of the tooth.