Patent ID: 6840386

Claim:
A unitary centertube for use as part of a fluid filter, said unitary centertube comprising; a tubular body portion defining an interior opening and including a plurality of annular ribs and a plurality of recessed sections, each recessed section formed between respective ones of said annular ribs and axially spaced along an outer surface of said body portion; a cross-beam section positioned in said interior opening and being constructed and arranged in unitary combination with said tubular body portion, said cross-beam section constructed and arranged for partitioning said interior opening into four quadrant volumes, said tubular body portion including a longitudinal dimension and said cross-beam section extending axially through said interior opening for a majority of said longitudinal dimension; and wherein each recessed section of said plurality of recessed sections defines at least one first fluid flow aperture having a first configuration and opening into a first one of said four quadrant volumes and at least one second fluid flow aperture having a second configuration that is different from said first configuration and opening into a second one of said four quadrant volumes.