Patent ID: 8043504

Claim:
A filter cartridge, comprising: an outer filter that includes first filter media, and an endplate attached to an end of the first filter media, the outer filter including a central axis; the endplate includes: an outer portion that includes a segment attached to the first filter media, and a first ring-shaped portion with a first radially-inward facing rim, the segment attached to the first filter media is substantially flat and horizontal; an inner portion substantially surrounded by the outer portion, the inner portion includes a second ring-shaped portion disposed within the first ring-shaped portion, the second ring-shaped portion including a radially-outward facing rim that generally faces the first radially-inward facing rim, and a second radially-inward facing rim that defines a central opening; a connecting portion that flexibly connects the outer portion and the inner portion so that the inner portion and the outer portion are moveable relative to one another to permit relative movements therebetween, the connecting portion includes a plurality of resilient arms connected between the first radially-inward facing rim and the radially-outward facing rim, the arms permitting relative movements between the second ring-shaped portion and the first ring-shaped portion; and at least one opening in the endplate between the outer portion and the inner portion; an inner filter that includes second filter media, an end of the second filter media is connected to the inner portion, and the inner filter is sized to at least partially fit within the outer filter, and the inner filter includes a central axis coaxial to the central axis of the outer filter.