초록 ▼

A liquid filter cartridge includes a centertube and a filtering media wrapped circumferentially about the centertube to provide a spirally wrapped media. The media includes a surface-type filtering medium having a predetermined porosity and a depth-type filtering medium which is disposed between the

A liquid filter cartridge includes a centertube and a filtering media wrapped circumferentially about the centertube to provide a spirally wrapped media. The media includes a surface-type filtering medium having a predetermined porosity and a depth-type filtering medium which is disposed between the wraps of the surface-type filtering medium. The surface-type filtering medium is a filtering paper, and the depth-type filtering medium is an air laid batt which includes structural fibers tending to support the surface-type medium and to prevent the latter from collapsing under dynamic flow conditions. The depth-type medium is porous and offers little resistance to fluid flow, so that the liquid to be filtered can easily flow both radially from one of the layers of the surface-type medium to the adjacent layer, and also can flow circumferentially to thereby permit access for the liquid to be filtered over the entire area of the inner wraps of the surface-type medium.

대표청구항 ▼

Liquid filter cartridge comprising a perforated centertube, and a filtering media wound circumferentially around said centertube, said filtering media comprising a depth type filtering medium between layers of a surface type filtering medium having a predetermined porosity placed on opposite sides o

Liquid filter cartridge comprising a perforated centertube, and a filtering media wound circumferentially around said centertube, said filtering media comprising a depth type filtering medium between layers of a surface type filtering medium having a predetermined porosity placed on opposite sides of said depth type filtering medium, said depth type filtering medium being relatively uncompressed to have a strength sufficient to maintain separation between the layers of said surface type filtering medium on opposite sides of said depth type filtering medium, and having a porosity sufficiently great to permit relatively uninhibited flow of the liquid within the depth type filtering medium both radially and circumferentially with respect to said centertube, said surface type filtering medium having sections of greater porosity relative to said predetermined porosity, said sections of greater porosity being spaced circumferentially from one another whereby said sections of greater porosity are offset radially from one another on adjacent layers of said surface type filtering medium.