A filter device has a filter housing and a round filter element received in the interior of the filter housing. The round filter element has a filter medium body with a wall flowed through radially relative to a longitudinal axis of the filter medium body by a fluid to be purified. The round filter element has a first end disk and a second end disk arranged at opposed end faces of the filter medium body. The filter medium body has an inwardly positioned flow space inside the filter medium body that is the raw side of the round filter element. A support grid is arranged externally at the wall of the filter medium body. The filter housing has a housing cover with a flow guiding rib arranged at an inner side of the housing cover facing the interior. The flow guiding rib projects into the inwardly positioned flow space.

Filter cartridges including tubular filter media having ovate cross-sections and filter systems using the ovate tubular filter cartridges are described herein. The inner perimeters of the ovate cross-sections of one or more of the filter cartridges may be asymmetric, i.e., the inner perimeters of the cross-sections of the tubular filter media in the filter cartridges may have no lines about which they are symmetric. The inner perimeters of the ovate cross-sections of the tubular filter media in one or more of the filter cartridges may have only one line of symmetry.

A filter element is provided having a tubular shape defining an inner space, a first outlet in communication with the inner space and a second outlet in communication with the inner space, wherein the second outlet has an offset position in relation to the first outlet in a transversal direction of the filter element. Also provided is a filter housing having an inner housing space adapted to receive a tubular filter element, the filter housing having an inlet, a first outlet located in a first end of the filter housing, and a second outlet located in a second end of the filter housing, wherein the second end is located opposite to the first end in relation to the inner housing space.

A round filter element has a filter medium body with a wall to be flowed through by a fluid to be purified in a radial direction relative to a longitudinal axis of the filter medium body. A circumferentially extending seal carrier is arranged at or adjacent to an end face of the filter medium body. A sealing element is supported at the seal carrier adjacent to a radial outer side of the filter medium body. A positioning element extends into the filter medium body and engages with a correlated housing-associated counter positioning element of a filter housing when the round filter element is installed in the filter housing. The seal carrier separates flow-tightly a raw side of the round filter element from a clean side of the round filter element when the round filter element is installed in the filter housing.

A filter cartridge, a safety element and fluid cleaner assembly are described. The fluid cleaner assembly generally includes a housing having a cover and a primary fluid cleaner section. The filter cartridge generally comprises z-filter media, arranged in a straight through configuration. Preferred cartridges include a seal gasket positioned to extend continuously around at outer perimeter of the straight through flow construction. The fluid cleaner assembly can have a precleaner positioned therein. Preferred features are described. Methods of assembly and use are also provided.

Filter cartridges including tubular filter media having ovate cross-sections and filter systems using the ovate tubular filter cartridges are described herein. The inner perimeters of the ovate cross-sections of one or more of the filter cartridges may be asymmetric, i.e., the inner perimeters of the cross-sections of the tubular filter media in the filter cartridges may have no lines about which they are symmetric. The inner perimeters of the ovate cross-sections of the tubular filter media in one or more of the filter cartridges may have only one line of symmetry.

An air filter element for an air filter for an internal combustion engine is provided with a filter medium surrounding annularly a longitudinal axis of the air filter element. A first end disk is provided at a first end face of the air filter element, wherein the filter medium is embedded in the first end disk at the first end face. A clean air seal is configured to seal a raw side of the air filter against a clean side of the air filter. The clean air seal and the first end disk are embodied together as one piece. The clean air seal protrudes continuously radially past the filter medium. A filter housing for the air filter element is provided with a filter pot and a cover and has a clean air outlet and a raw air inlet arranged at a side wall of the filter pot.

An air filter element has a filter medium body that has a wall to be flowed through by a fluid to be purified in a radial direction relative to a longitudinal axis of the filter medium body. The filter medium body has a first end face and an oppositely positioned second end face. The filter medium body has an elongate cross section shape with two oppositely positioned narrow sides and two oppositely positioned long sides connecting the two narrow sides. A cross section surface of the filter medium body tapers from the first end face toward the second end face. The two long sides each have an inwardly oriented radial constriction in a region of the narrow second end face, wherein, in a region of the first end face, the two long sides are formed without or at least approximately without the inwardly oriented radial constriction, respectively.

A cover for a filter system for filtering a fluid has a fluid channel arranged at an inner side of the cover. The cover has a rim and at least one opening arranged in the rim to allow the fluid to pass through, wherein the opening is connected in fluid communication with the fluid channel. The fluid channel is connected in fluid communication with the interior of a filter element of the filter system. A seal for the cover has a first sealing ring and a second sealing connected to each other by flanks. The filter system has a housing with a housing part that is closable by the cover. A filter element is exchangeably arranged in the housing, and the fluid channel of the cover is connected in fluid communication to the interior of the filter element.

A secondary filter element for a filter arrangement is provided with a filter medium and a circumferentially extending sealing device that seals the secondary filter element in respect to a filter receptacle of the filter arrangement. The circumferentially extending sealing device has an oval geometry with a long side and a short side. The circumferentially extending sealing device has an outer surface projecting, in a radial direction of the secondary filter element, farther past the filter medium when viewed along the short side compared to when viewed along the long side. A filter arrangement has a filter receptacle. A main filter element is received in the filter receptacle, and a secondary filter element is received in the main filter element. The circumferentially extending sealing device of the secondary filter element projects in a radial direction of the secondary filter element outwardly past an interior of the main filter element.