Abstract: A filter device (10) for an internal combustion engine includes a separator that is embodied as a cyclone preseparator (26), a main filter element (36) exchangeably arranged in a housing compartment (68) of the filter housing (12), and a secondary filter element (38. The housing compartment (68) includes insertion stays (64). The main filter element (36) is embodied in as a double bellows filter including a first radially inwardly positioned filter bellows (40) and a second radially outwardly positioned filter bellows (42) surrounding it. Upon closing of a servicing housing cover (18) a sealing force is generated that acts onto the main filter element (36) and is maintained in the closed state of the servicing cover (18).

Abstract: A filter device (10) for an internal combustion engine includes a separator that is embodied as a cyclone preseparator (26), a main filter element (36) exchangeably arranged in a housing compartment (68) of the filter housing (12), and a secondary filter element (38. The housing compartment (68) includes insertion stays (64). The main filter element (36) is embodied in as a double bellows filter including a first radially inwardly positioned filter bellows (40) and a second radially outwardly positioned filter bellows (42) surrounding it. Upon closing of a servicing housing cover (18) a sealing force is generated that acts onto the main filter element (36) and is maintained in the closed state of the servicing cover (18).

Abstract: In a filter element (10) having a filter bellows (11) which is covered at each end by an end disk (13, 14), the end disks (13, 14) are each provided with at least one coupling element for coupling to a filter housing (20) and connected to one another via at least one central tube (12) spanning the filter bellows (11). Alternatively, a central tube which runs right through and onto which end disks and filter bellows are pushed and which is configured at its ends for coupling with parts of the housing is present.

Abstract: In order to provide a seal function and a protection of the sealing surfaces for an air filter element (10) comprising a cylindrical tubular filter bellows (11) that is closed off at the end faces by a terminal disk (20, 20?), respectively, which each have at least one annular seal (22) or an annular seal section of a sealing member, the annular seal (22) is covered by a manually removable cover ring and/or a cover disk (30?).

Abstract: A filter closure system has a connecting head with a connecting web and further has a connecting end at an end face of a filter housing. The connecting head and the connecting end are matched to one another. The connecting end is pushed onto the connecting head in a mounting direction into a mounted state on the connecting head so as provide a seal-tight connection in the mounted state. The connecting end and the connecting web that extends in the mounting direction are provided with a micro toothing. When pushing the connecting end onto the connecting head in the mounting direction, the micro toothing connects by positive locking action the connecting end and connecting head with one another. The engagement of the micro toothing between connecting end and connecting head is realized along a flank of connecting web and connecting end which flank extends in the mounting direction.

Abstract: In a filter element (10) having a filter bellows (11) which is covered at each end by an end disk (13, 14), the end disks (13, 14) are each provided with at least one coupling element for coupling to a filter housing (20) and connected to one another via at least one central tube (12) spanning the filter bellows (11). Alternatively, a central tube which runs right through and onto which end disks and filter bellows are pushed and which is configured at its ends for coupling with parts of the housing is present.

Abstract: The invention relates to a filter device (10), in particular for filtering intake air of an internal combustion engine. The filter device (10) comprises a separator that is embodied in particular as a cyclone preseparator (26), moreover a main filter element (36) exchangeably arranged in a housing compartment (68) of the filter housing (12), as well as a secondary filter element (38) that in the flow direction of the fluid to be cleaned is arranged downstream. The housing compartment (68), for facilitating premounting of the main filter element (36) therein, comprises insertion stays (64). The main filter element (36) is embodied in particular as a double bellows filter, comprising a first radially inwardly positioned filter bellows (40) and a second radially outwardly positioned filter bellows (42) surrounding it.

Abstract: To be able to insert a cylindrical filter element (10) which is joined at each end to an end disk (14) quickly into a housing element (40) in a filter unit (100) and connect it firmly, a screw connection having conical threads (16, 46) on the filter element (10) and on the bottom of the housing (41) is provided.

Abstract: The invention concerns a filter housing (1), in particular of an air filter for motor vehicles, that extends axially along a longitudinal axis (2) and comprises two detachably connected housing parts (3, 4). A locking connection (5) acting in the direction of the longitudinal axis (2) is provided between the two housing parts (3, 4), wherein the locking connection (5) in at least one rotational direction (6) of the first housing part (3) about the longitudinal axis (2) relative to the second housing part (4) can be brought into a position in which the housing parts (3, 4) are detachable in the axial direction.

Abstract: A filter system for a fluid having a cup-shaped housing releasably connected to a connecting head and a filter element arranged in the housing, in which the releasable connection is formed by at least one connecting element formed on the connecting head which engages a connecting element formed by a part of the filter element in combination with a part of the cup-shaped housing such that the connection between the housing and the receiving head can only be produced if a proper filter element is installed in the housing.

Abstract: A compact filter element in which the end faces of a plurality of nonwoven filter layers (3) are fixedly integrated into a cover (4) and in which the oncoming flow of fluid to be filtered is deflected in the cover (4) in such a way that the fluid flows respectively into every second or alternating area between two adjacent nonwoven filter layers (3) and flows through the nonwoven filter layers (3) into the intervening spaces between the spaces between filter layers in to which it initially flows, from which intervening spaces it exits the filter element.

Abstract: An air filter connecting unit having a connecting flange (11) and a connecting nipple (20) that can be coupled to the connecting flange via a snap connection. The connecting flange (11) has a round receptacle (13) provided with an inside thread flight (12) that is subdivided into individual, resilient, curved thread flight segments (12.1, 12.2, . . . , 12.n). The associated connecting nipple (20) has a generally cylindrical construction and an advancing thread (22) which ends in a free-running groove (23) on the connecting nipple.

Abstract: The invention relates to a filter device (10), in particular for filtering intake air of an internal combustion engine. The filter device (10) comprises a separator that is embodied in particular as a cyclone preseparator (26), moreover a main filter element (36) exchangeably arranged in a housing compartment (68) of the filter housing (12), as well as a secondary filter element (38) that in the flow direction of the fluid to be cleaned is arranged downstream. The housing compartment (68), for facilitating premounting of the main filter element (36) therein, comprises insertion stays (64). The main filter element (36) is embodied in particular as a double bellows filter, comprising a first radially inwardly positioned filter bellows (40) and a second radially outwardly positioned filter bellows (42) surrounding it.

Abstract: To be able to insert a cylindrical filter element (10) which is joined at each end to an end disk (14) quickly into a housing element (40) in a filter unit (100) and connect it firmly, a screw connection having conical threads (16, 46) on the filter element (10) and on the bottom of the housing (41) is provided.

Abstract: A liquid filter, especially oil filter for an internal combustion engine, having a cup-shaped housing with a liquid inlet and a liquid outlet, a filter element arranged with a seal between the inlet and outlet, and a one-piece barrier membrane arranged in the area of the opening of the cup-shaped housing such that the liquid inlet and/or the liquid outlet can be closed by the barrier membrane.

Abstract: In order to be able to adjust in a simple and inexpensive way in the manufacture of an air filter housing (10) for a cylindrical filter element, the housing comprising a tangentially adjoining unfiltered air socket (1) and an outlet socket (2) and comprising a footstep bearing element (3) formed integrally on the air filter housing, the angular position of the unfiltered air socket (1) relative to a support and fastening plane predetermined by the footstep bearing elements (3), it is provided that the air filter housing is divided into a central housing element (4), on which the footstep bearing element (3) is integrally formed, and an intake element (5), on which the unfiltered air socket (1) is integrally formed, wherein the central housing element (4) and the intake element (5) are connected to one another by a rotationally positionable connection.

Abstract: In a filter element (10) having a filter bellows (11) which is covered at each end by an end disk (13, 14), the end disks (13, 14) are each provided with at least one coupling element for coupling to a filter housing (20) and connected to one another via at least one central tube (12) spanning the filter bellows (11). Alternatively, a central tube which runs right through and onto which end disks and filter bellows are pushed and which is configured at its ends for coupling with parts of the housing is present.

Abstract: A compact filter element with a large filter surface area having inner and outer rings of filter material with an annular space between them, such that fluid to be filtered can be introduced into the annular space between the rings of filter material and a portion thereof can flow through the outer ring of filter material to the periphery of the filter element and another portion thereof can flow through the inner ring of filter material to the center of the filter element; at least one fluid-permeable support member for the filter material, and at least one end disk on an axial end face of the filter element affixed to the rings of filter material in a sealed manner, in which the end disk has a centrally arranged inlet opening for the fluid to be filtered and one or more radially extending distributor channels leading from the central inlet opening to at least one eccentrically arranged outlet opening which opens into the annular space between the rings of filter material to admit fluid to be filtered to the

Abstract: A filter apparatus including a housing (2) and a filter insert (4), with an inlet opening formed on the housing (2) and an outlet fitting (6) mounted on a housing wall. The outlet fitting (6) has a contact face (7) for contact with the housing (2) and is provided with a tubular segment (13), which protrudes through an opening (9) of the housing, and a mounting element (22) is attached to the tubular segment (13) such that a region (10) of the housing (2) surrounding the opening (9) is clamped between the contact face (7) of the outlet fitting (6) and the mounting element (22).