A fluid treatment device has an exchangeable treatment unit and a connection head. A bayonet-type connection device connects connection head and treatment unit to each other by a plug-in/rotation movement about a connection axis of the treatment device and is provided with a housing connection part and a head connection part that operatively engage each other to form a connection of the bayonet-type connection device. Housing connection part and head connection part each have a mutually complementary functional element extending circumferentially about the connection axis and operatively connectable to each other. The bayonet-type connection device has a pretension element for realizing a mechanical pretension pressing the functional elements against each other. The pretension element is a spring element with outwardly projecting spring arms with radially outer end faces provided with a straight section that is tangential to a rim extending in circular shape around the connection axis.

A filter element includes a bottom open end joined to a center tube opposite the top open end. The bottom open end defines a radially outer surface and a radially inner surface that is in communication with the central reservoir of the filter element. A locking feature is disposed proximate to the bottom open end. The locking feature includes an entrance slot that is disposed on the radially inner surface of the center tube extending axially from the bottom open end.

A filter element includes a bottom open end joined to a center tube opposite the top open end. The bottom open end defines a radially outer surface and a radially inner surface that is in communication with the central reservoir of the filter element. A first locking feature is disposed proximate to the bottom open end. The locking feature includes an entrance slot that is disposed on the radially inner surface of the center tube extending axially from the bottom open end. A similar or identical second locking feature is disposed proximate to the top open end.

A filter head assembly includes a filter head and a threaded bayonet connection adapter having a rotational position tolerance improving retainer ring. The rotational position tolerance improving retainer ring providing for and enabling the critical further deformation of the rotational position tolerance improving retainer ring beyond the predetermined final assembly torque to achieve the required critical final rotational position of the threaded bayonet connection adapter for the correct operation of the open and locked position indicators on the filter head.

A filter system for liquid has a filter head with drainage channel and stop element. A filter cartridge is mounted by screw-in movement at the filter head and has a support ring rotatably fastened to its housing part. The support ring has an eccentric closure element and a first positioning element guided toward the stop element by the screw-in movement to position the support ring at the filter head in a rotational position for axially aligning closure element and drainage channel. The closure element is transferred axially into a sealing seat at the filter head to close the drainage channel when screwing on the filter cartridge. The support ring has a second positioning element holding the support ring in a rotationally fixed position at the filter head when unscrewing the filter cartridge so that the closure element is moved out of the sealing seat only in an axial direction.

A filter system for liquid media has a filter housing with housing pot and housing cover. The housing pot has a drainage channel with bottom-side drainage opening. A bottom end disk of a filter element has a closure element arranged off-center to a longitudinal filter element axis. The closure element, in predetermined installation position of the filter element, extends seal-tightly across or into the drainage opening. The bottom end disk has a cutout corresponding with a positioning aid of the housing pot. By screwing on the housing cover, the filter element moves with the housing cover axially toward the drainage opening and rotates until positioning aid and cutout engage and lock the filter element relative to the housing pot in a predetermined rotational position where the closure element is axially aligned with the drainage opening. The filter element moves with the housing cover axially into the predetermined installation position.

The present invention relates to a filter element comprising an oil filter port adapted to be in fluid communication with an oil port of an engine the oil filter port includes threads for attaching the filter element in the oil port of the engine. Thus, the inventors realized that by providing the oil port with threads, the oil port of the filter element may be tightened in the oil port of the engine to in this way ensure axial locking of the filter element in the engine. The present invention also relation to a corresponding filter housing.

A filter device comprises a filter housing having a filter housing cup and a filter housing cover. An insert insertable into the filter housing comprises an eccentrically arranged and axially projecting first positioning element configured to engage a positioning contour on a side of the filter housing cup. A guide ramp is provided on the filter housing cup and interacts with a guide device arranged on the insert. The guide ramp is formed of at least one ring segment and extends continuously over at most 270°, and the guide device has a second positioning element. At least one web is arranged on the insert and forms the second positioning element, and the at least one web comprises at least two webs with different axial longitudinal extents arranged one of on the lower end plate of the insert and directly on the insert.

A connector assembly for fluid filter elements is provided comprising first and second connector elements each comprising at least two connector snap arches, each of the connector snap arches including a snap tooth lock; and at least two connector snap arms, each of the connector snap arms including a snap tooth; each connector element having a central opening, and an annular channel for receiving an end of a hollow cylindrical filter element; a gasket arranged between the first connector element and the second connector element, the gasket having a central opening; wherein the first connector element and the second connector element are lockably engageable with each other when placed in contact with each other and axial force is applied such that respective connector snap tooth is retained in each respective connector snap tooth.

A filter cartridge is for a vehicle fluid filter group that includes a filter body and cartridge engagement members in the filter cartridge and body engagement members in the filter body. The cartridge engagement members and body engagement members are configurable by mutual axial movement between an engagement configuration and a disengagement configuration. The cartridge filter includes an end plate with the cartridge engagement members arranged around the cartridge axis. The cartridge engagement members include two blocking groups, each blocking group including a blocking element. Each blocking element includes a stem and a tooth laterally projecting from the stem and defining an engagement undercut. In the blocking configuration, the tooth is in a housing region of the body engagement members, and an engagement projection is housed in the undercut. In axial movements, each stem yields elastically radially and/or laterally upon action of the engagement projection on the tooth.