Patent ID: 8444736

Claim:
An exchangeable filter element comprising: a filter bellows of filter media, said filter bellows having two axially opposing ends; a first terminal disk connected to said filter bellows at one of said axial ends, said first terminal disk attached to a first coupling projection extending axially outwardly away from said first terminal disk; a second terminal disk connected to said filter bellows at another of said axial ends, said second terminal disk attached to a second coupling projection extending axially outwardly away from said second terminal disk; a stabilizing element spanning said filter bellows, extending axially in a central recess of said filter bellows from said first terminal disk to said second terminal disk, said stabilizing element coupling and transmitting tensile forces between said first coupling projection and said second coupling projection; wherein said first coupling projection includes a radially open endless groove formed into a radially outer surface of said first coupling projection and extending circumferentially around said first coupling projection; wherein said endless groove is continuous and does not form a thread; wherein said endless groove is operable for engagement by at least one radially moving locking element, wherein said locking element is moved radially inwardly to engage into said endless groove: wherein said stabilizing element includes said first coupling projection and said second coupling projection; wherein said first coupling projection is provided on a first end of said stabilizing element; wherein said second coupling projection is provided on an opposing second end of said stabilizing element; wherein said stabilizing element including said first and second coupling projections is a continuous central tube.