Filter element

1. A filter element comprising a filter medium extending over an axial length between a clean air end at one end and an unfiltered air end at the opposite end, a circumferential jacket surrounding the filter medium with the filter medium being attached in a sealed manner to the jacket, and the filter medium separating an unfiltered air end from the clean air end, wherein contours are provided on the jacket for fastening the filter element in a filter housing, wherein the jacket comprises an inner ring surrounded by a coaxial outer ring spaced a radial distance therefrom, with the inner and outer rings connected across the radial space between them by a circumferential web, and axially extending ribs are arranged between the outer ring and the inner ring.

2. A filter element according to claim 1 , wherein the filter medium is a wound filter medium or an extruded filter medium.

3. A filter element according to claim 1 , wherein the jacket comprises a fusion zone to which a circumferential edge at an end of the filter medium is fused such that the filter medium is attached in a sealed manner to the jacket.

4. A filter element comprising a filter medium extending over an axial length between a clean air end at one end and an unfiltered air end at the opposite end, a circumferential jacket surrounding the filter medium with the filter medium being attached in a sealed manner to the jacket, and the filter medium separating an unfiltered air end from the clean air end, wherein contours are provided on the jacket for fastening the filter element in a filter housing, wherein movable latches are arranged on the jacket for facilitating a form-fitting, detachable connection to a flange at the clean air end, wherein the movable latches comprise catches which are pivotably connected to the jacket by film hinges, and claws with facing flanks are arranged on the catches such that in a latched state the catches clamp a cam member on the jacket to a bulge on the flange at the clean air end, with the flanks of the claws urging the flange and jacket against each other under compression so that the film hinge is not subjected to stress, and wherein the movable latches are pivotable such that the catches can be oriented approximately perpendicular to the axis of the jacket and the claws are oriented approximately parallel to the axis of the jacket.

5. A filter element according to claim 4 , wherein the filter medium is a wound filter medium or an extruded filter medium.

6. A filter element according to claim 4 , wherein the jacket comprises a fusion zone to which a circumferential edge at an end of the filter medium is fused such that the filter medium is attached in a sealed manner to the jacket.

7. A filter element comprising a filter medium extending over an axial length between a clean air end at one end and an unfiltered air end at the opposite end, a circumferential jacket surrounding the filter medium with the filter medium being attached in a sealed manner to the jacket, and the filter medium separating an unfiltered air end from the clean air end, wherein contours are provided on the jacket for fastening the filter element in a filter housing, wherein the jacket has an elastic sealing contour at the clean air end, said sealing contour being produced in one piece with the jacket and forming a tight connection between the jacket and a flange at the clean air end, and the jacket has supporting contour which communicates with an annular contact surface of the flange at the clear air end, said supporting contour of the jacket comprising a radial supporting shoulder that communicates with an annular shoulder on the flange, and the flange is disposed at the clean air end of a clean air tube.

8. A filter element according to claim 7 , wherein the filter medium is a wound filter medium or an extruded filter medium.

9. A filter element according to claim 7 , wherein the jacket comprises a fusion zone to which a circumferential edge at an end of the filter medium is fused such that the filter medium is attached in a sealed manner to the jacket.

10. A filter element comprising a filter medium extending over an axial length between a clean air end at one end and an unfiltered air end at the opposite end, a circumferential jacket surrounding the filter medium with the filter medium being attached in a sealed manner to the jacket, and the filter medium separating an unfiltered air end from the clean air end, wherein contours are provided on the jacket for fastening the filter element in a filter housing, wherein the jacket of the filter element is provided with recesses which receive detent noses formed on a filter housing such that the detent noses on the filter housing latch in the recesses and thereby attach filter housing to the filter element.

11. A filter element according to claim 10 , wherein the filter medium is a wound filter medium or an extruded filter medium.

12. A filter element according to claim 10 , wherein the jacket comprises a fusion zone to which a circumferential edge at an end of the filter medium is fused such that the filter medium is attached in a sealed manner to the jacket.