An axial bearing for a high speed open-end spinning rotor mounted without axial thrust in a support disc bearing arrangement has a static magnetic bearing component secured in a bearing housing with at least two axially polarized permanent magnet rings limited by pole discs, and a dynamic magnetic bearing component having ferromagnetic webs on the rotor shaft at the spacing of the pole discs. The static magnetic bearing component ( 27 ) is arranged inside a plastic bearing bush ( 30 ) and secured by a plastic closing lid ( 31 ). The front side of the closing lid ( 31 ) has a stop journal ( 50 ) forming an axial emergency operation bearing and the rear side has a conically widened fastening lug ( 51 ) which is elastically deformed as installed.
1. An axial bearing for a spinning rotor rotated at a high rotational speed and mounted free of axial thrust in a bearing interstice of a support disc bearing arrangement of an open-end spinning device, the bearing comprising a static magnetic bearing component and a dynamic magnetic bearing component, the static magnetic bearing component being secured in a bearing housing and having at least two axially polarized permanent magnet rings limited on either side by pole discs, and the dynamic magnetic bearing component being formed by ferromagnetic webs arranged on the rotor shaft of the spinning rotor at the spacing of the pole discs, characterized in that the static magnetic bearing component ( 27 ) is arranged inside a bearing bush ( 30 ) of a plastics material and is secured by a closing lid ( 31 ) of a plastics material and in that the closing lid ( 31 ), on a front side thereof facing the static magnetic bearing component ( 27 ), has a stop journal ( 50 ) forming an axial emergency operation bearing and, on a rear side thereof, has a conically widened fastening lug ( 51 ) which is elastically deformed in the installed state.
2. An axial bearing according to claim 1 , characterized in that the closing lid ( 31 ) is produced from polyetheretherketone (PEEK).
3. An axial bearing according to claim 1 , characterized in that the closing lid ( 31 ) can be non-positively fixed in the bearing bush ( 30 ) by means of its fastening lug ( 51 ).
4. An axial bearing according to claim 1 , characterized in that the closing lid ( 31 ), on its front side, has a radial stop protection device ( 52 ) for the rotor shaft ( 4 ) of the spinning rotor ( 3 ) and in that each pole disc ( 45 ) has an internal cross-section (A) which has a larger extent in the region of a vertically arranged axis ( 40 ) in the installed state of the pole discs ( 45 ) than in the region of an axis ( 44 ) arranged orthogonally with respect to the vertical axis ( 40 ).
5. An axial bearing according to claim 4 , characterized in that the internal cross-section (A) of the pole disc ( 45 ) has the shape of an oval.
6. An axial bearing according to claim 1 , characterized in that the bearing bush ( 30 ) has, in the region of its lateral surface ( 34 ), a longitudinal groove ( 33 ) which corresponds with a guide bolt ( 32 ) projecting into a bearing bore ( 36 ) of the bearing housing ( 26 ).
7. An axial bearing according to claim 1 , characterized in that the bearing bush ( 30 ), in the region of a central receiver ( 37 ), has an end stop ring ( 38 ) and in that a guide groove ( 42 ) is arranged in the central receiver ( 37 ) and allows a precise angle positioning of the pole discs ( 45 ) of the static magnetic bearing component ( 37 ) inside the central receiver ( 37 ) of the bearing bush ( 30 ).
8. An axial bearing according to claim 7 , characterized in that each pole disc ( 45 ) has a centring lug ( 39 ) providing its installation position.
9. A static magnetic bearing component for use in an axial bearing for a spinning rotor, the static magnetic bearing component being secured in a bearing housing and having at least two axially polarized permanent magnet rings limited on either side by pole discs, characterized in that the static magnetic bearing component ( 27 ) is arranged inside a bearing bush ( 30 ) of a plastics material and is secured by a closing lid ( 31 ) of a plastics material and in that the closing lid ( 31 ), on a front side thereof facing the static magnetic bearing component ( 27 ), has a stop journal ( 50 ) forming an axial emergency operation bearing and, on a rear side thereof, has a conically widened fastening lug ( 51 ) which is elastically deformed in an installed state.