Fluid pumping capillary seal for a fluid dynamic bearing
An apparatus is provided including a shaft, wherein the shaft is stationary. A rotatable component is configured to rotate with respect to the shaft. A fluid is operable to flow between the shaft and the rotatable component. A limiter is at a first axial end of the shaft, and a cup is at a second axial end of the shaft. An axially extending grooved region is between the limiter and the rotatable component.
1. An apparatus comprising:
a shaft, wherein the shaft is stationary;
a rotatable component configured to rotate with respect to the shaft;
a fluid operable to flow between the shaft and the rotatable component;
a limiter at a first axial end of the shaft;
a cup at a second axial end of the shaft; and
an axially extending grooved region between the limiter and the rotatable component.
2. The apparatus of claim 1 , wherein
the grooved region includes a first end and a second end, and
a width of a groove at the first end is different than a width at the second end.
3. The apparatus of claim 1 , wherein the grooved region increasingly diverges.
4. The apparatus of claim 1 further comprising a radially extending grooved region between the limiter and the rotatable component.
5. The apparatus of claim 1 , wherein the axially extending grooved region is formed on the limiter.
6. The apparatus of claim 1 further comprising a capillary seal between the cup and the rotatable component.
7. The apparatus of claim 1 wherein the rotatable component includes a sleeve and a hub.
8. An apparatus comprising:
an axially extending groove in a limiter; and
a rotatable component configured to rotate with respect to the limiter;
wherein the axially extending groove and the rotatable component are configured to pump a fluid from a first axial end of the rotatable component towards a second axial end of the rotatable component.
9. The apparatus of claim 8 , wherein
the groove includes a first end and a second end, and
a width of the groove at the first end is different than a width at the second end.
10. The apparatus of claim 8 , wherein the groove increasingly diverges.
11. The apparatus of claim 8 further comprising a radially extending groove in the limiter.
12. The apparatus of claim 8 , further comprising a cup positioned at the second axial end of the rotatable component.
13. The apparatus of claim 12 further comprising a capillary seal between the cup and the rotatable component.
14. The apparatus of claim 8 wherein the rotatable component includes a sleeve and a hub.
15. An apparatus comprising:
an axially extending grooved region at a first axial end of a stationary component;
a cup at a second axial end of the stationary component;
a thrust bearing at the first axial end of the stationary component, wherein the thrust bearing is between the axially extending grooved region and the cup;
a rotatable component configured to rotate with respect to the cup; and
a capillary seal between the cup and the rotatable component.
16. The apparatus of claim 15 , wherein
the grooved region includes a first end and a second end, and
a width of a groove at the first end is different than a width at the second end.
17. The apparatus of claim 15 , wherein the grooved region increasingly diverges.
18. The apparatus of claim 15 further comprising a radially extending grooved region at the first axial end of the stationary component.
19. The apparatus of claim 15 , wherein the axially extending grooved region is formed on a limiter.
20. The apparatus of claim 15 wherein the rotatable component includes a sleeve and a hub.