Spindle regions
According to various embodiments of the invention, a motor with a rotatable hub having fluid dynamic journal and thrust bearings can be assembled from four major components: a spindle, a hub, a thrust washer, and a base. The spindle can integrate journal bearing, axial limiter, and ring seal functions. The hub can integrate journal bearing, thrust bearing, ring seal, axial limiter, capillary seal, and bumper functions. The thrust washer can integrate thrust bearing and lubricant circulation functions. The base can integrate capillary seal and lubricant storage and circulation functions. Each function can be integrated as structural feature in its corresponding component. The spindle, hub, and thrust bearing can be preassembled. The base can be loaded with lubricant prior to assembly with the spindle/hub/thrust bearing combination.
1. An apparatus comprising:
a spindle including:
a larger diameter first region adjacent a spindle first end;
a smaller diameter second region adjacent a spindle second end; and
a shoulder extending between the larger diameter first region and the smaller diameter second region;
a hub including:
an inward protruding annular shoulder adjacent a hub end;
an inner hub opening, wherein
the inner hub opening is operable to permit passage therethrough by the smaller diameter second region, and
the inner hub opening is operable to block passage therethrough by the larger diameter first region; and
a thrust washer between the hub and a base, wherein the hub rotates relative to the base, and wherein the thrust washer defines a central opening sized to fit a portion of the smaller diameter second region.
2. The apparatus of claim 1 , further comprising a fluid dynamic journal bearing pattern formed in at least a portion of the hub facing the larger diameter first region.
3. The apparatus of claim 2 , wherein the journal bearing pattern is configured to pump a lubricating fluid toward the spindle second end.
4. The apparatus of claim 3 , further comprising a fluid dynamic thrust bearing pattern formed in a surface of the thrust washer.
5. The apparatus of claim 4 , wherein the thrust bearing pattern is configured to pump the lubricating fluid toward the smaller diameter second region.
6. The apparatus of claim 5 , wherein the central opening of the thrust washer is configured to form a gap with the smaller diameter second region.
7. The apparatus of claim 6 , wherein the hub and the base define a capillary seal.
8. The apparatus of claim 7 , wherein the thrust bearing pattern is further configured to pump fluid toward the capillary seal.
9. The apparatus of claim 1 , further comprising a bumper formed in the hub.
10. The apparatus of claim 1 , further comprising a radial ring seal formed in facing surfaces of the larger diameter first region and the hub.
11. The apparatus of claim 1 , further comprising a plurality of electromagnets annularly disposed on the base, coaxial with an axis between the spindle first end and the spindle second end, and a plurality of permanent magnets annularly disposed on the hub, facing the plurality of electromagnets, wherein the electromagnets are configured for activation to cause the hub to rotate relative to the base.
12. An assembly comprising:
a spindle including:
a spindle first end;
a first region adjacent the spindle first end;
a spindle second end; and
a second region adjacent the spindle second end, wherein the second region has a smaller diameter than the first region;
a hub defining an inner sleeve sized to receive the spindle and to permit rotation of the hub about the spindle, wherein the inner sleeve includes:
an inner sleeve first end;
an inner sleeve second end; and
an inward protruding annular shoulder adjacent the inner sleeve first end, wherein
the inward protruding annular shoulder defines an inner hub opening, and
the inner hub opening is sized to permit passage therethrough by the
second region of the spindle, and to prevent passage therethrough by the first region of the spindle;
a base defining an outer sleeve, wherein
wherein the hub rotates relative to the base,
the outer sleeve includes an inner surface sized to receive the inner sleeve,
the outer sleeve permits rotation of the inner sleeve therein, and
the outer sleeve defines a central hole sized to receive the spindle second end; and a thrust washer between the hub and the base, wherein
a central opening in the thrust washer, wherein the central opening is defined by the thrust washer, and wherein further the central opening is sized to fit the smaller diameter of the second region, and
the thrust washer further defines a gap operable to permit flow of lubricating fluid between the inner sleeve and the outer sleeve.
13. The assembly of claim 12 , further comprising a fluid dynamic journal bearing pattern formed in at least a portion of the inner sleeve facing the first region of the spindle.
14. The assembly of claim 13 , wherein the journal bearing pattern is configured to pump the lubricating fluid toward the spindle second end.
15. The assembly of claim 12 , further comprising a fluid dynamic thrust bearing pattern formed in a surface of the thrust washer proximate to the inward protruding annular shoulder of the hub.
16. The assembly of claim 15 , wherein the fluid dynamic thrust bearing pattern is configured to pump the lubricating fluid toward the second region of the spindle.
17. The assembly of claim 16 , wherein the fluid dynamic thrust bearing pattern is further configured to pump fluid toward a capillary seal through the gap.
18. The assembly of claim 12 , wherein the central opening of the thrust washer is configured to form a gap with the second region of the spindle.
19. The assembly of claim 12 , further comprising a bumper formed in at least a portion of the inner sleeve of the hub.
20. The assembly of claim 12 , further comprising a radial ring seal formed in facing surfaces of the first region of the spindle and the inner sleeve of the hub.
21. The assembly of claim 12 , further comprising a plurality of electromagnets annularly disposed on the base, coaxial with an axis between the spindle first end and the spindle second end, and a plurality of permanent magnets annularly disposed on the hub, facing the plurality of electromagnets, wherein the plurality of electromagnets are configured for activation to cause the hub to rotate relative to the base.