Folded fluid channel for a fluid dynamic bearing motor

Patent metadata

Field	Value
Publication number	US-9366289-B2
Application number	US-201414158585-A
Country	US
Kind code	B2
Filing date	Jan 17, 2014
Priority date	May 8, 2008
Publication date	Jun 14, 2016
Grant date	Jun 14, 2016

Abstract

An apparatus includes a stationary shaft and a sleeve rotatable with respect to the shaft. A fluid dynamic bearing is defined by the stationary shaft and the sleeve. A fluid channel includes a first axially extending portion in the fluid dynamic bearing, and a radially extending portion extending radially outward from the first axially extending portion. In addition the fluid channel includes a second axially extending portion extending axially downward from the radially extending portion. The apparatus further includes a pump seal including grooves formed in the second axially extending portion.

First claim

The invention claimed is:

1. An apparatus comprising:
a stationary shaft;
a sleeve rotatable with respect to the shaft;
a fluid dynamic bearing defined by the stationary shaft and the sleeve;
a fluid channel including,
a first axially extending portion in the fluid dynamic bearing,
a radially extending portion extending radially outward from the first axially extending portion, and
a second axially extending portion extending axially downward from the radially extending portion, wherein the first axially extending portion and the second axially extending portion are both defined by a stationary component and a rotatable component; and

a pump seal including grooves formed in the second axially extending portion.

2. The apparatus of claim 1 , further comprising a capillary seal radially outside of the second axially extending portion, wherein the pump seal and the capillary seal are at opposite axial ends of the fluid channel.

3. The apparatus of claim 1 , wherein the pump seal, a capillary seal, and the fluid dynamic bearing are positioned axially below the radially extending portion.

4. The apparatus of claim 1 , further comprising a thrust bearing defined by the sleeve and a base cup.

5. The apparatus of claim 1 , further comprising a recirculation passageway including,
a first end radially inside of the pump seal, and
a second end radially outside of a thrust bearing, wherein the thrust bearing is defined by the sleeve and a base.

6. The apparatus of claim 1 , wherein the fluid channel is defined by opposing rotatable and stationary surfaces.

7. The apparatus of claim 1 , wherein the second axially extending portion does not extend above the fluid dynamic bearing.

8. An apparatus comprising:
a stationary component including a shaft;
a rotatable component;
a fluid dynamic bearing defined by the stationary component and the rotatable component;
a fluid channel including a grooved pump seal;
a first portion of the fluid channel, wherein the first portion is axially above the fluid dynamic bearing and extending radially outward from the shaft;
a second portion of the fluid channel, wherein the second portion is radially outside of the fluid dynamic bearing and extends axially downward from the first portion, wherein the first portion and the second portion are both defined by the stationary component and the rotatable component; and
a recirculation passageway including,
a first end radially inside of the grooved pump seal, and
a second end radially outside of a thrust bearing, wherein the thrust bearing is defined by the rotatable component and the stationary component.

9. The apparatus of claim 8 , further comprising a capillary seal radially outside of the second portion, wherein the grooved pump seal and the capillary seal are at opposite axial ends of the fluid channel.

10. The apparatus of claim 8 , wherein the grooved pump seal, a capillary seal, and the fluid dynamic bearing are positioned axially below the first portion.

11. The apparatus of claim 8 , further comprising a thrust bearing defined by the rotatable component and the stationary component.

12. The apparatus of claim 8 , wherein the fluid channel is defined by opposing rotatable and stationary surfaces.

13. The apparatus of claim 8 , wherein the second portion does not extend above the fluid dynamic bearing.

14. An apparatus comprising:
a stationary component including a shaft;
a rotatable component;
a fluid dynamic bearing defined by the stationary component and the rotatable component;
a grooved pump seal at a first axial end of the rotatable component and defined by the stationary component and the rotatable component, wherein the grooved pump seal does not extend axially beyond the fluid dynamic bearing;
a thrust bearing at a second axial end of the rotatable component and defined by the stationary component and the rotatable component; and
a recirculation passageway including,
a first end radially inside of the grooved pump seal, and
a second end radially outside of a thrust bearing, wherein the thrust bearing is defined by the rotatable component and the stationary component.

15. The apparatus of claim 14 , further comprising a capillary seal radially outside of the grooved pump seal, wherein the grooved pump seal and the capillary seal are at opposite axial ends of the rotatable component.

16. The apparatus of claim 14 , wherein the grooved pump seal, a capillary seal, and the fluid dynamic bearing are positioned axially below a radial fluid channel.

17. The apparatus of claim 14 , wherein the thrust bearing defined by a stationary base cup and a rotatable sleeve.

18. The apparatus of claim 14 , a fluid channel defined by opposing rotatable and stationary surfaces, wherein the fluid channel includes the grooved pump seal.

19. An apparatus comprising:
a fluid dynamic bearing system defined by a stationary component including a shaft and a rotatable component;
a grooved pump seal at a first end of the fluid dynamic bearing system;
a capillary seal at a second end of the fluid dynamic bearing system, wherein the capillary seal is formed on an axially extending channel between the stationary component and the rotatable component;
a first stationary cup at a first axial end of the shaft;
a second stationary cup at a second axial end of the shaft, wherein concave ends of both the first and second stationary cup face each other; and
a recirculation passageway including,
a first end radially inside of a pump seal, and
a second end radially outside of a thrust bearing, wherein the thrust bearing is defined by the second stationary cup and a sleeve.

20. The apparatus of claim 19 further comprising a journal bearing, wherein the journal bearing and the grooved pump seal occupy the same axial space.

21. The apparatus of claim 19 , wherein the grooved pump seal, the capillary seal, and the fluid dynamic bearing system are positioned between the concave ends.

22. The apparatus of claim 19 , further comprising a thrust bearing defined by the stationary component and the rotatable component.

23. The apparatus of claim 19 wherein,
the first stationary cup and the shaft are a single unitary component, or
the second stationary cup and the shaft are a single unitary component.

24. An apparatus comprising:
a fluid channel defined by a stationary component including a shaft and a rotatable component, wherein the stationary component and the rotatable component are configured to form a grooved pump seal at a first end of the fluid channel;
a capillary seal at a second end of the fluid channel, wherein the capillary seal is formed on an axially extending channel between the stationary component and the rotatable component;
a first stationary cup at a first axial end of the shaft;
a second stationary cup at a second axial end of the shaft, wherein concave ends of both the first and second stationary cup face each other; and
a recirculation passageway including,
a first end radially inside of the grooved pump seal, and
a second end radially outside of a thrust bearing, wherein the thrust bearing is defined by the stationary component and the rotatable component.

25. The apparatus of claim 24 further comprising a journal bearing, wherein the journal bearing and the grooved pump seal occupy the same axial space.

26. The apparatus of claim 24 , wherein the grooved pump seal, the

Assignees

• Seagate Technology Llc

Inventors

• Le Lynn B
• Grantz Alan Lyndon

Classifications

• F16C32/0633 Primary

  the liquid being retained in a gap · CPC title

• F16C41/008

  Identification means, e.g. markings, RFID-tags; Data transfer means · CPC title

• F16C2370/12

  Hard disk drives or the like · CPC title

• F16C17/105

  with at least one bearing surface providing angular contact, e.g. conical or spherical bearing surfaces · CPC title

• F16C17/107

  with at least one surface for radial load and at least one surface for axial load · CPC title