Claims
- 1. A bearing comprising:
a fluid dynamic conical bearing; and a pivot bearing.
- 2. a bearing according to claim 1 further comprising:
a fluid dynamic journal bearing.
- 3. A bearing comprising:
a sleeve having a plurality of sections forming a cavity within said sleeve, a shaft having a plurality of sections; and a fluid; wherein
said shaft extends into said cavity within said sleeve, and a gap exists between said shaft and said sleeve; said fluid is contained in said gap; a first section of said plurality of sections of said sleeve has a length extending from a second section of said plurality of sections of said sleeve, and it has an inner radius perpendicular to said length that increases as a function of a distance measured along said length from said second section of said plurality of sections of said sleeve; a first section of said plurality of sections of said shaft has a length extending from a second section of said plurality of sections of said shaft, and it has a radius perpendicular to said length that increases as a function of a distance measured along the length from said second section of said plurality of sections of said shaft; said first section of said plurality of sections of said shaft is positioned inside said first section of said plurality of sections of said sleeve; pressure generating grooves are formed on one of said first section of said plurality of sections of said sleeve and said first section of said plurality of sections of said shaft; a third section of said plurality of sections of said shaft has a length extending from said first section of said plurality of sections of said shaft and it has a radius perpendicular to said length that decreases as a function of a distance measured along the length from said first section of said plurality of sections of said shaft until said radius of said third section of said shaft reaches zero at the end of said length; the third section of said plurality of sections of said shaft is positioned inside a third section of said plurality of sections of said sleeve.
- 4. A bearing according to claim 3 wherein:
said shaft rotates.
- 5. A bearing according to claim 3 wherein:
said sleeve rotates.
- 6. A bearing according to claim 3 further comprising:
an end plate inserted into a fourth section of said plurality of sections of said sleeve; wherein
said fourth section of said plurality of sections of said sleeve is contiguous with said third section of said plurality of sections of said sleeve and forms an opening at the bottom end of said cavity within said sleeve; said endplate seals said opening; and said shaft rotates on said endplate.
- 7. A bearing according to claim 3 wherein:
the inner radius of said first section of said plurality of sections of said sleeve has a minimum value and it is described by the following equation: rsl1=A+mY where
rsl1 is the inner radius of said first section of said plurality of sections of said sleeve at a particular point along its length; A is the minimum value of the inner radius of said first section of said plurality of sections of said sleeve; m is a constant positive value, and Y is a distance measured from said second section of said plurality of sections of said sleeve to said particular point.
- 8. A bearing according to claim 7 wherein:
the radius of the first section of said plurality of sections of said shaft has a minimum value and it is described by the equation: rsh1=D+f(Z); where
rsh1 is the radius of the first section of said plurality of sections of said shaft at a particular point along its length; D is the minimum value of the radius of the first section of said plurality of sections of said shaft; Z is a distance measured from said second section of said plurality of sections of said shaft to said particular point; f(Z) is a function of Z with a minimum value of zero; the derivative of f(Z) with respect to Z is always positive; and the second derivative of f(Z) with respect to Z is always negative.
- 9. A bearing according to claim 3 wherein:
the distance between the radius of said first section of said plurality of sections of said shaft and the inner radius of said first section said plurality of sections of said sleeve is constant over the entire length of said shaft.
- 10. A bearing according to claim 9 wherein:
the inner radius of said first section of said plurality of sections of said sleeve has a minimum value and it is described by the following equation: rsl1=A+mY where
rsl1 is the inner radius of said first section of said plurality of sections of said sleeve at a particular point along its length; A is the minimum value of the inner radius of said first section of said plurality of sections of said sleeve; m is a constant positive value, and Y is a distance measured from said second section of said plurality of sections of said sleeve to said particular point.
- 11. A bearing according to claim 9 wherein:
the radius of the first section of said plurality of sections of said shaft has a minimum value and it is described by the equation: rsh1=D+f(Z); where
rsh1 is the radius of the first section of said plurality of sections of said shaft at a particular point along its length; D is the minimum value of the radius of the first section of said plurality of sections of said shaft; Z is a distance measured from said second section of said plurality of sections of said shaft to said particular point; f(Z) is a function of Z with a minimum value of zero; the derivative of f(Z) with respect to Z is always positive; and the second derivative of f(Z) with respect to Z is always negative.
- 12. A spindle motor comprising:
a stator; a rotor; a fluid dynamic conical bearing; and a pivot bearing.
- 13. A bearing for a spindle motor comprising:
a shaft having an end; a bearing sleeve having a cavity that surrounds the shaft at a small radial distance; and an endplate inserted into an opening in said cavity and affixed to the bearing sleeve; wherein
a pivot bearing is provided between the endplate and the end of the shaft; a portion of said cavity is cone shaped; and a portion of said shaft is shaped in a complimentary fashion to said cone shaped portion of said cavity.
Priority Claims (1)
Number |
Date |
Country |
Kind |
DE10239886.0 |
Aug 2002 |
DE |
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from Fed. Rep. Of Germany Patent Application No. DE10239886.0, filed on Aug. 29, 2002, and from U.S. Provisional Patent Application Serial No. 60/363,784, filed on Mar. 12, 2002.
Provisional Applications (1)
|
Number |
Date |
Country |
|
60363784 |
Mar 2002 |
US |