Bearing positioning member for a spindle motor

• US 20040228559A1
• Filed: 05/13/2003
• Published: 11/18/2004
• Est. Priority Date: 05/13/2003
• Status: Active Grant

• Current Assignee: Sunonwealth Electric Machine, Ind. Co., Ltd.
• Original Assignee: Sunonwealth Electric Machine, Ind. Co., Ltd.
• Inventors: Horng, Alex, Hong, Ching-Sheng, Horng, Yin-Rong
• Granted Patent: US 7,070,336 B2
• Time in Patent Office: Days
• US Class Current: 384/517
• CPC Class Codes: F16C 25/08 self-adjusting

Abstract

A conic bearing positioning member for a spindle motor includes a small diameter portion abutting against an inner race of a ball bearing of the spindle motor, a large diameter portion abutting against a rotor of the spindle motor, and at least one resilient connecting portion extending between the small diameter portion and the large diameter portion for biasing the ball bearing and the rotor away from each other, assuring a gap between the ball bearing and the rotor. The conic bearing positioning member may be a helical spring.

Claims

1. A bearing positioning member for a spindle motor, the bearing positioning member being conic and comprising:

a small diameter portion adapted to abut against an inner race of a ball bearing of the spindle motor;

a large diameter portion adapted to abut against a rotor of the spindle motor; and

at least one resilient connecting portion extending between the small diameter portion and the large diameter portion for biasing the ball bearing and the rotor away from each other, assuring a gap between the ball bearing and the rotor.

2. The bearing positioning member as claimed in claim 1, wherein the small diameter portion is a ring, said at least one connecting portion being a plurality of resilient legs extending radially upward and outward from the ring, with each said resilient leg having a distal end that has a bent portion to form the large diameter portion.

3. The bearing positioning member as claimed in claim 1, wherein the small diameter portion is a first ring, the large diameter portion being a second ring having a diameter greater than that of the first ring, said at least one connecting portion being a plurality of resilient legs extending radially upward and outward from the first ring, with each said resilient leg having a distal end connected to the second ring.

4. The bearing positioning member as claimed in claim 2, wherein each said resilient leg is arcuate.

5. The bearing positioning member as claimed in claim 3, wherein each said resilient leg is arcuate.

6. The bearing positioning member as claimed in claim 1, wherein the small diameter portion is punched to form a plurality of protrusions for contacting with an outer end face of the inner race of the ball bearing, thereby reducing a contact area between the ball bearing and the small diameter portion.

7. The bearing positioning member as claimed in claim 2, wherein the small diameter portion is punched to form a plurality of protrusions for contacting with the outer end face of the inner race of the ball bearing, thereby reducing a contact area between the ball bearing and the small diameter portion.

8. The bearing positioning member as claimed in claim 3, wherein the small diameter portion is punched to form a plurality of protrusions for contacting with the outer end face of the inner race of the ball bearing, thereby reducing a contact area between the ball bearing and the small diameter portion.

9. The bearing positioning member as claimed in claim 1, wherein the bearing positioning member is a helical spring, with the small diameter portion being the smallest coil of the helical spring, with the large diameter portion being the largest coil of the helical spring, and with said at least one connecting portion being intermediate coils of the helical spring.

10. The bearing positioning member as claimed in claim 1, the rotor includes a recessed portion on an inner side thereof, the recessed portion having a bottom wall to which the large diameter portion abuts against.

11. The bearing positioning member as claimed in claim 1, with the ball bearing being adapted to be mounted in an axle tube, the axle tube having an inner flange for mounting and positioning the ball bearing.

12. A bearing positioning member for a spindle motor, the bearing positioning member being a helical spring having a smallest coil abutting against an inner race of a ball bearing of the spindle motor, the helical spring further having a largest coil abutting against an inner side of a rotor of the spindle motor.

13. A spindle motor comprising:

a rotor having an inner side;

a ball bearing adapted to be mounted in an axle tube; and

a conic bearing positioning member including a small diameter portion abutting against an inner race of the ball bearing, a large diameter portion abutting against the inner side of the rotor, and at least one resilient connecting portion extending between the small diameter portion and the large diameter portion for biasing the ball bearing and the rotor away from each other, assuring a gap between the ball bearing and the rotor.

14. The spindle motor as claimed in claim 13, wherein the small diameter portion is a ring, said at least one connecting portion being a plurality of resilient legs extending radially upward and outward from the ring, with each said resilient leg having a distal end that has a bent portion to form the large diameter portion.

15. The spindle motor as claimed in claim 13, wherein the small diameter portion is a first ring, the large diameter portion being a second ring having a diameter greater than that of the first ring, said at least one connecting portion being a plurality of resilient legs extending radially upward and outward from the first ring, with each said resilient leg having a distal end connected to the second ring.

16. The spindle motor as claimed in claim 14, wherein each said resilient leg is arcuate.

17. The spindle motor as claimed in claim 15, wherein each said resilient leg is arcuate.

18. The bearing positioning member as claimed in claim 13, wherein the small diameter portion is punched to form a plurality of protrusions for contacting with an outer end face of the inner race of the ball bearing, thereby reducing a contact area between the ball bearing and the small diameter portion.

19. The bearing positioning member as claimed in claim 13, wherein the inner side of the rotor includes a recessed portion having a bottom wall to which the large diameter portion abuts against.

20. The bearing positioning member as claimed in claim 13, wherein the axle tube has an inner flange for mounting and positioning the ball bearing.