Multiple actuator pivot bearing

• US 6,490,138 B1
• Filed: 08/30/2000
• Issued: 12/03/2002
• Est. Priority Date: 08/30/2000
• Status: Expired due to Fees

• Current Assignee: Hitachi Global Storage Technologies Netherlands BV (Western Digital Corporation)
• Original Assignee: International Business Machines Corporation
• Inventors: Prater, Walter L.
• Primary Examiner(s): Tupper, Robert S.
• Application Number:
  US09/651,440
• Time in Patent Office: 825 Days
• Field of Search: 360/265.2, 360/265.4, 360/265.6, 360/294.3, 360/294.6, 360/264.4
• US Class Current: 360/294.3
• CPC Class Codes: G11B 33/08 Insulation or absorption of undesired vibrations or sounds
• CPC Class Codes: G11B 5/5521 across disk tracks spiral track following G11B5/596

Abstract

A split shaft assembly for vibration control between multiple actuator pivots in a disk storage device. A first actuator pivot is mounted on a first shaft unit and a second actuator pivot is mounted on a second shaft unit. The second shaft unit is mated to the first shaft unit in axial alignment along a common pivot axis by a separating portion of a vibration control material, which interrupts transmission of vibrational force between the first actuator pivot and the second actuator pivot.

Claims

1. A split shaft assembly for vibration control between a first actuator pivot and a second actuator pivot in a disk storage device, comprising:

a first shaft unit, wherein the first actuator pivot is mounted on said first shaft unit;

a second shaft unit, wherein the second actuator pivot is mounted on said second shaft unit; and

said second shaft unit is mated to said first shaft unit in axial alignment along a common pivot axis by a separating portion of a vibration control material, to interrupt transmission of vibrational force between the first actuator pivot and the second actuator pivot.

2. The split shaft assembly of claim 1, wherein:

said first shaft unit has a boss;

said second shaft unit has a flange; and

said vibration control material separates said flange from said boss.

3. The split shaft assembly of claim 2, wherein:

said first shaft unit includes a shoulder which said boss extends beyond and against which said flange of said second shaft unit abuts, wherein said vibration control material also extends between said flange and said shoulder.

4. The split shaft assembly of claim 1, further comprising:

a post having a first end and a second end; and

wherein;

said first shaft unit has a first recess receiving said first end of said post and said vibration control material separates said first shaft unit from said post; and

said second shaft unit has a second recess receiving said second end of said post and said vibration control material also separates said second shaft unit from said post.

5. The split shaft assembly of claim 4, wherein:

said first shaft unit includes a first bushing proximate to where said first recess receives said post;

said second shaft unit includes a second bushing proximate to where said second recess receives said post; and

said vibration control material also separates said first bushing from said second bushing, to strengthen said axial aligning of said second shaft unit with said first shaft unit along said common pivot axis.

6. The split shaft assembly of claim 4, wherein:

at least one of said first shaft unit and said second shaft unit are hollow, thereby forming at least one of said first recess and said second recess.

7. The split shaft assembly of claim 6, wherein:

both said first shaft unit and said second shaft unit are hollow, thereby forming both said first recess and said second recess;

said first end of said post extends through said first recess substantially the entire length of said first shaft unit and defines a first region between said first shaft unit and said post;

said second end of said post extends through said second recess substantially the entire length of said second shaft unit and defines a second region between said second shaft unit and said post;

said vibration control material is present in substantially all of said first region and said second region, to strengthen said axial alignment of said second shaft unit with said first shaft unit along said common pivot axis and to more strongly interrupt said transmission of vibrational force between the first actuator pivot and the second actuator pivot.

8. The split shaft assembly of claim 7, wherein:

said first shaft unit includes a first bushing proximate to where said first recess receives said post;

said second shaft unit includes a second bushing proximate to where said second recess receives said post; and

said vibration control material also separates said first bushing from said second bushing, to strengthen said axial aligning of said second shaft unit with said first shaft unit along said common pivot axis.

9. The split shaft assembly of claim 1, further comprising:

a spacer having a first opening and a second opening which are coaxial, wherein said spacer is made of said vibration control material;

and wherein;

said first shaft unit has a first end extending past the first actuator pivot;

said second shaft unit has a second end extending past the second actuator pivot; and

said first end is nested into said first opening of said spacer and said second end is nested into said second opening of said spacer and said first end is separated from contacting said second end by the presence of said spacer.

10. The split shaft assembly of claim 9, wherein:

said spacer has a first side adjacent said first opening and a second side adjacent said second opening;

said first side of said spacer abuts against the first actuator pivot; and

said second side of said spacer abuts against the second actuator pivot.

11. The split shaft assembly of claim 10, wherein:

at least one of the first actuator pivot and the second actuator pivot include a bearing race which said spacer abuts against.

12. The split shaft assembly of claim 10, wherein:

at least one of said first shaft unit and said shaft unit include a flange which said spacer abuts against.

13. The split shaft assembly of claim 1, wherein:

said first shaft unit has a first end and a first concentric bushing;

said second shaft unit has a second end and a second concentric bushing;

said first concentric bushing and said second concentric bushing are axially offset and inter-nestingly engaged along said common pivot axis, wherein said vibration control material separates said first end of said first shaft unit from said second concentric bushing and said second concentric bushing from first concentric bushing.

14. The split shaft assembly of claim 13, wherein:

said vibration control material also extends between said first end of said first shaft unit and said second end of said second shaft unit.

15. The split shaft assembly of claim 1, wherein:

said first shaft unit has a first end including a first flange;

said second shaft unit has a second end including a second flange;

said vibration control material has adhesive properties; and

said first flange and said second flange are adhesively engaged by said vibration control material.

16. The split shaft assembly of claim 1, wherein:

said vibration control material has at least one member of the set consisting of vibration isolating characteristics and vibration dampening characteristics.

17. The split shaft assembly of claim 1, wherein:

the disk storage device is a magnetic disk drive;

the first actuator is a seeking actuator; and

the second actuator is a tracking actuator.