Pivot attach method for disk drive actuator using taper lock shims
View Patent ↗Various methods and apparatus relating to disk drive actuators and methods of manufacturing them are disclosed and claimed. In certain embodiments, a disk drive actuator assembly comprises a pivot bearing defining a pivot bearing rotational axis; an actuator arm including a bore, the pivot bearing disposed at least partially within the bore; a first tapered shim, interposed in the bore between the pivot bearing and the actuator arm, the first tapered shim having a thickness at a first end greater than a thickness at a second end; and a second tapered shim, interposed in the bore between the pivot bearing and the actuator arm, the second tapered shim having a thickness at a third end greater than a thickness at a fourth end; wherein the second tapered shim frictionally engages the first tapered shim to hold the pivot bearing substantially in place relative to the actuator arm.
1. A disk drive actuator assembly comprising:
a pivot bearing defining a pivot bearing rotational axis;
an actuator arm including a bore, the pivot bearing disposed at least partially within the bore;
a first tapered shim, interposed in the bore between the pivot bearing and the actuator arm, the first tapered shim having a thickness at a first end greater than a thickness at a second end;
a second tapered shim, interposed in the bore between the pivot bearing and the actuator arm, the second tapered shim having a thickness at a third end greater than a thickness at a fourth end;
wherein the second tapered shim frictionally engages the first tapered shim to hold the pivot bearing substantially in place relative to the actuator arm.
2. The disk drive actuator assembly of claim 1 , wherein the first tapered shim forms an outer housing of the pivot bearing to form a tapered pivot bearing cartridge.
3. The disk drive actuator assembly of claim 1 , wherein the second tapered shim forms an inner housing of the actuator arm to form a tapered actuator bore.
4. The disk drive actuator assembly of claim 1 , wherein the first tapered shim is substantially cylindrical.
5. The disk drive actuator assembly of claim 4 , wherein the first tapered shim is a substantially right circular cylinder.
6. The disk drive actuator assembly of claim 4 , wherein the second tapered shim is substantially cylindrical.
7. The disk drive actuator assembly of claim 6 , wherein the second tapered shim is a substantially right circular cylinder.
8. The disk drive actuator assembly of claim 1 , wherein the first tapered shim is split to form a gap between a first edge that is substantially parallel to the pivot bearing rotational axis, and a second edge that is substantially parallel to the pivot bearing rotational axis.
9. The disk drive actuator assembly of claim 8 , wherein the second tapered shim is split to form a gap between a third edge that is substantially parallel to the pivot bearing rotational axis, and a fourth edge that is substantially parallel to the pivot bearing rotational axis.
10. The disk drive actuator assembly of claim 1 , wherein the first end is a lower axial extent and the second end is an upper axial extent.
11. The disk drive actuator assembly of claim 10 , wherein the third end is an upper axial extent and the fourth end is a lower axial extent.
12. The disk drive actuator assembly of claim 8 , wherein the first end is a first circumferential extent that includes the first edge and the second end is a second circumferential extent that includes the second edge.
13. The disk drive actuator assembly of claim 9 , wherein the third end is a third circumferential extent that includes the third edge and the fourth end is a fourth circumferential extent that includes the fourth edge.
14. The disk drive actuator assembly of claim 1 , wherein the thickness of the first tapered shim varies substantially linearly from the first end to the second end.
15. The disk drive actuator assembly of claim 14 , wherein the thickness of the second tapered shim varies substantially linearly from the third end to the fourth end.
16. The disk drive actuator assembly of claim 1 , wherein the thickness at the first end is in the range of about 230 microns to about 900 microns.
17. The disk drive actuator assembly of claim 1 , wherein the thickness at the third end is in the range of about 230 microns to about 900 microns.
18. The disk drive actuator assembly of claim 1 , wherein the thickness at the second end is in the range of about 25 microns to about 180 microns.
19. The disk drive actuator assembly of claim 1 , wherein the thickness at the fourth end is in the range about 25 microns to about 180 microns.
20. The disk drive actuator assembly of claim 1 , wherein the first tapered shim comprises a first inner surface in frictional contact with at least a portion of the pivot bearing and a first outer surface defining a first taper angle with respect to the first inner surface, wherein the first outer surface is in frictional contact with at least a portion of the second tapered shim.
21. The disk drive actuator assembly of claim 20 , wherein the second tapered shim comprises a second outer surface in frictional contact with at least a portion of the bore and a second inner surface defining a second taper angle with respect to the second outer surface, wherein the second inner surface is in frictional contact with at least a portion of the first outer surface of the first tapered shim.
22. The disk drive actuator assembly of claim 21 , wherein the first taper angle is substantially equal to the second taper angle.
23. The disk drive actuator assembly of claim 20 , wherein the first outer surface includes at least one raised portion for frictionally engaging the second inner surface.
24. A method of fabricating a disk drive actuator assembly, comprising
providing a pivot bearing defining a pivot bearing rotational axis;
providing an actuator arm including a bore;
disposing at least a portion of the pivot bearing within the bore;
inserting at least a portion of a first tapered shim into the bore between the pivot bearing and the actuator arm, the first tapered shim having a thickness at a first end greater than a thickness at a second end; and
inserting at least a portion of a second tapered shim into the bore between the pivot bearing and the actuator arm, the second tapered shim having a thickness at a third end greater than a thickness at a fourth end, such that the second tapered shim frictionally engages the first tapered shim to hold the pivot bearing substantially in place relative to the actuator arm.
25. The method of claim 23 , wherein the first tapered shim is split to form a gap between a first edge that is substantially parallel to the pivot bearing rotational axis and a second edge that is substantially parallel to the pivot bearing rotational axis.
26. The method of claim 23 , wherein the first end is a lower axial extent and the second end is an upper axial extent.
27. The method of claim 25 , wherein inserting at least a portion of a second tapered shim into the bore comprises applying a force on the second tapered shim substantially parallel to the pivot bearing rotational axis.
28. The method of claim 24 , wherein the first end is a first circumferential extent that includes the first edge and the second end is a second circumferential extent that includes the second edge.
29. The method of claim 27 , wherein inserting at least a portion of a second tapered shim into the bore comprises applying a substantially tangential force to the second tapered shim to frictionally engage the first tapered shim.
30. The method of claim 28 , wherein the second tapered shim further comprises a raised tab for applying the substantially tangential force.
31. The method of claim 23 , wherein the first tapered shim forms an outer housing of the pivot bearing to form a tapered pivot bearing cartridge.
32. The method of claim 23 , wherein the second tapered shim forms an inner housing of the actuator arm to form a tapered actuator bore.