Uncoupled piezoelectric milli-actuator assembly

1. An actuator arm assembly for a hard-disk drive (HDD) comprising:

an actuator arm comprising a well; and

a piezoelectric element disposed within said well wherein said piezoelectric element is aligned with a neutral axis of said actuator arm, wherein said piezoelectric element is coupled with a first vertical surface of said well and wherein said well further comprises:

at least one projection of said actuator arm which projects into said well from said first vertical surface and which conveys force from said piezoelectric element to said actuator arm when said piezoelectric element is actuated.

2. The actuator arm assembly of claim 1 wherein said piezoelectric element is coupled with said first vertical surface of said well using a viscoelastic adhesive.

3. The actuator arm assembly of claim 1 wherein said piezoelectric element is not coupled with a top surface of said well and has freedom of motion relative to said top surface of said well.

4. The actuator arm assembly of claim 1 wherein a neutral axis of said piezoelectric element is aligned with an estimated neutral axis of said actuator arm coupled with said piezoelectric element.

5. The actuator arm assembly of claim 1 wherein a central axis of said piezoelectric element is aligned with said neutral axis of said actuator arm.

6. The actuator arm assembly of claim 1 wherein said piezoelectric element comprises a first piezoelectric actuator and a second piezoelectric actuator.

7. A disk drive comprising:

at least one data storage disk rotatably mounted in said disk drive; and

a rotary actuator comprising at least one actuator arm and a load beam coupled with said at least one actuator arm, said at least one actuator arm further comprising a well and a piezoelectric element disposed within said well wherein said piezoelectric element is aligned with a neutral axis of said actuator arm, wherein said piezoelectric element is coupled with a first vertical surface of said well, wherein said well further comprises:

at least one projection of said actuator arm which projects into said well from said first vertical surface and which conveys force from said piezoelectric element to said actuator arm when said piezoelectric element is actuated.

8. The disk drive of claim 7 wherein said piezoelectric element is coupled with said first vertical surface of said well using a viscoelastic adhesive.

9. The disk drive of claim 7 wherein said piezoelectric element is not coupled with a top surface of said well and has freedom of motion relative to said top surface of said well.

10. The disk drive of claim 7 wherein a neutral axis of said piezoelectric element is aligned with an estimated neutral axis of said actuator arm coupled with said piezoelectric element.

11. The disk drive of claim 7 wherein a central axis of said piezoelectric element is aligned with said neutral axis of said actuator arm.

12. The disk drive of claim 7 wherein said piezoelectric element comprises a first piezoelectric actuator and a second piezoelectric actuator.

13. A hard-disk drive (HDD) including an actuator arm configured with a milli-actuator assembly, said HDD comprising:

a magnetic-recording disk;

a disk enclosure comprising a disk-enclosure base;

a spindle motor affixed in said disk-enclosure base, for rotating said magnetic-recording disk;

an actuator arm configured with a well and a piezoelectric element disposed within said well wherein said piezoelectric element is aligned with a neutral axis of said actuator arm and wherein said piezoelectric element is coupled with a first vertical surface of said well, wherein said well further comprises:

at least one projection of said actuator arm which projects into said well from said first vertical surface and which conveys force from said piezoelectric element to said actuator arm when said piezoelectric element is actuated;

a load beam coupled with said actuator arm; and

a HGA attached to said load beam, said HGA comprising:

a gimbal;

a head-slider coupled with said gimbal, comprising:

a slider;

a magnetic-recording head coupled with said slider, said magnetic-recording head comprising:

a write element configured to write data to said magnetic-recording disk; and

a read element configured to read data from said magnetic-recording disk.

14. The hard-disk drive of claim 13 wherein said piezoelectric element is coupled with said first vertical surface of said well using a viscoelastic adhesive.

15. The hard-disk drive of claim 13 wherein said piezoelectric element is not coupled with a top surface of said well and has freedom of motion relative to said top surface of said well.

16. The hard-disk drive of claim 13 wherein a neutral axis of said piezoelectric element is aligned with an estimated neutral axis of said actuator arm coupled with said piezoelectric element.

17. The hard-disk drive of claim 13 wherein a central axis of said piezoelectric element is aligned with said neutral axis of said actuator arm.

18. The hard-disk drive of claim 13 wherein said piezoelectric element comprises a first piezoelectric actuator and a second piezoelectric actuator.