Disk drive suspension assembly with rotary fine actuator at flexure tongue
View Patent ↗A head gimbal assembly includes a rotary fine actuator attached to the head mounting tongue. The rotary fine actuator includes a fixed portion, a head mounting platform, first and second piezoelectric elements, and first and second curved compliant members. The first piezoelectric element is bonded to the fixed portion at a first bonding surface, and to the head mounting platform at a second bonding surface. The second piezoelectric element extends between the fixed portion and the head mounting platform. The first and second curved compliant members extend between the fixed portion and the head mounting platform. A read head is bonded to a mounting surface of the head mounting platform. The first and second bonding surfaces are parallel to the mounting surface. The read head is disposed between the first and second piezoelectric elements.
1. A head gimbal assembly (HGA) comprising:
a suspension assembly, the suspension assembly including
a suspension assembly mounting plate;
a load beam extending from the suspension assembly mounting plate and defining a load beam longitudinal axis;
a laminated flexure attached to the load beam, the laminated flexure including a head mounting tongue, and a rotary fine actuator attached to the head mounting tongue, the rotary fine actuator comprising
a fixed portion having a first bonding surface,
a head mounting platform having a second bonding surface,
a first piezoelectric element defining a first element longitudinal axis that is parallel to the load beam longitudinal axis, the first piezoelectric element being bonded to the first and second bonding surfaces;
a second piezoelectric element extending between the fixed portion and the head mounting platform;
first and second curved compliant members extending between the fixed portion and the head mounting platform; and
a read head bonded to a mounting surface of the head mounting platform, the first and second bonding surfaces being parallel to the mounting surface, the read head being disposed between the first and second piezoelectric elements.
2. The HGA of claim 1 wherein the load beam includes a dimple in contact with the head mounting tongue at a dimple contact location.
3. The HGA of claim 2 wherein the rotary fine actuator defines an axis of rotation that passes through the dimple contact location.
4. The HGA of claim 1 wherein the head mounting tongue, the fixed portion, the head mounting platform, and the first and second curved compliant members are a single component having material continuity rather than being an assembly of sub-components.
5. The HGA of claim 4 wherein the head mounting tongue, the fixed portion, the head mounting platform, and the first and second curved compliant members are distinct regions of a single stainless steel sheet, each distinct region being at least partially bounded and defined by etched openings through the single stainless steel sheet.
6. The HGA of claim 1 wherein the mounting surface defines a mounting plane, and wherein the first and second piezoelectric elements are disposed on the same side of the mounting plane as is the read head.
7. The HGA of claim 1 wherein the laminated flexure includes a structural layer, a dielectric layer, and a conductive layer that defines a plurality of conductive traces, and wherein the read head is electrically connected to more than one of the plurality of conductive traces, and the first and second piezoelectric elements are each electrically connected to at least one of the plurality of conductive traces.
8. The HGA of claim 1 wherein the first and second piezoelectric elements are disposed closer to the read head than are the first and second curved compliant members.
9. The HGA of claim 1 further comprising third and fourth piezoelectric elements extending between the fixed portion and the head mounting platform.
10. The HGA of claim 1 further comprising third and fourth curved compliant members extending between the fixed portion and the head mounting platform.
11. The disk drive of claim 1 wherein the first and second piezoelectric elements are disposed closer to the read head than are the first and second curved compliant members.
12. A disk drive comprising:
a disk drive base;
a spindle attached to the disk drive base;
a disk mounted on the spindle;
a coarse actuator pivotally attached to the disk drive base and defining a coarse actuator pivot axis, the coarse actuator including an actuator arm that defines an arm longitudinal axis that is normal to the coarse actuator pivot axis;
a suspension assembly, the suspension assembly including
a suspension assembly mounting plate attached to the actuator arm;
a load beam extending from the suspension assembly mounting plate;
a laminated flexure attached to the load beam, the laminated flexure including a head mounting tongue, and a rotary fine actuator attached to the head mounting tongue, the rotary fine actuator comprising
a fixed portion having a first bonding surface,
a head mounting platform having a second bonding surface,
a first piezoelectric element defining a first element longitudinal axis that is parallel to the load beam longitudinal axis, the first piezoelectric element being bonded to the first and second bonding surfaces;
a second piezoelectric element extending between the fixed portion and the head mounting platform;
first and second curved compliant members extending between the fixed portion and the head mounting platform; and
a read head bonded to a mounting surface of the head mounting platform, the first and second bonding surfaces being parallel to the mounting surface, and the read head being disposed between the first and second piezoelectric elements.
13. The disk drive of claim 12 wherein the load beam includes a dimple in contact with the head mounting tongue at a dimple contact location.
14. The disk drive of claim 13 wherein the rotary fine actuator defines an axis of rotation that passes through the dimple contact location.
15. The disk drive of claim 12 wherein the head mounting tongue, the fixed portion, the head mounting platform, and the first and second curved compliant members are a single component having material continuity rather than being an assembly of sub-components.
16. The disk drive of claim 15 wherein the head mounting tongue, the fixed portion, the head mounting platform, and the first and second curved compliant members are distinct regions of a single stainless steel sheet, each distinct region being at least partially bounded and defined by etched openings through the single stainless steel sheet.
17. The disk drive of claim 12 wherein the mounting surface defines a mounting plane, and wherein the first and second piezoelectric elements are disposed on the same side of the mounting plane as is the read head.
18. The disk drive of claim 12 wherein the laminated flexure includes a structural layer, a dielectric layer, and a conductive layer that defines a plurality of conductive traces, and wherein the read head is electrically connected to more than one of the plurality of conductive traces, and the first and second piezoelectric elements are each electrically connected to at least one of the plurality of conductive traces.
19. The disk drive of claim 18 further comprising third and fourth piezoelectric elements extending between the fixed portion and the head mounting platform.
20. The disk drive of claim 18 further comprising third and fourth curved compliant members extending between the fixed portion and the head mounting platform.