Disk drive rotary actuator assembly having a constrained layer damper attached to a flat actuator coil
View Patent ↗A head stack assembly for a disk drive includes a rotary actuator assembly. The rotary actuator assembly includes an actuator body having a bore defining a pivot axis, an actuator arm cantilevered from the actuator body, and a coil portion cantilevered from the actuator body in a direction opposite from the actuator arm. The coil portion includes a coil support, a flat coil supported by the coil support, the flat coil including a coil surface generally perpendicular to the pivot axis, and a constrained layer damper attached to the coil surface. The constrained layer damper includes a stiffening layer having a coil-facing planar surface generally perpendicular to the pivot axis and an adhesive layer positioned between the coil-facing planar surface and the coil surface.
1. A rotary actuator assembly for a disk drive comprising:
an actuator body having a bore defining a pivot axis;
an actuator arm cantilevered from the actuator body;
a coil portion cantilevered from the actuator body in a direction opposite from the actuator arm;
the coil portion including:
a coil support;
a flat coil supported by the coil support, the flat coil including a coil surface generally perpendicular to the pivot axis;
a constrained layer damper attached to the coil surface and the coil support;
the constrained layer damper including:
a stiffening layer having a coil-facing planar surface generally perpendicular to the pivot axis; and
an adhesive layer positioned between the coil facing planar surface and the coil surface, the adhesive layer abutting the coil surface and the coil support;
wherein the constrained layer damper includes an aperture.
2. The rotary actuator assembly of claim 1 , wherein the adhesive layer is a viscoelastic adhesive layer.
3. The rotary actuator assembly of claim 1 , wherein the coil support includes a pair of actuator fork members for supporting the flat coil and the constrained layer damper overlaps the actuator fork members.
4. A head stack assembly for a disk drive comprising:
a rotary actuator assembly including:
an actuator body having a bore defining a pivot axis;
an actuator arm cantilevered from the actuator body;
a coil portion cantilevered from the actuator body in a direction opposite from the actuator arm;
the coil portion including:
a coil support;
a flat coil supported by the coil support, the flat coil including a coil surface generally perpendicular to the pivot axis;
a constrained layer damper attached to the coil surface and the coil support;
the constrained layer damper including:
a stiffening layer having a coil-facing planar surface generally perpendicular to the pivot axis; and
an adhesive layer positioned between the coil-facing planar surface and the coil surface, the adhesive layer abutting to the coil surface and the coil support;
wherein the constrained layer damper includes an aperture.
5. The head stack assembly of claim 4 , wherein the adhesive layer is a viscoelastic adhesive layer.
6. The head stack assembly of claim 4 , wherein the coil support includes a pair of actuator fork members for supporting the flat coil and the constrained layer damper overlaps the actuator fork members.
7. A disk drive comprising:
a base;
a spindle motor attached to the base;
a disk supported by the spindle motor; and
a head stack assembly supported by the base;
the head stack assembly including:
a rotary actuator assembly including:
an actuator body having a bore defining a pivot axis;
an actuator arm cantilevered from the actuator body;
a coil portion cantilevered from the actuator body in a direction opposite from the actuator arm;
the coil portion including:
a coil support;
a flat coil supported by the coil support, the flat coil including a coil surface generally perpendicular to the pivot axis;
a constrained layer damper attached to the coil surface and the coil support;
the constrained layer damper including:
a stiffening layer having a coil-facing planar surface generally perpendicular to the pivot axis; and
an adhesive layer positioned between the coil-facing planar surface and the coil surface, the adhesive layer abutting the coil surface and the coil support;
wherein the constrained layer damper includes an aperture.
8. The disk drive of claim 7 , wherein the adhesive layer is a viscoelastic adhesive layer.
9. The disk drive of claim 7 , wherein the coil support includes a pair of actuator fork members for supporting the flat coil and the constrained layer damper overlaps the actuator fork members.