In-situ dynamic pitch and roll adjustment in hard disk drives
View Patent ↗Disclosed is a head gimbal assembly for a hard disk drive that includes a head pivotally connected to a flexure. The flexure has a longitudinal axis. The assembly includes first and second micro-actuators that are located between the flexure and the head and spaced from the longitudinal axis. By way of example, the first and second micro-actuators may be thin piezo-electric transducers. Control signals can be provided to the micro-actuators to vary the pitch and/or roll of the head.
1. A head gimbal assembly for a hard disk drive, comprising:
a flexure that has a longitudinal axis;
a head pivotally connected to said flexure;
a first micro-actuator that is located between said flexure and said head and spaced a first distance from said longitudinal axis; and,
a second micro-actuator that is located between said flexure and said head and spaced a second distance from said longitudinal axis.
2. The assembly of claim 1 , wherein said first and second micro-actuators are each piezo-electric transducers.
3. The assembly of claim 1 , wherein said first and second micro-actuators are attached to said flexure.
4. The assembly of claim 1 , wherein said first distance is equal to said second distance.
5. A hard disk drive, comprising:
a disk;
a spindle motor that rotates said disk;
a head gimbal assembly that is coupled to said disk, said head gimbal assembly including;
a flexure that has a longitudinal axis;
a head pivotally connected to said flexure;
a first micro-actuator that is located between said flexure and said head and spaced a first distance from said longitudinal axis;
a second micro-actuator that is located between said flexure and said head and spaced a second distance from said longitudinal axis; and,
a controller that is coupled to said head and provides control signals to said first and second micro-actuators to control a roll and a pitch of said head.
6. The disk drive of claim 5 , wherein said first and second micro-actuators are each piezo-electric transducers.
7. The disk drive of claim 5 , wherein said first and second micro-actuators are attached to said flexure.
8. The disk drive of claim 5 , wherein said first distance is equal to said second distance.
9. The disk drive of claim 5 , wherein said controller provides a first control signal to said first micro-actuator that is different than a second control signal provided to said second micro-actuator.
10. A method for controlling a flying characteristic of a head in a hard disk drive, comprising:
sending a first control signal to a first micro-actuator located between a flexure and a head; and,
sending a second control signal to a second micro-actuator located between the flexure and the head.
11. The method of claim 10 , wherein the first control signal is different from the second control signal.
12. The method of claim 10 , wherein the first and second micro-actuators together move the head to vary a head pitch.
13. The method of claim 10 , wherein either the first or the second micro-actuator move the head to vary a head roll.