Disk drive having a two-stage actuator for suppressing a flying-height fluctuation
View Patent ↗There is provided a magnetic disk drive in which a flying-height fluctuation produced by the operation of a fine actuator is decreased, the reliability is high, and recording density is high. For this purpose, the magnetic disk drive is configured as described below. The magnetic disk drive has a suspension including a base plate connected to a carriage, a load beam fitted with a slider, and a fine actuator which is provided on the base plate and finely moves the load beam. The configuration is such that the shortest track travel time using the fine actuator is larger than the inverse number of the local maximum of a flying-height fluctuation frequency of the suspension by the fine actuator. Also, the configuration is such that the shortest track travel time using the fine actuator is larger than the inverse number of the natural frequency of first torsion mode of the suspension by the fine actuator.
1. A disk drive comprising:
a disk for recording information;
a suspension provided with a slider having a head for reading information recorded on said disk; and
a fine actuator for finely moving said head of said slider,
wherein the shortest track travel time using said fine actuator is larger than twice the inverse number of a local maximum of a flying-height fluctuation frequency of said suspension by said fine actuator, and the flying-height fluctuation of the suspension being within 5% during said shortest track travel time.
2. A disk drive comprising:
a disk for recording information;
a suspension provided with a slider having a head for reading information recorded on said disk; and
a fine actuator for finely moving said head of said slider,
wherein the shortest track travel time using said fine actuator is larger than twice the inverse number of a natural frequency of a first torsion mode of said suspension by said fine actuator, and the flying-height fluctuation of the suspension being within 5% during said shortest track travel time.
3. A disk drive according to claim 1 , wherein said fine actuator is comprised of a piezoelectric element.
4. A disk drive according to claim 2 , wherein said fine actuator is comprised of a piezoelectric element.