Magnetic disk device and actuator control method

Patent metadata

Field	Value
Publication number	US-10453486-B2
Application number	US-201816101662-A
Country	US
Kind code	B2
Filing date	Aug 13, 2018
Priority date	Mar 1, 2018
Publication date	Oct 22, 2019
Grant date	Oct 22, 2019

Abstract

According to one embodiment, a magnetic disk device includes a disk, a first head, a second head, an actuator configured to position the first head and the second head over the disk, and a controller configured to control the actuator based on a first value having a first waveform suppressing a disturbance component, wherein the controller is configured to invert, in the first waveform, a polarity of a third waveform succeeding a first timing with respect to a polarity of a second waveform preceding the first timing in a case where the first head is changed to the second head at the first timing.

First claim

What is claimed is:

1. A magnetic disk device comprising:
a disk comprising a first surface and a second surface opposite to the first surface;
a first head configured to execute read/write processing on the first surface;
a second head configured to execute read/write processing on the second surface;
an actuator configured to position the first head and the second head over the disk; and
a controller configured to control the actuator based on a first value suppressing a disturbance component,
wherein the controller is configured to adjust the first value based on at least one of a ratio between a first amplitude of the first head and a second amplitude of the second head and correction of phases in a case where the first head is changed to the second head at a first timing.

2. The magnetic disk device of claim 1 , wherein the controller comprises a filter configured to output the first value based on an input value and a memory in which a past input value input to the filter before input of the input value and a past output value output from the filter before output of the first value are recorded.

3. The magnetic disk device of claim 2 , wherein the controller is configured to multiply the past input value by the ratio to input a resultant value to the filter.

Assignees

• Toshiba Kk
• Toshiba Electronic Devices & Storage Corp

Inventors

• Sudo Daisuke

Classifications

• G11B5/59694

  System adaptation for working during or after external perturbation, e.g. in the presence of a mechanical oscillation caused by a shock · CPC title

• G11B5/59622

  Gain control; Filters · CPC title

• G11B5/5582 Primary

  system adaptation for working during or after external perturbation, e.g. in the presence of a mechanical oscillation caused by a shock · CPC title

• G11B5/5547 Primary

  "Seek" control and circuits therefor (G11B5/5556 takes precedence) · CPC title

• G11B5/5556

  with track following after a "seek" · CPC title