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Patent JPS60147979A successfully refreshed from Google Patents.
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JPS60147979A Expired / Lapsed JP ⏱️ 0.0 years remaining

Magnetic disk device

Assignee: Fujitsu Ltd
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Filing: 1984-01-12
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Granted: —
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Expires: 2004-01-12
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Abstract

Abstract PURPOSE:To maximize attraction releasing force and rotation motive power at the time of starting rotation and to suppress current capacity of a DC motor by rising gradually starting current of a DC motor for driving spindle, and releasing attraction of a head by a differential current between the current and saturation current. CONSTITUTION:A DC motor driving section 5 is controlled to rise up slowly through a starting current restricting circuit section 6 according to recording/reproducing operation, and a motor 1 for driving spindle of a disk device is rotated. At the same time, the differential current between a driving current and the saturation current of the motor 1 of reference current is supplied to a voice coil 8 for attraction releasing of a magnetic head actuator from an operational amplifier 7 through a switch SW11 etc. that responds to a signal COMP. When the speed of the motor 1, attains to the specified value it is detected by a Hall element 2, the signal COMP disapears and power supplying to the coil 8 is stopped. In such constitution, attraction releasing force and rotation starting force of the disk when starting rotation of the magnetic disk can be maximized and current capacity of the DC motor can be suppressed.

Inventors

  • 👤 Takahisa Mihara
  • 👤 隆久 三原

Bibliographic Details

Application Number —
Jurisdiction JP
Data Source google_patents
Last Synchronized 2026-11-09 08:38
CPC Classifications
G; G11; G11B; G11B19/00; G11B19/20; G11B5/00; G11B5/48; G11B5/54

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