公开(公告)号：JPH11167779A

公开(公告)日：1999-06-22

申请号：JP32851797

申请日：1997-11-28

Applicant: IBM

Inventor： ARAI KOICHI ,  KOTANI YASUHIRO ,  KITAGAWA HIROSHI

IPC: G11B19/00 ,  G11B5/54 ,  G11B21/02 ,  G11B21/12 ,  H02P8/12 ,  H02P8/40

Abstract: PROBLEM TO BE SOLVED: To improve reliability of a disk device and to reduce a manufacturing cost. SOLUTION: A retracting circuit 13 receives a current by counter electromotive force from a spindle motor 2 and clips it to

公开(公告)号：JPH0547125A

公开(公告)日：1993-02-26

申请号：JP32832391

申请日：1991-11-18

Applicant: IBM

Inventor： ARAI KOICHI ,  HIEN FUU DAN ,  NAKAGAWA YUZO ,  HARU HIYARUMAA OTSUTESEN ,  ARUN SHIYARUMA ,  MUTOUTANBII SURIIJIYAYANTA

IPC: G11B21/10

Abstract: PURPOSE: To cope with variation in the resonance frequency of an actuator. CONSTITUTION: Under the control a microprocessor 33, a switch 50 is so set as to exclude a filter 48 and a sine wave of variable frequency from a sine wave generator 54 is supplied to a driving circuit 34 to drive an actuator including a suspension 28 and an arm 29 which support a head 14. The microprocessor 44 analyzes a position error signal obtained from a decoder 22 at this time to determine the resonance frequency of the actuator, and constitutes the filter 48 so that the determined resonance frequency is excluded. Then the switch 50 is so set as to supply a signal for driving to the driving circuit 34 through the filter 48.

公开(公告)号：JPH11191274A

公开(公告)日：1999-07-13

申请号：JP35780797

申请日：1997-12-25

Applicant: IBM

Inventor： ASANO HIDEO ,  OKADA KENJI ,  UEDA TETSUO ,  ARAI KOICHI ,  OZEKI HIDENORI

IPC: G11B21/10 ,  G11B5/55

Abstract: PROBLEM TO BE SOLVED: To provide a disk drive device, a seek controller easy to make a narrow track pitch. SOLUTION: The data are recorded by adding an offset to a position of a reproducing head 22 according to the reproducing head 22 according to a yaw θ of a head and the offset ΔW in the track width direction of a recording head. At a reproducing time, the position of the reproducing head 22 is made the position of the recording head 23 at a recording time, the middle position between the position of the recording head 23 at a recording time and the position of the reproducing head 22 at the recording time or a center of a track, and the reproducing is performed.

公开(公告)号：JPH09167303A

公开(公告)日：1997-06-24

申请号：JP33030095

申请日：1995-12-19

Applicant: IBM

Inventor： OKADA KENJI ,  ARAI KOICHI ,  TSUNODA HISASHI ,  SUZUKI HIROMASA ,  SASAKI MASAKAZU ,  KIHASHI AKIRA ,  ENDO TATSUYA

IPC: G11B21/02 ,  G11B5/00 ,  G11B5/012 ,  G11B5/02 ,  G11B20/18 ,  G11B20/24 ,  G11B27/36 ,  G11B33/10

Abstract: PROBLEM TO BE SOLVED: To eliminate generation of thermal asperity and to avoid generation of error by making head vibration have a directional component approaching the disk surface. SOLUTION: When an error is generated, a vibration signal from a means 52 is superposed on a signal from a controller 43 by a direction of HDC and supplied to a VCM driving means 45. And a head 20 is positioned at a desired position according to thermal asperity position. By providing the VCM 46 with a vibration signal, a head assembly starts rolling movement centering the joint point with a dimple. And the head assembly generates vertical vibration with a frequency equivalent to the given vibration signal frequency, and eliminate the thermal asperity on the disk.

公开(公告)号：JPH0689516A

公开(公告)日：1994-03-29

申请号：JP24529092

申请日：1992-09-14

Applicant: IBM

Inventor： ARAI KOICHI ,  HARU HIYARUMAA OTSUTESEN ,  ARAN SHIYARUMA ,  MACHIYUSANBII SURIIJIYAYANSA ,  MAIKERU CHIYAARUZU SUTEITSUKU

IPC: G11B21/08 ,  G11B5/596 ,  G11B19/02

Abstract: PURPOSE: To reduce seek time and to prevent overshooting by executing interpolation for deciding optimum time during the reception of a position error signal switching the current of a voice coil motor. CONSTITUTION: Reference track information R(K) and demodulation error signal information X(K) from a bus 46 are inputted to a subtraction node 150 and a difference signal E(K) is generated in a lead 151. The difference signal is supplied to an integrator 154 and a controller 156 and is supplied to an estimator 158 generating an estimation signal output. Estimation speed at the time of sampling (k), which is generated at the estimator, is supplied to the controller 156 through a lead 159. The extrapolation value of speed on a lead 160 is calculated in accordance with sampling k+1, and an extrapolation position V is also calculated to the lead 161 of a head. Then, it is supplied to the controller 156.