公开(公告)号：JPH10269728A

公开(公告)日：1998-10-09

申请号：JP7551597

申请日：1997-03-27

Applicant: IBM

Inventor： UEDA TETSUO ,  SATO KIYOSHI ,  ONO HIROYUKI ,  WADA TOSHIAKI

IPC: G11B5/55 ,  G11B19/02 ,  G11B19/04 ,  G11B21/08 ,  G11B21/10

Abstract: PROBLEM TO BE SOLVED: To raise the allowable value of the track width direction velocity of a head immediately after the end of seek operation in which the head position is unstable in order to prevent the off-track recording by inhibiting the write operation of head when the track width direction velocity of head exceeds the allowable value. SOLUTION: With the data writing instruction, a hard disk controller HDC 10 controls a micro-processor unit MPU 6 to move a magnetic head 2 to the target track. HDC 10 causes the magnetic head 2 to move on the target track through the track following control with a position error RES signal supplied from a servo sector reproducing unit 8a to start the write operation. In the writing operation at the off-track position, since the adjacent track data may probably be broken, the allowable position error of the magnetic head 2 is set and when PES from the target track exceeds the allowable position error, the write operation is inhibited. Moreover, when the track width direction velocity of magnetic head is higher than the allowable value, since PES may probably exceed the position error, the write operation is inhibited.

公开(公告)号：JPH10162494A

公开(公告)日：1998-06-19

申请号：JP32267196

申请日：1996-12-03

Applicant: IBM

Inventor： ONO HIROYUKI ,  UEDA TETSUO ,  OKUTSU KAZUE

IPC: G11B5/012 ,  G11B19/04 ,  G11B19/28 ,  G11B20/18 ,  G11B23/50 ,  G11B25/04 ,  G11B33/14

Abstract: PROBLEM TO BE SOLVED: To increase the possibility to correct the reading error of data in a disk device and to effectively recover the error against the reading error due to the thermal asperity by making a head execute the reading operation in the manner of reducing the number of rotation of a motor to be lower than the prescribed number of rotation. SOLUTION: This disk device 100 consists of a controller pad 110 and a disk part 130, and the disk part 130 is provided with the motor 134 integrally rotating the disks 136A, 136B through a spindle 132. By this error recovering method, the number of rotation of the motor 134 is lowered than the prescribed number of rotation, and a reading frequency of the head is lowered to the frequency corresponding to this number of rotation to make the head execute the reading operation. Thus, the length of error bit of the read-out data influenced by the asperity is shortened, and the possibility of recovery by the ECC which is an error recovery code is increased.

公开(公告)号：JPH02156467A

公开(公告)日：1990-06-15

申请号：JP30989088

申请日：1988-12-09

Applicant: IBM JAPAN

Inventor： FUKUNAGA SEIJI ,  NAKAMURA TAKASHI ,  ONO HIROYUKI

IPC: G01P3/44 ,  G01P3/489 ,  G11B19/247 ,  G11B19/28

Abstract: PURPOSE:To obtain a pulse following the rotational characteristic of a motor by eliminating the error components of a sensor and a pattern by mounting a light pattern on the shaft of the motor to rotate a magnetic disk, detecting it by an optical sensor, and inputting the output of the sensor to a sector boundary reference generator and a light pattern error generator. CONSTITUTION:A light pattern label 8 on which a black pattern 8a and a white pattern 8b are printed alternately in a radius direction is stuck on the rotor 6 of a spindle motor 4 which drives the magnetic disk 2. The label 8 is irradiated with light from a light source 10, and reflected light from the label is inputted to the optical sensor 12, and the pulse following the rotational characteristic of the motor 4 is outputted from the sensor. Here, the number of patterns 8a and 8b in a circumferential direction is decided at the number sufficiently following the wow component and the flatter component of the motor 4. Afterwards, the output of the sensor 12 is inputted to the sector boundary reference generator 14 and the light pattern error generator 16, and results are sent to first and second counting logic circuits 18 and 22, and a sector boundary signal 24 is sent from the circuit 22.

公开(公告)号：JPH06138906A

公开(公告)日：1994-05-20

申请号：JP26763292

申请日：1992-10-06

Applicant: IBM

Inventor： ISOGI KOUICHI ,  ONO HIROYUKI

IPC: G05B13/02 ,  G05B11/42 ,  G05B13/04 ,  G05B17/02 ,  G05D3/12

Abstract: PURPOSE: To prevent the number of bits required for calculation (a dynamic range) from being affected by the level of a target value. CONSTITUTION: The state parameter of a controlled system 30 is inputted to an inverse system 34 having characteristics inverse to an internal model 32, and the output of the inverse system 34 is inputted to the internal model 32. When the state parameter of the controlled system 30 can not be directly observed, a state estimator 40 is used. In such a case, the inverse system 34 receives the input / output of the controlled system 30 and supplies that output to the state estimator 40. In place of inputting the input of the controlled system 30 to the inverse system 34, the input of the internal model 32 can be inputted to the state estimator 40 as well.

公开(公告)号：JP2001005616A

公开(公告)日：2001-01-12

申请号：JP16462599

申请日：1999-06-11

Applicant: IBM

Inventor： ONO HIROYUKI ,  ASANO HIDEO ,  KANAMARU ATSUSHI

IPC: G06F12/16 ,  G06F3/06 ,  G06F11/22 ,  G11B5/09 ,  G11B20/10 ,  G11B20/18 ,  G11C29/00

Abstract: PROBLEM TO BE SOLVED: To eliminate a momentary decrease in performance as much as possible by performing a specific inspection regarding a function in a standby state wherein there is no access from a host. SOLUTION: It is judged whether the disk storage device is in standby mode (S1) and when not, commands from the host which are generated in a specific time are executed (S2) in current execution or after the execution temporarily ends. When it is judged that the device is in standby mode, a read test by a sequential read and a write servo test conducted by positioning a head at a write position are carried out so as to search for a bad sector and a write test by data writing to a specific sector is carried out to judge abnormality of the head. Consequently, when a bad sector is found through the read test or write servo test, it is formed in a preliminary area on a disk and reassigned to an alternative sector and when an abnormality of the head is found through the write test, that is reported to a user (S3).

公开(公告)号：JPH05342790A

公开(公告)日：1993-12-24

申请号：JP15043392

申请日：1992-06-10

Applicant: SONY TEKTRONIX CORP ,  IBM

Inventor： URUSHIBARA TOMIO ,  TAKASUGI HISASHI ,  ONO HIROYUKI

IPC: G11B21/12 ,  G11B21/21

Abstract: PURPOSE: To enable optionally loading and unloading a magnetic head by making a magnetic head loading device to be a simple structure and a small size. CONSTITUTION: A turning block 201 turns around a pole shaft 221, extending from a main body block 100. The turning block 201 is provided with a wire 241 extending from its one end to a head arm 141 and adding force opposing to the elastic force of the head arm 141, when the turning block 201 is turned. A rotary shaft 280 extendends from the main body block 100. A leaf spring 300 is fixed to the other end of the turning block 201 in its one end. When the rotary shaft 280 is left rotated, the leaf spring 300 is rolled in the rotary shaft 280, and the turning block 201 is turned.