公开(公告)号：JPH07320248A

公开(公告)日：1995-12-08

申请号：JP10878194

申请日：1994-05-23

Applicant: IBM

Inventor： KUROKI KENJI ,  MATSUI TAKAO

IPC: G11B5/39 ,  G11B5/00 ,  G11B5/012 ,  G11B5/02 ,  G11B5/55 ,  G11B5/596

Abstract: PURPOSE: To reduce the non-detection and erroneous detection of information. CONSTITUTION: A controller body 40 for an HDC 30 is connected to a driving device 28, and an arm is turned at a fixed angle. A magnetic head 20A functioning as an MR head placed at the front end of the arm and consisting of a recording element and a reproducing element is supplied with a bias current through a driver 36A and a switch circuit 32A from the main body 40, and the magnetic field of a disk 18A is detected by a detector 38A through the switch circuit 32A. The switch circuit 32A inverts the polarity of a current fed to the magnetic head 20A by a signal from the controller body 40 corresponding to a skew angle. Accordingly, the direction of a bias magnetic field is changed, the effective sensibility place of the reproducing element is brought near to the recording element, and an offtrack can be reduced.

公开(公告)号：JPH05307879A

公开(公告)日：1993-11-19

申请号：JP11157992

申请日：1992-04-30

Applicant: IBM

Inventor： KUROKI KENJI ,  HARADA YOSHINAO ,  OTA SHUNICHIRO

IPC: G11B23/00 ,  G11B25/04 ,  G11B33/14 ,  G11B23/03

Abstract: PURPOSE: To execute a restriction and a mitigation, despite the change in relative temp. and relative humidity inside a hard disk drive by providing a wide surface area, in order to permit moisture absorption on the inner surface of a disk enclusure. CONSTITUTION: An anodically oxidized porous coat having porous surface structure is generated on the surface of an aluminum plate to be used in the disk enclosure, by the anodic oxidization method using oxalic acid. The hard disk drive is assembled by incorporating elements, such as a disk driving device 11 having a disk 11a and a head driving part 12, etc., having a head 12a inside the disk enclosure 10. Air volume inside the hard disk drive is 80ml, and the whole inner surface area of the enclosure 10 is about 3.2m . Thus, relative humidity inside the drive is lowered, when temp. is increased and absorption moisture on the inner surface of the enclusure 10 is vaporized. Conversely, vapor is absorbed on the surface inside the enclosure 10 when relative humidity is increased at the time of temp. lowering and temp. change is restricted.

公开(公告)号：JP2001312802A

公开(公告)日：2001-11-09

申请号：JP2000126708

申请日：2000-04-26

Applicant: IBM

Inventor： OTA MUTSURO ,  KUROKI KENJI ,  MATSUDA HIROSHI ,  TAKAHASHI HIROSHI ,  NOGUCHI SATOSHI ,  KITABORI HIRONORI ,  TAMURA HITOSHI

IPC: G11B5/024 ,  H01F7/14

Abstract: PROBLEM TO BE SOLVED: To provide a disk device which can effectively erase data on a magnetic disk while suppressing the operation of a magnetic field on a spindle motor. SOLUTION: The top cover 14 of the disk device is provided with pole pieces 14a1 and 14a2. When this disk device is placed in an external magnetic field, a magnetic field which is local and has a steeper magnetic gradient than the external magnetic field is produced from the pole pieces 14a1 and 14a2. When the pole pieces 14a1 and 14a2 are arranged on the inner peripheral side of the magnetic disk, data on the magnetic disk can effectively be erased while the operation of the magnetic field on the spindle motor is suppressed.

公开(公告)号：JP2000243044A

公开(公告)日：2000-09-08

申请号：JP3426199

申请日：1999-02-12

Applicant: IBM

Inventor： MATSUMURA SATOSHI ,  KUROKI KENJI ,  ALBRECHT THOMAS R ,  DAVID W ALBRECHT

IPC: G11B21/16 ,  G11B5/48 ,  G11B5/60 ,  G11B21/02

Abstract: PROBLEM TO BE SOLVED: To miniaturize a device by forming reference point members for positioning a first head gimbals assembly on a first surface and positioning a second head gimbals assembly on a second surface respectively on the first surface and second surface. SOLUTION: The upper head gimbals assembly(HGA) 49A includes an arm member 51A, a suspension load beam 53A and an integral type wiring plate 54A. A center line CL1 is extended along the longitudinal direction of a head stack assembly and an opening 55 aligned with its center is formed at a carriage 48. The first reference pins 57A and 58A and the opening 55 are formed on the carriage 48 in such a manner that the opening 55 through which a pivot cartridge 42 passes is arranged between the first reference pin 57A and the second reference pin 58A. The line 60 passing the first and second first reference pins 57A and 58A is inclined by an angle α1 from the center line CL1 of the head stack assembly.

公开(公告)号：JPH0845036A

公开(公告)日：1996-02-16

申请号：JP7102995

申请日：1995-03-29

Applicant: IBM

Inventor： GUREN ADAMU GAAFUANKURU ,  MAIKU POURU SARO ,  AOYANAGI AKIHIKO ,  YANAGISAWA HIROSHI ,  TERAJIMA HIROSHI ,  KUROKI KENJI

IPC: G11B5/00 ,  G11B5/39 ,  G11B5/465 ,  G11B5/48 ,  G11B19/02

Abstract: PURPOSE: To improve productivity by simultaneously initializing MR elements by a strong uniform magnetic field at a time point when an actuator head stack is constituted. CONSTITUTION: An MR sensor is formed on a vertical surface 31 of a slider 13 by an MR element 32 made of a ferromagnetic material and a lateral bias layer 38 made of a soft magnetic material, and has its air bearing surface ABS brought in close contact with a magnetic recording surface of a recording medium. In order to read magnetic recording on both sides of the recording medium, an actuator head stack is constituted by a pair of upper and lower MR sensors with air bearing surfaces ABS thereof facing each other. At this point, an initialized magnetic field H1 N1 T is applied by a strong uniform magnetic field of an electromagnet or the like, thereby simultaneously initializing the MR elements 32. That is, the upper and lower MR sensors have opposite directions of initialized magnetic field H1 N1 T. Thus, a wiring is so set that a sensor current I is in opposite directions in the upper and lower MR sensors, thereby obtaining an output of correct polarity.