公开(公告)号：JPH08339616A

公开(公告)日：1996-12-24

申请号：JP13304296

申请日：1996-05-28

Applicant: IBM

Inventor： ZAINETSUDEIIN BOUTAGOU ,  HARU BIYARUMARU OTSUTESEN ,  GOODON JIEEMUZU SUMISU

IPC: G11B19/04 ,  G06F11/00 ,  G11B5/09 ,  G11B5/54 ,  G11B20/18 ,  G11B21/02 ,  G11B21/12 ,  G11B21/22

Abstract: PROBLEM TO BE SOLVED: To presume that a catastrophic fault may occur shortly in the combination of a slider and a disk by analyzing reading errors which occur in the track band which is most influenced by loading/unloading operations. SOLUTION: A test pattern is read during a fixed number N of rotations and the number of soft errors per track(SFPT), namely, SFPT=SO/N is calculated. The SFPT is measured at every head (j) and called SEPT (j). The degree of deterioration is found from a normalized difference as understood from the formula. While a slider is in contact with a disk the potentials for the breakage of the disk and the performance deterioration of an air bearing can be decided by only measuring the SFR which is the half width of the slider, because both of an outside rail and an inside rail come into contact with the disk. Therefore, it can be presumed that a catastrophic fault may occur shortly in the combination of the slider and disk.

公开(公告)号：JPH07226015A

公开(公告)日：1995-08-22

申请号：JP30067694

申请日：1994-12-05

Applicant: IBM

Inventor： AOYANAGI AKIHIKO ,  ZAINETSUDEIIN BOUTAGOU ,  BUIJIYAIEESHIWARU DAASU KANNA ,  SUREESHIYU KUMAARU ,  MUTOUTANBI SHIYURII JIYAYANTA

IPC: G11B33/12 ,  F16C19/54 ,  F16C39/02 ,  G11B19/20 ,  G11B25/04

Abstract: PURPOSE: To prevent the crash of ball bearing at the device having a small from factor by providing a crash preventing ring inside of a rotator around a shaft and making the ring of a size allowing only a small amount of movement of the rotator with respect to the shaft. CONSTITUTION: In a spindle driving motor, a crash preventing ring 60 is inserted to the inside 64 of the rotator 18 to be engaged with it and to support it. The ring is formed so that a slight space or interval 66 may remain between the inner diameter 68 of the ring 60 and the shaft 12. Similarly a crash ring 62 is inserted to the inner cylindrical surface 64 of the rotator 18 to support. A small space 70 is left between the ring 62 and the shaft 12. At the time of trying to rotate the rotator 18 around a point P2 and another similar point along the shaft of the shaft 12, the rings 60 and 62 are shifted toward the outer periphery of the shaft 12 substantially in the direction of a radius and the space 66 and 70 are closed to be engaged with each other as the result. Then the movement of the rotator 18 in the direction of an arrow 32 is restricted to prevent the permanent plasticity deformation of bearing assemblies 16 and 17.