公开(公告)号：EP0262690A3

公开(公告)日：1988-09-28

申请号：EP87114637

申请日：1983-05-06

Applicant: DIGITAL EQUIPMENT CORPORATION

Inventor： Sidman, Michael D.

IPC: G11B05/55 ,  G11B05/596

CPC classification number: G11B5/5965 ,  G11B5/5534

Abstract: A method for use in a magnetic disk drive of the type in which a disk assembly has a dedicated servo surface containing circular tracks of dedicated servo signals (75) and data surfaces containing circular data tracks divided into sectors each of which includes a data field (256) and a servo field (254) containing embedded servo signals, a dedicated servo signal detector for detecting servo signals (75) on said dedicated surface, an embedded signal detector for detecting embedded servo signals (254) on a data surface and a head positioning system for positioning a read/write head over a selec­ted data track. The entire output of the embedded signal detector is combined with the high-frequency components of the output of the dedicated signal detec­tor to produce a composite track error signal and the head positioning system responds to the composite track error signal to maintain the read/write head over the selected data track.

公开(公告)号：EP0162349A3

公开(公告)日：1988-09-07

申请号：EP85105240

申请日：1985-04-30

Applicant: International Business Machines Corporation

Inventor： Best, John Steward ,  Romankiw, Lubomyr Taras ,  Scranton, Robert Alan ,  Thompson, David Allen

IPC: G11B05/596 ,  G11B21/10 ,  G11B05/74 ,  G11B05/82 ,  G11B09/02 ,  G11B09/04 ,  G11B09/06 ,  G11B23/00 ,  G11B07/24

CPC classification number: G11B7/0938 ,  G11B5/58 ,  G11B5/596 ,  G11B5/74 ,  G11B5/82 ,  G11B7/24 ,  G11B23/30

Abstract: A data recording medium including a structure providing variable electromagnetic property (variable, resistance, capacitive, or other variable impedance or other variable electromagnetic property) contrast on the surface marking servo tracks. Such media include magnetic or optical storage disks and tapes. The media can be conductive metallic or nonmetallic and can be composed for example of poorly conductive media, dielectric media, or semiconductive media. The variable electromagnetic impedance can vary in the optical, electrical or other portions of the electromagnetic spectrum. A very small variation of the thickness of the protective layer above the magnetic recording medium is employed to mark the servo track information of the medium. Information to be detected by means of a capacitive sensor can be recorded in the protective layer above or below the magnetic recording or optical storage medium. For example, a thin film metallic protective layer 0.07 micrometers thick can be patterned with about 0.02 micrometers of the protective layer. For a plated disk, the top 0.02 micrometers of the protective layer can be patterned. A pattern for providing a variable impedance for representing data can be formed subtractively by sputter etching, or additively formed by a lift-off process or by deposition through a mask, or by the oxidation of or nitriding of materials such as Al, Si or valve metals.

公开(公告)号：EP0138202A3

公开(公告)日：1987-03-25

申请号：EP84112239

申请日：1984-10-11

Applicant: FUJI PHOTO FILM CO., LTD.

Inventor： Itoh, Haruo c/o Fuji Photo Film Co., Ltd.

IPC: G11B05/596 ,  G11B21/10

CPC classification number: G11B5/59611 ,  G11B27/34

Abstract: A tracking system for a rotary magnetic recording medium (10) includes a magnetic head (26) for sensing signals on a plurality of tracks formed on the recording medium such that a beginning and an end of recording align with each other, a head feeding unit (28, 30, 50) for transporting the magnetic head to a position where desired one of the tracks is located, and a control unit (100) for controlling the head feeding unit to effect tracking. The control unit (100) includes an operational unit (46, 104, 106, 108, 110) for sampling a signal sensed by the head in response to a rotation of the recording medium at a plurality of sampling points, and adds the sampled values with predetermined weights. Based on a result of the weighted addition, the control unit (100) performs a tracking control.

公开(公告)号：WO1997028529A1

公开(公告)日：1997-08-07

申请号：PCT/US1997001345

申请日：1997-01-28

Applicant: SEAGATE TECHNOLOGY, INC.

Inventor： SEAGATE TECHNOLOGY, INC. ,  VOLZ, LeRoy, A. ,  MANZ, Stephen, R. ,  HURST, Raymond, E.

IPC: G11B05/596

CPC classification number: G11B5/59655

Abstract: A method and apparatus determining a data transducer head (26) position relative to a selected track (18) of plural concentric tracks within a magnetic disk drive (10). At least one prerecorded servo sector (20) within a data track includes four time staggered servo bursts (50). The first pair (70, 72) and second pair (74, 76) of servo bursts are radially offset from each other by generally a burst width such that an edge from each of the pair is substantially co-linear in forming a track null. The first pair (70, 72) is radially offset from the second pair (74, 76) by one-half of the burst width. The first pair (70, 72) is read to determine a first relative amplitude (100), and the second pair (74, 76) is read to determine a second relative amplitude (102). The radially offset, time staggered prerecorded servo bursts (50) can be of varying width and number to create the plurality of track nulls within a data track (18) about which the head (26) is positioned.

Abstract translation: 一种确定数据换能器头（26）相对于磁盘驱动器（10）内的多个同心轨道的选定轨道（18）的位置的方法和装置。 数据轨道内的至少一个预先记录的伺服扇区（20）包括四个交错的伺服脉冲串（50）。 伺服脉冲串的第一对（70,72）和第二对（74,76）通过一般的突发宽度彼此径向偏移，使得来自该对中每一个的边缘在形成磁道零点时基本上是共线的。 第一对（70,72）从第二对（74,76）径向偏移了突发宽度的一半。 读取第一对（70,72）以确定第一相对幅度（100），并且读取第二对（74,76）以确定第二相对幅度（102）。 径向偏移的时间交错的预先记录的伺服脉冲串（50）可以具有变化的宽度和数量，以在磁头（26）围绕其定位的数据磁道（18）内创建多个磁道零点。

公开(公告)号：WO1997022966A1

公开(公告)日：1997-06-26

申请号：PCT/US1996020438

申请日：1996-12-17

Applicant: SEAGATE TECHNOLOGY, INC.

Inventor： SEAGATE TECHNOLOGY, INC. ,  TENG, Jack, M. ,  LOH, Peng, Y.

IPC: G11B05/596

CPC classification number: G11B5/59655 ,  G11B27/36

Abstract: A method to determine defective servo bursts written on a recording medium. Position data portions (10) include servo bursts (22) providing position error information retrieved by servo control system (2) having servo gate enabling signal (56). First likely defective burst is identified by reading each burst (22), measuring corresponding position error information and comparing to an acceptable range. While first likely burst retrieval is disabled, position error information from subsequent bursts is measured. If acceptable, the first likely burst becomes the first confirmed burst. If not, bursts before the first likely burst are selectively disabled and measured until a skipped burst is concluded as a first confirmed burst. While first confirmed burst retrieval is disabled, subsequent bursts are measured to find a second likely burst. By selectively disabling retrieval of a second likely burst and measuring, a second confirmed burst is determined. Then the first and second confirmed defective bursts are permanently marked.

Abstract translation: 一种确定写在记录介质上的有缺陷的伺服脉冲串的方法。 位置数据部分（10）包括提供具有伺服控制使能信号（56）的伺服控制系统（2）检索的位置误差信息的伺服脉冲串（22）。 通过读取每个脉冲串（22），测量相应的位置误差信息并与可接受的范围进行比较来识别第一可能的故障突发。 虽然第一次可能的突发检索被禁用，但是测量来自后续脉冲串的位置误差信息。 如果可以接受，则第一个可能的突发成为第一个确认的突发。 如果不是，则在第一可能突发之前的突发被选择性地禁用并测量，直到跳过的突发被确定为第一确认的突发。 虽然第一次确认的脉冲串检索被禁用，但是后续的脉冲串被测量以找到第二个可能的脉冲串。 通过选择性地禁用第二可能突发和检测的检索，确定第二确认突发。 然后第一个和第二个确认的故障突发被永久标记。

公开(公告)号：WO1996039692A1

公开(公告)日：1996-12-12

申请号：PCT/US1996008773

申请日：1996-06-05

Applicant: MAXTOR CORPORATION

Inventor： MAXTOR CORPORATION ,  MATHEWS, Harlan ,  VALENT, James, A.

IPC: G11B05/596

CPC classification number: G11B5/59627 ,  G11B5/3967 ,  G11B5/4886 ,  G11B5/5526 ,  G11B5/5534 ,  G11B5/5547 ,  G11B5/5965

Abstract: The present invention discloses a head positioning system (26) for accurately positioning a read/write head (24) along a selected track (22) of a rotating magnetic disk (20). In one aspect, servo information (64, 68) is embedded along the track (22) with the centerline (72) of the servo information (64, 68) offset a radial distance (88) from the centerline (56) of data stored or written along the track. The head positioning system (26) micro-jogs the read/write head (24) a first (84) and a second (88) radial distance from the centerline of servo information for a read operation (80) and a write operation (76).

Abstract translation: 本发明公开了一种用于沿着旋转磁盘（20）的选定轨道（22）精确定位读/写磁头（24）的磁头定位系统（26）。 在一个方面，伺服信息（64,68）沿着轨道（22）嵌入，伺服信息（64,68）的中心线（72）偏离与存储的数据的中心线（56）的径向距离（88） 或沿轨道写。 磁头定位系统（26）对于读取操作（80）和写入操作（76）从伺服信息的中心线向第一（84）和第二（88）径向距离微读取/写入头部（24） ）。

公开(公告)号：WO1993007612A1

公开(公告)日：1993-04-15

申请号：PCT/US1992008629

申请日：1992-10-09

Applicant: EASTMAN KODAK COMPANY

Inventor： EASTMAN KODAK COMPANY ,  JEFFERS, Frederick, John ,  ROLKER, John

IPC: G11B05/596

CPC classification number: G11B5/596 ,  G11B5/23 ,  G11B5/29 ,  G11B5/584

Abstract: Tracking control apparatus includes a magnetic recording medium (disk or tape) comprising a dedicated servo track having recorded thereon a servo signal having a fixed spatial wavelength, and magnetic playback apparatus comprising a servo tracking head having an elongated tapered transducing gap transverse to the dedicated servo track. The transducing gap has (1) a relatively small magnetic gap length, at a first end of the gap, which is less than the spatial wavelength of the recorded signal, and (2) a relatively large magnetic gap length, at a second opposing end of the gap, which is greater than the spatial wavelength of the recorded servo signal. The servo head is in a desired tracking position when the segment of the tapered gap aligned with the servo track has a magnetic gap length that is equal to the spatial wavelength of the servo signal.

Abstract translation: 跟踪控制装置包括磁记录介质（磁盘或磁带），其包括其上记录有具有固定空间波长的伺服信号的专用伺服磁道，以及包括伺服跟踪头的磁性重放装置，该伺服跟踪头具有横向于专用伺服的细长锥形换能间隙 跟踪。 换能间隙具有（1）在间隙的第一端处小于记录信号的空间波长的相对较小的磁隙长度，和（2）相对较大的磁隙长度，在第二相对端 的间隙，其大于记录的伺服信号的空间波长。 当与伺服轨道对准的锥形间隙的段具有等于伺服信号的空间波长的磁隙长度时，伺服头处于期望的跟踪位置。

公开(公告)号：EP0267771A3

公开(公告)日：1988-11-30

申请号：EP87309902

申请日：1987-11-09

Applicant: SEAGATE TECHNOLOGY, INC.

Inventor： Jacques, James Oliver

IPC: G11B05/596 ,  G11B05/55

CPC classification number: G11B5/5547

Abstract: A system is disclosed wherein a plurality of discs (11) in a stack are accessed using a vertical head array including two servo heads (13), one located at or near each end of the disc stack. In order to exactly center any given data head over a desired data track location in the disc stack, the error distance of the given data head relative to the data track can be determined by combining propor­tions of the two servo head signals from the top and bottom servo heads (131), their proportions being based on the vertical distance of each of the servo heads from the given data head which is to be exactly centered over a data track. If the servo distance from the disc edge is represented by S1 and S2, and the vertical distances from the head to the center of the servo heads is represented by Y1, Y2 then the general formula for calculating the error correction for centering the typical data head is E c =1/Y1+Y2 × (S2Y1+S1Y2).

公开(公告)号：EP0247339A3

公开(公告)日：1988-10-12

申请号：EP87105165

申请日：1987-04-08

Applicant: Hewlett-Packard Company

Inventor： Overton, Wallace H. ,  Knowles, Vernon L. ,  Jackson, Bruce J.

IPC: G11B05/596 ,  G11B21/10

CPC classification number: G11B5/59622

Abstract: Compensation for servo gain variations when connected to different magnetic heads in a disc memory drive is achieved by determining individual servo gain corrections for each magnetic head at several different selected tracks on the associated memory disc, storing the individual servo gain corrections and addressing a stored individual servo gain correction for each selected magnetic head for coupling to the servo to equalize servo gain when positioning each selected magnetic head at a selected track.

公开(公告)号：EP0242887A3

公开(公告)日：1988-01-07

申请号：EP87106964

申请日：1983-11-02

Applicant: NEC CORPORATION

Inventor： Tanaka, Hideo c/o NEC Corporation

IPC: G11B05/58 ,  G11B05/31 ,  G11B05/39 ,  G11B05/596

CPC classification number: G11B5/3903 ,  G11B5/3103 ,  G11B5/3116 ,  G11B5/58 ,  G11B5/5965

Abstract: The magnetic recorder has a pair of first and second transducers (5a,5b) arranged in the longitudinal direction of a record track (6). The magnetic recorder exchanges signals with a magnetic record medium (1) having a servo control signal prerecorded in a lower layer (3a) of said medium (1). A recording circuit (8) is connected to the first transducer (5a) for recording a data signal along the record track (6) in an upper layer (3b) of the medium (1). A reading circuit (9,10) is connected to one of the first and second transducers (5a,5b) for reading the recorded data signal. The second transducer (5b) is connected to a servo control circuit connected for reading the prerecorded servo control signal (12 to 15) and deriving therefrom a position error signal in response to which the position of the transducers (5a,5b) is controlled.