公开(公告)号：EP0243729A3

公开(公告)日：1988-12-28

申请号：EP87104972

申请日：1987-04-03

申请人： Hewlett-Packard Company

发明人： Bell, R. Frank ,  Wilcox, Roger V.

IPC分类号： G11B05/596 ,  G11B05/55 ,  G11B20/12

CPC分类号： G11B5/5521 ,  G11B5/59627 ,  G11B20/1217 ,  G11B2020/10916

摘要： This method and apparatus for eliminating apparent offset in the servo code adjacent to a guard band on a magnetic memory disc utilizes at least two phases of servo code per magnetic cell for seeking and track centering, or track following, operations and two phases of guard band code per magnetic cell. The two phases of guard band code are each either in phase or similarly out of phase with the respective phases of the servo code in individual magnetic cells. Phase lacking on a selected phase of guard band code is achieved by providing a synchronizing code in the guard band using an irregular pattern of guard band code, providing a timing signal count representing a cell count, for example, decoding the synchronizing code to provide an end of code signal and utilizing the end of code signal and a predetermined cell count signal to achieve phase locking on the correct phase of the guard band code.

公开(公告)号：EP0208054A3

公开(公告)日：1988-01-07

申请号：EP86103210

申请日：1986-03-11

申请人： International Business Machines Corporation

发明人： Jen, Shen ,  Kabelac, William John ,  Sanders, Ian L.

IPC分类号： G11B05/596 ,  G11B05/016

CPC分类号： G11B5/59627

摘要： Servo information is located within one of the data sectors of a record disk and is in the form of a pattern of radially spaced-apart segments (51, 52, 53, 61, 62, 63) , each segment overlapping a number of data tracks and comprising magnetic transitions which increase in frequency with distance from the centre of the disk to provide a digital head position error signal (PES). A similar segment (31, 32, 33) is located in each of the other data sectors around the perimeter of the disk to provide track profile information so that a head positioning system can compensate for disk runout and distortion. The disk drive can include means for eliminating the effect of the amplitude of the readback signal from the servo and profile segments on the head positioning system, thus ensuring a reliable PES at all radial locations on the disk and allowing interchangeability of disks among disk drives.

公开(公告)号：EP0148077A3

公开(公告)日：1985-08-14

申请号：EP84402672

申请日：1984-12-20

申请人： CII HONEYWELL BULL

发明人： Maury, Christian ,  Pinson, Denis ,  Lequien, Jean

IPC分类号： G11B05/596 ,  G11B05/012 ,  G11B21/08

CPC分类号： G11B21/083 ,  G11B5/012 ,  G11B5/59633

公开(公告)号：EP0106661A3

公开(公告)日：1985-08-07

申请号：EP83306177

申请日：1983-10-12

申请人： DYSAN CORPORATION

发明人： Baker, Bradley Donald ,  Kelly, Richard Lawrence

IPC分类号： G11B05/016 ,  G11B05/596 ,  G11B05/55 ,  G11B23/36 ,  G11B27/10

CPC分类号： G11B5/016 ,  G11B5/59627 ,  G11B23/36 ,  G11B27/32

摘要： A method and apparatus for checking performance and alignment of a disk drive designed for use with a floppy disk having a motor (16) driven linear positioning mechanism (14,21) for locating the read/write transducer (22) over the disk circular tracks. A digitally prerecorded diagnostic disk (50) has a series of precisely located special diagnostic tracks providing reference data for various alignment and response characteristics, both mechanical and electronic. A first group of tracks (track 0, 6, 32, 41, 71, 79) have sector ID blocks followed by progressively offset data blocks interspersed therein, with the range of the offset greater than the width of the track for which the disk drive is designed, which guarantees a read failure upon reading any track. These tracks are distributed radially across the surface of the disk at positions corresponding to each rotational phase position of the transducer stepper motor. A pair of indexed timing tracks (track 0, 79) having a fixed number of byte transitions permits testing of both the alignment of the index transducer and skew of the linear positioning device. A pair of special timing tracks affords reference data for head compliance measurement. A plurality of alternate offset tracks (track 44, 47, 50) located centrally of the recording band provides reference data for measuring the eccentricity of the drive spindle.

公开(公告)号：EP0255036A3

公开(公告)日：1988-10-19

申请号：EP87110625

申请日：1987-07-22

申请人： KABUSHIKI KAISHA TOSHIBA ,  Toshiba Computer Engineering Corporation

发明人： Kaida, Katsuhiko c/o Patent Division ,  Asai, Kenji

IPC分类号： G11B20/10 ,  G11B05/012 ,  G11B05/596

CPC分类号： G11B20/10027 ,  G11B20/10 ,  G11B20/10009

摘要： A recorded data reproducing apparatus according to this invention comprises a data pulse generation section (l0 to l5), a peak detection section (l7 to l9) and a control section (20 to 22). The data pulse generation section (l0 to l5) reads out data written on the cylinder of a recording medium on which a magnetic head is currently positioned. According to received gain data, the data pulse generation section (l0 to l5) amplifies a signal corresponding to the readout data, and selectively generates data pulse sequence based on the amplified signal. When the amplified signal corresponds to servo data, the peak detection section (l7 to l9) detects the peak value of the amplified signal. The control section (20 to 22) determines whether or not the magnitude of the detected peak value is nearly equal to a predetermined value. If the determination is nega­tive, the control section (20 to 22) refers to a gain data table to determine a change amount of the gain data, and supplies the gain data updated based on the change amount to the data pulse generation section (l0 to l5).

公开(公告)号：EP0152071A3

公开(公告)日：1988-03-09

申请号：EP85101313

申请日：1985-02-07

申请人： TEAC CORPORATION

发明人： Shoji, Makoto ,  Tsuyuguchi, Hiroshi ,  Toma, Shozo ,  Hiraki, Kazuhiro ,  Morita, Tsutomu

IPC分类号： G11B19/20 ,  G11B21/02 ,  G11B05/596

CPC分类号： G11B19/20 ,  G11B5/5547 ,  G11B19/00 ,  G11B21/106

摘要： A data transfer apparatus for use with a replaceable dislike record medium such as a flexible magnetic'disk having data storage tracks thereon, comprising a disk drive motor for imparting rotation to the record medium, and a head transport motor for transporting a transducer head or heads radially of the record medium so as to enable the transducer head or heads to access the individual data storage tracks on the record medium for data transfer therewith. Also included is a control and drive circuit for controllably energizing the head transport motor. When the disk drive motor is out of rotation, the control and drive circuit holds the supply voltage of the head transport motor zero, or lower than its normal operating voltage for head transportation, for saving power. Then, as the disk drive motor is set into rotation, the control and drive circuit applies the normal operating voltage to the head transport motor preparatory to the commencement of data transfer, thereby automatically recorrecting the head position on the record medium.

公开(公告)号：EP0221740A3

公开(公告)日：1987-11-11

申请号：EP86308294

申请日：1986-10-24

申请人： ADVANCED MICRO DEVICES, INC.

发明人： Gershon, Eugen ,  Sterner, Rudolph J.

IPC分类号： G11B05/596 ,  G11B21/10

CPC分类号： G11B5/59611

摘要： There is disclosed herein a servo data demodulator for use in magnetic head positioning servo system for disk drives. The demodulator is comprised of a single peak detector (32) which detects the maximum amplitude of the peaks in an input signal during specific times. A storage capacitor (34) is used in the peak detector to store the peak level. This peak level is sampled a predetermined number of times during each data frame. Each sample is taken by a different sample and hold circuit (40, 41, 42, 43), and the sequence of the samples is controlled by a timing generator (44, 45, 46, 47). The capacitor (34) of the peak detector is discharged by a switch controlled by the timing generator (58) after each sample and before the next sample. The time delay before the first sample from the start of the frame and the sample time in the sequence is programmable by the user by setting certain inputs into the timing generator (58).

公开(公告)号：EP0130836A3

公开(公告)日：1987-02-04

申请号：EP84304516

申请日：1984-07-02

申请人： MEMOREX CORPORATION

发明人： Rose, Andrew M.

IPC分类号： G11B05/596 ,  G11B21/10

CPC分类号： G11B5/59627

摘要： An apparatus to improve the positioning accuracy of a tracking arm in a disc system is disclosed. The apparatus has acceleration means for moving the arm, braking means to brake the movement of the arm, means for detecting run-out, and responsive means for removing the braking means in the event of run-out detected.

公开(公告)号：EP0265092A3

公开(公告)日：1988-11-30

申请号：EP87308600

申请日：1987-09-29

申请人： KONICA CORPORATION

发明人： Song, Hubert

IPC分类号： G11B05/596 ,  G11B21/10

CPC分类号： G11B5/59655

摘要： A servo system for flexible magnetic disks such that the synchronization pulses do not have to be perfectly aligned. The disk is encoded such that consecutive servo tracks alternate between having a synchronization and an alternate synchronization mark. Four pulses represent a synchronization mark and two pulses represent an alternate synchronization mark. The alternate synchronization marks are off-set from the synchronization marks by a certain distance, such that they do not interfere with each other when a transducer head located between the servo tracks reads them. The disk drive system will read and identify the synchronization marks or alternate synchronization marks and start generating timing signals as appropriate. The servo bursts in the servo sector can then be read.

公开(公告)号：EP0262690A3

公开(公告)日：1988-09-28

申请号：EP87114637

申请日：1983-05-06

申请人： DIGITAL EQUIPMENT CORPORATION

发明人： Sidman, Michael D.

IPC分类号： G11B05/55 ,  G11B05/596

CPC分类号： G11B5/5965 ,  G11B5/5534

摘要： 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.