公开(公告)号：DE69126372D1

公开(公告)日：1997-07-10

申请号：DE69126372

申请日：1991-06-26

Applicant: SONY CORP

Inventor： NISHIDA NORIO ,  YAMASHITA YOSHIHIDE

IPC: G11B19/28

Abstract: Disk drive apparatus for reproducing information signal from a disk (1) on which the information signal and a servo sector pulse are recorded, which includes sampling circuit for sampling an output of a counter (9). A speed control signal is generated by detecting a difference between continuous sampling values, and a spindle motor (7) is controlled by the speed control signal. When the rotational speed is slow, the sampling is performed by a detection output for the spindle motor (7), and when the rotational speed is nearly equal to a normal speed, that is performed by the sector pulse.

公开(公告)号：DE69126372T2

公开(公告)日：1997-09-25

申请号：DE69126372

申请日：1991-06-26

Applicant: SONY CORP

Inventor： NISHIDA NORIO ,  YAMASHITA YOSHIHIDE

IPC: G11B19/28

Abstract: Disk drive apparatus for reproducing information signal from a disk (1) on which the information signal and a servo sector pulse are recorded, which includes sampling circuit for sampling an output of a counter (9). A speed control signal is generated by detecting a difference between continuous sampling values, and a spindle motor (7) is controlled by the speed control signal. When the rotational speed is slow, the sampling is performed by a detection output for the spindle motor (7), and when the rotational speed is nearly equal to a normal speed, that is performed by the sector pulse.

公开(公告)号：JP2531177B2

公开(公告)日：1996-09-04

申请号：JP10734687

申请日：1987-04-30

Applicant: SONY CORP

Inventor： TAKAHASHI TADASHI ,  YAMASHITA YOSHIHIDE ,  TAGUCHI KEIICHI

IPC: G11B21/10

公开(公告)号：JPH04143966A

公开(公告)日：1992-05-18

申请号：JP26757590

申请日：1990-10-05

Applicant: SONY CORP

Inventor： YAMASHITA YOSHIHIDE

IPC: G11B19/28 ,  G11B19/20

Abstract: PURPOSE:To constitute the device so that write or read-out can always be executed even if a noise is superposed on a power supply voltage by holding rpmR of a spindle motor and the number of sectors per one track in a prescribed relation. CONSTITUTION:A period T of a power supply voltage VAC is set to 1/60 second and noises No1, No2 are superposed periodically in a prescribed position of a waveform of the VAC. R = [(N + 2)/N] X 3600 is set, the number of sectors SE of a disk 10 increases, rpm approaches 3600, and it is prevented that an access is delayed. Since rpm is quickened by a 2-sector portion or above per one track, it is varied to a sector SE2, and a sector SE4, in accordance with the noise No1 in a first period, and in accordance with the noise No2 in a second period, respectively, and a read operation is executed once excessively and in a second period, the SE2 can be read. Even if the time TO for sending reproduced information to a main computer 2 is taken into consideration, read to the SE2 is completed before the noise No2 is generated and read can be executed by avoiding the influence of the noise No2.

公开(公告)号：JPH04139656A

公开(公告)日：1992-05-13

申请号：JP26215090

申请日：1990-09-28

Applicant: SONY CORP

Inventor： YAMASHITA YOSHIHIDE

IPC: G11B19/28 ,  H02P29/00 ,  H02P29/20

Abstract: PURPOSE:To prevent the fluctuation of the revolving speed of a spindle motor by executing servo-control doubly for the revolving speed of the spindle motor by a signal generated on the basis of a sector signal and the detection of counter electromotive force. CONSTITUTION:The counter electromotive force of the spindle motor 2 is detected by a counter electromotive force detection circuit 10, and the new constant speed revolution of the motor 2 is controlled through a driver 6. Simultaneously, control to rotate the motor 2 at prescribed speed is executed by a signal compensation circuit 8, etc., from the period of a sector pulse reproduced from a disk 9. Through this double servo-control, a disk drive device capable of dealing with the omission of the sector signal is realized.

公开(公告)号：JPS6437774A

公开(公告)日：1989-02-08

申请号：JP19306387

申请日：1987-08-01

Applicant: SONY CORP

Inventor： SATO TSUGUO ,  YAMASHITA YOSHIHIDE

IPC: G11B21/10

Abstract: PURPOSE:To satisfactorily read a servo identification signal by obtaining the servo identification signal of a neighboring servo identification signal recording part as a mutually different frequency. CONSTITUTION:A servo signal recording area 4 and an information signal recording area 3 are mutually provided along a revolving direction on a recording surface 1 of a medium and in the servo signal recording area 4, a servo identification signal recording part 6 is provided to identify a servo signal. Then, for this servo identification signal recording part 6, the frequencies of the servo identification signals of respective recording parts 5 and 6, which are neighbored in a disk diameter direction, are made different mutually. Thus, even when the servo identification signals of the two servo identification signal recording parts, which are neighbored, are simultaneously read, an interference is not generated between these two servo identification signals and the signals can be satisfactorily read with being respectively independent.

公开(公告)号：JPH04355272A

公开(公告)日：1992-12-09

申请号：JP15550691

申请日：1991-05-31

Applicant: SONY CORP

Inventor： YAMASHITA YOSHIHIDE

IPC: G11B20/10

Abstract: PURPOSE:To improve the freedom of setting a clock frequency and the versatility of a drive by generating the clock for detecting a servo signal and the clock for a reading/writing circuit which are necessary for a disk drive. CONSTITUTION:The clock from a source oscillator 1 is supplied to a PLL6. The frequency dividing ratio of the PLL6 is controlled by a control circuit 8. The control circuit 8 receives the information of a servo sector and data sector and a zone from a CPU 3, and supplies a frequency division ratio signal for selectively generating the frequency clock required in a servo signal detection circuit 10 and the frequency clock required in a reading/writing circuit 11 to the PLL6.

公开(公告)号：JPH01196768A

公开(公告)日：1989-08-08

申请号：JP2248888

申请日：1988-02-02

Applicant: SONY CORP

Inventor： YAMASHITA YOSHIHIDE ,  TAKAHASHI TADASHI

IPC: G11B27/10 ,  G11B19/06 ,  G11B19/20

Abstract: PURPOSE:To correctly recognize respective sectors by recording an identifying signal at the leading parts of the respective sectors, generating an index signal from the part to be detected of a turn table through a delay circuit and completely separating the identifying signal. CONSTITUTION:A disk is rotated, an index detector 5 outputs the index signal and this signal is outputted to a servo ID counting circuit 8 through the delay circuit 7. The circuit 8 resets a counter by the index signal to begin to count a servo ID signal. When the index signal is outputted to the circuit 8, since a head 6 is situated at the intermediate position of the data area of the sector, the generation of the signal of the detector 5 and the generation of the servo ID signal are uneven according to various reasons, however, a generation sequence is not reversed. The respective sectors are constantly designated by the same address to correctly recognize.

公开(公告)号：JPS63273283A

公开(公告)日：1988-11-10

申请号：JP10734687

申请日：1987-04-30

Applicant: SONY CORP

Inventor： TAKAHASHI TADASHI ,  YAMASHITA YOSHIHIDE ,  TAGUCHI KEIICHI

IPC: G11B21/10

Abstract: PURPOSE:To surely detect a tracking signal, by extracting the tracking signal from a reproducing signal corresponding to the detection of the change points of different frequency signals in a tracking discrimination signal. CONSTITUTION:The tracking signal consisting of the frequency signals which change continuously and different with each other are recorded in a tracking signal recording area at every sector so as to be arranged in a radius direction on a magnetic disk 1, and the tracking signal is recorded in the tracking signal recording are at every sector so as to follow the tracking discrimination signal. And the change points of the frequency signals in the tacking discrimination signal in the reproducing signal of a magnetic head H are detected by means 5-8, and the tracking signal is extracted from the reproducing signal of the head H based on detected outputs.

公开(公告)号：JPH01119914A

公开(公告)日：1989-05-12

申请号：JP27687687

申请日：1987-10-31

Applicant: SONY CORP

Inventor： TAKAHASHI TADASHI ,  YAMASHITA YOSHIHIDE

IPC: G11B5/596

Abstract: PURPOSE:To attain the accurate formatting of disks in a same recording device by providing a gap width wider than that of a data recording head, and recording and forming servo signal recording patterns through the use of an erase head provided prior to the data recording head in a scanning direction. CONSTITUTION:The gap width of a gap 13 in the erase head is set equal to the recording width WS of servo ID signal patterns 2ID and servo burst signal patterns 2S in a servo area S. At the time of formatting, the position of the magnetic head 11 in the direction of a radius is shifted by a half pitch (p/2) with respect to normal track positions, and the servo ID signal patterns 2ID and the servo burst signal patterns 2S in the servo area S are recorded and formed by the gap 13. While servo signals are reproduced and tracking control is executed, sector ID signal patterns 4 in a data area D are recorded and formed by a gap 12. Thus, accurate formatting is attained without exchanging the disks in the same device.