Head positioning apparatus for a magnetic disc device

Claim 3

The system claimed in claim 1 characterised in that the compensating means comprise, in sequence, rectifying means (14), integrating means (15) providing an analog signal (F), an analog-digital converter (16), and compensating circuitry (17) for computing the displacement on the basis of the digital output (G) and generating a head position-compensating signal.

Claim 4

A disk device for positioning a head (3) for reading/writing information from /on a selected data track of a plurality of data tracks (10) concentrically formed on a disk (1) thereof, comprising: a disk drive motor (2), an index timing sensor (7) for detecting an index provided on a rotary unit of said motor at every revolution and feeding a timing signal for notifying a starting point of a position information recording area (11) to position displacement compensating control means (17). position information means (S ,5 )provided over a predetermined radial area (11) on said disk and having a predetermined pattern for generating different pieces of information in accordance with the position displacement of the head (3) from the central position of the selected track, operating means (4) for detecting the said different pieces of information from said position information means, feeding the information as analog signal to rectifying means,(14) and moving said head in a direction transverse to said data track, a positioning device (5) for driving said operating means, (4) and said position displacement compensating control means (17)_receiving as input the said different pieces of information from said position information means, converted to digital signals by A/D convertor means (16) for converting the analog signal fed from said rectifying means (14) through an integrating means (15) into digital signals in coincidence with the timing signal from said index timing sensor (7), and feeding the output approximated to zero when the head position corresponds to the central position of the data track, as a position compensating output for controlling said positioning device (5).

Claim 5

A disk device for positioning a head (3) for reading/writing information from /on a selected data track of a plurality of data tracks (10) concentrically formed on a disk (1) thereof, comprising: a disk drive motor (2), an index timing sensor (7) for detecting an index provided on a rotary unit of said motor at every revolution and feeding a timing signal for notifying a starting point of a position information recording area (11) to position displacement compensating control means (17). position information means (S ,5 )provided over a predetermined radial area (11) on said disk and having a predetermined pattern for generating different pieces of information in accordance with the position displacement of the head (3) from the central position of the selected track, operating means (4) for detecting the said different pieces of information from said position information means, feeding the information as analog signal to rectifying means,(14) and moving said head in a direction transverse to said data track, a positioning device (5) for driving said operating means, (4) and said position displacement compensating control means (17)_receiving as input the said different pieces of information from said position information means, converted to digital signals by A/D convertor means (16) for converting the analog signal fed from said rectifying means (14) through an integrating means (15) into digital signals in coincidence with the timing signal from said index timing sensor (7), and feeding the output approximated to zero when the head position corresponds to the central position of the data track, as a position compensating output for controlling said positioning device (5).

Claim 6

A disk device as claimed in claim 3 wherein said operating means (4) comprises an actuator.

Claim 7

A disk device as claimed in any preceding claim wherein the position information comprises two flux-reversal parts (12a, 12b) provided corresponding to both sides of the data track, and the head is a magnetic head.

Claim 8

A disk device as claimed in claim 5 wherein the two flux-reversal parts (12a, 12b) have a pitch equal to the interval of the data tracks, are respectively displaced by half the pitch of the data tracks on both sides of the data track, and the parts (12a, 12b) are displaced longitudinally of the data track so as not to be superposed on each other.

Claim 11

A disk device for positioning a head (3) for reading/writing information from or on an arbitrary data track of a plurality of data tracks concentrically formed on a disk (1) thereof, comprising: a disk drive motor (2), an index timing sensor (7) for detecting an index provided on a rotary unit of said motor at every one revolution and feeding a timing signal for notifying a starting point of a position information recording area (11) to a presumed position displacement output means (17p). said presumed positioned displacement output means (17p) for outputting presumed position displacement to the data track except the both end sides on the basis of position information (S 1 ,S 2 ) output provided over the radial area on the data track disposed at least at both end sides of a plurality of data tracks on said disk, said head (3) for detecting different pieces of information from said position information means and feeding the same as analog signals to rectifying means (14), operating means (4) for detecting different pieces of information from said position information means, feeding the information as analog signals to rectifying means (14) and moving said head in a direction crossing the extension of said data track, a positioning device (5) for driving said operating means (4), and position displacement compensating means for inputting presumed position displacement from said presumed position displacement output means for inputting different pieces of information from said position information means that are converted to the digital signals by A/D converter means for converting analog signals fed from said rectifying means through integrating means into digital signals, and controlling said positioning device.

Claim 12

A disk device for positioning a head (3) for reading/writing information from or on an arbitrary data track of a plurality of data tracks concentrically formed on a disk (1) thereof, comprising: a disk drive motor (2), an index timing sensor (7) for detecting an index provided on a rotary unit of said motor at every one revolution and feeding a timing signal for notifying a starting point of a position information recording area (11) to a presumed position displacement output means (17p). said presumed positioned displacement output means (17p) for outputting presumed position displacement to the data track except the both end sides on the basis of position information (S 1 ,S 2 ) output provided over the radial area on the data track disposed at least at both end sides of a plurality of data tracks on said disk, said head (3) for detecting different pieces of information from said position information means and feeding the same as analog signals to rectifying means (14), operating means (4) for detecting different pieces of information from said position information means, feeding the information as analog signals to rectifying means (14) and moving said head in a direction crossing the extension of said data track, a positioning device (5) for driving said operating means (4), and position displacement compensating means for inputting presumed position displacement from said presumed position displacement output means for inputting different pieces of information from said position information means that are converted to the digital signals by A/D converter means for converting analog signals fed from said rectifying means through integrating means into digital signals, and controlling said positioning device.

Claim 13

A disk device having a disk, a head facing said disk for reading/writing information, a positioning motor for positioning said head, positioning control means for controlling said positioning motor and detecting a reference track, and an index timing sensor for feeding to said position means a timing signal necessary for positioning to read/write the information, said disk comprising data track areas having a plurality of tracks sequentially concentrically arranged radially thereon, guard band areas having read only track areas of the information at the outer periphery of said data track areas, and position information areas for recording, on a part of the tracks of said data track areas and said guard band areas position information for distinguishing whether the disk opposite positions of said head is disposed on said data track areas or said guard band areas, said positioning control means for detecting track 0 as the reference track controlling the positioning motor to dispose said head on said data track areas by the position information of said position information areas read by said head in coincidence with the timing signal from said index timing sensor, then moving said head to said data track areas, and detecting that the position information of said position information areas are changed from the position information of said guard band area to the position information of said data track areas in order to detect track 0 as a reference track.

Claim 14

A disk device having a disk, a head facing said disk for reading/writing information, a positioning motor for positioning said head, positioning control means for controlling said positioning motor and detecting a reference track, and an index timing sensor for feeding to said position means a timing signal necessary for positioning to read/write the information, said disk comprising data track areas having a plurality of tracks sequentially concentrically arranged radially thereon, guard band areas having read only track areas of the information at the outer periphery of said data track areas, and position information areas for recording, on a part of the tracks of said data track areas and said guard band areas position information for distinguishing whether the disk opposite positions of said head is disposed on said data track areas or said guard band areas, said positioning control means for detecting track 0 as the reference track controlling the positioning motor to dispose said head on said data track areas by the position information of said position information areas read by said head in coincidence with the timing signal from said index timing sensor, then moving said head to said data track areas, and detecting that the position information of said position information areas are changed from the position information of said guard band area to the position information of said data track areas in order to detect track 0 as a reference track.

Claim 15

A disk device as claimed in claim 9 wherein said positioning motor is a stepping motor.

Claim 16

A disk device as claimed in claim 9 or 10 wherein the position information of said data track areas has two flux-reversal areas and non-flux-reversal areas provided at both sides of the data tracks, and the position information of a pair of said guard band areas has a flux-reversal area and a non-flux-reversal area.

Claim 17

A disk as claimed in claim 11 wherein the two flux reversal areas of said data tracks areas are equal to the interval of the data track, displaced by half pitch of the interval of the data tracks at both sides of the data tracks, displaced in the widthwise direction of said disk so as not to be superposed to each other, and track 0 is continued to the flux-reversal area radially extending of said guard band area.