JPH01196768A - Disk driver - Google Patents

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.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a disk drive device that obtains an index signal as a basis for identifying each sector of a disk from the rotational position of a turntable that rotates the disk.

[Summary of the Invention] The present invention uses a disc in which an identification signal for identifying the sector is recorded at the leading end of each sector in the rotational direction, and a turntable that rotates this disc is provided with an index detection part. In a disk drive device in which a position at which a detection unit detects an index signal and outputs an index signal is set at a gap between adjacent sector areas, the index signal can be outputted by providing a delay means for setting the generation time of the index signal at an intermediate position of one sector. Because the time when the signal is generated and the time when the identification signal is generated are sufficiently far apart,
Each sector can be accurately recognized because the order in which the index signal and identification signal are generated is not reversed due to misalignment between the disc and the turntable.

[Prior Art] FIG. 3 shows an example of a recording format of a disc 1, which is a recording medium. In FIG. 3, a rotation center hole 2 is formed in the center of the disk 1, and a chuck hole 3 is formed in the vicinity thereof. A plurality of sectors L are arranged at predetermined intervals in the circumferential direction of this disk L, and each sector L has a servo area S where servo signals are recorded and a data area S where general data is recorded. has been done. In the servo area S of each sector L, a servo ID signal pattern S is recorded and formed at the beginning of the rotation direction R.

Followed by servo burst signal pattern S! has been recorded. This servo burst signal pattern S has two recording patterns shifted in the circumferential direction and a half pitch P/
They are arranged in a shifted manner. Each sector L
A sector ID signal pattern D for identifying the sector of the data area is recorded at the beginning of the data area in the rotation direction R.

A disk drive device using a disk 1 having such a recording format has a rotating shaft at the center of a turntable, and a chuck bottle 4 protruding from the vicinity of this rotating shaft. The rotation center hole 2 of the disk 1 is inserted into the rotating shaft, and the chuck hole 3 of the disk 1 is inserted into the chuck bin 4, and the disk 1 is positioned and rotated in the circumferential direction with respect to the turntable. In addition, the turntable is provided with one detected part for indexing, and
An index detector is provided on the side for detecting this index detection portion and outputting an index signal.

The position at which this index detector detects the index detection portion (point B position in FIG. 3) is set when the head scanning the track T is located in the gap region Q of the adjacent sector L region. .

As shown in FIG. 4, as soon as the disk 1 rotates and the index signal is output, the servo ID signal is output, and this servo ID signal is output at predetermined time intervals until the disk 1 rotates once. Then, the index signal is output again. The servo ID is set based on this index signal.
It is used to identify in which sector L the head is located by counting the signals. That is, the servo ID signal is also used as an identification signal for each sector L. Then, for example, off-track amount data of the surface circumference of each sector L is stored and used to perform highly accurate tracking based on this information when tracking the next layer.

[Problems to be Solved by the Invention] However, the generation position of the index signal may vary depending on the rotational accuracy of the motor that rotates the turntable, displacement of the threshold value of the index detector due to temperature changes and voltage changes, etc. . This variation is about ±40 to ±80 μs at a rotation speed of 750 rpm, which corresponds to a length of about ±12 to ±13 bytes.

In addition, variations may occur due to the rotation accuracy of the motor that rotates the turntable from the position where the servo [D signal is generated, positional errors between the inner and outer circumferences of the head, and errors due to temperature and voltage changes. This variation is ±2 at a rotation speed of 750 rpm.
It takes about 5 μs, which corresponds to a length of about ±8 bytes. Therefore, when both are combined, the index signal and servo ID
The timing of generation of the signal will vary by about ±20 bytes at most.

Furthermore, if the disk 1 is a floppy disk, the disk 1 is replaced and positional shift occurs due to chucking, which may also cause variations in the timing at which the above-mentioned signal is generated.

Therefore, it is necessary to take these variations into account and maintain a predetermined distance between the index signal generation position and the servo ID signal generation position.
The reality is that we do not have enough distance to reduce waiting times. Therefore, as shown in FIG. 4, each variation ffl N7. Considering Nt, the generation order of the index signal and the servo ID signal is reversed, and the servo ID signal is counted based on the index signal.
) There is a drawback that the order of the signals is shifted by one, and predictive control is performed based on incorrect off-trunk amount data.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a disk drive device in which the order in which index signals and identification signals are generated is always constant.

[Means for Solving the Problems] Disk drive device jN of the present invention for achieving the above object
The system has a plurality of sectors in the circumferential direction, and uses a disk at the beginning of each sector in the rotating direction that records an identification signal to identify each sector.With this disk positioned, the index is placed on a rotating turntable. an index detector for detecting the index detection part and outputting an index signal; In a disk drive device which operates in a gap region between regions, a delay means is provided to set the time point at which the index signal is generated to the middle position of one sector.

[Operation] Therefore, the index signal is delayed by the delay means and can be generated at a time sufficiently distant from the identification signal, so even if the timing of generation of both signals varies depending on the rotation accuracy of the turntable motor, etc. The order of signal generation is never reversed.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

An embodiment of the invention is shown in FIGS. 1 and 2. FIG.

The configurations of the disk 1, the index detection portion, and the index detector used in the disk drive device are the same as those of the conventional example, and therefore their description will be omitted.

In FIG. 1, the index detector 5 detects when the index detected part of the turntable comes to the facing position 1 (the head 6 is at the gap g position between the n-th sector area and the first sector area). An index signal is outputted to the index signal, and this signal is sent to a delay circuit 7 which is a delay means. The delay circuit 7 delays the index signal by a predetermined time T and outputs the index signal. When the head 6 reaches the middle position of the first sector area, more specifically, the data area, the index signal is output to the servo. Output to rD counting circuit 8. Note that the predetermined time T needs to be changed depending on the number of rotations of the disk l.

Also, a head 6 for reading the recording pattern on the disk l.
is configured to be movable in the radial direction (R direction) of the disk 1 by a head actuator 9. This output signal from the head 6 is output to a servo ID detector lO and an off-track amount detector 11, respectively. A servo ID detector 10 picks up a servo ID signal from the output signal of the head 6 and sends this servo ID signal to the servo D counting circuit 8, the off-track amount detector 11, and the off-track amount memory 12. The target ID counting circuit 8 counts the servo ID signal using the index signal of the delay circuit 7 as a reset signal, and supplies this count data to the servo circuit 13 and the off-track amount memory I2. The off-track amount detector 11 obtains off-track amount data from a pair of servo burst signals S sent from the head 6 after a predetermined time of the servo ID signal. That is, since the head 6 that scans the track T scans a pair of servo burst signals S that are arranged half a pitch apart on both sides of the track T, the amount of off-trunk is determined depending on the ratio of these reproduction bells, etc. Data is obtained. This off-track amount data is supplied to a servo circuit 13 and an off-track amount memory 12. The off-track amount memory 12 uses the servo ID signal as a timing signal, uses the count data from the servo ID counting circuit 8 as an address, and uses the off-track amount data sent from the off-track amount detector 11 immediately after this count data as an address. Self-memory - 4. This stored data is updated every round.

The servo circuit 13 outputs a head movement command to the head actuator control circuit 14 based on the off-track m data when scanning the periphery of a certain track T, and outputs a head movement command to the head actuator control circuit 14 when scanning the second and subsequent layers. Based on the data, off-track m data is read from the off-track amount memory 12, and a head movement command is output to the head actuator control circuit 14 based on this off-track amount data.

The head actuator control circuit I4 gives a drive signal to the head actuator 9 in response to a head movement command, and the head actuator 9 moves the head 6 in the radial direction (toward direction) of the disk 1.

The operation of the above configuration will be explained below.

As shown in FIG. 2, when the turntable rotates and the index detector 5 detects the index detection portion (point B in FIG. 3), an index signal is output to the delay circuit 7. The delay circuit 7 outputs an index signal to the servo ID counting circuit 8 after a predetermined time T has elapsed, and the servo [D counting circuit 8 resets the counter by this signal.

On the other hand, the reproduction signal from the head 6 is sent to the servo ID detector 10.
and off-trunk detection 'rj, sent to 11, servo I
The servo ID signal of each sector L is sequentially output from the D detector IO to the servo counting circuit 8, and the off-track amount data is output from the off-track amount detection 1 to the servo circuit 13 and the off-track amount memory 12. . The servo ID counting circuit 8 counts this servo ID signal, and this count data is sent to the off-track amount memory 12. The off-track m memory 12 stores off-track amount data as shown in the table below using count data as an address signal.

When the disk l rotates once and enters the second layer, the index detector 5 outputs an index signal again, and this index signal is output to the servo ID counting circuit 8 via the delay circuit 7. The servo ID counting circuit 8 resets the counter with the index signal and starts counting the servo ID signals again.

At the time when the index signal is output to the servo ID counting circuit 8, the head 6 is at an intermediate position between the data area of sector L. Even if the time of occurrence varies for various reasons, the order of occurrence will not be reversed.

Therefore, each sector L is always designated by the same address, and the servo circuit 13 controls the tracking position using accurate off-trunk amount data from the previous layer.

In this embodiment, the delay circuit 7 is configured to output the index signal in the first sector L area and at the center of the data area, but the index signal of the index detector 5 and the servo ID detection The position may be any position as long as the order of generation is not reversed, taking into consideration the respective variations with respect to the servo ID signal of the device 10. In addition, if the disk drive device can use a plurality of disks 1 having different sector L lengths, the generation order of the index signal and servo ID signal for each disk 1 should be adjusted in consideration of the interval between the servo ID signals of each disk 1. The position should not be reversed.

Further, in this embodiment, the servo ID signal is used as the identification signal for addressing each sector 7, but other signals may be used as the identification signal.

[Effects of the Invention] As described above, according to the present invention, a disc in which an identification signal for identifying the sector is recorded at the beginning of each sector in the rotational direction is used, and a turntable that rotates this disc is provided with an index cover. In a disk drive device in which a detection section is provided and the position at which the detected section for indexing is detected and the index signal is outputted is set as a gap between the areas of adjacent sectors, the time when the index signal is generated is set at an intermediate position between the sectors. Since the delay means is provided, there is a sufficient distance between the generation of the index signal and the generation of the identification signal, so that the order in which the index signal and identification signal are generated is reversed due to reasons such as misalignment between the disc and the turntable. This has the effect that each sector can be accurately recognized without becoming erroneous.

[Brief explanation of the drawing]

FIG. 1 is a circuit block diagram of an embodiment of the present invention, and FIG.
The figures are diagrams showing the output signals of each part, FIG. 3 is a diagram showing the recording format of the disk, and FIG. 4 is an output waveform diagram of a conventional example. l...disk, 5...index detector, 6...
Head, 7: Delay circuit (delay means), L: Sector, e: Gap area between sector areas.

Claims (1)

[Claims] (1) A plurality of sectors are provided in the circumferential direction, and a disk on which an identification signal for identifying each sector is recorded is used at the beginning of each sector in the rotating direction. With this disk positioned, it is indexed onto a rotating turntable. an index detector for detecting the index detection part and outputting an index signal; What is claimed is: 1. A disk drive device configured to operate in a gap region between regions, further comprising a delay means for setting the time point at which the index signal is generated to a middle position of one sector.