JPH03216874A - Rotary recording disk device - Google Patents

Abstract

PURPOSE:To perform the run-out correction most suitable for each zone by selectively inputting and outputting run-out information at a timing corresponding to the number of sectors. CONSTITUTION:A zone detecting circuit 2 has a function to detect the zone where a head is placed at present, and detected zone information is used as selecting information of a zone-classified run-out table circuit 3 and a run-out timing signal generating circuit 5. A run-out measuring circuit 4 measures the extent of positional deviation of a servo sector based on information of the sector in accordance with the timing clock and stores the extent of correction corresponding to this extent in the run-out table of the zone-classified run-out table circuit 3. The position error correction value corresponding to the zone where the head exists and the output timing of the extent of correction are selectively outputted. Thus, run-out information corresponding to the zone is individually gathered, and run-out correction is performed with the extent of correction most suitable for each zone.

Description

[Detailed Description of the Invention] This invention relates to a rotary recording disk device for controlling a disk drive in a magnetic disk device such as a hard disk or a floppy disk, or an optical disk device. The positional error (runout) caused by the deviation between the center of rotation of the recording recorder and the center of the track is measured in advance, and a signal for correcting the runout is output to the head positioning means based on the positive positional error information to perform correction drive. This paper relates to a rotating recording disk device that enables highly accurate runout correction. Previously, in magnetic disk devices such as hard disks and floppy disks, especially in recording devices with removable recording media, it is necessary to control the positioning of the read/write head within one revolution on the recording track of the disk. One or more servo signal recording areas are provided to record servo information (servo patterns).

For such servo information, in the case of a disk with a relatively low recording density, it is sufficient to provide one servo signal recording area within one revolution on the recording track, and for example, index servo is used to control the positioning of the magnetic head. will be held.

However, as the recording density increases, it is necessary to increase the control accuracy, so a plurality of servo signal recording areas are provided within one revolution on the recording track, and positioning control is performed using, for example, sector servo. FIG. 4 is a diagram showing an example of a sector arrangement on a recording track on a magnetic disk, in which (1) is an index signal, (2) is the state of sectors arranged between index signals, and (3) is one FIG. 3 is a diagram showing details of sectors of FIG.

This fourth Wi shows the case of magnetic head positioning control using sector servo.

As shown in (2) of Fig. 4, on the recording track,
In order to store user data of a predetermined length, multiple sectors, ie, "sector 1", "sector 2", etc.
..., "sector m" is arranged.

As shown in (3) in FIG. 4, each sector includes a synchronization signal section where a synchronization signal of a predetermined bit pattern is arranged, a servo information section where servo information consisting of a double-bit signal is arranged, and a servo information section where servo information consisting of a double-bit signal is arranged. It consists of an identification signal section in which a sector address for identifying a sector, flag information indicating the state of the sector, etc. are arranged, and a data section for storing a predetermined length of user data.

The index signal shown in (1) in FIG. 4 is a signal indicating the reference position of the recording track. In this way, magnetic disk drives that perform positioning control based on servo information recorded on the disk surface generally use a so-called burst-like double-bit signal (servo burst signal), which is a signal sequence recorded with different off-track amounts. ) has been adopted. By the way, in such a recording device where the recording medium can be easily removed, there is a possibility that the rotation center of the rotating means for rotating the recording medium may be misaligned with the center of the pre-recorded track. Correction of errors (runout) has become an extremely important function as track density increases. The reason for this is that as a method of increasing the density in the rotation direction, for example, recording is performed so that more information can be recorded on the outer circumference than the conventional constant bit number recording method that keeps the number of bits constant for the rotation angle. This is because a bit number changing recording method has appeared in which the frequency is changed or the rotation speed is slowed on the outer circumference side.

With the advent of such a recording method, the number of sectors for each track increases toward the outer circumference and decreases toward the inner circumference. That is, the number of sectors for each track is no longer constant for all tracks.

As a result, the spacing and number of servo information for positioning the head vary from track to track, making run-out correction even more difficult, resulting in the inconvenience that traditional methods cannot accurately control head positioning. .

This invention aims to solve these problems in conventional rotary recording disk devices, namely, as the track density increases, the spacing and number of servo information for positioning the head vary from track to track. This solves the problem of making runout correction even more difficult and making accurate head positioning control extremely difficult, and makes it possible to perform accurate runout correction even when the spacing and number of servo information differs from track to track. The purpose of the present invention is to provide a rotating recording disk device.

Specifically, first, a group with the same number of sectors in one round is considered to be one zone, and runout information (runout data) corresponding to each zone is collected separately for each zone, and the optimal data for each zone is collected. It is an object of the present invention to provide a rotary recording disk device capable of performing run-out correction using a correction amount.

Second, by determining the position error correction value in one specific zone (especially the outer zone) and correcting the runout based on this position error correction value when driving other zones, it is easy and accurate. The purpose of this invention is to provide a rotating recording disk device that can perform run-out correction. Firstly, this invention has a plurality of concentric tracks, one track is divided into a plurality of sectors, and a method for positioning the head at the beginning of each sector. In a rotating recording disk device that has servo information and is divided into multiple zones with different numbers of sectors per track, the position error caused by the misalignment between the center of rotation of the recording disk and the center of the track can be measured in advance. means for outputting a signal for correcting runout to the head positioning means based on the position error information to perform correction driving; means for detecting each zone; and a plurality of units for storing position error correction values for each zone. It is configured to select and output a position error correction value according to the zone in which the head is present and the timing for outputting the correction value.

Second, it has a plurality of concentric tracks, one track is divided into a plurality of sectors, and has servo information for positioning the head at the beginning of each sector, and In a rotating recording disk device divided into a plurality of zones with different numbers of sectors per track, a position error measuring means for measuring in advance a position error caused by a deviation between the rotation center of the recording disk and the center of the track; means for outputting a signal for correcting runout to the head positioning means to perform correction drive based on the position error information obtained by the position error measuring means, and determining a position error correction value in one specific zone. , when driving other zones, the runout is corrected based on the position error correction value. Next, embodiments of the rotary recording disk device of the present invention will be described in detail with reference to the drawings. In this embodiment, a group with the same number of sectors per round is treated as one zone, and runout information corresponding to each zone is collected separately for each zone, so that runout correction can be performed with the optimal correction amount for each zone. ing. FIG. 1 is a functional block diagram showing an embodiment of the main structure of a rotary recording disk device of the present invention. In the drawings, 1 is a head section, 2 is a zone detection circuit,
3 is a zone-by-zone runout table circuit, 4 is a runout measurement circuit, 5 is a runout timing signal generation circuit, and 6 is a head drive circuit. The operation of the block diagram in FIG. 1 is as follows.

The head section 1 is composed of a magnetic head, etc., and has a function of reading/writing information recorded in a recording disk device. The zone detection circuit 2 has a function of detecting which zone the head is currently located in.

For this purpose, zone information is added and written in advance to the servo information on the recording track as shown in the fourth @. Note that the head position may be detected using another sensor instead of the zone information, and it is not always necessary to use the zone information. The zone information detected by the zone detection circuit 2 is used as selection information for the zone-by-zone runout table circuit 3 and the runout timing signal generation circuit 5. That is, the zone detection circuit 2 causes the runout timing signal generation circuit 5 to output a timing clock in accordance with the timing of the zone in which the head is located. In addition, the runout measurement circuit 4 measures the positional deviation amount of the sector from the servo sector information in accordance with this timing clock, and stores the corresponding correction amount in the runout table of the zone-by-zone runout table circuit 3. .

The runout timing signal generation circuit 5 generates a timing clock signal for outputting the runout measurement timing and the correction amount calculated based on the measured data to the head drive circuit 6 according to the input selection signal. It has the function of generating.

Head drive circuit 6 drives head section 1 .

Next, the run-out correction driving operation of the rotary recording disk device of the present invention shown in FIG. 1 will be specifically explained.

In the following explanation, as an example, it is assumed that one revolution is divided into 12 servo sectors. The runout amount in this case can be approximated to a sine wave of one cycle.

Correction driving is performed by sequentially outputting to the timing clock information on correction amounts for correcting positional errors stored in the runout table of the zone where the head is located.

FIG. 2 is a diagram showing an example of a time chart for explaining the control operation of correction drive based on runout information in the rotary recording disk device of the present invention shown in FIG. (2) shows the timing clock signal output from the runout timing signal generation circuit 5, (3) shows the calculated correction amount, and (4) shows the corrected drive signal.

In the rotary recording disk device of the present invention, a positional error caused by a deviation between the center of rotation of the recording disk and the center of the track is measured in advance.

In this case, a runout amount as shown in FIG. 2(1) is generated.6 Such a runout amount is captured at the timing shown in FIG. 2(2) to obtain position error information.

This position error information is stored in each table in the zone-by-zone runout table circuit 3.

During actual driving, a signal for correcting run-out as shown in FIG. 2 (3) is generated based on the position error information for each zone previously stored in each table and output to the head positioning means. .

Therefore, as shown in FIG. 2 (4), accurate correction driving is performed.

Therefore, according to the correction drive according to the first embodiment, even if there are a plurality of zones with different numbers of servo sectors in one rotation, information on the optimum correction amount can be obtained for each zone, so that run-out can be avoided. Accurate correction driving becomes possible.

As described above, according to this embodiment, even if the rotary recording disk has multiple zones with different numbers of servo sectors, input and output of runout data can be selectively performed at timings according to the number of sectors. By doing so, it becomes possible to perform optimal runout correction for each zone.

Next, another embodiment of the rotary recording disk device of the present invention will be described. The difference between this embodiment and the previous first embodiment is that in the case of the previous embodiment, runout information is collected for each zone by treating a group with the same number of sectors in one rotation as one zone. , it takes too much time to collect runout information, and
Whereas the number of samples decreases toward the inner circumference and the resolution deteriorates, in this second embodiment, the runout information (position error correction value) of one specific zone, for example, one zone on the outside with a large number of samples, is By using this method to perform run-out correction driving for all tracks, the information collection time is shortened and the resolution is improved.

In this way, in this second embodiment, a position error correction value is obtained in one specific zone (especially the outer zone), and runout is corrected based on this position error correction value when driving other zones. This makes it possible to perform runout correction easily and accurately.

FIG. 3 is a functional block diagram showing the main part configuration of another embodiment of the rotary recording disk device of the present invention. In the drawings, 11 is a head section, 12 is a runout measurement circuit, 13 is a correction table, 14 is an output timing signal generation circuit, 15 is a positioning correction circuit, 16 is an adder, and 17 is a head drive circuit.

The runout measurement circuit 12 has a function of measuring the runout of a specific zone and storing the correction value in the correction table 13.

The output timing signal generation circuit 14 uses the correction table 13
It has a function of outputting correction value information stored in the disk in synchronization with the rotation of the disk.

The positioning correction circuit 15 has a function of outputting the amount of positional deviation determined from the servo information where the servo information is present.

The adder 16 adds the correction value read from the correction table 13 and the positional deviation amount output from the positioning correction circuit 15 and outputs the result to the head drive circuit 17. Note that the head section 11 and the head drive circuit 17 are similar to the first one described above.
It is similar to the figure.

As already mentioned, in this embodiment, the correction amount for each sector is determined from the head-off track amount in the runout measurement zone.

When performing positioning control for different zones,
Information on the amount of correction is output using the timing clock generated from the output timing signal generation circuit 14, and the positional deviation resulting from this correction driving is read from the servo information of that zone to obtain information on the amount of correction actually used. Correct again.

In the case of this second embodiment, the rotary recording disk device of the present invention performs the correction drive as described above.

Therefore, according to the rotary recording disk device of the present invention shown in FIG. 3, run-out correction driving can be performed with higher precision by using a correction table for a track with a high sampling frequency.

Furthermore, run-out correction driving is possible with one correction table. Furthermore, in order to improve the resolution of the correction drive, it becomes possible to provide a separate track for runout correction without a data area. In this way, in this second embodiment, a positional error correction value is obtained for one specific zone, and runout is corrected based on this positional error correction value when driving other zones.

According to the rotary recording disk device of this invention, firstly,
Even when a rotating recording disk has multiple zones with different numbers of servo sectors, optimal performance is achieved for each zone by selectively inputting and outputting runout information at timings according to the number of sectors. Since accurate runout correction becomes possible, the accuracy of disk drive control is significantly improved (an effect corresponding to claim 1).

Second, by using a correction table for a track with a high sampling frequency for run-out correction driving, more accurate correction driving becomes possible. Thirdly, in this case, with one correction table,
Runout correction drive becomes possible. Fourthly, it is possible to separately provide a run-out correction track without a data area in order to improve the resolution of correction drive (effect corresponding to claim 2), and many other advantages. The effect is produced.

[Brief explanation of drawings]

FIG. 1 is a functional block diagram showing an embodiment of the main configuration of the rotary recording disk device of the present invention, and FIG. FIG. 3 is a diagram showing an example of a time chart for explaining the control operation of the correction movement based on runout information. FIG. FIG. 4 is a diagram showing an example of a sector arrangement on a recording track on a magnetic disk. In the drawing, 1 is a head part, 2 is a zone detection circuit, and 3 is a head part.
is a zone-by-zone runout table circuit, 4 is a runout measurement circuit, 5 is a runout timing signal generation circuit,
6 is a head drive circuit.

Claims (1)

[Claims] 1. It has a plurality of concentric tracks, one track is divided into a plurality of sectors, and the head of each sector has servo information for positioning the head. ,
In a rotary recording disk device that is divided into multiple zones with different numbers of sectors per track, the position error caused by the deviation between the center of rotation of the recording disk and the center of the track is measured in advance, and the position means for outputting a signal for correcting runout based on the error information to the head positioning means to perform correction driving; means for detecting each zone; and a plurality of tables for storing position error correction values for each zone. A rotary recording disk device comprising: selecting and outputting a positional error correction value according to a zone in which a head exists and a timing for outputting the correction value. 2. It has a plurality of concentric tracks, one track is divided into a plurality of sectors, and has servo information for positioning the head at the beginning of each sector,
Position error measurement that measures in advance the position error caused by the misalignment between the center of rotation of the recording disk and the center of the track in a rotating recording disk device that is divided into multiple zones with different numbers of sectors per track. and means for outputting a signal for correcting runout to the head positioning means to perform correction drive based on the position error information obtained by the position error measuring means, A rotary recording disk device characterized in that an error correction value is determined, and when driving other zones, runout is corrected based on the position error correction value.