JPH0350355B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a magnetic disk and a sector determination method for a magnetic disk, which selects and erases a group of head positioning information on a disk-shaped magnetic recording medium. It is related to.

[Conventional technology]

FIG. 4 is a recording state diagram of a magnetic disk used in a conventional magnetic disk device, where a shows an 8-sector magnetic disk, b shows a 12-sector magnetic disk, 16 is a magnetic disk, 17 is a magnetic disk, and FIG. is track 1 on the outer circumferential side, 18 is track 2, 1 on the center part.
9 is inner track 3, 20 is magnetic disk 1
This is a group of head positioning information that is narrowly recorded between each sector so as to expand outward in the radial direction of 6. Next, the operation of positioning the magnetic head using the head positioning information group 20 in this type of magnetic disk device will be explained with reference to the drawings.

FIG. 5 is a diagram showing a head positioning method in this type of magnetic disk device, in which 21 is a positioning information group a, 22 is a positioning information group b, 23 to
27 is the trajectory of the magnetic head that is gradually positioned to the center position of the track. The head positioning information group 20 is composed of a positioning information group a21 and a positioning information group b22 arranged alternately, and the boundary between the positioning information group a21 and the positioning information group b22 is approximately the same as each track 17, 18, 19. In the center. In reality, the magnetic disk 16 is moving in the circumferential direction of the arrow A in the figure, and the magnetic head is only moving in the radial direction of the magnetic disk 16 perpendicular to the arrow A.

Positioning of the magnetic head is performed by comparing the magnitude of the voltage of the positioning information group a21 read every time the magnetic head detects the positioning information group 20 with the voltage of the positioning information group b22, and moving the magnetic head in the direction where the magnitudes are equal. This is achieved by sequentially repeating movements by minute amounts.

More specifically, the figure shows the positioning of the magnetic head on the track 218. When the magnetic head is at positions 23 and 24, the magnetic head reads the head positioning information group 20, and the read voltage of the positioning information group a21 is higher than the read voltage of the positioning information group b22, so the magnetic head It is determined that the magnetic head is shifted toward the outer circumference, and therefore the magnetic head is moved from position 23 to position 24 and from position 24 to position 25 by a minute amount toward the inner circumference. Conversely, when the magnetic head is at position 25, when the magnetic head reads the head positioning information group 20, the read voltage of the positioning information group b22 is greater than the read voltage of the positioning information group a21, so the magnetic head It is determined that the head has shifted toward the inner circumference, and therefore the magnetic head is moved from position 25 to position 26 by a minute amount toward the outer circumference.

Also, at position 26 of the magnetic head, track 2
18, and while the magnetic head reads the head positioning information group 20, the positioning information group a
Since the read voltage of the positioning information group b21 and the read voltage of the positioning information group b22 are equal, the read voltage of the positioning information group b22 is the same.
It is determined that the positioning on 18 is completed, and therefore the magnetic head is moved from position 26 to position 2 without moving the magnetic head.
Make it 7.

[Problem that the invention seeks to solve]

The magnetic disk used in this type of conventional magnetic disk device preferably has a group of head positioning information recorded in the sector type desired by the user.
However, the positioning information group is recorded by a positioning information writing device, and since this device is generally expensive, users of magnetic disks do not own it, and general users write the desired sector type in advance. A magnetic disk is obtained with a group of head positioning information recorded on it. For this reason, the user must always have a wide variety of sector-type magnetic disks on hand, resulting in the problem of inefficient use of the magnetic disks.

This invention was made to solve the above-mentioned problems, and provides a magnetic disk and a method for determining sectors of the magnetic disk that can be modified by the user to a desired sector type when using the magnetic disk. The purpose is to obtain.

[Means for solving problems]

The magnetic disk according to the present invention has a plurality of types of sector-type head positioning information groups recorded on the recording surface.

The sector determination method for a magnetic disk according to the present invention involves preparing a magnetic disk on which a plurality of types of sector-type head positioning information groups are recorded in advance;
When used, a group of head positioning information that is no longer needed for a desired sector type is erased by the magnetic head.

[Effect]

The magnetic disk and magnetic disk sector determination method of the present invention can change the magnetic disk to a desired sector type by a simple operation of erasing unnecessary head positioning information on the magnetic disk by energizing the magnetic head. , it is possible to improve the utilization efficiency of magnetic disks.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a recording state diagram of a magnetic disk showing an embodiment of the present invention. In the figure, the same reference numerals as in the conventional example indicate corresponding parts, and 1
6a, 16b, 16c are magnetic disks, 17 is track 1, 18 is track 2, 19 is track 3, 20 is a head positioning information group, and a in the figure is 8 sector type, 12 sector type, 4 sector type, and 6 sector type. FIG. 4B shows a magnetic disk 16a on which four types of sector-type head positioning information groups 20 are recorded, and FIG. A magnetic disk 16b is shown, and FIG. 1c shows a 12-sector magnetic disk 16c obtained in the same manner. In FIG. 1a, among the head positioning information group 20 for 8 sectors and the head positioning information group 20 for 12 sectors, four head positioning information groups 20 that are at 90 degrees to each other are for 8 sectors and 12 sectors. It is shared for use. If the center line of one of the four head positioning information groups 20 is taken as a reference at 0°, the center lines of the other head positioning information groups 20 are
30°, 45°, 60°, 90°, 120°, 135°, 150°, 180,
Sixteen head positioning information groups 20 are arranged on the magnetic disk 16a so as to form angles of 210°, 225°, 240°, 270°, 300°, 315°, and 330°.

Here, the unnecessary group of head positioning information is erased by passing a recording current in a fixed direction to the magnetic head while the magnetic head passes over the unnecessary group of head positioning information. This erasing method is generally called DC erasing.
Hereinafter, the erasing method will be specifically explained using figures.

FIG. 2 is an explanatory diagram showing a method of erasing the head positioning information group 20 that is no longer needed in the head positioning information group 20 in FIG. The unnecessary head positioning information groups 2 to 9 are the magnetic heads that are positioned sequentially from the smallest number to erase the unnecessary head positioning information group 1 in the head positioning information group 20 of the head positioning information group 20. (The gap is assumed to extend over the entire width of the magnetic head.) Reference numeral 10 denotes an erase command signal for direct current erasing which is applied to the magnetic heads 2 to 9 in order to erase the unnecessary head positioning information group 1. While the erase command signal 10 is at a high level, the unnecessary head positioning information group 1 is erased.

Here, the head positioning information group 20 is generally recorded seamlessly in the radial direction of the magnetic disk, and on the other hand, the widths erased by the magnetic heads 2 to 9 are generally tracks 1 to 3, 17 to 1, respectively.
Each track spacing is narrower than 9. For these reasons, in order to erase unnecessary head positioning information group 1, it is necessary to position the magnetic heads at intervals narrower than the track intervals, and magnetic heads 2 to 9 are positioned next to each other at the head positions established for this purpose. The position overlaps with the head position. Here, the magnetic head is located at two positions in order to erase one track's worth of unnecessary head positioning information group 1.

Next, the principle of erasing operation will be explained. The magnetic recording medium 16 is rotationally moving in the direction of arrow A in the figure. First, the magnetic head 2 is placed at a position on the outer circumferential side of the track 117 and slightly inside the track 117, and the magnetic head 2 is placed at a position slightly inside the track 117.
When the magnetic head 2 is in a position where it can be erased, a high-level erase command signal 10 is applied to the magnetic head 2, and the unnecessary head positioning information group 1 is mainly erased on the outermost side.
Next, the magnetic head 3 is moved inward from the position of the magnetic head 2, and a part of the unnecessary head positioning information group 1 is erased by the same operation as described above. After magnetic head 3, magnetic head 4 → same 5 → same 6 → same 7 →
The magnetic head is sequentially moved from 8 to 9, and the same erasing operation as described above is performed successively to erase all unnecessary head positioning information group 1. In addition, track 1
The part of unnecessary head positioning information group 1 on 17 is track 2 18 by magnetic heads 3 and 4.
The unnecessary head positioning information group 1 above is for magnetic head 5.
and 6, the part of unnecessary head positioning information group 1 on track 319 is
As a result, the portions of the unnecessary head positioning information group 1 on the inner circumferential side of the track 319 are respectively erased by the magnetic head 9. Note that when the magnetic head is above the necessary head positioning information group 20, a low level signal is given to the magnetic head, so the necessary head positioning information group 20 remains on the recording surface of the magnetic disk 16a. .

FIG. 3 shows magnetic disks 16a in FIG. 1a to magnetic disks 16b in FIGS. 1b and 1c,
16c is a developed view showing the state in which it is manufactured by the method explained using FIG. 2, 11 is the recorded state of one track in FIG. 1a, 12 is the recorded state of one track in FIG. 1b, Reference numeral 13 indicates the recording state of one track in FIG.
This is an erase command signal for producing No. 3. In addition,
The horizontal axis of the erase command signals 14 and 15 indicates the recording state 12,
This is the gap position of the magnetic head corresponding to position 13.

Here, in the recording state 11, 8-sector type and 12-sector type head positioning information groups 20 are mixedly recorded, and in order to obtain the desired 8-sector type or 12-sector type recording medium, it is necessary to This is achieved by the operation described in FIG. 2 by applying the erase command signal 14 or 15 for erasing the head positioning information group of other sector types except for the head positioning information group. The portions indicated by broken lines in recording states 12 and 13 indicate the erased traces of the unnecessary head positioning information group 1 erased in the head positioning information group 20 of recording state 11.

Note that positioning for erasing the magnetic head may be performed by mechanical feeding, or may be performed by applying a bias to a conventional tracking error signal. In addition, erase command signals 14 and 15
In order to obtain the reference position of the magnetic recording medium, the reference position of the magnetic recording medium may be attached to the spindle of the motor in correspondence with the reference position of the motor, and the timing may be obtained from a well-known encoder that detects the rotational position of the motor.

In the above description, the case where two types of 8-sector type and 12-sector type are mixed on the same recording medium is shown, but this can also be used when other sector types are mixed. It can also be used when two or more types of sectors are mixed. Further, although the case where the number of tracks of the magnetic recording medium is three is shown, it can also be used in cases where the number of tracks is two or four or more.

〔Effect of the invention〕

As described above, according to the present invention, a magnetic disk in which a group of head positioning information including a plurality of types of sectors is recorded on the same track is used, and an undesired group of head positioning information is stored in the magnetic head of the magnetic disk device. Since the configuration is such that erasing is performed by flowing a recording current in a fixed direction, the same magnetic disk can be easily changed to a desired sector type, and the efficiency of using the magnetic disk can be improved.

[Brief explanation of drawings]

FIG. 1 is a recording state diagram of a magnetic disk showing an embodiment of the present invention, FIG. 2 is an explanatory diagram for explaining a method of erasing unnecessary head positioning information, and FIG. 3 is a diagram showing one track of a desired sector type. Developed diagram, 4th
The figure is a recording state diagram of a magnetic disk used in a conventional magnetic disk device, and FIG. 5 is an explanatory diagram showing a conventional head positioning method. In the figure, 1 is a group of unnecessary head positioning information;
2 to 9 are magnetic heads; 10, 14, and 15 are erase command signals; 16a, 16b, and 16c are magnetic disks; 17 to 19 are tracks; and 20 is a head positioning information group. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. A magnetic disk in which the magnetic recording surface is divided into sectors by a group of head positioning information recorded radially on the magnetic recording surface, wherein the group of head positioning information is divided into sectors of a plurality of types of recording surfaces. A magnetic disk characterized in that information is recorded at a position on the magnetic recording surface corresponding to a position of a group of recorded head positioning information. 2. A magnetic head selects and erases a group of head positioning information recorded radially on a magnetic recording surface of a magnetic disk, and divides the magnetic recording surface into desired sector types using the remaining group of head positioning information. How to determine the sectors of a magnetic disk.