JPH0362384A - Magnetic disk device and method for detecting position of the magnetic head - Google Patents

Abstract

PURPOSE:To detect a position of a magnetic head and a position of an object track based on an address signal in a short time by forming data recording track recording an address signal and an index track recording address signals for all tracks onto a magnetic disk. CONSTITUTION:A control circuit 15 controlling a magnetic disk device employs a microcomputer, an address signal is recorded in advance onto a data recording track of magnetic disks 2, 3 before recording a data and all address signals are recorded as index to one data recording track. Every time a new data is inputted, a retrieval signal of the recording data is recorded on a column of an address signal of an object track. Thus, the position of the magnetic head and the position of the object track are detected based on the address signal in a short time by collating the address signals of all tracks recorded on the index track with the address signal read by the magnetic heads 7a - 7d.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic disk device and a method for detecting the position of its magnetic head, and more particularly to a magnetic disk device and its magnetic head configured to speed up the access operation to a target track. This invention relates to a position detection method.

2. Description of the Related Art Conventional magnetic disk drives are generally shipped as products without any data being recorded on the magnetic disk (hard disk). When a user who has purchased the magnetic disk drive connects it to a computer or the like and uses it, the magnetic disk drive is driven according to a program on the computer side, and data is magnetically recorded on each track of the magnetic disk. The control circuit of a magnetic disk device controls the cylinder, magnetic head,
A register is provided to store the address of the sector. Therefore, in a magnetic disk drive, when a command from a computer accesses using a logical sector number, the cylinder number, head number, and sector number are determined from the logical sector number to access the target track.

The magnetic head is provided, for example, at the tip of an arm driven by a stepping motor, and moves in the radial direction of the magnetic disk according to the rotation angle of the stepping motor. Then, the output shaft of the stepping motor rotates by the number of pulses output from the control circuit based on the cylinder number, head number, and sector number calculated as described above, thereby moving the magnetic head to the target track.

Problems to be Solved by the Invention In conventional magnetic disk drives, the cylinder number, magnetic head number, and sector number are calculated by the step pulse control method as described above, and then step pulses are output to cause the magnetic head to seek by the number of pulses. Therefore, there is a limit to the reduction of access time, and for example, it takes an average access time of about 8QIISeC to move the magnetic head to a target track using a stepping motor, and there is a problem that it is difficult to shorten the access time any further.

SUMMARY OF THE INVENTION An object of the present invention is to provide a magnetic disk device and a magnetic head position detection method thereof that solve the above problems.

Means for Solving the Problems (1) In the present invention, before data is recorded, an address signal is recorded in each of the data recording tracks in advance, and one data recording track has the address signals of all the tracks. It is equipped with a magnetic disk recorded for index purposes.

(2) The present invention forms, on the recording surface of a magnetic disk, a plurality of data recording tracks on which address signals are recorded in advance, and an index track on which address signals of the plurality of data recording tracks are recorded, The position of the magnetic head is detected by comparing the address signals of all the tracks recorded on the index track with the address signals read by the magnetic head.

The address signals are read from the data recording track where the working address signal is recorded and the index track where the address signals of all tracks are recorded, and the position of the magnetic head and the position of the target track are determined in a short time based on the address signals. Detection reduces access time.

Embodiment FIGS. 1 and 2 show an embodiment of a magnetic disk device and its magnetic head position detection method according to the present invention. In both figures, magnetic disk devices 1 are placed on top of each other at a predetermined interval.
It has two magnetic disks (hard disks) 2 and 3, and the two magnetic disks 2 and 3 are rotationally driven by a motor 5 (indicated by a broken line in FIG. 1) provided on the bottom surface of a chassis 4.

A carriage 6 holds four support plates 88 to 8d (only the uppermost support plate 8a is shown in FIG. 1 because they are overlapped) which support the magnetic heads 7a to 7d at their tips. Each of the support plates 8a to 8d extends substantially horizontally so that each magnetic head 7a to 7d comes into sliding contact with the edge surface above the magnetic disk 2.3.

The carriage 6 is rotatably supported on a shaft 9, and rotates counterclockwise to move the magnetic heads 78 to 7d from the outermost track io (indicated by a dashed line in FIG. 1) to the magnetic disk 2.3. Transfer to the inner circumferential side.

Reference numeral 10 denotes a stepping motor for driving the carriage, which is provided on the lower surface side of the chassis 4. An output shaft 10a of the stepping motor 10 projects toward the upper surface of the chassis 4, and a pulley 11 is fitted to the upper end of the output shaft 10a.

Reference numeral 12 denotes a steel belt, which is wound around the outer periphery of the pulley 11 in an α shape.

One end 12a of the steel belt 12 is fixed to a belt attachment member 13 fixed to the rear surface of the carriage 6.
The other end 12b is fixed to the carriage 6 by being folded back at the tip of an extension 6a extending from the carriage 6. Further, the steel belt 12 is fixed to the pulley 11 itself by spot welding.

In this way, the steel belt 12 has both ends connected to the carriage 6.
Since it is fixed to the pulley 11 at the intermediate portion and stretched so as not to loosen, it is wound around the pulley 11 or let out from the pulley 11 by the rotational drive of the stepping motor 1o. and,
The carriage 6 rotates according to the amount of winding of the steel belt 12.

That is, the magnetic heads 7a to 7d supported by the carriage 6
will be displaced according to the rotation angle of the pulley 11,
The moving distance, in other words, the magnetic recording/reproducing range is determined by the rotation angle of the pulley 11.

14 is a photointerrupter for detecting the outermost track position, and a control circuit 1 for controlling the magnetic disk device 1
5 is placed and fixed on a flexible printed circuit board 16 provided with a flexible printed circuit board 16. A detection piece 17 is formed integrally with the mounting member 13 and fixed to the carriage 6. This detection piece 17 enters into the slit 14a of the photointerrupter 14 when the carriage 6 rotates clockwise and the magnetic heads 78-7d are located on the outermost track 2A+.

Therefore, when the photointerceptor 14 is blocked from light from the light emitting element by the detection piece 17, the magnetic heads 78 to
7b is located on the outermost track 2A+.

Here, the control circuit 15 that controls the magnetic disk device having the above configuration will be explained. The control circuit 15 is a microcomputer, and various programs necessary for driving the magnetic disk device are set therein.

The control circuit 15 records an address signal on the data recording track of each magnetic disk 2, 3 before recording data, and also records an address signal for recording all the address signals on one data recording track as an index. Recording means 1
5A, magnetic head position detection means 15B for detecting the positions of the magnetic heads 78 to 7d based on the address signals, and address signal erasure prohibition means 15C for preventing erasure of the address signals recorded on the magnetic disk 2.3. It is provided.

The magnetic disk drive 1 is assembled in a factory as shown in FIG. 1, and after the assembly is completed, address signals are recorded on the tracks of the magnetic disks 2 and 3. After the magnetic disk drive 1 is assembled as described above, the control circuit 15 is supplied with power and executes the initialization mode process (shown in FIG. 3).

When the control circuit 15 is energized, first the magnetic disk 2.3
An address signal is recorded on each track (step 81).

That is, the magnetic heads 7a to 7d move on the upper and lower surfaces of the magnetic disk 2.3 to remove unnecessary magnetism, and
As shown in the figure, the upper and lower surfaces 2A of each magnetic disk 2, 3,
28.3A.

Address signals are recorded on all tracks of 3B.

In addition, in FIGS. 4(A) and 4(B), the upper surface 2 of the magnetic disk 2 is
A plurality of tracks 2A+ to 2A formed concentrically on A
Indicates T+.

In the next step S2, one track 2A out of all the tracks 2A+ to 2An on the upper surface 2A of the magnetic disk 2 is
All address signals are recorded on track 2A3, with 3 being the index track.

In this index track 2A3, as will be described later, each time new data is input, a data search signal (41 entries) is displayed in the column corresponding to the input address signal.

) is recorded, but no data is recorded in the initialization mode.

In step S3, an address signal erasure prohibition mode is set so that the address signal recorded in steps 81 and 82 cannot be erased. As a result, from now on, the magnetic disk device 1
When data is recorded, the address signal shown in FIG.
Address signals are also recorded on the lower surface 2B of the magnetic disk 2 and the upper and lower surfaces 3A and 3B of the magnetic disk 3, as shown in FIG. 4(A).

Next, with reference to FIG. 5, a description will be given of the process to be carried out when a user who has purchased the magnetic disk device 1 uses the magnetic disk device 1 by connecting it to a host computer or the like.

When the control circuit 15 is connected to a host computer or the like and energized, it first drives the motor 5 to drive the magnetic disk 2.3.
is rotated, and further the stepping motor 10 is driven to move the magnetic heads 78 to 7d. As mentioned above, before shipping the product, the index track (cylinder) 2
A3.283.

The address signal recorded in 3A3.383 is read out (step 511).

Next, an index table 18 as shown in FIG. 6 (however, FIG. 6 shows the index table on the top surface 2A of the disk 2) is created based on the address signal read in step S11 (step 512). Note that, at this stage, data signals have not yet been recorded on each track, so the search signal columns are blank except for track address 2A3.

In the next step 813, the magnetic heads 78-7d move in the radial direction, and the current positions of the magnetic heads 78-7d are detected from the read address signals of the respective tracks. Then, in the next step S14, the step 813
The address signal read out is compared with the index table 18 shown in FIG. As a result, the magnetic heads 78-7
The number of step pulses required to move d to the target track is determined, and the pulses are output to the stepping motor 10 (step 515).

Therefore, the magnetic heads 7a to 7d are connected to the stepping motor 1.
With the carriage 6 driven to 0, the magnetic disk 2.
3 upper and lower surfaces 2A, 28.3A.

Move to the target track 3B (step 816). Then, the magnetic heads 78-7d record data on the target track (step 517).

When data recording to the target track is completed, the magnetic head 78~
7d to index track 2A3゜2B3.3A3.
383 and records the search signal of the recorded data recorded in step S17 in the address signal column of the target track.

In this way, each time new data is input to the magnetic disk device 1, the processes of steps 811 to 318 described above are executed. At that time, index track 2A3.2B3.
3A3.383, a sequential search signal is recorded in the recorded address signal column, and when the magnetic heads 78 to 7d move, the magnetic heads 78 to 7d read the index track and create the index table 18 shown in FIG. Head 78~
It is possible to immediately detect which track position 7d is located. At the same time, since the moving distance to the target track to be recorded or reproduced, in other words, the number of step pulses, can be obtained, the access time can be shortened and data recording and reproduction can be processed at high speed.

As a result, in the magnetic disk device 1, conventionally approximately 8
The average access time used to be about 0 m5ec or about 6
It can be shortened to about 0 m5ec.

Although FIG. 5 shows the processing during recording, the magnetic heads 78 to 7d are driven based on the index table 18 and the address signal as described above during the reproducing operation as well.

Further, in the above embodiment, the stepping motor 10 is used to drive the magnetic heads 78 to 7d, but the present invention is not limited to this, and for example, a voice coil motor (VCM) may be used.

In the case of this voice coil motor, the seek operation is performed at a higher speed than that of a stepping motor, so the access time is shortened, but according to the present invention, when the voice coil motor is used, the average access time can be reduced to about 10 to 20 m5ec. Can be shortened. Further, in this embodiment, after the product assembly is completed, the magnetic disk device 1 is driven to record the address signal on the magnetic disk 2.3, but in addition to this, for example, before the magnetic disk 2.3 is assembled, The address signal may be recorded in advance.

Effects of the Invention As described above, according to the magnetic disk device and its magnetic head position detection method according to the present invention, the data recording track on which the address signal is recorded and the index track on which the address signals of all the tracks are recorded. Since it is formed on the magnetic disk, when moving the magnetic head to the target track, the current position of the magnetic head and the distance traveled to the target track can be immediately detected, thereby allowing the magnetic head to move to the target track at maximum speed. I can do it. Therefore, the access time required for the magnetic head to move to the target track can be further shortened than in the past, and it has the advantage of being able to handle high-speed data processing.

[Brief explanation of drawings]

FIG. 1 is a plan view of an embodiment of the magnetic disk device according to the present invention, FIG. 2 is a schematic configuration diagram of the magnetic disk device, and FIG. 3 is a diagram for explaining the processing executed by the control circuit in the initialization mode. Flowchart, FIGS. 4(A) and 4(B) are a plan view of the magnetic disk, a detailed enlarged view of the track A section on the magnetic disk, and FIG. FIG. 6 is a flowchart for explaining the processing executed by the circuit, and is a diagram showing the concept of an index table created by the control circuit. 1... Magnetic disk device, 2, 3... Magnetic disk, 2A1~2AT1.2B+~2BTl, 3A+~3
AT1.3B+~3BTl... Data recording track, 2A3.2B3.3A3.383... Index track, 7a-7d... Magnetic head, 10...
Stepping motor, 12... steel belt, 15
...1iII control circuit, 15A...address signal recording means, 15B...magnetic head position detection means, 15C...
Address signal erasure prohibition means, 18...index table.

Claims (2)

[Claims] (1) Before data is recorded, an address signal is recorded in advance on each of the data recording tracks, and one data recording track is equipped with a magnetic disk on which the address signals of all the tracks are recorded as an index. A magnetic disk device characterized by: (2) A plurality of data recording tracks on which address signals are recorded in advance and index tracks on which address signals of the plurality of data recording tracks are recorded are formed on the recording surface of the magnetic disk, and the index 1. A method for detecting a position of a magnetic head in a magnetic disk device, characterized in that the position of the magnetic head is detected by comparing the address signals of all tracks recorded in a dedicated track with the address signals read by a magnetic head.