JPH02265077A - Hard disk device - Google Patents

Abstract

PURPOSE:To enhance the servo-resolution and to improve the access time by writing servo-information of the other face so as to be positioned between servo-information of one face of a disk. CONSTITUTION:Between servo-information HD0 by a head '0' of a first disk face, servo-information HD1 by a head '1' of the reverse side of a first disk is written. As a result, the servo-information HD0 and the servo-information HD1 are read alternately by the head '0' and the head '1', therefore, the servo information is obtained at 256 byte interval. Accordingly, at the time of seeking, a track address is obtained at 256 byte interval, and delicate servo can be executed. In such a way, the access time is quickened and the write time of the servo-information can be shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hard disk If that performs sector servo using a voice coil motor for head drive.

[Conventional technology]

Although there are various types of storage devices for computers and the like, there is a hard disk device that is characterized by its large storage capacity, quick access, and small size. This hard disk device rotates a magnetic disk, which has a magnetic recording layer formed on the surface of a hard disc made of aluminum or the like, at high speed (for example, 2,600 revolutions), and attaches a magnetic head to the surface of the magnetic disk with a minute gap. approach (e.g. 0.2-0.
Recording/playback is performed in a state where the recording/reproduction distance is 5 microns).

FIG. 2 shows an example of this type of disk device. In FIG. 2, a magnetic head 2 is disposed so as to be able to access each of the front and back surfaces of a plurality of magnetic disks 1 on which information is recorded. Each of the magnetic disks 1 is driven by a direct drive motor (Direct Drive motor).
Motor (hereinafter referred to as DD motor) 3 is used as a driving source to rotate integrally. Further, the number of magnetic heads 2 is usually twice as many as the number of magnetic disks 1, and each of these heads is integrally attached to the swing arm 4, and a voice coil motor ( Voic
e Coil Motor (hereinafter referred to as VCM) 5 allows movement in the radial direction of the magnetic disk 1.

The magnetic helads 2 are each connected to a head amplifier 6, and recording information from the drive circuit 8 is amplified and the magnetic head 2 is
The servo information etc. from is amplified.

Also provided are a servo circuit 7 that performs servo control of the VCM 5 using this servo information, and a drive circuit 8 that controls the rotation of each of the DD motor 3/VCM 5 and sends and receives signals to and from the head amplifier 6. Here, the servo circuit 7 is in a relationship to control the drive circuit 8. The drive circuit 8 is provided with a controller 9 for controlling the drive circuit 8 and for enabling transmission and reception of data from the magnetic head 2.The controller 9 is connected to an external host computer via a signal line 12. 11 are connected. The parts within the dashed line frame made up of the above-mentioned member numbers 1 to 9 constitute an enhead type (a type in which the controller is integrated with the disk device) hard disk device.

FIG. 3 is a perspective view showing details of the structure of the embedded hard disk device 1°.

As shown in FIG. 3, the magnetic heads 2 are arranged so that each pair of heads faces each other across each side of a plurality of (for example, two) magnetic disks 1, and swings outward from the magnetic disks 1. A head drive mechanism 13 that drives the arm 4 is provided. DD motor 3, swing arm 4, VCM5
The head drive mechanism 13 is attached to a base plate 14 that serves as the base of a casing that holds each member in a sealed state from the outside.

A printed circuit board (not shown) on which a motor drive circuit, a control circuit, etc. are mounted is attached to the base plate 14. The head drive mechanism 13 includes a swing arm 4, a yoke 15 that holds a magnet (not shown) and rotatably supports the swing arm 4, and a coil that is held by the swing arm 4 and movably disposed within the yoke 15. 16,
A hair ring part 17 that supports the swing arm 4, a shaft 18 that makes the hair ring part 17 rotatable and fixes it to the base plate 14, and a shaft 18 that is connected to the swing arm 4 at one end.
It is composed of a regulating arm 19 that holds the PC, and a solenoid 20 that engages the other end of the regulating arm 19 depending on the operation mode to regulate the rotation of the swing arm 4.

The casing that accommodates each of the above-mentioned members is composed of a base plate 14 and a top cover (not shown), as well as a contact area between the base plate 14 and the top cover and a VCM to maintain airtightness.
A gasket is used in the mounting portion 5, and the shaft portion of the DD motor 3 shown in FIG. 2 is filled with magnetic fluid.

Next, the operation of the hard disk device with the above configuration will be explained.

This type of disk drive device is designed to set each recording track and V in advance.
The excitation conditions of CM 5 are stored in a memory (not shown) in a controller 9 including a CPU, and
The magnetic head 2 can be positioned depending on the driving condition of the CM 5. Therefore, during operation, the drive circuit 8 selects any recording track to be recorded or reproduced in response to a command from the host computer 11. In the process of tracking this recording track, when the gap of the magnetic head 2 is located at a servo sector, a pair of servo signals formed in a staggered manner on the magnetic disk 1 are read out. The read servo signal is amplified by the head amplifier 6, and based on the servo signal output from the head amplifier 6, the drive circuit 8 controls the VCM 5 to move the magnetic head 2 in the radial direction of the magnetic disk l. .

By this control, the gap of the magnetic helad 2 is positioned on the center of the track width of the recording track. Thereafter, the VCM 5 is driven every time a servo signal is detected, and the magnetic head 2 is always positioned on the track, allowing stable data reading or writing.

Since the VCM5 has a small moving part and a simple guide mechanism, it has the advantage of being compact and low-cost to manufacture, and there is a tendency for it to be used in place of conventionally used stepping motors in the future.

By the way, since hard disks are susceptible to expansion and contraction due to heat, a sector servo method is used in which servo information is obtained for each sector and the head position is adjusted while performing detailed servo control.

For example, when each sector consists of 512 bytes, a servo information area (Sr) is provided at the beginning of each sector, as shown in FIG. This servo information area is
It consists of a track address for performing a seek and a position signal for positioning the head at the center of the track. Unlike the case where a stepping motor is used, seek management by the 70M5 is performed by track addresses, so the servo resolution is determined by the interval at which the track address arrives, that is, the time interval of 512 heights.

Further, the control shown in Japanese Patent Laid-Open Nos. 61-198470 and 62-42373 is also performed as necessary.

[Problem to be solved by the invention]

However, in the conventional sector servo method described above, resolution can only be obtained based on the time interval corresponding to the unit of data transfer with the outside (512 hides), and it is not possible to increase the resolution any further.

SUMMARY OF THE INVENTION An object of the present invention is to provide a hard disk device that can solve the problems of the prior art, improve servo resolution, and improve access time.

[Means to solve the problem]

In order to achieve the above object, the present invention writes each piece of servo information so that the servo information on one side of the hard disk is located between the pieces of servo information on the other side.

[For production]

According to the present invention, for example, when a seek is performed by head 0, the servo information of head 1 is located between the servo information of head 0, so that the number of hides is pseudo-at least half the number of bytes of the sector. Servo information can be read. That is, when one sector has a configuration of 512 bytes, servo information can be obtained at time intervals of 256 heights, making it possible to improve access time.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 is an explanatory diagram showing a servo information writing format 1- according to the present invention.

As shown in FIG. 1, the present invention is such that the servo information of one head is physically located between the servo information of another head. For example, between the servo information IHDO by head O (first disk surface glue read/write head), head l (first disk surface glue read/write head)
The servo information HDI is written on the back side of the disk surface using a read/write head).

By doing this, the servo information HDI is located between the servo information IHDO, that is, the servo information HDO
and servo information HDI are read alternately by head 0 and head 1, so that servo information HD is obtained at intervals of 256 heights.

Therefore, when seeking, track addresses are acquired at intervals of 256 heights, making it possible to perform more fine-grained servo than in the past. Moreover, since data can be transferred to the outside in units of 512 heights, compatibility with other models is maintained.

Furthermore, it is possible to write/verify the servo information of two heads in one rotation, and the writing time can be shortened.

Note that since the servo information is recorded with a shifted position, the index is set to the servo information HD01H as shown in FIG.
It may be provided so as to span the length of the recording width of the DI. By doing this, it is possible to prevent deviations in the index.

〔Effect of the invention〕

As is clear from the above, according to the present invention, each piece of servo information is written between the servo information on one side of the hard disk so that the servo information on the other side is located, thereby maintaining external compatibility. The servo resolution can be increased while maintaining the same position.

Therefore, the access time can be shortened, the writing time of servo information can be shortened, and rotation loss caused by head changes during read/write can be eliminated.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing a servo information writing format according to the present invention, FIG. 2 is a block diagram showing an example of a hard disk device, and FIG. 3 is an illustration. 1...Magnetic disk, 2...Magnetic head, 7...
Servo circuit, 8... Drive circuit, 9... Controller, 10... Hard disk device, 11... Post computer, HDI, HD2... Servo information. ■

Claims (1)

[Claims] In a hard disk drive that uses a voice coil motor using a sector servo method to seek for a magnetic head that writes and reads information to and from multiple hard disks, there is a gap between servo information on one side of the hard disk on the other side. A hard disk device characterized in that each servo information is written so that the servo information is located.