JPH0746405B2 - Disk drive device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a disk drive that moves a head on a disk of a recording medium to record and erase information on the disk with a predetermined track width and a predetermined track pitch. It relates to the device.

[Prior Art] As a disk drive device of this type, there is a magnetic disk drive device. That is, in this device, the magnetic disk is rotationally driven, and the magnetic head is moved along the radial direction of the magnetic disk on the magnetic disk to record, reproduce or erase information on the magnetic disk with a predetermined track width and a predetermined track pitch. I am doing it.

In recent years, in a magnetic disk drive device, a configuration has been developed in which magnetic head positioning control is performed via servo signals for magnetic head positioning control recorded on both sides of a track of a magnetic disk. This is because the magnetic head positioning control is performed with high accuracy in accordance with higher recording density.
The servo signal is written on the magnetic disk after erasing all the recorded information on the magnetic disk before formatting the magnetic disk. This writing is conventionally performed using a dedicated writing device.

[Problems to be Solved by the Invention] However, in the case of considering a configuration in which the above-described servo signal writing is performed by the magnetic disk drive device itself without using a dedicated device, the writing itself has no problem, but before that There are the following problems with erasing.

That is, in the magnetic disk drive device which controls the head positioning by the servo signal, the tunnel erasing method is not usually adopted in order to increase the recording density, and the track width is narrower than the track pitch. For this reason, even if the data is erased at a regular track pitch, a portion of the magnetic disk that cannot be erased remains. If the unerased portion remains, this may cause deterioration of the servo signal and the recording data to be written later.

[Means for Solving the Problems] In order to solve the above problems, according to the present invention, a head is moved on a disk to record information on the disk at a predetermined track width and a predetermined track pitch, Or in a disc drive device that reproduces recorded information,
Erasing means for supplying an erasing current to the head to erase information recorded on a track on the disk; and moving the head with respect to the track on the disk with a predetermined feed width smaller than the track width. Head moving means and a servo signal writing means for writing a servo signal for positioning control of the head for each track in the area between the tracks on the disk by the head, and prior to the writing operation of the servo signal writing means. ,
The head moving means is operated to move the head on the disk with the predetermined feed width, and the erasing means is operated to sequentially erase the information recorded on the disk, and the erasing is completed. The servo signal writing means controls the servo signal writing means to write the servo signal in the area between the tracks.

[Operation] According to this structure, the information recorded on the disk is first erased before the start of the servo signal writing operation, and the head is moved with a feed width smaller than the track width during the erasing. By erasing the data, all the recorded information can be completely erased without being erased, and then a new servo signal can be written.

[Examples] Hereinafter, details of examples of the present invention will be described with reference to the accompanying drawings.

First Embodiment FIG. 1 is a block diagram schematically showing the configuration of one embodiment of a magnetic disk drive device adopting the present invention.

In FIG. 1, reference numeral 1 is a control unit for controlling the entire apparatus, which is composed of a microcomputer.

The magnetic head 3 is connected to the control unit 1 via a read / write circuit 2 that amplifies a read signal from a magnetic disk (not shown), demodulates the read data, modulates write data, and amplifies an erase signal. Has been done.

Further, the control unit 1 includes a disk drive motor 4 which is a drive source of a disk drive mechanism for rotationally driving the magnetic disk, and a stepping motor 5 which is a drive source of a head seek mechanism for moving the magnetic head 3 in the radial direction of the magnetic disk. , And a head load solenoid 6 which is a drive source of a head load mechanism for loading the magnetic head 3 onto the magnetic disk are connected via a driver (not shown).

Further, the control unit 1 has the outermost track 00 of the magnetic disk.
A sensor group such as a track 00 detection switch 7 for detecting the position of the magnetic disk, an index detector 8 for detecting an index hole of the magnetic disk, and a write protector sensor 9 for detecting whether or not the magnetic disk is write-protected are connected. There is.

Under such a configuration, the control unit 1 refers to the output of the sensor group in accordance with a command and data input from a computer of a host system (not shown),
The drive of the stepping motor 5 and the head load solenoid 6 is controlled to cause the magnetic head 3 to write, read, or erase data in the magnetic disk via the read / write circuit 2.

By the way, in addition to such a conventional configuration, in the present embodiment, a host system (not shown) can be configured to instruct the control unit 1 to write the servo signal for the magnetic head positioning control described above. When receiving this command, the control unit 1 erases all the recorded information on the magnetic disk and then writes the servo signal.
The details of the operation during this period will be described below. Incidentally, the positioning of the magnetic head in the control at the time of erasing at this time is performed by a counter provided in the control unit 1 for counting the ordinal number of the track.
It is done according to the count of 10. The counter 10 is provided as hardware or is realized by software.

The operation at the time of writing the servo signal is performed as follows according to the control procedure of the control unit 1 shown in FIG.

That is, when the controller 1 receives the servo signal write command, it executes the routine shown in FIG. 2 and first clears the count N of the counter 10 to 0 in step S1.

Next, in step S2, the magnetic head 3 is moved to the N-0.5 track, that is, -0.5 track in the first case, outside the outermost track 00 by a half track pitch (in the outer peripheral direction of the disk).
Position to.

Next, in step S3, one round (or a plurality of rounds) is erased at the position determined in step S2.

Then, in step S4, it is checked whether or not the count N has reached the count Nmax + 1 obtained by adding 1 to the ordinal number of the innermost track.

If it is not Nmax + 1, the magnetic head 3 is obtained in step S5.
To N tracks. That is, in the first half track pitch inside (inner circumferential direction of the disk) from the position at the time of erasing in step S3, the track is moved to track 00.

Subsequently, after another erasure (or several laps) is performed in step S6, the counter 10 is incremented in step S7, and then the process returns to step S2 to repeat the loop of steps S2 to S7.

By repeating this, the magnetic head 3 is sequentially moved in the inner circumferential direction of the disk by a half track pitch to erase one round (or several rounds).

Then, erasing is completed up to a position within a half track pitch from the innermost track, and step S4 of the loop of steps S2 to S7.
At N = Nmax + 1, the process branches to step S8, a servo signal writing routine is performed, and the control is ended. Although the servo signals are written in the areas on both sides of each track, the description of the writing operation itself will be omitted.

As described above, according to this embodiment, before writing the servo signal, the magnetic head is moved by half a pitch from a position outside the outermost track 00 by a half track pitch to a position inside the innermost track by a half track pitch. Is erased.
Normally, the track width of the magnetic head is 2/3 of one track pitch.
Wider than half track pitch. Therefore, in erasing sequentially performed once or several times, erasing is performed such that the outer edge portion of each erased area overlaps the inner edge portion of the outer erased area performed immediately before, and between the erased areas. No gap is created and no unerased area is created.

That is, according to this embodiment, the servo signal is written after the erasure is completely performed without erasure.
It is possible to reliably prevent the deterioration of the servo signal and the subsequent recording data caused by the unerased portion.

Second Embodiment By the way, the method of erasing and writing the servo signal by the configuration of FIG. 1 is not limited to the one described above,
As an example, it is also possible to carry out as follows by the control procedure of the control unit 1 as shown in FIG.

That is, the count N of the counter 10 is cleared to 0 in the first step S21.

Next, in step S22, the magnetic head 3 is moved to N tracks,
That is, in the first case, position it on the outermost track 00,
At that position, one cycle (or several cycles) is erased in step S23.

Next, in step S24, it is checked whether or not N has reached the above-mentioned Nmax, and if not, the counter 10 is incremented in step S25, the process returns to step S22, and steps S22 to S25.
Is repeated as a loop.

As a result, the magnetic head 3 is sequentially moved by one track pitch from the outermost track 00 to the innermost track,
Erasing is performed once (or several times) at each track position.

Then, the erasing of the innermost track is completed and N
= Nmax, the process proceeds to step S26. At this point, as described above, the track width is about 2/3 of one track pitch, so that an unerased area remains between the erased areas of adjacent tracks.

In step S26, −0.5 is set in the counter 10.

Next, in step S27, the magnetic head is moved to N tracks. That is, in the first case, the track is positioned 0.5 track outside the outermost track 00 and positioned outside the half track pitch.

Then, in step S28, one round (or several rounds) of data is erased at that position, and then a servo signal is written in step S29. That is, in the first case, the servo signal is written in the area of track -0.5.

Next, in step S30, it is checked whether or not the count N has become Nmax + 0.5. If not, in step S31 the counter 1
Increment 0, return to step S27, step S2
Repeat 7 to S31 as a loop.

By repeating this, the unerased areas between the tracks are sequentially erased from the outer peripheral side, and the servo signals are sequentially written in the areas.

Then, after the writing of the servo signal to the area inside the half track from the innermost track is completed, N = Nmax + in step S30.
When it reaches 0.5, control ends.

As described above, according to the method of erasing each track first, and then writing the servo signal while sequentially erasing the areas on both sides of each track (areas between the tracks), as compared with the case of the first embodiment. Although the order is different, the result is the same, and the servo signal can be written by erasing the information previously recorded on the magnetic disk without erasing all the information.

Third Embodiment As a further different erasing method before writing a servo signal, the magnetic head is continuously erased from the outer half track outside of the outermost track 00 to the inner half track of the innermost track without erasing. And the amount of movement in that case is set to be smaller than the track width for one rotation of the magnetic disk.

In this case, the locus of the magnetic head on the magnetic disk becomes spiral, and the track pitch P of each erase track S is smaller than the track width T and is adjacent to each other as shown in the enlarged view of the area A of the magnetic disk 11 in FIG. Since both side edge portions of the matching erase tracks S overlap each other, it is possible to completely erase without erasing.

The above technique is not limited to the magnetic disk drive device, but can be similarly applied to other disk drive devices such as an optical disk drive device when the above-described servo signal writing is considered.

[Effect] As is apparent from the above description, according to the present invention, the head is moved on the disk to record information on the disk with a predetermined track width and a predetermined track pitch, or reproduce the recorded information. In the disk drive device to
Erasing means for supplying an erasing current to the head to erase information recorded on a track on the disk; and moving the head with respect to the track on the disk with a predetermined feed width smaller than the track width. Head moving means and a servo signal writing means for writing a servo signal for positioning control of the head for each track in the area between the tracks on the disk by the head, and prior to the writing operation of the servo signal writing means. ,
The head moving means is operated to move the head on the disk with the predetermined feed width, and the erasing means is operated to sequentially erase the information recorded on the disk, and the erasing is completed. Since the structure provided with the control means for controlling the servo signal to be written by the servo signal writing means in the area between each track, the servo is performed after completely erasing the recorded information on the disk without erasing it. It is possible to write a signal, and it is possible to obtain the excellent effect that the problem due to the existence of the unerased residue is avoided and the reliability of the device is improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a magnetic disk drive device according to a first embodiment of the present invention, FIG. 2 is a flow chart showing a control procedure at the time of writing a servo signal by a control unit in FIG. 1, and FIG. FIG. 4 is a flow chart of a control procedure at the time of writing a servo signal according to the second embodiment, and FIG. 4 is an explanatory diagram of an erased state before writing a servo signal according to the third embodiment. 1 ... Control unit, 2 ... Read / write circuit 3 ... Magnetic head, 4 ... Disk drive motor 5 ... Stepping motor 6 ... Head load solenoid 7 ... Track 00 detection switch 8 ... Index detector 9 ...... Write protect sensor 10 …… Counter

Claims (1)

[Claims] 1. A disk drive apparatus for moving information on a disk to record information on the disk with a predetermined track width and a predetermined track pitch, or to reproduce the recorded information, wherein an erase current is applied to the head. An erasing means for supplying and erasing the information recorded on the track on the disk; a head moving means for moving the head with respect to the track on the disk with a predetermined feed width smaller than the track width; Servo signal writing means for writing, by the head, a servo signal for positioning control of the head with respect to each track in an area between the tracks on the disk, and the head moving means for moving the head signal before the writing operation of the servo signal writing means. The head is moved to move on the disk with the predetermined feed width, and Control means for operating the recording / erasing means to sequentially erase the information recorded on the disk, and controlling the servo signal writing means to write the servo signal in the area between the tracks where the erasing is completed. And a disk drive device.