JPS59193523A - Positioning method of magnetic head - Google Patents

Abstract

PURPOSE:To position a magnetic head with high accuracy by using a control disk containing a track having impulsive record patterns alternately at the inner and outer circumference sides to compare the reproduction output differences between the record/reproduction gap and an erasion gap of a magnetic head. CONSTITUTION:A magnetic head is controlled so as to set the difference absolute value ¦(V20-V21)-(V22-V23)¦ at the minimum level, i.e., zero between a reproduction output difference (V20-V21) between the record/reproduction gap and the erasion gap of an impulsive record pattern 15 of the outer circumference side and a reproduction output difference (V22-V23) between the record/reproduction gap and the erasion gap of an impulsive record pattern 16 of the inner circumference side. Thus no overlap is caused to the reproduction output for comparison, and these outputs arranged for processing. For this purpose, the fixed time interval Q between both patterns 15 and 16 is set longer than the time interval P between the record/reproduction gap and the erasion gap of a magnetic head.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for adjusting the position of a magnetic head that can be used in a floppy disk drive, which is a storage device for a computer.

Conventional configurations and their problems Recently, floppy disk drive devices have become widespread to the extent that they are used in homes, and their storage capacity has also decreased. In Otani quantification, an improvement in the radial zona 9 + - rank density of floppy disks is mentioned. The allowable amount of off-track for a rack (at a track density of 100 TPI (with 100 tracks per inch)) is approximately 40 μm. The main factors for this allowable off-track amount are the feeding accuracy of the magnetic head, the amount of expansion and contraction of the magnetic disk due to temperature and humidity, and the positioning accuracy of the magnetic head. For floppy disk drive devices, from the standpoint of compatibility, adjustment disks are commercially available for adjusting the magnetic head to a specific track position.

A conventional magnetic head position determination method will be described below with reference to the drawings. Figure 1 is a front view of the adjustment disk, where 1 is a magnetic disk, 2 is a regular track center position, and 3 is two tracks that are offset by a certain amount from the regular track, and recording is performed at a constant frequency. There is.

FIG. 2 is a front view of the magnetic head. 04 is a recording/reproducing core, and 5 is a recording/reproducing gap provided in the recording/reproducing core. 6 is an erase core, and 7 is an erase gap. FIG. 3 is a reproduction output signal waveform diagram of the adjustment disk.

The adjustment disk configured as described above and the method for adjusting the magnetic head position to I4 will be described below.

A recording/reproducing gap of the magnetic nodal in FIG. 2 is provided on the regular track center position 2 of FIG. runs, and a reproduced output signal drum-shaped as shown in FIG. 3 is obtained. Track position tlffi 8% ”z 0
It can be seen that %D matches the playback pattern. Figure 3 shows that if the recording/reproducing gap matches the regular trunk center position, the reproduction output values at B and D will be the same, but if the recording/reproducing gap shifts to the inner or outer circumference, the output values at B and D will be the same.
The playback output values are different. When fully adjusting the magnetic head using the adjustment disk, make sure that the reproduction output values of B and D are the same.

In the above (14 configuration), the position of the magnetic head is adjusted using the recording/reproducing gear knob. Tolerance ~107
1m, and problem-1 does not occur at low track density such as 48TPI, but at 100TPI to 200TPI
For high track densities such as I, a more accurate magnetic nodal position tel adjustment method is required.

OBJECTS OF THE INVENTION An object of the present invention is to provide a method for adjusting the position of a magnetic head that enables highly accurate magnetic head position adjustment.

The magnetic head position adjustment method of the present invention is based on a magnetic head position adjustment method in which all concentric track positions on a magnetic disk are aligned with the center line, and pulse-like recording patterns are provided alternately at constant time intervals on the inner and outer circumference sides. This is a method of comparing the reproduction output of the recording/reproducing gap and the reproduction output of the erasing gap, which are reproduced by a magnetic head having erasing gaps on both sides of all the recording/reproducing gaps on the trunk. This enables highly accurate magnetic head position adjustment.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 4 is a two-sided view of an adjustment disk in an embodiment of the present invention. In Figure 4, 10iJ:
The magnetic disk 11 is a track recorded at a specific position on the magnetic disk 10.

FIG. 5 shows the positional relationship of the magnetic head on the track and the adjustment pattern of the track. 12 is the centerline of a particular concentric rigid track location. 13 is the magnetic gap (recording and reproducing gap of the head, 14 is the gear notch for erasing. 15.16
are pulse-like recording patterns provided alternately at constant time intervals on the inner and outer circumference sides with respect to the center line 12 of the concentric track position.

FIG. 6 is a pattern diagram of the reproduced output when the magnetic nod runs on the track 11. 20°20', 20''
is the reproduction output (V2O) due to the recording and reproduction gap of the pulse-shaped recording pattern 15 on the outer circumference side, 21.21', 21
" is the reproduction output (v21) due to the erasure gap of the recording pattern 15, 22.22', 22N is the reproduction output (V22) due to the recording/reproduction 41 gap of the pulse-shaped recording pattern 16 on the inner circumferential side, 23.23' .

23'' is the reproducing force (V23) due to the erasing gap of the recording pattern 16.

Next, the magnetic head position adjustment method of this embodiment will be explained in detail. FIG. 6 (al is a reproducing cover turn diagram when the center of the recording/reproducing gap and the center between the erasing gap are on the center line of a specific concentric circle Is track position. Now, the pulsed recording pattern 16 on the outer circumferential side Difference in output (V2O) due to recording/reproducing gap and erasing gap
”/2+) and the reproduction output difference (
V22-v26) with an absolute difference of 7.1 value 1 (V2o
By adjusting the magnetic nod so that V2T ) (V22V2s)l becomes the minimum value, that is, zero, it becomes possible to adjust the position of the magnetic head with high accuracy: A. Fig. 6) is a cover turn diagram for reproduction when the magnetic head is misaligned (off-track) to the inner circumference side, and Fig. 6 (C1) is a cover turn diagram for reproduction when the magnetic head is misaligned (off-track) to the outer circumference side. It is a cover turn diagram for reproduction in case.

As shown in the 61st line 1, when all the playback outputs are compared and processed as described above, the playback outputs do not overlap and cannot be processed in line. is longer than the time interval P between the recording/reproducing gap and the erasing gap of the magnetic head, and is 1.5 to 2.6 in the embodiment.
It's doubled.

On the other hand, in order to improve the accuracy of the comparison process, the effective track width T of the pulsed recording patterns on the inner and outer circumference sides is made smaller than the effective track width S consisting of the recording/reproducing gear knob and the erasing gap of the magnetic head. There is.

Effects of the Invention As is clear from the above description, the present invention provides an adjustment system having tracks 71 arranged at the center line of concentric track positions on a magnetic disk, and tracks having pulsed recording patterns alternately provided on the inner and outer circumference sides. On the disk, the 1-stop output difference between the raw gap and the erase gap of the Δpil record 41 of the magnetic head is compared and processed, and the magnetic head's i'b and 'tKj are adjusted. This has the excellent effect of halving the off-track amount of the tolerance X (a<2 in the figure) with respect to the center value between the recording/reproducing gap and the erasing cap, which is a problem with the 1-4 head configuration. Ra nine. Due to this effect, it becomes possible to easily increase the track density at the current level of tolerance of the magnetic head.

Furthermore, since the relationship between the recording pattern of the adjustment disk and the magnetic head in the example is S)T,Q - (1, s ~ 2, 5) x P, the comparison process is easy and the accuracy of the reproduction output difference is increased. You can get the effect of being able to

[Brief explanation of the drawing]

FIG. 1 is a front view of a conventional adjustment disk, FIG. 2 is a front view of a magnetic head, FIG. 3 is a reproduction output signal waveform diagram of a conventional adjustment disk, and FIG. 4 is a diagram of an embodiment of the present invention. A front view of the adjustment disk, Figure 6 is a diagram of the adjustment pattern of the magnetic head and track, Figure 6+IL), (bl
, (C) is a cover turn diagram for reproduction. 1Q...Magnetic disk, 11 tracks,
12...--Specific concentric trunk position I? 13... Gap for recording/reproduction, 14... Gap for erasing, 15.16... Pulse recording pattern, 20.2
0', 20"; 22, 22', 22' --- Reproduction output of recording and reproduction gap, 21.21', 21", 2
3.23', 23"... Reproduction output of the erasure gap. Name of agent: Toshi Nakao, Phys. T., and one other person Figure 1 Figure 3 Figure 4 Figure 1

Claims (1)

[Scope of Claims] (1) An adjustment disk having trunks provided alternately at constant time intervals in a pulse-like recording pattern on the inner and outer sides of the center line of the concentric track position on the magnetic disk. By comparing the reproduction output of the recording/reproducing gap and the reproduction output of the erasing gap, which are reproduced on the track by a magnetic head having an erasing gap on both sides of the recording/reproducing gap, A method for adjusting the position of a magnetic head, characterized in that the position of the magnetic head is adjusted. (2) In the comparison process, an output difference determined by the difference between the reproduction output of the recording/reproduction gap of the pulse-like recording pattern on the inner circumference side and the reproduction output of the erasing gap and the reproduction output of the pulse-like recording pattern on the outer circumference side are determined. 2. The magnetic head position adjustment method according to claim 1, wherein the position of the magnetic head is adjusted so that the absolute value of the difference with the output difference becomes a minimum value or zero. p) The constant time interval between the pulse-like recording patterns on the inner and outer circumference sides of the adjustment disk is longer than the time interval between the recording/reproducing gap and the erasing gap of the magnetic head on the second track. A magnetic head position adjustment method according to claim (1). (4) A method of position adjusting the effective track width of the pulsed recording pattern on the inner and outer circumference sides of the adjustment disk from the recording/reproducing gap and the erasing gap of the magnetic head.