JPS61194605A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To drop substantially the ratio of an error signal by approaching plural gaps used for recording and reproducing to the signal with the prescribed relative position relation ship with respect to one track of a magnetic recording medium so as to provide them and calculating an output signal from the recorded information reproducing circuit. CONSTITUTION:A ceramic substrate 2 forming plural gaps A, B and C with respect to one track is fixed on one end of a slider 1, which is supported by an elastic body. Each gap reads the signal from the specified track 20, and the signal is inputted to multiplying parts 11a and 11b comprising an arithmetic circuit 30 through a recording and reproducing circuit 26 composed of inverters 10a, 10b and 10c. The multiplied signal is added by an adding part 12, and taken out as an output. When the signals from the multiplying parts 11a and 11b are added by the adding part 12, the signal from the adding part 12 turns out to be a signal where the phase of the error signal is suppressed and errors are small.

Description

[Detailed Description of the Invention] (Industrial Application Field) What is the present invention? The present invention relates to a magnetic recording and reproducing device using a J-film head, and relates to a magnetic recording and reproducing device that suppresses error signals caused by misalignment between the track and the head.

(Prior Art) Conventionally, in the open-loop recording method of magnetic disk devices, one having one head per track has been used, and in order to prevent misalignment between the head and the track, temperature changes inside and outside the device and tracking A method has been proposed in which a state quantity related to the positional error of the upper head is detected and corrected by calculation using a microprocessor or the like.

(Problems to be Solved by the Invention) In recent years, magnetic disk drives have been required to increase their storage capacity and become smaller, but to achieve this, it is essential to increase the track density (for example, 180 per inch).
From tracks to 680 tracks per inch...In this case, the track spacing is 141 → 37μ, and the tolerance is ±
18 → ±5 μm).

However, in the above-mentioned open-loop system that detects various state quantities and performs correction, the calculation content (algorithm) that uses the state quantities as input is always the same, so the head position may vary due to aging of the device or individual differences. The error cannot be corrected, and information from adjacent tracks, which would not be a problem with conventional track density, is picked up, causing read errors.

FIGS. 4(a) and 4(b) show the relationship between the track and the gap and the waveform of the output signal when recording and reproducing are performed with one gap on such one track.

In FIG. 4(a''), it is assumed that the truck is moving in the direction of arrow F. 20 is the designated truck (
Recorded information is written in position b). 21 is an adjacent track, shifted by (C) from position (A) (mouth)
Recording information is written at the location. Reference numeral 22 denotes a head having one gap 23, and the head 22 is shifted in the direction of arrow G so that part of the gap 23 reproduces information even on the adjacent track 21. In this case, the output signal from the gap 23 has a peak value as shown in FIG. 4(b), and the original data is reproduced in a phase-shifted form, causing an error.

Means for Solving the Problems> The present invention has been made in view of the above-mentioned drawbacks of the prior art.
The purpose of this system is to significantly reduce the ratio of error signals even if there is a shift similar to that of conventional methods, and its structural feature is that signals are recorded and reproduced on one track of a magnetic recording medium. A plurality of gaps are provided adjacent to each other with a predetermined relative positional relationship, and the apparatus is equipped with a recorded information reproducing circuit corresponding to each gap and an arithmetic circuit for calculating an output signal from the recorded information reproducing circuit. be.

Effect> When the recorded information of a track adjacent to the gap on the side of the plurality of gaps is reproduced, the reproduced signal is multiplied by the signal of the gap on the original track side, and the information on the gap on the original track side is multiplied by Signals from two or more gaps are multiplied and these values are added to reduce the proportion of error signals due to positional deviation compared to signals from gaps on the original track side.

<Example> Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1(a) and 1(b) show an embodiment of the present invention, in which (a) is a perspective view of a thin film head, and FIG. 1(b) is a block diagram showing the relationship between the gap and the signal processing circuit. In FIG. 1(a), reference numeral 1 denotes a slider made of, for example, a ferrite core, and a ceramic substrate 2 having a plurality of gaps A, B, and C formed for each track is fixed to one end of this slider. This slider is supported by an elastic body and is moved to a designated track 20 as shown in FIG.
Each gap reads a signal, and inputs it to the multipliers 11a and 11b that constitute the arithmetic circuit 30 via the recording/reproducing circuit 26 consisting of inverters 10a, 10b, and 10c, and the multiplied signals are added by the adder 12. and retrieved as output.

Signal processing in such a device will be explained.

Figures 2 (a) and (b) show the signal state when slider 1 (head) is slightly shifted upward from the track of the disk moving in the direction of arrow X, and the gap between The recorded information on the track 21 to be recorded is picked up at the position (a), and the recorded information on the original track 20 is picked up at the position (b) with the gap between B and C. In this embodiment, the pickup signal from the gap A and the pickup signal from the gap 8 are multiplied by the multiplier 11a shown in FIG.
As shown in Figure (b), the peak value becomes smaller. Next, the multiplier 11b multiplies the pickup signals from gaps 8 and C.
When multiplied by , the phase relationship is strong, so the peak value increases as shown in FIG. 2(C). These multipliers 11a
When the signals from 11b and 11b are added in the adder 12, the phase of the error signal in the signal from the adder 12 is suppressed, and the original information from the track 20 is emphasized, as shown in FIG.
) The waveform becomes as shown in the figure, and the error is smaller than that of the conventional example (see FIG. 4(b)).

FIG. 3 shows another embodiment. In this embodiment, the outputs from the multipliers 11a and 11b shown in FIG. Part 2
Actuator 2 whose head is fixed according to the output of 7.
If the winding current of 8 is corrected, it can be used as position information as is.

Although the present embodiment has been described using three gaps, the same effect can be obtained even if three or more gaps are provided.

(Effects of the Invention) As described above in detail with the embodiments, according to the present invention, even if the tracks become denser and the head position picks up recorded information on other tracks as error information, the error Since information can be suppressed and detected, and the output signal from each gap can be calculated and used as position information, high density can be achieved with a simple circuit.

[Brief explanation of drawings]

Figure 1 <a) (b) shows one embodiment of the present invention, (a) shows iii#lI head no strabismus, and (b) shows an embodiment of the present invention.
A block diagram showing the relationship between the Lt gap and the signal processing circuit,
FIGS. 2(a) to (d) are explanatory diagrams showing the state in which the head is off the track and the state of the output signal in the present invention, FIG. 3 is an explanatory diagram showing another embodiment, and FIG. 4 is an explanatory diagram showing the state of the output signal in the present invention. FIG. 6 is an explanatory diagram showing a state in which the head is deviated from the track and a state of an output signal in an example. 1...Slider, 2...Ceramic board, 20...
- Designated track, 26... Recorded information reproducing circuit, 30.
...Arithmetic circuit, A, B, C... gap. Figure 1 (a) (b) Figure 2 td>,

Claims (1)

[Claims] A plurality of gaps for recording and reproducing information are provided adjacent to one track of a magnetic recording medium with a predetermined relative positional relationship, and a recorded information reproducing circuit corresponding to each gap and this recorded information reproducing circuit are provided. A magnetic recording/reproducing device characterized by comprising an arithmetic circuit that calculates an output signal from the circuit.