JPS581802A - Magnetic recording and reproducing system and magnetic head - Google Patents

Abstract

PURPOSE:To ensure the advantagenous use for the recording of high density and at the same time to increase the sensitivity of reproduction, by recording and reproducing a kind of information in the form of plural pieces of magnetization which are parallel in the lengthwise direction and also backward to the lengthwise direction on a track. CONSTITUTION:A gap material is held between a U-shaped magnetic pole 4 and an auxiliary magnetic pole 5 to form two gaps 6 and 6'. A current is flowed to a winding coil 7 to cause a backward magnetic field, and the magnetization which is parallel and backward is obtaind at a magnetic tape 3 as shown by an arrow mark. As the self-demagnetizing function is small, the advantage is ensured for the recording or reproduction with high density. For the reproduction, an MR element 9 is set between a pair of parallel magnetic poles 8 and 8', and at the same time a gap magerial is held between an auxiliary magnetic pole 10 and the poles 8/8'. Thus two magnetic gaps 11 and 11' are formed to a reproducing magnetic head B. A contact is secured between the gaps 11/11' and the travelling tape 3 through its track part by means of the head B. The sensitivity of detection is increased since the MR element is used rationally.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic recording/reproducing system and a magnetic head, and the present invention relates to a magnetic recording/reproducing system and a magnetic head. The self-demagnetizing effect of the residual magnetization after recording on the recording medium becomes smaller, which is advantageous for high-density recording.
Another object of the present invention is to provide a magnetic recording and reproducing system and a magnetic head that have high reproducing sensitivity.

In magnetic recording, a magnetic tape with a magnetic material layer having hysteresis characteristics formed on a base such as polyester is moved over the gap of a recording magnetic head, and when a current is passed through the fill of the magnetic head, the magnetic head A magnetic field proportional to the current is generated at the gap, and the magnetic material of the magnetic tape is magnetized. After leaving the gap, residual magnetization remains on the magnetic tape as a recording signal, and magnetic reproduction is a process of recording the recording signal. When a magnetic tape is run at the same speed as when recording, it touches the gap of the magnetic head for playback.
Since there is a magnetic field on the surface of the magnetic tape, the core of the magnetic head passes through the magnetic flux, and as a result, the intersecting magnetic flux momentarily changes according to the amount of magnetization of the tape, so the core of the magnetic head passes through the magnetic flux. An electromotive force is generated by electromagnetic induction, and signals recorded on the magnetic tape are reproduced. In such a recording/reproducing system, conventionally, recording/reproducing is performed by a magnetic head in which one magnetic gap is formed corresponding to one track of the magnetic tape 1, that is, one track of the magnetic tape 1 is The magnetization of the magnetic material 1' is as indicated by the arrow in FIG. However, when there is only one line of magnetization in one track, there is a strong self-demagnetization loss, in which the residual magnetic flux of the magnetic tape decreases due to the demagnetizing field generated inside the magnetic tape, and especially when the recording wavelength The shortcoming is that the shorter the value, the greater the self-demagnetization loss, which is disadvantageous for high-density recording, and the reproduction sensitivity is correspondingly poorer during reproduction.

In addition, in magnetic recording and reproducing devices, it has been proposed to use a so-called thin film head with a high degree of integration in order to increase the density. It is difficult to
In particular, it is not possible to obtain sufficient playback detection sensitivity in a fixed head type recording/playback device where the relative speed between the magnetic tape and the head is small. Therefore, in order to solve this problem,
Recently, magnetic heads that use magnetoresistive elements (MR single elements) with high detection sensitivity in the detection section are being developed.However, conventional magnetic heads that use magnetoresistive elements are open magnetic circuits and have poor efficiency. Also, when detecting the perpendicular component of the leakage magnetic field from the recording medium magnetization, the magnetic field attenuates rapidly as it moves away from the recording medium surface, so especially in the case of short wavelengths, only the part of the element close to the recording medium is active. The kite element is made of a thin film with a thickness of several thousand amps, which causes problems in terms of abrasion, or it is difficult to make it multi-track. It has various drawbacks, such as the fact that it has a closed magnetic circuit configuration, has a large leakage magnetic flux, is inefficient, and has a complicated manufacturing process.

The present invention eliminates the above-mentioned drawbacks, and examples thereof will be described below.

FIG. 2 is an explanatory diagram of magnetization in a magnetic tape for explaining the magnetic recording and reproducing method according to the present invention, and FIG. 3 is an explanatory diagram of a recording magnetic head used in the magnetic recording and reproducing method according to the present invention. FIG. 4 is an explanatory diagram of the reproducing magnetic head.

In the figure, 3 is a magnetic tape, t is one track width which is the same as the conventional one track width, and the arrow indicates the direction of magnetization. That is, as shown in FIG. 3, for example, a gap material is sandwiched between the substantially F-shaped magnetic pole 4 and the auxiliary magnetic pole 6 to form two gaps 6 and 6' in substantially the same plane, and the wire-wound coil is In the recording magnetic head A configured as shown in FIG. 7, when a current is passed through the winding fill 7 in the direction of the arrow, magnetic fields in opposite directions are generated in the gaps 6° and 6' as shown by the arrows. When the magnetic tape 3 is running in contact with the gap 2 of the head, the magnetic tape 13 has magnetization that is antiparallel with only the opposite direction corresponding to the position of the gap 6.61, that is, parallel and opposite magnetization. is formed as shown in FIG. 2, so that one human input signal current is recorded in one track as a pair of antiparallel magnetizations in the longitudinal direction.

By recording one piece of information as a pair of antiparallel longitudinal magnetizations in this way, the self-demagnetization effect of residual magnetization on the magnetic tape becomes small, and self-demagnetization loss is reduced even in the case of high-density recording. Since it is small, it is particularly suitable for high-density recording, and is also advantageous for reproduction.

Furthermore, in order to reproduce information from a magnetic tape on which one piece of information is recorded as antiparallel magnetization with only the opposite direction as shown in Fig. 2, for example, a pair of parallel magnetizations as shown in Fig. A woven element 9 is provided between the magnetic poles 8, 8', and a gap material is sandwiched between the auxiliary magnetic pole 10 surface and the magnetic poles 8, 8' surface.
A reproducing magnetic head B having two magnetic gaps 11 and 11' formed in the same plane is used, and the magnetic gap IF, 11' portion of this magnetic head B is connected to the magnetic tape 3.
When the magnetic tape 3 is run in contact with one track portion of the magnetic head B, the magnetic flux of the magnetic tape 3 passes through the magnetic pole of the magnetic head B, and reproduction is performed. This magnetic head B has the magnetic resistance of the E1 magnetic poles 8 and 8', which is the magnetization of the magnetic tape, R,
Assuming that the magnetic resistance of the MR element is R2, the magnetic resistance of the auxiliary magnetic pole 10 is R8, and the magnetic resistance of the magnetic gap 41.11' is R4, the magnetization is as shown in Fig. 6 in terms of the equivalent circuit. Because they are arranged in series, the reproduction sensitivity is higher than that of magnetic tape, which is magnetized and recorded as shown in Figure 2.Also, since the old element does not come into direct contact with the magnetic tape, there is less wear on the MR element. There are no problems, no sliding noise is generated, there is little leakage magnetic field between magnetic poles, and MR elements with high detection sensitivity are rationally used.
In particular, it becomes possible to use a thin film head with a high degree of integration in a fixed head type magnetic tape playback device in which the relative speed between the magnetic tape and the magnetic head is small, and high density recording and playback that takes advantage of the high track density of the thin film head becomes possible. Furthermore, as shown in FIG. 6, even in multi-track reproduction of the magnetic head for reproduction as shown in FIG. 4, the kite element 9 can be formed on the substrate 12 in one step. It becomes extremely simple.

As described above, the magnetic recording and reproducing method according to the present invention is as follows.

In the in-plane longitudinal magnetization recording and reproducing method, one piece of information is recorded and reproduced in one track as a plurality of magnetizations parallel to each other in the longitudinal direction and in opposite directions.For example, when recording on a magnetic tape, etc. The self-demagnetization loss of residual magnetization afterward becomes small, which makes it excellent for high-density recording, and also provides high playback sensitivity during playback.

Further, the recording magnetic head according to the present invention has a plurality of effective magnetic gaps in substantially the same plane, and for one input signal current, the plurality of adjacent magnetic gaps have opposite directions. Since the magnetic head is configured to generate a magnetic field, when information is recorded on, for example, a magnetic tape using such a magnetic head, self-demagnetization loss due to residual magnetization after recording is small.

The reproducing magnetic head according to the present invention is excellent in high-density recording, and has a plurality of effective magnetic gaps and a magnetoresistive element in approximately the same plane, and the plurality of magnetic gaps and magnetoresistive elements are connected in series in terms of an equivalent circuit, it is possible to reproduce one piece of information recorded as multiple antiparallel magnetizations, and this reproduction Sensitivity is excellent;
It has features such as being suitable for high-density recording and reproduction.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the magnetization of a conventional magnetic tape, FIG. 2 is an explanatory diagram of the magnetization of the magnetic recording and reproducing system according to the present invention, and FIG. 3 is an explanatory diagram of the recording magnetic head according to the present invention. FIG. 4 is an explanatory diagram of a reproducing magnetic head according to the present invention, FIG. 5 is an explanatory diagram of an equivalent circuit of FIG. 4, and FIG. 6 is an explanatory diagram of a multi-track reproducing magnetic head. 3... Magnetic tape, 4... Magnetic pole, 6... Auxiliary magnetic pole, 6.6/... Gap, 7... Winding fill, A.
...Magnetic head, 8,81...Magnetic pole, 9...MR element, 10...Auxiliary magnetic pole, 11.11'...Gap, 12...Substrate. Figure 1 Figure 2 Figure 4

Claims (1)

[Claims] ■ An in-plane longitudinal magnetization recording and reproducing method, which is characterized in that one piece of information is recorded and reproduced in one track as a plurality of magnetizations parallel to each other in the longitudinal direction and in opposite directions. . ■ It is characterized by having a plurality of effective magnetic gaps in approximately the same plane, and configured so that a magnetic field in the opposite direction is generated in the plurality of adjacent magnetic gaps in response to one input signal current. magnetic head for recording. ■ A plurality of effective magnetic gaps and magnetoresistive elements are provided in approximately the same plane, and the plurality of magnetic gaps and magnetoresistive elements are connected in series in terms of an equivalent circuit. A reproducing magnetic head featuring: