JP2000149215A - Magnetic head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic head for plural channels improved in cross talk characteristics between the channels without using a magnetic shielding plate. SOLUTION: This magnetic head 10 including plural magnetic head elements 11 mutually disposed at a prescribed interval is provided with a magnetic core 12 which is formed of a ferritic single crystal and a coil 15 which is wound around one side of the magnetic core through a winding wire window 14 formed in the magnetic core so that each magnetic head element constitutes a gap 13 at one end of a tape sliding surface side being in contact with a magnetic recording medium. An easily-magnetized axis ϕs of the magnetic core is disposed obliquely to a winding wire control axis 16 of a part onto which the coil is wound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a magnetic head for a plurality of channels used for magnetic recording and reproduction in a digital audio tape recorder (DAT) or the like.

[0002]

2. Description of the Related Art Conventionally, such a magnetic head is configured as shown in FIGS. 10 to 12, for example. FIG.
In FIG. 0 to FIG. 12, a plurality of magnetic heads 1 (in the case of FIG.
(Zero) magnetic head elements 2 and a metal base 3 for holding the magnetic head elements 2 at a predetermined interval (track pitch) from each other.

Here, as shown in FIG. 12, each magnetic head element 2 is composed of a magnetic core 4 made of, for example, a ferrite single crystal, and the magnetic core 4 has a surface (a contact surface with a magnetic recording medium). And a winding window 6 formed in the magnetic core 4 below the gap 5 in the depth direction. A coil 7 is provided outside the magnetic core 4 (right side in the figure) through the winding window 6 by winding a winding. In order to reduce the track pitch, the coil 7 is disposed on the opposite side of the winding groove 6 with respect to the adjacent magnetic head element 2, that is, sequentially with respect to the plurality of magnetic head elements 2. They are arranged alternately on the left and right.

According to the magnetic head 1 configured as described above, at the time of recording, the magnetic tape slides along the surface (tape sliding surface) of the magnetic head 1 in the direction of arrow T as shown in FIG. When the drive current IR is introduced from outside to the coil 7 wound around the magnetic core 4 of the magnetic head 1 (FIG. 13), a magnetic field corresponding to the drive current IR is generated in the coil 7. I do. The magnetic field generated in the coil 7 circulates around the winding window 6 of the magnetic core 4 as a magnetic path and passes through the gap 5,
Magnetic recording of desired data is performed on the magnetic tape.

During reproduction, a magnetic field circulating through the magnetic core 4 from the gap 5 is generated based on a magnetic signal recorded on the sliding magnetic tape, and a signal current is generated in the coil 7 based on the magnetic field. I do. Then, the signal current generated in the coil 7 is taken out to the outside and appropriately processed, whereby the data recorded on the magnetic tape is reproduced.

[0006]

By the way, in such a magnetic head 1, the magnetic core 4 generally has:
As shown in FIGS. 13 and 14, the direction of the axis of easy magnetization φs is parallel to the longitudinal axis of the portion of the magnetic core 4 where the coil 7 is to be wound (hereinafter referred to as the winding center axis). Has been established.

Accordingly, during recording and reproduction by the magnetic head 1, as shown in FIG. 14, the leakage magnetic flux φr induced by the coil 7 of one magnetic head element 2 crosses the coil 7 of the adjacent magnetic head element 2. As a result, adjacent tracks are induced as noise, and so-called crosstalk occurs due to magnetic coupling between the tracks.

Here, the magnetic head 1 is, for example, shown in FIG.
5 has a crosstalk characteristic as shown in FIG.
The crosstalk B becomes relatively large with respect to the input signal A. As a result, there is a problem that the S / N ratio is reduced, normal recording and reproduction by each magnetic head element 2 is impaired, and recording and reproduction characteristics are deteriorated. On the other hand, conventionally, as shown by a dotted line in FIG. 14, by disposing a magnetic shielding plate 8 between the magnetic head elements 2,
Leakage magnetic flux is shielded to suppress crosstalk.

In recent years, it has been required to increase the magnetic recording density by reducing the track width and the track pitch. However, when the track pitch becomes, for example, 300 μm or less, necessary components such as the magnetic core 4 and the coil 7 are required. This makes it difficult to dispose the magnetic shielding plate 8 between the magnetic head elements 2. For this reason, conventionally, in the magnetic recording / reproducing apparatus, the signal is electrically processed so as to cancel the crosstalk without using the magnetic shielding plate 8, but only the signal having the crosstalk canceling circuit is provided. In addition, there has been a problem that the configuration of the signal processing circuit becomes complicated and the cost increases.
In order to electrically perform the crosstalk cancellation, it is assumed that the crosstalk value of the magnetic head element 2 itself is constant. Therefore, the magnetic head elements 2 and the magnetic head 1 are supplied stably. There is a problem that it becomes difficult to do so.

In view of the above, it is an object of the present invention to provide a magnetic head for a plurality of channels in which the crosstalk characteristics between channels are improved without using a magnetic shielding plate. .

[0011]

According to a first aspect of the present invention, there is provided a magnetic recording medium comprising: a plurality of magnetic head elements arranged at a predetermined interval from each other; Is wound around one side of the magnetic core through a magnetic core formed of ferrite single crystal and a winding window formed in the magnetic core so as to form a gap at one end of the tape sliding surface side to be in contact with the tape. And a magnetic head in which the axis of easy magnetization of the magnetic core is arranged obliquely with respect to a winding center axis of a portion where the coil is wound.

According to the structure of the first aspect, in each magnetic head element, the axis of easy magnetization of the magnetic core is disposed obliquely with respect to the center axis of the winding, preferably at an angle of 10 to 90 degrees. Since the direction of the leakage magnetic flux induced by the coil of one magnetic head element is deviated from the direction of the easy axis of magnetization of the magnetic core, the magnetization of the magnetic core is less likely to occur, and the leakage magnetic flux is reduced. It becomes difficult to cross with the coil of the adjacent magnetic head element. For this reason, crosstalk between adjacent magnetic head elements is reduced, so that normal recording and reproduction by each magnetic head element is performed, and recording and reproduction characteristics are improved.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to FIGS. still,
Since the embodiments described below are preferred specific examples of the present invention, various technically preferred limitations are added.
The scope of the present invention is not limited to these embodiments unless otherwise specified in the following description.

FIGS. 1 and 2 show a first embodiment of a magnetic head according to the present invention. 1 and 2, a magnetic head 10 includes a plurality of magnetic head elements 11 for performing magnetic recording and reproduction for each channel, and each magnetic head element, similarly to the conventional magnetic head 1 shown in FIGS. 11 at predetermined intervals (track pitch)
, And a base (not shown) held by the base.

Here, as shown in FIG. 1, each magnetic head element 11 includes a magnetic core 12 made of, for example, a ferrite single crystal. The magnetic core 12 has a gap 13 formed so as to face each other in a region near the surface (contact surface with the magnetic recording medium), and a winding formed in the magnetic core 12 below the gap 13 in the depth direction. A line window 14 is provided. A coil 15 is provided outside the magnetic core 12 (on the right side in the drawing) through the winding window 14 by winding a winding.

Further, in the magnetic head element 11, the magnetic core 12 has a magnetization direction, that is, an easy axis φs, of which the center axis of the winding is the longitudinal axis of the portion of the magnetic core 12 around which the coil 17 is wound. It is disposed so as to extend obliquely at an inclination angle θ with respect to (indicated by a chain line in FIG. 1) 16. The inclination angle θ is preferably 10 to 90 degrees, and particularly when it is selected to be about 45 degrees, there is little adverse effect on the formation of the magnetic field required for the original signal recording by the gap 13 and the manufacturing is easy. Most preferred. In the case shown,
The direction of inclination of the easy magnetization axis φs is provided so as to extend from the region of the coil 17 toward the vicinity of the gap 13.

The inclination of the axis of easy magnetization of the magnetic core 12 is realized as follows. That is, the inclination of the axis of easy magnetization is, for example, when cutting a core block for manufacturing the magnetic core 12 from a ferrite single crystal formed in a columnar shape, cutting the core block in an inclined state corresponding to the inclination angle θ. Can be easily realized. By using the core block cut in such a manner, the magnetic head element 11 can be easily manufactured without inclining the core block by using the conventional magnetic head element manufacturing process as it is.

The magnetic head 10 according to the present embodiment is configured as described above. At the time of recording, a magnetic tape (not shown) is applied to the surface (tape sliding surface) 10 of the magnetic head 10.
a, the drive current IR is introduced into the coil 15 wound around the magnetic core 12 of the magnetic head 10 from the outside, and the drive current IR corresponding to the drive current IR is introduced. A magnetic field is generated in the coil 15. Then, the magnetic field generated in the coil 15 circulates around the winding window 14 of the magnetic core 12 as a magnetic path and passes through the gap 13 so that magnetic recording of desired data is performed on the magnetic tape. .

At the time of reproduction, a magnetic field circulating through the magnetic core 12 from the gap 13 is generated based on a magnetic signal recorded on the sliding magnetic tape, and a signal current is generated in the coil 15 based on the magnetic field. I do. Then, the signal current generated in the coil 15 is taken out to the outside and appropriately processed, whereby the data recorded on the magnetic tape is reproduced.

Here, in the magnetic head 10 described above, the easy axis φs of the magnetic core 12 of each magnetic head element 11 is inclined at an inclination angle θ with respect to the winding center axis 16. Accordingly, the direction of the leakage magnetic flux φr radiated from the coil 15 is shifted from the direction of the easy axis φs of the magnetic core 12, so that the magnetization of the magnetic core 12 is hardly generated. Thereby, the leakage magnetic flux φr of the coil 15
Are not easily crossed with the coil 15 of the adjacent magnetic head element 11, and crosstalk in the adjacent magnetic head element 11 is reduced. Thus, the recording and reproduction of the magnetic tape by each magnetic head element 11 is performed normally, and the recording and reproduction characteristics are improved.

Here, the magnetic head 10 has, for example, the crosstalk characteristic shown in FIG.
In contrast, the crosstalk B becomes relatively small. As a result, the S / N ratio is sufficiently large, and is improved by about 10 dB, for example, as compared with the crosstalk characteristic of the conventional magnetic head 1 shown in FIG.

Further, in this case, since the easy axis φs of the magnetic core 12 is inclined from the region of the coil 15 toward the vicinity of the gap 13, more magnetic flux induced by the coil 15 and passing through the gap 13 is provided. Become. Therefore, since the level of the signal A is increased by increasing the magnetic efficiency of the magnetic head element 11, the S / N ratio is further increased. Thus, the recording and reproducing characteristics of the magnetic head 10 are improved.

The magnetic head 10 is manufactured by cutting the core block from a ferrite single crystal at an angle, so that the subsequent steps are the same as those of the conventional magnetic head 1. Therefore, the burden on the production equipment of the magnetic head, that is, the additional investment is small, and the mass production is easily performed.

FIGS. 4 and 5 show a second embodiment of the magnetic head according to the present invention. In FIGS. 4 and 5, portions denoted by the same reference numerals as those of the first embodiment of the magnetic head 20 have the same configuration, and overlapping description will be omitted.
The differences will be mainly described. The magnetic head 20 differs from the magnetic head 10 shown in FIGS. 1 and 2 only in that the magnetic head element 21 includes a magnetic core 22 composed of two core halves 22a and 22b joined to each other. It has a configuration. Here, the core halves 22a, 2a
2b are each made of a ferrite single crystal, and are inclined at an inclination angle θ such that their easy axes of magnetization φs extend toward the gaps 13 as indicated by arrows in FIG.

According to the magnetic head 20 having such a configuration, at the time of recording and reproduction, magnetic recording and reproduction are performed as in the case of the magnetic head 10 described above. Here, regarding the magnetic head 20 described above, the axis of easy magnetization φs of the core halves 22 a and 22 b constituting the magnetic core 22 of each magnetic head element 21 has an inclination angle θ with respect to the winding center axis 16. It is inclined.

Accordingly, the direction of the leakage magnetic flux φr radiated from the coil 15 is shifted from the direction of the easy axis φs of the core half 22b, so that the magnetization of the core half 22b is hardly generated. This makes it difficult for the leakage magnetic flux φr of the coil 15 to intersect with the coil 15 of the adjacent magnetic head element 21, thereby reducing crosstalk in the adjacent magnetic head element 11. Thus, the recording and reproduction of the magnetic tape by each magnetic head element 11 is performed normally, and the recording and reproduction characteristics are improved.

Further, in this case, the axes of easy magnetization φs of the core halves 22 a and 22 b of the magnetic core 22 are inclined toward the vicinity of the gap 13, respectively.
The magnetic flux induced by 5 and passing through gap 13 is shown in FIG.
2 and more than the magnetic head 10 shown in FIG. Therefore, the S / N ratio is further increased.

FIGS. 6 and 7 show a third embodiment of the magnetic head according to the present invention. In FIGS. 6 and 7, portions denoted by the same reference numerals as those of the first embodiment of the magnetic head 30 have the same configuration, and redundant description is omitted.
The differences will be mainly described. The magnetic head 30 shown in FIGS. 1 and 2 differs only in that the axis of easy magnetization φs of the magnetic core 32 constituting the magnetic head element 31 is inclined in the direction of the adjacent magnetic head element 31. 10
It has a different configuration. Here, the magnetic cores 32 constituting each of the magnetic head elements 31 are each inclined at the inclination angle θ in the same direction as shown in FIG.

According to the magnetic head 30 having such a configuration, at the time of recording and reproduction, magnetic recording and reproduction are performed as in the case of the magnetic head 10 described above. Here, in the magnetic head 30 described above, in the magnetic core 32 of each magnetic head element 31, the easy axis φs is inclined at an inclination angle θ with respect to the winding center axis 16.

Accordingly, the direction of the leakage magnetic flux φr radiated from the coil 15 is shifted from the direction of the easy axis φs of the magnetic core 32, so that the magnetization of the magnetic core 32 is hardly generated. Thereby, the leakage magnetic flux φr of the coil 15
Are hardly crossed with the coil 15 of the adjacent magnetic head element 31, and crosstalk in the adjacent magnetic head element 31 is reduced. Thus, the recording and reproduction of the magnetic tape by each magnetic head element 31 is performed normally, and the recording and reproduction characteristics are improved.

FIGS. 8 and 9 show a third embodiment of the magnetic head according to the present invention. 8 and 9, the portions denoted by the same reference numerals as those of the first embodiment of the magnetic head 40 have the same configuration, and the overlapping description will be omitted.
The differences will be mainly described. In the magnetic head 40, the axis of easy magnetization φs of the magnetic core 42 constituting the magnetic head element 41 is inclined at an inclination angle θ in the direction of the adjacent magnetic head element 41, but the inclination direction is alternately reversed. The configuration is different from that of the magnetic head 30 shown in FIGS. 6 and 7 only in the orientation.

According to the magnetic head 40 having such a configuration, at the time of recording and reproduction, magnetic recording and reproduction are performed as in the case of the magnetic head 30 described above. Here, regarding the above-described magnetic head 40, in the magnetic core 42 of each magnetic head element 41, the axis of easy magnetization φs is inclined at an inclination angle θ with respect to the winding center axis 16.

Accordingly, the direction of the leakage magnetic flux φr radiated from the coil 15 is shifted from the direction of the easy axis φs of the magnetic core 42, so that the magnetization of the magnetic core 42 is hardly generated. Thereby, the leakage magnetic flux φr of the coil 15
Are not easily crossed with the coil 15 of the adjacent magnetic head element 41, and crosstalk in the adjacent magnetic head element 41 is reduced. Thus, recording and reproduction on the magnetic tape by each magnetic head element 41 are performed normally, and recording and reproduction characteristics are improved. In this case, the inclination of the axis of easy magnetization φs of the magnetic core 42 is alternately reversed with respect to the magnetic head elements 41 arranged side by side, so that the crosstalk in the adjacent magnetic head elements 41 is further reduced. Will be done.

In the embodiment described above, the magnetic core 1
The easy axes φs of 2, 22, 32 and 42 are 4
Although the inclination is 5 degrees, the inclination angle is not limited to this, and the inclination angle θ is appropriately selected within a range of, for example, 10 to 90 degrees. Then, by the easy axis φs inclined at the inclination angle θ,
Magnetization of the magnetic cores 12, 22, 32, 42 is less likely to occur, and the adjacent magnetic head elements 11, 21, 31, 41
Is reduced.

In the above-described embodiment, the axes of easy magnetization φs of the magnetic cores 12, 22, 32, 42 are respectively set in the direction of the gap or the direction of the adjacent magnetic head element with respect to the center axis of the winding. However, the present invention is not limited to this. If the easy magnetization axis φs is inclined with respect to the center axis of the winding, the crosstalk in the adjacent magnetic head elements is reduced, so that the It may be inclined.

[0036]

As described above, according to the present invention, in each magnetic head element, the axis of easy magnetization of the magnetic core is inclined with respect to the center axis of the winding, preferably by 10 to 90 degrees. Since the direction of the leakage magnetic flux induced by the coil of one magnetic head element is shifted from the direction of the easy axis of the magnetic core, the magnetization of the magnetic core is hardly generated. This makes it difficult for the leakage magnetic flux to cross the coil of the adjacent magnetic head element. For this reason, crosstalk between adjacent magnetic head elements is reduced, so that normal recording and reproduction by each magnetic head element is performed, and recording and reproduction characteristics are improved. Thus, according to the present invention, it is possible to provide a magnetic head for a plurality of channels in which crosstalk characteristics between channels are improved without using a magnetic shielding plate.

[Brief description of the drawings]

FIG. 1 is a schematic front view showing a main part of a first embodiment of a magnetic head according to the present invention.

FIG. 2 is a schematic side view showing a main part of the magnetic head of FIG. 1;

FIG. 3 is a graph showing frequency characteristics of an input signal and an output signal in the magnetic head of FIG. 1;

FIG. 4 is a schematic front view showing a main part of a second embodiment of the magnetic head according to the present invention.

FIG. 5 is a schematic side view showing a main part of the magnetic head of FIG. 4;

FIG. 6 is a schematic front view showing a main part of a third embodiment of the magnetic head according to the present invention.

FIG. 7 is a schematic side view showing a main part of the magnetic head of FIG. 6;

FIG. 8 is a schematic front view showing a main part of a fourth embodiment of the magnetic head according to the present invention.

FIG. 9 is a schematic side view showing a main part of the magnetic head of FIG. 8;

FIG. 10 is a schematic plan view showing an overall configuration of an example of a conventional magnetic head for a plurality of channels.

FIG. 11 is a schematic side view showing the magnetic head of FIG. 10;

FIG. 12 is a schematic front view showing the magnetic head of FIG. 10;

FIG. 13 is a front view of a magnetic head element constituting the magnetic head of FIG. 10;

FIG. 14 is a side view showing the magnetic head element of FIG.

15 is a graph showing frequency characteristics of an input signal and an output signal in the magnetic head of FIG.

[Explanation of symbols]

10, 20, 30, 40 ... magnetic head, 11, 12
1, 31, 41: Magnetic head element, 12, 22, 3
2, 42 ... magnetic core, 22a, 22b ... core half, 13 ... gap, 14 ... winding groove, 15 ...
Coil, 16: winding central axis, φs: easy axis of magnetization, φr: leakage magnetic flux.

Claims (7)

[Claims] 1. A magnetic head device comprising a plurality of magnetic head elements arranged at a predetermined interval from each other, wherein each magnetic head element forms a gap at one end on a tape sliding surface side to be brought into contact with a magnetic recording medium. As described above, a magnetic core formed from a ferrite single crystal, and a coil wound around one side of the magnetic core through a winding window formed in the magnetic core, the axis of easy magnetization of the magnetic core, A magnetic head which is disposed obliquely with respect to a winding center axis of a portion where a coil is wound. 2. The magnetic head according to claim 1, wherein the inclination angle of the easy axis is 10 to 90 degrees with respect to the center axis of the winding. 3. The magnetic head according to claim 2, wherein the inclination angle of the easy axis is approximately 45 degrees with respect to the center axis of the winding. 4. The magnetic head according to claim 1, wherein the direction of inclination of the easy axis is from the coil to the gap. 5. The magnetic head element according to claim 1, wherein the direction of inclination of the easy axis is directed to an adjacent magnetic head element.
3. The magnetic head according to claim 1. 6. The magnetic head element according to claim 4, wherein the direction of inclination of the axis of easy magnetization is the same.
3. The magnetic head according to claim 1. 7. The magnetic head according to claim 4, wherein the directions of inclination of the axes of easy magnetization in the respective magnetic head elements are alternately opposite directions.