JPH02203408A - Magnetic head - Google Patents

Abstract

PURPOSE:To alloy dealing with the trend toward higher densities of recording by providing a magnetic member which comes into contact only with the 1st core of a magnetic core formed by joining the 2nd and 3rd cores via a magnetic gap for reproducing and a magnetic gap for erasing separately to both opposite side faces of the 1st core and decreases the magnetic resistance of the 1st core. CONSTITUTION:The magnetic film 23 formed to the width in the upper end part smaller than the width of the core 5 comes into contact only with the core 5 in the magnetic core. The reason for forming such film lies to prevent the electrical shorting between the cores 1 and 5 and between the cores 3 and 5 via the magnetic film 23. Since the magnetic film 23 comes in tight contact with the side face of the core 5 in such a manner, the sectional area of the magnetic path of the core 5 is correspondingly increased and the magnetic resistance of the core 5 is decreased. The magnetical saturation of the magnetic core is prevented in this way and the width size along the A direction of the core 5 is diminished. The dealing with the trend toward the higher densities of recording is thus possible.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a magnetic head for magnetically recording, reproducing, or erasing information on a magnetic recording medium, and in particular, the present invention relates to a magnetic head that magnetically records, reproduces, or erases information on a magnetic recording medium, and in particular, a magnetic head that records information separately on both opposing sides of a first core. Alternatively, a magnetic core holding device has a magnetic core formed by joining a second and third core through a magnetic gap for reproduction and a magnetic gap for erasing, and is in sliding contact with the magnetic recording medium together with the magnetic core. The present invention relates to a magnetic head to which members are joined.

[Prior Art] This type of magnetic head is used in a magnetic disk device that records and reproduces information on a magnetic disk of a magnetic recording medium, and performs so-called tunnel erasure, and has a magnetic core structure called a bulk type. The above structure is adopted. The conventional structure of this magnetic head is shown in Figure 7 (
A), (B) and as shown in FIG.

In FIG. 7(A), the numbers 1 and 3.5 are respectively front cores (hereinafter referred to as cores) that constitute the magnetic core, and the number 6 is also the back core (hereinafter referred to as core) that constitutes the magnetic core. The core 1.3 is formed into a T-shape, and the core 5.6 has a rectangular cross section and is formed into a linearly elongated rod shape. A magnetic gap for recording or reproduction (hereinafter referred to as the recording/reproducing gap) 2 and a magnetic gap for erasing (hereinafter referred to as the erasing gap) 4 are attached to the upper ends of both opposing sides of the core 5, respectively. .4
' are joined through. In this case, the erasing gap 4 is
4' are arranged to sandwich the recording/reproducing gap 2. Then, a core 6 is joined to the lower end portions of the cores 1, 3.5 joined in this way in the figure, thereby constructing a magnetic core in which two magnetic circuits are integrated. That is, cores 1 and 5.6 constitute a magnetic circuit for recording or reproduction, and core 3.5.6 constitutes an erasing magnetic circuit. Cores 5 and 6 are shared by two magnetic circuits.

In the process of assembling the magnetic head, before joining the cores 6 to the cores 1.3.5, bobbins 7.9 each having a coil 8.10 wound thereon are fitted to each of the cores 1.3.

Sliders 11.12 are bonded to both side surfaces of the cores 1, 3.5 along the A direction by adhesive. Slider 11.1
2 holds and reinforces the magnetic core made up of cores 1, 3, 5, and 6, and also slides into contact with the magnetic disk together with the magnetic core to stabilize the sliding properties of the magnetic disk. The sliders 11.12 are each formed in a block shape with grooves ttb and t2b that avoid the bobbin 7.9, and T-shaped flat joint surfaces 11c and 12c protrude from the sides facing the respective magnetic cores. It is formed.

The T-shaped horizontal surface portions of the bonding surfaces 1tc and 12c are joined to the upper ends of both side surfaces of the cores 1 and 3.5, and the central vertical surface portions are bonded to both side surfaces of the core 5. FIG. 7(B) shows a state in which they are joined in this manner.

After fitting the bobbin 7.9 to the core 1.3 from the state shown in FIG. 7(B), the core 6 is joined to the cores 1 and 3.5 to form the magnetic head body.

Furthermore, as shown in FIG. 8, the magnetic head main body 15 is fixed on an elastic plate 13, which is a support member, by gluing the slider 11 and 12 parts, and a flexible printed circuit board 14 for leading out an external circuit is connected to the elastic plate 13. , a coil 8. on the same board 14.
9 terminal 8a.

A magnetic head is constructed by connecting 8b, 10a, and 10b.

The magnetic head configured in this way has a magnetic head main body 15.
The upper surface in the figure is used as a magnetic disk sliding surface to slide on a magnetic disk (not shown) to magnetically record or reproduce information.

[Problems to be Solved by the Invention] In order to increase the recording density in the above-described magnetic head, there are two methods: increasing the recording linear density and increasing the track density. Among these methods, a method of increasing the frequency used is often adopted when increasing the linear density. In other words, if the operating frequency is doubled, the recording density can also be doubled.

However, when the recording density is doubled in this way, it is necessary to protect the data from various errors between the index field and data field formatted on the magnetic disk, such as mechanical dimensional errors and erase gate timing errors. The width of the gap field becomes 1/2.

In order to cope with this with the above magnetic head, the dimension from the recording/reproducing gap 2 to the erasing gap 4.4', that is, the width dimension along the A direction of the shared core 5 shown enlarged in FIG. It is necessary to reduce B to 1/2. In other words, in order to increase the recording density, it is necessary to make the width dimension B of the core 5 as small as possible.

However, if the width dimension B of the core 5 is made smaller, the core 5
The cross-sectional area of the core 5 becomes smaller and the magnetic resistance of the core 5 becomes higher.
As a result, the magnetic core tends to become magnetically saturated, resulting in a problem in that the recording and reproducing efficiency of the magnetic head is significantly reduced.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems in this type of magnetic head and to make it compatible with higher recording densities.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides the first
has a magnetic core configured by joining a second and third core through a magnetic gap for recording or reproduction and a magnetic gap for erasing separately on both opposing sides of the core, and A structure in which a magnetic head is joined with a magnetic core holding member that comes into sliding contact with a magnetic recording medium together with a magnetic core, including a magnetic member that contacts only the first core of the magnetic core and reduces the magnetic resistance of the first core. It was adopted.

[Function] According to such a structure, the magnetic resistance of the first core is reduced through the magnetic member, magnetic saturation of the magnetic core can be prevented, and the efficiency of the magnetic head can be improved.

[Embodiments] Details of embodiments of the present invention will be described below with reference to FIGS. 1 to 6. Here, as an example, a magnetic head for the above-mentioned magnetic disk device having a bulk type core structure will be exemplified. In Figs. 1 to 6, Fig. 7 of the conventional example (
Portions common or corresponding to those in A), (B), and FIG. 8 are given the same reference numerals, and explanations of the common portions will be omitted.

Figures 1 (A), (B) and Figure 2 explain the structure of a magnetic head according to a first embodiment of the present invention.

FIG. 1(A) is an exploded perspective view showing the structure of the magnetic head main body. As shown in the figure, this embodiment is different from the conventional example described above in that a magnetic film 23 is formed on the bonding surface 12c that is bonded to the magnetic core of the slider 12. Magnetic film 2
3 is formed by depositing a high permeability magnetic material such as permalloy by vapor deposition. The magnetic film 23 is formed on the central vertical surface portion of the bonding surface 12c, and is slightly wider than the width of the core 5 along the A direction at a position corresponding to the core 5 shared by the two magnetic circuits of the magnetic core. It is formed into a rectangular shape with a large width and a height corresponding to the core 5. However, the width of the upper end of the magnetic film 23 near the recording/reproducing gap 2 and the erasing gap 4.4' is smaller than the width of the core 5.

As shown in FIG. 1B, the sliders 11 and 12 are bonded to both sides of the magnetic core by adhesive or the like, so that the magnetic wA 23 closely contacts one side surface of the core 5 along the direction A.

In this case, as described above, the width of the upper end of the magnetic film 23 is equal to the width of the core 5.
As shown in the enlarged view around the gap in FIG. 2, the magnetic film 23 contacts only the core 5 of the magnetic cores. Of course, this is to prevent magnetic short circuit between the cores 1.5 and 3.5 through the magnetic film 23.

In addition, the code 16 in Fig. 2 is the core! , 3 and the core 5.

The structure of the other parts of the magnetic head of this embodiment is the same as that of the conventional example described above.

According to the structure of this embodiment, since the magnetic film 23 is in close contact with the side surface of the core 5, the cross-sectional area of the magnetic path of the core 5 is increased accordingly, and the magnetic resistance of the core 5 is increased. reduce Therefore, magnetic saturation of the magnetic core can be prevented, and the width dimension of the core 5 along the direction A can be reduced to accommodate higher recording density. The magnetic film 23 may be provided on the bonding surface tic side of the slider 11 in the same arrangement as above, or may be provided on both the sliders 11 and 12.

Further, as shown in FIG. 3 as an applied example, the magnetic film 23 may be formed not on the slider but on the side surface of the core 5 facing the slider. In this case, the magnetic film 23 may be provided only on the illustrated side surface of the core 5, or may be provided on the opposite side surface.

Further, technical difficulties may be considered as separate issues and may be provided on a side surface adjacent to the side surface shown in the drawing.

5m Next, FIG. 4 illustrates a structure according to a second embodiment of the present invention.

In this embodiment, instead of the magnetic llI23 of the first embodiment, '!
A magnetic plate designated by numeral 24 in Figure J4 is used. The magnetic plate 24 is made of a high permeability magnetic material, and is formed to have the same dimensions and shape as the magnetic film 11j23, except that it is thicker than the magnetic film 23.

Further, in a portion of the joint surface 12c of the slider 12 corresponding to the core 5, a recess 12d whose outer shape corresponds to that of the magnetic plate 24 and whose depth corresponds to the thickness of the magnetic plate 24 is formed.

Then, as shown by the arrow in FIG.
d and secure with adhesive.

By joining the slider 12 with the magnetic plate 24 fitted and fixed to the magnetic core, the magnetic plate 24 comes into close contact with the side surface of the core 5 of the magnetic core, and the magnetic plate 24 is brought into close contact with the side surface of the core 5 of the magnetic core. As in the case of the example, the magnetic resistance of the core 5 is reduced, and the same effect can be obtained. In this case, since the cross-sectional area of the magnetic plate 24 is larger than that of the magnetic film 23 of the first embodiment, it goes without saying that the effect of reducing magnetic resistance is greater than that of the first embodiment.

Further, FIG. 5 shows an example of application of the second embodiment.

In this case, the magnetic plate 24 is formed into a plate shape with vertical and horizontal dimensions slightly lower than the height of the core 5 and corresponding to the width of the slider 12. Further, its thickness is made slightly smaller than the width of the core 5.

Further, the recessed portion 12d is formed with a size and shape corresponding to the magnetic plate 24, and is located in a region of the slider 12 corresponding to the upper end of the core 5 and below. Form over the entire width of 2. Then, as shown by the arrow, the magnetic plate 24 is fitted into the recess 12d and fixed by adhesive.

According to such a structure, the same effect as the structure shown in FIG. 4 can be obtained, and the process of processing the recess 12d of the slider 12 and fixing the magnetic plate 24 becomes easier.

Next, FIGS. 6(A) and 6(B) illustrate a structure according to a third embodiment of the present invention.

In FIG. 6(A), the reference numeral 25 is a magnetic plate made of a high permeability magnetic material such as ferrite, and the width is 5 cores.
It is formed as an elongated rectangular thin plate that is slightly smaller than the core 5 and has a height corresponding to that of the core 5. Reference numerals 26 and 27 denote non-magnetic plates, each of which is formed as a T-shaped thin plate whose outer shape corresponds to the outer shape of the side surface facing the slider 12 of the core 1.3. The thickness thereof is assumed to be the same as that of the magnetic plate 25.

The magnetic plate 25 and non-magnetic plates 26 and 27 are integrally joined.

The integrated magnetic plate 25 and non-magnetic plates 26 and 27 are sandwiched between the core 1°3.5 and the slider 12 and fixed by adhesive, as shown in FIG. 6(B).

With such a structure, the magnetic plate 25 comes into close contact with the core 5, thereby reducing the magnetic resistance of the core 5, and the same effect as in the above-described embodiment can be obtained.

Further, in this case, a magnetic plate 25. of a shape corresponding to the magnetic core is provided on the side surface of the magnetic core consisting of the cores 1, 3.5. By joining the non-magnetic plates 26 and 27 together, there is an advantage that the mechanical strength of the magnetic core is improved.

It should be noted that something equivalent to an integrated magnetic plate 25 and non-magnetic plates 26, 27 may be provided to be sandwiched between the slider 11 and the magnetic core, or may be provided on both sides of the magnetic core.

[Effect of the invention] As is clear from the above explanation, according to the present invention, the first
has a magnetic core configured by joining a second and third core through a magnetic gap for recording or reproduction and a magnetic gap for erasing separately on both opposing sides of the core, and A structure in which a magnetic head is joined with a magnetic core holding member that comes into sliding contact with a magnetic recording medium together with a magnetic core, including a magnetic member that contacts only the first core of the magnetic core and reduces the magnetic resistance of the first core. By adopting this method, magnetic saturation of the magnetic core can be prevented by reducing the magnetic resistance of the first core, and the width dimension of the first core along the media sliding direction can be reduced to support higher recording density. You can get excellent results.

[Brief explanation of the drawing]

FIG. 1(A) is an exploded perspective view showing the structure of a magnetic head main body according to a first embodiment of the present invention, FIG. 1(B) is a perspective view of a state in which a slider is joined to a magnetic core, and FIG. 2 is the same. FIG. 3 is an enlarged view of the vicinity of the magnetic gap of the magnetic core of the head; FIG. 3 is a perspective view showing the structure of the magnetic core according to an application example of the first embodiment;
The figure is a perspective view showing the structure of the slider and magnetic plate of the magnetic head according to the second embodiment, FIG. 5 is a perspective view of the slider and magnetic plate according to an application example of the same embodiment, and FIG. FIG. 6 is an exploded perspective view showing the structure of the magnetic head main body according to an example.
B) is a perspective view of the magnetic core of the same head with a slider joined to it, FIG. 7(A) is an exploded perspective view showing the structure of the conventional magnetic head main body, and FIG. 7(B) is the magnetic core of the same head. FIG. 8 is a perspective view showing the entire conventional head, and FIG. 9 is an explanatory diagram of the core width. 1.3.5...Front core 2...Recording/reproducing gap 4.4'...Erasing gap 6...Pack core 7
．． 9...Bobbin 8.10...Coil 1
1.12...Slider 24.25...Magnetic plate 28.27...Nonmagnetic plate 23...Magnetic film

Claims (1)

[Claims] 1) A magnetic core configured by joining a second and third core to opposite sides of a first core via a magnetic gap for recording or reproduction and a magnetic gap for erasing separately. In a magnetic head, a magnetic core holding member is joined to the magnetic core, the magnetic core holding member slidingly contacting the magnetic recording medium together with the magnetic core,
A magnetic head characterized in that a magnetic member is provided that contacts only the first core of the magnetic core and reduces magnetic resistance of the first core. 2) The magnetic head according to claim 1, wherein the magnetic member is a magnetic film formed on the magnetic core joint surface of the magnetic core holding member. 3) The magnetic head according to claim 1, wherein the magnetic member is configured as a magnetic plate and is fitted into the magnetic core holding member. 4) The magnetic head according to claim 1, wherein the magnetic member is configured as a magnetic plate and is disposed so as to be sandwiched between the first core and the magnetic core holding member. 5) The magnetic head according to claim 1, wherein the magnetic member is a magnetic film formed on a side surface of the first core.