JPS63171407A - Magnetic head and its manufacture - Google Patents

Abstract

PURPOSE:To decrease erasure crosstalk and to narrow the gap for high recording density forming by forming an air gap by a notch slot to an intermediate part of the coupling face of magnetic cores coupled to each other. CONSTITUTION:A notched slot 14 is formed to the intermediate part of a face formed by bonding I-shaped cores 10a, 12a back to back. Then both ends that is, a front part 16 faced to a magnetic recording medium and a rear part 18 which is its opposite side are directly bonded and then incorporated. Coils 20, 22 are wound respectively to legs of a read/write magnetic core 10 and an erasure core 12 and a back core 24 is mounted to the rear side of the core 10. Since the air gap is formed by the notch 14 in this way, the magnetic interference between the magnetic cores 10, 12 is prevented. Then erasure crosstalk is decreased. Moreover, the gap is narrowed due to the high recording density formation.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a magnetic head having a plurality of head gaps and a method for manufacturing the same, and more particularly, to a magnetic head having a plurality of head gaps and a method for manufacturing the same. The present invention relates to a magnetic head having a structure in which a cutout groove is formed in the middle portion and only the end portions are connected and integrated without intervening a spacer material to reduce erase crosstalk, and a method for manufacturing the same.

[Prior Art] In floppy disk devices, etc., a magnetic core for read/write and a magnetic core for erase are combined to improve off-trunk characteristics and guarantee compatibility of recorded data (magnetic recording medium). When data is written to one trunk using a write gap, the write width is trimmed by an erase gap to prevent mutual interference of data between adjacent trunks. It is being

One type of magnetic head is a bulk head with a structure in which grooves and holes are formed in an integrated magnetic core and filled with non-magnetic material.
There is a type head.

In this case, there are two types: a type in which a read/write magnetic core and an erase magnetic core are directly coupled and integrated, and a type in which a non-magnetic spacer material is interposed between the two.

[Problems to be solved by the invention] In the type in which the read/write magnetic core and the erase magnetic core are directly connected and integrated without a spacer material, since both magnetic cores are in contact with the entire end surface, There is a drawback that the so-called "erase crosstalk" in which the magnetic flux picked up by the gap is transferred as noise to the read/write coil due to electromagnetic induction phenomenon increases.

On the other hand, with the type that uses a non-magnetic spacer material, both magnetic cores are separated and erase crosstalk can be reduced, but the spacer material must be prepared and assembled, which increases the number of assembly steps. However, the disadvantage is that the cost increases.

Furthermore, when the gap interval (distance between the read/write gap and the erase gap) is set to a standard value, the core becomes thinner by the thickness of the spacer material, resulting in a decrease in efficiency.

Furthermore, in recent years, with the demand for higher recording densities, the gear spacing has become narrower and narrower, making it technically difficult to construct a structure in which a spacer material is interposed.

The purpose of the present invention is to eliminate the above-mentioned drawbacks of the conventional technology, to reduce erase crosstalk, and to narrow the gap distance for high recording density, while also being easy to manufacture without increasing the number of parts. Another object of the present invention is to provide a magnetic head that is expected to have improved magnetic properties and a method for manufacturing the same.

[Means for solving the problems] The present invention, which can achieve the above objects, has the following features:
The present invention provides a magnetic head and a method for manufacturing the same, in which when two magnetic cores are combined into one, a cutout groove is formed in the joint surface to suppress magnetic interference between the two cores.

The magnetic head according to the present invention has a structure in which a read/write magnetic core and an erase magnetic core each having a head gap are coupled and integrated, and a notch groove is formed in the middle of one or both of the coupling surfaces. It has a structure in which the front part facing the magnetic recording medium and the rear part on the opposite side are directly bonded and integrated only at both ends.

Further, in the method for manufacturing a magnetic head according to the present invention, two types of bond bars, one for reading/writing and one for erasing, are created by bonding a bar made of head material and a U bar so as to form a predetermined head gap. At the same time, a notch groove is formed in the center longitudinal direction of the outer surface of the I bar of one or both bond bars, and both bond bars are separated. The bars are aligned so that they are back to back, and the bars are joined and integrated only at both end portions without interposing a spacer material, and then the bars are shredded.

[Function] In the present invention, a notch is formed on the coupling surface of one or both of the magnetic cores to be coupled, so that when the two cores are coupled, a gap is created in the coupling portion.

Therefore, since the structure is such that both magnetic cores are partially separated, the magnetic flux picked up by the erase gap is less likely to cause electromagnetic induction in the read/write coil, and therefore erase crosstalk is reduced. Furthermore, since no particular spacer material is interposed between the two, it is possible to sufficiently accommodate heads with narrow gap distances.

Also, from a manufacturing method point of view, it is only necessary to machine a notch groove in the central longitudinal direction of the bonding surface in the bond bar state.
In particular, the number of parts does not increase and assembly does not become complicated. In addition, in the present invention, since the magnetic cores are bonded only at both ends, and the bonding area is small, it is possible to suppress as much as possible distortion of the magnetic cores due to temperature changes when curing the adhesive, and as a result, the i3 magnetic It becomes possible to prevent deterioration of magnetic properties such as

[Embodiment] FIG. 1 is an explanatory diagram showing an embodiment of a magnetic head according to the present invention. This embodiment is a trunk width adjustable type magnetic head in which a read/write magnetic core 10 and an erase magnetic core 12, each having a throat gap, are coupled and integrated.

Here, the present invention is significantly different from the prior art in that notch grooves 14 are formed in the middle portions of the surfaces where the I-type cores 10a and 12a are joined back to back, and both end portions (i.e., facing the magnetic recording medium) The front part 16 and the rear part 18 on the opposite side are directly bonded (without interposing a spacer material) to form an integrated structure.

Coils 20 and 22 are wound around the legs of the read/write magnetic core 10 and the erase magnetic core 12, respectively, and the back core 2 is wound on the rear side of the read/write magnetic core.
4 is glued.

In this way, the magnetic node according to the present invention has both magnetic cores 10
．． Since a gap is formed by the notch groove 14 in the middle portion of the coupling surfaces of the magnetic cores 10 and 12, mutual magnetic interference between the two magnetic cores 10 and 12 can be prevented. In other words, even if magnetic flux is picked up by the erase gap, it is difficult for the magnetic flux to reach the read/write magnetic core 10, making it difficult to induce noise in the read/write coil. As a result, erase crosstalk can be significantly suppressed.

It is sufficient that the notch groove 14 has a very shallow depth, and it is preferable that the width be as long as possible without reducing the mechanical coupling strength between both magnetic cores.

Such a magnetic head can be efficiently manufactured by the process shown in FIG.

First, as shown in FIG. A, a bar 30 made of head material is prepared.
A binding bar 32 is prepared, and a notch 34 for adjusting the track width is formed therein with a predetermined pinch. and! The bar 30 has a cutout groove 3 in the longitudinal direction of the middle part of the outer surface thereof.
Form 6. These ■bars 30 and U-bars 32 are bonded with glass or the like to have a predetermined head gap length, and glass or the like is attached to the notch 34 formed with a predetermined pinch on the surface facing the magnetic recording medium. Fill with non-magnetic material 37.

In this way, two types of bond bars, one for write/write and one for erase, are created as shown in FIG. Here, the bond bar 38 on the left side of the drawing is for loading/writing, and the bond bar 40 on the right side of the drawing is for erasing. These have the same basic structure, but the nonmagnetic material filling portions are provided at a pitch that has an appropriate gap position and width depending on the recording track width.

After that, both bond pars 38 and 40 are bonded by aligning each gap so that the bars are back to back and bonding without interposing a spacer material, and bonding the front part 42 facing the magnetic recording medium and the opposite side thereof. The two parts of the rear part 44 are joined together using an adhesive (see FIG. 2C).

Thereafter, in order to insert the coil, the core is cut at the positions of broken wAa and broken line C to remove the rear part of the core, and the core is shredded at the position shown by broken line C to obtain a chip core. The above-described magnetic head shown in FIG. 1 is obtained by winding a coil around the thus manufactured chip core and attaching a bank core.

According to this manufacturing method, it is only necessary to add one simple cutting process of forming a notch groove on the outer surface of the bar, so it can be easily assembled without increasing the number of parts. . In addition, since both bond bars are bonded only at both ends and not fully bonded, the bonding area is reduced, and when the adhesive hardens, distortion of the magnetic core can be prevented as much as possible, and magnetic properties such as magnetic permeability deterioration can be suppressed.

Although a preferred embodiment of the present invention has been described in detail above, it goes without saying that the present invention is not limited to only such a configuration. In the above embodiment, notched grooves are formed in both the I-type core for reading/writing and for erasing, but the notched grooves are formed in only one of them, and the other can be made flat. good. By doing so, the man-hours for groove machining can be halved. Further, although grooves are formed on the side surfaces of the I-bar before joining the U-bar and the 1-bar, the grooves may be formed after they are joined to form a bond bar.

[Effects of the Invention] In the present invention, since a gap is formed by a notch groove in the middle part of the coupling surface of the magnetic cores that are coupled to each other, even if the gap interval is narrowed, there is no problem between the re-magnetic cores such as erase crosstalk. This has the effect of reducing magnetic interference, contributing to improved recording density and reduced noise, and improving the recording/reproducing performance of a recording device using this magnetic core.

Further, in the present invention, there is no need to interpose a spacer material, and the notch grooves can be formed in the long block, so the number of parts does not increase and assembly can be performed easily. Furthermore, in the present invention, both bond bars are integrally bonded only at both ends, which reduces the bonding area, minimizes the effects of distortion on the magnetic core due to curing of the adhesive and accompanying temperature changes, and improves magnetic permeability, etc. It also has the effect of preventing deterioration of the magnetic properties of the magnetic material.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing one embodiment of the magnetic head according to the present invention, and FIGS. 2A, B, and C are explanatory diagrams showing an example of the manufacturing process of the magnetic head according to the present invention. 10... Magnetic core for reading/writing, 12... Magnetic core for erasing, 14... Notch groove, 20° 22...
・Coil, 24...bank core, 30...■bar,
32...U bar, 36...Notch groove, 38...Read/write bond bar, 40...Erase bond bar. Deputy person Shigeru Minoru 2nd r.
M Su4

Claims (1)

[Claims] 1. In a magnetic head that combines and integrates a read/write magnetic core and an erase magnetic core each having a head gap, a notch groove is provided in the middle of the coupling surface of one or both magnetic cores. What is claimed is: 1. A magnetic head comprising: a front portion facing a magnetic recording medium and a rear portion opposite thereto, which are directly coupled and integrated only at both end portions. 2. Two types of bond bars, one for reading/writing and one for erasing, are created by bonding I-bars and U-bars made of head material to form a predetermined head gap, and the outside of the I-bar of one or both bond bars is bonded. A notch groove is formed in the central longitudinal direction of the side surface, and both bond bars are aligned so that the I bars are back to back, and a spacer material is interposed in the front part facing the magnetic recording medium and the rear part on the opposite side. A method for manufacturing a magnetic head, which is characterized in that the magnetic head is integrated without adhesive bonding and then shredded.