JPH0512615A - Production of magnetic head core - Google Patents

Abstract

PURPOSE:To provide the process for production of the magnetic head core which improves the glass pooling grooves necessary for sticking the I core and C core of the laminated magnetic head core to obviate the generation of large stresses by the expansion and contraction of molding glass and does not grow cracks by cutting at the time of slicing. CONSTITUTION:Plural pieces of the glass pooling grooves 1 are provided on a core block 4 which can constitute the I core in such a manner that the glass pooling grooves 1 are provided in the core chip. The expansion and contraction of the molding glass are extremely decreased and the stresses are relieved. In addition, the glass does not receive the force from the outside at the time of slicing and, therefore, the generation of the cracks is suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an S-VHSVTR or HDTV-which uses a laminated thin film core having a high saturation magnetic flux density.
The present invention relates to a method of manufacturing a magnetic head core of a VTR, and more particularly, to improvement of a structure of a glass reservoir groove which is important for bonding an I-shaped core and a C-shaped core (hereinafter abbreviated as I core and C core).

[0002]

2. Description of the Related Art Recently, S-VHS VTR heads and HDTVs
In a so-called laminated head using a thin film core used in a VTR head, a magnetic alloy film 2 such as sendust which is a high saturation magnetic flux density material is formed on a non-magnetic substrate 3 as a core form as shown in FIG. It is made using a core block 14 obtained by depositing several layers. Then, as shown in FIG. 8, (b) glass reservoir grooves 11 are widely formed on the left and right of the magnetic alloy film 2 of the I core block 12 which can serve as an I core, and then, as shown in FIG. Is subjected to a mirror-polishing process of the butted surfaces, (b) a gap film is formed on the I core block 12 and the C core block, and after butt welding, (c) butt-finished core block 13 is obtained as shown in FIG. Further, although not described in detail, cylindrical machining,
After sliding width processing and chip slicing processing, FIG. 11 (c)
The core chip 15 was obtained.

[0003]

However, when (b) glass reservoir grooves 11 are widely formed on the left and right sides of the magnetic alloy film 2 as shown in FIG. 8, the mold glass 5 expands in the step shown in FIG. A large stress is generated due to the contraction, and (b) the I core block 12 is largely returned, so that the crack C occurs in the final mold glass 5 of the core chip 15 in (c) of FIG. Also, (c) core chip 1
Since (b) the glass reservoir groove 11 is exposed on the side surface of 5, when performing the slicing band and the side surface polishing,
The crack C is further grown by an external force such as cutting or grinding.

[0004]

In order to solve the above problems, the present invention is characterized in that a plurality of glass reservoir grooves are provided in a core block which can be an I core.

The present invention is also characterized in that a plurality of glass reservoir grooves are provided in both core blocks which can be I cores and C cores.

The present invention is further characterized in that the glass reservoir groove is provided inside the core chip without being exposed to the side surface of the core chip.

[0007]

By providing a plurality of glass reservoir grooves in the core chip as described above, the stress generated during the glass molding is dispersed, and the stress of the entire core block can be relaxed. Further, by having the glass reservoir groove inside the core chip, the glass reservoir groove is not exposed on the side surface of the core chip at the time of chip slicing due to the design of the core chip, so that only the non-magnetic substrate is sliced, and the mold glass in the core chip is You will no longer receive power from the outside. As a result, the warpage of the core chip becomes extremely small, which has the effect of making it difficult to generate cracks inside the glass of the finally obtained core chip.

[0008]

FIG. 1, FIG. 2 and FIG. 3 show an embodiment of a method of manufacturing a magnetic head core according to the present invention, and FIG. 6 shows an embodiment of the obtained core chip. First, as shown in Fig. 1,
Several (a) glass reservoir grooves 1 are processed and formed in an (a) I core block 4 in which a magnetic alloy film 2 such as sendust is laminated on a non-magnetic substrate 3. At that time, as shown in FIG. 6, the (a) is formed on the side surface of the final (a) core chip 9.
It is necessary to design for cutting so that the glass reservoir groove 1 is not exposed.

Next, as shown in FIG. 2, mold glass is molded on the upper surface, and the butted surfaces are mirror-polished.
After forming a gap film with the C core block that has already been subjected to the winding window processing, butting is performed to obtain (a) abutted core block 6 as shown in FIG. Thereafter, though not described in detail, through a cylindrical process, a sliding width process, and a chip slicing process, a (a) core chip 9 having no cracks in the mold glass 5 portion as shown in FIG. 6 is obtained.

[0010]

Embodiment 2 FIGS. 4, 5 and 7 show a second embodiment of the method of manufacturing a magnetic head core according to the present invention. In this embodiment, in addition to the machining of the (a) glass reservoir groove 1 of the (a) I core block 4 of the first embodiment, as shown in FIG.
The (a) glass reservoir groove 1 is also processed in the (a) C core block 7. Other than that, the processing steps on the way are the same, and thus the description thereof is omitted. According to this embodiment, the (b) core chip 10 having the glass reservoir groove 1 in both the I core and the C core as shown in FIG. 7 and having no crack in the mold glass portion 5 is obtained.

[0011]

As described above, according to the present invention, a plurality of glass reservoir grooves are provided only in a core block that can be an I core, or a plurality of glass reservoir grooves are provided in both core blocks that can be an I core and a C core. Since it is provided, the stress generated during the glass molding can be relieved. Further, by having the glass reservoir groove in the core chip, cracks are unlikely to occur in the glass portion when the core chip is sliced. Further, due to the synergistic effect of both the above configurations, there is an excellent effect that cracks are less likely to be generated in the mold glass portion of the completed core chip, and at the same time, the yield can be significantly improved.

[Brief description of drawings]

FIG. 1 is a perspective view of an I core block showing a first embodiment of the present invention.

FIG. 2 is a perspective view of the I core block after the glass molding.

FIG. 3 is a perspective view showing a state where the same I core block is abutted with a C core block.

FIG. 4 is a perspective view of a C core block after glass molding showing a second embodiment of the present invention.

FIG. 5 is a perspective view of the same C core block butted against the I core block.

FIG. 6 is a perspective view of a core chip obtained according to the first embodiment of the present invention.

FIG. 7 is a perspective view of a core chip obtained according to a second embodiment of the present invention.

FIG. 8 is a perspective view of an I core block showing a conventional magnetic head manufacturing method.

FIG. 9 is a perspective view of the I core block after the glass molding.

FIG. 10 is a perspective view showing a state where the I core block and the C core block are butted.

FIG. 11 is a perspective view of a core chip obtained by a conventional magnetic head manufacturing method.

FIG. 12 is a perspective view of a core block used in a conventional example and the present invention.

[Explanation of symbols]

1 (a) Glass reservoir 2 Magnetic alloy film 3 Non-magnetic substrate 4 (a) I core block 5 Mold glass 6 (a) Matched core block 7 (a) Core block 8 (b) Butted core blocks 9 (a) Core chip 10 (b) core chip

Claims (3)

[Claims] 1. A method of manufacturing a magnetic head core, which comprises forming I-shaped and C-shaped cores, which are formed by laminating soft magnetic thin films and sandwiched between non-magnetic substrates, by abutting each other. A method of manufacturing a magnetic head core, comprising providing a plurality of glass reservoir grooves on both sides of a thin film. 2. A method of manufacturing a magnetic head core, which comprises butting I-shaped and C-shaped cores in which soft magnetic thin films are laminated and sandwiched by non-magnetic substrates, and which is formed by abutting the I-shaped core side of a core chip and the C-shaped core. A method of manufacturing a magnetic head core, wherein a plurality of glass reservoir grooves are provided on both sides of both soft magnetic thin films on the core side. 3. A method of manufacturing a magnetic head core, wherein I-shaped and C-shaped cores, which are formed by laminating soft magnetic thin films and sandwiched between non-magnetic substrates, are abutted to each other, and the glass reservoir groove is not exposed on the side surface of the core chip. A method of manufacturing a magnetic head core, characterized in that it is provided inside a core chip.