JPH0341605A - Magnetic head core and production thereof - Google Patents

Abstract

PURPOSE:To improve magnetic characteristics and the adhesive strength of a core block by disposing gap plates formed to a prescribed gap size and brazing material foil between the cores of a pair of magnetic metals and melting the brazing material foil, thereby coupling the two cores. CONSTITUTION:The gap plate 1 consisting of the nonmagnetic material formed to the prescribed gap length size is disposed at a center. The silver brazing material foil 2 are disposed on both sides thereof and further, magnetic metal blocks 3 are disposed on both sides thereof. Further, the silver brazing material foil 2 and the gap plates 1 are successively arranged in this order in multilayered form on the outer side of the magnetic metal blocks 3 and the assembly is subjected to a thermopressurizing treatment at the temp. at which the silver brazing material foil 2 melts in a vacuum or nitrogen atmosphere. The size of the gap length is formed of the gap plate in this way and, therefore, the gap length is accurately formed and since the two cores are bonded by melting the silver brazing material foil, the wettability of the magnetic metal blocks is enhanced and the adhesive strength is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a magnetic head core suitable for a magnetic card head and its 1tJTih method.

(Prior art) Magnetic heads applied to VTRs, audio equipment, etc.
The magnetic core is made of ferrite made of magnetic oxide, and this magnetic core is bonded to glass or the like.

However, since the magnetic card, which has been widely mentioned in recent years, is a medium with a high saturation magnetic flux density, magnetic heads applied to VTRs, audio, etc. have a low magnetic saturation magnetic flux and cannot record sufficiently on the magnetic card.

Under these circumstances, it has become necessary to develop a magnetic head whose magnetic core is made of a magnetic metal with a high saturation magnetic flux density, as a magnetic head suitable for magnetic cards. Therefore, since it is difficult for metal and glass to adhere inside the shell, the applicant has developed a magnetic head for magnetic cards that uses a thin silver brazing material suitable for bonding magnetic metals together. I came.

As shown in FIG. 7, this magnetic head consists of a pair of core blocks 2 made of a magnetic metal that are butted together through a silver solder t[27] with a thickness of approximately 30μ forming a gap.
A back core 25 made of a magnetic material such as a magnetic metal permanent [1a] is joined to a front core 24 made of 1.22, and a coil 26 is wound around the back core 25.

In order to manufacture such a magnetic head in YJ construction, first, the front core 24 is subjected to tJ2i, and then the back core 25 is joined thereto.

FIG. 8 shows a method of manufacturing the front core 24, in which a pair of core blocks 21, 22 and a thin silver brazing material 27 are prepared, and a jig is used to arrange the core blocks 21, 22 and silver brazing material 11127 in a predetermined relationship. Place the silver solder thin 2
Heat treatment is performed at a temperature of 650 to 700° C. at which No. 7 is not melted and bonded.

The reason why the temperature was set so that the silver soldering material 27 would not melt during the heat treatment is that when the silver brazing material λ927 is melted and bonded, the thickness of the silver soldering material 27 is as thick as 30μ!
The thickness of the ten pieces 1127 changes due to melting, making it impossible to form the gap length dimension with high accuracy. This is also due to drawbacks such as the generation of air bubbles in the gap.

<Problems to be Solved by the Invention> However, the above-mentioned magnetic head core is made by heat-treating a pair of core blocks 21 and 22 made of magnetic metal at a temperature at which the thin material 27 does not melt and becomes viscous. There were problems in that the bonding strength was weak, and the thin silver brazing material diffused into the magnetic metal, making it impossible to form the gap length with high precision.

The present application was made in order to solve the above-mentioned problems, and aims to prevent the diffusion of thin silver brazing material into the magnetic metal, shape the gap length with high precision, and improve the magnetic properties.
An object of the present invention is to provide a magnetic head core with improved adhesion (bonding) strength of core blocks.

(Means for Solving the Problems) In order to achieve the above object, the magnetic head core of the present invention includes a gap plate formed with a predetermined gap size between a pair of cores made of magnetic metal, and a gap plate formed on both sides of the gap plate. The core is characterized in that the two cores are joined by melting the brazing material and melting the brazing material. In addition, the manufacturing method of the magnetic head core is to place one IB material on both sides of a gap plate formed with a predetermined gap length, and further arrange magnetic metal blocks on both sides, and melt a silver D-shaped material. A process of forming a block in which a gap plate, a thin material, and a magnetic metal block are integrated by heat processing at high temperature, and cutting one block in a direction perpendicular to the above arrangement direction to form a large number of cores. It consists of a step of separating into blocks, a step of forming a gap groove in the core block, a step of cutting the core block in the arrangement direction to form individual front cores, and a step of joining the back core to the front core. It is characterized by

<Function> Since wax is placed on both sides of the gap plate and the wax is melted to join both cores, the gap length can be formed with high accuracy because the gap length is formed by the gap plate. At the same time, the material is as thin as 1 to 2 μm, so no air bubbles are generated. Also, rd thin wax material! ! ! Since both cores are bonded together, the wettability of the magnetic metal block is improved and the adhesive strength is improved.

Furthermore, the manufacturing method of the magnetic head core is such that a magnetic metal block, a brazing material filler, and a gap plate are formed into a block by heat and pressure treatment, and by cutting this block, a large number of core blocks can be formed, reducing the number of processing steps. can.

(Embodiment) FIGS. 1 to 5 are perspective views showing the manufacturing process of a magnetic head core according to an embodiment of the present invention. The steps will be explained below in order.

First, as shown in FIG. 1, a gap plate 1 made of J1!1 material such as copper, titanium, or silver is placed in the center with a predetermined diameter.

A silver solder plate 2, which is a brazing material, is placed on both sides, and a magnetic metal block 3 is placed on both sides thereof.

still,! ! Since the plate thickness of the brazing material sheet 2 is as thin as 1 to 2 μm, it melts and partially flows when melted, so it can be ignored in terms of gap length.

Outside the magnetic metal block 3, a silver brazing material 12 and a gap plate 1 are further arranged in a multi-layered manner with the magnetic metal block 3 in common.

These are stacked together and silver [
At a temperature of 750°C to 850°C where 1 material thin 2 melts 2 to 850°C
Heat and pressure treatment is performed for 3 hours. When the product thus formed was used for 11 days, no diffusion of silver solder occurred on the bonding surface. The reason for this is presumed to be that a eutectic reaction occurs when the thin silver solder material diffused during heating melts and is pulled into the silver solder.

Then, the silver brazing material M2 is bonded at the contact portion with the 11 bamboo metal block 3, and as shown in FIG. 2, a multi-body block 4 is formed which is integrated as a whole. Thereafter, the core blocks 5 are cut in a manner perpendicular to the arrangement direction as shown by the dotted line L1 to form a large number of core blocks 5 as shown in FIG.

Next, as shown in FIG. 4, a gap groove 6 including the gap 1a is formed by machining such as cutting.

Then, it is cut in a direction perpendicular to the arrangement direction as indicated by dotted line L2, and further in the arrangement direction as indicated by dotted line L3. As a result, a large number of individual front cores 7 as shown in FIG. 5 are formed.

A back core is joined to the front core 7 manufactured as described above to obtain a magnetic head core as shown in FIG. 7.

The configuration of such a magnetic head and 1! With the J manufacturing method, even when manufacturing a multilayer magnetic head core with a more complicated structure than usual, each layer constituting the head core is sequentially laminated in advance and heated and pressurized at a temperature where the silver brazing material 'a2 melts. , a block with these layers integrated is formed at once.

A large number of front cores 7 can be manufactured by cutting this block, for example, three times, thereby greatly reducing the number of man-hours.

Since the block is cut, a highly reliable magnetic head core can be provided without gap or core misalignment.

In the above embodiment, the core (eleven metal block) 3.
The heat and pressure treatment is performed by placing silver brazing material i#2.2 on both sides of the gap plate 1 and the gap plate 1 between the gap plate 1 and the gap plate 1, as shown in FIG. 6. It is also possible to use one that has been previously clad with silver, or one that has been subjected to sputtering or vapor deposition.

Furthermore, although silver brazing material is used as the brazing material, it is not limited to silver brazing material, and the same effect can be obtained by using aluminum copper material, baladium copper material, or gold brazing material.

(Effects of the Invention) As described above, since the magnetic head core of the present application is formed with the gap plate 1, the gap length is determined by the gap plate 1, so the gap length can be formed with high precision, and the brazing material Since the thickness is as thin as 1 to 2 μm, no air bubbles are generated and the magnetic properties are improved.

Furthermore, since the two cores are bonded by melting the thin brazing material, the wettability of the magnetic metal block 3 is improved, and the adhesive strength is improved two to three times compared to the conventional method.

Furthermore, the manufacturing method of the magnetic head core is improved by forming a block 4 in which a magnetic metal block 3, a gap plate 1, and a thin brazing material are integrated by heat-pressing T8 process, and cutting this block 4 to form a large number of core blocks. 5 can be obtained, which has the effect of reducing manufacturing costs by manufacturing in large quantities.

[Brief explanation of drawings]

1 to 5 are perspective views showing each manufacturing process of a magnetic head core according to an embodiment of the present invention, FIG. 6 is a partial perspective view showing another *embodiment, and FIG. 7 is for explaining the magnetic head core. FIG. 8 is a perspective view showing a conventional example. DESCRIPTION OF SYMBOLS 1... Gap plate, 2... Silver 0 thin, 3... Magnetic metal block, 4... Multilayer block, 5... Core block, 6... Gap groove, 7... front core. 1. Figure 3. Fe-Al-5iA &> 7o-, F Figure Figure Figure Figure Figure Figure Procedure Amendment (Spontaneous) 1. Indication of the incident Patent Application No. 1-177782 2. Invention Name of magnetic head core and its manufacturing method 3, Relationship with the case of the person making the amendment Patent applicant address 1-7 Yukitani Otsuka-cho, Ota-ku, Tokyo 145 Name
AO9 Alps Electric Co., Ltd. Target of amendment (1) The phrase “high saturation magnetic flux density” on page 2, line 13 of the specification has been changed to “Tomimata Kanka 1 Castle 1 Male □

Claims (2)

[Claims] (1) A gap plate formed to a predetermined gap length and a thin brazing material arranged on both sides of the gap plate are placed between a pair of cores made of magnetic metal, and the thin brazing material is melted to A magnetic head core characterized by a combination of cores. (2) Thin brazing material is placed on both sides of a gap plate formed to a predetermined gap length, magnetic metal blocks are further placed on both sides, and the gap plate is formed by heat-pressing at a temperature that melts the thin brazing material. , a process of forming a block in which a thin brazing material and a magnetic metal block are integrated; a process of cutting the block in a direction perpendicular to the above arrangement direction to separate it into a large number of core blocks; and forming a gap groove in the core block. A method for manufacturing a magnetic head core, comprising: a step of cutting a core block in the arrangement direction to form various front cores; and a step of joining a back core to the front core.