JPS6284409A - Manufacture of magnetic head - Google Patents

Abstract

PURPOSE:To prevent the occurrence of crack by previously inserting a nonjunction material with less capacity than that of a recessed groove into a said groove formed on one surface of two blocks becoming a core half body and filling a junction material in the recessed groove into which the nonjunction material is inserted. CONSTITUTION:A block 1 is formed with magnetic materials such as single crystal Mn-Zn ferrite or Ni-Zn ferrite, and plural recessed grooves 2 are formed in parallel at roughly the same interval (w) as track width. The bar-like or linear nonjunction material 3 formed with any materials is contained in the recessed grooves 2, and a nonmagnetic junction material 4 is melted and filled in a comparatively thick way to form an I-shaped block 5. Then a coil groove 6 extending in a direction perpendicular to the recessed grooves 2 is cut and formed. Next, a magnetic gap 8 made of nonmagnetic regulating material such as SiO2 is formed by any thin film forming means on the surface at the magnetic gap forming side of one core block. Finally a core block 9 jointed in one body is sliced. Thus such a trouble that junction strength deteriorates to develop a crack can be eliminated.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention is applicable to a video tape recorder (hereinafter referred to as VTR) or a floppy disk drive (hereinafter referred to as FDD).
The present invention relates to a method of manufacturing a magnetic head suitable for magnetic recording/reproducing devices that require high-density recording, such as those described above.

[Conventional technology]

In recent years, increasing recording density has become one of the most important technical issues in magnetic recording and reproducing devices such as VTRs and FDDs. One possible means for solving this technical problem is to narrow the recording tracks and increase the number of recording tracks per unit area, thereby improving the recording density accordingly. In order to narrow the recording track, it is necessary to narrow the track width of the magnetic head for writing information on the magnetic recording medium and reading information recorded on the magnetic recording medium, and from this point of view,
2. Description of the Related Art Magnetic heads in which the track width is narrower than the core width are conventionally known.

FIG. 1O shows an example of a conventionally known magnetic head of this type. As shown in this figure, this type of magnetic head has M
The gap forming side of the I-shaped core half 1 (1) made of a material with high magnetic permeability and saturation magnetic flux density such as n-Zn ferrite, and the C-shaped core half 11 made of a similar material. S i is formed on the gap forming side surface of the ■-shaped core half body 10 and the C-shaped core half body 11.
A magnetic gap 12 made of a non-magnetic material such as 02 is formed, and a bonding material 14 is filled in a recess 13 formed on the side surface of the gap forming side of the I-shaped core half 10 and the C-shaped core half 11. As a result, the I-shaped core half 10 and the C-shaped core half 11 are joined. In this figure, reference numeral 15 indicates a winding window, and illustration of the excitation coil is omitted.

An example of a method for manufacturing such a magnetic head will be outlined below with reference to FIGS. 11 to 17.

First, as shown in FIG. 11, a predetermined track width (
A plurality of grooves 21 are formed in parallel at intervals W equal to the width d) in FIG. 10.

Next, as illustrated in FIG.
A non-magnetic bonding material 22 such as bO2 is melted and filled to a relatively thick thickness, and then polished to the position shown by the dashed line in the same figure to form the ■-shaped core half 10 as shown in FIG. A shaped core block 24 is formed.

Further, a coil groove extending in a direction perpendicular to the groove 21 is cut into a part of the block 20 shown in FIG. By melting and filling a relatively thick bonding material 22 similar to the above, and then removing unnecessary bonding material 22, a C-shaped core block 26 in which a coil 1lt25 is formed is formed, as shown in No. 14.

Next, as shown in FIG. 15, the surface of at least one of the I-shaped core block 24 and C-shaped core block 24, 26 on the gap forming side is subjected to a process such as sputtering or vacuum evaporation. using thin film forming means.

A magnetic gap 27 made of a non-magnetic gap regulating material such as 5 iOz is deposited.

Next, as shown in FIG. 16, the magnetic gap forming side surfaces of the I-shaped core block 24 and the C-shaped core block 26 to which the magnetic gap 27 is attached are butted together, and preset pressurization and heating conditions are applied. Both core blocks 24 under
．． 26 is joined.

Finally, as shown in FIG. 17, the core block 28 that has been joined together as described above is sliced along the dashed line shown in the same figure to obtain a predetermined shape as shown in FIG. obtain a magnetic head.

By the way, when manufacturing a magnetic head by the method described above, there is a machining margin of about 0.5 m to 1 cm between the parts of the core block 28 that will become the magnetic head after slicing. A gap must be set. Various methods can be considered to increase the machining allowance = 4-, but usually, in order to facilitate machining, the core width T is increased as shown in Fig. 11.
The groove 21 is formed with a width wider than that of the groove 21.

[Problems with the prior art] However, if the width of the groove 21 is made wide as in the conventional technique, the total amount of the bonding material 22 filled in the groove 21 increases, and the bonding process, especially heating, increases accordingly. During the cooling process, air bubbles are likely to be generated in the bonding material 42, or the difference in volume shrinkage l between the core block 28 and the bonding material 22 becomes large during the cooling process, causing problems such as cracks in the bonding material 22. .

For this reason, in conventional magnetic heads, air bubbles generated in the bonding material 22 may be exposed to the medium sliding surface side, impairing the smoothness of the medium sliding surface, or reducing the bonding strength of the core block. This often results in problems such as wide variations in gap length or separation of the ■-shaped core half 10 and the C-shaped core half 11 from the joint surface during handling, resulting in a poor yield. There was a problem.

[Means for solving problems]

The present invention reduces the amount of bonding material filled between two core blocks to be bonded.
In order to reduce air bubbles generated in the bonding material during cooling and cracks caused by these, and thereby provide a magnetic head with high yield and stable magnetic properties, we developed two blocks that form the basis of the core halves. A non-bonding material with a volume smaller than the volume of the groove is inserted in advance into a groove formed on one side of the block, and the bonding material is filled into the groove of the block into which the non-bonding material is inserted. It is characterized by the fact that it is made to do so.

〔Example〕

An example of a method for manufacturing a magnetic head according to the present invention will be described below with reference to FIGS. 1 to 9.

First, as shown in FIG. 1, for example, single crystal Mn-Zn
Using a magnetic material such as ferrite or Ni-Zn ferrite, a block 1 that will become the basis of the I-shaped core half and the C-shaped core half is formed.

Next, as shown in FIG. 2, a plurality of grooves 2 are formed in parallel on one side of the block 1 at intervals W that are approximately equal to the required track width.

Next, as shown in FIG. 3, for example, graphite, MoSi2. A rod-shaped or linear non-bonding material 3 made of any material such as ceramics such as h-BN, heat-resistant polymer materials such as polyimide, or metal materials such as copper is housed.

Next, as shown in FIG. 4, a non-bonding material such as a low melting point glass containing Pb0z as a main component is placed inside the groove 2 in which the non-bonding material 3 is housed as described above and on the gap forming side surface of the block 1. A relatively thick magnetic bonding material 4 is melted and filled, and then polished to the position shown by the dashed line in the figure to form a square-shaped core block 5 as shown in FIG.

Next, as shown in FIG. 6, a coni-tool [6] extending in a direction perpendicular to the groove 2 is cut into a part of the plurality of I-shaped core blocks 5 formed as described above. , forming a C-shaped core block 7.

Next, as shown in FIG. 7, the magnetic gap forming side surface of either the ■-shaped core block 5 or the C-shaped core block 7 is subjected to a process such as sputtering, vacuum deposition, chemical vapor deposition, or plating. For example, 5iOz, 1"i, C
A magnetic gap 8 made of a non-magnetic gap regulating material such as U or Be is formed.

Next, as shown in FIG. 8, the magnetic gap forming side surfaces of the I-shaped core block 5 and the C-shaped core block 7 to which the magnetic gap 8 has been adhered are butted together, and preset pressurization and heating conditions are applied. Join below.

Finally, as shown in FIG. 9, the core block 9 that has been joined together as described above is sliced along the dashed-dotted line in the same figure to obtain a predetermined shape that does not include the non-joint material. obtain a magnetic head.

In the manufacturing method of the magnetic head of the above embodiment, the non-bonding material 3 is inserted into the recess WIt2 and then the bonding material 4 is filled, so that the total amount of the bonding material 4 filled in the recess [92] It is reduced by about 32%, and the air bubbles generated inside the intervening bonding material 4 are reduced. Therefore, it is possible to eliminate problems such as air bubbles coming out on the medium sliding surface side of the magnetic head, impairing smoothness, or lowering the bonding strength and causing cracks.

The gist of the present invention resides in a method of filling a bonding material to join two core halves, and the structure of the core halves constituting the magnetic head is limited to that of the above embodiment. isn't it. For example, Fe-8i alloy,
Composite magnetic heads with metal magnetic layers made of crystalline magnetic alloys with high magnetic permeability and high saturation magnetic density, such as Fe-Al-8i alloy and Ni-Fe alloy, or amorphous magnetic alloys, are also covered. It can be implemented in exactly the same way.

Furthermore, in the above embodiments, a case was explained in which a non-bonded material formed in a rod shape or a linear shape was used, but the gist of the present invention is not limited to this, and any other shape of non-bonded material may be used. Can be used.

Furthermore, in the above embodiment, PbO2 is used as the bonding material.
However, the gist of the present invention is not limited to this, and it goes without saying that any other bonding material may be used.

〔Effect of the invention〕

As explained above, in the method for manufacturing a magnetic head of the present invention, the non-bonding material is inserted into the groove and then the bonding material is filled, so the total amount of bonding material filled in the groove is The amount of air bubbles generated inside the intervening material is reduced. Therefore, it is possible to eliminate problems such as air bubbles forming on the medium sliding surface side of the magnetic head, impairing smoothness, or reducing bonding strength and causing cracks.

[Brief explanation of drawings]

1 to 9 are process diagrams showing an example of a method for manufacturing a magnetic head according to the present invention, in which FIG. 1 is a perspective view of a block that is the basis of a core half, and FIG. 2 is a concave groove. Fig. 3 is a front view of the block with non-bonding material inserted, Fig. 4 is a front view of the block filled with bonding material, and Fig. 5 is a perspective view of the I-shaped core block. Figure 6 is a perspective view of a C-shaped core block, Figure 7 is a perspective view of a core block with a magnetic gap formed, Figure 8 is a front view showing a method of joining the core blocks, and Figure 9 is a core block. 10 is a perspective view showing an example of a conventionally known magnetic head, and FIGS. 11 to 17 are process diagrams showing an example of a conventionally known magnetic head manufacturing method. Fig. 11 is a perspective view of a block with grooves formed therein, Fig. 12 is a front view of a block filled with bonding material, Fig. 13 is a perspective view of a ■-shaped core block, and Fig. 14 is a C-shaped core block.
FIG. 15 is a perspective view of a core block in which a magnetic gap is formed, and FIG. 16 is a front view showing a method of joining the core blocks. FIG. 17 is a front view showing the slice position of the core block. 1 Ni block, 2: Concave groove, 3: Non-bonded material, 4: Bonded material,
5: Type 1 core block, 6: Coil groove. 7: C-shaped core block, 8: Magnetic gap, 9 integrated core block Figure 9 Figure 10 Figure 11 Figure 12 Figure 13

Claims (1)

[Claims] A step of forming a plurality of grooves in parallel at intervals approximately equal to the track width on one side of two blocks that will become the base of the core halves, and forming a non-concave groove in the grooves with a volume smaller than the volume of the grooves. A process of inserting a bonding material, a process of filling the bonding material into the groove of the block into which the non-bonding material has been inserted, a process of polishing the gap forming side surface of the block to expose the gap abutment part, and a gap. A step of forming a non-magnetic magnetic gap on the gap forming side surface of at least one of the two blocks with exposed abutting portions; A method for manufacturing a magnetic head, comprising the steps of butting the surfaces and joining both blocks together, and slicing the joined blocks to take out a magnetic head of a predetermined shape that does not contain the above-mentioned non-bonding material. .