JPH0250307A - Manufacture of magnetic head - Google Patents

Abstract

PURPOSE:To surely fill a bonding agent in the gap of a block of magnetic material by filling the bonding agent having a main component of water glass in the gap between blocks of magnetic material, and heating and hardening the bonding agent. CONSTITUTION:In a state where gap forming planes 6, 6 at the blocks 11 and 12 of magnetic material are stuck oppositely with each other and a bar 16 is inserted to an internal winding groove 4, the bonding agent 17 having the main component of water glass is filled in track grooves 8... and filling grooves 3, 3, and after that, the bar 16 is removed. The bonding agent 17 in the track grooves 8... and the filling grooves 3, 3 is heated and hardened by heating the blocks 11 and 12 of magnetic material, and a pair of blocks 11 and 12 of magnetic material can be fixed with each other. In such a way, it is possible to fill the bonding agent 17 and to harden it surely even in the track grooves 8... having complicated shape.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention is applicable to VTR [video tape're
The present invention relates to a method of manufacturing a magnetic head that requires high-density recording, such as a magnetic head that requires high-density recording.

[Conventional technology]

Magnetic heads such as VTRs need to perform high-density recording and reproduction. Therefore, this magnetic head uses a core in which a thin film made of an alloy magnetic material having high magnetic permeability and high saturation magnetic flux density is formed on the gap-opposing surface of a block made of an oxide magnetic material having high magnetic permeability.

A method of manufacturing such a conventional magnetic head will be explained based on FIGS. 11 to 19.

First, as shown in FIG. 11, an outer winding groove 2 and a filling groove 3 are formed in one oxide magnetic material block 1 made of an oxide magnetic material, and an inner winding groove 4 is further formed. Further, as shown in FIG. 12, the other oxide magnetic material block 5 also made of oxide magnetic material has an external winding groove 2.
and a filling groove 3 are formed.

Next, as shown in FIGS. 13 and 14, a plurality of track grooves 8 are formed on one end side of the gap forming surface 6 of the oxide magnetic material block 5, respectively.

When the track grooves 8... are formed, FIGS.
As shown in FIG.
Then, alloy magnetic thin films 10 made of an alloy magnetic material are formed on the inner surface of the track groove 8. As a result, a pair of magnetic material blocks 11 and 12 are formed in which the oxide magnetic material block 5 and the alloy magnetic thin films 10 and 10 are combined. Further, a non-magnetic thin film (not shown) is formed on the alloy magnetic thin film 10 of one of the magnetic material blocks 11 or 12 formed in this manner.

Once the non-magnetic thin film is formed, as shown in FIG.
In the gaps formed by the internal winding grooves 4, rod-shaped materials of the glass fillers 13 are placed, respectively.

Then, heating is performed in this state and the glass filler material 13.
When it is melted, as shown in FIG. 18, the glass fillers 13 are filled in the upper part of the internal winding groove 4, in each track groove 8..., and in the filling grooves 3 and 3, making it magnetic. The material blocks 11 and 12 are welded together. Note that FIG. 17 is shown upside down from FIG. 18.

Thereafter, the tape sliding surfaces 7 are polished to give a curvature, and then cut along the two-dot chain line shown in the figure to complete the core 14 of the magnetic head shown in FIG. 19.

Therefore, the core 14 of this magnetic head is made up of a pair of cut magnetic material blocks 11 and 12 that are closely attached at the top and bottom with a non-magnetic thin film interposed therebetween. The width of the opposing portion of this upper contact portion is regulated by the track grooves 8 on both sides, and a magnetic gap 15 having a predetermined gap width is formed.
becomes. Note that the lower contact portion has a sufficiently large area that the influence of the nonmagnetic film can be ignored.

In addition, a glass filler 13 is filled in the gap between the magnetic material blocks 11 and 12 other than the close contact part, except for most of the lower part of the internal winding groove 4, so that the magnetic material blocks 11 and 12 are mutually connected to each other. It will be welded.

The core 14 is constructed by winding a coil between the gap of the internal winding groove 4 and the external winding groove 2 formed on the outer surface of each magnetic material block 11 and 12. Becomes the head.

[Problem to be solved by the invention]

However, in the manufacturing process of such a core 14, the magnetic material blocks 11 and 12 may be contaminated, the non-magnetic thin film constituting the magnetic gap 15 may be non-uniform, or the glass itself as a filler may be non-uniform. If they are homogeneous, the wettability of the glass fillers 13 will be poor and the corners of gaps such as the track grooves 8 will not be filled sufficiently.

Therefore, in the conventional magnetic head manufacturing method, the glass fillers 13 are not filled sufficiently, resulting in a problem that the yield during manufacturing the magnetic head deteriorates.

[Means to solve the problem]

In order to solve the above problems, a method for manufacturing a magnetic head according to the present invention includes a method for manufacturing a magnetic head in which a core is formed by fixing a pair of bonded magnetic material blocks to each other with an adhesive. By fixing and holding the blocks together, filling the predetermined gaps between the magnetic material blocks with an adhesive mainly composed of water glass, and heating and curing the filled adhesive, the magnetic material blocks It is characterized by being fixed to each other.

[Function] First, a pair of magnetic material blocks are bonded together and fixed and held using a jig or the like.

Conventionally, glass rods placed in the gaps between magnetic material blocks are heated and melted to fill the gaps with glass as an adhesive. Therefore, if the wettability of the glass deteriorates due to dirt or the like on the magnetic material block, the molten glass will not penetrate to the corners of the gap, resulting in insufficient filling.

However, in the present invention, a predetermined gap is filled in advance with an adhesive mainly composed of water glass having appropriate fluidity, and then this adhesive is heated and hardened to fix the magnetic material blocks. .

Therefore, the adhesive will always fully fill the predetermined gaps between the blocks of magnetic material. Furthermore, since water glass is used as the adhesive, performance similar to that obtained when conventional glass fillers are used can be obtained.

Note that this water glass-based adhesive does not need to be used in all gaps that should be filled with adhesive; it has traditionally been used in areas where it is easy to fill, such as filling grooves. Alternatively, low melting point glass may be melted during heating and filled.

(Embodiment) An embodiment of the present invention will be described below based on FIGS. 1 to 10. For convenience of explanation, the conventional example shown in FIGS. The same reference numerals are given to the same components.

The magnetic head manufactured in this example uses an oxide magnetic material with high magnetic permeability and an alloy magnetic material with high magnetic permeability and high saturation magnetic flux density in order to perform high-density recording on a magnetic recording medium with high coercive force. Composite materials with other materials are used as magnetic materials. Therefore, first, a pair of oxide magnetic material blocks 5 made of oxide magnetic material are prepared. The blocked oxide magnetic material 5 has a size that allows a plurality of magnetic head cores to be manufactured at once.

Then, as shown in FIG. 1, an external winding groove 2 and a filling groove 3 are formed in one of the oxide magnetic material blocks 1, and an internal winding groove 4 is further formed. Further, in the other oxide magnetic material block 5, as shown in FIG. 2, an external winding groove 2 and a filling groove 3 are formed. The filling grooves 3 are each provided on the gap forming surface 6 of the blocked oxide magnetic material 5,
One side is open reaching the end face of the blocked oxide magnetic material 5. The gap forming surface 6 is a surface on which a magnetic gap 15 will later be formed at the end opposite to the filling groove 3. Further, the end surface of the gap forming surface 6 that is perpendicularly in contact with the end portion where the magnetic gap 15 will be formed later becomes the tape sliding surface 7. The internal winding groove 4 is formed parallel to the filling groove 3 in a portion of the gap forming surface 6 of the oxide magnetic material block 1 closer to the tape sliding surface 7 . The external winding groove 2 is formed on the surface of each oxide magnetic material block 5 opposite to the gap forming surface 6.

Next, as shown in FIGS. 3 and 4, the gap forming surface 6 and the tape sliding surface 7 of the blocked oxide magnetic material 5 are
is polished to a mirror surface, and a plurality of track grooves 8 are formed on each gap forming surface 6. Trunk groove 8...
is formed perpendicularly to the longitudinal direction of the gap forming surface 6 on the tape sliding surface 7 side of the gap forming surfaces 6 divided into both sides by the internal winding groove 4 for the oxide magnetic material block 1. be done. Further, the oxide magnetic material blocks 5 are each formed from near the center of the gap forming surface 6 to the tape sliding surface 7.

Note that the space between each of the track grooves 8 becomes the gap width of a magnetic gap 15 that will be formed later.

When the track grooves 8... are formed, as shown in FIGS. 5 and 6, after etching away the process-affected layer formed on the gap forming surface 6 for each oxide magnetic material block 5, , an alloy magnetic thin film 10 made of an alloy magnetic material is formed on the gap forming surface 6 and on the inner surfaces of the filling groove 3, the internal winding groove 4, and the track groove 8 by sputtering.
form. As a result, a pair of magnetic material blocks 11 and 12 are formed in which the oxide magnetic material block 5 and the alloy magnetic thin films 10 and 10 are combined. Further, on the alloy magnetic thin film lO of one of the magnetic material blocks 11 or 12 thus formed, a non-magnetic thin film (not shown) made of Sin or the like is formed to a thickness of about 0.3-. Note that the thickness of this nonmagnetic thin film becomes the gap length of the magnetic gap 15 that will be formed later.

When the non-magnetic thin film is formed, as shown in FIG.
・With the six mats facing each other and the rod 16 inserted into the internal winding groove 4, an adhesive 17 mainly composed of water glass is applied inside the track groove 8 and filling groove 3. Fill it within 3. Since the adhesive 17 is mainly composed of water glass and has appropriate fluidity, it can be reliably filled into the track grooves 8 and the like. Note that the bar 16 is provided to prevent the internal winding groove 4 from being completely filled with the adhesive 17.

However, since the filling grooves 3 have a simple home base shape with a pentagonal cross section, it was possible to easily and reliably fill them with the conventional glass filler 13.

Therefore, in this embodiment as well, as shown in FIG. 8, the adhesive 17 mainly composed of water glass is filled only in the track grooves 8, and the filling grooves 3 are filled with the adhesive 17 as in the conventional case. A rod-shaped material of the glass filler 13 having a low melting point may be placed thereon.

When the filling of the adhesive 17 and, if necessary, the placement of the glass filler 13 are completed, the bar 16 is pulled out, and with the magnetic material blocks 11 and 12 stuck together, it is turned upside down and fixed with a jig. When the magnetic material blocks 11 and 12 are heated, the adhesive 17 in the track grooves 8 and the filling grooves 3 is heated and hardened. In addition, glass filler 13
When this is used, it is heated and melted and filled into the filling grooves 3.

As a result, as shown in FIG. 9, the adhesive 17 is cured with being filled in the track grooves 8 and the filling grooves 3, and in some cases, the adhesive 17 is cured in the filling grooves 3 and 3. Glass filler 13 is melt-filled to form a pair of magnetic material blocks 11.
- 12 are fixed to each other. Therefore, the adhesive 17 can be reliably filled and cured even in the track grooves 8 having a complicated shape. Note that the adhesive 17 is filled and hardened not only in the track groove 8 .

Once the magnetic material blocks 11 and 12 are fixed in this way, the tape sliding surfaces 7 and 7 are polished to give them a curvature, and then cut along the two-dot chain line in the figure to create a magnetic head as shown in FIG. 1O. Complete the core 14 of.

Therefore, the core 14 of this magnetic head is made up of cut magnetic material blocks 11 and 12 that are closely attached at the top and bottom with a non-magnetic thin film interposed therebetween. The width of the opposing portion of this upper contact portion is regulated by the track grooves 8 on both sides, forming a magnetic gap 15 having a predetermined gap width. Note that the lower contact portion has a sufficiently large area that the influence of the nonmagnetic film can be ignored.

In addition, an adhesive 17 is filled and hardened in the gap between the magnetic material blocks 11 and 12, except for the part closed by the bar 16 of the internal winding groove 4. The glass filler 13 is filled only in the filling grooves 3 and 3,
This means that the magnetic material blocks 11 and 12 are fixed to each other. For this reason, conventional glass filler 1
The decrease in yield caused by defective filling in No. 3 can be almost completely eliminated.

The core 14 becomes a magnetic head by winding coils between the gap of the internal winding groove 4 and the external winding grooves 2 formed on the outer surface.

〔Effect of the invention〕

As described above, the method for manufacturing a magnetic head according to the present invention includes:
In a method of manufacturing a magnetic head in which a core is formed by fixing a pair of magnetic material blocks bonded together with an adhesive, a pair of magnetic material blocks are fixed and held in a bonded state, and a predetermined distance between the magnetic material blocks is The magnetic material blocks are fixed to each other by filling the gap between the gaps with an adhesive whose main component is water glass and heating and curing the filled adhesive.

This reliably fills the gap between the pair of magnetic material blocks constituting the core with the adhesive.

Therefore, the present invention has the effect of improving the yield when manufacturing magnetic heads.

[Brief explanation of the drawing]

1 to 10 show one embodiment of the present invention, FIGS. 1 to 9 are perspective views showing each manufacturing process of a magnetic head, and FIG. 10 is a diagram of a completed magnetic head. FIG. 3 is a perspective view of the core. 11 to 19 show a conventional example, and FIGS. 11 to 18 are perspective views showing each manufacturing process of the magnetic head, and FIG. 19 is a perspective view of the core of the completed magnetic head. It is. 11 and 12 are magnetic material blocks, 14 is a core, and 17 is an adhesive. Figure 11 Figure 12 Figure 9 Figure 10tl Figure 13 Figure 14 Figure 15 Figure 17

Claims (1)

[Claims] 1. In a method for manufacturing a magnetic head in which a core is formed by fixing a pair of magnetic material blocks bonded together with an adhesive, the pair of magnetic material blocks are fixedly held in a bonded state. , the magnetic material blocks are fixed to each other by filling a predetermined gap between the magnetic material blocks with an adhesive mainly composed of water glass and heating and hardening the filled adhesive. Head manufacturing method.