JPH1186208A - Manufacture of magnetic head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a magnetic head, which eliminates core breaking or the like, and prevents breaking or the like of gap parts. SOLUTION: A U-shaped core 31 and an I-shaped core 32 are butted so that the open upper parts and lower parts face each other, which forms a hole. And the U-shaped and I-shaped cores 31 and 32 are joined by providing bonding glass 33 so as to make a gap in the hole. Grooves 36 are provided across the U-shaped and I-shaped cores 31 and 32, and glass is filled in the grooves 36 for forming a core block. A pair of core blocks are prepared for joining each of the I-shaped cores 32 through non-magnetic substance therebetween. And the open lower parts of the U-shaped cores 32 are cut so that the open lower parts of the U-shaped cores 31 joined to the I-shaped cores 32 remain on the U-shaped cores 32 at least partially.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a method of manufacturing a magnetic head for writing / reading information to / from a magnetic medium.

[0002]

2. Description of the Related Art In recent years, a floppy magnetic storage device (hereinafter abbreviated as FDD) using a flexible medium has been frequently used as an external storage device of a computer.

In this FDD, a tunnel erase-type magnetic head is often used in order to maintain compatibility between mounting due to physical / mechanical deformation of a medium, FDD tracking accuracy, and the like. 3 to 5 show plan views of a magnetic head for FDD currently used. The one shown in FIG. 3 is called a laminate type and has a read / write gap 1
Read / write core 2a made of a magnetic material forming
2b is sandwiched between non-magnetic members 3a and 3b, while the core 2
Erase cores 6a and 6b forming an erase gap 5 are joined to the side surface of the non-magnetic material 4 connected to b.

The one shown in FIG. 4 is called a bulk type, in which grooves are formed on both side surfaces of read / write cores 8a and 8b forming a read / write gap 7, and the grooves are made of non-magnetic material such as glass. A groove is formed between the erase gaps of the erase cores 10a and 10b which form the erase gap 9, and a non-magnetic material such as glass is filled in the groove, and a non-magnetic material is provided between the cores 8b and 10b. They are joined together through the body.

FIG. 5 shows a so-called slide type in which an erase core 14 for forming an erase gap 13 is disposed on both sides of read / write cores 12a and 12b for forming a read / write gap 11. is there.

In recent years, as the recording density on a magnetic medium has been increased, the bulk type of the above three types of magnetic heads has come to be used particularly frequently.

The bulk type magnetic head is manufactured through the steps shown in FIG. That is, as shown in FIG. 2A, a core 21 formed of a substantially U-shaped magnetic body and a core 22 formed in an I-shape are opposed to each other, and as shown in FIG. The core block is formed by filling and fixing the bonding glass 23 into the core block, and thereafter, a groove 24 is formed on the upper surface of the core block as shown in FIG. (D), a non-magnetic body 25 is sandwiched between the core blocks, and then a grinding process is performed to obtain the shape shown in (E) of FIG. Cutting is performed at the portions A and BB to obtain the shape shown in FIG. Thereafter, although not particularly shown, a read / write coil and an erase coil are attached, and a back bar is attached to a lower end portion of a core forming a read / write gap to obtain a magnetic head.

[0008]

By the way, it is desired that the magnetic storage device has a higher density and a larger number of tracks in the future. For this purpose, not only is the track width W (see FIG. 4) reduced, but also It is necessary to reduce the gap distance L between the read / ride gap and the erase gap. To reduce the gap distance L, the thickness T of the I-shaped core (see FIG. 6F) must be reduced.

However, when the thickness T of the I-shaped core is reduced by the above-mentioned conventional manufacturing method, the following problems occur.

That is, when the thickness T is reduced, the magnetic permeability decreases, and the cross-sectional area of the magnetic path at this portion decreases, so that the magnetic resistance increases and the recording / reproducing characteristics deteriorate. There is a problem that the physical strength of the back bar mounting portion is reduced and the portion is broken when the back bar is mounted.

[0011]

SUMMARY OF THE INVENTION Accordingly, a method of manufacturing a magnetic head according to the present invention has a U-shaped first core having an open-side upper part and an open-side lower part, and an I-shaped second core. Are bonded together so that the upper and lower cores on the open side face each other and the second core faces each other, and the bonding glass is formed so that a gap is formed in a hole formed by abutting the first and second cores. And the first and second cores are joined together, a groove is provided across the first and second cores, and glass is filled in the groove to form a core block. The second cores are prepared and joined to each other via a non-magnetic material, and at least a part of the lower portion on the open side of the first core joined to the second core remains in the second core. Then, the lower portion of the open side of the first core was cut.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 is characterized in that a first core formed in a U-shape and having an upper portion on an open side and a lower portion on an open side and a second core formed in an I-shape are provided. Bonding glass is provided in the holes so that a gap is formed in a hole formed by abutting the upper and lower portions of the open side and the second core so as to face each other. A groove is provided across the groove, and the groove is filled with glass to form a core block. A pair of the core blocks is prepared, and the respective second cores are joined to each other via a non-magnetic material. The read / write gap and the erase gap are formed by cutting the open side lower part of the first core so that at least a part of the open side lower part of the first core joined to the core remains in the second core. Second to shorten the interval between Even if the core is thinned, a part of the first core is left in the second core, so that the cross-sectional area of the portion becomes large, and the magnetic resistance does not increase. Can be improved,
The risk of breakage of the second core is reduced even when the back bar is mounted. In addition, since the bonding glass is provided so that a gap is formed in a hole formed by joining the first core and the second core, the grindstone comes into contact with the bonding glass when cutting the first core, and the bonding glass is formed. Stress is accumulated, and cracks and the like can be prevented from entering the gap due to the stress relaxation of the bonding glass. In addition, by joining the pair of core blocks, the first core is cut, and a part of the first core is left on the second core. Since the cutting is performed after the second core is reinforced, the core is unlikely to be broken. Furthermore, since the groove is filled with glass after forming the groove for regulating the track width, the mechanical strength of the track portion is improved, and thereafter the core blocks are joined to each other, so that chipping of the track portion does not occur. .

According to a second aspect of the present invention, in the first aspect, the second core of the core block is ground by grinding.
By setting the thickness of the core to a predetermined thickness, the thickness of the second core can be reduced without damaging the second core.

Hereinafter, a method of manufacturing a magnetic head according to an embodiment of the present invention will be described. FIG. 1 shows a part of a manufacturing process of a magnetic head according to an embodiment.

First, a magnetic block having a rectangular parallelepiped shape is subjected to hull form processing for depth control, and a substantially U-shaped core 31 as shown in FIG. 1A and an I-shaped magnetic material are formed. An I-shaped core 32 is prepared. As shown in FIG. 2, the U-shaped core 31 is ground and lapped so that the upper portion 31b on the open side thereof is lower in height by the dimension B than the lower portion 31c on the open side. This dimension B is a dimension corresponding to a gap width described later. At this point, the upper surfaces 31a and 32a of the cores are also lapped.

The U-shaped core 31 and the I-shaped core 32 formed as described above are opposed to each other so that a gap is formed in a hole formed between the U-shaped core 31 and the I-shaped core 32. When the bonding glass 33 is provided and the gap portion is filled with the bonding glass 33 and solidified as shown in FIG.
By modulating the end portion 34 of the contact portion with the mold core 32 by the same bonding glass, the open side lower portion 31c of the U-shaped core 31 and the I-type core 32 are fixed, and the core block 35 is obtained. Thereafter, a groove 36 is formed on the upper surface 35a of the core block 35 as shown in FIG.
The groove is filled with glass and solidified.
Is ground to a predetermined size in accordance with the gap distance between the read / write gap and the erase gap. The core block 3 thus processed
5 is prepared, and as shown in FIG.
7 are sandwiched therebetween, and thereafter, a grinding process is performed so as to have a shape shown in FIG. That is, at least a part of the open-side lower part 31c of the U-shaped core 31 joined to the I-shaped core 32 is left in the I-type core 32 so that the open-side lower part 31c of the U-shaped core 31 and the I-type core 32 Is to be separated.

Then, cutting is performed at the AA portion and the BB portion to obtain the shape shown in FIG. Then, the read / write coil 38 and the erase coil 3
9 and the back bar 41 is attached to the end of the core forming the read / write gap 40 to obtain a magnetic head as shown in FIG.

The magnetic head manufactured as described above has I
Since the part which was originally a part of the U-shaped core is still joined to the lower part of the mold core 32, the magnetic path cross-sectional area of this part is the same as the conventional one (shown in FIG. 6). Since the magnetic resistance becomes larger and the magnetic resistance becomes smaller than the conventional one, the magnetic characteristics at the time of recording / reproducing become better than the conventional one. In addition, the physical strength of the portion is increased, and the risk of breakage when the back bar is attached is reduced.

[0019]

As described above, the method for manufacturing a magnetic head according to the present invention has a U-shape, a first core having an open upper portion and an open lower portion, and an I-shaped first core. No. 2 cores are joined so that the upper and lower portions on the open side and the second core face each other, and the bonding glass is formed so that a gap is formed in a hole formed by butting the first and second cores. The first and second cores are joined in the hole, a groove is provided across the first and second cores, and glass is filled in the groove to form a core block. A pair of second cores are prepared and joined to each other via a non-magnetic material, and at least a part of the open-side lower part of the first core joined to the second core remains in the second core. Cut the lower part of the open side of the first core in the same way Even if the second core is made thinner in order to shorten the gap between the gap and the erase gap, a part of the first core is left in the second core, so that the cross-sectional area of the part becomes large, and the magnetoresistance increases. And the mechanical strength of the portion can be improved, so that the risk of breakage of the second core and the like when the back bar is mounted is reduced. In addition, since the bonding glass is provided so that a gap is formed in a hole formed by joining the first core and the second core, the grindstone comes into contact with the bonding glass when cutting the first core, and the bonding glass is formed. Stress is accumulated, and cracks and the like can be prevented from entering the gap due to the stress relaxation of the bonding glass. In addition, by joining the pair of core blocks, the first core is cut, and a part of the first core is left on the second core. Since cutting after reinforcing the second core,
Core breakage is unlikely to occur. Furthermore, since the groove is filled with glass after forming the groove for regulating the track width, the mechanical strength of the track portion is improved, and thereafter the core blocks are joined to each other, so that chipping of the track portion does not occur. .

[Brief description of the drawings]

FIG. 1 is a perspective view of a core in a part of a manufacturing process of a magnetic head according to an embodiment.

FIG. 2 is a side view of a U-shaped core.

FIG. 3 is a plan view of a laminated magnetic head.

FIG. 4 is a plan view and a side view of a bulk type magnetic head.

FIG. 5 is a plan view of a straddle type magnetic head.

FIG. 6 is a perspective view of a core in a part of a conventional manufacturing process of a bulk type magnetic head.

[Explanation of symbols]

 31 U-shaped core 31b Upper open side 31c Lower open side 32 I-shaped core 33 Bonding glass 35 Core block 36 Groove 37 Non-magnetic material 38 Read / write coil 39 Erase coil 40 Read / write gap 41 Back bar

Claims (2)

[Claims] A first core formed in a U-shape and having an open-side upper part and an open-side lower part, and an I-shaped second core formed by combining the open-side upper and lower parts with the second core; Bonding glass is provided in the hole so that a gap is formed in the hole formed by abutting the cores so as to face each other, and a groove is provided between the first core and the second core. Filling glass to form a core block, preparing a pair of the core blocks, joining the respective second cores via a non-magnetic material, and joining the first core to the second core A method of cutting the lower portion of the first core so that at least a part of the lower portion of the open side remains in the second core. 2. The method according to claim 1, wherein the second core of the core block is ground to reduce the thickness of the second core to a predetermined thickness.