JPH01267808A - Manufacture of floating type composite magnetic head - Google Patents

Abstract

PURPOSE:To improve reliability without generating butting by processing specularly a slider face, after that, forming two parallel grooves almost perpendicular to a magnetic gap forming face and regulating a track width. CONSTITUTION:A V-shaped groove 36 is formed on a butting face 32a of a first ferrite block, metal magnetic material is bonded and filled in this groove 36 and after that, a coil grove 33 is formed on the butting face 32a. This face 32a is specularly processed, a second ferrite block to form a core slider part and a first block are butted through a magnetic gap material 34 and they are bonded together by glass welding. Next, a slider face 31 is specularly processed, after that, the two parallel grooves almost perpendicular to the magnetic gap 34 forming face and thus, the track width is regulated. Thus, molding glass may be only one type of bonding glass to bond the slider part and a core half body 32, therefore, the two can be firmly bonded, the dislocation of the track width does not occur at the time of the butting and a highly reliable floating- type magnetic head can be manufactured.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a floating magnetic head that performs magnetic recording and reproduction in a minute floating state relative to the surface of a magnetic recording medium, and particularly relates to a floating magnetic head having a monolithic type composite core. This invention relates to a floating magnetic head.

(Prior art and problems to be solved) Conventionally, magnetic heads for hard disk drives that perform magnetic recording and playback on so-called hard disks with hard recording media surfaces have a magnetic head that levitates at a small distance from the hard disk. A slider section with an air bearing surface (hereinafter referred to as ABS surface) for magnetic recording,
A floating magnetic head is used, which includes a magnetic head section that performs reproduction.

Recently, in magnetic recording and reproducing devices using hard disks, magnetic metals with high coercive force are used as recording bodies to increase recording density. A ferrite magnetic material with excellent frequency characteristics is used in the magnetic circuit, and the saturation magnetic flux density is high near the magnetic gap where the magnetic flux is most concentrated, e.g.
Various floating magnetic heads having so-called composite cores formed with ferromagnetic metal films such as Sendust (registered trademark) have been devised and put into practical use.

FIG. 13(a) is a perspective view of a conventional pitch-type magnetic head 10, and FIG. 13(b) is a plan view showing the recording medium sliding surface in FIG. 13(a).

Generally, it is well known that the bonding surface 13 between the ferrite magnetic material 11 and the ferromagnetic metal film 12 acts as a pseudo gap on the tape sliding surface 14, and generates noise due to interference in the reproduced waveform. In this case, it is well known that when the bonding surface 13 is parallel to the magnetic gap 15, the effect is strong. FIG. 14 is an explanatory diagram for explaining a state in which an abnormal peak occurs in an isolated reproduced waveform, for example, in digital recording that handles pulses.

During playback, as shown in the figure, this effect is as follows:
There is a problem in that an abnormal peak portion 17 occurs in the isolated reproduced waveform 16 due to the pulse, which may cause malfunction of the device. FIG. 15(a) is a perspective view of another conventional composite magnetic head 20, and FIG. 15(b) is a plan view showing the recording medium sliding surface of FIG. 15(a).

As shown in the figure, bonding surfaces 21a and 22a are used to bond ferromagnetic metal films 23 and 24 to magnetic core halves 21 and 22 made of ferrite magnetic material constituting the magnetic head section 20.
There is a structure in which the magnetic field is inclined with respect to the magnetic gap 25. However, in this magnetic head 20,
A eraser 26 for regulating the width of the magnetic gap 25 is formed so as to face the ferromagnetic metal films 23 and 24, and is wound in the figure-7 groove formed by these grooves 26 and the ferromagnetic metal films 23 and 24. Although a part of the line groove 27 is filled with molded glass 28, this figure-7 groove picks up signals from adjacent tracks (not shown), which tends to deteriorate crosstalk characteristics. Since the molded glass 28 was exposed to the sliding surface of the recording medium, there was a problem in terms of reliability.

16 rlJ (a) to (h) are shown in Fig. 15 (a)
).

FIG. 3 is an explanatory diagram for explaining the main manufacturing process of another conventional composite magnetic head 20 shown in FIG.

First, as shown in Figure (a), a plurality of 7-shaped grooves 26 are spaced apart from each other by a certain distance and parallel to each other in a block-shaped core half 21 (22) made of ferrite magnetic material. Form individuals.

Next, as shown in FIG. 4B, the first molded glass 28-1 is melted and filled into the groove 26.

Next, as shown in FIG. 3(c), a 7-shaped groove is formed between the plurality of grooves 26 so as to be in contact with the grooves 26 on both sides, thereby forming a bonding surface 21a (22a). The same figure (d
), a metal magnetic film 23 (24) is placed so as to cover the bonding surface 21a (22a) and the molded glass 28.
After forming by sputtering, a protective film 29 is formed by sputtering as shown in FIG. 2(e), and a second mold glass 28-
After filling the groove by melting and filling 2, the same figure (f
), one of the block-shaped magnetic core halves 21 is polished to a flat surface.
), one magnetic core half 21 provided with a winding groove 27 is used as the other block-shaped magnetic core half 22.Next, as shown in FIG. The one and the other magnetic core halves 21 and 22 are butted together via a magnetic gap material, and a third molded glass 2 is inserted into the winding groove 27.
Re-magnetic core halves 21.22 by melt-filling 9.
The conventional composite magnetic head 20 shown in FIG. 15 is obtained by joining the two parts together and then cutting along the cutting lines E and A'-'.

As is clear from the above steps, the first molded glass 2
8-1, since it is necessary to use three types of molded glass: the second molded glass 28-2 and the third molded glass 299, the temperature of the glass must be lowered sequentially from the previous process, and the glass temperature in the subsequent process Because it is necessary to use low melting point glass, the adhesive strength of the glass decreases as it progresses to later stages.
Moreover, since the glass is exposed on the sliding surface of the medium, there is a problem in that reliability is lacking during use.

Furthermore, since the track width is determined by the thickness of the metal magnetic films 23 and 24, it is necessary to strictly control the film thickness during the manufacturing process.

Also, as the track width becomes narrower, naturally the metal magnetic film 23.2
Since the thickness of No. 4 is also thinner, there is a problem that butts are likely to occur in the butt step.

(Means for Solving the Problems) The present invention has been made to solve the above problems, and includes a core slider portion having a slider surface and forming one magnetic core half, and a winding groove. The other magnetic core half is made of a ferrite magnetic material, and a metal magnetic material is formed near the magnetic gap forming part of the other magnetic core half on a bonding surface that is non-parallel to the forming surface of the magnetic gap. In the method of manufacturing a floating magnetic head constructed by bonding, a step of forming a groove in the shape of a 7 on the abutting surface of the first ferrite block, after adhering and filling the groove with gold R magnetic material, forming the winding groove on the abutting surface and mirror-finishing the abutting surface; butting the second ferrite block for forming the core slider portion and the first block via a magnetic gap material; , a step of joining them together by glass welding, and after mirror-finishing the slider surface, two parts substantially perpendicular to the magnetic gap forming surface.
It is an object of the present invention to provide a method for manufacturing a floating type composite magnetic head characterized in that the track width is defined by forming parallel grooves.

(Example) FIG. 1 shows a floating magnetic head 30 according to the manufacturing method of the present invention.
FIG. 2 is a partially enlarged view showing the vicinity of the magnetic gap, which is the essential part of the invention of the floating magnetic head 30 shown in FIG. 1. In FIGS. 1 and 2, 31 is a slider portion that also serves as one half of the magnetic core made of ferrite magnetic material, and 32 is the other half of the magnetic core made of ferrite magnetic material. Abutment surface 32 of magnetic core half body 32
A winding groove 33 is formed in a, and a part of the abutting surface 32a in front of the winding groove 33 has a joining surface 3 for joining the ferromagnetic metal M35, which is inclined with respect to the magnetic gap 34.
6a is formed, and a first
The ferromagnetic metal l1i35 surface forms one magnetic gap 34 forming surface.

37 is a coil wound using the winding groove 33.

The slider portion 31 has an ABS surface 38, and the other magnetic core half 32 is integrally joined to the end of the ABS surface 38 at the center of the end surface 39 via a gap material made of a non-magnetic material. , the magnetic gap 3 is flush with the ABS surface 38.
4 and the width of this magnetic gap 34 is AB
It is regulated by the width t of the center rail 38a formed by two substantially parallel tapered grooves 40 formed in the S surface 38, and forms a substantial track width.

More specifically, the tapered groove 40 consists of a vertical portion 40a and an inclined portion 40b, and the track width is regulated by the inclined portion 40b. Reference numerals 41 and 42 are adhesive glasses, and the abutment surface 32 between a part of the winding groove 33 and the magnetic core half body 32
It is melted and filled into the bonding groove 43 formed in a to bond the magnetic core half 32 and the slider 31 together. 44 and 45 are tapered portions for air inflow and outflow, which are formed at the ends of the slider portion 31 and the magnetic core half body 32, respectively. Reference numeral 46 denotes a mounting groove, which is used to attach to a mounting tool (not shown).

As mentioned above, the bonding surface 3 of the floating magnetic head 30 of the present invention
6a is configured to be inclined with respect to the magnetic gap 34 on the ABS surface 38, so that it does not become a pseudo gap, and when used, an abnormal peak 18 occurs in a part of the isolated reproduction waveform 17 as shown in FIG. In addition, since the ends of the magnetic gap 34 are regulated by two substantially parallel tapered grooves 40, the ends of the magnetic gap 34 have a figure 7 groove or are free from core misalignment. There is no right-angle wiping and therefore no crosstalk due to adjacent track signals.

Next, a method of manufacturing the magnetic head 30 according to the present invention will be explained.

3 to 11 are schematic explanatory diagrams showing the manufacturing process of the floating magnetic head according to the present invention shown in FIGS. 1 and 2, and will be explained below with reference to each figure.

As shown in FIG. 3, a block-shaped magnetic core half 32 made of a ferrite magnetic material is prepared, and a plurality of V-shaped grooves 36 having an inclined joining surface 36a are placed at a predetermined interval on the abutting surface 32a. Form.

Next, as shown in FIG. 4, ferromagnetic metal WA35 was provided on the bonding surface 36a consisting of the figure-7 grooves 36 by thin film forming means such as sputtering, and these figure-7 grooves 36 were filled with the ferromagnetic metal WA35. Afterwards, the abutting surface 32a is finished into a mirror finish.

Next, as shown in FIG. 5, the winding grooves 33 are formed on the abutting surfaces 32a of the magnetic core halves 32 so as to communicate with the bonding surfaces 36a, and the corners for the bonding grooves 43 are cut. The surface 32a is polished to a mirror surface, and a nonmagnetic film (not shown) made of 8102 or the like is formed.

Next, as shown in FIG. 6, a block-shaped slider 31 made of ferrite magnetic material is prepared, and the end surface 39 of the ABS surface 38 is polished to a mirror finish to form a butt surface, and as described above, an 810° angle A nonmagnetic film is formed.

Next, as shown in FIG. 7, this abutting surface 32a and the slider 3
1 and then the winding groove 33 and the joining groove 4.
The slider 31 and the magnetic core half 32 are integrally joined by melting and filling adhesive glasses 41 and 42 into the slider 31 and the magnetic core half 32.

Next, as shown in FIG. 8, the ABS surface 38 of the slider 31
After forming the mounting 7I446 on the back side of the slider 31, a pair of parallel grooves 40 are formed on the ABS surface 38 so as to be substantially perpendicular to the magnetic gap 34 formed between the ferromagnetic metal film 35 and the end surface 39 of the slider 31. By forming the center rail 38a, the magnetic heads are separated into individual magnetic heads 48 along the cutting grooves 47. Next, as shown in FIG.
Tapered portions 44° and 45 for air inflow and outflow are formed on the surface 38.

Next, as shown in FIG. 11, an inclined portion 40b is formed on the center rail 38a, and a part of the magnetic core half 32 except for the center rail 38a is removed by cutting, and the winding groove 40b is removed.
By winding the winding 37 around the magnetic head 3, the floating magnetic head 30 shown in FIGS. 1 and 2 can be obtained. 1st
FIG. 2 is a plan view showing the vicinity of the magnetic gap, and in this figure, the shaded area shows the removed portion of the magnetic core half 32.

In the above example, as shown in FIG. 3, an example was explained in which the figure-7 groove 36 has a groove width parallel to the abutment surface 32a of the block-shaped magnetic core halves and has an inclined joint surface 36a. As another embodiment, a short 7-shaped groove 36 is formed only at one end of the abutting surface 32a so as to communicate with the winding groove 33, and a metal magnetic material 35 is attached and filled in this short 7-shaped groove 36. It can be easily understood by referring to FIG.

As described above, according to the manufacturing method of the present application, it is only necessary to use one type of adhesive glass 41 and 42 for bonding the slider 31 and the magnetic core half 32.
It is easy to select the glass, and the temperature can be selected high, making it possible to form a strong bond. Further, since no glass portion is present on the abutting surface 32a of the other magnetic core half 32, polishing conditions are advantageous, and a flat abutting surface 32a is easily obtained, which is advantageous when forming a narrow magnetic gap.

Further, the metal magnetic material 35 is formed only on the other magnetic core half 32, and no metal magnetic material is provided on the slider 31 side, and the track width t is defined by the interval between the two parallel erasers 40b. Therefore, there is no risk of track width deviation occurring during abutting, and since there is no glass portion on the recording medium sliding surface, it is possible to manufacture a floating type composite magnetic head with less wear and tear.

(Effects of the Invention) As described above, according to the method of manufacturing a flying magnetic head according to the present invention, there is a core slider portion having a slider surface and forming one magnetic core half, and the other core slider portion having a winding groove. a magnetic core half made of a ferrite magnetic material, and a metal magnetic material is bonded to the vicinity of the magnetic gap forming portion of the other magnetic core half on a bonding surface that is non-parallel to the forming surface of the magnetic gap. In the method for manufacturing a floating magnetic head configured by
a step of forming a groove having a letter shape, a step of adhering and filling the groove with a metal magnetic material, forming the winding groove on the abutting surface, a step of mirror-finishing the abutting surface, and forming the core slider portion. a step of abutting the second ferrite block and the first block through a magnetic gap material and joining them together by glass welding; after mirror-finishing the slider surface; Since the track width is defined by forming two perpendicular parallel grooves, only one type of bonding glass is needed for the molding glass to bond the slider part and the magnetic core halves.
The metal magnetic material is bonded only to the magnetic core half, not on the slider side, and the track width is determined by the distance between the two parallel grooves. Since there is no difference in track width when butting, and since there is no glass part on the sliding surface of the recording medium, the production yield is excellent, which is advantageous in terms of cost, and it is also easy to use. This makes it possible to manufacture a floating magnetic head with high reliability.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a floating magnetic head according to the manufacturing method of the present invention, and FIG. 2 is a partially enlarged view showing the vicinity of the magnetic gap, which is the main part of the invention of the floating magnetic head shown in FIG. ,
3 to 11 are schematic explanatory views showing the manufacturing process of the floating magnetic head according to the present invention shown in FIGS. 1 and 2;
Figure 2 is a plan view showing the vicinity of the magnetic gap, Figure 13 (a)
14 is a perspective view of a conventional composite magnetic head, FIG. 14B is a plan view showing the sliding surface of the recording medium in FIG. FIG. 15(a) is a perspective view of another conventional composite magnetic head; FIG. 15(b) is a plan view showing the recording medium sliding surface of FIG. 15(a); Figures (a) and (b) are shown in Figure 15 (
FIG. 7 is an explanatory diagram for explaining the main manufacturing process of another conventional combination type magnetic head shown in FIGS. 30... Flying type magnetic head of the present invention, 31... Slider, 32... Magnetic core half, 32a... Butt surface, 33... Winding groove, 34... Magnetic gap, 35・
...Ferromagnetic metal film, 36...7-shaped groove, 36a...
Joint surface, 37...Coil, 38...Air bearing surface, 3...Slider end face, 40...Tapered groove, 41° 42...Adhesive glass. Folding 1 Diagram 13 IXT Diagram Procedural Manual (Method) % Formula % 2. Name of the invention Method for manufacturing a floating composite magnetic head 3. Relationship with the person making the amendment Patent applicant address Yokohama, Kanagawa Prefecture 3-12 Moriyamachi, Kanayo-ku, Ichi July 26, 1988 (Delivery mortar) 5. Subject of amendment Column 6: Brief explanation of the drawing of Mei 1111 Book 6. Contents of amendment

Claims (1)

[Claims] A core slider portion having a slider surface and forming one magnetic core half, and the other magnetic core half having a winding groove are made of a ferrite magnetic material, and the magnetic gap between the other magnetic core half is In a method for manufacturing a floating magnetic head in which the vicinity of the molded part is formed by bonding a metal magnetic material onto a bonding surface non-parallel to the forming surface of the magnetic gap, the abutting surface of the first ferrite block is provided. a step of forming a V-shaped groove on the core slider portion, a step of adhering and filling the groove with a metal magnetic material, forming the winding groove on the abutting surface, and mirror-finishing the abutting surface; A second ferrite block and the first block to be formed are butted together via a magnetic gap material and joined together by glass welding, and after mirror-finishing the slider surface, 1. A method for manufacturing a floating composite magnetic head, characterized in that a track width is defined by forming two substantially perpendicular parallel grooves.