JPS63288408A - Production of composite magnetic head - Google Patents

Abstract

PURPOSE:To improve the wear resistance and the track width accuracy by fusing and filling mold glass in a groove preliminarily formed for track width control on a block consisting of an oxide magnetic material. CONSTITUTION:Magnetic core half bodies 31 and 31' are allowed to abut each other so that a metallic magnetic film 33, an oxide magnetic material 34, and an oxide magnetic material 34' face a metallic magnetic film 33', a nonmagnetic material 32', and a nonmagnetic material 32 respectively, and they are joined into one body. Mold glass 39 and 39; having a high melting point are filled in grooves 37 and 37' for track width control which are formed in abutting parts of oxide magnetic materials 34 and 34' and are used to form a main magnetic path on a tape slide face 38 of a magnetic core main body 30 by metallic magnetic films 33 and 33'. Consequently, metallic magnetic films can be formed on a nonmagnetic substrate whose coefficient of thermal expansion is matched to metallic magnetic films, and peeling and the degradation in magnetic characteristic of metallic magnetic films 33 and 33' due to thermal stress are prevented. Thus, the wear resistance and the track width accuracy are improved.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a magnetic recording/reproducing device, particularly a composite magnetic head suitable as a magnetic head for high-density recording/reproducing of a video tape recorder, a rotary digital audio recorder, etc. Relating to a manufacturing method.

(Conventional examples and their problems) Metal tapes with high coercive force are widely used as recording media such as magnetic tapes in order to improve the performance and miniaturize magnetic recording and reproducing devices. Research and development of magnetic heads for use with magnetic tapes having such high coercive force is progressing.

As such magnetic heads, so-called composite magnetic heads have been realized, in which a magnetic core body is made by combining a metal-based magnetic material with a high saturation magnetic flux density and an oxide-based magnetic material with excellent high-frequency characteristics.

FIG. 13 shows a magnetic core body 10 of a conventional composite magnetic head.
FIG. In the figure, 11.12 is [n-core half body, such as Sendust (registered trademark), amorphous,
Both surfaces of metal magnetic materials 13 and 14 such as permalloy are sandwiched and joined together by oxide magnetic materials 15, 16 and 17, 18 such as Mn-7n ferrite and Ni-7n ferrite, respectively. and the opposing abutting surfaces 11a.

A winding window 19 is formed on at least one of the magnetic core halves 12a, for example on the abutting surface 11a side as shown, and the pair of magnetic core halves 11.12 are abutted and integrally joined via a gap material such as 5i02. A magnetic gap 20 is formed. Reference numerals 22 and 23 indicate track width regulating grooves for regulating the width of the magnetic gap 20 on the tape sliding surface 21 to a predetermined track width. Molded glass 24.
25 is melt-filled.

However, the thermal expansion coefficients of the oxide-based magnetic material and the metal-based magnetic material are significantly different, and when a metal-based magnetic film is formed on a flat surface of the oxide-based magnetic material, this metal-based magnetic film may peel off considerably. Therefore, in the composite magnetic head 10, a thin film 1 made of a metallic magnetic material wrapped in advance to a track width thickness is used.
3.14 is used, but not only is it very troublesome to wrap the metal magnetic material to the track width thickness, but this thin plate 13.14 is very thin and is brittle and easily broken, which reduces productivity. was bad. In addition, since the track width regulating grooves 22 and 23 are formed on both sides of the magnetic gap 20, the accuracy of the track width is very good, and when the plate is erroneously cut into the thin plate 13.1 during the grooving process.
4, there was a risk that the thin plates 13 and 14 in the same area would fly off, resulting in poor productivity.

For this reason, although not shown, a metal-based magnetic film is formed on the abutting portion of a pair of magnetic core halves made of an oxide-based magnetic material, and a magnetic gap is formed by abutting the pair of magnetic core halves. Some composite magnetic heads are available in which molded glass is fused and filled on both sides of the magnetic gap, but in all of these, a V-groove is formed in a block made of an oxide-based magnetic material, and a metal-based magnetic head is formed in the V-groove. Since a magnetic film is formed, there are problems such as the V-groove machining operation is extremely troublesome and mass production is poor.

(Means for Solving the Problems) The present invention has been made to solve the above problems, and includes forming a metal-based magnetic film on a non-magnetic substrate made of crystallized glass or ceramic by a thin film forming means. Process: Form multiple grooves in a block made of oxide-based magnetic material,
a step of melting and filling mold glass into the groove; a step of cutting the block filled with the mold glass along a cutting line parallel to the reference plane to obtain a composite substrate; and forming the metal-based magnetic film. Non-magnetic substrates and composite substrates are alternately laminated via bonding glass and bonded together.
a step of obtaining a laminated block; a step of cutting the laminated block along a cutting line perpendicular to a reference plane and passing through the end of a groove filled with molded glass to obtain a magnetic core half block; a pair of magnetic cores; At the butt part of the half block,
Obtaining a magnetic core block by abutting and joining the metal-based magnetic films and the composite substrate and the non-magnetic substrate facing each other through a gap material to obtain a magnetic core block; The present invention provides a method for manufacturing a composite magnetic head, comprising the step of cutting along a cutting line parallel to the magnetic core to obtain a magnetic core body.

(Example) FIG. 1 is a perspective view showing a magnetic core body 30 of a composite magnetic head manufactured by the manufacturing method according to the present invention.
FIG. 2 is a partially enlarged plan view of the tape ephemeris motion surface near the magnetic gap of the magnetic core body 30 shown in FIG. In FIGS. 1 and 2, 31 and 31- are magnetic core halves, and the metal-based magnetic B133.33- made of sendust or amorphous, for example, has approximately the same wear resistance characteristics as the oxide film-based magnetic material described later. A non-magnetic material 32,32' made of crystallized glass or ceramic and, for example, Mn-
Oxide-based magnetic material made of 7n ferrite etc. 34.34-
A winding groove 35 is formed on at least one of the opposing abutting surfaces 31a and 31a, for example, on the abutting surface 31a side as shown in the figure, and the pair of magnetic core halves are The body 31.31=,
For example, the metal magnetic film 33-, the oxide magnetic material 34 and the non-magnetic material 32-1, the oxide-based magnetic material 34- and the non-magnetic material 32 are connected to each other through a gap material such as 5i02. A magnetic core main body 30 having a magnetic gap 36 is formed by abutting the magnetic cores so as to face each other and joining them together. 37.37'' is a metal-based magnetic film that connects the main magnetic path on the tape sliding surface 38 of the magnetic core body 30 formed at the abutting portion of the oxide-based magnetic material 34, 34- of the magnetic core half body 31.31=. The track width regulating groove is filled with, for example, high melting point molded glass 39,39'.

Reference numeral 40 denotes adhesive glass that is melted and filled into a part of the winding groove 35 in order to join the magnetic core halves 31 and 31- together.

As described above, according to the composite magnetic head of the present invention, the molded glass 39. exposed on the tape sliding surface 38.
The area of 39' is half of the conventional magnetic core body 10,
Moreover, they are arranged in a well-balanced manner in a symmetrical position across the magnetic gap 36, and the wear characteristics of the non-magnetic material 32.32'' can be easily selected from those of the oxide-based magnetic material 34.34'. This enables a composite magnetic head with excellent wear resistance and less uneven wear.

Next, a method of manufacturing the magnetic core body 30 shown in FIG. 1 will be described.

3 to 11 are schematic illustrations of the main steps of the method for manufacturing the magnetic core body 30 shown in FIG. 1.

In the figure, the same materials and the same components used in the magnetic core body 30 shown in FIG.

In the first step, as shown in FIG. 3(a), a plurality of plate-shaped non-magnetic materials 32 made of crystallized glass or ceramic were prepared, and both sides of these non-magnetic materials 32 were polished to a mirror finish. Afterwards, metal-based magnetic material 11133 made of sendust, amorphous, etc., is applied to one surface of the polished surface as shown in FIG.
is formed by thin plate forming means such as sputtering, vapor deposition, and ion blating. At this time, metal magnetism! 13
Let t be the thickness of the non-magnetic material 32 on which 3 is formed. These non-magnetic materials 32 are metal-based magnetic materials used at this time! The material is selected from among non-magnetic materials having approximately the same coefficient of thermal expansion as No. 133 and approximately the same wear resistance properties as the oxide-based magnetic film 34 described later.

In the second step, for example, a block-shaped oxide-based magnetic material 34 made of Mn-7n ferrite is prepared (Fig. 4).
Grooves 37 perpendicular to the reference surface 34a are formed on one surface 34b of this oxide-based magnetic material 34 at a pitch substantially equal to the width W of the magnetic core halves 31.degree. 31-, as shown in FIG.

In the third step, as shown in FIG. 6, molded glass 39 with a high melting point and excellent wear resistance is melted and filled into the grooves 37 formed in the second step, and then the excess molded glass is removed by polishing, etc. Remove by.

In the fourth step, the oxide-based magnetic material 34 is cut at a pitch along cutting lines 50 parallel to the reference plane 34a, and the composite substrate 5
Get 1. (FIG. 7) In the step 5-f#, the non-magnetic material 32 on which the metallic magnetic film 33 was formed in the first step and the composite substrate 51 are alternately laminated with bonding glass interposed therebetween, and then processed. The laminated block 52 is obtained by joining together by applying pressure and heating. (FIG. 8) In the sixth step, the laminated block 52 obtained in the fifth step is cut along cutting lines 53 having a pitch W passing through the grooves 37 to form a pair of block-shaped magnetic core halves 31. 31
− etc. are obtained. (FIG. 9) In the seventh step, the mold glass 37 side of the cut surfaces of the pair of magnetic core halves 31, 31- obtained in the sixth step is made into an abutting surface 318, 318-,
At least one of the abutting surfaces 31a, 31a-, for example, as shown in FIG. 10, a winding groove 35 is formed in the longitudinal direction of the abutting surface 31a of one of the magnetic core halves 31, 31a - is polished to a mirror surface.

In the eighth step, the other magnetic core half 31' is rotated 180 degrees, and a metallic magnetic material [13
3, 33- are facing each other and bonded glass 4.
After joining together using 0 etc., metallic magnetic 11!3
By cutting along the cutting line 54 parallel to 3.33', the magnetic core body 30 shown in FIG. 1 before tip polishing can be obtained. (FIG. 11) Next, a method of manufacturing the magnetic core body 30 shown in FIGS. 1 and 2 in which the magnetic gap 36 has an azimuth angle θ will be described.

Since the manufacturing process is roughly similar to the manufacturing process of the previous embodiment, the same components are given the same reference numerals, and only the different points will be explained.

FIGS. 12(a) to 12(C) are diagrams for explaining the paradoxical process when the magnetic core main body 30 shown in FIGS. 1 and 2 has an azimuth angle θ, and will be explained below using the same diagrams. do.

Oxide-based magnetic material 340 surface 34b in the second step
at a pitch substantially equal to the width W of the magnetic core half body 31.31', and perpendicular to the reference surface 34a I! The groove 37 is formed to have an inclination angle of θ with respect to the groove 60.

In the fourth step, as shown in FIG. 12(b),
The oxide-based magnetic material 34 is cut along cutting lines 50 that are parallel to the reference plane 34a and have approximately the same pitch as the thickness t of the non-magnetic material 32 on which the metal-based magnetic film 33 is formed.
1, and among these composite substrates 51, FIG. 12 (
As shown in b), the odd-numbered (or even-numbered) composite substrate 51 is replaced with a non-magnetic material 32 on which a metal-based magnetic film 33 is formed, the bonding layer is laminated with glass interposed therebetween, and 37 is cut l!
Laminated blocks 52 aligned in a straight line along 53 are obtained.

Thereafter, the magnetic core body 30 having the azimuth angle θ can be obtained by the sixth to eighth steps.

(Effects of the Invention) According to the manufacturing method of the present invention, the metal-based magnetic film can be formed on a non-magnetic substrate whose coefficient of thermal expansion matches that of the metal-based magnetic film. No peeling or deterioration of magnetic properties will occur. In addition, grooves for track width regulation were formed in advance on the block made of oxide-based magnetic material, and molded glass was melted and filled into these grooves, so there was no need to process track width regulation grooves for each magnetic head. As a result, the track width accuracy is improved and high melting point glass can be used as the mold glass, making it possible to provide a composite magnetic head with excellent wear resistance and high reliability.

In addition, there is no risk of the metal-based magnetic film being destroyed unlike in the past.
It is possible to improve yield and mass productivity.

Further, the manufacturing method of the present invention has a feature that it is possible to easily manufacture a composite magnetic head having an azimuth angle.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a magnetic core body of a composite magnetic head manufactured by the manufacturing method of the present invention, and FIG. 2 is a view of a tape sliding surface near the magnetic gap of the magnetic core body shown in FIG. Enlarged plan view of the section, Figures 3 to 11 are the 1st
12 (a) to (c) are schematic explanatory diagrams of the main steps for explaining the manufacturing method of the magnetic core body shown in the figure. The magnetic core body shown in Figures 1 and 2 has an azimuth angle θ. FIG. 13 is a perspective view showing a core body of a conventional composite magnetic head. 30...Magnetic core body, 31.31''...Magnetic core half body, 32.32-...Non-magnetic material, 33.33--
...Metal magnetic film, 34.34'...Oxide magnetic material, 34a...Reference surface, 34b...Grooved surface, 35.
・Winding groove, 36...Magnetic gap, 37.37-・
...Groove, 38...Tape sliding surface, 39.39"...
Molded glass, 51... Composite substrate, 52... Laminated block, 60... Perpendicular to the reference plane.

Claims (2)

[Claims] (1) A step of forming a metal-based magnetic film on a non-magnetic substrate made of crystallized glass or ceramic by a thin film forming means, forming a plurality of grooves in a block made of an oxide-based magnetic material,
a step of melting and filling mold glass into the groove; a step of cutting the block filled with the mold glass along a cutting line parallel to the reference plane to obtain a composite substrate; and forming the metal-based magnetic film. Non-magnetic substrates and composite substrates are alternately laminated via bonding glass and bonded together.
a step of obtaining a laminated block; a step of cutting the laminated block along a cutting line perpendicular to the reference plane and passing through the end of the groove filled with molded glass to obtain a magnetic core half block; a pair of magnetic cores; Obtaining a magnetic core block by abutting and joining the half blocks integrally to the abutting portions of the half blocks through a gap material so that the metal-based magnetic films and the composite substrate and the non-magnetic substrate face each other; A method for manufacturing a composite magnetic head, comprising the step of cutting a magnetic core block along cutting lines parallel to a metal magnetic film to obtain a magnetic core body. (2) A step of forming a metal-based magnetic film by thin film means on a non-magnetic substrate made of crystallized glass or ceramic, in which a block made of oxide-based magnetic material is made at an inclination angle equal to the azimuth angle with respect to the reference plane. forming a plurality of grooves and melting and filling molded glass into these grooves, placing the block filled with the molded glass parallel to the reference plane and on the non-magnetic substrate on which the metallic magnetic film is formed; A composite substrate is obtained by cutting along cutting lines with a pitch that is approximately the same as the thickness, and the odd numbered (or even numbered) composite substrate is replaced with a nonmagnetic substrate on which a metal magnetic film is formed, and the bonding glass is a step of stacking the stacked blocks through a groove and joining them together to obtain a stacked block; passing the stacked block through the groove filled with the molded glass, and passing the edge of the groove parallel to the inclination angle of the groove and filled with the molded glass; A step of cutting the pair of magnetic core half blocks along a cutting line passing through the magnetic core half blocks, and cutting the pair of magnetic core half blocks at the abutting portions with a gap material between them and between the metal-based magnetic films, the composite substrate, and the nonmagnetic substrate. a step of butting and joining them together so that they face each other to obtain a magnetic core block, and a step of cutting the magnetic core block along cutting lines parallel to the metal-based magnetic film to obtain a magnetic core body. A manufacturing method for a featured composite magnetic head.