JPS6151610A - Magnetic head and its manufacture - Google Patents

Abstract

PURPOSE:To decrease sufficiently a clearance between recording/reproducing gap and an erasure gap without decreasing the yield by forming the recording/reproducing gap by the 1st and 2nd cores, forming an erasure gap by the 3rd and 4th cores and forming an opening at the press contact face side of the 2nd and 3rd cores. CONSTITUTION:The 1st and 2nd cores 31, 32 are bonded, a nonmagnetic material is inserted to a slot 34 while leaving a track 35 to form the recording/reproducing gap 33 and similarly the 3rd and 4th cores 36, 37 are bonded to form the erasure gap 38. A taper face whose size 4l5 is larger than l6 is formed to the upper end face of the cores 32, 36, the taper faces are bonded and fixed while each track center of the two heads is shifted by DELTAL, and sliced, an auxiliary core 43 and coils 41, 42 are mounted to complete the magnetic head. Thus, the 2nd and 3rd cores are pressed into contact and used in common and a slope is provided to the press contact face, then the clearance between the recording/reproducing gap and the erasure gap is decreased sufficiently, the ease of manufacture is attained and the deterioration in the yield attended with the improvement of the recording density is not caused.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic head that is most suitable for recording and reproducing, for example, a magnetic disk device, and a method of manufacturing the same.

Conventional configurations and their problems Conventionally, magnetic disk drives, especially flexible disk drives, have been mainly sized with a diameter of 8 inches (approximately 2oσ) and a diameter of 5.25 inches (approximately 13 cm). 3 inches (approx. 7.5 cm) in diameter to 4 inches (approx. 1
A small flexible disk device with a diameter of 0cIn) has appeared. Generally 8 inches (approximately 20cm+L) diameter or 5.
A tunnel erase type magnetic head used for a magnetic disk with a diameter of 25 inches (approximately 13c1!) is
There is a gap of 0.8 between the recording/reproducing gap and the erasing gap.
There was a gap of more than mm, and this was corrected using an electrical circuit. If this can be reduced to 0.5 or less, the correction circuit can be made into a cylindrical element. However, in the conventional structure, this was not possible. In addition, there is a straddle erase type magnetic head with a 38% reduction in WL type magnetic head structure, but this type of magnetic head is manufactured as recording density (track density) improves.

As the process progressed, the yield rate was significantly reduced.

Here, a conventional morale head used in a flexible disk device will be explained using FIGS. 1 to 6. Figure 1 is an exploded perspective view of a tunnel erase type magnetic head for a flexible disk device, in which (1) is a recording/reproducing core (2), (3) is an erasing core for tunnel erasing, and these ( 1) to (3) are
Core members (4) to (6) and core members (7) to (
9) are bonded to glass via the magnetic gap α0-(2), and further a non-magnetic material αj~ is bonded to the core members (7)-(9).
αυ is fixed by resin adhesion or glass adhesion αe-(to). FIG. 2 is a plan view of a magnetic head constructed by assembling cores (1) to (3).

FIG. 3 is a plan view of a straddle erase type magnetic head, in which αI (1) is the first and second cores that constitute the magnetic circuit for recording and reproducing, which face each other with a magnetic gap (2) in between. ing. (22a) and (22b) are erasing cores arranged at predetermined positions with respect to the magnetic gap (2).

Fig. 4 is a perspective view of the magnetic head described in Japanese Patent Publication No. 51-9575, Fig. 5 is an enlarged plan view of the same main part, and Fig. 6 is a magnetic head described in Japanese Patent Publication No. 57-44219. FIG. 2 is a perspective view of the magnetic heads, both of which are tunnel erase type magnetic heads. In reference to Figures 4 and 5, (2)
is a common core for recording/reproducing and erasing, (c) is a recording/reproducing core, (c) is an erasing core, (e) is a recording/reproducing gap, and (b) is an erasing gap. Note that the diagonally lined portions in the figure are portions made of nonmagnetic material.

According to this, as shown in FIG.
In this case, leakage magnetic flux is generated, and the effective track width is reduced by the leakage magnetic flux shown by arrow (B). Also, in Figure 6,
(E) is the recording/reproducing gap, and the handle is the erasing gap.According to Kowa, it is the distance between the recording/reproducing gap (C) and the erasing gear 4! cannot be made smaller.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned drawbacks of the conventional art, and provides a morale head that can sufficiently reduce the distance between the recording/reproducing gap and the erasing gap without deteriorating manufacturing yield. It is an object of the present invention to provide a method for manufacturing a magnetic head that can easily manufacture this magnetic head.

Structure of the Invention In order to achieve the above object, a magnetic head of the present invention includes first and second cores forming a recording/reproducing gap, and third and fourth cores forming an erasing gap. ,
The second core and the third core have abutting surfaces that abut each other, and at least one of the abutting surfaces is provided with an inclined portion so that an opening is formed on the tape abutting surface side. It is.

Further, in the method for manufacturing a magnetic head of the present invention, the first
A recording/reproducing gap is formed by bonding the core of 3 and a second core of a substantially U-shape to each other, and a substantially I-shaped core of @3 and a fourth core of a substantially U-shape are bonded together. to form an erasing gap, and cut at least one of the mating surfaces of the second core and the third core to form an inclined part;
These abutting surfaces are adhered to each other, and an auxiliary core is further adhered across the first core and the @4 core.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below based on one drawing.

Figure 7 is a perspective view of the recording/reproducing head, where υ is the first
The core, (to) is the second core. After the first core ab is molded, the abutting surface with the second core o1) is mirror-finished. Also, the surfaces of the second cores (towards) that abut against the first six cores are mirror-finished. Next, the core 0]) (to) is bonded to glass so that the recording/reproducing gap (to) becomes a predetermined gap length. Next, grooves are processed leaving recording/reproducing tracks (34a) (34b) (34c)... with a predetermined track width, and grooves (35a) (35b) (35c) are formed.
obtain... and grooves (35a) (85b)
(85c) Non-magnetic material [e.g. core 6D (2)
A ceramic material, glass, etc. suitable for the expansion coefficient of the ferrite used is inserted to make the surface height uniform. At this time, if the expansion coefficient of the non-magnetic material is not fast cutting, resin may be filled.

FIG. 8 is a perspective view of the erasing head, in which (G) is the third core and (G) is the fourth core. After the fourth core (b) is formed, the surface that meets the third core (to) is mirror-finished. On the other hand, the abutting surface of the third core (to) with the fourth core (b) is also mirror-finished, and the cores (7) (b) are treated with glass to form a predetermined erasing gap (to). . After that, groove processing is performed to create grooves (89a) (39b) (39c).
=- and erase track (40a) (40b)
(40C)... is obtained.

Then, a non-magnetic material is inserted into the grooves (3'9a) (39b) (39c) and bonded. These operations can be performed in the same manufacturing process as the recording/reproducing head shown in FIG. 7.

Next, the abutting surface of the second core (goods) with the erasing head is mirror-finished, and the grooves (35a) (35
b) When the depth of (35c)... is 12! 3
<14, and if the thickness of the second core (toward) is 16, then 16≦41. A sloped portion (hereinafter referred to as a taper) is provided so that the Similarly, the surface of the third core (to) that abuts against the second core (to) is mirror-finished and provided with a taper.

Further, as shown in FIG. 10, the recording/reproducing head section and the erasing head section are adhesively fixed with resin. The adhesion position at this time is set at a position where the track center of the recording/reproducing head section and the track center of the erasing head section are shifted by ΔL, as shown in FIG.

The dimension of this ΔL varies depending on the diameter of the flexible disk used. Next, the bottom part is milled to give it a mirror finish.

After that, as shown in Figure 12, the dashed-dotted lines (A), (B), (C)...
The head chip part is completed by cutting at the position. This head chip has a recording/playback coil (
41J and the erasing coil (6). When inserting the coils, as shown in FIG. 15, the recording/reproducing coil is inserted into the first core Gη, and the erasing coil (6) is inserted into the fourth core (2). Next, a mirror-finished auxiliary core shown in FIG. 13 is adhesively fixed to form a closed magnetic path, and the magnetic head is completed as shown in FIG. 16.

In this way, since the second core 6, which forms the recording/reproducing gap, and the third core, which forms the erasing gap, are shared, the gap distance can be set to Q, 5 mm or less. At the same time, magnetic saturation of the core can be eliminated. In addition, the magnetic flux generated by the erasing coil (6)
The stagnation from the fourth core (b) to the second core 0 and the leakage magnetic flux that reduces the track width are shown in Fig. 14 and 1.
As shown in Figure 5, the second core 0 and the third core (to)
Due to the taper provided on the abutting surface, the distance between the fourth core height and the second core Q can be increased by 215, thereby reducing the distance. Therefore, the distance between the recording/reproducing gap (to) and the erasing gap (to) can be reduced by that amount, and can actually be reduced to 0.5 or less. In addition, there is an interval of 265 mm between the recording/reproducing magnetic circuit and the erasing magnetic circuit at the gap portion, and as shown in FIG. The resistance becomes large, and the recording/reproducing coil 0]
), and their interference can be prevented. Furthermore, depending on the size of the medium, conventionally the recording/reproducing core 61) was set at a small angle (azimuth), but in the magnetic head of this embodiment, the erase This can be dealt with by shifting the center line of the track by ΔL. Further, according to the manufacturing method of this embodiment, all processing is performed with mechanical precision, so the work is stable and manufacturing is easy.

In the above embodiment, an example was described in which a taper was provided on both of the abutting surfaces of the second core wire and the third core (end), but the taper may be provided on only one of them. .

As described in detail of the invention, according to the magnetic spatula bottom according to the present invention, the second core of the recording/reproducing magnetic circuit and the third core of the erasing magnetic circuit are brought into contact with each other for common use. However, in order to eliminate the feedthrough that occurs due to this, a sloped portion is provided on the abutting surface of the second core and the third core, so that the gap between the recording/reproducing gap and the erasing gap is sufficiently spaced. The correction circuit can be simplified. Further, according to the method for manufacturing a magnetic head according to the present invention, the above-mentioned magnetic head can be easily manufactured, and there is no deterioration in yield due to improvement in recording density.

[Brief Description of the Drawings] Fig. 1 is an exploded perspective view of a conventional tunnel erase type magnetic head, Fig. 2 is a plan view thereof, Fig. 3 is a plan view of a conventional straddle erase type magnetic head, and Fig. 4 is an exploded perspective view of a conventional tunnel erase type magnetic head. The figure is a perspective view of another conventional tunnel erase type magnetic head, FIG. 5 is an enlarged plan view of the same, and FIG. 6 is a perspective view of another conventional tunnel erase type magnetic head. FIG. 7 is a perspective view of a recording/reproducing magnetic circuit in an embodiment of the present invention after track processing and a non-magnetic material is bonded to it, and FIG. 8 is a track processing of an erasing magnetic circuit in an embodiment of the present invention. FIG. 9 is a perspective view of the state in which the non-magnetic material is adhered, and FIG.
Figure 0 is a perspective view of the recording/reproducing core and erasing core bonded together and the back side processed, Figure 11 is an explanatory diagram of the misalignment of the recording/reproducing head with the track center, and Figure 12 is 13 is a perspective view of the auxiliary core, and FIG. 14 is a plan view of the main parts of the magnetic head in one embodiment of the present invention. , 1st
FIG. 5 is an explanatory diagram of the magnetic path of the magnetic head, and FIG. 16 is a perspective view of the magnetic head. C31)...first core, G...second core, a
...recording/playback gap, (to)...third core, (b)...fourth core, (to)...erasing gap, (foundation)...auxiliary core substitute Yoshihiro Morimoto Figure 1 Figure 2 @ Figure 3 Figure 4 Figure 5 Figure 5 Figure 7 Figure 8 Figure 9 Figure π Figure 1f Figure 12

Claims (1)

[Claims] 1. First and second cores forming a recording/reproducing gap, and third and fourth cores forming an erasing gap, the second core and the third core forming a gap for erasing. The core has abutting surfaces that abut each other, and at least one of the abutting surfaces,
A magnetic head that has a sloped portion so that an opening is formed on the tape contacting surface. 2. The magnetic head according to claim 1, wherein the inclined portion is provided only on the second core. 3. The magnetic head according to claim 1, wherein the inclined portion is provided only on the third core. 4. The magnetic head according to claim 1, wherein the inclined portion is provided on both the second core and the third core. 5. The magnetic head according to any one of claims 1 to 4, wherein the recording/reproducing gap and the erasing gap are configured so that their track centers are shifted from each other. 6. A substantially U-shaped first core and a substantially I-shaped second core are bonded to each other to form a recording/reproducing gap, and a substantially I-shaped third core and a substantially U-shaped third core are bonded to each other. an erase gap is formed by bonding a fourth core of
After cutting at least one of the abutting surfaces with the core to form an inclined part, these abutting surfaces are bonded to each other, and an auxiliary core is further bonded across the first core and the fourth core. A method of manufacturing a magnetic head.