JPH09293205A - Magnetic head - Google Patents

Abstract

(57) An object of the present invention is to provide a magnetic head in which the flow of magnetic flux in the lower part of the core is not obstructed. SOLUTION: A pair of core halves 11 and 12 are butted against each other and joined to define a gap portion 17, and the gap portion is defined by the track width regulating groove 11b provided in each core half body. In the magnetic head 10, the track width regulating grooves 11b and 12b are formed so as to have a predetermined track width by the groove 12b, and the region of the tape sliding surface near the gap is step processed in the track width direction. However, the magnetic head 10 is configured so that the size is selected so that the core half body is accommodated within the thickness of the non-step processed portion.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a video tape recorder (VTR), a digital video cassette (DV), and the like.
C) for video, audio for digital audio tape recorder (DAT), etc. or DDS for computer etc.
The present invention relates to a magnetic head used in a magnetic recording / reproducing device for (digital data storage).

[0002]

2. Description of the Related Art Conventionally, such a magnetic head has been used for MIG.
A (metal-in-gap) type magnetic head is constructed, for example, as shown in FIG. That is, in FIG. 6, the magnetic head 1 is composed of a pair of core halves 2 and 3 made of Mn—Zn ferrite or the like, and the abutting surfaces (joining surfaces) of the core halves 2 and 3 are respectively formed. For example, after the metal magnetic films 2a and 3a made of Fe-Al-Si alloy are formed, they are bonded to each other by the adhesive glass 4, and the coil winding portions 2b and 3b are provided with recording / reproducing coils (not shown). Is wound.

A gap member 6 is formed between the abutting surfaces of the core halves 2 and 3 by inserting a gap member 5 therebetween. Further, the upper surfaces of the core halves 2 and 3 maintain the adhesion to the magnetic tape (not shown) and the mechanical strength of the entire core, so that the thickness of the entire core is not changed and only the sliding surface is used. Step portions 7 and 8 are formed by step processing from both sides so as to form a tape sliding surface having a width wider than the track width of the gap portion 6.

Here, the magnetic head 1 is manufactured as shown in FIGS. That is,
First, in FIG. 7, winding grooves (coil winding portions) 2b, 3b
Are formed, a plurality of core base materials 2 and 3 made of a ceramic material such as a ceramic having a C-shaped cross section, glass ceramics, and the like are formed on the abutting surface and extend in the vertical direction adjacent to each other in the longitudinal direction. After the track width regulation grooves 2c and 3c of the book are formed, the metal magnetic films 2a and 3a are formed on the abutting surfaces.

From this state, both core base materials 2 and 3 are
As shown in FIG. 8, they are bonded to each other by the bonding glass 4. At this time, the bonding glass 4 is also filled in the track width regulating grooves 2c and 3c.

Further, the core base materials 2 and 3 joined to each other
As shown in FIG. 9, the upper surface of the track width regulating groove 2
a plurality of step grooves 7, 8 corresponding to the pitches c, 3c
Are processed so as to extend in a direction orthogonal to the abutting surfaces of the core base materials 2 and 3, whereby the track width regulating groove 2
The tape sliding surface is defined so as to sandwich the region of the gap portion 6 formed between c and 3c.

Finally, the core base materials 2 and 3 are sliced in parallel with the step grooves 7 and 8 so as to have a predetermined core chip thickness, whereby the magnetic head 1 shown in FIG. 6 is completed. ing.

[0008]

However, in the magnetic head 1 thus constructed, as shown in FIG. 6, the track width regulating grooves 2c and 3c are formed from the tape sliding surface at the upper end to the core half body 2. , 3 to the lower portion, that is, the portion including the winding groove forming the coil winding portion, is processed with a constant groove depth. Therefore, the abutting surface of the lower core below the bottom surface of the winding groove is joined only with the same width as the track width in the gap portion 6, so that the joining cross-sectional area is reduced, and the core 2 and the lower core 3 are joined together. Since the flow of the magnetic flux of the magnetic tape is obstructed, the efficiency is reduced, a larger current is required for recording on the magnetic tape, and the output current is reduced for reproducing. Become.

On the other hand, since the track width of the magnetic head in recent DVC, DDS, etc. is about 10 μm, when the core halves 2 and 3 are joined, the tape sliding surface side is used as a reference. As the track alignment is performed, if there is a track shift in the lower part of the core due to a shift in the squareness of the track width regulation grooves 2c and 3c, the above-mentioned decrease in efficiency becomes more remarkable, so that the magnetic head 1 is mass-produced. There are many variations in the recording and reproducing characteristics of the head,
There is a problem that the yield is reduced.

In view of the above points, it is an object of the present invention to provide a magnetic head in which the flow of magnetic flux under the core is not obstructed.

[0011]

According to the present invention, the above-mentioned object is to define a gap portion by abutting and joining a pair of core halves to each other. Due to the track width regulation groove provided on the body,
In a magnetic head configured to have a predetermined track width, and further, a region of the tape sliding surface near the gap portion is step processed in the track width direction,
This is achieved by a magnetic head characterized in that the track width regulating groove is sized so as to be within the thickness of the non-stepped portion of each core half.

According to the above construction, the track width restricting groove of the core half is within the thickness of the portion of each core half that is not step processed, so that the lower part of the core half below the bottom of the winding groove is butted. The joining cross-sectional area in the plane becomes large.
This does not hinder the flow of magnetic flux between the core halves in the lower part of the core. Therefore, the efficiency does not decrease, a smaller current is required for recording on the magnetic tape, and a decrease in output current can be suppressed for reproducing. For example, the track width is 10 μm
Even in such a case, the variation in the recording / reproducing characteristics of the magnetic head during mass production is reduced, and the yield is improved.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings. FIG. 1 shows an embodiment of a magnetic head according to the present invention. In FIG. 1, a magnetic head 10 is composed of a pair of core halves 11 and 12 made of Mn-Zn ferrite or the like, and the abutting surfaces of the core halves 11 and 12 are each made of, for example, Fe-Al-Si. After the metal magnetic films 13 and 14 made of an alloy are formed, they are bonded to each other by the adhesive glass 15 and the winding grooves 11a and 1 that form the coil winding portion thereof.
A recording / reproducing coil (not shown) is wound around 2a.

Here, the gap member 16 is inserted between the abutting surfaces of the core halves 11 and 12, whereby
The gap portion 17 is formed. Furthermore, core half 1
The upper surfaces of 1 and 12 maintain the adhesion to the magnetic tape (not shown) and the mechanical strength of the entire core.
Steps 18 and 19 are formed by step processing from both sides only on the sliding surface without changing the thickness of the entire core.

The above-mentioned structure is almost the same as the conventional magnetic head 1 shown in FIG. 6, but in the magnetic head 10 according to the embodiment of the present invention, in order to regulate the track width of the gap portion 17, In the region of the gap portion 17, the track width regulating grooves 11b and 12b formed on the side surfaces of the core halves 11 and 12 are the winding grooves 11 of the core halves 11 and 12.
a, 12a below the bottom of the core, the core half 11,
It is formed so as to fit within the core thickness without being exposed on the surface of 12.

Here, the magnetic head 10 is manufactured as shown in FIGS. That is, first, in FIG. 2, the core base material 20 to form the core halves 11 and 12 has a winding guide 21, a reinforcing groove 22, and a winding groove 23 (11a, 12a) formed along the longitudinal direction. After that, a plurality of track width regulating grooves 24 (11b, 12b) adjacent to each other in the longitudinal direction and extending in the vertical direction in FIG.

Then, as shown in FIG. 3, the pair of core base materials 20 (core halves 11 and 12) have metal magnetic films 13 and 14 formed on their abutting surfaces.

From this state, both core base materials 11 and 12 are
Are bonded to each other by a bonding glass 15, as shown in FIG. At this time, the bonding glass 15 is also filled in the track width regulating groove 24.

Further, the core base materials 11 joined to each other,
As shown in FIGS. 4 and 5, the upper surface of 12 includes a plurality of step grooves 2 corresponding to the pitch of the track width restricting grooves 24 along the line L including the two track width restricting grooves 24.
The tapes 5 and 26 are processed so as to extend in a direction orthogonal to the abutting surfaces of the core preforms 11 and 12, so that the area of the gap portion 17 formed between the track width regulating grooves 24 is sandwiched between the tapes 5 and 26. A sliding surface is defined.

Finally, the core base materials 11 and 12 are sliced in parallel with the step grooves 25 and 26 so as to have a predetermined core chip thickness, so that the magnetic head 10 of FIG.
Is to be completed.

The magnetic head 10 manufactured according to the embodiment of the present invention is configured as described above, and the gap portion 1
7 can be defined by the joining surfaces of the core halves 11, 12. As a result, the magnetic tape (not shown) slides along the tape sliding surface formed on the upper surfaces of the core halves 11 and 12 of the magnetic head 10 by step processing, and The magnetically recorded data or the like can be converted into an electric signal by the coil winding and can be reproduced.

In this case, in the magnetic head 10, the track width regulating grooves 11b and 12b formed before the joining of the core halves 11 and 12 are made relatively small as shown in FIG. Therefore, the track width regulating grooves 11b and 12b of the core halves 11 and 12 are
It fits within the thickness of the part that is not processed in step 2. Therefore, the lower butting surfaces of the core halves 11 and 12 below the bottoms of the winding grooves 11a and 12a are not only in the central portion corresponding to the gap portion 17 but also in the portions on both sides indicated by reference characters a and b in FIG. Since they can be bonded to each other, the bonding cross-sectional area is increased.

Thus, the flow of the magnetic flux between the core halves 11 and 12 at the lower part of the core halves 11 and 12 is not obstructed, and the decrease in efficiency can be suppressed. As a result, a smaller current can be used when recording on the magnetic tape, and a decrease in output current can be suppressed when reproducing.

Further, for example, even when the track width is about 10 μm, a relatively large junction cross-sectional area at the lower portions of the core halves 11 and 12 can be secured, so that the recording / reproducing characteristics of the magnetic head during mass production can be improved. Variation is reduced and yield is improved.

[0025]

As described above, according to the present invention, the track width regulating groove of the core half is contained within the thickness of the portion of the core which is not step-processed. The joining cross-sectional area at the butt surface of the lower part of the body is increased. This does not hinder the flow of magnetic flux between the core halves in the lower part of the core. Therefore, the efficiency does not decrease, a smaller current is required for recording on the magnetic tape, and a decrease in output current can be suppressed for reproducing. For example, even when the track width is about 10 μm, the variation in the recording / reproducing characteristics of the magnetic head during mass production is reduced, and the yield is improved.

Thus, according to the present invention, it is possible to provide an extremely excellent magnetic head in which the flow of magnetic flux under the core is not obstructed.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an embodiment of a magnetic head according to the present invention.

FIG. 2 is a schematic view showing a track width regulating groove processing step in the manufacturing process of the magnetic head of FIG.

FIG. 3 is a schematic diagram showing a butting process in a manufacturing process of the magnetic head of FIG.

FIG. 4 is a schematic view showing a glass bonding step in the manufacturing process of the magnetic head of FIG.

5 is a schematic diagram showing a step groove processing step in the manufacturing process of the magnetic head of FIG. 1. FIG.

FIG. 6 is a schematic perspective view showing an example of a conventional magnetic head.

FIG. 7 is a schematic view showing a butting step in the manufacturing process of the magnetic head of FIG.

FIG. 8 is a schematic view showing a glass bonding step in the manufacturing process of the magnetic head of FIG.

9 is a schematic diagram showing a step groove processing step in the manufacturing process of the magnetic head of FIG.

[Explanation of symbols]

 10 magnetic head 11 and 12 core half body 11a, 12a and 23 winding groove 11b, 12b and 24 track width regulation groove 13 and 14 metal magnetic film 15 bonding glass 16 gap material 17 gap part 18 and 19 step part 20 core base material 21 winding guide 22 reinforcing groove

Claims (2)

[Claims] 1. A gap portion is defined by abutting and joining a pair of core halves to each other, and the gap portion is defined by a track width regulating groove provided in each core half body for a predetermined track. In the magnetic head, which is configured to have a width, and the region of the tape sliding surface near the gap portion is step-processed in the track width direction, the track width regulation groove is not step-processed in each core half body. A magnetic head, characterized in that the size is selected so that the size is within the thickness of the portion. 2. The magnetic head according to claim 1, wherein a metal magnetic film is formed on the abutting surfaces of the pair of core halves.