JP2005135475A - Magnetic head and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetic head for maintaining high performance for a long period in which machining efficiency is high and defective articles are not produced by setting a track width precisely. <P>SOLUTION: A pair of core half bodies 5A, 5B made of a magnetic material in which an inner surface 5b is inclined at a specified azimuth angle θ is used. The inner surfaces 5b that face each other of both the core half bodies 5A, 5B are joined by a nonmagnetic joining material 10 while sandwiching a magnetic gap G for forming a magnetic head core 5. A pair of notched grooves 12 is formed along the entire length L of the magnetic head core 5 at both the side edges of the front surface of the magnetic head core 5, thus allowing a track formation surface T in parallel with a track scanning direction X to remain unnotched between both the notched grooves 12. Curved machining is made to the front surface of the magnetic head core 5, thus forming a magnetic tape sliding surface C so that the center section of the notched grooves 12 remains and both the end sections of the notched groove 12 are eliminated. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a magnetic head attached to a cylinder head of a magnetic tape device, for example, and a method for manufacturing the same. In particular, the track width of a magnetic head core for two heads is precisely set, the processing efficiency is high, and no defective product is generated over a long period. It is designed to maintain high performance.

Conventionally, as a magnetic head technology, there is one described in Patent Document 1 or the like, which includes FIG.
A recording / reproducing magnetic head 1a and a Hi-Fi magnetic head 1b provided in a four-head Hi-Fi type (4HD) cylinder head 2 shown in FIG. 4A, and a two-head type (2HD) shown in FIG. There are three types of magnetic heads 1 (1a to 1c) including a recording / reproducing magnetic head 1c provided on the cylinder head 2.

As shown in FIG. 5, the magnetic head core 5 forming each magnetic head 1 has a magnetic surface in which the outer surface 5a is formed in a direction perpendicular to the track scanning direction X and the inner surface 5b is inclined at a predetermined azimuth angle θ. A pair of core halves 5A and 5B are formed, and a winding window 6 and a joint window 7 are formed on both core halves 5A and 5B, and inner side surfaces 5b of both core halves 5A and 5B On both sides of the front surfaces of both core halves 5A and 5B.
In addition, by forming a pair of notch grooves 8 with the magnetic gap G interposed therebetween, a track forming surface T having a predetermined track t width is formed between the notch grooves 8, for example, glass, ceramic, synthetic resin The core halves 5A, 5 are filled by filling each notch groove 8 with a filler 9 made of a nonmagnetic material such as the above, and filling the joint window 7 with a joint material 10 also made of a nonmagnetic material.
B are joined with a magnetic gap G interposed therebetween, and a magnetic tape sliding surface C is formed by subjecting the front surfaces of both fillers 9 and both core halves 5A and 5B to a curved surface. By relatively running a magnetic tape (not shown) along C, recording and reproduction are performed on the magnetic tape.

As shown on the right side of FIG. 6, the world color television broadcasting system using the magnetic heads 1 includes the NTSC system having a magnetic gap G width of about 0.4 ± 0.05 μm and the magnetic gap G width of 0. There is a PAL method of about .47 ± 0.05 μm, and the magnetic head 1 is roughly divided into five types.

As shown on the left side of FIG. 6, the five types of magnetic heads 1 are divided into 10 types (A to J) according to the difference in the track t width, and 6 types of the 10 types of magnetic heads 1 are included. Things (C, F, G, H, I, J) are divided into two types (R, L) according to the left and right direction of the azimuth angle, and the magnetic head 1 is divided into 16 types after all. LP indicates one speed and SP indicates two speed.

The method of manufacturing each magnetic head 1 will be described. In the first step, as shown in FIG.
For example, a pair of core bar halves 5Aa and 5Bb made of a magnetic material such as a high permeability ferrite, a sendust alloy, or a laminated body of amorphous magnetic alloy bands, and a groove 6a for the winding window 6 and a groove 7 for the bonding window 7 are provided.
By recessing a, five types of core bar halves 5Aa and 5Bb with a pair of concave grooves 6a and 7a are formed in accordance with the five types of magnetic head 1 shown on the right side of FIG.

In the second step, as shown in FIG. 7 (b), the core bar half body 5A with five types of concave grooves 6a and 7a is provided.
A plurality of notch grooves 8 are formed on the edges of a and 5Bb in accordance with the track t width to form 10 types of core bar halves 5Aa and 5Bb with a pair of notch grooves 8 (A to J in FIG. 6). After that, the inner surface 5b facing each other of the core bar halves 5Aa and 5Bb with the notch grooves 8 is mirror-finished.

In the third step, as shown in FIG. 7C, a pair of core bar halves 5Aa,
At least one of the inner side surfaces 5b of 5Bb is coated with a nonmagnetic material such as silicon dioxide, glass or ceramic by physical vapor deposition to form a magnetic gap G.

In the fourth step, as shown in FIG. 8A, both core bar halves 5 with the magnetic gap G interposed therebetween.
Aa and 5Bb are brought into contact with each other and the notch grooves 8 facing each other are precisely combined with each other, and the combined notch groove 8 is filled with a filler 9 made of a nonmagnetic material such as glass, ceramic, or synthetic resin. At the same time, the core window halves 5Aa and 5Bb are joined to each other by filling the joint window 7 with the joint material 10 made of the same non-magnetic material to form ten kinds of core bars 5C. The front side b and the rear b on the 8th side are mirror-polished to inspect whether the notch grooves 8 are precisely united. If the result of the inspection is that they are not united precisely, they will be rejected as defective products. For the core bar 5C that is precisely combined, FIG.
As shown in FIG. 3, the magnetic tape sliding surface C is formed by subjecting the front surface i on the notch groove 8 side to a curved surface with a predetermined curvature radius R.

In the fifth step, as shown in FIG. 8C, the core bar 5C is sliced along a virtual line S1 crossing the center of each notch groove 8 at a predetermined azimuth angle θ with respect to each magnetic gap G. As a result, 16 types of magnetic head cores 5 are formed as shown in FIG.
JP-A-55-12525

In the above-described conventional configuration, both core bar halves 5Aa, 5 are formed at an early stage (second process) of the manufacturing process.
By forming a plurality of cutout grooves 8 on the edge of Bb [see FIG. 7B], the track t
Since the width is determined, many (10 types) core bar halves 5Aa and 5Bb are used in this process.
Must be formed (see A to J in FIG. 6). Therefore, in the subsequent steps, the various types of core bar halves 5Aa and 5Bb must be processed separately, which takes time and effort, lowers the processing efficiency, and increases costs. .

Further, in the fourth step, when the two core bar halves 5Aa and 5Bb are brought into contact with each other, when the notch grooves 8 facing each other are merged (see FIG. 8A), the notch grooves 8 are connected to each other. In this case, the track forming surfaces T facing each other with the magnetic gap G interposed therebetween are not precisely aligned, resulting in a defective product.

Further, after the core bar halves 5Aa and 5Bb are joined to form the core bar 5C, the core bar 5C is mirror-polished (see (a) and (b) in FIG. 8 (a)) so that the notch grooves 8 are precisely combined. It is necessary to inspect whether or not the mirror has been polished, and it takes time and effort to perform the mirror polishing and inspection.

As a technique for solving the above problems, there is a technique described in JP-A-7-129910. As shown in FIG. 9, a pair of core halves 5A and 5B made of a magnetic material whose inner side surface 5b is inclined at a predetermined azimuth angle θ are used, and the core halves 5A and 5B are opposed to each other. The magnetic head core 5 is formed by bonding the inner side surfaces 5b to each other with the nonmagnetic bonding material 10 with the magnetic gap G interposed therebetween. From the outer side surface 5a of one core half body 5A on both front edges of the magnetic head core 5. A pair of cutout grooves 12 that pass through the magnetic gap G and reach the outer surface 5a of the other core half 5B are formed over the entire length L of the magnetic head core 5, so that the track scanning direction X and Parallel track forming surfaces T (see phantom lines in FIG. 9) are left uncut, and the track forming surfaces T are curved to form magnetic tape sliding surfaces C.

According to the above configuration, a pair of notched grooves 12 are formed on both front edges of the magnetic head core 5 over the entire length L of the magnetic head core 5, so that the magnetic tape sliding in an extremely thin and long state is formed on the front surface of the magnetic head core 5. Since only the surface C is left uncut, the magnetic tape sliding surface C in an extremely thin and long state is easily worn or damaged by contact with the magnetic tape, and the recording and reproducing performance is degraded in a relatively short period of time. Cheap.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional drawbacks, the present invention provides a magnetic head capable of maintaining a high performance over a long period of time by precisely setting a track width, high processing efficiency, no defective product, and a manufacturing method thereof. It is aimed.

In order to achieve the above object, the invention according to claim 1 uses a pair of core halves made of a magnetic material whose inner surface is inclined at a predetermined azimuth angle, and the inner halves of the core halves facing each other are used. A magnetic head core for two heads is formed by bonding the side surfaces with a non-magnetic bonding material with a magnetic gap interposed therebetween, and passes through the magnetic gap from the outer side surface of one core half body on both side edges of the front surface of the magnetic head core. By forming a pair of notch grooves reaching the outer surface of the other core half over the entire length of the magnetic head core, a track forming surface parallel to the track scanning direction is left between the notch grooves, and the track forming surface A magnetic tape sliding surface is formed by subjecting the magnetic tape to a curved surface. By moving the magnetic tape relatively along the magnetic tape sliding surface, the magnetic tape is recorded. In a magnetic head adapted to perform reproduction, a pair of notches extending over the entire length of the magnetic head core is formed by subjecting the front surface of the magnetic head core to a curved surface instead of forming a pair of notched grooves over the entire length of the magnetic head core. A magnetic tape sliding surface is formed so as to remove the both ends of each notch groove while leaving the central portion of the groove, and the bottom surface of each notch groove is formed in an arc shape and filled in each notch groove It is characterized by not being filled with material.

In a second aspect of the invention, a pair of core halves made of a magnetic material whose inner side surfaces are inclined at a predetermined azimuth angle is used, and the inner side surfaces of the two core halves facing each other are sandwiched by a magnetic gap. The magnetic head core is formed by bonding with a nonmagnetic bonding material, and passes through the magnetic gap from the outer surface of one core half to the outer surface of the other core half on both side edges of the front surface of the magnetic head core. By forming a pair of cutout grooves over the entire length of the magnetic head core, a track forming surface parallel to the track scanning direction is left between the cutout grooves, and the front surface of the magnetic head core is subjected to curved surface processing, A magnetic tape sliding surface is formed so as to leave the center portion of each notch groove and to delete both end portions of each notch groove.

According to a third aspect of the present invention, in the second aspect of the present invention, the bottom surface of each notch groove is formed in an arc shape.

In the first aspect of the present invention, the plurality of magnetic plates are provided with a plurality of grooves for winding windows and a plurality of grooves for bonding windows at predetermined intervals in the plurality of magnetic plates, and in the second step, After the mirror plates are processed on the inner surfaces facing each other of the magnetic plates, the inner surfaces of the magnetic plates are brought into contact with each other with a magnetic gap interposed therebetween, and bonding processing with a nonmagnetic bonding material is performed on the concave grooves. The magnetic plates are joined together to form a magnetic laminate, and in the third step, the portion facing the bottom surface of each junction window groove in the magnetic laminate is perpendicular to the magnetic gap formation direction. A plurality of core plates are formed by slicing along the direction, and in the fourth step, each core plate is substantially parallel to the magnetic gap at predetermined intervals with the groove for winding window and the groove for bonding window interposed therebetween. And slicing to form a core bar, In five steps, a plurality of cutout grooves are formed in parallel along the track scanning direction on the front surface of the core bar by a disk-like blade having a cross-sectional arcuate blade portion, thereby forming a track forming surface between the cutout grooves. After forming a magnetic tape sliding surface so as to remove the both ends of each notch groove, leaving a center portion of each notch groove, by applying a curved surface processing to the front surface of the core bar, In a sixth step, the core bar is sliced so as to cut through the notch grooves, thereby forming a magnetic head core composed of a pair of core halves joined with a magnetic gap therebetween.

The invention according to claim 1 corresponds to one embodiment (see FIG. 1), and according to this, both ends of the sliding surface of the magnetic tape are deleted from both ends of each notch groove. Since the surface of the magnetic tape is subjected to the surface pressure by the both ends of the wide state, the central portion (track forming surface) of the ultrafine state sandwiched between both notched grooves of the magnetic tape sliding surface is formed. It can be prevented from being worn or damaged by contact with the magnetic tape. In addition, since the track forming surface that is relatively long and parallel to the track scanning direction is left between the notched grooves,
It is suitable for precisely setting the track width according to the demand for higher density. Furthermore, since the filler is not filled in the notch grooves, the filler does not impair the adhesion between the magnetic tape and the track forming surface as in the past, and the gap loss in recording and reproduction is reduced. Can do. In addition, by forming the bottom surface of each notch groove in an arc shape, the base of the track forming surface is thick, so with the impact when scraping both notch grooves with a blade,
By preventing the track forming surface from being damaged, defective products can be prevented from being generated. Furthermore, since the edge of each notch groove is formed in an arc shape, a pseudo gap does not occur at the edge of each notch groove. In short, it is possible to provide a two-head magnetic head core that maintains high recording and reproduction performance over a long period of time.

According to the second aspect of the present invention, both ends of the sliding surface of the magnetic tape are formed in a wide state by deleting both ends of each notch groove, and the both ends of the wide state are used to form the magnetic tape. Since it receives surface pressure, it can prevent the center portion (track forming surface) of the ultrafine state sandwiched between both notched grooves of the sliding surface of the magnetic tape from being worn or damaged by contact with the magnetic tape, High recording and playback performance can be maintained over a long period of time.

In addition, since the track forming surface that is relatively long and parallel to the track scanning direction is left between the cutout grooves, it is suitable for precisely setting the track width in response to a demand for higher density. Furthermore, since the filler is not filled in the notch grooves, the filler does not impair the adhesion between the magnetic tape and the track forming surface as in the past, and the gap loss in recording and reproduction is reduced. Can do.

According to invention of Claim 3, by forming the bottom face of each notch groove in circular arc shape,
Since the base of the track forming surface is thick, it is possible to prevent the track forming surface from being damaged by the impact when the notch grooves are scraped off with a blade, so that a defective product does not occur.
Moreover, since the edge of each notch groove is formed in an arc shape, a pseudo gap is not generated at the edge of each notch groove.

According to the invention described in claim 4, a plurality of notch grooves are formed in parallel along the track scanning direction on the front surface of the core bar at a late stage of the manufacturing process (fifth process). Since the type classification is delayed until the stage, compared to the conventional method of forming notched grooves at an early stage, compared to the case of classifying into multiple types, processing takes less time and time, and the processing efficiency is high.
Cost can be reduced.

In addition, since notched grooves are formed on both core bar halves joined across the magnetic gap, the tracks facing each other across the magnetic gap of both core bar halves are precisely aligned, It is possible to eliminate the occurrence of defective products due to the positional shift of the notch grooves as in the prior art.

Furthermore, since the mirror finish for confirming the track width is not necessary, the cost can be reduced by the amount that is unnecessary.

In addition, a magnetic head core is formed from a magnetic laminate through a large number of core bars, and the magnetic head can be mass-produced at a lower cost than when a magnetic head core is formed from a conventional core bar.

FIG. 1 shows a magnetic head core 5 for two heads of a magnetic head 1 according to an embodiment of the present invention [FIG.
(See (b)), and a pair of core halves 5A and 5B made of a magnetic material having both inner and outer side surfaces 5a and 5b inclined at a predetermined azimuth angle θ are used. , 5B are joined to each other by a non-magnetic joining material 10 with a magnetic gap G interposed therebetween, and a magnetic head core 5 is formed. The outer surface 5a of the other core half 5B through the magnetic gap G from the outer surface 5a of the other core
Are formed over the entire length L of the magnetic head core 5, a track forming surface T parallel to the track scanning direction X is left between the notched grooves 12, and is formed on the front surface of the magnetic head core 5. By applying curved surface processing, the magnetic tape sliding surface C is formed so as to leave the center of each notch groove 12 and delete both ends of each notch groove 12,
The bottom surface 12a of each notch groove 12 is formed in an arc shape, and the notch groove 12 is not filled with the filler 9 (see FIG. 5). Since the configuration other than the above is substantially the same as the configuration shown in FIGS. 4 to 9, the same reference numerals are given to the same portions and the description thereof is omitted.

According to the above configuration, both end portions C of the magnetic tape sliding surface C formed on the front surface of the magnetic head core 5.
a is formed in a wide h state by deleting both end portions of each notch groove 12, and the surface pressure of the magnetic tape is received by both end portions Ca in the wide h state. The extremely thin central portion Cb (track forming surface T) sandwiched between the two notched grooves 12 can be prevented from being worn or damaged by contact with the magnetic tape, and the recording and reproducing performance can be maintained high over a long period of time. can do.

In addition, since the track forming surface T that is relatively long and parallel to the track scanning direction X is left between the notched grooves 12, the track t width can be precisely set according to the demand for higher density. Are suitable. Further, since the filling material 9 (see FIG. 5) is not filled in the notch grooves 12, the filling material 9 does not impair the adhesion between the magnetic tape and the track forming surface T as in the prior art, and recording is performed. In addition, it is possible to reduce the gap loss in regeneration. Furthermore, since the base of the track forming surface T is thickened by forming the bottom surface 12a of each notch groove 12 in an arc shape [see FIG. 1 (d)], the notch grooves 12 are formed on the blade B [ FIG. 3 (a)
The track forming surface T is not damaged by the impact at the time of scraping in the reference, so that a defective product can be prevented from being generated. Moreover, since the edge 12b of each notch groove 12 is formed in an arc shape (see FIG. 1B), no pseudo gap is generated at the edge 12b of each notch groove 12. In short, it is possible to provide the magnetic head core 5 for two heads that maintains high recording and reproduction performance over a long period of time.

The manufacturing method of the magnetic head 1 will be described. In the first step, as shown in FIG. 2A, for example, a plurality of magnetic materials such as a laminate of high permeability ferrite, sendust alloy, or amorphous magnetic alloy band are used. The magnetic plate 5D is provided with a plurality of grooves 6a and 7a with a plurality of recesses 6a for the winding window 6 and a groove 7a for the joining window 7 in parallel with each other at a predetermined interval. To do.

In the second step, as shown in FIG. 2 (b), the mirror plate is applied to the mutually opposing inner surfaces of the magnetic plate 5D with a plurality of concave grooves 6a and 7a and the thin magnetic plate 5D shown at the right end in the figure. The inner surfaces of the magnetic plates 5D are brought into contact with each other with a magnetic gap G made of a non-magnetic material such as silicon dioxide, glass, or ceramic interposed therebetween, and the grooves 6a and 7a are made of glass, ceramic, The magnetic laminate 5E is formed by bonding the magnetic plates 5D to each other by bonding with a nonmagnetic bonding material 10 such as a synthetic resin.

In the third step, as shown in FIG. 2B, a virtual line S <b> 2 in a direction orthogonal to the direction in which the magnetic gap G is formed at a location facing the bottom surface of the groove 7 a for each joint window 7 of the magnetic laminate 5 </ b> E. And a plurality of core plates 5F are formed (see FIG. 2C).

In the fourth step, as shown in FIG. 2 (c), each core plate 5F has a groove 6a for the winding window 6 and a groove 7a for the bonding window 7 sandwiched therebetween, and the magnetic gap G is almost equal to the predetermined interval. Parallel virtual line S
The core bar 5C is formed by slicing along 3 (see FIG. 3A).

In the fifth step, as shown in FIG. 3 (a), a plurality of cutout grooves 1 are formed on the front surface of the core bar 5C composed of the core bar halves 5Aa and 5Bb by the disk-like blade B having the cross-sectional arcuate blade portion Ba.
3 is formed in parallel along the track scanning direction X, and the track forming surface T is left uncut between the cutout grooves 12, and then the front surface of the core bar 5C is subjected to curved surface processing to obtain FIG. As shown in b), the magnetic tape sliding surface C is formed so as to leave the center portion of each notch groove 12 and delete both end portions of each notch groove 12.

In the sixth step, as shown in FIG. 3B, by slicing the core bar 5C so as to vertically cut each notch groove 12 along the virtual line S4, as shown in FIG. G
A magnetic head core 5 composed of a pair of core halves 5A and 5B joined together is formed.

According to the above configuration, the core bar 5 is formed at a late stage (fifth process) of the manufacturing process shown in FIG.
A plurality of notched grooves 12 are formed in parallel on the front surface of C along the track scanning direction X. Since the classification is delayed until this stage, the notched grooves 12 are formed at an early stage of the prior art. Compared with the case of classifying into many types, the processing does not take time and effort, the processing efficiency is high, and the cost can be reduced.

In addition, since the cutout grooves 12 are formed in the core bar halves 5Aa and 5Bb joined with the magnetic gap G interposed therebetween, they face each other with the magnetic gap G between the core bar halves 5Aa and 5Bb interposed therebetween. Thus, the track t to be precisely aligned is eliminated, and the occurrence of defective products due to the positional shift of the notch grooves 12 as in the conventional case can be eliminated.

Furthermore, since the mirror finish for confirming the track t width is not required, the cost can be reduced by the amount that is unnecessary.

In addition, the magnetic head core 5 is formed from the magnetic laminated body 5E through a large number of core bars 5C, and the magnetic head 1 is mass-produced at a lower cost than when the magnetic head core 5 is formed from the conventional core bar 5C. be able to.

In the above embodiment, the recording / reproducing magnetic head 1c provided in the two-head type (2HD) cylinder head 2 shown in FIG. 4B has been described as an example. However, the present invention is not limited to this. 4 head Hi-Fi type (4HD) cylinder head 2 shown in FIG.
The present invention can also be applied to the recording / reproducing magnetic head 1a and the Hi-Fi magnetic head 1b.

(A) is a perspective view showing a magnetic head core of a magnetic head according to an embodiment of the present invention, (b) is a plan view thereof, (c) is a front view thereof, and (d) is a side view thereof. (A)-(c) is a perspective view which shows the first half of the manufacturing process of a magnetic head core. (A)-(c) is a perspective view which shows the second half of the manufacturing process of a magnetic head core. (A) And (b) is a schematic plan view which shows a cylinder head. (A) is a perspective view which shows a prior art example, (b) is the top view, (c) is the front view, (d) is a side view. It is explanatory drawing which shows the classification classification table of a magnetic head. (A)-(c) is a perspective view which shows the first half of the manufacturing process of a magnetic head core. (A)-(d) is a perspective view which shows the second half of the manufacturing process of a magnetic head core. It is a perspective view which shows the other example of the past.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Magnetic head 5 Magnetic head core 5A, 5B Core half body 5Aa, 5Bb Core bar half body 5C Core bar 5D Magnetic plate 5E Magnetic laminated body 5F Core plate 5a Outer side surface of core half body 5b Inner side surface of core half body 6 Winding window 6a Winding Groove for wire window 7 Joint window 7a Groove for joint window 9 Filler 10 Joint material 12 Notch groove θ Azimuth angle G Magnetic gap T Track forming surface C Magnetic tape sliding surface Ca Both ends of magnetic tape sliding surface Cb Central part of magnetic tape sliding surface t Track X Track scanning direction B Blade

Claims (4)

A pair of core halves made of a magnetic material whose inner side surfaces are inclined at a predetermined azimuth angle are used, and the mutually facing inner side surfaces of both core halves are joined with a nonmagnetic bonding material with a magnetic gap interposed therebetween. A magnetic head core for two heads is formed, and a pair of notch grooves that pass through the magnetic gap from the outer surface of one core half and reach the outer surface of the other core half are formed on both side edges of the front surface of the magnetic head core. By forming it over the entire length of the magnetic head core, a track forming surface parallel to the track scanning direction is left uncut between the notched grooves, and a curved surface processing is applied to the track forming surface to form a magnetic tape sliding surface. In a magnetic head adapted to perform recording and reproduction with respect to the magnetic tape by relatively running the magnetic tape along the magnetic tape sliding surface, Instead of forming the notch grooves over the entire length of the magnetic head core, by subjecting the front surface of the magnetic head core to a curved surface, the center of the pair of notch grooves extending over the entire length of the magnetic head core is left, and both ends of each notch groove The magnetic tape sliding surface is formed so as to delete the part, and the bottom surface of each notch groove is formed in an arc shape,
A magnetic head characterized in that a filling material is not filled in each notch groove. A pair of core halves made of a magnetic material whose inner side surfaces are inclined at a predetermined azimuth angle are used, and the mutually facing inner side surfaces of both core halves are joined with a nonmagnetic bonding material with a magnetic gap interposed therebetween. A magnetic head core is formed, and a pair of notch grooves passing through the magnetic gap from the outer surface of one core half to the outer surface of the other core half are formed on both side edges of the front surface of the magnetic head core. By forming over the entire length, a track forming surface parallel to the track scanning direction is left uncut between the notch grooves, and the front surface of the magnetic head core is curved to leave the center of each notch groove. A magnetic head having a magnetic tape sliding surface formed so as to delete both end portions of each notch groove. 3. The magnetic head according to claim 2, wherein the bottom surface of each notch groove is formed in an arc shape. In the first step, a plurality of grooves for winding window and a groove for bonding window are recessed in parallel to each other at a predetermined interval on a plurality of magnetic plates, and in the second step, the inner surfaces of the magnetic plates facing each other are arranged. After mirror processing on the side surfaces, the inner surfaces of the magnetic plates are brought into contact with each other with a magnetic gap in between, and the magnetic grooves are bonded by bonding the non-magnetic bonding material to the concave grooves. In the third step, a portion facing the bottom surface of each groove for connecting windows of the magnetic laminate is sliced along a direction perpendicular to the magnetic gap formation direction in the third step, and a plurality of the magnetic laminates are formed. A core plate is formed, and in the fourth step, core bars are formed by slicing each core plate approximately parallel to the magnetic gap at predetermined intervals with the groove for winding window and the groove for bonding window interposed therebetween. In the fifth step, the cross-sectional arc shape By forming in parallel along a plurality of channel cutout in the track scan direction in front of the core bar by a disc-shaped blade having a part,
After leaving the track formation surface between the notch grooves, the front surface of the core bar is subjected to a curved surface process so that both ends of the notch grooves are deleted while leaving the center of the notch grooves. In the sixth step, a magnetic head core composed of a pair of core halves joined together with a magnetic gap interposed therebetween is formed by slicing the core bar so as to longitudinally cut each notch groove. A method of manufacturing a magnetic head.