JPH03201207A - Production of composite type floating magnetic head - Google Patents

Abstract

PURPOSE:To improve the yield of a magnetic core and to reduce the cost of this head by subjecting only one of any of the cut surfaces cut on the magnetic core to lapping finishing and subjecting the core to prescribed track working with the finished surfaces as a reference for working, thereby forming a track. CONSTITUTION:The one cut surface 9 of either of the cut surfaces 9, 10 of the magnetic core 4 is formed by lapping to the lapped surface 9' so as to form the reference plane for track working. The surface side 11 facing oppositely the lapped surface 9' is thereafter subjected to removal working on the basis of the lapped surface 9' to form the track TW of a prescribed width size. The generation of cracking and chipping at the time of the track working is, therefore, suppressed and the dimensional accuracy of the tack width is improved. The yield at the time of the track working is improved in this way and the cost of the core is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention applies to magnetic recording media such as magnetic disks.
The present invention relates to a method of manufacturing a composite floating magnetic head that performs recording and reproduction.

"Prior Art" As shown in FIG. 5, a composite floating magnetic head 101 is
A magnetic core 104 is inserted into a core slot groove 103 of a slider 102 made of a non-magnetic material and fixed with a glass 105.

The magnetic core 104 has a C-bar 106 and an I-bar 107 bonded to each other by glass with a working gap 10B interposed therebetween.

One way to achieve high-density recording in the composite floating magnetic head 101 is to improve the linear recording density, and as an important element, the linear recording density can be improved by narrow tracks in the magnetic core 104. . The width of this track is the same as the width of the signal recorded on the magnetic recording medium.

By the way, the core for a conventional composite floating magnetic head has a sixth core.
As shown in the figure, after the C bar 106 and the ■ bar 107 are reinforced with a retaining glass 103 and bonded together, they are cut into magnetic cores 104 with a predetermined thickness. Next, as shown in FIG. 7, both sides 109 of the magnetic core 104 in FIG. 7a are attached.
0 is polished, and both side surfaces are polished to give polished surfaces 109' and 1)0', as shown in FIG. 7b. Next, the 7th C
As shown in the figure, based on the polished surface 109' of either of the polished surfaces 109' and 1)0'',
Step part 1) By removing 1, a predetermined track width TW is obtained.
It had been processed.

In another example, as shown in FIG. 8a, the magnetic core 10
Both sides 109 of 4 1) without wrapping 0, as shown in Figure 8b, the cut surface 109 1)
0, both sides of the approximately central part of the thickness of the magnetic core 104 1) 2
- By removing 1) 3, the predetermined track width TW was processed. This example is described in detail in, for example, Japanese Patent Publication No. 15929/1983.

“Problem to be Solved by the Invention” In the conventional example shown in FIG. 7 as described above, the magnetic core 10
Both sides of 4 109 ・1) Since 0 was finished in the lapping process, the lapping process was two processes on both sides, requiring a large number of man-hours.

On the other hand, in the conventional example shown in FIG. 8, although the lapping process is no longer necessary, two lapping processes are required for track processing, and even in this case, the number of man-hours cannot be reduced.

Furthermore, in this case, when the track width TW is narrower than 15 μm, there is a problem that the yield is reduced due to chipping of the trunk portion and frequent occurrence of cranks.

The present invention has been made to solve the above-mentioned problems, and provides a method for manufacturing an inexpensive composite flying magnetic head by reducing the number of processing steps and improving the yield of magnetic cores. .

"Means for Solving the Problems" In view of the above circumstances, the present invention aims to reduce the number of processing steps, improve the yield of magnetic cores, and provide an inexpensive composite magnetic head core. After that, a lapping finish is applied to only one of the cut surfaces of each magnetic core, the other surfaces are left as they were at the time of cutting, and a predetermined track processing is performed using the lapping finished surface as a processing reference. It is designed to form a .

"Function" Even if the number of lapping surfaces is reduced by one compared to the conventional example, highly accurate track processing is possible because a predetermined reference surface exists.

"Embodiments" The present invention will be described in detail below based on embodiments of the accompanying drawings.

C bar 6 and 1 bar 7 are made in exactly the same way as in the conventional example shown in FIG.
After gap-joining them through a gap glass 3, the magnetic core 4 is cut into a magnetic core 4 of a predetermined thickness by a generally well-known method such as wire cutting.

As shown in FIG. 1, only one of the cut surfaces 9 and 10 of the magnetic core 4 is formed into a lapped surface 9' by lapping so as to serve as a reference surface for track processing. At this time, the surface roughness of the lapping finished surface 9' needs to be at least about 0.1 μmRa. Thereafter, the trunk TW having a predetermined width is formed by removing the surface side 1) facing the lapping surface 9'' using the lapping surface 9'' as a reference.

Note that it is necessary to machine the track width TW accurately and in parallel over the entire range of the track processing depth H.
In this case, if the track processing depth H exceeds 150 μm, chipping or cracking of the track portion due to track processing is likely to occur, resulting in a very poor processing yield. On the other hand, when the track processing depth H is reduced, the electromagnetic conversion characteristics of the magnetic head are adversely affected.

In order to solve this problem, the track machining depth H is set to be equal to the step width W'' of the track machining, as shown in FIGS. 2 and 3.

When the track machining depth H is made equal to the step width W' and the distance between the tracks, the reaction force Fy of the step portion against the diamond grinding wheel 21 during track machining is the same as the reaction force Fx in the side direction of the track, as shown in Fig. 4. Therefore, track machining can be performed without applying excessive force to the step portion or the track portion. Therefore, the occurrence of cranks and chips during track machining is minimized, and the dimensional accuracy of the track width is also improved. The core thickness is 178 μm, the track width is 16 μm, and when the conventional track depth H = 150 μm, the processing yield was about 80%, but when the track depth H = 75 μm, the processing yield was over 95%. It became.

Note that the smaller the track processing depth H is, the more reliable the processing yield will be, but if it is too small, the electromagnetic conversion characteristics of the magnetic core will deteriorate, which is not preferable. In terms of electromagnetic conversion characteristics, the magnetic core thickness is 178μ
m, track machining depth H in case of track width 16 μm
The optimum value was 50 μm to 100 μm.

"Effects of the Invention" As described above, the present invention applies a lapping finish to only one of the cut surfaces of each magnetic core after gap bonding, and leaves the other surfaces in the same state as when they were cut. Then, using the lapping finished surface as a processing reference, a predetermined trunk processing is performed to form a track, so the lapping processing process is reduced to 1 compared to the conventional example shown in Fig. 7.
Although the number of lapping processes is not reduced compared to the conventional example shown in Fig. 8, the yield during track machining can be improved, and compared to the conventional example, the track machining accuracy is the same, but the lapping process is not reduced. Cores for floating magnetic heads can be manufactured at low cost and with high yield.

[Brief explanation of drawings]

FIG. 1 is a front view of a specific embodiment of the present invention, illustrating the manufacturing process thereof, FIG. 2 is a front view of a narrow track magnetic core, FIG. 3 is a side view of FIG. 2, and FIG. The figure is a side view showing the track processing state of the magnetic core shown in Figs. 2 and 3, Fig. 5 is a perspective view of a composite floating magnetic head, Fig. 6 is a perspective view illustrating the manufacturing process of the magnetic core, and Fig. 7 is a perspective view illustrating the magnetic core manufacturing process. The figure is a front view illustrating a conventional manufacturing process for a magnetic core, and FIG. 8 is a front view illustrating another conventional manufacturing process for a magnetic core. 4...Magnetic core TW...Tracking 9°・
・・Wrapping finish surface

Claims (1)

[Claims] (1) A method for manufacturing a composite floating magnetic head in which a magnetic core having a core track for recording and reproducing formed with a width narrower than the thickness of the core is inserted and fixed into a core slot groove of a slider made of a non-magnetic material. A method for manufacturing a composite flying magnetic head, characterized in that only one side of the head is formed into a lapped surface by lapping, and the lapped surface is used as a processing reference surface to form a track of a desired width.