JPS6148111A - Manufacture of magnetic head - Google Patents

Abstract

PURPOSE:To attain the manufacture of a magnetic head with high track density by applying chamferring and grinding to the shoulder of a slot with a grinder made by combining minute grinding grains softly after the slot is formed by grinding at first in the slotting process of a head core so as to prevent reduction in output and increase in the error rate due to inadequate gap shape. CONSTITUTION:At first, a magnetic material 22 where a slot forming schedule face is ground and polished is prepared as shown in figure (a), and a prescribed number of slots are formed by a shaping grinder 23 as shown in figure (b). The grain particle diameter of the grinder 23 used in this case can be of medium particle. After the magnetic material 22' is shaped roughly for the slots, chamferring finish is attained as shown in figure (c). The grinder 24 is formed by using minute grain particles and softer binder more than those of the grinder 23, and when the tip angle theta is too small, the advantage of this invention is less and when too large, cracks or chipping are caused to the shoulder 25 of the slot, then it is required to set a proper tip angle theta.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a method for manufacturing a magnetic head used in a recording/reproducing device for a floppy disk for high-density recording. [Prior Art] Like a magnetic disk, a disc-shaped When recording tracks are formed along the circumferential direction of a recording medium, if the distance between tracks M is narrowed in order to increase the recording density, cross-stiffness from adjacent tracks increases during reproduction, which is undesirable. Furthermore, there is also the problem that off-track caused by positioning errors in the head positioning mechanism deteriorates the S/N ratio and increases the error rate. ° For this reason, conventional magnetic heads have one recording/reproducing gap and two As a result, as shown in FIG. 1, there is a signal area 4 on the recording medium due to the recording/reproducing gap 1, and a no-signal area due to the erasing gaps 2 and 3. 5 and 6 are formed.

In this way, the above-mentioned problem is solved by providing guard bands on both sides of the recording track.

In the past, great efforts have been made to improve the recording surface density, but recently a magnetic head with the structure shown in Figure 2 (for example, Japanese Patent Application Laid-Open No. 57-44219) has appeared, which has improved the trunk density in particular. As shown in the figure, the structure of this magnetic head, which has been significantly improved in terms of performance, uses a closed magnetic path with a recording/reproducing gap.
The part (15, 15,
16 and 17 are provided with a filling portion made of glass or the like as described above, and a non-magnetic material such as glass is also filled between these two parts 7 and 8. And each has a winding groove 1
9.20 is formed.

Moreover, the shape of the recording medium contact surface of the magnetic head in FIG. 2 is shown in FIG. 3. ◇The width of the recording/reproducing gap is groove part 1! l'
, 14'. The width 2□ of the erasing gap is defined by the grooves 15', 16', and 17'.The width of the signal recorded by this magnetic head separates the erasing gap into two, rather than the recording/reproducing gap width 21. #J2 of groove portion 16'. is small, so it ends up being 23.0The structural advantage of this magnetic head is that
By defining the recording signal width on the medium as described above, the guard punts 5 and 6 shown in FIG. To proceed, the respective gap widths λ1, 2 . and recording signal width 2. This poses a problem in the manufacturing method of the magnetic head, and is particularly difficult in processing the magnetic material forming the erasing gap.

By the way, Figure 4 is a diagram of a part of the head fabric block for forming the vanishing gears for cutting each head into rounds after being filled with non-magnetic material. This block has many grooves cut into it. The quality of the method for manufacturing the grooves is a factor in the manufacture of magnetic heads that enable higher density. These grooves are usually formed by profile-grinding a flat plate of magnetic material. However, since polycrystalline materials are often used for these magnetic materials due to raw material costs, chips and cracks are likely to occur in the shoulder portions 21 when forming the grooves. A magnetic head that cannot have a perfect shape as shown in FIG. 3 suffers from a decrease in magnetic conversion efficiency because 2 in FIG. 6 cannot be ensured, or 2. because 2 cannot be ensured. is 2
□As a result, it has the disadvantage that a sufficient guard band cannot be created and the error rate due to noise increases. Therefore, in the magnetic head having the structure according to the present invention, in order to ensure the formation of the groove shape, countermeasures are taken such as making the abrasive grains of the groove forming magnet finer and softening the bonding agent of the grinding wheel. He was giving lectures.

However, both of these measures shorten the life of the grinding wheel.
This cannot be done blindly.Also, as the size of the groove 22 becomes smaller in the future, the strength of the crest defined by the groove will decrease, and the ridge will break when the groove is formed.

〔the purpose〕

The present invention is intended to solve these problems, and its purpose is to provide a method for manufacturing a magnetic head that is compatible with higher density.

〔overview〕

The manufacturing method of the magnetic head of the present invention includes, in the grooving process of the head core, first forming the groove shape by grinding, and then chamfering and grinding the shoulders of the groove using a grindstone in which finer abrasive grains are bonded more softly. It is characterized by forming grooves by.

〔Example〕

Hereinafter, the present invention will be described in detail based on examples.

FIG. 5 shows the manufacturing method of the present invention. First, as shown in (α), a magnetic material 22 whose surface on which the groove is to be formed is ground and polished is prepared. Then, as shown in (6), the required number of magnetic materials 22 is prepared. Grooves are formed using the general grindstone 25. The grindstone 23 used at this time may be a grindstone with a medium abrasive grain size, and the groove shape may be different from that shown in the figure. As described above, the magnetic material 22' having the rough shape of the groove is chamfered as shown in (c). The whetstone 24 has finer abrasive grains than the whetstone 25 and uses a softer binding material.

If the tip angle θ of the grindstone 24 is too small, the advantages of the present invention will be diminished, and if it is too large, chips or cracks will occur in the shoulder portion 25 of the groove.For this reason, it is important to set an appropriate tip angle θ. be.

In subsequent processing, the grooved hexed fabric blocks are filled and fused with a non-magnetic material to manufacture a magnetic head (for example, Japanese Patent Laid-Open No. 57-44219).

〔effect〕

As described above, according to the present invention, the shape of the gap portion can be stably formed despite the minute recording width, and the decrease in output and increase in error rate due to defects in the narrow gear shape can be prevented. This has the effect of making it possible to manufacture a magnetic head with high track density.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing recording tracks formed by a magnetic head. FIG. 2 is an external perspective view of an example of a conventional magnetic head. FIG. 3 is a plan view of the recording medium contact surface of this magnetic head. FIG. 4 is a perspective view of a head core block in which a groove has been formed to form an erasing gap of this magnetic head. FIGS. 5(α) to (c) are diagrams showing the groove forming process of the present invention.・Recording track 5.6... Guard band 7... Recording/reproducing head element section 8...
Erasing head element section 9.10...Magnetic material for forming a recording/reproducing gap 11.12...Magnetic material for forming an erasing gap 13.14...Width of the recording/reproducing gap Regulate 1
Non-magnetic material 15 filled in the grooves for 3' and i4'
．． 16, 17...15' regulating the width of the erasing gap
, 16'17' Non-magnetic material 18 filled in the groove for recording and reproducing head elements and erasing head elements. Hole 21 for winding...
...Shoulder portion 22 22' between the vanishing gap forming surface and the groove
, 22'...Magnetic material 23 before groove formation constituting the head element section...Grindstone 24 for groove formation...Grindstone 25 for finishing the shoulder of the groove...
・Above the shoulder of the groove

Claims (1)

[Claims] In a magnetic head that has both a recording/reproducing gap and an erasing gap whose width is defined by a groove filled with a non-magnetic material, in order to form the groove, first, the shape of the bottom of the groove is created by profile grinding. A method of manufacturing a magnetic head, the method comprising: adjusting the shape of the groove by chamfering the shoulders of the groove using a finishing grindstone.