JPH0592365A - Method of correcting ultra abrasive grain grinding wheel - Google Patents

Abstract

PURPOSE:To provide a magnetic disc unit having a high recording density by decreasing the width of a floating surface so as to reduce the degree of float-up. CONSTITUTION:There is provided a thin plate-like general grinding stone 3 which is applied over a base 4 formed therein with several grooves having a width greater than the thickness of an ultra abrasive grain grinding wheel 2 and a depth larger than the cutting degree of the grinding wheel. The edge of the ultra abrasive grain grinding wheel 2 is inserted into one of the grooves of the base 4 through the general grindstone 3 so as to correct the grinding wheel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head in a magnetic disk device and a method of manufacturing the same, and more particularly to a thin blade grindstone made of superabrasive grains for narrowing the rail width of the air bearing surface of the magnetic head with high precision. The present invention relates to a modification method suitable for molding.

[0002]

2. Description of the Related Art Conventionally, the correction of a superabrasive thin-blade grindstone used for processing hard and brittle materials such as magnetic heads has been described in p. 147, Proc. A square bar-shaped general grindstone called or a thin plate-shaped general grindstone called a dressing board is fixed on the table of the processing machine, and a high-speed rotating superabrasive grain thin blade grindstone is used as the general grindstone in an arbitrary amount within the range of the general grindstone. The tip of the grindstone is corrected by cutting only, and the superabrasive thin blade grindstone corrected as described above was used as it is for the forming processing of the rail of the magnetic head.

[0003]

In the above prior art, no consideration is given to the deterioration of the shape of the superabrasive grindstone due to the modification, and the tip of the superabrasive grindstone is tapered after the modification. The product processed by the grindstone has a problem that the squareness of the side surface of the groove or the cut surface is bad.

Particularly in the processing of the rail of the magnetic head of the magnetic disk device, the width of the air bearing surface must be narrowed with high precision in order to reduce the flying height of the head and to reduce the fluctuation of the flying height. Since the dimension of the thin film element cannot be reduced, it is necessary to make the shoulder portion of the air bearing surface into a fine stepped shape. At this time, if the precision of the grindstone is poor, it is difficult to secure the precision of the rail, and there is a problem that the element is damaged and the flying height varies greatly.

An object of the present invention is to provide a grindstone repairing method capable of simply and accurately repairing a thin-blade superabrasive grindstone, and by processing a magnetic head with high accuracy, a high recording density can be obtained. To provide a magnetic disk device of the above.

[0006]

In order to achieve the above object, according to the present invention, a thin board of a general grinding stone for dressing is attached on a comb-shaped base, and the groove of the base is penetrated through the dressing board. Fix while protruding the tip of the superabrasive grindstone inside.

[0007]

The function of the above technical means is as follows.

When a superabrasive grindstone is cut into a dressing board and the dressing board is thinned and processed with the grindstone penetrating, the inside and outside of the contact arc between the side surface of the superabrasive grindstone and the dressing board. The difference between
The dressing distance is made uniform, and the amount of dressing on the side surface becomes substantially equal on the inner and outer circumferences, so the taper on the side surface of the grindstone becomes smaller.

The product processed with such a grindstone has a good squareness, and in the case of a magnetic head, the variation in rail width is small and high-precision processing is possible. Therefore, a head with a narrower rail width and a stable flying height can be obtained. You can

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is a schematic configuration diagram of a method of correcting a superabrasive grindstone according to an embodiment of the present invention. 2 is a sectional view taken along the line II-II in FIG.

In FIG. 1, 1 is a grindstone spindle of a grinder (not shown), 2 is a superabrasive grindstone attached to the grindstone spindle 1, and this superabrasive grindstone 2 is a metal base 2b. And an abrasive grain layer 2a integrally formed on the outer peripheral surface of the base metal 2b by incorporating abrasive grains 2c made of a hard material such as diamond into a resin such as phenol, a metal such as copper, or an inorganic substance. , Rotate in the direction of the arrow.

Reference numeral 3 is a general grindstone made of plate-shaped WA grinds or GC grinds for correcting the superabrasive grindstone 2.
It is attached by a wax 6 to a comb-shaped base 4 having a plurality of grooves 5 arranged at equal pitches. As shown in FIG. 2, the size of the groove 5 is wider than the thickness of the grindstone of the superabrasive grindstone 2 and deeper than the depth of cut of the superabrasive grindstone 2, even if the superabrasive grindstone 2 rotates. The side surface and the end surface of the superabrasive grindstone 2 are prevented from coming into contact with the inner wall of the groove 5.
The operation of correcting the superabrasive grindstone 2 with high precision by the grindstone correcting method thus configured will be described.

When the superabrasive grindstone 2 is rotated and the grinding fluid 8 is supplied while the superabrasive grindstone 2 is cut deeper than the thickness of the plate-shaped general grindstone 3, the abrasive layer 2a of the superabrasive grindstone 2 is formed. Since the inner circumference side and the outer circumference side have different distances in contact with the general grindstone 3, the abrasive grain layer 2a is more likely to fall off in the longer contact part, and the cross-sectional shape of the superabrasive grain grindstone 2 is tapered. It will be in a state.

FIG. 3 is a side view of a superabrasive grindstone 2 and a general grindstone 3.
FIG. 6 is a relationship diagram of the difference between the inner and outer circumferences of the contact arc with the thickness of the general grindstone 3 and the cut amount of the superabrasive grindstone 2. When a general grindstone is penetrated, there is a point that the difference between the inner and outer circumferences becomes 0, but it is difficult to set the position, and the variation amount is large. Therefore, by using an extremely thin general grindstone 3 and reducing the thickness of the general grindstone 3 with respect to the depth of cut, it is possible to reduce the difference between the inner and outer peripheries of the contact arcs and make the abrasive grains fall out uniformly.

Similarly, even if the super-abrasive grindstone 2 is an all-blade type grindstone in which all of the grindstone layers 2a are used, the thinner the general grindstone 3 is, the smaller the difference between the inner and outer circumferences of the contact arc becomes.

By processing the magnetic head 9 with the superabrasive grindstone modified as described above, the rail width of the air bearing surface 10 can be accurately processed into a narrow stepped shape without damaging the element 13.

FIG. 4 is a sectional view when the magnetic head 9 is processed using a superabrasive grindstone modified by a conventional modification method.
The whetstone has a taper shape, and when you cut a specified amount,
The rail width of the air bearing surface 10 varies by the taper amount. FIG. 5 is a sectional view when a magnetic head is machined with a superabrasive grindstone modified by the grindstone modifying method according to the present invention using a general grindstone having a thickness of 0.1 mm. Grinding stone taper is 1 μm
Therefore, the taper of the rail side surface of the processed magnetic head is also small, and the variation in rail width is small.
As a result, the flying height can be obtained from 0.1 μm to 0.2 μm, and it is possible to obtain a high-performance magnetic disk device with a small variation in the flying height.

FIG. 6 is a perspective view of another embodiment of the present invention.
This is a case where a hard brittle material is subjected to groove processing or step processing and the grindstone is corrected in-process. The general grindstone 3 is fixed to the end surface of the product 11 on the table 13 of the grinder (not shown) via the spacer 12 so that the lower part of the general grindstone 3 becomes a void. After the product 11 is processed with the superabrasive grain grinding stone 2, the superabrasive grain grinding stone 2 is continuously passed through.
The shape can be corrected without deteriorating the shape, and accurate machining can always be performed.

[0020]

According to the present invention, since the rail portion of the magnetic head can be processed with high accuracy, the flying height can be reduced to 0.
It is possible to obtain a magnetic head of 1 μm to 0.2 μm,
Correspondingly, a high-performance magnetic disk device having a recording density of 70 Mbit / inch ² or more can be obtained.

Since the grindstone has a right angle cross section,
Less loss of the abrasive grain layer on the side of the grindstone when processing the magnetic head,
The life of the grindstone can be extended and it can be applied to high precision machining of other hard and brittle materials.

[Brief description of drawings]

FIG. 1 is a perspective view of a first embodiment of the present invention,

2 is a sectional view taken along line II-II of FIG.

FIG. 3 is an explanatory view of the relationship between the thickness of a general grindstone and the cutting amount of the grindstone, and the difference between the inner and outer circumferences of the contact arc between the side surface of the grindstone and the general grindstone;

[Figure 4]

FIG. 5 is a cross-sectional view of a magnetic head when processing a rail portion.

FIG. 6 is a perspective view of a second embodiment of the present invention.

[Explanation of symbols]

 1 ... Grindstone main spindle, 2 ... Super abrasive grain grindstone, 3 ... General grindstone, 4 ... Base

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Takeshita 2880 Kozu, Odawara City, Kanagawa Prefecture Hitachi Ltd. Odawara Factory

Claims (4)

[Claims] 1. A dressing on a thin plate in a super-abrasive thin-edged grindstone made of hard abrasive grains such as diamond, which is rotated at high speed around a spindle of a grindstone to cut hard or brittle material, or to perform groove processing or step processing. A method of repairing a superabrasive grindstone, characterized by forming a space under a superabrasive grain grindstone passing portion of a general grindstone for use in a state where the superabrasive grindstone is penetrated. 2. A rail processing method for an air bearing surface of a magnetic head according to claim 1, wherein a superabrasive grindstone formed by the correction method is used. 3. The magnetic head according to claim 1, wherein the shoulder of the air bearing surface is processed into a stepped shape by using the formed superabrasive grindstone, and the width of the rail is narrowed to reduce the area of the air bearing surface. .. 4. The magnetic head machined by the molded superabrasive grindstone according to claim 1, wherein a flying height is set to 0.
A magnetic disk device with a recording density of 70 Mb / inch ² or more, which is 2 μm or less.