JPH0388171A - Magnetic head - Google Patents

Abstract

PURPOSE:To improve sliding durability by providing either a spherical plane or a rotary elliptical plane at a magnetic core plane, and either a recessed plane part or a groove to which the chamfering working of an edge is applied on the plane of a slider on the other side. CONSTITUTION:The part of the spherical plane of the slider 11 is formed with the magnetic core plane 11B, the columnar part of the slider 11, and a magnetic core 11A. The inside of the core 11A is formed in a cavity room, and a coil 15 is provided in it. Meanwhile, the recessed plane part 13B ground in spherical shape is provided at a flat plane part 13A. Furthermore, another terminal which forms the opening state of the slider 13 is mounted on the plane on one side of a gimbal 14 so that the recessed plane part 13B of the slider 13 can be confronted with the core plane 11B of the slider 11. A state where a medium 100 is sandwiched between the sliders 11 and 13 can be generated. In such a way, head touch can be improved, and also, recording density characteristic can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic head used in a double-sided flexible magnetic disk device.

[Conventional technology]

In recent years, flexible magnetic disk drives (floppy disk drives) have been used in a wide range of applications, including external storage devices for small computers, as the media can be replaced and they are inexpensive. High reliability is achieved. Such floppy disk devices include a single-sided type that uses only one side of a flexible magnetic disk (floppy disk), and a double-sided type that uses both sides of the flexible magnetic disk (floppy disk).

For example, a magnetic head as shown in FIG. 5 is used in a single-sided floppy disk device.

This magnetic head consists of a spherical magnetic rad slider 52 attached to a carriage 51, and a fur felt (animal felt pad) 53 facing the spherical magnetic rad slider 52. A recording medium 100 is sandwiched between a spherical magnetic Rad slider 52 and a far felt 53.

Further, a double-sided floppy disk device uses a magnetic head as shown in FIG. 6, for example. This magnetic head is attached to a gimbal spring 61,
A slider 62 having a magnetic core 62A;
A slider 63 facing the magnetic core 63A and having a magnetic core 63A.
It consists of Further, an example of this slider 62, 63 is shown in FIG.

This slider 71 having a magnetic core 71B is of a flat double-barrel type. In a magnetic head having such a slider, as shown in FIG.
Recording or reproduction of information is performed by the magnetic core built into 3.

In order to achieve higher recording density in such floppy disk devices, unlike the conventional longitudinal recording method in which recording is performed by magnetizing the magnetic material of the recording medium in the in-plane direction, the thickness of the magnetic recording medium is A so-called perpendicular recording method has been developed in which recording is performed by magnetizing a magnetic material in a direction. Thin-film flexible magnetic disks made of CoCr alloy or the like, which have high recording density characteristics, are attracting attention as perpendicular recording media.

[Problem to be solved by the invention]

The above-mentioned magnetic head, for example, the spherical magnetic head shown in FIG.
In addition, since the medium is sandwiched between soft pads, the impact on the medium can be reduced, which is particularly advantageous in improving password durability for floppy disks using metal or oxide thin films. However, since only one side of the medium is used, it is disadvantageous in terms of recording capacity, and depending on the pad used in the magnetic head, there is a problem that it deforms over time due to the head load.

Further, a double-sided magnetic head as shown in FIG. 6 is advantageous in recording capacity because it can record on both sides of a floppy disk, and is currently the mainstream. However, since double-sided heads slide the floppy disk between hard sliders, the passware durability requirements for thin-film floppy disks that do not use a binder material, unlike traditional coating media, have become stricter. Generally, it is more difficult to reduce the head separation spacing than with spherical magnetic heads.

An object of the present invention is to eliminate the drawbacks of the magnetic head of the conventional double-sided floppy disk device as described above, and to provide a highly reliable device that has excellent high-density characteristics and prevents damage to the medium and magnetic head. The object of the present invention is to provide a magnetic head with improved characteristics.

[Means to solve the problem]

The present invention provides a magnetic head for a magnetic disk drive in which two sliders, at least one of which has a magnetic core, are disposed facing each other, wherein the magnetic core surface of the slider having the magnetic core has a substantially spherical and spheroidal shape. The present invention is characterized in that one of the body surfaces is provided, and the other slider surface is provided with either a concave portion or a groove with a chamfered edge.

[Effect]

In order to increase the density and reliability of floppy disks, in addition to improving the performance of the medium and magnetic head, it is also necessary to minimize the separation distance between the medium and magnetic head, and to ensure that the head runs stably. It is necessary to guarantee physical durability. For this purpose, the magnetic head of the present invention is a magnetic head for a double-sided floppy disk device in which two sliders each having a magnetic core are arranged facing each other, and the magnetic core surface of each of the opposing sliders is substantially spherical. Alternatively, by forming a spheroidal surface, the spacing between the head and the medium can be controlled to be small. In addition, by providing a concave portion or a chamfered groove on the slider surface facing the magnetic core surface, the medium itself acts as a soft pad without directly colliding the magnetic core surface with the opposing hard slider surface. .

This prevents the head from damaging the medium surface and improves password durability. Furthermore, since a pad is not used on the opposing surface of the magnetic core unlike a single-sided magnetic head, deformation over time can be prevented. By providing a concave surface on the slider surface, if dirt or abrasion powder that causes damage to the medium gets into the magnetic core area, the dirt will be removed from the concave surface or groove, which is advantageous for passware durability. It is. Furthermore, by making the magnetic core surface spherical or ellipsoidal, head touch is improved and recording density characteristics are also improved.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing a first embodiment of the present invention. Note that FIG. 1 shows a side cross section including the apex of the magnetic core in a state where a medium 100, which is a floppy disk, is sandwiched between two sliders. In the magnetic head shown in FIG.
The slider 11 has a columnar shape with one end being flat and the other end being spherical. The spherical portion of the slider 11, that is, the magnetic core surface LLB, and the columnar portion of the slider 11 are formed by the magnetic core IIA. And this magnetic core I
The inside of the IA is hollow. This magnetic core IIA
A coil 15 is attached so as to sandwich it. Further, a flat portion of the slider 11, that is, a flat portion 11C is attached to one surface of a plate-shaped gimbal 12.

On the other hand, the slider 13 is hollow inside.

One end of the slider 13 is in a flat state,
The other end is open. A flat portion of the slider 13, that is, a flat portion 13A, is provided with a concave portion 13B polished into a spherical shape. Furthermore, this slider 1
The other open end of the slider 13 is attached to one surface of the gimbal 14 such that the concave surface portion 13B of the slider 13 faces the magnetic core surface 11B of the slider 11.

The medium 100 is sandwiched between the slider 11 and the slider 13.

In such a magnetic head, by making each magnetic core surface of the opposing slider substantially spherical, it is possible to control the spacing between the head and the medium to be small. Further, by providing a concave portion on the slider surface facing the magnetic core surface, the medium itself acts as a soft pad without causing the magnetic core surface to directly collide with the opposing hard slider surface. This prevents the head from damaging the medium surface and improves the durability of the busware. Furthermore, since a pad is not used on the opposing surface of the magnetic core unlike a single-sided magnetic head, deformation over time can be prevented. By providing a concave surface on the slider surface, if dust or abrasion powder that causes damage to the medium gets into the magnetic core region, the dust or the like will be removed to the concave surface, which is advantageous for passware durability. Furthermore, by making the magnetic core surface spherical, head touch is improved and recording density characteristics are also improved.

FIG. 2 is a diagram showing a second embodiment of the present invention. Note that FIG. 2 shows a cross section in the radial direction of the medium including the apex of the magnetic core with the medium 100, which is a floppy disk, being sandwiched between two sliders.

In the magnetic head shown in FIG. 2, the slider 21 has a columnar shape, and the inside of the slider 21 is hollow with an open portion. The open portion of the slider 21 is attached to one surface of the gimbal 24. This slider 21 has two parts. A magnetic core 22 having a coil 23 is provided in the slider portion 21A, which is one portion. The portion where this magnetic core 22 appears on the surface of the slider portion 21A and its surrounding portion, that is, the magnetic core surface 21A1, is a spherical surface, and the radius of the spherical surface is 30 am. The other slider section 2
1B is provided with a concave portion 21B. This concave portion 21B+ is formed by polishing the slider portion 21B into a spherical shape, and has a depth of 0.5 sa+.

On the other hand, the slider 25 is also similar to the slider 21. That is, the slider 25 consists of two slider parts 25A and 25B, and the slider part 25A has a coil 27.
A magnetic core 26 is provided. Further, the slider portion 25A has a spherical magnetic core surface 25A.

The slider portion 25B has a concave portion 25Bl polished into a spherical shape. The magnetic core surface 25A1 of the slider 25 is the concave surface portion 21B of the slider 21.

The open portion of the slider 25 is attached to one surface of the gimbal 28 such that the concave portion 25BI of the slider 25 faces the magnetic core surface 21A1 of the slider 21.

The medium 100 is sandwiched between the slider 21 and the slider 25.

In such a magnetic head, by making each magnetic core surface of the opposing slider substantially spherical, it is possible to control the spacing between the head and the medium to be small. Furthermore, by providing a concave surface on the slider surface facing the magnetic core surface, the medium itself acts as a soft pad without causing the magnetic core surface to directly collide with the opposing hard slider surface. This prevents the head from damaging the medium surface and improves password durability. Furthermore, since a pad is not used on the opposing surface of the magnetic core unlike a single-sided magnetic head, deformation over time can be prevented. Note that by providing a concave portion on the slider surface, when dust or abrasion powder that causes damage to the medium gets mixed into the magnetic core region, the dust is removed from the concave surface, which is advantageous for passware durability. Furthermore, by making the magnetic core surface spherical, head touch is improved and recording density characteristics are also improved.

FIG. 3 is a diagram showing a third embodiment of the present invention. Third
The magnetic head shown in FIG. 3(a) includes a slider as shown in FIG. 3(b).

As shown in the perspective view of FIG. 3(b), this slider is a twin-body type slider having a groove 35A in the center. A magnetic core 35B was sandwiched between one side of this twin-barrel slider, and the slider surface was an ellipsoid. A groove 35C is formed and chamfered on the other slider surface of the twin-barrel slider.

Such a slider is used in the magnetic head shown in FIG. 3(a).

As shown in FIG. 3(a), in this magnetic head, a slider 31 is attached to a gimbal spring 32. Further, a slider 33 is attached to a gimbal spring 34. At this time, the position of the groove 33C of the slider 33 is the magnetic core gap 311 of the opposing slider 31).
correspond to

The medium 100 is sandwiched between the slider 31 and the slider 33.

In such a magnetic head, by forming each magnetic core surface of the opposing slider into a spheroidal surface, it is possible to control the spacing between the head and the medium to be small. Furthermore, by providing a chamfered groove on the slider surface facing the magnetic core surface, the medium itself acts as a soft pad without directly colliding the magnetic core surface with the opposing hard slider surface. This prevents the head from damaging the medium surface and improves password durability. Furthermore, since a pad is not used on the opposing surface of the magnetic core unlike a single-sided magnetic head, deformation over time can be prevented. Note that by providing grooves on the slider surface, if dust or abrasion powder that causes damage to the medium gets mixed into the magnetic core region, the dust or the like will be removed in the grooves, which is advantageous for passware durability. Furthermore, by making the magnetic core surface elliptical, head touch is improved and recording density characteristics are also improved.

FIG. 4 is a perspective view of one slider of a magnetic head according to a fourth embodiment of the present invention. This slider has a groove 4 in the center.
It is a twin body type slider with 1. One side of this twin-body type slider has a magnetic core 4 having a magnetic core gap 42A.
2, and the slider surface is an elliptical surface. On the other side of the twin body, a groove 43 is formed parallel to the central groove 41 and chamfered to form a recess. This is done so that the magnetic core 42 corresponds to the groove 43 of the slider facing the slider.
A magnetic head is formed in the same manner as in the second embodiment.

Using the magnetic head of the first to fourth embodiments and a floppy disk using a CoCr film as a medium,
We conducted a passware durability test.

The gap length of the core of the magnetic head is 0.25 μm. The floppy disk uses a polyimide film (thickness 30 μm) as the base film, and coats CoC on both sides.
Using r-alloy as a target, the thickness is 3 by sputtering.
000 CoCrTa thin films were formed. As for magnetic properties, saturation magnetization, perpendicular coercive force, and perpendicular magnetic anisotropy are 450ea+u/cc, 9000e, and 5 KOe, respectively.
It is. A carbon protective film having a thickness of 200 mm was formed on this magnetic layer by sputtering using carbon as a target. After processing this into a disk with a diameter of 3.5'', a lubricant was applied.

After a medium is installed in a floppy disk device having such a magnetic head and a signal is recorded, the signal is read out on the same track with the head loaded, and the head is operated until the playback output drops to 70% of the initial value. Number of sliding movements (
The sliding durability) was measured and the results are shown in Table 1.

Table 1 Table 1 shows relative values based on values measured for bus wear durability on the same CoCr film floppy disk using a conventional double-sided magnetic head as a comparative example. From Table 1, it is clear that this example has superior durability compared to the conventional example.

In addition, Table 1 shows the recording density characteristics measured with the head of the example and the head with a conventional shape, which is 1/2 of the solitary wave output value.
The recording density D50 was shown as follows. The unit is flux change per inch (PCI). From Table 1, it is clear that this example has better recording density characteristics than the conventional example.

〔Effect of the invention〕

As explained above, the magnetic head of the present invention has the effect of significantly improving sliding durability compared to conventional magnetic heads, and also has the effect of making it possible to obtain a magnetic head with excellent high-density characteristics. There is.

[Brief explanation of drawings]

FIG. 1 is a side cross-sectional view including the cap apex of a magnetic core showing a first embodiment of the present invention. FIG. 2 is a front cross-sectional view including the cap apex of a magnetic core showing a second embodiment of the present invention. FIG. 3 is a diagram showing a third embodiment of the present invention, and FIG.
Figure (a) is a perspective view showing one slider, Figure 3 (b)
4 is a perspective view showing one slider of the fourth embodiment of the present invention; FIG. 5 is a diagram showing an example of a conventional single-sided magnetic head and a medium; FIG. 6 is a diagram showing an example of a conventional double-sided magnetic head and a medium, and FIG. 7 is a perspective view showing an example of a slider of the double-sided magnetic head of FIG. 11...Slider 11A...Magnetic core 11B...Magnetic core surface 11C...Flat part 12, 14...Gimbal 13...Slider 13A...Flat part 13B... Concave portion 15... Coil

Claims (1)

[Claims] (1) In a magnetic head for a magnetic disk device in which two sliders, at least one of which has a magnetic core, are disposed facing each other, the magnetic core surface of the slider having the magnetic core has a substantially spherical surface and a spheroidal surface. 1. A magnetic head characterized in that the other slider is provided with either a concave portion or a groove having a chamfered edge on the surface of the other slider.