JPH03212853A - Both-side type magnetic head for flexible disk - Google Patents

Abstract

PURPOSE:To prevent a flaw from occurring on a head or a medium by specifying a ratio of the length of a sliding plane to the height of a slider. CONSTITUTION:The height of the slider 1 is defined as (h), and the length of the sliding plane as (l), and a ratio l/h is set at >=2.5. When the height (h) of the slider is, for example, decreased, the length (l) of the slider is set at the same length 5mm as that of the one in current use, and (h) at 1.7mm, and the value of l/h at 2.94. Also, when the length (l) of the slider is increased, the height (h) is set at the sme height 2.6mm as that of the one in current use, and (l) at 7mm, and l/h at 2.69. In such a manner, it is possible to decrease the force of the leading edge of the head to be pushed in a medium plane, and to remarkably reduce the occurrence of the flaw on the medium or the head.

Description

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

[Conventional technology]

In a double-sided flexible magnetic disk device, a double-sided magnetic head as shown in FIG. 5 is used to perform magnetic recording and reproduction on a magnetic layer formed on an organic film such as PET. FIG. 5(a) is a perspective view of the magnetic head seen from the slider side;
FIG. 5(b) is a side view of the double-sided magnetic head. The magnetic herad core that performs recording and playback is built into Nirail's slider 1, and the slider is attached to a gimbal 2 made of thin stainless steel or phosphor bronze. The periphery of the gimbal is attached to the head carriage, and the pivot 3 is placed in the center, limiting the degree of freedom of the slider movement to only rotational movement around the pivot. Moreover, the rotational movement is also limited to a minute area by the gimbal spring. This structure allows the spacing between the head and the medium 4 to be small and stable.

The flexible magnetic slider currently in use has a height of about 2.7 mm and a length of about 51111 mm.

[Problem to be solved by the invention]

In flexible disk devices currently in use, if the medium is used for a long period of time, the head and medium may become scratched, resulting in a significant drop in playback output, and the device may no longer function. When we examine heads with such scratches, we find that most of them are scratched on the leading edge. This is thought to be because the slider receives a moment due to sliding friction when it travels, and as shown in FIG. 6, the leading edge takes a thrusting position, and the force is concentrated there. In Figure 6, the height of slider I is h, and the length of the sliding surface is! It is shown in

SUMMARY OF THE INVENTION An object of the present invention is to provide a double-sided magnetic head for a flexible disk in which the force with which the medium is pushed is reduced and the head and medium are less likely to be scratched.

[Means to solve the problem]

The present invention provides a double-sided magnetic head for a flexible disk in which, when the height of the slider is h and the length of the sliding surface is l, I! , /h is 2.5 or more.

[Operation] Calculate the force with which the leading edge pushes the media surface. Ignoring the gimbal effect and assuming that the frictional force received from the medium 4 is F as shown in FIG. 7, the resulting moment is M=Fh (1). The force f1 with which the leading edge pushes the medium is ! becomes. Assuming that F=5 g f, and plotting f against l/h, the result is as shown in Fig. 8. In the current double-sided magnetic head for flexible disks, h = 2.6 m.
m, E = about 5 mm, and ff/h is 2.
08 is the point indicated by the black circle in the figure. From the figure, it can be seen that by increasing ρ/h, the pushing force is significantly reduced and improved.

Therefore, in the present invention, 1. By setting /h to 2.5 or more, the force with which the leading edge of the head pushes against the medium surface can be reduced, and the occurrence of scratches on the medium and head can be significantly reduced.

〔Example〕

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

FIG. 1 shows an embodiment in which the height h of the slider is reduced. The length of the slider is 5m, the same as the current one.
m and h is 1.7 mm. The value of 2/h is 2.
It is 94.

FIG. 2 shows an embodiment in which the slider length l is increased. The height h was set to 2.6 mm, which is the same as the current one, and height h was set to 7 mm. f/h is 2.69.

Figure 3 shows the conventional slider used for comparison, h = 2
．． 6mm, l = about 5mm, f/h = 2.0
It is 8.

All of them were mounted on the same gimbal, and since some were at different heights, I installed them so that the gimbal was parallel to the medium when the head was loaded.

Figure 4 shows the evaluation results of passware durability.

A CoCr sputtering medium was used as the medium, and the rotation speed was 60 Orr.
Evaluation was made in pm. The point at which the output dropped to 70% of the initial value was defined as passware durability. Three samples each were evaluated. The conventional type has about 10 million busses, while the one with h=1.7mm has about 30 million busses, I! , = 7 mm, passware durability of about 25 million buses was obtained.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to provide a double-sided magnetic head for a flexible disk that hardly damages the medium.

[Brief explanation of drawings]

Fig. 1 shows the shape of an embodiment realized by reducing the height of the slider, Fig. 2 shows the shape of an embodiment achieved by elongating the slider, and Fig. 3 shows the shape of a conventional slider. Figure 4 is a diagram showing the pathware durability for each slider shape, Figure 5 is a diagram showing the configuration of a flexible disk double-sided magnetic head, and Figure 6 is a diagram showing the posture of the head when the medium is running. Figure 7 is a diagram for calculating the force that the leading edge pushes into the medium surface, and Figure 8 shows the force f that the leading edge pushes into the medium. It is a figure which shows the calculation result of f/h dependence of. 1... Head slider 2... Gimbal 3... Pivot 4... Medium

Claims (1)

[Claims] (1) Double-sided magnetic head for flexible disks, characterized in that l/h is 2.5 or more, where h is the height of the slider and l is the length of the sliding surface. Double-sided magnetic head.