JPS5912757Y2 - magnetic head - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to the structure of a magnetic head in magnetic recording.

As shown in FIG. 1, magnetic recording is performed with the recording medium 3 and the magnetic head 1 in contact with each other or with an appropriate gap maintained between them.

The magnetic head 1 includes a slider 2 whose purpose is to maintain stable contact or a gap with a recording medium 3, a core 4 whose purpose is to magnetize a storage pattern on the recording medium 3, or to continue a magnetized storage pattern. The coil unit 5 converts the electric signal into a magnetic signal during recording, and converts the magnetic signal into an electric signal during continuation.

Traditionally, Hermalloy and Ni-Zn7 have been used as materials for the core 4.
elite and Mn-Zn ferrite were used.

In magnetic heads, the coil is generally wound only around the core, or a coil is inserted into the core.

There is no problem if the core is an electrical insulator, but
If the conductor has a specific resistance of several tens of ohms or less, the coil and core must be insulated.

For example, it is said that an insulating sheet is placed in the winding section (coil insertion section) and a coil wound around a bobbin is inserted into the core.

Recently, recording densities have been increasing more and more, and Mn--Zn ferrite, which has excellent magnetic properties, is being seen as a promising core material.

However, since Mn-Zn ferrite has a very low specific resistance of several ohms, an insulating sheet or the like must be placed at the coil location.

However, as magnetic heads become more sophisticated, they are becoming smaller and lighter, and methods such as placing an insulating sheet at the coil position or winding the coil around a bobbin are becoming difficult.

Furthermore, there is a risk that the insulating sheet may shift or fall short through the core due to pinholes, which is undesirable from a reliability standpoint.

An object of the present invention is to provide a core that uses Mn-Zn ferrite with excellent magnetic properties and does not require insulation treatment.

A magnetic head records a magnetic pattern on a recording medium using magnetic flux leaking through a gap of 1 to several microns called a gap in the core portion.

Recently, as recording densities have been increasing, the coercive force Hc of recording media has tended to increase.

It is known that the contact depth of the gap is usually about 10 μm to several 100 μm, and that during recording, this gap portion has a very high magnetic flux density.

In order to magnetize such a recording medium with a high coercive force, a core material with a higher magnetic permeability is advantageous, and Mn--Zn ferrite is now being seen as promising.

However, since Mn--Zn ferrite has a low specific resistance of several ohms (1), it is necessary to insulate the coil portion.

In the present invention, a high magnetic permeability material Mn-
The reason is that Zn ferrite is used and Ni--Zn ferrite is placed in the winding portion, making insulation treatment unnecessary.

Even if NiZn ferrite is used in the winding part, the cross-sectional area of the magnetic circuit can be made much larger than the gap part, and even if Ni-Zn ferrite, which has magnetic properties inferior to Mn-Zn, is used, the performance of the magnetic head can be improved. , it is possible to obtain the desired characteristics without any damage.

FIG. 2 shows an example of a conventional magnetic head core in which Ni--Zn ferrite is used for the core portion 6 and the winding portion core 7. As shown in FIG.

In this case, the core used for the winding portion core 7 is an insulator, and the coil 5 can be directly wound around the core 7.

FIG. 3 shows an example of a core using Mn-Zn ferrite.

Since Mn--Zn ferrite is used for the core 8 and the winding core 9, an insulating sheet 10 must be inserted between the core 9 and the coil 5.

FIG. 4 shows an embodiment of the invention.

By using Mn-Zn ferrite with excellent magnetic properties for the core 8 and using Ni-Zn ferrite with high specific resistance for the winding core 7, there is no need for insulation between the core and the coil. It becomes possible to manufacture a magnetic head using ferrite.

The core and coil are essential components in a magnetic head, and as performance increases in the future, a material with higher magnetic permeability is desired for the core material.

According to the present invention, it is possible to use Mn--Zn ferrite having high transmittance without insulation treatment, and it is expected that the magnetic head will be lighter and smaller and the reliability of insulation will be improved.

[Brief explanation of the drawing]

Fig. 1 is a side view, partially transparent, showing the shape of a general magnetic head, Fig. 2 is a perspective view showing an example of a core using conventional Ni-Zn ferrite, and Fig. 3 is a conventional Mn-Zn ferrite core. Z
A fourth perspective view showing an example of a core using n-ferrite.
The figure is a perspective view showing an example of a core according to the present invention. 5... Coil, 7... Winding core,
8...U-shaped core, 11...gap.

Claims (1)

[Scope of utility model registration request] In a magnetic head in which a closed-loop magnetic circuit is constructed by butting magnetic cores, one of the magnetic cores to which a winding is applied is made of Ni-Zn ferrite, and the other magnetic cores are made of M.
A magnetic head characterized by using n-Zn ferrite.