JPH06333207A - Magnetic head - Google Patents

Abstract

(57) [Abstract] [Purpose] The wear of the magnetic head due to contact with the magnetic tape is reduced, and the non-magnetic material and the magnetic ferrite have the same grindability, which eliminates steps during head processing and improves performance. It is an object of the present invention to provide a simple magnetic head. [Structure] Magnetic core halves 3 and 4 composed of an auxiliary core 1 and a metal magnetic film 2 are butted against each other with their end faces facing each other, and a magnetic gap 5 is formed at the butted faces of these metal magnetic films. In the magnetic head, the sliding surfaces 3a and 4a of the magnetic recording medium of the auxiliary core are Ni-Zn ferrites which have no magnetism at room temperature, and the other magnetic path portions 3b and 4b are magnetic Mn-Zn ferrites. Characterize.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head for magnetic recording and reproduction of a video tape recorder or the like.

[0002]

2. Description of the Related Art In recent years, in the field of magnetic recording / reproducing devices such as video tape recorders, in order to record a large amount of information with the development of digital recording technology,
Recording and reproduction with higher density are desired. Therefore, in the magnetic tape which is a magnetic recording medium, a metal tape having a high coercive force is used, and the relative speed between the magnetic tape and the magnetic head is also increased.

Mn-Zn ferrite having a good magnetic permeability is used for the magnetic head core portion, but the wear of the ferrite caused by the contact with the magnetic tape becomes a serious problem in the portion corresponding to the sliding surface. Therefore, in a magnetic head having a structure in which a metal magnetic film is used as a magnetic core, there is also a purpose of solving a pseudo gap, and a non-magnetic material having good wear resistance such as titanate ceramics or hematite is used for the sliding surface. In the magnetic path portion near the wire window, it is necessary to construct a magnetic head using Mn-Zn ferrite having magnetic characteristics, and a pair of magnetic core halves in which a nonmagnetic material and ferrite are integrated by glass bonding. A technique for producing a magnetic head by using has been generated.

[0004]

By the way, since non-magnetic materials such as titanate-based ceramics and hematite have poor grindability, the productivity of the magnetic head deteriorates. Further, since the non-magnetic material and the ferrite have different grindability, a step is formed during head processing.

Therefore, Zn, which has good grindability, is used as a non-magnetic material.
Ferrite or Mn-Zn ferrite that does not have magnetism at room temperature is integrated with the magnetic Mn-Zn ferrite of the core and used as a magnetic core half body, but the wear resistance of the non-magnetic material is the same as that of the magnetic Mn-Zn ferrite. It is only a degree and cannot be improved.

The present invention has been proposed in view of such a conventional situation, and reduces wear of a magnetic head due to contact with a magnetic tape, and makes a non-magnetic material and a magnetic ferrite have the same grindability. Therefore, it is an object of the present invention to provide a high-performance magnetic head by eliminating a step during head processing.

[0007]

Means for Solving the Problems As a result of intensive studies for achieving the above-mentioned object, the present inventors have integrated a Ni—Zn ferrite and a magnetic Mn—Zn ferrite which have no magnetism at room temperature into one body. The inventors have found that a high-performance magnetic head can be manufactured by using the magnetic core half body, and have completed the present invention.

According to the present invention, the magnetic core halves composed of the auxiliary core and the metal magnetic film are butted against each other with their end faces facing each other, and a magnetic gap is formed at the butted faces of these metal magnetic films. In the magnetic head,
It is characterized in that the sliding surface of the magnetic recording medium of the auxiliary core is made of Ni-Zn ferrite which does not have magnetism at room temperature, and the magnetic path portion other than that is made of magnetic Mn-Zn ferrite.

[0009]

The present invention comprises a magnetic core half body in which a Ni-Zn ferrite which does not have magnetism at room temperature is integrated on the sliding surface of the magnetic recording medium and the other magnetic path portion is integrated with the magnetic Mn-Zn ferrite. By using Ni—Zn ferrite for the sliding surface of the magnetic recording medium, the wear of the magnetic head due to contact with the magnetic recording medium is reduced, and the Ni—Zn ferrite not having magnetism at room temperature is used. Magnetic Mn-
By making the grindability of Zn ferrite the same, it is possible to eliminate steps during head processing and improve head life without degrading productivity.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments to which the present invention is applied will be described in detail below with reference to the drawings. As shown in FIGS. 1A and 1B, in the magnetic head as an example of the present embodiment, the magnetic core halves 3 and 4 composed of the auxiliary core 1 and the metal magnetic film 2 serving as the magnetic core are metal magnetic. The end faces of the film 2 are made to face each other and are abutted against each other, and a magnetic gap 5 is formed on the abutting face of these metal magnetic films 2.

The auxiliary core 1 is composed of an I-shaped magnetic core half body 3 and a C-shaped magnetic core half body 4 having a winding window 6 which are joined together by a fused glass 7. The feature of the present invention is that the magnetic recording medium sliding surfaces 3a, 4a of the auxiliary core 1 are made of Ni that does not have magnetism at room temperature.
-Zn ferrite, and the other magnetic path portions 3b, 4b are made of magnetic Mn-Zn ferrite.

That is, the auxiliary core composite material 10 processed into the auxiliary core 1 is, as shown in FIG. 2, a non-magnetic material 11 made of Ni--Zn ferrite which is not magnetic at room temperature,
The soft magnetic material 12 made of magnetic Mn-Zn ferrite is integrally manufactured by the fused glass 8. The auxiliary core composite material 10 is shown in FIGS. 1 (A) and 1 (B).
Processing is performed on the I-type magnetic core half 3 and the C-type magnetic core half 4 having the winding window 6.

As an embodiment of the present invention, the non-magnetic material 11 of
Ni-Zn ferrite Each raw material is Fe ₂O₃: 50 mol
%, ZnO: 39 mol%, NiO: 11 mol%
Wet mixing to achieve a reaction at 900 ° C in the atmosphere
After that, add a binder to make it into a predetermined shape at 100 MPa.
It was molded and fired at 1200 ° C in consideration of equilibrium oxygen pressure. Production
The Ni-Zn ferrite has a Tc of -30 ° C and is at room temperature.
Is non-magnetic.

Next, Mn-Z of the soft magnetic material 12 shown in FIG.
Fe ₂ O ₃ : 52 mol%, Zn
O: 20 mol% and MnO: 28 mol% were reacted and molded in the same manner as above, and calcined at 1250 ° C. in consideration of equilibrium oxygen pressure.

After processing the non-magnetic material 11 and the soft magnetic material 12 to have a predetermined size, the non-magnetic material 11 and the soft magnetic material 12 were brought into close contact with each other via the fused glass 8 and integrated as shown in FIG.

The metal magnetic film 2 serving as the magnetic core is formed by sputtering a cobalt-zirconium-niobium alloy. The metal magnetic film 2 has a laminated structure of four layers having a thickness of 0.1 μm as an insulating film of silicon oxide, and the total thickness is 50 μm.

Thus, the magnetic head having the shape shown in FIG. 1 was manufactured. With respect to the above-mentioned magnetic head, the amount of wear was measured by running a magnetic tape using the magnetic metal powder at a relative speed of 6 meters per second under the conditions of 21 ° C. and 50% humidity. The results are shown in Fig. 3.

As Comparative Example 1, the nonmagnetic material 11 of FIG.
The wear amount was measured under the same conditions as in the example using the magnetic head manufactured by the above method using n-ferrite. As Comparative Example 2, the wear amount was measured under the same conditions as in the example using a magnetic head of the same shape composed of an auxiliary core using calcium titanate as the non-magnetic material 11 in FIG.

As is apparent from FIG. 3, in the magnetic head according to the present invention, the sliding surface is larger than that of Zn ferrite.
It can be seen that the amount of wear due to sliding with the magnetic tape was reduced, and the sliding surface exhibited wear resistance equivalent to that of calcium titanate. Further, there is no step due to the processing of the non-magnetic material and the magnetic material, and the precision workability is the same as that of the conventional magnetic head using Zn ferrite as the sliding surface, and the manufacturing yield and the productivity were not reduced.

[0020]

As is apparent from the above description, in the present invention, the auxiliary core is made of a non-magnetic material having good wear resistance for the sliding surface of the magnetic recording medium and a material having excellent magnetic characteristics for the magnetic path portion. Can be used to manufacture a magnetic head with high productivity and long life.

[Brief description of drawings]

FIG. 1 is a magnetic head of the present embodiment, FIG. 1 (A) is a top view thereof, and FIG. 1 (B) is a perspective view thereof.

FIG. 2 is a composite material substrate diagram for an auxiliary core of the magnetic head of this embodiment.

FIG. 3 is a wear comparison graph of this example and a comparative example.

[Explanation of symbols]

 1 Auxiliary Core 2 Metal Magnetic Film 3 I-type Magnetic Core Half 4 C-type Magnetic Core Half 3a, 4a Magnetic Recording Medium Sliding Surface 3b, 4b Magnetic Path Part 5 Magnetic Gap 6 Winding Window 7, 8 Fused Glass 10 Composite material for auxiliary core 11 Non-magnetic material 12 Soft magnetic material

Claims (1)

[Claims] 1. A magnetic head in which magnetic core halves composed of an auxiliary core and a metal magnetic film are butted against each other with their end faces facing each other, and a magnetic gap is formed at the butted faces of these metal magnetic films. 2. The magnetic head, wherein the magnetic recording medium sliding surface of the auxiliary core is made of Ni—Zn ferrite which does not have magnetism at room temperature, and the magnetic path portion other than that is made of magnetic Mn—Zn ferrite.