JPS58128018A - Magnetic head - Google Patents

Abstract

PURPOSE:To prevent the end of a magnetic core from being opened into sector shape after shaping and to attain accurate track size, by laminating a plurality of the 1st high permeability thin plates having comparatively thin thickness and providing the 2nd high permeability thin plate having thick plate thickness at least on one surface. CONSTITUTION:A magnetic head is formed by using a magnetic core in which the 1st high permeability thin plates having comparatively thin plate thickness are laminated for the plurality and the 2nd high permeability thin plate having comparatively thick plate thickness is provided on at least one surface. In Figure, 6 is an Sendust material, about 100mum in thickness, 7 is an amorphous alloy laminating about ten amorphous members, about 30mum in thickness, and 8 is a core holding member made of zinc die casting. Since the shaping characteristic of the member 6 is very similar to that of the alloy 7, the disturbance of the flat plane of the processed surface due to shaping is not caused. Since the member 6 has similar wear characteristics as those of the alloy 7, the wear becomes uniform, allowing to avoid the spacing loss of the head.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic head in which a magnetic core is formed of a plurality of high permeability thin plates having mutually different properties.

Conventionally, high magnetic permeability thin plates such as sendust materials, permalloy materials, and amorphous alloys have been used as core materials for magnetic heads that enable information to be recorded and reproduced on high coercive force tapes such as metal tapes. However, all of these core materials have the following drawbacks:
The saturation magnetic flux density is large, but because it is difficult to process thin plates: the number of laminated sheets in 1A is @f, and the island frequency characteristics are not good. In addition, since it is easy to process thin sheets of permed steel, it is possible to stack multiple layers, but the saturation magnetic flux density is comparable to Sendust material (Bs -8000G to 9000G).
K Regarding the permalloy alloy composition, the high frequency characteristics are significantly worse than normal permalloy materials. Furthermore, the abrasion resistance is inferior to Sendust material, which has been a problem. In view of the above points, today, amorphous materials have the high frequency characteristics of metal tapes, and are extremely easy to make into thin sheets, and thin sheets having a thickness of 20 to 5 degrees are usually manufactured. It also has extremely high specific resistance (and excellent high frequency characteristics).

Furthermore, amorphous materials have extremely high hardness and poor wear resistance. However, due to manufacturing, the precision of the thin plate surface is poor and
The thin plates are extremely thin and have low peel strength after lamination. The low peel strength of the core laminate becomes a problem when the front ear surface is ground in the manufacturing process of the Mori head. Figure 1 (perspective view) shows a half core assembly when using a conventional laminated core.
FIGS. 2(a) and 2(b) are views of the main parts of FIG. 1 as viewed in the direction of arrows A and B. In the figure, 1 is a thin plate laminated core, 2 is a core holder, 5ffi winding section, and 4 is a terminal section.

Generally, in a structure in which the laminated core 1 protrudes more than the core holder 2 in the sliding movement with the recording medium and the core holder does not cover the sliding surface with the recording medium, when the thickness of the thin plate is 50 μm or less, the grinding process Later, as shown in FIG. 1(b), the end of the processed core opens into a fan shape. This is thought to be because the thin plates are extremely thin, which weakens the strength of each thin plate, and further reduces the peel strength by 1. In particular, in the grinding of the grinding portion 5 for determining the depth d of the zeyap shown in FIG. 2(a), the largest layer-like opening (

The flatness of the yag deteriorates, the effective gap opens, and the track dimensions no longer match the predetermined dimensions. In order to prevent such drawbacks, the first method is to create a structure in which both front surfaces of the core 1 are sandwiched between the core holder 2, as shown in Figs. 3(a) and (b).
There is a way to create a structure like this. In this method, since the holding body 2 has a structure in which both sides of the front part of the core 1 are completely reinforced, even if the grinding to determine the depth d (see Fig. 2 (1)) is performed, There is no chance of the thin plates peeling off from each other. However, in this structure, the core holder 2 is exposed on the sliding surface with the recording medium. The core holding body is generally zinc-based,
JX having the structure shown in Fig. 3(a) and (bl) is not preferable because it uses a lot of cast iron and has poor corrosion resistance and corrosion resistance.

A second method is to increase the strength of the thin plates by increasing the thickness of each laminated thin plate.
With the current technology, it is extremely difficult to amorphize a core material having a thickness of 50 prn or more.

In order to eliminate the above-mentioned drawbacks, in the present invention, a plurality of thin first high magnetic permeability thin plates (Comparative 8) are laminated, and a plurality of thin first high permeability thin plates (comparison 8) are stacked on one side of the laminate. The magnetic head is constructed using a magnetic core provided with a flat thin plate of high magnetic permeability.

Hereinafter, the present invention will be described in detail with reference to Examples.

Figure 1.4 is a plan view showing the first embodiment of the present invention.
Figure 4 shows a plane similar to Figure 2 (b) and Figure 3 (b). Sendust material, an amorphous alloy made by laminating about 10 amorphous materials each having a thickness of about 60 μm (relatively thin) 7Fi thin plate, and 8 a core holder such as zinc die casting.

Sendust material °6 has high hardness and strong core strength, and can be made as thin as 100 mm using current technology.

Furthermore, since the sendust material 6 has extremely similar grindability to that of the amorphous alloy 7 during grinding, no disturbance of the plane of the machined surface occurs due to grinding.

Furthermore, since the sendust material 6 has the same properties as the amorphous alloy 7 with respect to a recording medium (for example, a magnetic tape), the abrasion becomes uniform and the head becomes smeared.

On the other hand, permalloy materials have a large hardness difference with amorphous alloys,
The precision of the ground surface is poor, making it difficult to process the gap accurately.

Next, a second embodiment of the present invention is shown in diagram m5. The second embodiment uses a smaller number of sendust materials, which are difficult to process.Generally, in a head with multiple channels, a magnetic contact plate is connected to each core in order to reduce crosstalk between each channel. In addition, in order to improve the characteristics of the magnetic abuse plate Fi*i, it is necessary to expose the end portion to the sliding surface with the four bodies mentioned above, as well as the core. If a fixing resin is impregnated between the core and the magnetic massing plate in the fixing process and the core is integrated, the amorphous core material will not peel off on the magnetic massaging plate side even if the above-mentioned grinding is performed. In a head with multiple magnetic core channels using a 6-layer plate, one layer of Sendust thin plate is 100KN on one side of each core, and the other side has a magnetic conduction layer through a non-magnetic material. In other words, in No. 51; In order to prevent magnetic short circuits, a non-magnetic plate made of phosphor bronze or Yoji steel with a thickness of about 100 μm is used.No. 11 has a thickness of about 30 μm.
12 is a sendust thin plate having a thickness of about 100 tones, and 16 is a core holder.

As described above, the uninvented magnetic head has a plurality of first high-permeability thin plates that are relatively thin, and a plurality of first thin plates with high magnetic permeability that are relatively thin are laminated, and a second thin plate that is relatively thick is opened on one side of the laminated body. There is no problem and accurate track dimensions can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a half-section of the core assembly of a conventional magnetic head. FIG. 3 (4) is an am@ side view of a magnetic head in which the end surfaces of the core holder and the magnetic core are on the same plane. Fig. 3(b) is a plan view of the main part of the magnetic head with the end faces of the Fi-fa holder and the magnetic core facing the same direction, Fig. 4 is a plan view of the main part of the first embodiment of the present invention, and Fig. 5 is the main part of the magnetic head. FIG. 4 is a plan view of main parts of a second embodiment of the invention. 9-・・・Magnetic tactile plate, 10#@Oe non-magnetic plate, 11
Society: Amorphous magnetic alloy thin plate, 12: 0 Sendust thin plate, 13@: Core holder. Patent applicant: Canon Electronics Co., Ltd.

Claims (1)

[Claims] (1) A magnetic core comprising a plurality of first high magnetic permeability thin plates having a relatively thin plate thickness, which are laminated together, and a second high magnetic permeability thin plate having a relatively thick plate thickness provided on at least one surface of the laminate; A magnetic head characterized by having a magnetic core and a winding portion wound around the magnetic core. (2) A magnetic head according to claim (1), characterized in that the first thin plate of high magnetic permeability of the magnetic core is made of an amorphous magnetic alloy, and the second thin plate of high magnetic permeability is made of sendust material.