JPH0258710A - Magnetic head - Google Patents

Abstract

PURPOSE:To cause a central magnetic core and magnetic cores on both sides of the central core to independently record/reproduce different signals, respectively, without crosstalk by magnetically and electrically shielding magnetic paths of the three magnetic cores by means of nonmagnetic conductors and the notched section of each magnetic core. CONSTITUTION:Three magnetic cores 11-13 respectively composed of left and right core half bodies 11a-13a and 11b-13b are joined together with nonmagnetic conductors 9 in between and three gaps 4, 6, and 8 are formed. Of the three gaps 4, 6, and 8, the gaps 4 and 8 are respectively used for recording/ reproducing one field of video signals constituting one frame of still picture and the central magnetic tap 6 is used for recording/reproducing sound signals. Winding windows 11d, 12d, and 13d are formed in the core half bodies 11b, 12a, and 13b and notched sections 11c, 12c, and 13c, each of which is formed by shaving off the rear side from the sliding surface side, are installed to the half bodies 11a, 12b, and 13a. Therefore, the central and side cores on both sides can separately record/reproduce different signals without crosstalk.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a magnetic head, and particularly to a magnetic head in which a coil winding is applied to a winding window of a magnetic core obtained by butt-joining core halves. It is.

[Prior Art] Conventionally, a thin film magnetic head or a bulk head has been used as a still video magnetic head for recording still image data. A thin film magnetic head is a magnetic head in which not only the magnetic material but also the coil portion is made of a thin film using a thin film deposition process, a photolithography etching process, etc., and has a configuration as shown in FIG. 6, for example.

In FIG. 6, reference numeral 61 is a substrate made of glass or the like.
A magnetic core made of a lower magnetic material and an upper magnetic material, a gap part and a coil part made of a conductive film are formed on this substrate by a thin film forming process, and an insulating layer 6 is formed on the substrate.
3, and a protective plate 64 is further bonded to the protective plate 64. The magnetic gap portion 62 is exposed between the substrate 61 and the protection plate 64.

On the other hand, the bulkhead has a structure as shown in FIG.

In FIG. 7, reference numerals 91 and 91 indicate core halves made of single-crystal ferrite or the like, and an alloy magnetic material 92 made of Sendust alloy having a high saturation magnetic flux density is provided at the joint portions of the core halves.

One of the core halves 91.91 is provided with a winding window 91a for later winding a coil. The core halves 91.91 are joined as blocks with an adhesive 93 made of glass or the like through a gap material, and then sliced to form a magnetic core as shown in FIG. The length of the magnetic gap 94 in the track width direction is determined by the shape of the grinding portion in which the adhesive 93 is embedded.

[Problems to be Solved by the Invention] In still video technology, it is conceivable to record and reproduce audio signals using guard band sections between tracks on which video signals are recorded. In this case, the conventional head shown in Figures 6 and 7 can only record and reproduce video signals, and in order to record and reproduce audio signals at the same time as video signals, it is necessary to record and reproduce audio signals simultaneously. However, since it would be unreasonable in terms of space to separate the head for audio signals and the head for video signals and place them in the recording area of the magnetic disk, it was necessary to have a head for audio signals and a head for video signals in the same Herad chip. It was necessary to provide a track for audio recording and playback.

However, in a thin-film head like the one shown in Figure 6, the conductor film that makes up the coil occupies a large space in the track width direction, so it is very difficult to form an audio head in the space between the tracks of a two-track thin-film head. This would be difficult and would require a significant increase in costs. Further, in the case of a bulkhead, coil winding is inevitably required, and because of this space, it is difficult to similarly provide an audio core within the same chip, and there is also the problem of crosstalk.

The object of the present invention is to solve the above-mentioned problems and to make it possible to record and reproduce multiple signals by providing a magnetic gap within the same Herad chip, which occupies a small space, without causing problems such as crosstalk. It is.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a magnetic head in which a coil winding is applied to a winding window of a magnetic core obtained by butt-joining core halves. In this method, three magnetic cores are laminated with a non-magnetic conductor in between, and winding windows are provided at approximately the same position on each core half of one of the magnetic cores on both sides sandwiching the central magnetic core. The winding windows of the central magnetic core are cut out so that they are independent of the magnetic path of the coil provided in the winding windows of the magnetic cores on both sides, and the winding windows of the central magnetic core are cut out so that the winding windows of the magnetic cores on both sides are It is provided on the core half on the opposite side, and the magnetic cores on both sides are cut out so that they are independent of the magnetic path of the coil provided in the winding window of the central magnetic core.

[Function] According to the above configuration, the magnetic paths of the three magnetic cores are magnetically and electrically interrupted by the non-magnetic conductor and the notch of each magnetic core, and the central magnetic core and the magnetic cores on both sides are connected to each other. It is possible to record and reproduce separate signals without crosstalk.

[Example] Hereinafter, the present invention will be described in detail based on the example shown in the drawings.

FIGS. 1 and 2 show a perspective view and a front view of a magnetic head on the medium sliding surface side, respectively, employing the present invention.

In the figure, reference numerals 11a to 13a and flb to 13b are core halves that constitute the bulkhead. In this embodiment, these left and right core halves 11a to 13a and 11b
Three magnetic cores consisting of ~13b are joined via a non-magnetic conductor 9 to form three gaps. Among the caps 4.6.8 of each core 11 to 13, the magnetic cap 4.8 is used for recording and reproducing video signals of one field each constituting one frame of a still image, and the magnetic gap 6 in the center is used for recording and reproducing audio signals. Used for recording and playback.

Next, M3 diagrams (A) to (C) show the three magnetic cores 11 to 13.
The structure of The core halves 11a, 112a and 13a are made of an alloy film 3.5.7 such as sendust and a gap material 4a,
6a, 8a to the other core half 11b, 12b, 1
3b via adhesive agent 2. This basic structure itself is the same as that of the conventional bulkhead shown in FIG. Winding windows 11d, 12d, and 13d are formed in the core halves 11b, 12a, and 13b for later coil winding.

However, as shown in the figure, the core halves 11a, 12b, and 13a have notches 11 that are largely cut away from the sliding surface side.
c, 12c and 13c are provided. These cutouts 110 to 13c are arranged in each magnetic core 11 as shown in FIG.
When connecting ~13, the central magnetic core 1 is connected by the coil.
This is to prevent magnetic coupling between the cores 2 and the magnetic cores 11 and 13 on both sides.

The shape of each notch 13c is approximately similar to the outer periphery of a core half whose medium sliding surface is ground into a cylindrical shape as shown in the figure. The angle θ formed by the side parallel to the gap plane of the notch and the plane parallel to the sliding surface is θ<jan'(R+7
〒]/L), and θ is 80 in this example.
°. As a result, when the gear tooth depth is 10 μ or more, the sliding area does not decrease, and by increasing θ to this extent, space for the winding can be secured. Also, the distance 11ttl between the side parallel to the gap plane and the gap plane is 150μ
It should be about m.

The magnetic cores 11 to 13 configured in this way are joined so that the magnetic gaps 4.6.8 are aligned in a straight line as shown in FIG. Central magnetic core 1 by applying wire
2 can simultaneously record and reproduce audio signals, and the magnetic cores 11 and 13 on both sides can simultaneously record and reproduce video signals one field at a time. The magnetic path of each core is formed by the notches 13c and the non-magnetic conductor 9.
Since it is electrically shielded, there is no problem with crosstalk.

Next, the manufacturing process of the above magnetic head will be described. First, the magnetic cores 11, 12 and 13 are constructed separately, but since the manufacturing process for these cores is almost the same, the manufacturing process for the magnetic core 11 will be illustrated here.

First, core half blocks that will become the core half bodies 11a and 11b are prepared, and a winding window li is placed in the block that will become the core half body 11b.
form d. Next, an alloy film 3.3 made of Sendust alloy with a thickness of about 20 μm is sputtered on the joint surface of each block, and then grooves for the adhesive 2 are formed on the sliding surface at intervals according to the thickness of the core. . By this groove processing, the track width is set to about 60 μm. Next, SiO was applied as a gap material to the joint surfaces of the core half blocks.
2 to a thickness of about 0.25 μm.

Next, these core halves are butted and joined together using an adhesive 2 made of low-melting glass having a working temperature of about 600 ℃, and after that, the notch 11c is ground and sliced to a predetermined thickness to form the magnetic core. Get 11. The thickness tl of the notch 11c from the joint surface (t2 in the case of the core half 12d) is approximately 150 μm. Thickness tl, t2 is 15
The reason why the thickness is about 0 μm is because the magnetic properties of the core deteriorate when the thickness is less than about 100 μm, and also to ensure space for the winding. For example, if a winding window with a width of 0.35 mm is provided, a winding space with a width of 0.2 mm is secured even after subtracting the core thickness (tl) of 0.15 n+m. Note that the angle formed by the two sides of the notch lie is determined by the above formula. Further, when slicing the core, it goes without saying that the cutting direction is set so that the angle formed by the core and the gap is perpendicular or has a predetermined azimuth angle.

The magnetic cores 12 and 13 are also manufactured by the same procedure as above, but a non-magnetic conductor made of beryllium kappa or the like is coated with a thickness of 10 μm on both sides of the central magnetic core 12, as shown in FIG. 1 or FIG. 3(B). form a degree.

Thereafter, each of the magnetic cores 11 to 13 is bonded using a low melting point glass whose working temperature is lower than that of the low melting point glass of the adhesive material 2. At this time, alignment is performed so that the magnetic gaps 4.6.8 are aligned substantially on a straight line.

Subsequently, coils are wound in the same manner around the winding windows 12d, Ild, and 13d, and the medium sliding surface is processed to have a desired curvature, thereby completing a head core as shown in FIG. 1.

The above example uses a metal-in-gap type head, but
As shown in FIGS. 4 and 5, a similar configuration can be implemented with a bulk head made of ferrite without a high permeability alloy magnetic film provided in the gap portion. This case differs from the above embodiment in that the manufacturing process of the alloy film is eliminated and the core halves are directly joined via the gap material.

This structure simplifies the manufacturing process because there is no process to form an alloy film using sendust alloy, etc., and at the same time reduces the stress on the ferrite material due to thermal stress in the adhesion process of each core and processing stress during cutting. This method has the advantage that magnetic heads can be manufactured at a high yield without causing cracks or the like.

[Effects of the Invention] As is clear from the above, according to the present invention, in a magnetic head in which a coil winding is applied to a winding window of a magnetic core obtained by butt-joining core halves, three magnetic The cores are laminated with a non-magnetic conductor in between, and a winding window is provided at approximately the same position on each of the core halves of one of the magnetic cores on both sides that sandwich the central magnetic core, and the central magnetic core is connected to the magnetic cores on both sides. The winding windows of the central magnetic core are cut out so that they are unrelated to the magnetic path of the coil, and the winding windows of the central magnetic core are cut out so that the winding windows of the magnetic cores on both sides are provided with the winding windows of the opposite side. It is installed in half, and the magnetic cores on both sides are cut out so that they are independent of the magnetic path of the coil provided in the winding window of the central magnetic core, so the magnetic path of the three magnetic cores is With the non-magnetic conductor and the notch in each magnetic core magnetically and electrically isolated, separate signals can be recorded and reproduced between the central magnetic core and the magnetic cores on both sides without crosstalk. A plurality of magnetic gaps can be arranged in the same Herad chip, and there are excellent effects such as providing a magnetic head suitable for applications where the space for a magnetic head is limited, such as recording and reproducing audio and video signals in still video.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a magnetic head adopting the present invention, Figure 2 is a front view of the medium sliding surface of the head in Figure 1, and Figure 3 (A).
~(C) is a side view of each magnetic core in Figures 1 and 82, and Figure 4.
5 and 5 show different embodiments, FIG. 4 is a perspective view of the magnetic head, FIG. 5 is a front view of the medium sliding surface, and FIGS. 6 and 7.
The figures are perspective views showing the structures of different conventional magnetic heads. 2...Adhesive material 4.6.8...Magnetic gap 9...Nonmagnetic conductor 11.12.13...Magnetic core 11a, llb, 12a, 12b, 13a, 13b・
= Core half lie, 12c, 13c...notch li
d, 12d, 13d...Window window

Claims (1)

[Claims] 1) A magnetic head in which a coil winding is applied to a winding window of a magnetic core obtained by butt-joining core halves, comprising: 3
Two magnetic cores are laminated with a non-magnetic conductor in between, and a winding window is provided at approximately the same position on each core half of one of the magnetic cores on both sides that sandwich the central magnetic core. The winding window of the magnetic core is cut out so that it has no relation to the magnetic path of the coil, and the winding window of the central magnetic core is cut out on the side opposite to the winding windows of the magnetic cores on both sides. 1. A magnetic head, characterized in that the magnetic cores on both sides are cut out so as to have no relation to the magnetic path of the coil provided in the winding window of the central magnetic core. 2) Recording and reproducing the first signal with respect to a predetermined track of the magnetic recording medium using the central magnetic core;
2. The magnetic head according to claim 1, wherein the magnetic cores on both sides record and reproduce the second signal on two tracks on both sides of the first signal track. 3) The magnetic head according to claim 1 or 2, wherein gaps between the three magnetic cores are arranged substantially on the same straight line.