JPH06301926A - Thin film multi-channel magnetic head - Google Patents

Abstract

PURPOSE:To realize good mounting efficiency with stable tape touch and small irregularity in performance by making the winding number of coils on the outside of a magnetic gap larger than that on the side between two magnetic gaps of two thin film magnetic head elements. CONSTITUTION:In the magnetic head, one track is arranged in the widthwise direction and two tracks are arranged in a line in the running direction to have azimuth angles alternately changed. Coil conductors 8a, 8b are wound at the outside of a gap 5 of two tracks. Supposing that the winding number of coils on the side between the magnetic gaps of two head elements is N1, N2 and, the winding number of coils on the outside of each magnetic gap is N1', N2', 0<=N1<N1' and 0<=N2<N2' are held. By winding the coil conductors in this manner, the interval of gaps is made sufficiently narrow, so that the stable tape touch is easily realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film magnetic head used in a magnetic recording / reproducing apparatus such as a VTR, and more particularly to a thin film multi-channel head having a plurality of magnetic heads formed on the same substrate.

[0002]

2. Description of the Related Art VTRs are required to have high image quality and long-time recording for home and business use, and have been designed for wider bandwidth. Further, the next-generation VTR equipment requires further wideband transmission, but due to digitization, a multichannel recording system in which the wideband signal is divided into a plurality of magnetic heads and distributed and recorded is generally used. For this purpose, a multi-channel magnetic head is required, and because of the need for high-density recording, the track width is 10 μm or less, the accuracy is about 1 μm, and the positioning accuracy of each channel is naturally about 1 μm. Required. From these things, the thin film magnetic head is considered as one direction of the multi-channel magnetic head.

As an example thereof, there is a horizontal thin film multi-head described in Japanese Patent Laid-Open No. 4-11314. This thin-film magnetic head has a lower magnetic core, a conductor coil and an upper magnetic core, and the upper magnetic core is formed of a pair of magnetic core halves butted against each other via a magnetic gap. Is a face. According to this conventional example, not only the upper magnetic core having the track width can be formed with high accuracy, but also the track pitch and the azimuth angle when multi-channelized can be arbitrarily formed with high accuracy.

[0004]

However, in the horizontal type thin film multi-channel magnetic head according to the above-mentioned prior art, the coil forming surface and the zero gap depth surface of all tracks are on the same plane, which is as follows. Cause problems. No consideration is given to the fact that in order to obtain a stable tape touch, it is preferable that the tip of the head (both in the running direction and the track direction) has an R shape with an appropriate radius of curvature. Further, when the tip has an R shape, the gap depths of the tracks when three or more are arranged in the traveling direction are different, which causes a problem of large performance variation.

This will be described with reference to the drawings. FIG. 5 shows a conceptual diagram of a horizontal thin-film multi-head in which the tip of the head has an R shape. In the figure, 1 is the substrate, 11 is the substrate surface,
Reference numeral 2 is a plane connecting the surfaces of the thin film coil, 3 is a plane connecting zero gap depth, 4 is a sliding surface having an appropriate R shape for contacting the tape, and 5 is a magnetic gap (the magnetic core is omitted). . This conceptual diagram shows a multi-track configuration of 3 channels in the track width direction and 6 channels in the traveling direction. The initial rounded shape of the head tip has a radius of curvature Rx and Ry of 1 m in the running direction and the track width direction, respectively.
m, about 10 mm.

The plane 2 connecting the coil surfaces and the plane 3 connecting the zero gap depths shown in FIG. 5 are parallel to the substrate surface 11. That is, the planes 2 and 3 have different distances to the sliding surface 4 depending on the place, and in a large case, if the area is increased, the planes 2 and 3 intersect the sliding surface 4. Become.

Therefore, the area where the coil can be formed is limited by the width in the track width direction (generally the chip width), and the number of tracks that can be arranged in the track width direction is limited.
Also, since the distance between the plane 3 connecting the zero gap depth and the sliding surface 4 differs depending on the location, when the number of tracks arranged in the running direction and the track width direction exceeds two channels, the gap depth of each head is However, there is a problem that the performance varies depending on the location.

A more specific description will be given with reference to the drawings. The calculation result of the difference in the gap depth is shown in FIG. FIG. 6 shows the difference in gap depth between the inner two tracks and the outer two tracks when the four gaps are arranged by making the gap intervals uniform in the traveling direction, Rx and the gap interval l.
Is shown as a parameter.

Here, when the output variation specification of each track is within 1 dB, the output gap depth dependency is about 0.2 to 0.3 dB / μm, so that the gap depth of four heads is The difference needs to be about 4 μm or less. Therefore, from this figure, the gap interval l is about 150
The number of tracks that can be arranged in the traveling direction is limited to four, considering the required number of coil turns and the coil forming space for that, because the number of tracks must be set to about μm or less. When three trucks are arranged in the traveling direction, it is the same as when four trucks are arranged. When only two tracks are arranged in the running direction, the problem of gap depth difference does not occur as described above, and the gap interval may be set appropriately from the viewpoint of ensuring a stable tape touch.

As described above, in the horizontal type thin-film multi-channel magnetic head, if the sliding surface is provided with an appropriate R in order to obtain good mounting performance, there is a problem that the performance variation of each track becomes large in the prior art. is there. For both the problems of tape touch stabilization and gap depth of each track, the direction of improvement is to make the gap interval as narrow as possible, but there is also a tradeoff with the number of coil windings required to secure output, so conventional head elements The structure was not enough.

An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a horizontal thin-film multi-channel magnetic head which realizes good mounting performance with stable tape touch and small performance variation width. It is to be.

[0012]

The above-mentioned objects are as follows. First, in the case of arranging two tracks in the traveling direction, 1) the number of coil turns wound on the side sandwiched between two magnetic gaps of two thin film magnetic head elements. Is less than the number of coil turns wound outside the gap.

Or, 2) The gap position of each head element is formed closer to the center of the two head elements than the center of each lower core.

This is achieved by Furthermore, 3) The two-track element formed by minimizing the gap interval in this way is considered as one magnetic head, and
One chip is separated by a predetermined distance in the traveling direction, and a maximum of 4 tracks are arranged in the traveling direction.

It is achieved by:

[0016]

With the above-described coil winding method or the structure in which the gap position is shifted from the center of the lower core to the center of the head chip, the gap distance of two tracks can be reduced from that of the conventional case when the number of coil windings is constant. It can be halved. In addition, when two 2-track heads having a gap interval that is half that of the prior art are arranged in one chip to form a 4-track structure, the difference in gap depth between the inner two tracks and the outer two tracks is It can be about half the size of the conventional one.

[0017]

EXAMPLES The present invention will be described in detail below with reference to examples. FIG. 1 is a diagram showing a first embodiment in which two tracks are mounted on one chip according to the present invention. (A) is a perspective view of the entire head chip, (b) is a front view of a sliding surface, and FIG. FIG. 3 is a cross-sectional view of one head element in the traveling direction. In the figure, 1 is a substrate, and 11 is a surface of the substrate 1, which is a head element formation surface. 4 is the curvature Rx in the traveling direction and the curvature R in the track width direction
On the sliding surface of the magnetic tape having y, two upper magnetic core halves 6 abutting each other with a magnetic gap 5 in between are exposed. The magnetic gap 5 has an upper magnetic core 6 exposed on the sliding surface 4 to reduce the contour effect.
Is formed non-parallel to the end of the. Further, 61 is a lower magnetic core, 7 is a protective film formed on the head elements in order to protect each head element and obtain a good tape touch, 71 is an insulating film of the coil conductors 8a and 8b, and 8 is a substrate. 3 shows a schematic forming space of the formed thin film coils 8a and 8b, 9 is an electrode terminal drawn out from the coil to a side surface on the back surface side of the substrate through a through hole 9'opened in the substrate, 2 is a coil surface The plane 3 connecting the two is a plane connecting the zero gap depth.

In the present embodiment, one track in the track width direction and two tracks in the running direction are arranged side by side so that the azimuth angle alternates, as shown in FIGS. 1 (b) and 2. In addition, the coil conductors 8a and 8b are wound around the two-track gap outside. By adopting such a winding method of the coil conductor, the gap interval 1 can be sufficiently narrowed and a stable tape touch can be easily realized. For example, if the magnetic path length is 200 μm and the space in the magnetic path is designed to be used for coil formation to the maximum extent, the gap is about 250 μm in the conventional case (when the coil conductors are evenly wound inside and outside the gap of two tracks). However, according to the present invention, the two gaps can be arranged close to each other by about half.

As described above, according to the present invention, the gap distance 1 can be reduced to about half that of the conventional structure, and a good tape touch in the mounted state can be easily realized.

Next, another embodiment in which the gap interval can be shortened in a two-track thin film multi-head is shown in FIG.
Shown in. (A), (b), (c) is a front view of a sliding surface corresponding to FIG. 1 (b) showing the second, third, and fourth embodiments. The second embodiment is an example in which the position of the magnetic gap 5 is further shifted from the center of the lower core 61 to the inside of the gap between the two tracks in the first embodiment, and the gap distance l is 100 μm or less. It is also possible to

The third embodiment is an example in which the gap distance l is reduced by making the number of coil turns inside the gap of two tracks smaller than the number of turns outside the gap. The third embodiment is an example in which the position 5 of the magnetic gap is formed in the conventional coil structure so as to be displaced from the center of the lower core 61 to the inside of the gap between two tracks.

Next, a fifth embodiment having a 4-track structure will be described with reference to FIG. In the present embodiment, one set in which the gap distance l between the two tracks is reduced in the first embodiment is arranged two sets apart by a predetermined distance L (L> l) in the traveling direction,
It has a structure in which four tracks are integrated. The same parts as those in FIG. 1 are designated by the same reference numerals. In this example, the gap distance l in the first embodiment determines the gap depth difference of 4 tracks. Although the effect when compared with the conventional structure varies depending on the magnetic path length, the number of coil turns, and the like, for example, in the above-described structure, the gap distance 1 can be set to about 100 μm in FIG. The difference in the gap depth between the inner two tracks and the outer two tracks is about 2 to 3 μm, which is about half that in the case where the conventional gap positions are evenly arranged.

Although the fifth embodiment is a combination with the first embodiment, it goes without saying that a combination with the second to fourth embodiments is also possible. As described above, according to the present embodiment, in the multi-head having four tracks arranged in the traveling direction, the gap depth between the tracks can be made smaller than in the conventional case, the performance variation is small, and stable mounting performance can be easily obtained. Came to be.

[0024]

As is apparent from the detailed description of the embodiments, according to the present invention, the tape touch is stable,
It has become possible to create a horizontal thin-film multi-channel magnetic head that achieves good mounting performance with small performance variations.

[Brief description of drawings]

FIG. 1A is a perspective view of a whole head chip and FIG. 1B is a front view of a sliding surface of a thin film multi-channel magnetic head according to the present invention.

FIG. 2 is a sectional view of two head elements in the traveling direction.

FIG. 3 is a front view of a sliding surface showing second, third and fourth embodiments of the thin film multi-channel magnetic head according to the present invention.

FIG. 4A is a perspective view of an entire head chip and FIG. 4B is a front view of a sliding surface of a thin film multi-channel magnetic head according to a fifth embodiment of the present invention.

FIG. 5 is a perspective view of a horizontal thin-film multi-channel magnetic head having an R shape at the head end for explaining the conventional technique.

FIG. 6 is a diagram showing a relationship between a gap depth difference and Rx and a gap interval when four tracks are arranged in the traveling direction.

[Explanation of symbols]

1 ... Substrate, 2 ... Plane connecting thin film coil surfaces, 3 ... Plane connecting zero gap depth, 4 ... Sliding surface, 5 ... Magnetic gap, 6, 6a, 6b ... Upper magnetic core, 61 ... Lower magnetic core, 7, 7a, 7b ... Protective film made of non-magnetic insulating film, 7
1 ... Coil insulating film, 8 ... Coil forming region, 8a, 8b ...
Coil conductor, 9 ... Coil terminal, 10 ... Head base, 1
1 ... Substrate surface, 12 ... Reference plane common to each track, 13 ...
Marker, 14 ... Chip separation line, 91 ... Electrode terminal on head base.

Front page continuation (72) Inventor Yuko Shibayama 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Ltd.

Claims (3)

[Claims] 1. A lower magnetic core (61), thin film coil conductors (8a), (8b), and a coil insulating layer (7) on a substrate (1).
1), an upper magnetic core (6), a protective film (7) and the like are sequentially laminated, and the upper core (6) includes a pair of upper magnetic core halves (6a) and (6b) and a lower magnetic core (6b). 1) a thin film magnetic head element which is formed by abutting a magnetic gap (5) substantially perpendicular to the surface of (61) and whose surface of the upper core (6) is a sliding surface (4) with a recording medium. In a thin film multi-channel magnetic head formed on a chip, two thin film magnetic heads are arranged in the running direction,
In addition, the number of coil turns of the two magnetic head elements wound on the side sandwiched by the magnetic gaps of the two head elements is N
_{When 1} and N ₂ and the number of coil turns of two magnetic heads wound outside the two magnetic gaps are N ₁ ′ and N ₂ ′, 0 ≦ N ₁ <N ₁ ′, 0 ≦ N ₂ A thin film multi-channel magnetic head characterized by the relationship <N ₂ '. 2. A lower magnetic core (61), thin-film coil conductors (8a), (8b) and a coil insulating layer (7) on a substrate (1).
1), an upper magnetic core (6), a protective film (7) and the like are sequentially laminated, and the upper core (6) includes a pair of upper magnetic core halves (6a) and (6b) and a lower magnetic core (6b). 1) a thin film magnetic head element which is formed by abutting a magnetic gap (5) substantially perpendicular to the surface of (61) and whose surface of the upper core (6) is a sliding surface (4) with a recording medium. In a thin film multi-channel magnetic head formed on a chip, two thin film magnetic heads are arranged in the running direction,
A thin film multi-channel magnetic head, wherein each of the magnetic gaps of the two magnetic head elements is provided so as to be offset from the center of the two magnetic head elements. 3. A gap distance between two thin film multi-channel magnetic heads, which are the innermost sides of two thin film multi-channel magnetic heads, wherein the gap distance between the two thin film magnetic head elements is 1. A thin film multi-channel magnetic head characterized in that it is arranged in the running direction such that L is larger than 1.