JPS61120314A - Thin film magnetic head - Google Patents

Abstract

PURPOSE:To obtain a thin film magnetic head that can increase capacity of a cylinder and reduce crosstalk from an adjacent track without changing a feeding mechanism system and without increasing the number of heads by making two adjoining thin film head cores of different azimuth angle a pair, combining even number of them and specifying their pitch of arrangement. CONSTITUTION:In a thin film magnetic head used in a movable head type magnetic disk device, two adjoining thin film head cores 1 of different azimuth angle are made to a pair and even number 2n of them are combined. They are so set that the head cores 1 are arranged in the direction of track width on a recording medium and the pitch Cp of arrangement satisfies an expression (1) for track pitch Tp on the recording medium, and constituted to enable head cores 1 to record and reproduce independently. By shifting the magnetic head in the direction of track width to make the feeding pitch Hp keep relation of an expression (2), each head core 1 corresponds interleaving in the direction of track width and other head cores 1 are not positioned in the same track.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to an improvement in a thin film magnetic head used in a movable head type magnetic disk device.

(Prior Art VFi> Conventionally, in movable head type magnetic disk devices such as hard magnetic disks and flexible magnetic disks for computers, a large number of concentric information tracks are provided on the surface of one or more (a) recording media. One or more (b) floating magnetic heads for recording and reproducing information tracks are disposed on the surface of each medium, and arbitrary information is accessed by moving the magnetic heads in the radial direction.

Usually, a floating magnetic head is rigidly coupled in the floating direction to an actuator that moves in the radial direction via a soft support spring, and one floating magnetic head is connected to one recording/reproducing transducer (head core). In order to have 1
In one access, a number of tracks corresponding to the product of (a) and (b) above can be recorded and reproduced. This (a) X (b)
The storage capacity for a t-rack is called cylinder capacity, and is one of the important performance indicators of a magnetic disk device.

(Problem to be solved by the invention) In order to increase the cylinder capacity mentioned above, the number of media or one
Although it is possible to increase the number of floating magnetic heads disposed on the surface of the medium, both methods have the problem of increasing costs due to an increase in the number of component parts and complicating the assembly process. In addition, when the media surface is divided into several zones, it is necessary to adjust the positional relationship of the heads corresponding to each zone, and this is applied to contact start/stop (CPS) type magnetic disks. C8 in case
There is a problem in that the required medium area for the S method increases, and the area in which information can be effectively recorded decreases.

In addition, in order to obtain high track density in VTRs, etc., by recording and reproducing adjacent tracks using head cores with different azimuth angles, crosstalk from adjacent tracks can be reduced and high signal quality can be obtained. In a magnetic head, as a result of one head core recording and reproducing information on adjacent tracks, it was not possible to reduce crosstalk from adjacent tracks by recording and reproducing information on adjacent tracks with head cores having different azimuth angles. When attempting to arrange two floating magnetic heads with different azimuths in order to reduce crosstalk from adjacent tracks, the spacing between the two head cores must be set with greater accuracy than the track positioning accuracy, which is difficult to achieve. there were.

(Object of the Invention) In view of the above problems, the object of the present invention is to increase the cylinder capacity without changing the feed mechanism system or increasing the number of heads.
The present invention also aims to provide a thin film magnetic head that can reduce crosstalk from adjacent tracks.

, (Means for Solving the Problems) In order to achieve the above object, the present invention provides a thin 1t! i! In a magnetic head, an even number (2n) of two adjacent thin-film head cores with different azimuth angles are coupled in pairs, and each thin-film head core is arranged in the track width direction of the recording medium and at its arrangement pitch (CD ) is set to satisfy the following formula for the track pitch (Tp) on the recording medium, Cp=(2n+2m-1)T.

(However, n is a natural number and 2m is a non-negative integer.) Each thin film head core was configured to be able to record and reproduce independently.

(Function) According to the present invention, by moving the magnetic head in the track width direction at a predetermined feed pitch, the head cores are interleaved in the track width direction and correspond to each other, and no other head core is located on the same track. , multiple tracks of independent information can be simultaneously recorded and reproduced from one magnetic head in one access, and the cylinder capacity can be increased without increasing the number of heads per medium surface.

(Embodiment) FIG. 1 shows an embodiment of a floating thin film magnetic head (hereinafter referred to as a head) according to the present invention, in which 1 is a thin film head core (hereinafter referred to as a head core), 2 is a slider member, and 3 is a thin film head core (hereinafter referred to as a head core). is a part of a support spring that supports the head, 4 is a thin film head winding (hereinafter referred to as head winding), CW is the track width of the head core 1, and Cρ is the arrangement pitch of the head core 1.

The arrow indicates the direction of movement of the recording medium (not shown) relative to the head. Each of the head cores 1 has an even number (2n) 1111 (4 in this embodiment) of two adjacent head cores forming a pair.
They are provided on each vertical end surface of the slider member 2 with alternating inclination angles (azimuth angles) in the track width direction so as to be connected to each other. Therefore, two adjacent head cores 1
have different azimuth angles.

The track pitch Tp on the medium is usually constant and TD>
In the embodiment of the present invention in which CW is used and four head cores 1 are mounted on one magnetic head, Cp is Cp - (4,002 m-1) Tp (m-0, 1, 2, 3) with respect to the track pitch. ...), and each head core 1 is rigidly connected.

The magnetic head according to the present invention has a feed bit Hp of Hp=4T.
The movement I is made in the track width (radial direction in the case of a disk device) direction so as to maintain the relationship p. Figure 2 shows an example where m = 2, and the track arrangement on the medium is as shown in the figure.
The head cores 1 correspond to each other by being interleaved in the width direction, and no other identical head cores 1 are located in the same track T. Therefore, if a recording/reproducing amplifier 5 is provided corresponding to the head winding II 4 of each head core 1 as shown in FIG. 3, independent information for four tracks can be read simultaneously from one magnetic head in one access. Furthermore, as shown in FIG. 4, if connected to a single recording/reproducing amplifier 5 via a switching circuit 6, independent information for four tracks can be sequentially recorded and reproduced simply by selecting the head core 1. Cylinder capacity can be increased without increasing the number of heads per unit.

In addition, since the feed pitch is constant regardless of the track position, the feed mechanism is no different from conventional magnetic disk drives; the feed pitch only needs to be set to four times the track pitch, and all tracks can be scanned. The number of feeds required for this can be reduced to 1/4.

Furthermore, this magnetic head has two different azimuth angles (
Head core 1 with 1-θ and -θ)
(In FIG. 2, Δ, A' and B, B' have different azimuth angles) are paired and arranged in the above-mentioned relationship, so the tracks on the medium are arranged between head cores with different azimuth angles. The tracks correspond to each other alternately, making it possible to perform playback with reduced crosstalk from adjacent tracks, similar to a VTR.

In such a head, if the head core is formed using photolithography technology like a thin film magnetic head, Cp can be easily determined and obtained using a photomask.

That is, as shown in FIGS. 5(a) and 5(a''), a substrate or a protective film is deposited at a pitch Cp on a substrate 10 forming a normal thin film head or on a protective film 10' attached to the substrate. A mask 11 made of a material with a higher etching rate is attached. When this is etched, a fifth
11 plate shape as shown in figure (b), i.e. azimuth angle θ
A surface consisting of adjacent sloped surfaces with different values can be formed.

Even if etching is continued even after the mask is completely etched, the same material is etched and the surface shape does not change, so control is extremely simple.

Since it is usually sufficient for the azimuth angle θ to be several degrees or more, for example, an AI mask can be used to irradiate an Al2O3 protective film.
Such a surface can be obtained by sputter etching in a plasma. Even with chemical etching, such surface treatment is possible if the mask material and etchant are appropriately selected.

If a normal thin film magnetic head is formed on the surface obtained in the above process, a thin film rad wafer as shown in FIG. A floating thin film magnetic head as shown in the figure is obtained. Since the core pitch can be set as wide as 10 minutes, there are no restrictions when forming a thin film magnetic head, and thin film magnetic heads can be formed as before.

The above explanation was given for the embodiment of the present invention in which four head cores are mounted on one magnetic head, but in general, in the case of 2n head cores, Cp = (2n + 2m-1)Tp n; natural number 9m; non-negative By maintaining the relationship of integer t-1-2nxTp, a relationship is established in which the head core corresponding to one track is always the same and all tracks on the medium can be recorded and reproduced at a constant feed pitch.

In any case, since multiple tracks can be recorded and played back with one head, the cylinder capacity can be increased without increasing assembly man-hours or increasing the C8S area as would be the case when multiple heads are placed on the media surface. is possible, and there is no need for any ingenuity in the feeding mechanism system.

Although the above explanation uses a magnetic disk as an example, the present invention can of course also be applied to magnetic tape devices, such as devices that require high data transfer speeds such as narrow track pitch rotary head type digital VTRs, and PCM recording. It can also be used for machines etc.

(Effects of the Invention) As explained above, according to the present invention, in a thin film magnetic head used for mounting an angular head type magnetic disk,
An even number (2n) of two adjacent thin film head cores with a short azimuth angle are coupled in pairs, and the arrangement of each thin film head core is in the track width direction on the recording medium, and the arrangement pitch (Cp) is the same as the recording medium. Upper track pitch (Tp
) is set to satisfy the following formula, and Cp-(2n+2m-1)Tp (where n is a natural number and 1m is a non-negative integer). The cylinder capacity can be increased without changing the number of heads or increasing the number of heads, and has the advantage of reducing crosstalk from adjacent tracks.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of a thin film magnetic head according to the present invention, FIG. 2 is an explanatory diagram of the relationship between the head of the present invention and the track arrangement on a medium, and FIG. 3 is a recording/reproduction when using the head of the present invention. Connection diagram with the circuit, Fig. 4 is another connection diagram with the recording/reproducing circuit when the head of the present invention is used, Fig. 5 (a) (a'')
(b) and (c) are explanatory views of the method for manufacturing a thin film magnetic head according to the present invention, (a) is a perspective view when a mask is formed on the protective crotch, (a') is a partial cutaway view, (b) is a cross-sectional view after etching is completed, and (c) is a cross-sectional view of A11 on the substrate.
l! An example of a wafer after head formation is shown. DESCRIPTION OF SYMBOLS 1... Thin film head core, 2... Slider member, 3...
...Support spring, 4...Thin film head winding, 5...Recording/reproducing amplifier, 6...Switching circuit, 1o...Substrate, 10
'...Protective film, 11...Mask, CW: Track width of head core, TW track width, C
p: head core pitch, Tp Nidorak pitch, θ, θ
′: Azimuth angle

Claims (1)

[Claims] In a thin-film magnetic head used in a movable head type magnetic disk device, an even number (2n) of two adjacent thin-film head cores having different azimuth angles are coupled in pairs, and the arrangement of each thin-film head core is recorded. The arrangement pitch (Cp) is set in the track width direction on the medium so as to satisfy the following formula with respect to the track pitch (Tp) on the recording medium,
Cp=(2n+2m-1)Tp (where n is a natural number and m is a non-negative integer) A thin-film magnetic head characterized in that each thin-film head core is configured to independently perform recording and reproduction.