JPH01100717A - Magnetic head - Google Patents

Abstract

PURPOSE:To enable two tracks to be recorded and reproduced and to shorten an average access time by providing two recording and reproducing gaps on one magnetic head, and separating them by a distance larger than recording track width with each other in the radius direction of a magnetic disk. CONSTITUTION:A first gap 4A is formed on a core block 5A on one side, and a second gap 4B on a core block 5B on the other side, and a magnetic core block 2 is constituted by jointing the end faces of those core blocks 5A and 5B with each other via a non-magnetic intermediate member 6. Thereby, the first gap 4A is separated from the second gap 4B by a prescribed distance L from each other in the rotating direction of the magnetic disk. Furthermore, the first gap 4A is separated from the second gap 4B by the distance larger than the recording track width in the radius direction of the magnetic disk. In such a way, the recording or the reproduction of the two tracks per one step of a stepping motor can be performed, and also, the average access time can be shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a magnetic head used in a magnetic recording device.
In particular, the present invention relates to a recording/reproducing magnetic head used in a floppy disk device or a hard disk device.

Conventional Technology In recent years, along with the miniaturization and increase in capacity of electronic computers, floppy disk devices have become one of the auxiliary storage devices! (below,
FDD) and hard disk drives (hereinafter referred to as HDD) are also required to be smaller, have larger capacity, and have faster access.

By the way, as a means of increasing the capacity of FDD and HDD,
Examples include increasing track density and increasing linear recording density. However, in the case of conventional FDDs and HDDs, one magnetic head has only one recording/reproducing gap.

It was necessary to access the magnetic head for recording and reproducing each track. This has the disadvantage that as the capacity of FDDs and HDDs increases, the total track access time inevitably becomes longer.

A conventional example will be described below with reference to the drawings.

Figure 1O shows the appearance of a conventional magnetic head.
51 is a magnetic core block for recording, reproducing, and erasing; FIG. 11 is an exploded perspective view of the magnetic core block 51, and FIG. 12 is a plan view of the magnetic core block 51. The magnetic core block 51 has a recording/reproducing (hereinafter referred to as R/W-) gap 52 and erasing (hereinafter referred to as E) gaps 53A and 53B, and a coil 55 for a layer coil 54 for R/W, respectively. has.

The E gaps 53A and 53B are necessary in order to completely erase the old recorded information even if the magnetic head goes off track when overwriting a predetermined track on the magnetic disk due to the R/W gap. Yes, but of course it is not necessary if there is very little off-track.

In the conventional magnetic head constructed as described above, arbitrary recording tracks of a magnetic disk are accessed randomly by a stepping motor, and other tracks must be accessed each time one track is recorded or reproduced.

Problems to be Solved by the Invention By the way, the access time of an FDD is determined by the following factors: ■ Head movement time between tracks, ■ Stabilization time after head movement, ■ Disk rotation waiting time, and ■ Time required for the head to completely contact the disk surface. It is determined by four factors: head load time. For this reason, the above-mentioned configuration in which access is made for each track has the problem that as the recording capacity increases, the average access time also increases as the number of tracks increases.

Therefore, an object of the present invention is to provide a magnetic head that can solve the above problems.

Means for Solving the Problems In order to solve the above problems, the magnetic head of the present invention has six
This is a ring-shaped magnetic head for a B-air disk, and has first and second gaps for recording and reproducing.

The first gap and the second gap are spaced apart from each other by a distance equal to or longer than the recording track width in the radial direction of the magnetic disk, and are also spaced apart from each other by a predetermined distance in the rotational direction of the magnetic disk.

Effects According to the above structure, one magnetic head is provided with two recording/reproducing gaps, and these gaps are separated from each other in the radial direction of the magnetic disk by a distance equal to or longer than the recording track width. During access, recording (or playback) can be performed using the first gap, and then recording (or playback) can be performed using the second gap. Therefore, recording and playback of two tracks is possible, and the average access time can be significantly shortened. can.

EMBODIMENT A magnetic head according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of a magnetic head according to a first embodiment of the present invention, FIG. 2 is a perspective view of its magnetic core block, and FIG.
The figure shows a plan view of a magnetic core block 6 In Figures 1 to 3, 1 is a magnetic head, the magnetic head is a magnetic core block 2, and this magnetic core block 2
It consists of traveling guides 3A and 3B attached to both sides of the vehicle. As shown in FIGS. 2 and 3, this magnetic core block 2 is made up of two ring-shaped core blocks 5A and 5B having gaps 4A and 4B, respectively, put together. That is, the first gap 4A is formed in one core block 5A, and the first gap 4A is formed in the other core block 5B.
A second gap 4B is formed in the magnetic core block 2, and the end faces of both core blocks 5A and 5B are joined via a non-magnetic intermediate member (for example, barium titanate) 6 to form the magnetic core block 2. Therefore, the first gap 4A and the second gap 4B are spaced apart from each other by a predetermined distance in the magnetic disk rotation direction. Furthermore, the first gap 4A and the second gap 4B are separated by a distance TP that is greater than the recording track width in the radial direction of the magnetic disk. That is, as shown in FIG. 3, after forming grooves 7A, 7B on both sides of each gap 4A, 4B of each core block 5A, 5B, each groove 7A, 7
B is filled with mold glass (non-magnetic material) 8, and each gap 4A.

The length of 4B (track width) is made dimensionally accurate. Note that the length (trap width) Wa of the first gap 4A and the length (track width) Wb of the second gap 4B are 33 μm.
The magnetic disks have the same dimensions, and the distance apart in the radial direction of the magnetic disks is 36 μm, which corresponds to the track pitch when the track density is 700 TPI (tracks/inch). Of course, these dimensions are appropriately determined depending on the track density.

Further, in FIGS. 1 and 2, 9A and 9B are read/write coils wound around the respective core blocks 5A and 5B by an intermediate member 6 interposed in the center.

Separate closed magnetic paths are formed in each core block 5A, 5B. Further, in FIG. 2, 10 is an adhesive glass.

In this embodiment, in order to minimize the off-track portion of the magnetic head, track positioning of the magnetic head is performed using track servo technology in which a servo pattern is written in the recording track in advance. Such an E gap is unnecessary.

Furthermore, in the FDD equipped with the magnetic head 1 of this embodiment,
The stepping motor is set to feed 72 μm per step. In other words, two tracks are recorded and reproduced for each step. In other words, recording (or playback) begins with the first
Recording (or reproduction) is performed using the gap 4A, and after one track round, the magnetic head 1 is held at that position and immediately switched to the second gap 4B to perform recording (or reproduction). Therefore, as a matter of course, the rotational waiting time, settling time, and inter-track access time of the magnetic disk are halved. In the example, the signal switching time from the first gap 4A to the second gap 4B is 30μ.
Sec was needed, so I made the second one to satisfy it.
The gap 4B is arranged at a distance of 500 μm (corresponding to L in FIG. 3) rearward in the rotational direction from the first gap 4A.

FIG. 4 shows the arrangement of the magnetic head 1 and the recording track 12 of the magnetic disk 11.

FIG. 5 shows a plan view of a magnetic core block in a second embodiment of the present invention. In this embodiment, instead of omitting the non-magnetic intermediate member 6 in the first embodiment and magnetically separating both closed magnetic circuits, both core blocks 5A,
5B, an intermediate core block 21 is arranged between them to share a magnetic path.

Furthermore, the groove processing on the common magnetic path side is also omitted, thereby significantly reducing the manufacturing cost of the magnetic head.

In the case of this magnetic head, compared to the first embodiment, since magnetic interference occurs between the first gap 4A and the second gap 4B, the track density is limited to about 600 TPI, but the manufacturing cost is low. It is advantageous in that it is inexpensive.

FIG. 6 shows a plan view of a magnetic core block in a third embodiment of the present invention. In this embodiment, the non-magnetic intermediate member (barium titanate) 6 in the first embodiment is omitted, It is attached using epoxy resin. Since the adhesive layer 22 has a thickness of about 1 to 3 μm, the magnetic interference between both closed magnetic circuits is extremely small as in the first embodiment, and the characteristics are exactly the same as in the first embodiment. there were.

FIG. 7 shows an exploded perspective view of a magnetic core block in a fourth embodiment of the present invention.

FIG. 8 shows a plan view of the magnetic core block.

This embodiment differs from the first embodiment in that the gap 31A,
Along a plane perpendicular to 31B, two divided core blocks 32A and 32B are placed between them with a non-magnetic intermediate member (
For example, it has a laminate structure with Western foil 33 interposed therebetween. The distance between the gaps 31A and 31B is adjusted depending on the thickness of the non-magnetic intermediate member 33. Functionally, it was exactly the same as the first embodiment. However, as the track density increases and the track width becomes narrower, it is necessary to make the core block thinner, and the track density of about 400 TPI is the limit in terms of processing technology. In addition, in Figure 7, 34
is composed of a non-magnetic material (eg barium titanate).

Further, in this embodiment, Western foil was used for the non-magnetic intermediate member 33, but this was omitted and the core block 32A was used.

A nonmagnetic layer may be formed by forming a thin film of a nonmagnetic material such as S i O on the side surface of 32B by sputtering.

FIG. 9 shows a plan view of a magnetic core block in a fifth embodiment of the present invention. In this embodiment, the core blocks 32A and 32B are made thicker in order to compensate for the disadvantage in processing technology that the core blocks cannot be made thinner when the track density is high in the fourth embodiment. To,
While forming grooves 35A and 35B, these grooves 35
A and 35B are filled with molded glass 36 to form a laminate type structure. In this example, a 700 PTI magnetic head could be constructed in the same manner as in the first example, and almost the same magnetic properties could be obtained.

Effects of the Invention According to the above configuration of the present invention, one magnetic head has two recording/reproducing gaps, and these gaps are spaced from each other by a distance equal to or longer than the recording track width in the radial direction of the magnetic disk. Therefore, it is possible to record or reproduce two tracks per step of the stepping motor, and the average access time can be significantly shortened.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a magnetic head in a first embodiment of the present invention, FIG. 2 is a perspective view of the magnetic core block in FIG. 1, FIG. 3 is a plan view of the magnetic core block, and FIG. 4 is a perspective view of the magnetic core block in FIG. A schematic diagram showing the arrangement of the magnetic head and the recording track of the magnetic disk in the first embodiment, FIGS. 5 and 6 are plan views of the magnetic core block in the second and third embodiments of the present invention, respectively, FIG. 7 is an exploded perspective view of the magnetic core block in the fourth embodiment, and FIGS. 8 and 9 are
10 is an external view of a conventional magnetic head, FIG. 11 is an exploded perspective view of the magnetic core block in FIG. 10, and FIG. The figure is a plan view of the same magnetic core block. 1...Magnetic head, 2...Magnetic core block, 4A
. 4B... 1st. 2nd gap, 5A, 5B... Core block, 6... Intermediate member, 7A, 7B... Groove portion, 8... Molded glass. 1st Figure 1 - Senji head 2 -,! Injection core 10 tsufu 4.4.4B-Ichiro q, 28' figure 2 figure 4 figure S figure 4/ / 4I3 figure 7 32B, t2A figure β figure 2 figure 1 rh

Claims (1)

[Claims] 1. A ring-shaped magnetic head for a magnetic disk, which has first and second gaps for recording and reproduction, and these first gaps and second gaps mutually record information in the radial direction of the magnetic disk. Magnetic heads are spaced apart by a distance equal to or longer than the track width and are also spaced apart from each other by a predetermined distance in the rotational direction of the magnetic disk. 2. The magnetic head according to claim 1, wherein the lengths of the first and second gaps along the radial direction of the magnetic disk are regulated by grooves filled with a non-magnetic material.