JPH01307905A - Magnetic head assembly - Google Patents

Abstract

PURPOSE:To suppress the floating of a tape, and also, to easily assemble a magnetic head assembly into a device by providing a recessed part for setting the upper part of a head gap to almost the atmospheric pressure, on a pad. CONSTITUTION:A running tape 21 is held by a magnetic head 22 and a pad 23. The magnetic head 22 and the pad 23 are formed to a roughly cylindrical shape, and in the pad 23, a roughly linear recessed part is provided in the wall thickness direction of the magnetic head 22, and its recessed part is worked up to a head gap 24 of the magnetic head 22, and also, length in the wall thickness direction of the magnetic head 22 of this recessed part is set longer than width of the tape 21. In this case, the inside of the recessed part provided on the pad becomes the atmospheric pressure, and on the head gap, as well, the atmospheric pressure is held by receiving its influence. In such a way, the floating of the tape 21 is suppressed, and also, a magnetic head assembly can be assembled easily into a magnetic tape device.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic head assembly for a signal input/output device using a magnetic tape, typified by a magnetic tape device for backing up computer data.

As a typical example of conventional technology, a data cartridge drive system, which is a magnetic tape device mainly for personal computers, will be described.

In a conventional magnetic head assembly, as shown in FIG. 2, a magnetic tape (hereinafter referred to as "1 tape") 1 has six
0 inch per second (Lnc+h persecon
d (hereinafter abbreviated as "IPS'"), the magnetic head 2 and a pad 3 fixed to the magnetic head 2 are configured to hold this. FIG. 2(a) is a schematic cross-sectional view of the magnetic head assembly. The magnetic head 2 usually consists of two magnetic heads fixed to each other via a magnetic insulating member 4, each of which performs recording and reproduction. The tape running side surfaces of the magnetic head 2 and pad 3 are cylindrical with the same diameter. In order to realize reliable recording and reproduction of signals via the tape 1, it is necessary that the head gap 5 of the magnetic head 2 be in stable contact with the tape 1. However, the magnetic head 2
Since the pad 3 has a cylindrical shape and the tape 1 runs at high speed, an air film is created between the magnetic head 2 and the tape 1.

The configuration was such that reliable recording and playback was impaired.

Here, if the flying height of the tape 1 from the magnetic head 2 is δ, and the radius of the magnetic head 2 and pad 3 is R, it has been found both experimentally and theoretically that δ is approximately proportional to R. There is.

Therefore, as an attempt to suppress such floating of the tape, a magnetic head assembly as shown in FIGS. 3(a) and 3(b) is often used. The cross-sectional shapes of a magnetic head 12 and a pad 13 that keep the tape 11 running are set to have a flat top and a straight slope, and the top and slope are smoothly connected by a small arc. By placing the head gap in that small R part,
This is to suppress floating of the tape 11 and to obtain stable contact.

Problems to be Solved by the Invention However, when attempting to assemble a magnetic head assembly into a magnetic tape device, if a small radius is set only in the head gap portion, the contact area between the magnetic head and the tape is extremely small, making assembly difficult. It was more susceptible to errors.

For example, in FIG. 3(b), when the magnetic head 12 rotates by a small angle with respect to the tape 11 in a plane parallel to the plane of the paper,
The tape 11 does not come into contact with the head gap, but comes into contact with a portion having an R portion near the head gap.

As described above, current data cartridge drive systems have encountered problems in that very high precision is required to suppress floating of the tape and to assemble and adjust the magnetic head assembly into the device.

In view of the above-mentioned drawbacks, the present invention provides a configuration that suppresses floating of the tape, ensures reliable contact between the head gap and the tape, and facilitates assembly of a magnetic head assembly into a magnetic tape device.

Means for Solving the Problems In order to solve the above-mentioned problems, a magnetic head assembly of the present invention includes a magnetic head, and a magnetic head assembly that is fixed to both sides of the magnetic head in the thickness direction, and that the magnetic head assembly is fixed to both sides of the magnetic head in the thickness direction, and that the magnetic head assembly is fixed to both sides of the magnetic head in the thickness direction. The head has a configuration including a pad having a substantially linear recess in the thickness direction of the head.

According to the present invention, with the above-described configuration, the inside of the recess formed in the pad extending to the vicinity of the head gap becomes almost atmospheric pressure, thereby alleviating the increase in pressure on the magnetic head and suppressing the floating of the tape.

Therefore, there is no need to reduce the radius of the head gap in order to suppress floating, and the magnetic head assembly can be easily assembled into the device.

EXAMPLES Hereinafter, examples of the present invention will be described with reference to the drawings. FIG. 1(a) is a perspective view showing a magnetic head assembly according to an embodiment of the present invention, and FIG. 1(a) is a cross-sectional view thereof.

In FIG. 1, 21 is a tape, 22 is a magnetic head, 2
Pads 3 are fixed to both sides of the magnetic head 22 in the thickness direction, and the magnetic head 22 and pads 23 hold the tape 21 running.

The magnetic head 22 and pad 23 have a substantially cylindrical shape, but the pad 23 has a substantially linear recess in the thickness direction of the magnetic head 22, and the recess is machined up to the head gap 24 of the magnetic head 22. has been done. Further, the length of the recessed portion in the thickness direction of the magnetic head 22 is set to be longer than the width of the tape 21.

The deformation behavior of the tape on the magnetic head assembly configured as above will be explained. If the thickness of the head 21 is ho and the width of the recess formed in the pad 23 is b, then b
is preferably set within the range of 20% to 200% of ho. Further, the depth of the recess may be at most 10 μm or more. At this time, the inside of the recess provided in the pad becomes atmospheric pressure, and the head gap is also influenced by this and is maintained at approximately atmospheric pressure. Therefore, almost no pressure increase occurs on the head gap due to tape running, and it becomes possible to reliably bring the head gap into contact with the tape as in the tape deformation shown in FIG. 1 (03).

The touch state between the tape and the head in the vicinity of the head was investigated by measuring the spacing between the head and the tape using optical interferometry. In other words, by running a transparent polyethylene terephthalate tape instead of a magnetic tape and applying illumination with uniform wavelengths to some extent, we can see bright and dark stripes due to light interference depending on the spacing between the head and the tape. . The results revealed that the head gap and tape were in stable contact. Furthermore, it has been found that stable contact between the head gap and the tape is not impaired even when the head is slightly rotated and assembled in a plane parallel to the plane of the paper in FIG. 1 Φ).

Effects of the Invention As described above, the present invention suppresses floating of the tape by providing a concave portion on the pad to maintain almost atmospheric pressure above the head gap, and also makes it easy to assemble the magnetic head assembly into the device. It is possible to obtain stable input/output characteristics.

[Brief explanation of the drawing]

FIG. 1(a) is a perspective view of a magnetic head assembly according to an embodiment of the present invention, FIG. 1(b) is a schematic cross-sectional view of the magnetic head assembly, and FIG. 2(a) is a diagram of a conventional magnetic head assembly. FIG. 3(b) is a perspective view of another conventional magnetic head assembly, and FIG. 3(b) is a schematic view of the cross-section thereof. 21...Tape, 22...Magnetic head, 2
3...Pad, 24...Head gap. Name of agent: Patent attorney Toshio Nakao and 1 other person21
--Tape No. 15A23-''-Pad Figure 2

Claims (1)

[Claims] A magnetic head assembly comprising: a magnetic head; and pads that are fixed to both sides of the magnetic head in the thickness direction and have substantially linear recesses in the thickness direction of the magnetic head up to the vicinity of the head gap of the magnetic head.