JPH04221402A - Magnetic recording/reproducing apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a magnetic recording and reproducing apparatus using a magnetic head having a structure in which a second substrate is bonded to the surface of a magnetic layer formed on a first substrate through a glass material. Regarding.

0002

[Background Art] In recent years, magnetic recording and reproducing devices have been trending toward smaller size and higher density. Metal heads are becoming mainstream.

[0003] An example of a metal head is a laminated head, which has a structure in which a magnetic metal layer forming a magnetic path is laminated on a non-magnetic substrate, and is sandwiched between another non-magnetic substrate with a glass material in between. and MIG (Me
tal in gap) heads, etc., and have been put to practical use mainly in the field of video tape recorders (hereinafter referred to as VTRs). In particular, compared to ferrite heads and MIG heads, the former laminated head can easily produce heads with narrow track widths necessary for high density using sputtering methods, etc., and forms a magnetic path without any sliding noise due to ferrite parts. By forming the magnetic layer with a multilayer structure with an insulating layer interposed therebetween, it has the advantage that eddy current loss can be reduced.

0004

[Problems to be Solved by the Invention] On the other hand, the disadvantages of the laminated head include low recording efficiency due to the small cross-sectional area of the magnetic path, and difficulty in achieving compatibility in terms of sliding characteristics with various magnetic recording media. However, the compatibility with various media regarding the sliding characteristics related to the present invention will be explained below using FIG. 2, which is a cross-sectional view in the layer thickness direction. In the case of a laminated metal head, the sliding surface that comes into contact with the magnetic recording medium during recording and reproduction is composed of nonmagnetic substrates 1 and 2, a magnetic layer 3, and a glass material 4. Because the wear characteristics of the parts are different from each other, a step as shown in Fig. 2 occurs between the magnetic layer part, the glass material part, and the substrate surface (hereinafter referred to as
(referred to as uneven wear). The level difference due to such uneven wear causes spacing loss during recording and reproduction, and deteriorates the magnetic recording and reproduction characteristics. The uneven head wear described above is caused by the non-magnetic substrates 1 and 2 for certain magnetic recording media.
By combining this with the material constituting the magnetic layer 3, it can be reduced to a level that poses no practical problem. However, even a laminated head that does not easily cause uneven wear on certain types of media is often prone to uneven wear when sliding other types of magnetic recording media. For example, in the case of a VTR, MP (M
etal Powder (metal powder coated type) Non-magnetic substrates 1 and 2 and magnetic layer 3 according to coated media such as tape.
When recording and reproducing a metal thin film type medium using a head made of a combination of materials forming the head, it may happen that good recording and reproducing characteristics cannot be obtained due to uneven wear of the head. In addition to conventional magnetic recording tapes using metal oxides, MP tapes,
ME (Metal Evaporated)
Many types of media such as tape are in practical useV
In the field of TR, compatibility with various media is particularly important, and there is an urgent need for improvements in this respect in stacked heads.

[0005] Uneven wear of the laminated head is thought to occur in the following manner in many cases. It is the glass material 4 that is most likely to wear due to sliding with the medium, and first a step is created between the glass material portion and the substrate surface. This difference in level creates a gap between the magnetic layer 3 and the second substrate 2 as shown in FIG. 2, and floating coating particles that collect in this gap accelerate wear of the magnetic layer 3. The magnetic layer 3 gradually wears away from the side in contact with the glass material 4, creating a step between it and the substrate surface. As can be easily inferred from the above, the difference in level between the magnetic layer 3 and the substrate surface is larger on the second substrate 2 side than on the first substrate 1.
Small on the side. This situation can be observed using a surface roughness meter or the like as shown by the curve AB shown in FIG. From the above,
It is considered that if the wear of the glass material 4 is reduced, the wear of the magnetic layer 3 is also reduced.

An object of the present invention is to provide a magnetic recording/reproducing apparatus that solves the above-mentioned conventional problems.

[0007]

[Means for Solving the Problems] In order to achieve the above object, a magnetic recording/reproducing device of the present invention has a second substrate bonded to the surface of a magnetic layer formed on a first substrate via a glass material. Relative running speed of magnetic recording medium to magnetic head with laminated structure

[0008]

[Outside 2]

[0009] The layer thickness direction of the magnetic layer is directed from the second substrate toward the first substrate.

0010

[Math 2]

[0011] The structure is such that it has a velocity component of the above magnitude.

0012

[Operation] With the above-described structure, the present invention can sufficiently reduce uneven wear of the head even if the type and material of the magnetic recording medium changes.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

[0014] In investigating the uneven wear of the laminated head, we investigated the relative running speed of the magnetic recording medium with respect to the head, as shown in Figure 1.

[0015]

[Outer 3]

6, the layer thickness direction of the magnetic layer 3 is placed on the second substrate 2.
It has been found that by having a velocity component of a certain value or more in the direction from the first substrate 1 to the first substrate 1, the wear of the glass material 4 is reduced, and therefore the wear of the magnetic layer 3 is also reduced. This also reduces differences in head wear characteristics depending on the type of media, and as a result, it is possible to improve compatibility with various media regarding sliding characteristics.

This is because the head enters the medium from the second substrate 2 side, which is less likely to be worn out than the magnetic layer 3 and the glass material 4, so that the medium that is applied to the surface of the glass material 4 immediately after that enters the medium. It is assumed that the pressure from the surface is reduced, but the detailed mechanism is unknown. In the case of a conventional magnetic recording/reproducing device, the relative traveling speed of the medium with respect to the head is in the in-plane direction of the magnetic layer, and the above effects cannot be obtained. Also, the relative running speed of the magnetic recording medium to the head

[0018]

[Outside 4]

6 has a velocity component in the direction from the first substrate 1 to the second substrate 2 in the layer thickness direction of the magnetic layer 3, contrary to FIG. However, after that, the glass material 4 enters the medium through the magnetic layer 3, which is relatively easily worn, and the above-mentioned effect cannot be obtained.

The configuration of the present invention, as shown in FIG. 1, for example, uses a head in which the first substrate 1 and the second substrate 2 are not parallel flat plates but are cut diagonally, thereby making it possible to avoid the conventional V.
This can be easily achieved with a TR deck, etc. Below, an example will be shown in which the above-described reduction in uneven wear of the head and improvement in compatibility with various media have been confirmed using the head and VTR deck shown in FIG. 1.

A head having the structure shown in FIG. 1 was mounted on a cylinder of a VTR deck, and its wear characteristics with respect to various magnetic recording tapes were investigated. At this time, the relative traveling speed of the medium to the head

[0022]

[Outer 5]

The angle θ that 6 forms with the in-plane direction component 8 of the magnetic layer was varied. The setting of θ is based on the first substrate 1 and the second substrate 1.
This was done by changing the angle when cutting the substrate 2 diagonally. At this time, the relative traveling speed of the medium to the head

[
0024

[Outside 6]

The magnitudes of the magnetic layer in-plane direction component 8 and magnetic layer thickness direction component 7 of 6 are respectively

[0026]

[Math 3]

[0027] Here, if θ is a positive value, then

0
028]

[Outside 7]

The direction component 7 in the magnetic layer thickness direction is directed from the second substrate 2 to the first substrate 1, and when θ is a negative value, the direction is directed from the first substrate 1 to the second substrate 2. shall be. The amount of uneven wear of the head was evaluated using the distance d between the center line MM' of the surface cross-sectional curve AB of the magnetic layer near the head gap and the substrate surface, as shown in FIG. Note that the surface cross-sectional curve AB was measured using a scanning tunneling microscope (STM).

As an example of reducing the amount of uneven head wear according to the present invention, Ti, C and Ti are used as the first substrate 1 and the second substrate 2.
Figure 3 shows the θ dependence of the head uneven wear amount d when a Co-Cr perpendicular magnetic recording tape is slid by a Co-based amorphous laminated head using a ceramic substrate whose main component is a.
Shown below. In the conventional configuration (θ = 0°), the amount of uneven wear, which is about 20 nm, decreases as θ increases, and when θ is 5° or more, the amount of uneven wear decreases to 5 nm.
It is saturated at about m. That is, it can be seen that the effects of the present invention can be significantly obtained by setting θ to 5° or more.

Next, using the same head as above, (a) C
o-Cr perpendicular magnetic recording tape, (b) Co-O perpendicular magnetic recording tape, (c) Co-Ni-O oblique evaporation tape, (
d) The uneven wear amount d of the head when sliding the Fe-based metal coated tape is compared with the conventional configuration (θ=0°) and the configuration of the present invention (θ
≧5°) is shown in Table 1.

[0032]

[Table 1]

[0033] As described above, the configuration of the present invention can obtain a sufficiently small value of d for any medium, and has remarkable compatibility with various media in terms of head wear characteristics, which was not possible with conventional configurations. It can be seen that this has been improved.

A similar study was carried out using Ni for the head substrates 1 and 2.
, Mn, O, and other various materials as main components, the effects of the present invention were sufficiently obtained as in the above embodiments. In addition, when the magnetic layer 3 was made of other materials such as Sendust's laminated film and was combined with the various head substrates 1 and 2 described above, results similar to those of the above embodiments were obtained. Furthermore, results similar to those described above were obtained when various media other than magnetic recording tape, such as disk media, were used.

As described above, the present invention is effective even if the respective embodiments of the laminated head and the magnetic recording medium are changed, as long as the above-described configuration and relative motion relationship exist.

[0036]

[Effects of the Invention] As shown in the above results, the magnetic recording/reproducing device having the configuration of the present invention improves the wear characteristics of the laminated metal head and improves the compatibility with various media in terms of sliding characteristics. be able to. That is, the present invention can improve one of the drawbacks of the laminated metal head, which has many advantages, and can further increase its application value.

[Brief explanation of the drawing]

FIG. 1 is a front view showing the relative running relationship between the configuration of a head and a medium according to an embodiment of the present invention.

[Fig. 2] A cross-sectional view showing a cross section in the layer thickness direction near the head gap, showing the uneven wear state of the laminated head.

[Fig. 3] Characteristic diagram showing the θ dependence of the head uneven wear amount d in one embodiment of the present invention.

[Explanation of symbols]

1 First board 2 Second board 3 Magnetic layer 4 Glass material 6 Relative traveling speed of medium

[Outside 8] 7

[Outer 9] magnetic layer thickness running component 8

[Outer 10] In-plane direction component of the magnetic layer

Claims (1)

[Claims] Claim 1: Relative running speed of a magnetic recording medium with respect to a magnetic head having a laminated structure in which a second substrate is bonded to the surface of a magnetic layer formed on a first substrate via a glass material. The magnetic recording/reproducing device is configured such that the thickness direction of the magnetic layer has a velocity component greater than or equal to Equation 1 in the direction from the second substrate toward the first substrate.