JPS60254445A - Running guide device of magnetic tape - Google Patents

Abstract

PURPOSE:To reduce damage given to a magnetic tape contacting with a magnetic tape contacting/sliding surface so as to protect the magnetic tape, by specifying the surface shape of the magnetic tape contacting/sliding surface. CONSTITUTION:The surface shape of a magnetic tape contacting/sliding surface is finished in such a way that the pitch of fine projected sections 4 is set to 100mum or less and a uniform rugged condition, in which the rate at the halfway of the projected sections 4 by an abbot load curve is within a range from about 40% to about 60%, is set and, at the same time, the value of surface roughness is set to 0.5s or less. In order to realize this surface shape, a pipe of SUS304 which is an austenitic stainless steel is finished to have about 20s of surface roughness value by grinding and the pipe is further finished to have a surface roughness value of about 2s-4s by finish grinding with a grinder wheel, and then, the pipe is finally finished to have a surface roughness value of 0.5s or less by super-finishing work.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic tape running guide device used as a running guide for a tape recorder or the like.

BACKGROUND TECHNOLOGY AND PROBLEMS In current tape recorders, there is a tendency to reduce the relative speed between the magnetic head and the magnetic tape to perform recording and playback over a long period of time.In this case, it is necessary to prevent deterioration of recorded signals. Therefore, high-density tape is usually used.

This high-density tape is called a metal tape or vapor-deposited tape, has a coercive force of 1000 oersteds, and is as thin as 10 μWL to 13 m.

Therefore, in order to protect the high-density tape, which is a thin magnetic tape and has a thin magnetic layer, the magnetic tape running guide device that guides the high-density tape in sliding contact with the magnetic tape is attached to the surface of the guide surface that comes into sliding contact with the magnetic tape. , techniques for applying special surface treatments are known.

As an example of the known technology, US Pat. No. 4,389,010
The contents are shown in Figures 1 and 2, and the cylindrical guide column (2) K that guides the magnetic tape (1) is constructed using the following method. be.

Note (1): On the outer peripheral surface in contact with the running tape (1), there is a hemispherical protrusion (with a diameter or major axis of 0.5 to 5 μm).
3) and 10,000 to 100,00 per IgG
A cylindrical magnetic tape guide method in which there are 0 protrusions (3) with a distribution density of 5.

Among the magnetic tape guide methods described in (2) and (1), the material forming the hemispherical protrusion (3) is a metal or its oxide.

Among the magnetic tape guide methods described in (3) and (2), the above-mentioned metal is selected from chromium, nickel, tungsten, and titanium.

Among the magnetic tape guide methods as described in (4) and (2), the metal acid pellets mentioned above are) J20s, ZrO
2.

A material selected from the group consisting of Cr2O5+α-Fe203 and TiO2.

In the magnetic tape guide methods described in (5) and (1), the material containing the so-called hemispherical protrusions (3) described above is a highly hard, electrically conductive, scale-like material. What is carbon?

In the magnetic tape guide method described in (6) or (1) to (5), the hemispherical protrusion (3) is made of a material selected from aluminum, brass, ceramic, or glass. Something that is formed on wood.

As mentioned above, high-density magnetic tape can be protected by applying special surface treatment to the magnetic tape running guide device, but applying such surface treatment requires special treatment equipment and the material It is difficult to manufacture because it requires a lot of money and effort, and the product has the disadvantage of being expensive.

Purpose of the Invention In view of the above-mentioned points, the present invention provides a magnetic tape running guide device with a surface finish that is relatively easy to perform.
The purpose is to provide sufficient protection for magnetic tapes.

Summary of the Invention The magnetic tape running guide device of the present invention has a surface shape of the sliding contact surface with the magnetic tape such that the pitch of minute convex portions is 100 m or less, and the pitch of the convex portions is adjusted according to the Abbott load curve. The surface is finished to have a uniform unevenness with a half ratio in the range of 40% to 60%, and the surface roughness value is o, 53 or less. This can reduce damage to the tape and protect the magnetic tape.Example An example of the present invention will be described below with reference to FIGS. 3 to 9.

Figures 3 to 5 show the magnetic tape (1) shown in Figure 1 and the guide column (2) which is a fixed guide for the vapor deposition tape, respectively.
) is an example of the state of the sliding contact part with the guide column (2), and the surface roughness value (Rmax) of the guide column (2) is 0.
．． The shapes of the shapes at the time of 5s are modeled and shown.

In other words, even if the surface is finished so that the surface roughness value is 0.53, it may exhibit various surface shapes depending on the material and processing method, and these can be roughly classified as illustrated in Figures 3 to 5. I come to do it.

As a result of an experiment, we investigated the degree of damage to the magnetic tape (1) when the traveling magnetic tape (1) is guided in sliding contact with the guide columns (2) having such various surface shapes.
It was concluded that when the guide column (2) had the surface shape shown in FIG. 3, the least damage was caused to the magnetic tape.

The surface shape shown in Figure 3 has a surface roughness value of 0.5.
3, the height h of the convex portion (4) is within 0.5 μm, and the pitch P is about 100 m to 50 m,
When the roughness curve of the surface shape shown in FIG. 3 is calculated and the Abbott load curve is calculated, it is expressed linearly as shown in FIG. 6.

That is, as for the surface shape, the pitch of the convex portions (4) is 10.
Convex part (4) in Abbott load curve from 0 m to 50 μm or less
The ratio at half (0.25 m in Figure 6) is 40% to 6
At about 0%, it becomes a uniform uneven state.

In this example, in order to achieve the surface shape shown in Fig. 3 (the Abbott load curve thereof is shown in Fig. 6), we used SUS 3, which is an austenitic stainless steel.
04 pipe is ground to a surface roughness value of about 20s, then finished by finishing grinding with a grinder to a surface roughness value of about 2s to 4s, and then finished to a surface roughness value of 0.5s or less by super finishing processing. It is.

In this example, grinding, polishing, etc. for the surface finishing of the guide column (2) were performed in the longitudinal direction (thrust direction) of the guide column (2). This is different from the conventional guide column (2).
This is because it has been confirmed through experiments that the damage caused to the magnetic tape (1) is less than when the surface is finished by grinding, polishing, etc. along the circumferential direction of the magnetic tape (1).

General grinding and polishing methods can be used to achieve this surface finish, and the surface roughness value is also 0.
．． 53, it can be mass-produced without difficulty in terms of processing work.

A surface roughness meter (manufactured by RANK TAYLORHOBSON KK) was used to measure the surface roughness of the surface finished as described above and configured as shown in Figures 3 and 6.
With the product name "Talysurf", the radius of the stylus tip is set to 2.5.
The measurement results measured at Pm are shown in FIG. 9, and it is understood that the required surface shape is formed.

In FIG. 9, one scale H in the vertical direction is 1 μm, and one scale V in the horizontal direction is 500 μm, the line on the left side of the figure shows actual measured values, and the line on the right side shows the Abbott load curve.

In the case of the surface shape of the guide column (2) configured as shown in FIG. 3, FIG. 6, and FIG. It is thought that the contact pressure between the surface of the magnetic tape (1) and the surface of the pillar (2) is dispersed and does not strongly hit one spot, thereby reducing damage to the magnetic tape (1). It was confirmed by observation with an electron microscope that the magnetic tape (1) suffered little damage.

Furthermore, as a result of the experiment, the magnetic tape (1) of the guide column (2)
Even if the sliding surface is worn or partially scratched,
In addition to being able to maintain its initial characteristics for a long time, magnetic tape (1)
It was also possible to reduce the occurrence of running problems such as sticking.

Next, to explain what is shown in FIG. 4 for comparison with this example, the surface shape in which convex portions (4) are scattered at intervals in this way is formed by surface treatment under certain conditions. Something,
The Abbott load curve is a concave curve as shown in FIG.

In the surface shape as shown in FIG. 4, the convex portions (4) with wide intervals cause a lot of damage to the magnetic tape (1). Especially when the pitch P on the roughness curve is about 5
When the thickness exceeds 00 μm, the damage becomes significant. This is because the magnetic tape (1) is strongly pressed against the convex portion (4), and the surface shape of the guide column (2) is as shown in Figure 3 (Abbott load curve Figure 6). unfavorable compared to

In addition, in the case shown in Figure 5, minute recesses (5) have been formed.Such a surface shape is seen after grinding or polishing a ceramic material, and the recesses (5) are formed by crystal grains in the ceramic bulk. This is a gap caused by a field, etc.

With such a surface shape, the Abbott load curve becomes a convex curve as shown in FIG. In the surface shape shown in Fig. 5, the magnetic tape (
1), the surface of the guide column (2) is scraped off, and magnetic powder accumulates in the recess (5), which becomes a protrusion and scrapes the magnetic surface, causing significant damage to the magnetic tape (1), resulting in a change in the surface shape of the guide column (2). is less preferable than that shown in FIG.

Effects of the Invention According to the magnetic tape running guide device of the present invention, by making the surface shape uniform and densely uneven, damage to the magnetic tape in sliding contact with the device can be reduced and the magnetic tape can be protected. be.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an example of a conventional magnetic tape running guide device, FIG. 2 is an enlarged sectional view of the main part thereof, and FIG. 3 is a main part showing an example of the magnetic tape running guide device of the present invention. 4 and 5 are enlarged sectional views of the main parts of the reference example, and FIG. 6 is an Abbott load curve diagram corresponding to FIG. 3.
Figure 7 is an Abbott load curve diagram corresponding to Figure 4, Figure 8 is an Abbott load curve diagram corresponding to Figure 5, and Figure 9 is an Abbott load curve diagram corresponding to Figure 3.
FIG. 3 is a curve diagram showing actually measured values for an implementation having a configuration corresponding to the figure. (1) is a magnetic tape, (2) is a guide column, (4) is a convex portion, and (5) is a concave portion. Figure 1

Claims (1)

[Claims] The surface shape of the sliding contact surface with the magnetic tape is such that the pitch of minute convex portions is 100. The surface roughness value should be 0.5 s or less, and the surface roughness value should be 0.5 s or less. A running guide device for a magnetic tape, characterized in that the surface is finished so as to be smooth.