JPH01130354A - Guide cylinder for magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To obtain a stable traveling of a tape even if a metal thin film type magnetic tape is used and to obtain a sufficient durability even in case of a still reproducing time by forming a magnetic tape sliding face by the amorphous carbon thin film having a self-lubricating property. CONSTITUTION:A guide cylinder 1 is composed of the rotary type upper cylinder 1a incorporating rotary heads 2, 2 and a fixed type lower cylinder 1b and a magnetic tape 3 travels along the tape lead 1c formed by the lower cylinder 1b. The guide cylinder 1 is taken as the amorphous carbon thin film forming a tape sliding face 1d by spattering. The friction coefft. of the tape sliding face is therefore small extremely and even if a metal thin film type magnetic tape is used a stable tape travelling is obtainable. A jitter is thus made difficult to generate and an enough durability is obtd. even at still reproducing time. Moreover the durability of the guide cylinder 1 itself can be improved because the hardness of the tape sliding face 1d is high and it is difficult to be marred.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to an ID cylinder for a magnetic recording/reproducing device such as a VTR (video tape recorder) or a DAT (digital audio tape recorder).

(b) Prior Art Guide cylinders used in conventional VTRs and DATs have been made of aluminum alloy to which silicon has been added.

The above guide cylinder is made of γ-Fe 203 or Co-y-
With coated magnetic tapes such as Fe203, stable sliding contact was maintained during tape running, and sufficient durability was obtained during still playback.

On the other hand, metal thin film magnetic tapes such as Co--Cr and Fe--Co have large residual magnetization, provide high reproduction output, and are capable of high-density recording, and are attracting attention as next-generation magnetic tapes.

However, when the metal thin film type magnetic tape is used in the guide cylinder, the following drawbacks occur.

That is, (1) metal thin film magnetic tape has a high film rigidity, and therefore, when playing back stills, the magnetic tape surface is damaged by the guide cylinder, resulting in a decrease in playback output and insufficient durability.

■ Thin metal MW magnetic tape has a large coefficient of friction, so it is difficult to obtain stable sliding contact when the tape is running, and jitter is likely to occur during playback.

etc.

In order to eliminate the above drawbacks, for example, Japanese Patent Application Laid-Open No. 57-12449
As proposed in Publication No. (Q11B15/60),
There is a method of using titanium nitride (TiN) or the like on the tape sliding surface, but it is not sufficient.

Problems to be Solved by the Invention The present invention provides a guide cylinder that can provide stable tape running even when using a metal thin film type magnetic tape and can also provide sufficient durability during still playback.

4. Means for Solving the Problems The present invention is a guide cylinder for a magnetic recording/reproducing device in which the magnetic tape sliding surface is formed of a self-lubricating amorphous carbon thin film.

(e) Effect The above-mentioned measures significantly reduce the coefficient of friction of the sliding surfaces.

(f) Example An embodiment of the present invention will be described below with reference to the drawings.

Fig. 1 is a side view of the guide cylinder, and Fig. 2 is a plan view of the same.
) and a fixed lower cylinder (1b), which contains a magnetic tape (3).
is the tape lead (1C) formed on the F cylinder (1b).
). In addition, (4H51 is a magnetic tape (3
) winding defines the corner, but it is an id pin. A major feature of the guide cylinder (IJ) of this embodiment is that the tape sliding surface (1d) indicated by diagonal lines is an amorphous carbon thin film formed by sputtering.The amorphous carbon thin film has self-lubricating properties, The coefficient of friction is 0.12 to 0.15, compared to conventional titanium nitride (
This is very small compared to 0.25 to 0.3 for TiN).

In addition, as a result of scratching tests on amorphous carbon thin film and titanium nitride thin film using a diamond needle with a diameter of 50 μm, the scratching load (load when a scratch occurs by increasing the load) was 40 t for the former and 40 t for the latter. It was 3ap.

Furthermore, a Co-Cr metal thin film type magnetic tape was attached to the guide cylinder of this example (8 txxr V T using IJ).
When recording and playing back in R, the durability time of the playback image is slow due to jitter and still playback (the initial playback output is 3 dB lower, the jitter filter is reduced to less than 1/2, and the still durability time is increased by more than 5 times) .

()) Effects of the Invention As mentioned above, the guide cylinder of the present invention has an extremely small coefficient of friction on the tape sliding surface, and even when using metal thin film magnetic tape, stable tape running can be achieved, so jitter does not occur. It is durable and has sufficient durability even during still playback, and the tape sliding surface is highly hard and scratch-resistant.
The guide cylinder itself also has excellent durability.

[Brief explanation of the drawing]

FIG. 1 is a side view of a guide cylinder in an embodiment I of the present invention, and FIG. 2 is a plan view thereof. (1)...Guide cylinder, (1a)...Upper cylinder, (1b)...Lower cylinder, (1C)...Tape lead, (1d)...Tape sliding surface, (2) (2)・
... Rotating head, (3) ... Magnetic tape, (4 bars 51
···guide pin.

Claims (1)

[Claims] (1) A guide cylinder for a magnetic recording/reproducing device in which the magnetic tape sliding surface is formed of a self-lubricating amorphous carbon thin film.