JPS60138762A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To prevent damage to be inflicted on a running system even if a tape being liable to give much wear to the tape running system by coating a thin layer made of a boron nitride to a magnetic tape slide face of prescribed members in each member constituting the tape running system. CONSTITUTION:The thin layer of boron nitride is coated to the outer circumference face of a base made of stainless steel in each member of the tape running system such as a tension post 15 and tilted posts 17, 23. A drum 22 is formed by coating the thin layer of boron nitride to the outer circumference of the base of a conventional Al-made drum form. Even if a tape of a kind liable to be sticked to the tape running system such as a thin vapor-deposition tape is used, no sticking takes place. Moreover, the friction coefficient of the tape running system is small and the excellent running characteristic is ensured. No tape sticking takes place in a humid environment.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a magnetic recording and reproducing device used in a video tape recorder (hereinafter abbreviated as VTR) and the like.

[Prior art]

In recent years, technology regarding magnetic recording and reproducing devices has made remarkable progress.
In particular, the development of VTR technology is remarkable. In this situation, the current VTR systems are VHS system, β system,
Various incompatible systems, such as the V-2000 system and the CvC system, coexist and are widespread.

This creates an inconvenient problem of confusion on the user side. Against the background described above, the so-called 8# VTR is being developed as a next-generation model.
Regarding this, complete standardization has been achieved among manufacturers. The magnetic tape applied to this 8 mm VTR is a metal tape or a vapor-deposited tape. When metal tape is used, if the magnetic tape (hereinafter simply referred to as tape) running system is constructed in the same manner as that used in conventional VTRs, the metal tape will cause significant wear on various parts of the tape running system. .

On the other hand, when a vapor-deposited tape with a thin film thickness and relatively low mechanical strength is used, various other problems arise. In other words, if a tape running system is constructed in the same way as before, using a fixed post made of stainless steel or a rotating drum made of aluminum, and setting the tape winding angle to the rotating drum of φ-40m to 210Q, the tape will not be attached to the fixed post or the rotating drum. Problems arise in that the tape sticks to the circumferential surface of the rotating drum, and the coefficient of friction between the tape and the fixed post or the circumferential surface of the rotating drum increases, causing unevenness in tape running speed and, as a result, deteriorating reproduced images. Such problems become particularly noticeable when the device is used in a humid atmosphere. This kind of problem in a humid atmosphere is also disclosed in Japanese Patent Laid-Open No. 58-98868 as a general problem of VTRs, and a tentative solution is also presented. This is applied to the surface of the tape running member as a higher fatty acid such as stearic acid, as a higher fatty acid salt such as zinc stearate, as a higher fatty acid amide such as stearic acid amide, as a reactive organic amide such as a silane cobbling agent, or as a reactive organic titanium salt. For example, by dissolving a substance such as a paid titanate ester in a solvent and adjusting the concentration to about 1% by weight, the above-mentioned member is immersed in a treatment solution, and then dried with high-speed hot air to remove the substance from the surface of the above-mentioned member. A thin film layer is formed to make the member water repellent.

However, the thin film layer produced by the method disclosed above cannot withstand wear caused by running the tape for a long period of time and is therefore impractical.

〔the purpose〕

It is an object of the present invention to solve the problem that even when using a magnetic tape that is difficult to run, such as a vapor-deposited tape, the coefficient of friction in the tape running system is small, and the tape running speed becomes uneven and the tape runs smoothly. It does not stick to other components, causes less damage to the tape, provides good tape running characteristics as mentioned above even in humid atmosphere, and has the ability to wear out the tape running system like metal tape. An object of the present invention is to provide a magnetic recording/reproducing device in which damage to a tape running system can be suppressed even when a magnetic tape having a large diameter is used.

〔overview〕

In order to achieve the above object, the present invention is characterized by the following configuration. That is, among the members constituting the magnetic tape running system, at least the magnetic tape sliding contact surface of a predetermined member such as a rotating drum, a back tension post, or a fixed post is coated with a thin layer made of boron nitride. It is characterized in that it is formed by coating the base material.

〔Example〕

Hereinafter, the present invention will be clarified by examples shown in the drawings.

FIG. 1 is a system diagram showing a tape running system of a VTR which is an embodiment of the present invention. In FIG. 1, tape 10 exits from supply reel 12 in cassette 11 and takes the following path.

Cassette inner post 13 → Cassette inner post 14 → Tension post 15 → Rotating roller 16 → Inclined post 17 → Rotating roller 18 → Tape leader 19 → Full width erasing head 20
→ Tape guide 21 → Drum 22 → Inclined post 23 → Audio erase head 24 → Audio control head 25 → Post 26 → Capstan 27 and pinch roller 28 → Inner cassette post 29 → Inner cassette post 3
00 The tape 10 reaches the take-up reel 31 via the above-described route.

Among the members in the tape running system described above, for example, the tension boss I-15, the inclined post 17, and the inclined post 2
3 is the outer peripheral surface of the stainless steel base material (tape sliding surface)
coated with a thin layer of boron nitride. The drum 22 is formed by coating the outer peripheral surface of a drum-shaped base material made of aluminum with a thin layer of boron nitride, similar to the conventional apparatus of this type.

FIG. 2 is a sectional view showing the base material 41 coated with a thin layer 42 of boron nitride.

As a means for forming the thin layer 42 described above, the base material 4
It is preferable to use a method of depositing the above-mentioned substance on the surface of 1 by physical vapor deposition (PVD) or chemical vapor deposition (CVD).

FIG. 3 is a diagram showing a flowchart of the process of depositing the boron nitride by RF magnetron sputtering, which is one of the PVD methods.

First, in step 51, the sample, that is, the tension post 15. The inclined post 23 or the drum 22 is cleaned using an alkaline detergent, distilled water, and an organic solution (acetone) in this order while performing ultrasonic cleaning. Next, in step 52, the sample is soaked in isopropyl alcohol. Next, in step 53, the sample is dried in freon vapor. Next, in step 54, the dried sample is placed in a sputtering apparatus chamber. Next, in step 55, while heating the sample set in the chamber to about 2000C, the inside of the t-yambar is heated by a cryopump.
Apply back pressure to 0-7 Torr level.

Next, in step 56, Ar gas is flowed into the chamber at 10 mTorr. The target in this case is a 4-inch target with a purity of 99%.

Next, in step 57, bliss sputtering is performed for one period using a sputtering voltage from a high frequency power source, and then a sputtered film is deposited.

In the device of the present invention configured as described above, the conventional 5LJS
Instead of tension posts or inclined posts made entirely of stainless steel such as 303, a post with a thin layer of boron nitride as described above, for example, formed on the outer surface of a base material such as stainless steel, is used. Therefore, even if the wrapping angle of the tape around these posts is large, the coefficient of friction around the posts is small, and wear on both the posts and tape is extremely reduced. In conventional devices of this kind, the sum of the tape winding angles around both inclined posts (corresponding to the inclined posts 17 and 23 of the present invention) is about 1000, and the frictional resistance or The static friction force between the post circumferential surface and the tape surface became extremely large, causing problems such as uneven tape running speed and significant wear on both the post and tape, but these problems have been eliminated with the present invention. Ta. Furthermore, in the embodiment of the present invention shown in FIG. 1, the rotating drum is constructed by coating a base material made of aluminum or plastic with, for example, boron nitride. The same problem as with the posts mentioned above, which arises with respect to rli rubbing between the tape surface and the tape surface, is completely resolved.

FIG. 4 is a system diagram showing a measurement system for measuring the friction coefficient in the tape running system of the apparatus of the present invention.

In FIG. 4, a magnetic tape 100 is connected to a supply reel 10.
1 → Fixed post 102 → Guide roller 103 → Fixed post 104 → Sample (drum or post) 200 → Tension analyzer post 106 → Fixed post 107 → Capstan 108 and pinch roller 109 → Guide roller 110 → Fixed post 111 → Take-up reel They are strung out in the order of 112. Tension analyzers 121 and 122 each having a tension gauge are connected to the tension analyzer posts 105 and 106, respectively.
Signal conversion circuits 131 and 132 are connected to each of them. The outputs of each signal conversion circuit 131 and 132 are input to an arithmetic circuit 140. The distance between the tension analyzer posts 105 and 106 can be changed to be wider or narrower, so that the angle at which the tape 100 is wrapped around the sample 200 can be changed. To measure the friction coefficient μ of the sample 200 using the measuring system shown in FIG. A tension analyzer 121 detects the tension T1 of the tape on the side facing the sample 200, and a tension analyzer 122 detects the tension T2 of the tape on the side moving away from the sample 200.

Then, signal conversion circuits 131 and 132 and arithmetic circuit 1
40, the value of the friction coefficient μ is calculated by performing the calculation μm I n (T2/T 1 )/θ (θ is the angle of tape winding). When measuring the friction coefficient μ under conditions of predetermined temperature and humidity, the measurement system shown in FIG. 4 is placed in a constant temperature and humidity bath.

When the value of the friction coefficient .mu. of the tape running system of the present apparatus was measured using the above measurement system, it was found that the friction coefficient .mu. was extremely small, on the order of 0.2 to 0.3.

〔Effect of the invention〕

According to the present invention, even when a type of tape that is thin and easily sticks to the tape running system, such as a vapor-deposited tape, is applied, sticking does not occur, the friction coefficient of the tape running system is small, and good running characteristics are ensured. be done. In addition, regardless of the type of tape used, there is little friction in the tape running system, so
There is little wear on the tape, and there is also very little wear on the tape running system itself. Further, even in a humid atmosphere, the tape does not stick, and the tape running system maintains an ideal state with a small coefficient of friction. Furthermore, since the thin layer is formed using boron nitride, the hardness is increased and the coefficient of friction is further reduced.

[Brief explanation of drawings]

Figures 1 to 4 are diagrams showing one embodiment of the present invention, with Figure 1 being a system diagram showing the tape running system, and Figure 2 being a sectional view showing a state in which the base material is coated with a thin layer. , FIG. 3 is a flowchart of the process of coating with boron nitride, and FIG. 4 is a system diagram showing a system for measuring the coefficient of friction in a tape running system. 10.100...magnetic tape, 13.14.29°3
0... Post in cassette, 15... Tension post, 17.23... Inclined post, 22... Drum,
26... Post, 41... Base material, 42... Thin layer,
105゜106...Tension analyzer post, 1
21゜122...Tension analyzer, 131.1
32... Signal conversion circuit, 140... Arithmetic circuit, 20
0...Sample. Applicant's agent Patent attorney Jun Tsuboi Figure 1 Figure 2 Figure 3

Claims (7)

[Claims] (1) In a magnetic recording and reproducing device having a magnetic tape running system extending from the tape supply side to the tape winding side, at least the magnetic tape sliding contact surface of a predetermined member of each member constituting the magnetic tape running system is made of boron nitride. A magnetic recording/reproducing device characterized in that the base material of the predetermined member is coated with a thin layer of the following. (2) The magnetic recording and reproducing apparatus according to claim (1), wherein the predetermined member is a drum on which the magnetic tape is wound and run over a predetermined angle. (3) The magnetic recording and reproducing apparatus according to claim (2), wherein the drum is a rotating drum made of aluminum or plastic. (4) The predetermined member is a back tension post. The fixed post or both claims (
1) The magnetic recording and reproducing device described in item 1). (5) The magnetic recording and reproducing apparatus according to claim (4), wherein at least one of the back tension post and the fixed post is made of stainless steel and has a cylindrical shape. (6) The magnetic recording/reproducing device according to any one of claims (1) to (5), wherein the thin layer is formed by coating the base material by a physical vapor deposition method. (7) The magnetic recording/reproducing device according to any one of claims (1) to (5), wherein the thin layer is formed by coating the base material by a chemical vapor deposition method.