JPH0312886A - Sliding member for recording and reproduction - Google Patents

Abstract

PURPOSE:To improve the friction resistance and wear resistance of the sliding member by constituting the surface part of the member of a metal and the diamond-like film formed on the surface thereof. CONSTITUTION:The surface part of the sliding member is constituted of the metal and the diamond-like film formed on the surface thereof. Namely, the diamond-like film is formed on the surface of the sliding member for recording and reproducing devices. Particularly a method for forming the diamond-like film by an ionization vapor deposition method is adequate as the film forming method. The sliding member used for the recording and reproducing devices is inexpensively coated with the diamond-like film having the good friction resistance and wear resistance with good productivity in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to an improvement in a member for mounting a magnetic or optical recording/reproducing medium and a sliding member in a recording/reproducing apparatus.

More specifically, the present invention relates to a tape guide in a magnetic tape cassette, a tape guide member such as a guide roller, a half case member that contacts the medium, a center host for fixing the reel with a spring, a magnetic head, a rotating hub for an optical or magnetic disk, It also relates to friction-resistant and abrasion-resistant sliding members for parts that slide on magnetic tapes and other parts.

(Prior Art) Cassette tapes such as audio tape cassettes and video tape cassettes are provided with guide members to properly guide the running of the magnetic tape and ensure running stability. For example, fixed tape guides are provided at both ends of the front surface of the cassette. FIG. 1 is an exploded view of a conventional video tape cassette case, with only the tape guide portion shown in detail for ease of understanding.

In the figure, 2 is a lower half, 1 is an upper half, and the lower half 2 has metal halves supported by a plastic guide bin 3 and a plastic support bin 4 in order from the magnetic tape feeding side along the magnetic tape running path. a cylindrical or cylindrical fixing tape guide 5; a metal semi-cylindrical or cylindrical fixing tape guide 7 supported in a plastic support bin 6;
and a metal guide roller 9 supported by a plastic bin 8. Among these guide members, the tape guide 5.7 is particularly important. These guides are made of stainless steel (SUS3) for video use.
04, etc.), plating on a brass or aluminum base, hard resins such as polyacetal, and for audio applications, stainless steel, resins such as polystyrene, etc. are used.

Stainless steel can be worn away by the inorganic particles added to the magnetic tape backcoat when making videotape cassettes, causing dropouts, and while it is perfect for audio applications, it is very expensive. Become. Plating on a brass or aluminum base increases cost, reduces surface roughness, increases friction coefficient, and deteriorates running performance. Resin such as polyacetal is easily scraped, and due to powder falling off, it adheres to the surface of the recording medium, causing dropouts, and also tends to cause poor running due to its large coefficient of friction.

On the other hand, in the case of an optical disk or a magnetic disk, the recording medium is formed into an annular shape, and a metal rotating hub is fitted and fixed in the central hole of the disk in order to support and drive the recording medium. The rotating hub has a central hole for receiving the spindle bin from the device side and an off-axis hole for receiving the drive bin located at an eccentric position. slide the surface into the off-axis hole. At this time, wear, scratches, and dust particles occur on the surface of the hub.

FIG. 2 shows an outline of the disassembled structure of a magnetic disk device, in which a magnetic disk 14 with a rotating hub 13 fitted and fixed in a central hole, and liner sheets 15 and 16 on both sides thereof are placed between an upper case 11 and a lower case 120. Consists of storage. Rotating hub 1
3 is a rectangular central hole 17 for receiving a central spindle bin (not shown) on the playback device side, and an off-axis rectangular hole 1 for receiving a drive bottle (not shown) located at an eccentric position.
It has 8. When a disk device is installed in a recording/reproducing device, the spindle bin and drive bin automatically try to enter these holes, but these bins do not necessarily fit into the hole 17.1.
8, the drive pin rotates while sliding on the surface of the hub 13 to locate and fit into the hole. The rotating hub 13 is usually made of stainless steel (SUS430
) or coated with plating (e.g. hard chrome plating), but the parts that come into contact with the drive bottle and spindle bin gradually wear out and cause powder to fall off during repeated use. If it adheres to the disk surface, false recording or dropouts may occur, resulting in malfunctions when recording and reading information. Shutters and the like also slide each time they are used, so unless they are made durable, the above-mentioned problems will occur.

In addition, there are similar problems due to friction and wear of the magnetic head due to contact with the magnetic tape and powder falling off. In general, when sliding members in magnetic recording and reproducing devices, optical disk recording and reproducing devices, etc. are located close to the recording medium, errors occur in recording or reproducing information due to powder falling off due to wear of the sliding members. However, it is desirable to have a sliding member that is as wear resistant as possible, and in fact, by devising the material of the sliding member, one with considerably good wear resistance has been obtained.
It is further desirable that it can be manufactured easily in terms of cost.

(Object of the Invention) Therefore, the object of the present invention is to provide a tape guide member, a magnetic head, a rotating hub of an optical or magnetic disk, etc. in a magnetic or optical recording/reproducing device such as a magnetic tape cassette, an optical or magnetic disk, or a magnetic head. The object of the present invention is to provide an inexpensive means for reducing the friction and improving the abrasion resistance of a sliding member in a portion that slides on a magnetic tape or other portions.

(Summary of Structure of the Invention) The present invention provides a sliding member for use in a member for mounting a recording/reproducing medium and a recording/reproducing device, in which a surface portion of the sliding member is made of metal and a diamond formed on the surface thereof. The present invention provides a friction-resistant and wear-resistant sliding member for recording and reproducing, which is characterized by comprising a similar coating.

The sliding member of the present invention is a magnetic tape guide member of a magnetic tape cassette, a medium storage half case, a center boss for fixing a reel, a magnetic head surface that contacts the medium, and a rotating hub that supports an optical disk or a disk of a magnetic disk device. It can be applied to etc.

According to the above configuration, a sliding member used in a recording/reproducing device can be coated with a diamond-like film having low friction and good wear resistance with good productivity and at low cost.

Although the diamond-like film suitable for the present invention can be formed by various methods, ionized vapor deposition is preferably used. That is, a hydrocarbon raw material gas or a raw material gas that can generate hydrocarbons through decomposition or reaction is introduced into a vacuum, ionized, and guided to the surface of the sliding member and to the surface of the metal that will become the middle curtain. A sliding member can be constructed by depositing thereon to form a diamond-like thin film. This method is preferable to other methods because it can be carried out at low temperatures, can produce a film with good crystallinity, and can be easily mass-produced.

(Detailed Description of the Invention) As briefly mentioned above, the present invention is characterized in that a diamond-like film is formed on the surface of a sliding member for a recording/reproducing device. As the film forming method, a diamond-like film forming method using ionized vapor deposition is particularly suitable.

The ionization vapor deposition method is a hydrocarbon raw material gas or a raw material gas that can generate hydrocarbons by decomposition or reaction (here, hydrocarbons include saturated hydrocarbons such as methane, ethane, and propane, and unsaturated hydrocarbons such as ethylene, propylene, and acetylene). Raw material gases that can be decomposed to produce hydrocarbons include alcohols such as methyl alcohol and ethyl alcohol, ketones such as acetone and methyl ethyl ketone, and raw material gases that can react to produce hydrocarbon gases. There are carbon monoxide, a mixed gas of carbon dioxide and hydrogen, etc.The raw materials include rare gases such as helium, neon, and argon, and at least one of hydrogen, oxygen, nitrogen, water, carbon oxide, carbon dioxide, etc. ) is ionized into an ion flow by means such as arc discharge between a pair of cathodes or ionization by thermionic emission between a cathode hot filament and a pair of cathodes, and this flow is accelerated by an electric field to cause it to flow onto the substrate. This is a method of forming a diamond-like thin film by directing the film, and is disclosed in Japanese Patent Application Laid-Open No. 58-174507, Japanese Patent Application No. 63-59376,
As described in No. 63-59377, etc., the ionization vapor deposition method does not require the use of a high temperature of 700 °C or more as the substrate temperature (for example, "Surface Chemistry" No. 5).
Vol. 108 (1984), pp. 108-115), the film forming efficiency is good, and the formed diamond-like film has good surface properties, high hardness, high thermal conductivity, and high refractive index. This is an excellent method as it does not require surface treatment.

The ion beam can be fixed and the substrate moved, or conversely, the substrate can be fixed and the ionized hydrocarbon plasma-like ion beam deflected and scanned in a direction almost perpendicular to the original direction. can form a diamond-like thin film. Such a deflection magnetic field can be created by using a permanent magnet or an electromagnet that generates a magnetic field in a direction perpendicular to the acceleration direction of the ion stream.

The ionization vapor deposition method, which is the basic technology of the present invention, is
-59377 and No. 63-59376, etc., and the embodiments of the present invention use methods and devices based on the devices described in these documents.

Figure 3 shows a preferred example of the film forming apparatus. In the figure, 30 is a vacuum container, and 31 is a chamber, which is connected to an exhaust system 38 and drawn to a high vacuum of about 10'' Torr. 32
is an electrode provided on the back surface of the substrate S that is fed in a fixed direction by a suitable driving means, and in this case, a voltage Va is applied thereto.

33 is used to accelerate ions with a grid. 34 is a hot cathode filament, which is heated by the AC power source If to generate thermoelectrons, and is maintained at a negative potential. 35 is a supply port for hydrocarbon gas, which is a raw material. Further, a counter electrode 36 is disposed surrounding the filament 34, and a voltage Vd is applied between the counter electrode 36 and the filament. An electromagnetic coil 39 is disposed surrounding the filament 34, the counter electrode 36, and the supply port 35 to generate a magnetic field for confining the ionized gas. Therefore, the film quality can be changed by adjusting Vd, Va, and the coil current.

In addition, in FIG. 3, the hydrocarbon gas raw material introduction passage 3
A plasma excitation chamber 36 is provided at 7, thereby increasing the efficiency of the ionization device. For example, microwaves, radio frequency (RF waves), radiation, ultraviolet rays, etc. can be used for plasma excitation.

Alternatively, as shown in FIG. 4, a part of the configuration shown in FIG. 3 may be modified to place a fixed or variable strength magnet 40 above the filament 34 for use in deflecting a plasma-like ion beam. good. The magnetic field strength of the magnet 40 is fixed or variable,
The magnetic field of the magnet is set in a direction that intersects the traveling direction of the ion flow. In this way, the deflection angle θ is obtained for desired ions such as CH3 and CH4+ ions. Fixed Case 1 On the other hand, ions whose mass is significantly different from these ions, such as hydrogen ions, are bent even more, and neutral particles and heavy multimer ions travel straight. Therefore, if the mask is placed in the straight direction, only highly crystalline ions will adhere to the substrate S.

1. The film forming method will be explained in detail using the apparatus shown in FIG. First, the inside of the chamber 31 is brought to a high vacuum of 10"6 Torr, and the valve of the gas supply passage 37 is operated to supply a predetermined flow rate of methane gas, a mixed gas of methane gas and hydrogen, or a mixture of methane gas and hydrogen, or methane gas and Ar gas.
While introducing a carrier gas such as He or Ne from each supply port 35, the exhaust system 38 is adjusted to a predetermined gas pressure of 1° Torr, for example. On the other hand, a plurality of hot cathode filaments 34
An alternating current If is passed through the filament 34 to heat it, and a potential difference Vd is applied between the filament 34 and the anticathode 36 to form a discharge. Methane gas supplied from the supply port 35 is thermally decomposed and collides with thermoelectrons from the filament to generate positive ions and electrons. This electron collides with another pyrolysis particle2. By repeating this phenomenon under the confinement effect of the magnetic field of the electromagnetic coil, methane gas becomes positive ions of thermally decomposed substances.

The positive ions are attracted by the negative potential Va applied to the electrode 32 and the grid 36, are accelerated toward the slowly moving substrate S, and collide with the substrate to perform a film-forming reaction and form a diamond-like thin film. Form. If desired, even better quality thin films can be obtained using the fixed magnets described above.

For conditions such as potential, current, temperature, etc. of each part, please refer to the previously cited patent applications and patent publications as well as publicly known materials.

The thickness of the film to be formed is preferably from 100 to 10,000. If the thickness is thinner than the above range, the abrasion resistance will be reduced, and if it is too thick, the effect will not be increased and the production time will be increased.

Further, the substrate on which the diamond-like film is to be formed may be cleaned in advance by ultrasonic cleaning using an organic solvent or the like.

Next, the present invention will be explained in detail.

11 Tape Guide) The tape guide shown in Figure 1 was manufactured. First, a cylindrical body with a diameter of 3 mm was manufactured from stainless steel as the base body S of the tape guide, and this base body was loaded into the film forming apparatus shown in FIG. Then introduce methane gas and increase the gas pressure to 10-'To
A discharge was caused in the hot cathode filament as rr. The magnetic flux density of the electromagnetic coil 19 is 400 Gauss, and the substrate voltage is 30
The voltage was 0V and the substrate temperature was 200°C. Also filament 14
A current of 25 A was applied to the tube.

The filament was coiled, its width was 3 mm, the gap between it and the surrounding electrode was 8 mm, and the feed rate was 40 m.
m/hr.

A tape guide having a diamond-like film with a thickness of 0.8 μm was obtained under the conditions of If=175A, Va=30V, and Vd=−30V.

The torque, dropout, and Vickers hardness of the above tape guide were measured and were as shown in Table 1. However, the Vickers hardness was measured using a micro-Vickers meter using a weighted Log. Torque and dropout were measured by the following method.

1) Measurement of Torque A VHS tape was run at high speed, the running speed was gradually reduced, and the minimum torque required for running was measured using a torque meter.

2) Measurement of dropout We recorded 6 minutes of VHS tape and played it for 5 minutes on the actual device.
Connected or 0. Width 15μsec, depth 1 with measuring machine
The signal at 6 dB or more was measured and expressed as the number of signals per minute on average.

5 Table 1 6 This is the fluctuation range of the pulling torque. The surface flaw depth is the value after performing the attachment/detachment test 10,000 times. Vickers hardness was measured under a load of 10 g.

Table 2 The disk hub shown in Fig. 2 was manufactured using the apparatus shown in Fig. 3. First, a disk hub-shaped substrate was manufactured from stainless steel, and this substrate was loaded into the film forming apparatus shown in FIG. 3 and explained above, and a diamond-like thin film was formed on the surface of the substrate under the same conditions as in Example 1. The process was continued until a film thickness of approximately 0.5 μm was obtained. Table 2 shows the measurement results of the mechanical characteristics.

Note that the chucking torque is the torque generated by friction when sliding with the disk drive bottle, and indicates the value after conducting an attachment/detachment test 10,000 times. The sliding member of the present invention has a sliding effect when applied to a magnetic tape guide member of a magnetic tape cassette, a contacting magnetic head surface, a rotating hub that supports an optical disk or a disk of a magnetic disk device, etc. The member can be coated with a diamond-like film having good abrasion and abrasion resistance at low cost and with good productivity.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of a magnetic tape cassette equipped with a conventional tape guide, FIG. 2 is an exploded perspective view of a magnetic disk case equipped with a conventional disk hub, and FIG. 3 is an exploded perspective view of a magnetic tape cassette equipped with a conventional tape guide. A sectional view showing an example of a manufacturing device,
and FIG. 4 is a sectional view showing another example of the apparatus for producing a diamond-like thin film.

Claims (6)

[Claims] (1) In a member for mounting a recording/reproducing medium or a sliding member used in a recording/reproducing device, the surface portion of the sliding member is made of metal and a diamond-like coating formed on the surface. A sliding member for recording and playback. (2) The recording and reproducing sliding member according to item 1, wherein the member for mounting the recording and reproducing medium is a magnetic tape cassette, and the sliding member is a magnetic tape guide member. (3) The sliding member for recording and reproducing according to the above item 1, wherein the recording and reproducing device is a magnetic recording and reproducing device, and the sliding member is a surface portion of a magnetic head that comes into contact with a magnetic recording medium. (4) The recording and reproducing slide according to item 1, wherein the member for mounting the recording and reproducing medium is a case housing an optical disk or a magnetic disk, and the sliding member is a rotating hub that supports the disk. moving parts. (5) Introduce a hydrocarbon raw material gas or a raw material gas that can generate hydrocarbons through decomposition or reaction into a vacuum, ionize it using heat and an electric field to form an ion beam, and apply it to the surface of the sliding member. 2. The method for manufacturing a sliding member according to claim 1, characterized in that a diamond-like thin film is formed by depositing on a metal substrate or a plastic substrate. (6) The method for manufacturing a sliding member according to item 5, wherein the ion beam is deflected by a deflecting magnetic field in a direction perpendicular to the original direction of the ion beam.