JP2002363773A - Retainer applied with dlc - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the durability of an engine by preventing the wear of a retainer for retaining an automobile fuel valve or an automobile exhaust valve to the face of a coil spring. SOLUTION: In the retainer for retaining an automobile fuel valve or an automobile exhaust valve to the face of a coil spring, the face abutting on the spring of the retainer, a diamondlike carbon film containing H or a diamondlike carbon film containing H, Si and O is formed directly, or via; (a) an intermediate layer of silicide or silicocarbide essentially consisting of at least one kind selected from the group 5A metals (V, Nb, Ta), the group 6A metals (Cr, Mo, W), Ti and Zr; or (b) a metallic film essentially consisting of at least one kind selected from the group 5A metals (V, Nb, Ta), and an Si film or a metallic film essentially consisting of Si, and formed thereon; or (c) a metallic film of at least one kind selected from the group 5A metals (V, Nb, Ta), the group 6A metals (Cr, Mo, W), Ti and Zr, and a silicon, carbide film formed thereon.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a retainer for use in a power transmission system for converting a driving force generated by a rotational motion of a cam into a reciprocating motion of a fuel valve or an exhaust valve in an internal combustion engine of an automobile or the like. About.

[0002]

2. Description of the Related Art In an internal combustion engine such as an automobile engine,
A power transmission system is used to transmit the driving force of the internal combustion engine to the camshaft, then convert the reciprocating motion of the rocker arm via the cam, and transmit this to a fuel valve or an exhaust valve supported by a compression coil spring. Have been. These valves are fixed to one end of a valve rod, and a retainer having an enlarged diameter is fixed to the other end of the valve rod, and a surface of the retainer is supported by a coil spring disposed around the valve rod. For this reason, the retainer is constantly pressed by the compression coil spring, and the valve is biased by the coil spring in a direction to always close. When the valve rod is pressed in synchronization with the rotation of the camshaft, the retainer opens the valve while pressing the coil spring to inject or exhaust fuel. At this time, the surface of the retainer slides while repeatedly receiving a high surface pressure while being in sliding contact with the spring, so that abrasion damage becomes severe. If this state progresses, it may become a source of noise or cause malfunctions such as the inability to properly operate the valve, or may cause a reduction in engine horsepower due to frictional loss, leading to a reduction in fuel efficiency. In addition, there is a possibility that galling occurs between the spring and the spring, making it unusable.

A typical example of a power transmission system for opening and closing a fuel or exhaust valve is a rocker arm type transmission system shown in FIG. 1, which is fixed to a shaft driven by a crankshaft for transmitting engine output. Cams 3 and 3 '
The cam followers 12, 12 'rotate while sliding on the lower surfaces thereof. As a result, the cam is moved to the rocker arm shafts 15 and 15 '.
The power is transmitted to one ends of the rocker arms 13 and 13 'supported by the first and second rockers to swing them. Rocker arm 13,
The other end of 13 ′ is connected to the valve 2 by compression springs 17 and 17 ′.
Power is transmitted to valve rods 21, 21 'via retainers 19, 19' which are biased in such a direction as to always close 3, 23 ', thereby causing fuel valve 23 and exhaust valve 23' to move to cams 3, 3 '. The fuel is supplied to the piston / cylinder of the engine or exhausted by opening and closing at the timing of (1).

The springs 17, 17 'and the retainers 19, 1
The contact surface 9 'receives a large frictional action and impact due to the constant expansion and contraction of the spring. Therefore, it is necessary to provide the contact surface of the retainer with sufficiently low friction and wear resistance.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an excellent wear resistance which does not cause such a problem on a contact surface of a retainer with a spring.

[0006]

According to the present invention, there is provided a retainer having the following configuration. (1) A retainer for holding a fuel valve or an exhaust valve of an automobile against a surface of a coil spring, wherein a diamond-like carbon film is formed on a surface of the retainer that contacts the spring. (2) Preferably, in the above (1), the diamond-like carbon film is composed of carbon and hydrogen and has a composition of CH.
When n is represented by a molar ratio, the diamond-like carbon film represented by 0.05 ≦ n ≦ 0.7 or containing silicon, and may contain oxygen, nitrogen, and fluorine.
When represented by xSiyOzNvFw, a diamond represented by the following formula: 0.05 ≦ x ≦ 0.7 0.01 ≦ y ≦ 3.0 0 ≦ z ≦ 1.00 0 ≦ v ≦ 1.0 0 ≦ w ≦ 0.2 It consists of at least one layer of a carbon-like film. (3) Preferably, in the above (1), the diamond-like carbon film is formed of CHxSiyOzNvFw (0.05 ≦ x ≦ 0.7 0.01 ≦ y ≦ 3.0 0 ≦ z ≦ 1.00 ≦ v ≦ 1 0.00 ≦ w ≦ 0.2) and at least two layers of a diamond-like carbon film represented by CHn (where 0.05 ≦ n ≦ 0.7), or Alternatively, a layer in which one of these compositions is continuously changed from the other composition to the other composition is formed. (4) More preferably, in the above (1) to (3), (a) a Group 5A metal (V, Nb, Ta), a Group 6A metal (a) between the retainer and the diamond-like carbon film. (B) a silicide or silicide containing at least one selected from the group consisting of Cr, Mo, W), Ti, and Zr; and (b) at least one selected from the group 5A metals (V, Nb, Ta). A metal film as a component and a Si film or a metal film containing Si as a main component formed thereon, or (c) a Group 5A metal (V, Nb, Ta) or a Group 6A metal (Cr, Mo, W) ), At least one metal film selected from Ti and Zr and a silicon carbide film formed on the metal film.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present inventors have found that when a diamond-like thin film (DLC film) is formed directly or through an intermediate layer on the contact surface of a retainer with a spring, the wear resistance of the retainer is markedly improved. Could be improved. Furthermore, by appropriately selecting the material of the diamond-like thin film and / or by using an appropriate intermediate layer, the adhesion was improved, and the wear resistance was significantly improved.

That is, in the present invention, a diamond-like carbon film containing H is formed on the contact surface of the retainer with the spring, or the retainer is used to improve the adhesion of the diamond-like carbon film to the substrate. H on the contact surface with the spring
And a wear-resistant coating made of a diamond-like carbon film containing Si. In this case, a diamond-like carbon film containing H can be further formed on the diamond-like carbon film containing H and Si, and further improvement in wear resistance can be expected. Hereinafter, the diamond-like carbon film may be abbreviated as DLC for simplicity. More preferably, the present invention provides (a) a Group 5A metal (V, Nb, Ta) and a Group 6A metal (Cr, between the contact surface of the retainer with the spring and the diamond-like carbon film. Mo,
W) a silicide or silicide mainly composed of at least one selected from Ti and Zr; (b) a metal mainly composed of at least one selected from Group 5A metals (V, Nb, Ta) A film and a Si film formed thereon or a metal film containing Si as a main component, or (c) a Group 5A metal (V, Nb, Ta) or a Group 6A metal (Cr, Mo,
An intermediate layer comprising at least one metal film selected from W), Ti, and Zr and a silicon carbide film formed thereon is provided. When such an intermediate layer is formed, the diamond-like carbon film is not particularly limited, and a diamond-like carbon film containing H, a diamond-like carbon film containing H, Si, and O, or a combination thereof can be used. it can.

As the material that can be used as the base material of the retainer in the present invention, any material conventionally used in the art can be used. These materials include, for example, various types of carbon steel and cast iron (gray cast iron, spheroidal graphite cast iron, malleable cast iron, alloy cast iron, etc.), cast steel and the like, and ultra-tough steel (SNCM42).
0, SCM440, SCM420, SCR420, H1
1), high-speed tool steel (high-speed steel: JIS standard SK)
H), alloy tool steel (die steel: SKD6, etc.), maraging steel (KMS180-20, etc.), ausform steel, stainless steel (SUS304, SUS430, 17)
-4PH), bearing steel (such as SUJ2), Al alloy (such as AC4C), and Ti alloy.

[0010] The metal used as the base material may be quenched under appropriate conditions to improve the hardness of the material. For quenching, for example, induction hardening, flame quenching, carburizing quenching and the like can be used. Further, a surface hardening treatment may be performed on these substrates or on the quenched substrate, and a diamond-like carbon film or a diamond-like carbon film may be coated thereon with an intermediate layer interposed therebetween. Examples of the surface hardening include nitriding, carburizing, and boring.

Intermediate Layer Next, the intermediate layer used in the present invention comprises (a) a Group 5A metal (V, Nb, Ta) and a Group 6A metal (Cr, Mo,
W) a silicide or silicide mainly composed of at least one selected from Ti and Zr; (b) a metal mainly composed of at least one selected from Group 5A metals (V, Nb, Ta) A film and a Si film formed thereon or a metal film containing Si as a main component, or (c) a Group 5A metal (V, Nb, Ta) or a Group 6A metal (Cr, Mo,
W), at least one metal film selected from Ti and Zr, and a silicon carbide film formed thereon.
178736, 2000-178737, 2000
177,046, 2000-178,738, 200
0-90842 and the like.

In the case of the intermediate layer (a), the composition is M
SiaCb (where M is V, Nb, Ta, Cr, M
o, W, at least one of Ti and Zr), 0.3 ≦ a ≦ 10, preferably 1 ≦ a ≦
6, 0 ≦ b ≦ 5, preferably 0 ≦ b ≦ 3, 0.3 ≦ a +
b ≦ 10, preferably 1 ≦ a + b ≦ 6. If a is larger than this and the amount of silicon increases, the adhesion to the base material deteriorates. If a is smaller and silicon is less, then DL
The adhesion to the C film becomes poor. When b is larger than this and the amount of carbon is large, the adhesion to the base material is deteriorated. When b is smaller than this and carbon is reduced, the adhesion to the DLC film is deteriorated. Further, even if a + b is larger than this, the adhesion to the base material is deteriorated.
Adhesion to the film is poor.

The intermediate layer preferably has a thickness of 2 nm to 5 μm, and more preferably 5 nm to 1 μm. With such a thickness, the adhesion is improved. On the other hand, if the intermediate layer is too thin, the effect of improving the adhesion will not be sufficient, and if it is too thick, the impact resistance will deteriorate.

The intermediate layer of the present invention can be formed by a PVD method such as a vacuum evaporation method, a sputtering method, an ion plating method, or a thermal CVD method.
It can be formed by a CVD method such as a plasma CVD method, a photo CVD method, or the like. Wet plating, thermal spraying,
It may be formed by clad bonding or the like. Specifically, a known method is used. In particular, the intermediate layer of the present invention is preferably formed by a sputtering method. In this case, using a target corresponding to the target composition, high-frequency power, AC power, or any of DC power is added, the target is sputtered,
This is sputter deposited on a base material (substrate) to form an intermediate layer.

Usually, the target may have the same composition as that of the intermediate layer, but it may be a multi-source sputtering using a metal such as Ta and Si as a target, or a case where C or Si is introduced by reactive sputtering. The target which does not contain the component can be used.

As the sputtering gas, an inert gas used in a usual sputtering apparatus can be used. Above all, Ar, K
r or Xe, or at least one of these
It is preferable to use a mixed gas containing at least one kind of gas.
Reactive sputtering may be performed. When carbon is introduced as a reactive gas, CH ₄ , CH ₂ , C
_{When 2} H ₄ , CO or the like is used to introduce silicon, a silane gas or the like is used. When hydrogen is introduced, H ₂
And so on. When these reactive gases are used alone,
Mixtures of more than one species may be used. The operating pressure during sputtering is preferably in the range of 0.2 to 70 Pa. Further, by changing the pressure of the sputtering gas within the above range during the film formation, an intermediate layer having a concentration gradient can be easily obtained.

As the sputtering method, a high frequency sputtering method using an RF power source or a DC sputtering method may be used. The power of the sputtering apparatus is about 0.5 to 30 W / cm ^{2 for} DC sputtering, 1 to 50 MHz for high frequency sputtering, and 50 kHz to 1 MHz for low frequency.
It is preferably about 0.5 to 30 W / cm ² . The deposition rate is 1
The range of -300 nm / min is preferable. Further, the substrate temperature is preferably 10 to 150 ° C.

Further, the intermediate layer of the present invention may be formed by a vapor deposition method. The evaporation method may be a resistance heating method or an electron beam heating method. The evaporation source is Ta
Or a single vapor deposition using the same composition as the intermediate layer. 1
Even in the original deposition, a film composition substantially the same as the composition of the deposition source can be obtained stably with time. The conditions for vacuum deposition are not particularly limited, but the degree of vacuum is preferably 10 ⁻³ Pa or less, particularly preferably 10 ⁻⁴ Pa or less. The deposition rate is usually 1 to 300 nm / m
In degree is preferable.

The intermediate layer can also be formed by a plasma CVD method or an ionization vapor deposition method.
The film may be formed with reference to the LC film.

Diamond-like carbon film A diamond-like carbon (DLC) film is sometimes called a diamond-like carbon film, an i-carbon film or the like. The diamond-like carbon film is disclosed in, for example, JP-A-62-14.
Nos. 5646 and 62-145647, New
Diamond Forum, Vol. 4 No. 4 (Showa 6
Issued October 25, 2013).

The DLC film is described in the above-mentioned document (New Diam).
as described in Raman
1550 cm for spectroscopic analysis^-1(15
20-1560cm^-11) having a peak of Raman absorption;
333cm^-1Diamonds with sharp peaks at
581cm^-1Graphite with a sharp peak at
It is a substance with a distinctly different structure. DLC film
The absorption peak in Raman spectroscopy is 1 as described above.
550cm ^-1Broad to (1520 ~ 1560cm^-1)
But has the above-mentioned elements other than carbon and hydrogen.
By having, from now on ± 100cm^-1Fluctuate
In some cases. The DLC film mainly contains carbon and hydrogen.
A thin film in an amorphous state, wherein the carbon-to-carbon sp3
Formed by the random presence of bonds
You. The DLC film is composed of carbon and hydrogen, and its composition is C
When Hn is represented by a molar ratio, it is represented by 0.05 ≦ n ≦ 0.7.
Is done.

In the present invention, the thickness of the DLC film is usually 1 to 10000 nm, preferably 10 nm to 3 μm.
It is.

The DLC film may contain one or more of O, N, and F in addition to Si in addition to carbon and hydrogen. When using without an intermediate layer, at least the first layer should contain Si in addition to hydrogen in order to improve the adhesion to the substrate. In this case, when the basic composition is expressed as CHxSiyOzNvFw, x, y, z, v, and w each represent a molar ratio of 0.05 ≦ x.
≦ 0.7, 0.01 ≦ y ≦ 3.0, 0 ≦ z ≦ 1.0, 0
It is preferable that ≦ v ≦ 1.0 and 0 ≦ w ≦ 0.2.
Also, a plurality of layers may be formed.
From a portion containing i to a portion not containing Si,
The composition may be continuously variable in the thickness direction.

The DLC film can be formed by a plasma CVD method, an ionization vapor deposition method, a sputtering method, or the like. DL
When the C film is formed by a plasma CVD method, the C film can be formed by a method described in, for example, JP-A-4-41672. Plasma in the plasma CVD method may be either direct current or alternating current, but it is preferable to use alternating current. The alternating current can be used from a few hertz to a microwave. In addition, E described in diamond thin film technology (published by Comprehensive Technology Center), etc.
CR plasma can also be used. Further, a bias voltage may be applied.

When the DLC film is formed by the plasma CVD method, it is preferable to use the following compound as a source gas. Methane, as a compound containing C and H,
Hydrocarbons such as ethane, propane, butane, pentane, hexane, ethylene, propylene and the like can be mentioned. Compounds containing C, H and Si include methylsilane, dimethylsilane, trimethylsilane, tetramethylsilane, diethylsilane, tetraethylsilane, tetrabutylsilane, dimethyldiethylsilane, tetraphenylsilane,
Examples include methyltriphenylsilane, dimethyldiphenylsilane, trimethylphenylsilane, trimethylsilyl-trimethylsilane, and trimethylsilylmethyl-trimethylsilane. These may be used in combination, or a silane compound and a hydrocarbon may be used. Compounds containing C + H + O include CH ₃ OH, C ₂ H ₅ OH, HCHO, CH ₃
COCH _{3 and the} like. Examples of the compound containing C + H + N include ammonium cyanide, hydrogen cyanide, monomethylamine, dimethylamine, allylamine, aniline, diethylamine, acetonitrile, azoisobutane, diallylamine, ethylazide, MMH, DMH, triallylamine, trimethylamine, triethylamine, triphenylamine and the like. is there. In addition, Si + C + H, Si
A compound containing + C + H + O or Si + C + H + N may be combined with an O source or an ON source, an N source, an H source, or the like.

O source, O ₂ , O _3, etc .; C + O source, CO, CO _2, etc .; Si + H source, SiH _4, etc.
As a source, H ₂ or the like, H + O source, H ₂ O, etc., N source, N ₂ N + H source, NH ₃ or the like, N + O source, N
Compounds of N and O, such as O, NO ₂ and N ₂ O, which can be represented by NOx, such as (CN) ₂ as an N + C source, NH ₄ F as an N + H + F source, and OF ₂ , O ₂ F ₂ as an O + F source. , O
₃ F ₂ or the like may be used.

The flow rate of the raw material gas may be appropriately determined according to the type of the raw material gas. The operating pressure is typically between 1 and 70
Pa and the input power are usually preferably about 10 W to 5 kW.

The DLC film may be formed by an ionization vapor deposition method. The ionization deposition method is described in, for example, Japanese Patent Application Laid-Open No. 58-17 / 1983.
No. 4507, JP-A-59-174508 and the like. However, the present invention is not limited to the methods and apparatuses disclosed therein, and another type of ion vapor deposition technology may be used as long as the ionized gas for the raw material can be accelerated. As a preferable example of the device in this case, for example, an ion straight type or an ion deflection type described in Japanese Utility Model Laid-Open No. 59-174507 can be used.

In the ionization vapor deposition method, the inside of the vacuum vessel is set to a high vacuum of about 10 ^-4 Pa. A filament that is heated by an AC power supply and generates thermoelectrons is provided in the vacuum vessel. A counter electrode is arranged around the filament, and a voltage Vd is applied between the filament and the filament. In addition, an electromagnetic coil that surrounds the filament and the counter electrode and generates a magnetic field for trapping ionized gas is arranged. The source gas collides with the thermoelectrons from the filament to generate positive thermal decomposition ions and electrons, and the positive ions are accelerated by the negative potential Va applied to the grid. By adjusting Vd, Va and the magnetic field of the coil, the composition and film quality can be changed. Further, a bias voltage may be applied.

When the DLC film is formed by the ionization vapor deposition method, the same material gas as that used in the plasma CVD method may be used. The flow rate of the source gas may be appropriately determined according to the type. The operating pressure is usually 1 to 70 Pa
The degree is preferred.

The DLC film can be formed by a sputtering method. In this case, a gas such as O ₂ , N ₂ , NH ₃ , CH ₄ , H ₂ or the like is introduced as a reactive gas in addition to a sputtering gas for sputtering such as Ar or Kr, and C, Si,
Targeting SiO ₂ , Si ₃ N ₄ , SiC, etc.
A target may be a mixed composition of C, Si, SiO ₂ , Si ₃ N ₄ , and SiC, and in some cases, C, Si, N, O
May be used. Further, a polymer can be used as a target. A DLC film is formed by applying any one of high-frequency power, AC power, and DC power using such a target, sputtering the target, and sputter depositing the target on a substrate. The high frequency sputtering power is usually 50 W to 2 k
It is about W. The operating pressure is usually 10 ^{−3 to} 0.1 Pa
Is preferred.

[0032]

Next, embodiments of the present invention will be described. An intermediate layer and a DLC film were formed on the surface of the retainer. SNCM420 was used as a material for the retainer. The surface roughness of the base material of the retainer of the example was all Ra = 0.1 μm. Place the retainer in place in the vacuum chamber,
After evacuation, a film was formed under the following conditions.

<Deposition of Intermediate Layer> The intermediate layer 1 shown in Table 1 was manufactured by sputtering under the following conditions. Working gas: Ar (5.1 × 10 ^-2 Pa · m ³ · s ^-1 ) =
30 sccm Sputtering pressure: 40 Pa Input power: 500 W Target: Ta, Si Film thickness: Ta (first layer) 10 nm, Si (second layer) 9
0 nm

The intermediate layer shown in Table 1 was formed under the same film forming conditions while changing the target. When a single intermediate layer was used, the film thickness was all 100 nm.

[0035]

[Table 1]

<DLC Film Formation> A DLC film was formed by the self-bias RF plasma CVD method under the following conditions. DLC1 source gas: C ₂ H ₄ (0.017 Pa · m ³ · s ⁻¹ ) Power supply: RF Operating pressure: 66.5 Pa Input power: 500 W Film formation rate: 100 nm / min Film composition: CH _0.21 Film thickness: 2 μm DLC2 Source gas: Si (OCH ₃ ) ₄ (0.085 Pa · m ³ ·
s ^-1 ) Power supply: RF Operating pressure: 66.5 Pa Input power: 500 W Deposition rate: 100 nm / min Film composition: CH _0.2 Si _0.1 O _0.17 Film thickness: 2 μm DLC3 source gas: Si (CH ₃ ) ₄ (0. 085 Pa ・ m ³・ s
^-1 ) Power supply: RF Operating pressure: 66.5 Pa Input power: 500 W Film formation rate: 100 nm / min Film composition: CH _0.24 Si _0.22 Film thickness: 2 μm

<Evaluation Method> A durability test was performed on a retainer not coated with DLC (Comparative Example) and a retainer coated with DLC (Example) under the following conditions. Thereafter, the wear states of the retainers were compared. In the test, in an automobile engine using the OHC (but a single rocker arm type), the engine is operated by attaching a retainer to a regular position and abutting a compression spring. Condition: cam rotation speed: 9000 rpm Test time: as shown in Table 2 Maximum acting stress: 2000 MPa Operating environment: in oil This condition is much severer than the rotation speed (2000-4000 rpm) in general running of commercial vehicles. It should be noted that this is an accelerated test corresponding to the F1 level. The results were as shown in Table 2. However, the test time was terminated at a maximum of 20 hours. Life is the life of the retainer.

[0038]

[Table 2]

[0039]

In Table 1, the endurance time indicates that the operation of the engine is stopped if the endurance time is exceeded. According to the example of the present invention, it can be seen that a highly durable retainer can be provided as compared with Comparative Example 1. In particular, it can be seen that Examples 5 to 18 using the intermediate layer have particularly high durability. ADVANTAGE OF THE INVENTION According to this invention, the adhesiveness was improved by selecting the material of the diamond-like thin film coat | covered with a retainer appropriately, and / or using a suitable intermediate | middle layer, and the abrasion resistance was able to be improved remarkably. .

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a structure of a power transmission system including a retainer to which the present invention can be applied.

[Explanation of symbols]

 3, 3 'cam 12, 12' follower 13, 13 'rocker arm 15, 15' rocker arm shaft 17, 17 'spring 19, 19' retainer 21, 21 'valve rod 23 fuel valve 23' exhaust valve

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court ゛ (Reference) F01L 3/10 F01L 3/10 C (72) Inventor Seiichi Odaka 1-13-1 Nihombashi, Chuo-ku, Tokyo (72) Inventor Yasuhiro Matsuba 1-1-13 Nihonbashi, Chuo-ku, Tokyo T-Daika Inc. (72) Inventor Yasushi Hashimoto 1-13-1 Nihonbashi, Chuo-ku, Tokyo TDK Co., Ltd. (72) Inventor Izumi Miyauchi 1-13-1 Nihonbashi, Chuo-ku, Tokyo T-DC F Co., Ltd. LA23 4K044 AA02 AA03 AA04 AA09 AB10 BA02 BA18 BA19 BB01 BB03 BB04 BC01 CA11 CA13 CA14 CA18

Claims (4)

[Claims] 1. A retainer for holding a fuel valve or an exhaust valve of an automobile against a surface of a coil spring, wherein a diamond-like carbon film is formed on a surface of the retainer in contact with the spring. Retainer. 2. The diamond-like carbon film is composed of carbon and hydrogen, and when its composition is represented by a molar ratio of CHn, a diamond-like carbon film represented by 0.05 ≦ n ≦ 0.7, or , Containing silicon, and may contain oxygen, nitrogen and fluorine. When the composition is represented by CHxSiyOzNvFw, 0.05 ≦ x ≦ 0.7 0.01 ≦ y ≦ 3.0 0 ≦ z ≦ 1.0 The retainer according to claim 1, comprising at least one layer of a diamond-like carbon film represented by 0 ≦ v ≦ 1.00 ≦ w ≦ 0.2. 3. The method according to claim 2, wherein the diamond-like carbon film is made of CHxS.
iyOzNvFw (provided that 0.05 ≦ x ≦ 0.7 0.01 ≦ y ≦ 3.0 0 ≦ z ≦ 1.00 ≦ v ≦ 1.00 ≦ w ≦ 0.2) Forming at least two layers of a film and a diamond-like carbon film represented by CHn (where 0.05 ≦ n ≦ 0.7), or continuously changing from one of these compositions to the other 2. The retainer according to claim 1, wherein a layer is formed. 4. A method according to claim 1, wherein (a) a Group 5A metal (V, Nb, T) is provided between said retainer and said diamond-like carbon film.
a), a silicide or silicide containing at least one selected from Group 6A metals (Cr, Mo, W), Ti, and Zr; (b) Group 5A metals (V, Nb, T
a) a metal film mainly composed of at least one selected from a) and a Si film or a metal film mainly composed of Si formed thereon, or (c) a Group 5A metal (V, Nb, T
a) an intermediate layer comprising at least one metal film selected from Group 6A metals (Cr, Mo, W), Ti and Zr and a silicon carbide film formed thereon; The retainer according to any one of claims 1 to 3, wherein: