JPH0996367A - Disk valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a disk valve which can maintain an excellent sliding property for a long period, has an excellent abrasion-proof property, and has a long service life. SOLUTION: Hydrogen is included in a diamond form hard carbon film 34, and the hydrogen including amount is made less than 35 atomic %. That is, the diamond form hard carbon film 34 whose hydrogen including amount is made less than 35 atomic % has more than 10GPa in the Knoop hardness (HK), and as a result, it is never abraded in a short time even in the sliding condition with a movable valve body 20, and an excellent sliding property by the self lubricating function of the film 34 itself can be maintained for a long period. In this case, the expression that the hydrogen including amount in the film is less than 35 atomic %, means that along the whole body of the film 34 from the front layer to the film thickness T, the hydrogen including amount is made less than 35 atomic % uniformly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a movable valve body and a fixed valve body used in the construction of a faucet including a single lever mixing tap, a thermostat mixing tap, a hot and cold water mixing tap, a medical sampling valve, a chemical liquid valve, and the like. It relates to a disc valve consisting of.

[0002]

2. Description of the Related Art Conventionally, a disk valve constituting a water faucet, a hot and cold water mixing faucet, a medical sampling valve, or a chemical liquid valve is slidably contacted with two disc-shaped valve bodies. As a result, the fluid passage formed in each valve body is opened and closed.

For example, as shown in FIG. 7 (A), a facet valve used as a faucet or a hot and cold water mixing valve has a sliding surface 31 of a solid valve body 30 and a sliding surface of a movable valve body 20. 21 and a lubricant (not shown) such as grease is interposed between them and they are brought into sliding contact with each other, and the movable valve body 20 is moved by operating the lever 40 as shown in FIG. 2 (B). , The fluid passages 22 formed in the valve bodies 20, 30 of each other,
32 was opened and closed to adjust the flow rate of the supply fluid.

In addition, this type of valve has a smooth lever operating force without water leakage even if the standard withstand pressure of 17.5 Kg / cm ² or less specified by the Japan Water Works Association, and the lever operating force is long-term. It is required to be hard to change even in use, and in order to satisfy these characteristics, there has been one in which each valve body 20, 30 is made of ceramics.

[0005]

However, although ceramics can be machined with high precision and are excellent in wear resistance and corrosion resistance, when they lose their lubricant such as grease and become in a non-lubricated state. The sliding surfaces 21 and 31 may be caught or noise may be generated, or the lever operating force may be gradually increased, and finally the valve bodies 20 and 30 may stick to each other, causing linking (adhesion). There were challenges. Moreover, there is a risk that the lubricant such as grease may be harmful to the human body.

Therefore, in recent years, the valve bodies 20, which slide with each other,
At least one of the sliding surfaces 21, 3
1 has a self-lubricating property and is coated with a diamond-like hard carbon film having excellent wear resistance (see JP-A-3-223190).

However, in the facet valve coated with the diamond-like hard carbon film, the operating force is certainly improved, and even in a non-lubricated state, a light operating force can be obtained by the self-lubricating action. Though
The wear rate varies greatly depending on the diamond-like hard carbon film, and as a result, there is a variation in the life of each facet valve that deposits the diamond-like hard carbon film, and there is a problem that it is not possible to provide a constant quality facet valve. there were.

That is, although it has been clarified that the diamond-like hard carbon film mainly has an amorphous structure, further detailed internal structure and the like have not been sufficiently clarified.

[0009]

Therefore, the inventors of the present invention have observed and measured the diamond-like hard carbon film from various angles, and that the hydrogen content in the film formation process has a great influence on the film life. It is what has been exerted.

That is, according to the present invention, two valve bodies which slide on each other are formed of one of ceramics, metal and resin, and a diamond-like hard carbon film is formed on the sliding surface of at least one of the valve bodies. In the disk valve formed by deposition, the hydrogen content in the diamond-like hard carbon film is set to 35 atomic% or less.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to a faucet valve such as a faucet or a hot and cold water mixing tap.

FIG. 1 is a view showing only a valve body constituting a disc valve according to the present invention. A movable valve body 20 is a disc-shaped body 23 having a fluid passage 22 penetrating the upper and lower surfaces thereof, and one surface thereof is provided. Is a sliding surface 21, and the fixed valve body 30 is provided with a fluid passage 32 that penetrates the upper and lower surfaces similarly to the movable valve body 20, and is movable by a disc-shaped body 33 whose outer diameter is slightly larger than the movable valve body 20. A surface of the valve body 20 facing the sliding surface 21 is a sliding surface 31, and a diamond-like hard carbon film 34 is attached to the sliding contact surface 31.

The fixed valve body 30 and the movable valve body 2
By sliding the sliding surfaces 21 and 31 of each other in a non-lubricated state with 0 and moving the movable valve body 20 in the direction of the arrow,
The fluid passages 22 and 32 provided in the valve bodies 20 and 30 are opened and closed to adjust the flow rate of the supply fluid.

At this time, since the sliding surface 31 of the fixed valve body 30 is coated with the diamond-like hard carbon film 34 having self-lubricating property and excellent wear resistance,
The operating force of the movable valve body 20 can be greatly reduced and smooth sliding can be performed without causing water leakage.

The material for forming the fixed valve body 30 and the movable valve body 20 is made of one kind of resin, metal and ceramics. For example, when it is made of resin, polyamide imide (PAI) is used. ), Polyimide (PI), polyphenylene sulfide (PPS), polyether ether ketone (PEEK), polyamide (PA), tetrafluoroethylene resin (PTFE), polyacetal (POM), polyphenylene oxide (PP)
A resin having a Rockwell hardness of 100 or more such as O) is good, and when formed of metal, brass, stainless steel,
Cemented carbide is good.

When ceramics having excellent wear resistance are used, ceramics containing alumina, zirconia, silicon nitride, silicon carbide, or aluminum nitride as a main component are preferable, and Young's modulus of 206 is obtained by using these ceramics. Since it is 441 GPa and has a Vickers hardness (Hv) of 10 GPa or more, it is possible to obtain a facet valve that can be used for a long period of time.

In the case of producing ceramics such as those described above, the main material Al ₂
O ₃ to SiO _2, MgO, adding one or more sintering aids of CaO or the like, with respect to ZrO ₂ of the main raw material in the zirconia ceramic Y ₂ O _3, CaO, MgO,
One or more stabilizers of CeO ₂ or the like are added, and in the silicon nitride ceramics, one or more oxides or nitrides of the elements of Group 2a and 3a of the periodic table are added to Si ₃ N ₄ which is the main raw material. In the silicon carbide ceramics, C, B, Al ₂ O ₃ ,
Stabilizers such as Y ₂ O ₃ are added, and in aluminum nitride ceramics, Yb is added to AlN which is the main raw material.
_If one or more sintering aids of rare earth oxides such as ₂ O ₃ and Y ₂ O ₃ are added and fired, it is possible to obtain a ceramic that is strong and has excellent toughness and wear resistance.

Further, the sliding surface 21 of the fixed valve body 20 formed of these materials prevents the sliding surface 31 of the fixed valve body 30 from being greatly worn, and reduces the contact area to improve the sliding characteristics. On the other hand, in order to prevent water leakage while increasing it, the surface roughness is set to 0.2 μm or less in terms of the center line average roughness (Ra) and the flatness is set to 1 μm or less.

On the other hand, the sliding surface 31 of the fixed valve body 30 has a center line average roughness (Ra) of 0.15 to 0.5 μm and a flatness of 3 μm or less, preferably 1 μm or less. A hydrocarbon gas (C
CVD using paraffin hydrocarbons such as H ₄ , C ₂ H ₆ and C ₃ H ₈ and aromatic hydrocarbons such as C ₆ H ₆ )
A uniform diamond-like hard carbon film 34 is deposited by a thin film forming means such as a sputtering method, a PVD method, or a sputtering method.

Here, the reason why the sliding surface 31 of the fixed valve body 30 is in the above-mentioned surface state is that the center line average roughness (Ra) is 0.5 μm.
If it is larger than m or the flatness is larger than 3 μm, the sliding surface 21 of the movable valve body 20 is greatly worn and water leakage occurs. However, the lower limit of the surface roughness is set to 0.15 μm because the adhesion is poor and the diamond-like hard carbon film 34 may be peeled off because a sufficient anchoring effect cannot be obtained in the film formation.

By the way, the diamond-like hard carbon film 34 is synonymous with a synthetic pseudo diamond thin film, a DLC film,
It is called a diamond-like carbon film or an i-carbon film, and its structure may basically contain an amorphous structure although it may contain a small amount of crystalline material, and it is 1350 cm ⁻ when viewed by Raman spectroscopy. Position ¹ and 1550 cm
Each has a peak near the ^-1 position.
The peak position may be biased to either 1350 cm ⁻¹ or 1550 cm ⁻¹ , but it is preferably biased to a position of 1350 cm ⁻¹ close to the diamond peak position.

The diamond-like hard carbon film 34 is also used.
Although hydrogen is contained therein, in the present invention, the hydrogen content is set to 35 atomic% or less.

This is hydrogen in a hydrocarbon gas used as a film forming gas (paraffinic hydrocarbons such as CH ₄ , C ₂ H ₆ and C ₃ H ₈ and aromatic hydrocarbons such as C ₆ H ₆ ). Is mixed in the diamond-like hard carbon film 34, and the film hardness greatly changes depending on the hydrogen content. The hydrogen content can be adjusted by adjusting the flow rate of the hydrocarbon gas. However, when the hydrogen content is higher than 35 atomic%, a soft organic film is formed, and such a film can be used in a short period of time. It will be worn away.

That is, the diamond-like hard carbon film 34 having a hydrogen content of 35 atomic% or less has a Knoop hardness (Hk).
Since it has 10 GPa or more, it does not wear out in a short period even when sliding with the movable valve body 20, and it is possible to maintain excellent sliding characteristics due to the self-lubricating action of the film 34 for a long period of time. .

The hydrogen content in the film referred to in the present invention is 3
5 atomic% or less means that the film thickness is uniformly 35 atomic% or less from the surface layer portion of the film 34 to the entire film thickness T. Therefore, 35 atomic% in the depth direction from the surface layer of the film 34
Any tendency may be exhibited within the following range. For example, it may have a tendency that the hydrogen content gradually increases in proportion to the film depth from the surface layer portion of the film 34, or may have a step shape.
In this way, the hydrogen content that gradually increases from the surface layer portion is economical because the surface layer portion has high hardness and the film formation time can be shortened.

The hydrogen content in the surface layer of the film 34 is preferably 15 atomic% or less, and the Knoop hardness (Hk) in the surface layer of the film 34 is 2 or less.
Since it has 0 GPa or more, the diamond-like hard carbon film 34 having more excellent wear resistance can be obtained.

The above hydrogen content is measured by HFS.
(Hydrogen Forwardscatteri
ng analysis) device. As shown in FIG. 3, the measurement conditions of this HFS device are as follows: the diamond-like hard carbon film 34 of the fixed valve body 30 which is a sample of the He ⁺⁺ ion beam 62 of 2.275 MeV with the beam irradiation amount of 50 μC (micro coulomb). The HFS detector 66 is arranged at an angle of 30 ° with respect to the reflected He ⁺⁺ ion beam 63, which irradiates at an angle of 15 ° with respect to
The hydrogen content is then measured by detecting the H ⁺ ions 64 which are scattered after reflection. The HFS detector 66
The foil 67 placed in front of the is for removing He ⁺⁺ ions scattered with the H ⁺ ions 64.

Further, the film thickness T of the diamond-like hard carbon film 34 adhered to the sliding surface 31 of the fixed valve body 30 is 0.1 to 0.1.
The range is 2.0 μm. This is because the film thickness T is 0.1 μm.
This is because if the thickness is smaller, the film 34 is rapidly worn away due to sliding and good sliding characteristics cannot be obtained for a long time. On the contrary, if the film thickness T is larger than 2.0 μm, a huge film forming time is required. ,
This is because the diamond-like hard carbon film 34 is not practically used, and the compressive stress in the diamond-like hard carbon film 34 becomes large, so that the diamond-like hard carbon film 34 easily peels off.

As shown in FIG. 2, a soft carbon film, a silicon carbide film or the like is interposed as an intermediate film 35 between the fixed valve body 30 and the diamond-like hard carbon film 34 in order to enhance the adhesion therebetween. You may let me. That is, since the soft carbon film has almost no residual compressive stress as compared with the diamond-like hard carbon film 34, the adhesion with the fixed valve body 30 can be enhanced, and the silicon carbide film is the diamond-like hard carbon film 34. Since the coefficient of thermal expansion is close, the adhesion with the diamond-like hard carbon film 34 can be enhanced. However, in the case of such a laminated structure, the thickness T of the diamond-like hard carbon film 34 is 0.4 to 1.0 μm, and the thickness t of the intermediate film 35 is 0.2 to 1.6 μm. It is preferable to provide. Further, the intermediate film 35 is not limited to one layer, and may be two or more layers provided that it is in the range of 0.2 to 1.6 μm.

As described above, in the above embodiment, the fixed valve body 3 is used.
Although the example in which the diamond-like hard carbon film 34 is adhered to the sliding surface 31 of No. 0 is shown, conversely, the diamond-like hard carbon film 34 is adhered to the sliding surface 21 of the movable valve body 20, and the fixed valve body 30 is attached. May be made of any one of ceramics, metal, and resin, and further, the movable valve body 20 and the fixed valve body 30.
The diamond-like hard carbon film 34 having a slight difference in hardness may be applied to both of the sliding surfaces 21 and 31.

Further, in the above embodiment, an example of the faucet valve for the faucet and the hot and cold water mixing faucet is shown, but besides this, it can be used as a medical sampling valve, a chemical liquid valve, and further, a ball valve. And various other valve members, mechanical seals, bearings, sliders, and various other applications.

[0032]

EXAMPLE A valve body shown in FIG. 1 on which a diamond-like hard carbon film 34 having a varying hydrogen content in the film was adhered was manufactured as a trial,
This was incorporated into the Faucet valve shown in FIG. 7, and the durability was measured.

Each valve body 2 which constitutes a facet valve
Nos. 0 and 30 were 99% by weight of alumina powder having a purity of 96%, 0.5% by weight of SiO ₂ as a sintering aid, and Mg.
O and CaO were added in an amount of 0.2% by weight, respectively, and a binder and a solvent were further added, followed by wet pulverization, and then a granulated body having an average particle diameter of about 3.7 μm was produced by a spray dryer. The granules are molded into disk-shaped bodies 23 and 33 by a die pressing machine, and then, about 1 in an oxidizing atmosphere.
After firing at a firing temperature of 600 ° C., grinding is performed to form the fluid passages 22 and 32 having a diameter of 5 mm, and polishing is performed to make the surface of the movable valve body 20 a center line average roughness (Ra). The sliding surface 21 was formed by finishing to 0.08 μm and flatness 1 μm, and the surface of the fixed valve body 30 was finished to have center line average roughness (Ra) of 0.25 μm and flatness 3 μm to form the sliding surface 31. .

The sliding surface 31 of the fixed valve body 30 has E
CR (Electron Cyclotron Res)
once) three kinds of diamond-like hard carbon films 34 having different hydrogen contents in the film were deposited by plasma CVD method.

In order to deposit the diamond-like hard carbon film 34 using the above ECR plasma CVD apparatus, the fixed valve body 30 is held on the pedestal 52 and a vacuum pump (not shown) is used as shown in FIG. The internal gas pressure of the plasma chamber 54 and the sample chamber 55 is 0.7 mP from the attached exhaust port 61.
After the vacuum state is set to a or less, benzene gas (C ₆ H ₆ ) is introduced through the gas introduction port 60.

Next, the magnetic flux density in the plasma chamber 54 is 87
A microwave having a frequency of 2.45 GHz is introduced into the plasma chamber 54 from the waveguide 59 while the electromagnetic coil 56 is energized so as to be 5 Gs (Gauss), and plasma is generated. In order to prevent the temperature of the wall surface in the plasma chamber 54 from rising due to plasma formation, the cooling jacket 57 is previously formed.
Cooling water is circulated in the tank.

After the plasma is sufficiently generated, the shutter 58 is opened and a high frequency voltage of 13.56 MHz is applied to the fixed valve body 30 via the support member 53. A negative potential is applied,
As a result, a negative self-bias is generated in the fixed valve body 30, so that positive ions in the plasma are deposited on the surface of the fixed valve body 30 and the flow rate of the benzene gas (C ₆ H ₆ ) is adjusted, thereby 3 types of diamond-like hard carbon films 34 having different hydrogen contents were deposited. The film thickness T is 0.8 μm.

Each diamond-like hard carbon film 34 thus obtained was subjected to HFS (Hydrogen Forward).
The hydrogen content in the film was measured using a dscattering analysis) device, and as shown in FIG.
Each had a unique profile as shown in (c). However, the horizontal axis of the chart represents the depth from the film surface, and the vertical axis represents the hydrogen element content at that depth.

Further, the surface hardness of the diamond-like hard carbon film 34 shown in FIGS.
It was as shown in. However, the measurement condition of the surface hardness of the film 34 is that the test load is 25 g using a light load micro hardness meter.
f, the load load speed was 30 μm / sec, the load holding time was 5 sec, and a Knoop indenter was used as the indenter.

[0040]

[Table 1]

Then, each valve element 2 obtained as described above
While pressing the sliding surfaces 21 and 31 of 0 and 30 together with an axial force of 30 Kgf, install them in the facet valve at 80 ° C.
After sliding the hot water of 1 kg / cm ^{2 at} a pressure of 1 kg / cm ² and sliding 200,000 times, the operating force of the lever 40 of 0.8 kg or less could be maintained without abrasion of the film 34. It was judged that the durability was good. However, the operating force was the value of the push-pull gauge attached to the lever 40. The respective sliding results are as shown in FIG.

As a result, in the diamond-like hard carbon film 34 of FIG. 5A, the hydrogen content is 35 atomic% or less from the sliding surface 31 to the depth of 0.1 μm, but at the depths thereafter. The hydrogen content exceeded 35 atomic%, and the Knoop hardness (Hk) was as low as 4 GPa. As a result, the film 34 was worn out after sliding 100,000 times.

On the other hand, in the diamond-like hard carbon film 34 of FIGS. 5 (b) and 5 (c), since the hydrogen content is 35 atom% or less uniformly from the surface layer portion to the entire film thickness T, it is 200,000 times. Did not wear out until the sliding. In particular, the diamond-like hard carbon film 34 of FIG.
Has a hydrogen content of 15 atom up to 0.01 μm from the sliding surface
Knoop hardness (Hk) is 20 GP because it is below ic%
It is extremely high, and as a result, the film 34 does not wear out even after sliding 300,000 times, and the operating force of the lever 40 does not exceed 0.8 kg. Was there.

[0044]

As described above, according to the present invention, two valve bodies that slide with each other are formed of one of ceramics, metal, and resin, and at least one of the valve bodies slides. In a disk valve having a diamond-like hard carbon film deposited on its surface, by setting the hydrogen content of the diamond-like hard carbon film to 35 atomic% or less, excellent sliding characteristics can be maintained for a long period of time. Also, because it has excellent wear resistance,
A long-life disc valve can be provided.

[Brief description of drawings]

FIG. 1 is a perspective view showing only a valve body of a disc valve according to the present invention.

FIG. 2 is a perspective view showing another example of a fixed valve body 30 of the disc valve according to the present invention.

FIG. 3 is a configuration diagram showing an outline of an HFS device for measuring a hydrogen content contained in a diamond-like hard carbon film.

FIG. 4 is a sectional view schematically showing an ECR plasma CVD apparatus which is one means for depositing a diamond-like hard carbon film according to the present invention.

FIG. 5 is a chart showing the hydrogen content of various diamond-like hard carbon films, where (a) is outside the scope of the present invention, and (b) and (c) are those of the present invention.

FIG. 6 is a graph showing the relationship between the number of slides and the lever operating force.

FIG. 7 is a view showing an operating state of a general faucet valve, (A) is a perspective view in which a fluid passage is opened,
(B) is a perspective view in which the fluid passage is cut off.

[Explanation of symbols]

 20: Movable valve body 21: Sliding surface 22: Fluid passage 23: Disc body 30: Fixed valve body 31: Sliding surface 32: Fluid passage 33: Disc body 34: Diamond-like hard carbon film

Claims (1)

[Claims] 1. A two-valve element that slides on each other is formed of one of ceramics, metal, and resin, and a diamond-like hard carbon film is applied to the sliding surface of at least one of the valve elements. In the disk valve, the hydrogen content of the diamond-like hard carbon film is set to 35 atomic.
A disk valve characterized by being less than or equal to%.