JP3393724B2 - Sliding device and forset valve - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to bearings, guide rails, air slides, bearings such as air slides and spindles, and various sliding devices such as seal members, and valve members, and more particularly to faucets, hot and cold water mixing taps, and medical sampling valves. The present invention relates to a facet valve composed of a movable valve body and a fixed valve body used in the construction of a chemical liquid valve or the like.

[0002]

2. Description of the Related Art A faucet valve used for a faucet, a hot and cold water mixing valve, a medical sampling valve, and a chemical liquid valve has two disc-shaped valve bodies which are slidably contacted with each other so that The fluid passage formed in the valve body is opened and closed. For example, a faucet valve used as a faucet or a hot and cold water mixing tap is shown in FIG.
As shown in (A), the solid valve body 30 and the movable valve body 20.
With the sliding contact surfaces 21 and 31 in contact with each other,
As shown in FIG. 4B, the movable valve body 2 is operated by operating the lever 40.
By moving 0, the fluid passages 22 and 32 formed in the respective valve bodies 20 and 30 are opened and closed to adjust the flow rate of the supply fluid.

The movable valve body 20 and the fixed valve body 3 are provided.
No. 0 requires high dimensional accuracy in order to maintain slidability and sealability, and is constantly worn against each other to open and close fluid passages. Since it is severe, it can be processed with high precision in recent years, and is formed of ceramics having excellent wear resistance and corrosion resistance.

By the way, there is a portion where the slidability and the sealability are contradictory. In order to enhance the sealability, the sliding contact surface is made extremely smooth, and a pair of valve bodies having these sliding contact surfaces are slid together. Then, there was a catch and an abnormal noise, and further, linking (adhesion) of the valve bodies sticking to each other and not moving. It has also been known that the sliding torque gradually increases as the number of sliding times increases even if linking is not achieved.

Therefore, various solutions have been proposed to prevent linking.

For example, the porosity of ceramics and the surface processing method are appropriately selected to form fine irregularities on the ceramic surface, and the pore occupancy rate or the bearing surface occupancy rate is regulated to 70 ± 10%. There are those aimed at improving the phenomenon, or those in which the valve body is made of porous ceramics having a three-dimensional mesh structure, and the open pores are impregnated with resin or oil as a lubricant (Japanese Patent Laid-Open No. 61-206875). 61-244980
No. 62-4949 No. 62-37517 No. 5
-50475).

[0007]

However, in a facet valve in which minute unevenness is formed on the sliding contact surface, it is essential to apply a lubricant to the sliding contact surface in order to maintain slidability. In addition, the lubricant deteriorates and flows out, and the base materials having irregularities slide against each other, which causes a problem that the sliding torque increases. In addition, the unevenness of the sliding contact surface wears and the bearing surface ratio increases, causing linking and increased sliding torque, and the unevenness of the sliding surface causes the lubricant to flow out. There was a problem such as impairing the sealability.

Further, depending on the type of the lubricant and the adapted fluid, the lubricant may deteriorate during long-term use, or dust, etc. may adhere, accumulate, or solidify to deteriorate sliding characteristics.

Further, tribochemical wear, which is observed when alumina ceramics are slid in water, makes the sliding surface smooth and causes linking, which may deteriorate sliding characteristics.

On the other hand, in the case where the open pores of the porous body are filled with resin, the resin portion having a low hardness is shaved first,
At this time, the edges of the hard phase forming the matrix part abrade the mating material, causing a phenomenon in which the wear of both members rapidly progresses while repeating the accumulation of wear powder and mutual transfer to the pores. Therefore, there is a problem that sliding characteristics are likely to change, particles are likely to be dropped, and the surface condition is deteriorated. As a result, the lubricating effect of the resin is not obtained and the sliding torque is increased.

Further, as a required characteristic of the facet valve, it has been conventionally required to maintain a low sliding torque over the number of sliding times of about 100,000 times, but recently it has been required to maintain up to 200,000 times. Has been. On the other hand, the above-mentioned required characteristic cannot be satisfied by the above-mentioned Faucet valve.

Therefore, in order to improve the above sliding characteristics,
Attention has been focused on an amorphous hard carbon film having excellent wear resistance and a small friction coefficient, and a sliding member in which this amorphous hard carbon film is formed on a sliding surface of a ceramic member has been proposed (Japanese Patent Laid-Open No. Hei 10 (1999) -242242). 3-223190 publication etc.). For example, in a Fawcett valve consisting of a fixed valve body and a movable valve body, in which the amorphous hard carbon film is formed on the movable valve body side, the sliding torque can be stably reduced, and the conventional ceramics It shows superior sliding characteristics compared to the Faucet valve.

However, even the forset valve provided with this amorphous hard carbon film could not sufficiently satisfy the above-mentioned required characteristics. One of the causes is peeling and abrasion of the amorphous hard carbon film.

Among these, in order to solve the problem of peeling, C
By adopting a method of forming an intermediate film between the base material and the amorphous hard carbon film by the VD method to improve adhesion, or an ion plating method of implanting an ionized element on the surface of the base material by the PVD method. , A method of improving the adhesion with the base material has been carried out.

Although the above method has greatly improved the problem of peeling, no specific method for improving wear has been proposed. Here, factors that affect the wear of the amorphous hard carbon film include an appropriate combination of mating material materials and the mutual state of the sliding surface. That is, in order to reduce the sliding torque and satisfy the above required characteristics,
The choice of mating material and the condition of the sliding surface are important issues.

Therefore, the present invention has a good sealing property, the sliding torque does not increase even after repeated sliding, and the peeling and abrasion of the amorphous hard carbon film can be reduced. An object of the present invention is to provide a sliding member and a facet valve having smooth sliding characteristics without causing linking for a long period of time.

[0017]

In the sliding device of the present invention, one sliding surface of a pair of sliding members sliding with each other is made of an amorphous hard carbon film, and the other sliding surface is A sliding device made of alumina ceramics having an alumina content of 96% by weight or more, wherein the surface roughness of the sliding surface made of the amorphous hard carbon film is 0.15 to 0 in terms of center line average roughness (Ra). ．
4 μm, the surface roughness of the sliding surface made of the alumina ceramics is made smaller than the surface roughness of the sliding surface made of the amorphous hard carbon film, and the pores of the sliding surface made of the alumina ceramics are occupied. Area ratio 6% or less,
It is characterized in that the average pore diameter is 5 μm or less.

Also, in the facet valve of the present invention, one of the fixed valve element and the movable valve element that slides on each other has a sliding surface made of an amorphous hard carbon film, and the other sliding surface contains alumina. A facet valve made of alumina ceramics in an amount of 96% by weight or more, wherein the surface roughness of the sliding surface made of the amorphous hard carbon film is 0.15 to 0.4 μm in terms of center line average roughness (Ra). And the surface roughness of the sliding surface made of the alumina ceramics is made smaller than the surface roughness of the sliding surface made of the amorphous hard carbon film, and the pore occupying area of the sliding surface made of the alumina ceramics is The ratio is 6% or less, and the average pore diameter is 5 μm or less.

That is, since the state of the sliding surface of the mating material is important in order to prevent the amorphous hard carbon film from peeling and wearing, the above conditions are limited.

First, the surface roughness of the sliding surface of the counterpart material, ceramics, is set to be equal to or less than the surface roughness of the amorphous hard carbon film. This is because they are easily worn. Specifically, when the surface roughness (center line average roughness: Ra) of the ceramic sliding surface and the surface roughness (Ra) of the amorphous hard carbon film were respectively measured, the surface roughness of the ceramic sliding surface was measured. Is less than the surface roughness of the amorphous hard carbon film.

The area occupied by the holes existing on the ceramic sliding surface is 6% or less, and the average diameter is 5 μm or less.
This is because if it is larger than this range, the amorphous hard carbon is easily damaged and abraded at the edge portions of the holes.

Further, in order to reduce the sliding torque,
High hardness ceramics is used as a sliding counterpart for the amorphous hard carbon film.

[0023]

According to the present invention, the wear of the amorphous hard carbon film can be reduced by reducing the surface roughness on the ceramic sliding surface side. Further, by reducing the occupying area and average diameter of the pores on the ceramic sliding surface, it is possible to reduce the cutting action at the pores due to elastic contact, and as a result, wear of the amorphous hard carbon film can be reduced. Furthermore, by selecting a ceramic material with high hardness and high Young's modulus as the base material and the sliding mating material that form the amorphous hard carbon film, the contact area by elastic contact shown in Hertz's elastic contact theory can be reduced. As a result, frictional force and sliding torque can be reduced.

[0024]

EXAMPLES Examples of the present invention will be described below. The same parts as those in the conventional example are designated by the same reference numerals.

FIG. 1 is a diagram showing only a valve body of a facet valve which is an example of a ceramic valve according to the present invention. FIG. 2 shows only a movable valve body 20 and FIG. 3 shows a fixed valve body 3.
It is a figure which respectively shows only 0.

Each of the movable valve body 20 and the fixed valve body 30 is a disk-shaped body made of ceramics. The fixed valve body 30 is provided with an amorphous hard carbon film 33 to form a sliding surface 31, and one of them is formed. The movable valve body 20 is a sliding surface 21 made of ceramics. The surface roughness of the sliding surface 21 is less than or equal to the surface roughness of the sliding surface 31 made of the amorphous hard carbon film 33, and the hole occupying area of the ceramic sliding surface 21 is 6% or less.
The average pore diameter is 5 μm or less.

Then, as shown in FIG. 1, the fixed valve body 30
And the movable valve body 20 are in contact with each other by the sliding surfaces 31 and 21, and the movable valve body 20 is moved to open and close the fluid passages 22 and 32 provided in the valve bodies 20 and 30. The flow rate of the fluid can be adjusted.

At this time, since the sliding surface 31 on the fixed valve body 30 side is made of the amorphous hard carbon film 33, the sliding torque is reduced, and the sliding surface 21 on the movable valve body 20 side wears the mating material. Since the surface state is such that it is difficult to prevent it, a low sliding torque can be maintained for a long period of time.

In the above embodiment, the fixed valve body 30 side is provided with the amorphous hard carbon film 33, but the movable valve body 20 side is provided with the amorphous hard carbon film and the fixed valve body 30 side is slid. The surface can also be ceramics.

Further, the valve bodies 20 and 30 are made of ceramics because they are required to be made of a material which is excellent in wear resistance and hard to be deformed, but alumina ceramics is preferable in view of high hardness and low cost. For example, it is a sintered body containing alumina as a main component and can be obtained by mixing a predetermined amount of an auxiliary agent. Specifically, for alumina, CaO, SiO
_At least one of Mg ₂ and MgO may be added, and alumina ceramics having an Al ₂ O ₃ content of 96% by weight or more are particularly preferable.

Further, in the above embodiment, only the facet valve is described, but the present invention is not limited to this. For example, although not shown in the drawings, an amorphous hard carbon film is provided on the sliding surface of one of the shaft and the bearing constituting various bearing devices, the other sliding surface is formed of ceramics, and the ceramic sliding The surface roughness of the surface may be equal to or less than the surface roughness of the amorphous hard carbon film, the pore area occupation rate of the ceramic sliding surface may be equal to or less than 6%, and the pore average diameter may be equal to or less than 5 μm. Alternatively, the present invention can be applied to various sliding devices such as a sealing device.

Experimental Example 1 Here, a test for obtaining a sliding torque was carried out by making a trial set valve of FIGS. 1 to 4.

Movable valve body 2 constituting a facet valve
0 and the fixed valve body 30 both have an Al ₂ O ₃ content of 96% by weight.
Of the alumina ceramics, and an amorphous hard carbon film 33 was formed on the surface of the substrate 34 forming the fixed valve body 30. The movable valve body 20 has an outer diameter of 30 mm and a thickness of 10 mm.
The fluid passage 22 having a diameter of 5 mm was bored in the disc-shaped body, and the fixed valve body 30 was provided with the fluid passage 32 having a diameter of 5 mm in the disc-shaped body having an outer diameter of 40 mm and a thickness of 8 mm.

As a method for forming the amorphous hard carbon film 33, benzene (C ₆ H ₆ ) gas is decomposed by arc discharge plasma in a high vacuum, and ions and excited molecules in the plasma are electrically charged by an ion accelerator. A so-called ion plating method of accelerating and depositing on the surface of the fixed valve body 30 was adopted. This is one in which a high temperature and high pressure state is locally created by accelerated collision of ions, and the amorphous hard carbon film 33 is obtained with a strong adhesion.

In the facet valve, the surface roughness (center line average roughness: Ra) of the amorphous hard carbon film 33 is changed from 0.15 to 0 by changing the surface roughness of the fixed valve body 30. 20 μm, 0.21 to 0.30 μm,
Three types of 0.31 to 0.40 μm were prepared. The thickness of the amorphous hard carbon film 33 is 0.8 μm, and if the thickness is about this, the surface roughness of the amorphous hard carbon film 33 is the same as the surface roughness of the fixed valve body 30 as the base material. It will be almost the same. When the surface roughness (Ra) is less than 0.15 μm, linking with the movable valve body 20 occurs and the surface roughness (R)
When a) is 0.05 μm, the amorphous hard carbon film 33 peels off, and stable experimental results cannot be obtained.

On the other hand, the surface roughness (Ra) of the sliding surface 21 of the movable valve body 20 is variously changed within the range of 0.03 to 0.30 μm, and the average diameter of the holes of the sliding surface 21 and Samples having different occupied areas were prepared. The surface roughness and the state of the holes were changed by changing the polishing conditions of the sliding surface. Regarding the hole occupying area and average diameter, 10 points per sample were measured using an image analyzer (Luzex) with a magnification of 400, an evaluation area of 2.32 × 10 ⁵ μm ² , and a contrast of 25%. The average value was calculated.

The fixed valve body 30 and the movable valve body 20 are combined as shown in Table 1, and 30 kgf is formed by a casing.
While pressing down with the axial force of 80
The ℃ hot water was injected at a pressure of 1 kg / cm ^2, the movable valve body 2
The operating force required to slide 0 with the operating lever 40 was measured. The length of the operating lever 40 from the fulcrum 4a to the point of action 4b was 65 mm.

The evaluation criteria for this test are the movable valve body 20.
Was slid 200,000 times with respect to the fixed valve body 30, and it was judged that the slidability was good when the maximum operating force of the operating lever 40 during the sliding was 0.8 kg or less. Each result is
It is as shown in Table 2.

As can be seen from Table 2, the surface roughness (Ra) of the sliding surface 21 of the movable valve body 20 is less than or equal to the surface roughness (Ra) of the amorphous hard carbon film 33 formed on the fixed valve body 30. Further, it was found that when the occupied area of the holes on the sliding surface 21 of the movable valve body 20 was 6% or less and the average hole diameter was 5 μm or less, excellent sliding characteristics were exhibited.

When the sliding surface after the test was observed with a microscope, abrasion was observed in the amorphous hard carbon film 33 in the combination in which the slidability was deteriorated. It is considered that this is because the edge of the hole in the sliding surface 21 of the ceramic serves as a cutting edge, and the amorphous hard carbon film 33 is worn by the abrasive action. Therefore, from the viewpoint of abrasive wear, it is necessary that the hole occupying area and average diameter of the sliding surface 21 be small, and excellent sliding characteristics can be realized in a combination that satisfies both. Further, from the viewpoint of elastic contact, both the movable valve body 20 and the fixed valve body 30 need to be ceramic materials having high hardness and high Young's modulus.

[0041]

[Table 1]

[0042]

[Table 2]

Experimental Example 2 Next, in the above-mentioned Faucet valve, the surface roughness (Ra) of the amorphous hard carbon film 33 is 0.21 to 0.30 μm.
And the surface roughness (Ra) of the sliding surface 21 of the movable valve body 20 of the mating member is 0.1 μm or less, and the Al ₂ O ₃ content of the alumina ceramics forming the movable valve body 20 is 99.
The sliding characteristics were evaluated by using four types, 9% by weight, 99.7% by weight, 96% by weight and 93% by weight.

As a result, it was observed that as the Al ₂ O ₃ content decreased, the impurity phase increased, and it was easy to generate fallen particles due to intragranular fracture and intergranular fracture, and it was observed that the particles fell during sliding. . The occurrence of this grain removal increases the surface area occupied by pores and promotes the wear of the diamond-like thin film by the fallen and crushed powder. As a result, the alumina of the substrate is exposed and the sliding torque is increased.

When the Al ₂ O ₃ content is 93% by weight, the hole occupying area ratio of the sliding surface 21 is 6 to 8%,
The average pore diameter was 5 to 6 μm, which was a large value with a standard deviation of 5 μm or more. Therefore, the sliding torque increased during the experiment and exceeded 0.8 kg.

On the other hand, when the Al ₂ O ₃ content is 96% by weight or more, the pore occupying area is 6% or less, the average diameter is 5 μm or less, and the standard deviation of the average pore diameter is also Four
The value was as small as μm or less. Therefore, the operating torque was 0.8 kg or less even after sliding 200,000 times.

[0047]

As described above, according to the sliding device of the present invention, the sliding surface of either one of the pair of sliding members sliding with each other is made of the amorphous hard carbon film and the sliding surface of the other sliding member. A sliding device whose moving surface is made of alumina ceramics having an alumina content of 96% by weight or more, wherein the surface roughness of the sliding surface made of the amorphous hard carbon film is 0,0 in terms of center line average roughness (Ra). 15
.About.0.4 μm, the surface roughness of the sliding surface made of the alumina ceramics is made smaller than the surface roughness of the sliding surface made of the amorphous hard carbon film, and 6% occupancy area ratio
By setting the average pore diameter to 5 μm or less, it is possible to make the amorphous hard carbon film less likely to be worn and peeled off, so that excellent slidability can be maintained for a long period of time.

Further, by applying the above sliding member to a facet valve, a low operating torque of 0.8 kg or less is maintained even when sliding is repeated 200,000 times or more, and excellent wear resistance and sealability are obtained. And can be used satisfactorily for a long period of time.

[Brief description of drawings]

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

FIG. 2 is a perspective view showing the movable valve body of FIG.

3 is a perspective view showing the fixed valve body of FIG. 1. FIG.

FIG. 4 is a perspective view showing an operating state of a general faucet valve, in which (A) is a view in which a fluid passage is opened,
(B) is a view in which the fluid passage is cut off.

[Explanation of symbols]

10: Faucet valve 20: Movable valve body 21: Sliding surface 22: Fluid passage 30: Fixed valve body 31: Sliding surface 32: Fluid passage 33: Amorphous hard carbon film 40: Operation lever

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-7-17784 (JP, A) JP-A-6-265030 (JP, A) JP-A-5-263952 (JP, A) JP-A-5- 79069 (JP, A) JP 4-165170 (JP, A) JP-B 7-907 (JP, B2) (58) Fields investigated (Int.Cl. ⁷ , DB name) F16K 3/00-3 / 36 F16K 11/00-11/24

Claims (2)

(57) [Claims] 1. A sliding surface of one of a pair of sliding members that slide with each other is formed by an ion plating method.
A sliding device made of an amorphous hard carbon film and the other sliding surface made of alumina ceramics having an alumina content of 96% by weight or more. The center line average roughness (Ra) is 0.15
0.4 μm, the surface roughness of the sliding surface made of the alumina ceramics is made smaller than the surface roughness of the sliding surface made of the amorphous hard carbon film, and the empty space of the sliding surface made of the alumina ceramics is set. A sliding device having a hole occupying area ratio of 6% or less and an average hole diameter of 5 μm or less. 2. A fixed valve body or a movable valve body that slides on each other has a sliding surface formed by an ion plating method.
Has been made an amorphous hard carbon film, a faucet valve other slide face is made of alumina content 96% by weight or more of alumina ceramic, the surface of the sliding surface made of the amorphous hard carbon film Roughness is the center line average roughness (Ra)
0.15 to 0.4 μm, the surface roughness of the sliding surface made of the alumina ceramics is made smaller than the surface roughness of the sliding surface made of the amorphous hard carbon film, and made of the alumina ceramics. A facet valve, characterized in that the hole occupying area ratio of the sliding surface is 6% or less and the hole average diameter is 5 μm or less.