JPH0672667B2 - Valve body for valve - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a valve body for a valve for communicating or blocking a fluid passage, and more particularly, the present invention relates to carbon fluoride in open pores of a ceramic porous body. The present invention relates to a valve body for a valve filled with.

(Prior Art) By relatively moving a moving valve body in a state of sliding contact with a fixed valve body housed in a valve body by operating an operation lever, communication or blocking of a fluid passage, in other words, opening and closing, Many valves have already been proposed for controlling switching, adjustment, mixing, and the like.

By the way, there are the following various demands for this type of valve.

Even when the fixed valve body and the movable valve body are always in sliding contact, the operation lever can be operated lightly.

Being able to maintain light operation with the operating lever for a long period of time.

Maintenance of each valve should be easy, and if possible, completely unnecessary.

As a matter of course, the adhesion between the valve elements does not change, and there is no fluid leakage even after long-term use.

The manufacture of each valve body is simple.

In various valves for fluids that have already been proposed in the past, for example, valves for hot and cold water mixing valves, in consideration of the wear resistance between the valve bodies, each valve body is made of, for example, an aluminum oxide sintered body or the like. Many of them were made of relatively hard materials. By doing so, the wear resistance of each valve element is improved, but the sliding between the valve elements is not smooth, and the sliding torque applied to the operation lever of the hot and cold water mixing valve becomes considerably large in the initial stage.
In order to make this sliding smooth, a lubricant is applied to the surface of each valve element, but the lubricant applied to such a surface is easy to flow out, and it may be It is difficult to maintain the operating characteristics of.

(Problems to be solved by the invention) As described above, although ceramics themselves have high hardness and excellent wear resistance, they are generally poor in self-lubricating property. It has not been proposed as a material applicable to the valve body.

The present invention has been made in view of the above circumstances, and an object thereof is to keep the fluid communication / interruption operation by the operation lever always light and stable even when used for a long period of time. The object is to provide a valve body for a valve that can be operated.

(Means for Solving Problems) Hereinafter, the present invention will be described in detail.

The valve body for a valve of the present invention is fixedly housed in the valve body to form a fluid flow path, or by relatively moving the valve body in contact with the fixed valve body by an operation lever of the valve body. It is used for at least one of the moving valve bodies that are designed to communicate or block the passage of the fixed valve body, and at least the sliding contact surface portion has an open porosity of 5 to 55% by volume and an average pore diameter. Is 0.1 to 100 μm, and the open pores of the ceramic porous body are filled with carbon fluoride.

By the way, the valve body for a valve of the present invention is formed by forming a ceramic powder as a starting material into a green shaped body of an arbitrary shape, and bonding it without blocking the pores present in the green shaped body to form a ceramic porous body. Then, it is manufactured by filling the open pores of the ceramic porous body with carbon fluoride. As will be understood from the examples and comparative examples of the present application, this carbon fluoride can improve the self-lubricating property of ceramics, and is therefore essential to the configuration of the present application.

Various methods can be applied as a method of forming the ceramic powder into a green shaped body having an arbitrary shape and bonding the pores existing in the green shaped body without blocking the pores. Binding or pressure sintering for self-sintering, addition of a substance that produces ceramics by reaction to ceramics powder for reaction sintering, ceramics powder such as metal such as Co, Ni, Mo or glass cement A method in which a binder is mixed and then pressure-sintered or pressure-sintered to bond, or a method in which a thermosetting resin or a thermoplastic resin is mixed as a binder into ceramic powder and bonded is applicable.

The ceramic porous body needs to have an open porosity of 5 to 55% by volume. The reason is that when the open porosity is lower than 5% by volume, the substantial amount of the lubricant filled becomes small, and it is difficult to sufficiently exert the lubricating characteristics, while when it is higher than 55% by volume, the porosity is increased. This is because not only the strength of the particulate material is low and particles are easily detached, but also the lubricant is easily detached.

The average pore diameter of the ceramic porous body is 0.1 to 100 μm.
m. The reason is that if the average pore size is smaller than 0.1 μm, it becomes difficult to fill the lubricant, and even if it is filled only in the vicinity of the surface, the reliability tends to be low for long-term use. If it is larger than 100 μm, the filling becomes easy, but the unevenness of the sliding contact surface becomes severe, and the pressure resistance tends to be lowered. Above all, 0.5 to 50 μm gives a better result.

The lubricant is preferably filled in the pores of the ceramic porous body at least 10% by volume of the pore volume. The reason is that if it is less than 10% by volume, it is difficult to sufficiently exert the lubricating effect of the lubricant.

Examples of the porous ceramic body include Al ₂ O ₃ , SiO ₂ , and ZrO.
₂ , cordierite, mullite, SiC, TiC, TaC, B ₄ C, W
C, Cr ₃ C ₂ , Si ₃ N ₄ , BN, TiN, AlN, TiB ₂ , ZrB ₂ , CrB ₂ ,
A ceramic mainly containing one or two selected from sialon, TiO ₂ and these compounds is preferable. This is because all of these ceramics have high hardness, thermal shock resistance, and excellent wear resistance, among which Al ₂ O ₃ , SiC, Si ₃ N ₄ , AlN,
It is more preferable to mainly contain at least one selected from sialon, ZrB ₂ or these compounds.

As a method of filling carbon fluoride into the ceramic porous body, a method of finely grinding the lubricant and sliding it into the porous ceramics, a method of dispersing the finely divided powder in a solvent, and an organic binder or an inorganic binder Can be used, and the liquid is impregnated into the porous body, then the solvent is removed, and the binder is heat-cured to fix the binder to the ceramics.

In addition, carbon fluoride can be synthesized by reacting carbon-containing ceramics with a fluorine compound.

As a means for filling the ceramic porous body with carbon, a method of filling a resin and thermally decomposing it to leave free carbon can be used, for example, phenol resin, lignin sulfonate, polyvinyl alcohol, corn starch, and the like. , Tar / pitch, heavy oil, unsaturated polyester resin, epoxy resin, furan resin, diallyl phthalate resin, urea resin, melamine resin, xylene resin, polyimide resin, polyurethane resin, polydivinylbenzene resin, aromatic compound Carbon can be filled by thermally decomposing after filling a condensed polycyclic polynuclear aromatic resin using a heavy oil or tar / pitch, polyvinyl chloride, or the like.

The present invention can also be manufactured by mixing the lubricant before firing the ceramic porous body and firing the mixture.

(Operation of the Invention) The valve element for a valve of the present invention has the following operation by being configured as described above.

First, by forming the sliding contact surface portion of at least one of the fixed valve body and the movable valve body with a ceramic porous body, the porous body itself has high hardness and is excellent in wear resistance. Therefore, the wear resistance of these fixed valve body and moving valve body is improved.

Further, at least one of the fixed valve body and the movable valve body has a sliding contact surface portion formed of a ceramic porous body having open pores of a three-dimensional mesh structure, and the open pores are filled with carbon fluoride. By
Due to the lubricity of this lubricant, the fixed valve body and the movable valve body can smoothly slide for a long period of time.

Further, in the valve, since each fixed valve element or moving valve element itself is filled with fluorocarbon as a lubricant, there is no maintenance such as applying a lubricant to each valve element as in the conventional case. Unnecessary.

(Example) Next, regarding the case where the present invention is applied to the fixed valve body (13) or the movable valve body (14) in the hot and cold water mixing valve (10),
A description will be given with reference to the drawings. Figure 1 shows a hot and cold water mixing tap (10)
A vertical cross-sectional view of the hot water / water mixing plug (10) is provided, and the water or hot water supplied to the hot water / water mixing plug (10) is used alone, or these are appropriately mixed and led out from the faucet (18).

A support member (12) is housed in the valve body (11) of the hot and cold water mixing valve (10), and a fixed valve body (13) is fixedly disposed on the support member (12). Further, a movable valve body (14) is arranged on the fixed valve body (13). A connecting member (15) is fixed to the upper part of the moving valve body (14), and when the operating lever (16) engaged with the connecting member (15) is moved by the operating lever (17), the moving valve is moved. The body (14) can be slid forwards, backwards, leftward and rightward in a state of being in close contact with the fixed valve body (13). Of course, the supporting member (12), the fixed valve body (13), the movable valve body (14) and the connecting member (15) may be integrally formed, respectively. This sliding contact surface portion of the above-mentioned structure may be formed by a ceramic porous body having open pores of a three-dimensional mesh structure as described later, and the open pores may be filled with a lubricant.

The fixed valve body (13) and the movable valve body (14) are shown in FIGS.
As shown in the figure, each has one or more passages (13a) and passages (14a) formed therein. The passage (13a) or the passage (14a) mixes water and hot water by the movable valve body (14) slidingly moving with respect to the fixed valve body (13) by the operation of the operation lever (17). The number and position of them are set so that they can be selectively performed. Of course, these passages (13a) or passages (14a)
May be a through hole or may be a simple recess.

Further, FIG. 4 shows a vertical sectional view of a single faucet (20) using the fixed valve body (13) and the movable valve body (14) according to the present invention. In this single faucet (20), a fixed valve body (13) is arranged via packing on a partition wall (23) between the primary side passage (21) and the secondary side passage (22) of water. The movable valve body (14) is arranged on the fixed valve body (13).
The movable valve body (14) is rotated in a state of being in close contact with the fixed valve body (13) by operating an operation lever (27) provided on the valve body (24) of the single faucet (20). As shown in FIG. 5, the pair of passages (13
It has a recess (14b) on its lower surface that selectively connects (a) or blocks this communication. That is, the recess (14b) of the movable valve body (14) is replaced by the passage (13) of the fixed valve body (13).
In contrast to a), when the positional relationship shown in FIG. 6 is established, the communication between the primary side passage and the secondary side passage (22) can be cut off, and the positional relationship shown in FIG. In this case, the primary passage (21) and the secondary passage (22) can be communicated with each other.

As shown in FIG. 8, a blocking projection portion (14c) capable of covering each passage (13a) of the fixed valve body (13) is formed on the lower surface of the moving valve body (14), and a passage ( 14d), and the blocking protrusion (14c) is fixed valve body (13).
The primary passages (21) and the secondary passages (22) are made to communicate with each other (13a) in the positional relationship shown by the solid line in FIG. When there is the positional relationship shown by the phantom line, the primary passage (21) and the secondary passage (2
It may be carried out by blocking communication with 2).

At least one of the fixed valve body (13) and the movable valve body (14) as described above has a sliding contact surface portion formed of a ceramic porous body having open pores of a three-dimensional mesh structure. The open pores are filled with carbon fluoride as a lubricant.

Next, examples and comparative examples in the case of actually manufacturing the fixed valve body (13) and the movable valve body (14) mainly made of silicon carbide as ceramics will be described.

Example 1 The silicon carbide powder used as a starting material contained 95% by weight of β
Formed crystals, mainly containing 0.29% by weight of free carbon, 0.17% by weight of oxygen, 0.03% by weight of iron, 0.03% by weight of aluminum, having an average particle size of 0.28 μm, no boron detected It was

To 100 parts by weight of silicon carbide powder, 5 parts by weight of polyvinyl alcohol and 300 parts by weight of water were added, mixed in a ball mill for 5 hours and then dried.

An appropriate amount of this dry mixture was sampled, granulated, and then molded at a pressure of 1000 kg / cm ² using a metal pressing die. The dimensions of this green form were φ38 × 15 mm and the density was 2.0 g / cm ³ (62% by volume).

The green molded body was placed in a graphite crucible and fired in an argon gas atmosphere as a seed of 1 atm using a Tammann type firing furnace. In the temperature raising process, first, the temperature was raised to 2000 ° C at 450 ° C / hour, and the maximum temperature of 2000 ° C was maintained for 10 minutes.

The density of the obtained porous body was 2.05 g / cm ³ , and the open porosity was 36.
The linear shrinkage for the green body was within the range of 0.25 ± 0.02% in any direction, and the dimensional accuracy of the porous body was within ± 0.05 mm. The average flexural strength of this porous body was 18.5 kg / mm ² , and the average pore diameter was 43 μm.

After processing this porous body into a ring shape with an outer diameter of 30 mm, an inner diameter of 15 mm, and a thickness of 5 mm, tar pitch with a carbon content of 80% was vacuum-pressure impregnated at 400 ° C, and the Carbonized under active atmosphere. The ratio of carbon impregnated in the porous body in the open pores was about 45% by volume.

This silicon carbide ceramic was reacted in an F ₂ atmosphere at 400 (° C.) for 1 hour to fluorinate the filled carbon by 80% by weight to form a fluorinated carbon.

A dry sliding test was performed on a porous stainless steel (SUS304) filled with this carbon fluorocarbon by a ring-on-ring method of sliding at a sliding speed of 500 mm / sec and applying an end face load of 10 kgf / cm ^2. When I went, the friction coefficient was 0.03 to 0.
05, the wear coefficient is 1.3 × 10 ^-4 mm / km (kgf / cm ² ),
It was confirmed that it had extremely excellent sliding characteristics.

Comparative Example 1 The porous body was the same as in Example 1, but a sliding test was conducted without filling a lubricant, and the friction coefficient was 0.5 to
The wear coefficient was 0.7 and the wear coefficient was 1.1 × 10 ^-1 mm / km (kgf / cm ² ).

Comparative Example 2 In Example 1, without performing the fluorination treatment after filling with carbon,
Only carbon was used as the lubricant. When the wear coefficient was measured in the same manner as in Example 1, it was 2.7 × 10 ⁻⁴ mm / km) kgf / cm ² ).

Comparative Example 3 2 parts by weight of polyvinyl alcohol, 1 part by weight of polyethylene glycol, 0.5 part by weight of stearic acid and 100 parts by weight of water were mixed with 100 parts by weight of α-alumina powder having an average particle size of 0.4 μm and spray dried.

Collect an appropriate amount of this dried product and use a metal stamping die to obtain 3.0t / c
Molding was carried out at a pressure of m ² to obtain a green molded body having a diameter of 50 mm, a thickness of 20 mm and a density of 2.6 g / cm ³ .

The green compact was inserted into an alumina crucible and fired at a temperature of 1450 ° C. for 1 hour.

The obtained porous body has an average crystal grain size of about 8.5 μm, an average pore size of 3.2 μm, and is bonded in a three-dimensional mesh structure. The density is 3.2 g / cm ³ , and the average bending strength is 28.1 kgf / mm. ^{Was 2} .

After processing this porous body into a ring shape with an outer diameter of 30 mm, an inner diameter of 15 mm and a thickness of 5 mm, it is dipped in an aqueous solution containing 40% by weight of boron nitride powder of 0.05 μm and 5% by weight of water glass, and vacuumed. Pressure impregnation was performed. It was then dried and heated to 500 ° C. The filling rate of the boron nitride in the pores in the porous body is
It was 40% by weight.

In the dry sliding test of this Al ₂ O ₃ porous body filled with boron nitride against stainless steel (SUS304), a ring-on-ring method of sliding at a sliding speed of 500 mm / sec was used to apply an end face load of 10 kgf / cm ^2. When loaded, the wear coefficient was 4.7 × 10
^{It was -4} mm / km (kgf / cm ² ), and it was confirmed that it had extremely excellent sliding characteristics.

Comparative Example 4 The same as Comparative Example 3, except that the ceramic powder shown in Table 1 was used in place of the α-type alumina powder, and the porous ceramic obtained by sintering was used in the same manner as in Comparative Example 3 for boron nitride. Table 1 summarizes the results of the sliding test which was filled with

(Effects of the Invention) As described in detail above, according to the present invention, at least one sliding surface portion of the fixed valve body (13) or the movable valve body (14) is provided with open pores of a three-dimensional mesh structure. It is characterized in that it is formed by a ceramics porous body that has it, and that the open pores are filled with carbon fluoride, whereby the fixed valve body (13) and the moving valve body (14) are always in sliding contact with each other. Even in the state, it is possible to provide a valve that can always perform the communication / shutoff operation by the operation lever in a light and stable state.

Furthermore, as can be understood from the examples and comparative examples, carbon fluoride can reduce the wear coefficient to less than 1/2 as compared with the case where carbon or BN is used as the lubricant, and the self-lubricating property of ceramics. Can be significantly improved.

In addition, in the valve thus formed, not only the operation by the operation lever can be performed lightly over a long period of time, but also the fixed valve body (13) and the movable valve body (14) are brought into close contact with each other. The movements are maintained for a long time without any fluid leakage.

Of course, the above is the same for all types of valves configured to open or close the passage of a liquid other than water or hot water, for example, a liquid such as oil, or a fluid such as a gas such as propane gas. . Further, in applying the present invention, as its material, Al ₂ O ₃ , SiO ₂ , ZrO ₂ , SiC,
TiC, TaC, B ₄ C, WC, Cr ₃ C ₂ , Si ₃ N ₄ , BN, TiN, ZrB ₂ , sialon, TiO ₂ , AlN, TiB ₂ , CrB ₂ , or any of these compounds It can be freely selected from those mainly containing one kind or two or more kinds.

In addition, the fixed valve body (13) or the movable valve body (14) is formed as a whole as described above, and at least the fixed valve body (13) or the movable valve body (14) slides with respect to each other. Similar effects can be obtained even when only the surface portion to be formed is formed and implemented as described above.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a hot and cold water mixing valve according to an embodiment of the present invention, FIG. 2 is a vertical sectional view showing a relationship between a fixed valve body and a moving valve body, and FIG. It is a see-through plan view seen from above. 4 to 9 show an example in which the present invention is applied to a single faucet, and FIG. 4 is a vertical sectional view of the single faucet, and FIG.
FIG. 6 is a perspective view of a fixed valve body and a movable valve body, FIGS. 6 and 7 are plan views showing the relationship between the fixed valve body and the movable valve body, and FIG. 8 is a further embodiment of the movable valve body. FIG. 9 is a plan view showing the relationship between the fixed valve body and the movable valve body in this case. Explanation of symbols 10 …… Hot and cold water mixing valve, 11 …… Valve body, 13 …… Fixed valve body, 14 …… Moving valve body, 17 …… Operating lever, 18 …… Faucet.

Claims (3)

[Claims] 1. An open porosity of 5 at least in the sliding contact surface portion.
A valve element for a bubble, comprising a porous ceramic body having a volume ratio of ˜55% by volume and an average pore size of 0.1 to 100 μm, and having open pores of the porous ceramic body filled with carbon fluoride. 2. The valve body for a valve according to claim 1, wherein the filling amount of the carbon fluoride is at least 10% by volume of the pore volume of the ceramic porous body. 3. The porous ceramic body is made of Al ₂ O ₃ or SiO _2.
2 , ZrO ₂ , cordierite, mullite, SiC, TiC, TaC,
B ₄ C, WC, Cr ₃ C ₂ , Si ₃ N ₄ , BN, TiN, AlN, TiB ₂ , ZrB ₂ , C
The valve body for a valve according to any one of claims 1 and 2, which mainly contains rB ₂ , sialon, TiO ₂ , or any one or more selected from these compounds.