JPH0641021Y2 - Control valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a control valve in which a valve body and a valve seat are made of ceramics.

[Conventional technology]

Ceramics such as alumina, zirconia, silicon nitride, and silicon carbide are known as materials having excellent durability against high temperature, wear, corrosion, etc., and such ceramics are used as valve bodies and valves for control valves. It has come to be used as a seat.

For example, in the conventional valve shown in FIGS. 8 and 9, the valve bodies 80 and 90 and the valve seats 81 and 91 are both made of ceramics.

[Problems to be solved by the device]

However, ceramics has a problem of brittleness, and there is a concern that the ceramic may be damaged due to an impact when the valve body comes into contact with the valve seat, an increase in compression load due to thermal deformation, or the like.

In order to avoid this, conventionally, a means has been adopted such that the valve body and the valve seat do not come into close contact with each other even when the valve is closed. However, in the case of such a configuration, a slight leakage flow of the fluid occurs, that is, the closing property is sacrificed, so that there is a problem that the range of use is limited.

The present invention has been made based on the above circumstances, and its purpose is to enable complete closure while using a ceramic valve body and valve seat, and to prevent damage and improve heat resistance and durability. It is intended to provide an excellent control valve.

[Means for Solving the Problems]

According to the present invention, a ceramic valve seat is slidably inserted into a valve box, and a recess is formed to guide the slide when the valve seat is pushed by the ceramic valve body. An elastically deformable metal O-ring that presses and urges the valve seat in the direction of the valve element is provided between the end surface of the seat and the valve box, and the valve seat exceeds the elastic return range of the metal O-ring. Is provided with a restricting member for restricting sliding in the direction of the valve body.

[Action]

Since the present invention is configured as described above, when the valve body collides with the valve seat, the valve seat is displaced while being guided by the concave portion against the biasing force of the metal O-ring, so that the impact is mitigated. To be done. Further, even when the valve body and the valve seat are pressed against each other due to a temperature change or the like, the metal O-ring is elastically deformed and the valve seat is guided and displaced in the recess, so that the stress is relieved. Therefore, the ceramic valve body and the valve seat are prevented from being damaged, and the valve body and the valve seat can always be kept in close contact with each other in the closed state, so that the completely closed state can be maintained. Moreover, since the metal O-ring has excellent heat resistance, the heat resistance of the ceramic valve body and valve seat can be effectively utilized, and a control valve having excellent heat resistance can be provided.

〔Example〕

 Hereinafter, the present invention will be described based on an embodiment shown in the drawings.

1 and 2, reference numeral 1 is a valve box, and the valve box 1 includes a valve box body 2 and a lid 3. An inflow passage 4 and an outflow passage 5 are formed in the valve box body 2, and in this embodiment, a support member 7 for partitioning the inflow passage 4 and the outflow passage 5 is screwed into the valve box body 2. It is fixed by means. A valve hole 16 that connects the inflow passage 4 and the outflow passage 5 is formed in the support member 7. A recess 8 is formed in the support member 7 at the end of the valve hole 16 and surrounds the valve hole 16, and the recess 8 accommodates the valve seat 6.

The valve seat 6 is made of an appropriate ceramic and is fitted in the recess 8 so as to be slidable in the axial direction, that is, in the direction of the valve body 12. The valve seat 6 is prevented from coming out of the recess 8 by a restricting member 10, and the restricting member 10 is fixed by the bolt 9 to the supporting member 7 described above.
Installed on. Therefore, the sliding range of the valve seat 6 is regulated by the bottom surface 14 of the recess 8 and the regulating member 10. When the valve seat 6 contacts the regulating member 10, the valve seat 6
A gap 15 (see FIG. 4, FIG. 6 and FIG. 7) having a predetermined size is formed between the end face of the and the bottom face 14 of the recess 8. Then, the end surfaces of the valve seat 6 and the bottom surface of the recessed portion 8
An elastic seal member composed of a metal O-ring 13 is provided between the elastic seal member 14 and 14. The metal O-ring 13 is fitted in, for example, an O-ring groove formed on the bottom surface 14 of the recess 8 and has a height protruding from the bottom surface 14 between the valve seat 6 and the bottom surface 14 in a free state. It is set to be larger than the gap 15 formed. That is, in other words, the valve seat 6 and the bottom surface
The size of the gap 15 formed between the metal O ring 13 and
It is set to be within the elastic recovery range of. Therefore, the valve seat 6 is pushed by the metal O-ring 13,
When the valve seat 12 is not in contact with the valve seat 6 (see FIGS. 3 and 4), the valve seat 6 is pressed against the restricting member 10 and further movement is restricted.

A valve shaft 11 is axially displaceably supported by the lid 3 with respect to the valve seat 6, and a valve body 12 made of a suitable ceramic is attached to an end of the valve shaft 11. Has been. The valve body 12 closes the valve hole 16 by coming into contact with the valve seat 6.

In the control valve having the above-mentioned structure, in the open state, as shown in FIG. 3, the valve body 12 is separated from the valve seat 6, so that the elastic return force of the metal O-ring 13 causes the valve seat to move. 6
Is pressed against the regulating member 10. In this case, as shown in FIG. 4, the gap 15 between the valve seat 6 and the bottom surface 14 is relatively wide, but since this gap 15 is sealed by the metal O-ring 13, this gap 15 is There is no worry of fluid leaking from 15.

Further, when the valve body 12 is brought into contact with the valve seat 6 to be closed, as shown in FIG. 5, the valve seat 6 pushed by the valve body 12 pushes the metal O-ring 13 to push the metal. O-ring
Since 13 is elastically deformed, the valve seat 6 is slidably displaced along the recess 8. Therefore, the impact when the valve body 12 abuts on the valve seat 6 is absorbed and alleviated, and the ceramic valve body 12 and the valve seat 6 are prevented from being damaged.

At this time, as shown in FIG. 6, the valve seat 6 and the bottom surface are
Although the gap 15 between it and 14 becomes narrower, the metal O-ring 13 exists in this gap 15 so that it does not become zero, and this gap 15 is reliably sealed by the metal O-ring 13. Therefore, there is no concern about leakage of fluid.

Further, even if the valve body 12, the valve seat 6 or other surrounding members are thermally expanded or contracted due to a temperature change or the like, as shown in FIG.
Since the valve seat 6 is axially displaced relative to the support member 7 and the metal O-ring 13 provided between the valve seat 6 and the bottom surface 14 is deformed, the ceramic valve body 12 or valve seat No stress is generated in 6 due to an excessive compressive load, etc. Therefore, the ceramic valve body 12 and valve seat 6 are not damaged. Moreover, the gap 15 between the valve seat 6 and the bottom surface 14 can be reliably sealed by the metal O-ring 13.

According to the control valve having the above-described configuration, when the valve body 12 collides with the valve seat 6, the valve seat 6 deforms the metal O-ring 13 and the recess 8 is formed.
Even if the valve element 12 and the valve seat 6 are pressed against each other due to temperature deformation of each part, the valve element 12 and valve seat 6 are displaced in the same direction while being guided by the valve. Seat 6
Can escape along with the elastic deformation of the metal O-ring 13, so that the stress can be relieved.

Therefore, it is possible to prevent problems such as damage to the valve body 12 and the valve seat 6 and damage to the mutual contact surfaces, and it is possible to sufficiently ensure the durability of the ceramic valve body 12 and the valve seat 6. It is possible to maintain a complete occlusion function.

When the valve body 12 is separated from the valve seat 6, the valve seat 6
Since the position is regulated by hitting the regulating member 10, the position when the valve body 12 comes in contact with and separates from the valve seat 6 can be kept constant, and the valve closing and valve opening characteristics do not vary. Since the size of the gap 15 in this case is set by the regulating member 10, it can be set within the elastic return range of the metal O-ring 13, and a reliable seal can be maintained regardless of the position of the valve seat 6.

Further, since the metal O-ring is used as the elastic seal member, the structure is simple and inexpensive, and the metal O-ring 13 itself has excellent heat resistance. Therefore, the metal O-ring 13 cooperates with the ceramic valve body 12 and the valve seat 6. Thus, a control valve having excellent heat resistance can be provided.

Further, since the valve seat 6 is slidably guided by the recess 8 formed in the support member 7, the movement of the valve seat 6 is stable, and the shock and stress relaxation operations can be stably performed.

[Effect of device]

As described above, according to the present invention, even if the valve body and the valve seat are made of ceramics, the impact and the stress are relieved, so that the valve body and the valve seat can be completely closed without damaging them. Moreover, since the heat-resistant metal O-ring is used, it is possible to provide a control valve in which the heat resistance and durability of ceramics are fully utilized.

[Brief description of drawings]

FIG. 1 is a sectional view of a control valve showing an embodiment of the present invention, and FIG.
The figure is a partial sectional view showing the vicinity of the valve seat in the same example in an enlarged manner.
FIGS. 3 and 4 are explanatory views showing a valve open state, FIGS. 5 and 6 are explanatory views showing a valve closed state, and FIG. 7 is an explanatory view showing a state when displaced due to temperature change, 8 and 9 are sectional views of a control valve showing different conventional examples. 1 ... Valve box, 2 ... Valve box main body, 3 ... Lid body, 4 ... Inflow path, 5 ...
Outflow passage, 6 ... Valve seat, 7 ... Support member, 8 ... Recessed portion, 10 ... Regulator member, 12 ... Valve body, 13 ... Metal O-ring, 14 ... Bottom surface, 15 ...
Gap, 16 ... valve hole.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Shiroro Fukase 72-1 Nakayama, Sendai City, Miyagi Prefecture Tohoku Denryoku Co., Ltd. (72) Teruo Onozuka 7-2 Nakayama, Sendai City, Miyagi Prefecture No. 1 Tohoku Electric Power Co., Inc. Research Institute (72) Inventor Norio Kanaya 1-12-1 Tsutsumicho, Sendai City, Miyagi Prefecture Motoyama Plant (72) Inventor Politics Takahashi 1-chome Tsutsumicho, Sendai City, Miyagi Prefecture No. 12 No. 1 inside the Motoyama Seisakusho Co., Ltd. (56) Reference JP 54-82722 (JP, A) JP 59-147168 (JP, A) JP 60-11607 (JP, A) Actual public 55-26610 (JP, Y2)

Claims (1)

[Scope of utility model registration request] 1. A ceramic valve seat is provided in a valve hole formed in a valve box, and a ceramic valve body for opening and closing the valve hole is provided in the valve box so as to come into contact with and separate from the valve seat. In the control valve provided, the valve seat is slidably inserted into the valve box, and a recess is formed to guide the valve seat when the valve seat is pushed by the valve body. An elastically deformable metal O-ring that presses and urges the valve seat toward the valve body is provided between the end surface of the valve seat, and the valve box has the valve seat with an elastic return range of the metal O-ring. A regulating valve provided with a regulating member for regulating the displacement in the direction of the valve body beyond the valve.