JPH061961U - Control valve - Google Patents

Abstract

(57) [Summary] [Object] The present invention relates to a bellows seal control valve or a diaphragm seal control valve having a structure in which fluid does not flow out of the valve even if the seal part creeps due to long-term fluid pressure fluctuations and temperature changes. The purpose of the invention is to provide a control valve which is extremely compact. A partition wall 2 provided between an inlet flow path 3 and an outlet flow path 4 inside the main body 1 and having a curved flow direction, and an opening provided in the partition wall 2 for communicating the inlet flow path 3 with the outlet flow path 4 And a closing valve 7 provided with a control valve 8 projecting from the opening 5 coaxially with the opening 5. The closing valve 7 is integrated with a diaphragm or bellows-shaped diaphragm 9. Of the main body fixing portion 10 at the peripheral edge of the diaphragm or bellows-like diaphragm 9 in a control valve whose bottom surface is abutted against the valve seat portion 6 formed at the peripheral edge of the opening. Is integrally provided, and the main body fixing portion 1
0 is sandwiched between the main body 1 and the bonnet 12 via the elastic body 11.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a control valve used in a fluid transportation pipe, and more particularly to a control valve having improved sealing performance of a diaphragm seal control valve or a bellows seal control valve.

[0002]

[Prior art]

 In the conventional diaphragm seal control valve or bellows seal control valve, as shown in FIG. 5, the locking protrusion 21 of the diaphragm or bellows is fitted into the fitting groove 22 of the bonnet 23, and the bonnet 23 and the main body 1 are joined together. By sandwiching and fixing, the fluid is prevented from leaking to the outside of the valve body.

[0003]

[Problems to be solved by the device]

 However, the sealing method with the above configuration has a problem in that the seal portion creeps and fluid leakage occurs due to pressure changes and temperature changes of the fluid over a long period of time. This tendency is remarkable especially when the diaphragm or bellows is made of a fluororesin (PTFE, PFA, etc.) which is preferably used as the material.

The present invention has been made to solve the above-mentioned problems of the prior art. The purpose of the present invention is to prevent the seal portion from creeping due to fluid pressure fluctuations or temperature changes. It is to provide a control valve having a structure that does not cause liquid leakage.

[0005]

[Means for Solving the Problems]

 The control valve of the present invention for solving the above-mentioned problems includes a partition wall provided between an inlet flow path and an outlet flow path inside the main body to bend the flow direction, and the inlet flow path provided in the partition wall. An opening for communicating the passage with the outlet passage; and a closing valve provided with a control valve projecting coaxially with the opening and capable of being inserted into the opening. The closing valve has a diaphragm or bellows shape. Of the diaphragm or the bellows-shaped diaphragm, the lower end surface of which can be brought into contact with the valve seat formed on the peripheral edge of the opening. The main body fixing portion is integrally provided, and the main body fixing portion is sandwiched between the main body and the bonnet via an elastic body.

The material of the control valve of the present invention may be metal or plastic and is not particularly limited. Further, the material of the diaphragm or the bellows-like membrane is not particularly limited, but a fluororesin (for example, PTFE, PFA, ECTFE, etc.) is particularly preferable.

[0007]

[Action]

 In the control valve of the present invention having the above-mentioned configuration, in the valve open state, the fluid passes from the inlet flow passage through the opening, passes through the closing valve, the bellows-shaped diaphragm, and the valve chamber formed by the main body to the outlet flow passage. And spill. At this time, the fluid that has reached the valve chamber tends to flow out of the valve due to the action of the pressure, but the main body fixing part that is integrally provided on the peripheral edge of the bellows diaphragm is clamped and fixed by the main body and the bonnet. Therefore, the outflow of fluid is prevented.

Further, even if the main body fixing portion creeps due to pressure fluctuations or temperature changes of the fluid over a long period of time, since the main body fixing portion is pressed by the elastic body, the action of the elastic body causes the main body fixing portion 10 to move. The clearance between the lower surface of the and the main body abutting part is not expanded, and the sealing effect can always be maintained.

Further, when the closing valve integrally provided on the bellows-shaped diaphragm is moved up and down by the driving force from the outside, the control valve protruding from the closing valve also follows the up and down movement. Move. Along with this, the gap between the opening and the control valve is adjusted, so that the present control valve can control the flow rate of the fluid flowing from the inlet passage to the outlet passage.

Further, when the closing valve is moved downward by the driving force from the outside, it comes into contact with the main body valve seat portion and is further pressed, so that the flow of the fluid is stopped here and the valve is completely closed.

[0011]

【Example】

 FIG. 1 is a longitudinal cross-sectional view of a main part showing an intermediate opening state of a bellows seal control valve according to an embodiment of the present invention. In the figure, reference numeral 1 denotes a main body, which is configured so that an inlet flow passage 3 and an outlet flow passage 4 are partitioned by a partition wall 2 provided inside and the flow passages 3 and 4 are curved. . An opening 5 is provided in the partition wall 2 and connects the inlet channel 3 and the outlet channel 4. Reference numeral 6 is an annular valve seat integrally provided around the partition wall 2, that is, the opening 5. Further, a valve chamber 16 is provided in the main body 1 in a direction perpendicular to the flow axis of the flow paths 3 and 4.

Reference numeral 9 is a PTFE bellows-like diaphragm, which is integrally provided with a stop valve 7 at the lower end and a main body fixing portion 10 at the upper peripheral edge. A valve shaft 13, which has the same axis as the axis of the opening 5 and which is supported by the opening 14 of the tubular bonnet 12, is screwed and fixed to the central portion above the shutoff valve 7. Further, a control valve 8 is provided at the lower end of the shutoff valve 7 so as to be coaxial with the shutoff valve 7 and have a diameter reduced downward so that the control valve 8 can be inserted into the opening 5. In this embodiment, the control valve 8 is made of the same material as that of the shutoff valve 7, but the present invention is not limited to this, and the control valve 8 made of a different material is fixed to the shutoff valve 7. May be.

The body fixing portion 10 is pressed from above by a tubular bonnet 12. Therefore, the main body fixing portion 10 is sandwiched and fixed by the main body 1 and the bonnet 12, and the lower surface 10-a of the main body fixing portion 10 is tightly fixed to the flat portion 1-a provided on the upper portion of the main body 1.

At the center of the cylindrical bonnet 12, an opening 14 is provided which slidably supports the valve shaft 13. Further, an annular groove 15 is provided at a position corresponding to the flat portion 1-a in the lower end portion of the bonnet 12, and an O-ring 11 is attached to it.

The operation of the bellows seal control valve of this embodiment having the above structure is as follows. In FIG. 1, when a fluid is flown through the valve, the fluid passes through the inlet passage 3, the opening 5, and the valve chamber 16 and flows out to the outlet passage 4. At this time, the fluid that reaches the valve chamber 16 is removed. Due to the action of the pressure, the pressure tends to pass through the clearance between the lower surface 10-a of the main body fixing portion 10 on the peripheral edge of the bellows-shaped diaphragm and the flat portion 1-a provided on the upper portion of the main body 1 to flow out of the valve. However, since the main body fixing portion 10 is closely clamped and fixed to the flat portion 1-a of the main body 1 by the bonnet 12, the outflow of fluid to the outside of the valve is blocked. Further, even if the main body fixing portion 10 and the flat portion 1-a creep or distort due to long-term fluctuations in fluid pressure and temperature, the main body fixing portion 10 is flattened by the elastic action of the O-ring 11. Since it is constantly pressed by the portion 1-a, the clearance between the lower surface 10-a and the flat portion 1-a does not increase, and the fluid is prevented from flowing out of the valve.

By using the O-ring as the elastic member as in this embodiment, it is possible to most effectively achieve the purpose of intensively pressing the main body fixing portion 10 against the main body flat portion 1-a, and at the same time, the elastic member. Since the creep of itself can be suppressed to a minimum, it can also have the synergistic effect of allowing the elastic action for a long period of time. In that sense, it is much more effective to use an O-ring as the elastic member than to use a commonly used sheet packing having a rectangular cross section.

Next, when the closing valve 7 is moved up and down via the valve shaft 13 by the driving force from the outside, the control valve 8 protruding from the closing valve 7 also moves up and down accordingly. Along with this, the distance between the opening 5 and the control valve 8 is adjusted, so that the present control valve can control the flow rate of the fluid flowing from the inlet passage 3 to the outlet passage 4.

When the stop valve 7 is further moved downward by the driving force from the outside, it finally comes into contact with the valve seat portion 6 and is further pressed. Therefore, the flow path is now completely blocked and the valve is closed. Further, from this state, when the shut-off valve 7 is moved upward through the valve shaft 13 by the opposite action, the valve is opened again. In this way, the valve is opened and closed and the fluid flow rate is controlled.

FIG. 3 is an enlarged vertical cross-sectional view of a main part showing another embodiment of the bellows seal control valve of the present invention. The structure of this embodiment is different from that of the first embodiment in that the flat portion 1-a of the main body is provided with annular protrusions 17 and 18 having a triangular cross section, and that the elastic member is a seat instead of the O-ring. A packing 19 is used, and the sheet packing 19 is configured to be able to press the peripheral edge of the bellows-shaped diaphragm, that is, the upper surface of the main body fixing portion 10 over a wide range, and other configurations are the same as those in the first embodiment. is there.

According to the bellows seal control valve of the present embodiment configured as described above, the lower surface 10-a of the main body fixing portion 10 is pressed by the annular projections 17 and 18, so that the fluid can be exposed to the outside of the valve. The spill is stopped here. Further, since the contact area between the annular projections 17 and 18 and the lower surface 10-a of the main body fixing portion 10 is extremely small, the sealing effect is extremely large. Further, even if the main body fixing portion 10 and the flat portion 1-a of the main body 1 creep due to long-term fluctuations in the fluid pressure and temperature, the top surface of the main body fixing portion 10 is covered with the annular packing 17 and the sheet packing 19. Since it is pressed by 18, the elastic action of the sheet packing 19 does not increase the clearance between the main body fixing portion 10 and the main body flat portion 1-a, and the sealing action is maintained.

In the case of this embodiment, since the annular protrusions 17 and 18 are pressed against the main body fixing portion 10 at two places, even if the annular protrusions 18 or 17 are damaged for some reason, the second annular protrusion 17 Alternatively, there is a double sealing effect such that 18 acts to prevent the fluid from flowing out of the valve. The other operations are the same as those of the first embodiment of the present invention, so the description thereof will be omitted.

Needless to say, the annular projections 17 and 18 described in the present embodiment bring about a greater effect when applied to the first embodiment of the present invention.

FIG. 4 is a vertical cross-sectional view of the essential parts showing the intermediate opening state of the diaphragm seal control valve according to another embodiment of the present invention. The construction and operation are the same as those of the bellows seal control valve, and therefore will be omitted.

[0024]

[Effect of device]

 By using the bellows seal control valve or diaphragm seal control valve of the present invention having the above-described structure, even if the seal portion creeps due to long-term fluctuations in fluid pressure and temperature, liquid leakage to the outside of the valve This enables extremely safe fluid control with no risk. Further, since this effect is achieved by an extremely simple structure, the valve device can be made compact and at the same time an effect such as being extremely inexpensive can be obtained.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of an essential part showing an embodiment of a bellows seal control valve of the present invention.

FIG. 2 is an enlarged vertical sectional view of an essential part showing a seal portion in FIG.

FIG. 3 is an enlarged longitudinal sectional view of a main part showing another embodiment of the bellows seal control valve of the present invention.

FIG. 4 is a longitudinal sectional view of an essential part showing an embodiment of the diaphragm seal control valve of the present invention.

FIG. 5 is a vertical cross-sectional view of a main part of a conventional bellows seal control valve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Main body 2 ... Partition wall 3 ... Inlet flow passage 4 ... Outlet flow passage 5 ... Opening portion 6 ... Valve seat portion 7 ... Stop valve 8 ... Control valve 9 ... Bellows-like diaphragm 10 ... Main body fixing portion 11 ... O-ring 12 ... Bonnet 13 ... Valve shaft 16 ... Valve chamber 17,18 ... Locking projection 19 ... Seat packing 20 ... Diaphragm

Claims (2)

[Scope of utility model registration request] 1. A partition wall provided between an inlet flow channel and an outlet flow channel inside the main body, the flow channel being curved, and an opening provided in the partition wall for communicating the inlet flow channel and the outlet flow channel. A closing valve provided with a control valve projecting from the opening coaxially with the opening, the closing valve being provided integrally with a diaphragm or a bellows-shaped diaphragm and having a lower end surface In a control valve capable of contacting a valve seat portion formed on the peripheral edge of the opening, a main body fixing portion is integrally provided on the peripheral edge of the diaphragm or bellows-like diaphragm, and the main body fixing portion is the main body. A control valve characterized by being sandwiched by an elastic body and a bonnet. 2. The control valve according to claim 1, wherein the elastic body is O.
A control valve characterized in that it is a ring.