JPS5934770Y2 - Valve stem end sealing device for chi-shaped valves - Google Patents

Description

[Detailed Description of the Invention] (1) Purpose of the Invention (Field of Industrial Application) This invention relates to a butterfly valve, and particularly to a sealing mechanism at the end of the valve shaft.

(Prior Art and Issues to be Solved) A butterfly valve usually has a hollow cylindrical valve body with a through hole at diametrically opposed positions, into which the valve stem is rotatably inserted.
The valve plate is fixed to the inside part of the valve body, and one end of the valve shaft is extended to the outside of the valve, and this part is used to rotate the valve shaft to open and close the valve plate. It is composed of:

At this time, as shown in FIG. 1, the other end of the valve shaft is inserted into the through hole formed in the valve body 4 and the boss part 5 integrated therewith, and does not protrude outside the valve. A lid is provided on the lower surface of the boss portion 5 to prevent liquid leakage from inside the valve, entry of foreign matter from outside the valve, rusting of the valve stem or boss portion, etc., and this is secured with bolts or other suitable means. It is common to fix it or attach it with a screw stopper.

However, since this part is originally not directly related to the performance of the valve, many parts are used to seal this part, and the boss part of the valve body and the end of the valve shaft need to be repaired without much effort. It is undesirable to process the material over a long period of time from the viewpoint of cost.

From this point of view, this proposal uses extremely inexpensive members to obtain the same sealing effect as in the conventional case, and also to prevent fluid pressure in the valve from increasing and leaking along the valve shaft. At a given pressure, the member ruptures due to internal pressure to release this pressure, and the ruptured part also has a certain degree of sealing effect as the internal pressure decreases to prevent inconveniences such as foreign matter from entering or rusting. It is an object of the present invention to provide a valve stem-to-valve shaft sealing device that can perform the following functions.

(2) Structure of the invention (techniques to solve the problem and its effects) In order to achieve the above purpose, in this invention, a cylindrical part is attached to the end of the valve shaft, which is supported by the valve body, from the outside of the valve. A sealing member consisting of a plate-shaped portion integrally formed with a sealing member is disposed, and a thin arc-shaped portion with a partially chipped portion is formed in the plate-shaped portion.

With this structure, when the fluid pressure inside the pipe expands along the outer periphery of the valve shaft, the thin wall portion can be torn open to release the fluid pressure, and the torn part can be prevented from falling off. Its own elasticity tends to take a position that closes the torn part, temporarily maintaining a loosely sealed state, preventing the intrusion of foreign matter, and making it possible to easily maintain the assembly. It is something.

(Description of Embodiments) An embodiment of the present invention will be described with reference to the attached drawings. As shown in FIGS. 2A and 2B, the sealing member according to the present invention has the following features:
A cylindrical portion 1 into which the end of the valve stem is inserted and a dish-shaped portion 2 that abuts the lower surface of the valve body boss portion 5 are integrally molded from a suitable elastic material such as relatively flexible and highly elastic rubber or plastic. As is clear from FIG. 2B, a C-shaped groove 3 is formed on the lower surface of the dish.

Note that the outer peripheral surface of the cylindrical portion 1 is formed with a large number of unevenness or protrusions 11 for good frictional engagement with the inner surface of the through hole of the valve body, and the peripheral edge of the dish-shaped portion 2 is formed with a thin wall portion. 21 so that this thin wall portion comes into pressure contact with the lower surface of the valve body boss portion 5 when mounted on the valve body.

The sealing member 10 configured in this way is fitted and fixed to the end of the valve shaft 6 as shown in FIG.

By appropriately selecting the inner diameter of the cylindrical portion 1, the diameter of the valve stem, the outer diameter of the cylindrical portion 1, the inner diameter of the through hole of the valve body, and the elasticity of the material of the sealing member, the valve can be adjusted by installing the sealing member. It is well understood that the inside and outside of the valve can be reliably shut off at the shaft end.

In a valve equipped with a sealing member, when the pressure inside the valve is high and leaks to the end of the valve, the C-shaped groove 3 of the dish-shaped portion 2 of the sealing member forms a groove due to the magnitude of the internal pressure. The thin walled part will split open and release the internal pressure.

After the internal pressure is released and reduced, the torn area will
Due to the elasticity of the part connected to the other parts of the dish, it tends to return to its original position, so it is close to the position before rupture and close to the closed state, so even after that, it is difficult to prevent external damage. It has the effect of preventing foreign matter from entering.

(3) Effects of the invention Once the sealing member is installed, even if it ruptures due to internal pressure during subsequent inspection and repair, it will not fall off from the valve body and will retain its sealing effect to some extent. This is convenient for maintaining the equipment.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway end view of a butterfly valve equipped with a sealing member according to the present invention, and FIGS. 2A and 2B are a sectional view and a bottom view of the sealing member according to the present invention. In the figure, code 10... Sealing member, 1...
Cylindrical part, 2...Dish-shaped part, 3...Groove, 4
... Valve body, 5 ... Boss part, 6 ...
...Valve shaft.

Claims (1)

[Scope of utility model registration request] At least one end of a valve stem of a butterfly-shaped valve in which both ends of a valve stem, to which a valve plate disposed within the valve body is fixed, are supported in through holes formed at diametrically opposed positions in the valve body. It consists of a cylindrical part that is inserted into the end of the valve shaft and a dish-shaped part that comes into contact with the outer surface of the valve body, and a hole of approximately C is formed on the outer surface of the dish-shaped part at a position corresponding to the through hole. A valve shaft end sealing device for a butterfly-shaped valve, which is equipped with a sealing member formed of a letter-shaped thin wall portion.