JP2001132855A - Butterfly valve and its sealing member fitting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a butterfly valve and its sealing member fitting method environmentally harmless using a small quantity of rubber, allowing easy and positive fitting and fixing of a sealing member. SOLUTION: The sealing member 13 is inserted in a sealing member fitting groove 15 of dovetail groove shape from the cross-sectional view, and its inner peripheral part is bifurcated 13a, 13b from the cross-sectional view. A wedge member 16 inserted between the bifurcated parts 13a, 13b to widen them is fitted to a bottom face 15a. A sealing member fitting method comprises a wedge member fitting process of insert-fitting the wedge member 16, an inserting process of inserting the sealing member 13 in the sealing member fitting groove 15, and a widening process of inserting the sealing member 13 in the sealing member fitting groove 15 and widening a space between the bifurcated parts 13a, 13b by the wedge member 16 to fill out inside the sealing member fitting groove 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a butterfly valve connected to a pipeline such as a water channel for controlling the pressure and flow rate of a fluid.

[0002]

2. Description of the Related Art In various fields, butterfly valves are widely used for controlling the pressure and flow rate of a fluid. The general structure of a conventional butterfly valve of this type will be described below with reference to FIG. The butterfly valve includes a valve box 1 in which a cylindrical flow path through which a fluid flows is formed, a valve stem 2 vertically and rotatably supported in the flow path in the flow path, A valve body 3 fixed to the rod 2 and rotating to open and close a flow path, a valve seat 4 whose outer peripheral edge is in close contact with the valve body 3 in a closed state, and a rotation for rotating the valve rod 2 And a driving force transmission mechanism 5 (reduction gear) for transmitting driving force.

The valve seat 4 is formed by processing a rubber material into a thin cylindrical shape, and has the same length as the entire flow path in the valve box 1 so as to cover the entire inner wall surface 1a of the valve box 1. are doing. In addition, the thickness of the valve body 3 is deformed to some extent when the valve body 3 comes into close contact with the valve body 3 to obtain a sealing property, and in consideration of wear and the like,
It has a predetermined thickness. When the valve seat 4 is attached to the butterfly valve, the valve seat 4 is attached to the valve box 1 so that there is no gap between the outer peripheral surface 4a of the valve seat 4 and the inner wall surface 1a.
The fixing method includes a method in which an adhesive is applied between the outer peripheral surface 4a and the inner wall surface 1a, and vulcanization is performed with the valve seat 4 inserted.

[0004]

The conventional butterfly valve described above has the following problems. That is, rubber is preferably used as the material of the valve seat 4, and is generally used by lining over the entire length of the flow path in the valve box 1 as described above. When it is necessary to replace the valve seat 4, it is necessary to remove the entire valve seat 4 from the valve box 1. Therefore, considering the disposal of the removed valve seat 4, if the amount of rubber used is large, The problem is that it is not environmentally preferable. Another problem is that when the process of attaching the valve seat 4 to the butterfly valve is considered, such a long and large valve seat 4 is required.
The operation of correctly inserting into the valve box 1 and fixing it uniformly and securely at all surface contact portions by vulcanization is troublesome, and there is a problem that it is difficult in some cases.

The present invention has been made in view of the above circumstances, and has the following objects. That is, the present invention provides a butterfly valve which uses a small amount of rubber, is environmentally friendly, and can easily and reliably mount and fix a seal member for sealing between a valve body and an inner wall surface of a valve box, and a method of mounting the seal member. Aim.

[0006]

Means for Solving the Problems The butterfly valve of the present invention and the method of attaching a seal member thereof employ the following means to solve the above-mentioned problems. In other words, the butterfly valve according to the first aspect is provided with a valve box having a cylindrical flow path through which a fluid flows, and is rotatably supported in the flow path in the direction perpendicular to the inflow direction of the fluid. In a butterfly valve including a valve stem and a valve body that is fixed to the valve stem and rotates to open and close the flow path, an outer peripheral edge of the valve body is formed by opening along the outer peripheral edge. A sealing member mounting groove having a dovetail groove shape in cross section is formed, and the inner peripheral portion facing the bottom surface of the sealing member mounting groove is bifurcated in the sealing member mounting groove so as to expand toward the bottom surface. A sealing member, which is a branched elastic body, is inserted, and a wedge member is provided on the bottom surface of the sealing member mounting groove to be inserted between the forked branches and to expand them in a direction to separate them from each other. When the valve element closes the flow path, the member Characterized in that it is a close possible to the surface.

According to the butterfly valve of the first aspect, after the wedge member is inserted into and attached to the bottom surface of the valve member in the seal member mounting groove, the inner periphery of the seal member is brought close to the two branches. By pressing this part into the seal member mounting groove, this is inserted into the seal member mounting groove, and further, the seal member is inserted toward the bottom surface of the seal member mounting groove so that the wedge member in the seal member mounting groove enters between the forked branches. The fork is expanded by the wedge member, and the inner peripheral portion of the seal member is thickened in the thickness direction so as to match the shape of the seal member mounting groove, so that the seal member is easily and securely fixed in the seal member mounting groove. . Further, since the sealing member fixed in this way is a small annular body as compared with a conventional large-sized valve seat, when disposing of this for reasons such as life, the amount of disposal is small. I can do it.

[0008] The butterfly valve according to the second aspect is the first aspect.
In the butterfly valve described above, the seal member is a rubber material having a hardness of 45 to 75, and the wedge member is a rubber material having a hardness of 85 to 95 and a hardness higher than that of the seal member. There is a feature.

According to the butterfly valve of the second aspect, the hardness of the seal member is in the range of 45 to 75, and the hardness of the wedge member is in the range of 85 to 95 and higher than the hardness of the seal member. Thus, when the seal member is inserted into the seal member mounting groove of the valve body, the wedge member does not lose the hardness of the seal member and is deformed, so that the wedge member is reliably formed on the inner peripheral portion of the seal member. Can be spread to make it fat.

According to a third aspect of the present invention, in the butterfly valve according to the first or second aspect, an engaging projection is formed on one of the joining surfaces between the wedge member and the seal member. On the other hand, an engagement groove with which the engagement protrusion engages is formed.

According to the butterfly valve of the third aspect, an engagement projection is formed on one of the joining surfaces of the wedge member and the seal member, and the engagement projection is engaged with the other. By forming the groove, when the seal member is inserted and fixed in the seal member mounting groove, the engagement protrusion and the engagement groove are engaged, and the seal member and the wedge member are non-separably coupled. .
Accordingly, the wedge member does not come off between the forked portions formed in the inner peripheral portion of the seal member, so that the inner peripheral portion of the seal member is maintained in a fat state in the seal member mounting groove.

According to a fourth aspect of the present invention, there is provided a butterfly valve.
3. The butterfly valve according to any one of claims 1 to 3, wherein a fitting projection is formed on one of a joining surface between the bottom surface of the sealing member mounting groove and the wedge member, and the fitting projection is formed on the other. It is characterized in that a fitting groove into which the protrusion is fitted is formed.

According to the butterfly valve of the fourth aspect, the wedge member is attached to the bottom surface of the seal member mounting groove so that the fitting protrusion is fitted into the fitting groove, so that the wedge member is attached to the seal member mounting groove. It can be easily and accurately positioned and fixed to the bottom surface of the device.

According to a fifth aspect of the present invention, there is provided a butterfly valve.
4. The butterfly valve according to any one of 1 to 4, wherein a protrusion is formed on the inner peripheral surface of the valve box along a portion where the seal member contacts when the flow path is closed. Features.

According to the fifth aspect of the present invention, when the flow path is closed by the valve body, the projection is caught in the sealing member, and the compressive force generated between the projection and the sealing member is concentrated on the biting portion. Can be done.

According to a sixth aspect of the present invention, there is provided a method for attaching a seal member to a butterfly valve, comprising: a valve box having a cylindrical flow path through which a fluid flows; A valve shaft rotatably supported, a valve body fixed to the valve shaft and rotating to open and close the flow path, and a valve body mounted on an outer peripheral edge of the valve body so that the valve body In a method of attaching the seal member to the valve body of a butterfly valve having a seal member that is in close contact with the inner peripheral surface of the flow path when closed, the butterfly valve is formed so as to open along the outer peripheral edge of the valve body. A wedge member mounting step of mounting a wedge member on a bottom surface in a seal member mounting groove having a dovetail shape in cross section, and a fork so that a cross section viewed in an imaginary plane passing through the ring and its axis is expanded toward the inner periphery. The sealing member, which is a branched elastic body, is pressed so that the forked branch approaches each other. An insertion step of inserting into et the seal member mounting groove, and having a press spread process of thickening by the wedge member in the bifurcated between again press spread the seal member attaching groove.

According to the method of attaching a seal member to a butterfly valve according to the sixth aspect, the insertion step is performed after the wedge member attaching step, and the push-spread step is performed thereafter, whereby the seal member is attached. That is, after inserting and mounting a preformed wedge member on the bottom surface of the valve member in the seal member mounting groove, the inner peripheral portion of the seal member is pressed so that the two branches are brought closer to each other, and then sealed. By inserting the seal member toward the bottom surface of the seal member mounting groove so that the wedge member in the seal member mounting groove enters between the forked branches, the wedge member presses the gap between the forked portions. The seal member is widened in the thickness direction so that the inner peripheral portion of the seal member conforms to the shape of the seal member mounting groove, so that the seal member is easily and reliably fixed in the seal member mounting groove.

The sealing member can be attached by performing a wedge member attaching step and a push-out step after the inserting step. That is, the inner peripheral portion of the seal member is pressed so that the two branches are brought closer to each other, and then the seal member is inserted into the seal member mounting groove. Thereafter, for example, a curable molten resin or the like is injected and cured between the two branches. Thus, a wedge member is formed between the two branches. The wedge member formed in this way pushes the fork between the two branches, and the inner peripheral portion of the seal member is thickened in the thickness direction so as to conform to the shape of the seal member mounting groove. Easily and securely fixed.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. 1 to 7, but it is needless to say that the present invention is not limited to this. . FIG. 1 is a view showing a first embodiment of the butterfly valve of the present invention, in which the left half of the paper is a side outline view and the right half of the paper is a cross-sectional view showing an internal structure. FIG. 2 is a view of the butterfly valve as viewed from the line AA in FIG. 1, and FIG. 3 is a diagram showing a main part of the butterfly valve, and is an enlarged view of a portion B in FIG. It is. FIG.
FIG. 5 is a front view showing a wedge member which is one component of the butterfly valve, and FIG. 5 is a view showing the same wedge member of the butterfly valve, and is an enlarged cross-sectional view taken along line CC of FIG. It is. FIG. 6 is a front view showing a seal member which is one component of the butterfly valve. FIG. 7 is an enlarged cross-sectional view of the same seal member of the butterfly valve taken along line DD in FIG. .

As shown in FIGS. 1 and 2, the butterfly valve according to the present embodiment comprises a valve box 10 having a tubular flow path through which a fluid flows, and a valve box 10 having a fluid flow direction in the flow path. A valve rod 11 vertically and rotatably supported, a valve element 12 fixed to the valve rod 11 and rotating to open and close a flow path;
A sealing member 13 attached to the outer peripheral edge of the valve body 2 to seal the flow path when the valve body 12 is closed, and a driving force transmission mechanism 14 for transmitting a rotational driving force for rotating the valve rod 11
(Reduction gear). In addition, the butterfly valve in these drawings shows a state where the valve body 12 opposes the flow of the fluid and closes the flow path.

As shown in FIG. 3, on the outer peripheral edge of the valve body 12, a seal member mounting groove 15 having a dovetail-shaped cross section is formed along the outer peripheral edge. The sealing member mounting groove 15 is provided in the sealing member mounting groove 15.
The seal member 13, which is an elastic body having two branches 13a and 13b, is inserted and fixed so that an inner peripheral portion facing the bottom surface 15a of the above-mentioned member expands toward the bottom surface 15a. The seal member 13 is annular, and can be in close contact with the inner peripheral surface 10a forming the flow path when the valve body 12 closes the flow path. The fitting groove 15d (described later) formed on the bottom surface 15a of the seal member mounting groove 15 has two branches 13a, 1a.
An annular wedge member 16 which is inserted between the members 3b and spreads in a direction to separate them from each other is fixed.

In the line of sight shown in FIG.
Reference numeral 5 denotes an annular groove having a pair of side surfaces 15b and 15c which approach each other from the bottom surface 15a toward the opening 12a and are parallel to each other near the opening 12a. Further, the fitting groove 15d into which the wedge member 15 is fitted is formed in an annular shape on the bottom surface 15a.

The wedge member 16 is, as shown in FIG.
5 is an annular body that is divided into two parts by a portion through which the part 1 passes. As shown in FIG. 5, the cross-sectional shape is tapered as the distance from the fitting protrusion 16a fitted in the fitting groove 15d increases. (That is, the wedge member 16 has a cross-sectional wedge shape that tapers from the inner peripheral side to the outer peripheral side). In particular, the tip portion 16b is thinner by shaving a portion 16c shown by oblique lines in FIG.
When the forked branches 13a and 13b are inserted between the forked branches 13a and 13b to expand them, the forked branches 13a and 13b are formed to provide an escape space for causing bending deformation. By providing this escape space, bifurcation 1
Since the members 3a and 13b can be sufficiently bent and deformed, the seal member 13 can be smoothly attached. Further, a radius is attached to the tip portion 16b, and the forked branches 13a and 13a are provided along the radius.
The space between b is divided smoothly. Similarly, as shown in the cross section of FIG. 5, the wedge member 16 is formed with a pair of engagement grooves 16d with which a pair of engagement protrusions 13c of the seal member 13 described later are engaged.

Although the wedge member 16 of the present embodiment is formed in advance, as another method, for example, the seal member 13 is inserted into the seal member mounting groove 15 without using it.
Is inserted into the space formed between the forked branches 13a and 13b of the sealing member 13 and the bottom surface 15a of the sealing member mounting groove 15, and then the molten resin is injected into the space formed between the forked branches 13a and 13b. The same method as the wedge member 16 can be attached by hardening the molten resin in a state where is spread.

As shown in FIG. 6, the seal member 13 is an annular body that is divided into two parts by a portion through which the valve rod 11 passes, and as shown in FIG.
a and 13b, the engagement groove 16d of the wedge member 16
Is formed with a pair of the engagement projections 13c. A gap g is formed between the forked branches 13a and 13b, and when it is mounted in the seal member mounting groove 15,
They can be pressed close to each other. Further, in the cross section of FIG. 7, the outer peripheral surface 13d abutting on the inner peripheral surface 10a of the valve box 10 is a surface inclined in the turning direction (the white arrow direction in the figure) when the valve body 12 closes the flow path. It has become. On the other hand, as shown in FIG. 3, a projection 10b is formed in an annular shape on the inner peripheral surface 10a of the valve box 10 along a portion where the seal member 13 contacts when the flow path is closed. The part 10b is formed with a sealing surface 10c to which the outer peripheral surface 13d of the sealing member 13 can be in close contact. Therefore, the valve body 12 is turned to rotate these outer peripheral surfaces 1.
3d and the sealing surface 10c are brought into close contact with each other so that the valve body 12
The gap between the outer periphery of the valve body and the inner peripheral surface 10a in the valve box 10 is sealed so that the flow path can be closed. Note that the seal member 13 is not limited to the above-described two-part structure, and for example, a seal member 13 ′ which is an integrated annular body as shown in FIG. 11 may be employed. Reference numeral 13a 'in the figure indicates a through hole through which the valve rod 11 passes.

[0026] As the material of the sealing member 13, hardness 45H _A ~75H _A (H _A is water rubber standard) rubber material having a range of preferably, the material of the wedge member 16, hardness 85H _{A to} 95H _A and sealing member 1
A rubber material having a hardness of more than 3 is preferred. More preferably, a combination of a seal member 13 having a hardness of 65 _HA and a wedge member 16 having a hardness of 90 _HA is used.

Seal member 1 for butterfly valve described above
The mounting method 3 is performed according to the following procedure.
That is, in the wedge member mounting step, the preformed wedge member 16 is inserted into the bottom surface 15a in the seal member mounting groove 15 having a dovetail cross-sectional shape formed by opening along the outer peripheral edge of the valve body 12. Then, the fitting projection 16a is attached so as to fit into the fitting groove 15d. At this time, if necessary, an adhesive is applied between the fitting projection 16a and the fitting groove 15d, and then attachment is performed.

In the step of inserting the seal member 13 after the step of attaching the wedge member, the elastic members 13a and 13b are bifurcated so that the cross section as viewed in a virtual plane passing through the axis thereof is expanded toward the inner periphery. Is pressed so that the forked branches 13a and 13b approach each other, and then inserted into the seal member mounting groove 15. Note that an adhesive is applied to the seal member 13 and the like before insertion as necessary.

In the step of expanding the seal member 13 after the insertion step, the seal member 13 is further inserted into the seal member mounting groove 15, and the wedge member 16 pushes and expands the forked portions 13 a and 13 b again to seal the seal member 13. By increasing the thickness in the mounting groove 15, the mounting is completed as shown in FIG. At this time, each of the engagement protrusions 13c of the seal member 13 is engaged with each of the engagement grooves 16d of the wedge member 16, and the seal member 13 and the wedge member 16 are non-separably coupled.

According to the butterfly valve of the present embodiment, sealing is performed instead of mounting a large valve seat so as to cover the entire flow path formed in the valve box as in a conventional butterfly valve. Since a minimum required configuration in which the annular seal member 13 is provided only on the peripheral portion of the valve body 12 is employed, for example, when rubber is used as the material, the amount of rubber used is smaller than in the conventional case. It becomes possible to provide an environmentally friendly butterfly valve. Further, since the seal member 13 of the present embodiment can be fixed simply by inserting it into the seal member mounting groove 15 to which the wedge member 16 is mounted, it is possible to easily and surely mount and fix the seal member 13 as compared with the related art. Become.

Further, according to the butterfly valve of the present embodiment,
If the hardness of the sealing member 13 is 45H _A~ 75H_ARange and
And the hardness of the wedge member 16 is 85H_A~ 95H_AIn the range and
By making the hardness higher than that of the seal member 13, the seal
The sealing member 13 is inserted into the sealing member mounting groove 15 of the valve body 12.
When inserted, the wedge member 16 has a negative
The inner peripheral portion of the seal member 13 is securely
Between the two branches 13a and 13b
The sealing member 13 can be firmly attached to the valve body 1
2 can be fixed in the seal member mounting groove 15.
You.

Further, according to the butterfly valve of the present embodiment, at the joint surface between the wedge member 16 and the seal member 13,
An engagement groove 13d is formed on the wedge member 16 with the engagement protrusion 13c formed on the seal member 13.
Is formed, when the seal member 13 is inserted and fixed in the seal member mounting groove 15, the engagement protrusion 13c and the engagement groove 16
d engages the seal member 13 and the wedge member 16 so that they cannot be separated from each other, and the inner peripheral portion of the seal member 13 can be maintained in a fat state in the seal member mounting groove 15. It is possible to more reliably fix the inside of the seal member mounting groove 15. Note that a configuration may be adopted in which an engagement protrusion is formed on the wedge member 16 side and an engagement groove is formed on the seal member 13 side, and these are engaged with each other.
In this case, the same effect can be obtained.

According to the butterfly valve of the present embodiment, the fitting projection 16a is formed on the wedge member 16 side at the joint surface between the bottom surface 15a of the seal member mounting groove 15 and the wedge member 16, and the seal member is formed. A fitting groove 15d in which the fitting protrusion 16a fits is formed in the mounting groove 15 side, and the bottom surface 15a is fitted so that the fitting protrusion 16a and the fitting groove 15d fit.
By mounting the wedge member 16 on the bottom surface, the wedge member 16 can be easily and accurately positioned and fixed to the bottom surface 15a of the seal member mounting groove 15. In addition, seal member mounting groove 1
A configuration may be adopted in which a fitting projection is formed on the side 5 and a fitting groove is formed on the side of the wedge member 16 and these are fitted together. In this case, the same effect can be obtained. Become.

Further, according to the butterfly valve of the present embodiment, the annular projection 10b is formed on the inner peripheral surface 10a of the valve box 10 along the portion where the seal member 13 abuts when the flow path is closed. As a result, when the flow path is closed by the valve body 12, the protrusion 1
0b is hardly inserted into the seal member 13, and the compressive force between the two can be concentrated on the biting portion. Therefore, the surface pressure between the seal member 13 and the inner peripheral surface 10a is increased to further improve the sealing performance. It becomes possible.

In the present embodiment, the wedge member 16
Is divided into two parts so as to avoid only the place where the valve stem 11 passes. However, the present invention is not limited to this two-partitioned structure, and adopts a structure that is finely divided into three or more parts along the circumferential direction. Is also good. In the present embodiment, the wedge member 16
The seal member 13 is made of rubber, but is not limited thereto.
The material may be appropriately changed according to design conditions. In the present embodiment, the engagement protrusion 13c and the engagement groove 16d between the seal member 13 and the wedge member 16 are formed one by one. However, the present invention is not limited to this, and two or more pairs are provided. A configuration may be adopted.

Next, a second embodiment of the butterfly valve according to the present invention will be described below with reference to FIG. In the description of the present embodiment, the description will be made focusing on the points that are particularly different from the first embodiment, and the description will be omitted because the other components are the same as those of the butterfly valve of the first embodiment. I do. FIG. 8 is a drawing corresponding to FIG. 3 described in the first embodiment, and shows a portion B in FIG. The butterfly valve of the present embodiment
As compared with the butterfly valve of the embodiment,
3 in that the contact area between the valve body 3 and the inner peripheral surface 10a of the valve box 10 is reduced to increase the surface pressure. That is, the sealing surface 10 that is in surface contact with the outer peripheral surface 13d of the sealing member 13
c, instead of the protrusion 10b having
An annular linear projection 20 (having a triangular shape in cross section) is formed on the inner peripheral surface 10a of the valve box 10 in line contact with the outer peripheral surface 13d of the valve case 10. According to the butterfly valve of the present embodiment,
The same effect as the effect described in the first embodiment can be obtained, and the contact between the seal member 13 and the inner peripheral surface 10a is linear contact, so that the surface pressure is increased and the It is also possible to enhance the performance.

Next, a third embodiment of the butterfly valve of the present invention will be described below with reference to FIG. In the description of the present embodiment, the points that are particularly different from the first embodiment will be mainly described, and the other parts are the same as those of the butterfly valve of the first embodiment, and the description thereof will be omitted. I do. FIG. 9 is a drawing corresponding to FIG. 3 described in the first embodiment, and shows a portion B in FIG. The butterfly valve of the present embodiment
As compared with the butterfly valve of the embodiment,
3 instead of the flat outer peripheral surface 13d,
The difference is that an outer peripheral edge 21 having a cross section that tapers toward the inner peripheral surface 10a of the valve box 10 is formed in an annular shape, and that the protrusion 10b is omitted from the inner peripheral surface 10a of the valve box 10. ing. FIG. 9 shows a state in which the valve body 12 is closed, and the outer peripheral edge 21 is tightly sealed by being deformed by contact with the inner peripheral surface 10a. According to the butterfly valve of the present embodiment, the same effect as that described in the first embodiment can be obtained, and further, since the machining of the protrusion 10b is unnecessary, the manufacturing cost is reduced. It is also possible.

Next, a fourth embodiment of the butterfly valve of the present invention will be described below with reference to FIG. In the description of the present embodiment, the points that are particularly different from the first embodiment will be mainly described, and the other parts are the same as those of the butterfly valve of the first embodiment, and the description thereof will be omitted. I do. FIG. 10 is a drawing corresponding to FIG. 3 described in the first embodiment, and FIG.
The part is shown. Compared with the butterfly valve of the first embodiment, the butterfly valve of the present embodiment includes a seal mechanism 22 similar to the seal mechanism provided on the outer peripheral edge of the valve body 12 inside the inner peripheral surface 10 a of the valve box 10. Is particularly different. According to the butterfly valve of the present embodiment, it is possible to obtain the same effects as those described in the first embodiment.

[0039]

According to the butterfly valve of the first aspect of the present invention, a large valve seat is not mounted so as to cover the entire flow path formed in the valve box as in the conventional butterfly valve. Since it adopts a configuration in which an annular seal member is provided only on the peripheral portion of the valve element, which is the minimum necessary for performing sealing, for example, when rubber is used as a material, the use of rubber is It is possible to provide an environmentally friendly butterfly valve with a small amount. Further, since the seal member of the present invention can be fixed simply by inserting it into the seal member mounting groove to which the wedge member is mounted, it is also possible to easily and surely mount and fix the seal member as compared with the related art.

According to the butterfly valve of the second aspect, the hardness of the seal member is in the range of 45 to 75, the hardness of the wedge member is in the range of 85 to 95, and is higher than the hardness of the seal member. By doing so, when the seal member is inserted into the seal member mounting groove of the valve body, the wedge member is securely deformed by losing the hardness of the seal member, and reliably presses between the forked branches of the inner peripheral portion of the seal member. Since the seal member can be spread and thickened, the seal member can be firmly fixed in the seal member mounting groove of the valve body.

According to the third aspect of the present invention, the engagement projection is formed on one of the joining surfaces of the wedge member and the seal member, and the engagement projection is engaged with the other. By forming the engagement groove, when the seal member is inserted and fixed in the seal member mounting groove, the engagement protrusion and the engagement groove are engaged, so that the seal member and the wedge member cannot be separated from each other. Since the inner peripheral portion of the seal member can be kept thick in the seal member mounting groove, the seal member can be more securely fixed in the seal member mounting groove.

According to the butterfly valve of the fourth aspect, a fitting projection is formed on one of the joint surface between the bottom surface of the seal member mounting groove and the wedge member, and the fitting projection is formed on the other. Is formed, and the wedge member is attached to the bottom surface so that the engagement protrusion and the engagement groove are fitted, so that the wedge member can be easily and accurately attached to the bottom surface of the seal member attachment groove. Positioning and fixing can be performed.

According to the butterfly valve of the fifth aspect, the projection is formed on the inner peripheral surface of the valve box along the portion where the sealing member abuts when the flow path is closed, so that the valve body is formed. When the flow path is closed with the protrusion, the protruding part gets into the sealing member, and the compressive force can be concentrated on the biting portion, so that the surface pressure between the sealing member and the inner peripheral surface of the flow path is increased. It is possible to further improve the sealing performance.

According to the method of attaching a seal member to a butterfly valve according to the sixth aspect of the present invention, the seal member is inserted into the seal member attachment groove, and the gap between the two branches is pushed and widened by the wedge member. Since it can be fixed, it is possible to easily and surely attach and fix it as compared with the related art.

[Brief description of the drawings]

FIG. 1 is a view showing a first embodiment of a butterfly valve according to the present invention, in which a left half of the paper is a side profile and a right half of the paper is a cross-sectional view showing an internal structure.

FIG. 2 is a diagram showing the butterfly valve,
It is the view seen from the -A line side.

FIG. 3 is a diagram showing a main part of the butterfly valve, and is an enlarged view of a portion B in FIG. 2;

FIG. 4 is a front view showing a wedge member which is a component of the butterfly valve.

FIG. 5 is a view showing the wedge member of the butterfly valve, and is an enlarged cross-sectional view taken along line CC of FIG. 4;

FIG. 6 is a front view showing a seal member which is one component of the butterfly valve.

FIG. 7 is a view showing the seal member of the butterfly valve, and is an enlarged cross-sectional view taken along line DD of FIG. 6;

8 is a view showing a second embodiment of the present invention, and is an enlarged sectional view corresponding to FIG.

FIG. 9 is a view showing a third embodiment of the present invention, and is an enlarged sectional view corresponding to FIG. 3;

FIG. 10 is a view showing a fourth embodiment of the present invention, and is an enlarged sectional view corresponding to FIG. 3;

FIG. 11 is a front view showing a modification of the seal member according to the first to fourth embodiments of the present invention.

FIG. 12 is a side view showing a conventional butterfly valve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Valve box 10a ... Inner peripheral surface 10b, 20 ... Protrusion 11 ... Valve stem 12 ... Valve body 13, 13 '... Seal member 13a, 13b ... Bifurcation branch 13c: engagement projection 15: seal member mounting groove 15a: bottom surface 15d: engagement groove 16a: engagement protrusion 16d: engagement groove

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Mikio Araki 1-3-3 Kyobashi, Chuo-ku, Tokyo Inside Maezawa Kogyo Co., Ltd. Maezawa Kogyo Co., Ltd. F-term (reference) 3H052 AA02 BA02 BA25 BA26 CA03 CA23 CA26 CA34 EA02

Claims (6)

[Claims] 1. A valve box in which a cylindrical flow path through which a fluid flows is formed, a valve stem supported in the flow path perpendicularly and rotatably in a flow direction of the fluid, and the valve. A butterfly valve, which is fixed to a rod and rotates to open and close the flow path. A dovetail groove in a cross-sectional view formed at an outer peripheral edge of the valve body so as to open along the outer peripheral edge. A sealing member mounting groove having a shape of a circle is formed, and an inner peripheral portion facing the bottom surface of the sealing member mounting groove is formed of an elastic body that is bifurcated and branched so as to expand toward the bottom surface in the sealing member mounting groove. A seal member is inserted, and a wedge member is provided on the bottom surface of the seal member mounting groove to be inserted between the forked branches and to expand them in a direction to separate them from each other. Can be in close contact with the inner peripheral surface of the flow path when the flow path is closed Butterfly valve, characterized. 2. The butterfly valve according to claim 1, wherein the sealing member is a rubber material having a hardness of 45 to 75, and the wedge member has a hardness of 85 to 95 and the sealing member. Butterfly valve characterized by being a rubber material having higher hardness. 3. The butterfly valve according to claim 1, wherein an engagement projection is formed on one of the joining surfaces between the wedge member and the seal member, and the engagement projection is formed on the other. A butterfly valve, wherein an engagement groove is formed to engage with the projection. 4. The butterfly valve according to claim 1, wherein a fitting projection is formed on one of a joint surface between the bottom surface of the seal member mounting groove and the wedge member. A butterfly valve is provided on the other side with a fitting groove in which the fitting protrusion is fitted. 5. The butterfly valve according to claim 1, wherein the inner peripheral surface of the valve box protrudes along a portion where the seal member contacts when the flow path is closed. A butterfly valve, wherein a butterfly portion is formed. 6. A valve box in which a cylindrical flow path through which a fluid flows is formed, a valve stem vertically and rotatably supported in the flow direction of the fluid in the flow path, and the valve. A valve element that is fixed to a rod and rotates to open and close the flow path, and is attached to an outer peripheral edge of the valve element and closely contacts an inner peripheral surface of the flow path when the valve element closes the flow path. A method of attaching the seal member to the valve body of a butterfly valve provided with a seal member having a seal member mounting groove having a dovetail-shaped cross-sectional view formed along an outer peripheral edge of the valve body. A wedge member attaching step of attaching a wedge member to the bottom surface; and a seal member, which is an elastic body that is bifurcated so that a cross section viewed in an imaginary plane passing through an annular and axial line thereof expands toward the inner periphery. An insertion step of pressing the branches so as to approach each other and then inserting the branches into the seal member mounting groove; A step of pushing and spreading the bifurcated branch again with the wedge member to increase the thickness in the seal member attachment groove.