JPH11230388A - Check butterfly valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a butterfly valve provided with a check function at a low cost by providing a valve element capable of being moved in the fluid flowing direction and to be rotated with regulation at a starting point of the movement and to be rotated around an eccentric rotary shaft at the end of the movement in a valve casing. SOLUTION: In the case of flowing the fluid, since the pressure is applied in the right direction, a valve element 4 and a shaft 3 are moved right by the length a', and a pin 6b is removed from a key groove 6a. A radial position of the valve element 4 from the shaft 3 is changed from a position R1 to a position R2 so as to be rotated clockwise. At this stage, the shaft 3 is eccentrically fitted to the valve element 4, and since the pressure is applied to a projecting part 4b of the valve element 4, a clockwise moment is generated around the shaft 3 so as to rotate the valve element 4. With the rotation of the valve element 4, a stopper provided in a shaft end abuts on a stopper receiver so as to stop the rotation of the shaft 3 at the predetermined angle, and a check butterfly valve 1 is held in the opening condition. On the hand, when the fluid is reversely flowed, the projecting part 4b of the valve element 4 is made to pressure-contact with a valve seat 5 so as to close the valve.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a technique suitable for use in a check butterfly valve.

[0002]

2. Description of the Related Art Conventionally, butterfly valves have been used in piping. Such valves include, for example, a butterfly valve B1 as shown in FIG. 12 and a check valve as shown in FIG. The check butterfly valve B2 has been applied as having a function. As the check butterfly valve B2, a half-circle type two-piece valve body B3, B3 having a check function by a spring B4 has been put to practical use as a product.

[0003]

However, when the spring B4 and the like are provided in the valve, such as the check butterfly valve B2, the replacement operation is not easy, and there is a problem that it takes time for maintenance. In addition, there is a problem that the number of components in the pipe is increased as compared with the butterfly valve B1 or the like having no check function, and there is a possibility that durability and reliability may be lacked. Also, a structure in which the shaft B5 is eccentric in the flow direction with respect to the valve body, such as a butterfly valve B1 as shown in FIG. 12, has a problem in airtightness and the like, and can have a check function. Absent.

[0004] The present invention has been made in view of the above circumstances, and aims to achieve the following objects. Improve durability and reliability. Improve ease of maintenance. To provide a check butterfly valve which is integral and has a check function.

[0005]

According to the present invention, the valve case and the rotating shaft are eccentric and can move in the flow direction of the fluid, and the rotation is restricted at the start point of the movement, but is rotatable at the end point of the movement. The above problem was solved by providing a valve body supported in the valve box.

Further, in the present invention, the above-mentioned problem has been solved by providing a valve box and a valve element which is rotatably helically supported in the valve box while the rotation axis is eccentric.

In the present invention, the valve box and the rotating shaft are eccentric and movable in the direction of fluid flow.
At the start point of the movement, the rotation is regulated, but at the end point of the movement, a means having a valve body supported in the valve box so as to be able to rotate spirally may be employed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of a check butterfly valve according to the present invention will be described with reference to the drawings. FIG.
2, reference numeral 1 denotes a check butterfly valve, 2 denotes a valve case, 3 denotes a shaft, 4 denotes a valve body, 5 denotes a valve seat, 6 denotes switching means,
Reference numeral 7 denotes a rotational position regulating means.

As shown in FIGS. 1 and 2, the check butterfly valve 1 has a valve case 2 and a valve body 4 rotatably supported by a shaft 3 in the valve case 2. The shaft 3 is shown in FIG.
(B) is movable in the direction of flow of the fluid indicated by arrow F so as to be supported by the shaft supporting portion 2a of the valve box portion 2;
Are provided with switching means 6 for switching the rotation state of the valve body 4 and rotation position regulating means 7 for regulating the rotational position of the shaft 3. Since the shaft 3 is eccentric as described later, the valve box 2 has a downstream inner dimension larger than the upstream inner dimension of the valve 4 so that the valve 4 can rotate. Set to a large value.

For example, as shown in FIG. 1B, a shaft 3 is integrally provided at an eccentric position of a metal valve body 4. The rotating ends 4a, 4a of the valve element 4 are bent in a direction opposite to the flow direction F of the fluid to easily receive the pressure from the fluid, and the rotation of the valve element 4 indicated by an arrow R in FIG. A protrusion 4b is provided to facilitate rotation. In addition, the outer shape of the valve element 4 enhances the sealing performance with a valve seat 5 described later,
Is set as a substantially spherical shape so as not to hinder the rotation of.

For example, a resin valve seat (valve frame portion) 5
As shown in FIGS. 1 (a) and 1 (b), the valve frame portion 5 and the valve body 4 are integrally disposed outside the protruding portion 4b inside the valve box portion 2 and around the shaft support portion 2a. Seal between the two. The inner shape of the valve frame portion 5 is designed as a rotation trajectory when the valve body 4 moves in the flow direction, as described later, to enhance the sealing performance at the time of a non-return check.

The switching means 6, as shown in FIG.
Recess (keyway) 6 provided in shaft support 2a of valve box 2
a, and a convex portion (pin) 6b provided on the shaft 3 corresponding to the concave portion 6a, and the diameter of the circular section of the shaft supporting portion 2a is larger than the diameter of the shaft 3 by the length a '. Is set. The relationship between the key groove 6a and the pin 6b is as follows.
Are set so as to satisfy the relationship of a ′> a, and the dimension a ′ of the gap between the shaft 3 and the shaft support 2a is set to satisfy the relationship of a ′> a.
When pressure is applied by a fluid in the direction indicated by arrow F in (a), as shown in FIG. 2 (b), the shaft 3 and the valve body 4 integrated with the shaft 3 have a length indicated by a '. Move in the flow direction.

As shown in FIG. 1 (c), the rotational position regulating means 7 includes a stopper 7 provided on the shaft 3 outside the shaft support 2a.
a, and a stopper receiver 7b provided on the valve box portion 2 corresponding to the stopper 7a.
Regulate the opening of The angle α between the stopper receivers 7b, 7b is set at α = 45 °, and the angle of the open valve body 4 with respect to the closed valve body 4 is set at approximately 45 °. Any angle position can be set.

In such a check butterfly valve 1, the shaft 3 is fixed and closed by fitting the keyway 6a of the switching means 6 and the pin 6b in a state where no fluid flows. At this time, the outside of the valve body 4 is tightly contacted with the valve frame portion 5 to seal with metal and resin.

Next, when the fluid flows, FIG.
Pressure is applied in the direction indicated by the arrow F in (b), the valve body 4 and the shaft 3 move by the length a 'in the flow direction indicated by the arrow F, and the pin 6b comes off the keyway 6a. At the same time, FIG.
As shown in (b), since the shaft 3 and the valve body 4 move in the flow direction F by the length a ', the radius of rotation of the valve body 4 from the shaft 3 changes from R1 to R2. , FIG.
It becomes rotatable in the direction indicated by the arrow R in FIG. Then
Since the mounting position of the shaft 3 with respect to the valve body 4 is eccentric, and pressure is applied to the protruding portion 4b of the valve body 4, a moment about the shaft 3 acts in the direction indicated by the arrow R in FIG. The body 4 rotates. By the rotation of the shaft 3 and the valve body 4, the stopper 7a comes into contact with the stopper receiver 7b, the rotation angle of the shaft 3 is set to α, and the check butterfly valve 1 is opened.

Next, when the fluid flows backward, the fluid exerts a pressure on the rotating end 4a and the protruding portion 4b of the valve body 4 in the direction opposite to the arrow F in FIG. A moment about the axis acts, and the valve body 4 rotates in the direction opposite to the arrow R in FIG. Then, the pin 6b is
a, the shaft 3 moves by the length a 'in the direction opposite to the arrow F, and the outside of the protruding portion 4b of the valve body 4 comes into close contact with the valve frame portion 5, so that the check butterfly valve 1 Is closed.

In such a check butterfly valve 1, since the outside of the protruding portion 4b and the valve frame portion 5 are sealed in the closed state, compared to a type in which a linear seal around the valve body is performed, Sealability can be significantly improved. The stopper 7a and the stopper receiver 7b
Can be set up to 90 °. Even when the angle α between the stopper 7a and the stopper receiver 7b is set to 90 °, the shaft 3 is eccentric with respect to the center of the valve box 2,
The non-return function works due to the rotational moment generated by the projection 4b of the valve body 4.

Next, a second embodiment of the check butterfly valve according to the present invention will be described with reference to the drawings. In the present embodiment shown in FIGS. 3 to 7, reference numeral 11 denotes a check butterfly valve, 12 denotes a valve case, 13 denotes a shaft, 14 denotes a valve body, 15 denotes a valve seat, 17 denotes a rotational position regulating means, and 18 denotes a shaft. The direction position setting means 19 is a rotary sealing means.

The check butterfly valve 11 is shown in FIGS.
As shown in (1), the valve body 12 has a valve body 14 rotatably supported by a shaft 13 in the valve case 12. The shaft 13 is located in the vertical direction, is movable in the axial direction, is supported by the shaft support portion 12a of the valve box portion 12, and has an upper end on the shaft 3 even when the shaft 13 moves. A seal member (packing) 13a for sealing one end of the shaft 13 and a rotational position regulating means 17 for regulating the rotational position of the shaft 13 are provided at the lower end of the shaft 13 in the axial direction of the shaft 13 by the rotation of the shaft 13. An axial position setting means 18 for setting a position is provided. The valve box part 12 is similar to the first embodiment,
Since the shaft 13 is eccentric, the inner dimension on the downstream side of the valve element 14 is set larger than the inner dimension on the upstream side of the valve element 14 so that the valve element 14 can rotate.

FIG. 3B shows an example of a valve element 14 made of metal.
As shown in FIG. 4 and FIG. 4, a shaft 13 is integrally provided at the eccentric position, and the shaft 13 and the valve element 14 are fixed by a key 13a as shown in FIG. 7B. And, as shown in FIG. 4, the planar shape orthogonal to the flow direction of the valve element 14 is such that both rotating end portions 14 a
Are in a straight line parallel to the axis 13, and the shape of the upper end 14b and the shape of the lower end 14c are substantially arc-shaped.

For example, a resin valve seat (valve frame portion) 15
As shown in FIGS. 3 and 4, the valve element 14 is integrally disposed inside the valve box 12 and around the shaft support 12a.
Seal with.

As in the first embodiment, as shown in FIG. 3C, the rotation position regulating means 17 includes a stopper 17a provided on the shaft 13 outside the shaft support 12a, and the stopper 1a.
Stopper receiver 17 provided on valve box part 12 corresponding to 7a
b to regulate the rotation of the shaft 13 and the opening of the valve element 14. In the present embodiment, the stopper receiver 1
The angle α between 7b and 17b is set to α = 90 °, and the angle of the open valve body 14 with respect to the closed valve body 14 is set to approximately 90 °.

The axial position setting means 18 sets the axial position of the shaft 13 by rotation.
As shown in (a), an inclined portion 18A provided on the shaft support portion 12a of the valve box portion 12 and inclined upward in the rotation direction of the shaft 13
And a lower end portion 13b of the shaft 13 corresponding to the inclined portion 18A.
And an abutment portion 18B disposed on the front side. Inclined part 18A
Is a helical surface 18a that rotates upward at a predetermined inclination angle with respect to the axis of the shaft 13 and is connected to the lower end of the helical surface 18a to set the closed position of the valve body 14 by the rotational position of the shaft 13. And a contact groove 18B
Is a spiral surface 18a of the inclined portion 18A when the valve body 14 is closed.
And a key portion 18d connected to the lower end of the spiral surface 18b. Contact part 13
The key portion 18b of B comes into contact with the spiral surface 18a of the inclined portion 18A to enable the shaft 13 to rotate helically, thereby setting the height position of the shaft 13, and corresponding to the key groove 18c. The closed position of the body 14 is set by the rotation position of the shaft 13. In FIG. 5A, the slope 18A is described for the sake of explanation.
Is described in a columnar shape having the same diameter as the shaft 13.

As shown in FIGS. 3 to 7, the sealing means 19 includes an upstream seal member 19A, a downstream seal member 19B, a shaft seal member 19C, recesses 19D, 19D for sealing the valve body 14 in a spirally rotatable manner. Is provided. For example, an upstream seal member 19A and a downstream seal member 19B made of resin are provided integrally with the valve frame 15, and a shaft seal member 13C is integrated with the valve body 14. The recess 19D is
The upstream seal member 19A and the downstream seal member 19B are provided on the valve body 14 and allow the valve body 14 to rotate to an open state in a state where the upstream seal member 19A and the downstream seal member 19B are in contact with a rotating seal surface 19c described later. Here, as shown in FIGS. 3B and 4, the upstream seal member 19 </ b> A attaches the upper end portion of the valve body 14 to the one rotating end portion 14 a.
To the shaft 13, and the downstream seal member 19 </ b> B seals the upper end portion of the valve body 14 from the other rotating end 14 a to the shaft 13. The upstream seal member 19A and the downstream seal member 19B can have lower end shapes that are inclined along the rotation trajectory so that the valve body 14 can be spirally rotated. The shaft seal member 19C seals the upstream seal member 19A and the shaft 13, and seals the downstream seal member 19B and the shaft 13. As shown in FIGS. 6B and 7, the shaft seal member 19 </ b> C has a cylindrical shape coaxial with the shaft 13, and has a diameter larger than the flow direction dimension of the valve body 14 near the shaft 13. Rotating seal surface 19c,
Are provided up to the inside of the concave portions 19D, 19D. The upstream seal member 19A, the downstream seal member 19B, the rotary seal surfaces 19c, 19c, and the concave portion 19D,
The 19Ds are arranged at substantially axially symmetric positions near the axis 13.

In the state where there is no flow of fluid, the check butterfly valve 11 is fitted with the key portion 13d of the contact portion 18B and the key groove 13c of the inclined portion 18A in the axial position setting means 18 so that the check valve can be rotated. 13 is fixed, and FIG.
As shown in (2), the check butterfly valve 11 is closed.
At this time, both rotating end portions 14a and lower end 14c of the valve body 14
And the upper end 14b of the valve body 14
In addition, the shaft seal member 19C is brought into close contact with the upstream seal member 19A and the downstream seal member 19B by the rotating seal surface 19c, thereby sealing with metal and resin.

Next, when the fluid flows, FIG.
Since pressure is applied in the direction indicated by arrow F in FIG. 3B and the mounting position of the shaft 13 with respect to the valve element 14 is eccentric, the valve element 14 which has received the pressure has the direction indicated by arrow R in FIG. Axis 1
A moment about 3 acts, and the shaft 13 rotates. According to this rotation, the axial position setting means 18 causes the contact portion 1
8B is disengaged from the key groove 18c of the inclined portion 18A, and the key portion 18d of the contact portion 18B is disengaged from the inclined portion 1A.
8A, the contact portion 1 is slid.
8B ascends the inclined portion 18A along the angle of the spiral surface 13a. At the same time, as shown in FIG.
4 rises as shown by the arrow U in FIG. 3A while spirally rotating, and the stopper 17a shown in FIG. 3C comes into contact with the stopper receiver 71b, so that the rotation angle of the shaft 13 is reduced. It is set to α and becomes open.

At this time, as shown in FIG. 7B, the upstream seal member 19A and the downstream seal member 19B slide in contact with the rotary seal surface 19c and enter the inside of the concave portion 19D, whereby the valve element 14 is opened. State.

Next, when the fluid flows backward, the fluid exerts a pressure on the valve body 14 in the direction opposite to the arrow F in FIG. 14 rotates in the direction opposite to the arrow R in FIG. At the same time, the key portion 18d of the contact portion 18B is
8A, the contact portion 1 is slid.
8B descends the inclined portion 18A along the angle of the spiral surface 18a. The key portion 18d of the contact portion 18B is fitted into the key groove 18c of the inclined portion 18A, so that the shaft 13
And the check butterfly valve 11 is closed. At this time, the rotating end portions 14a and the lower end 14c on both sides of the valve body 14 are in close contact with the valve frame portion 15, and the upper end portion 14b of the valve body 14 and the shaft sealing member 19C of the shaft 13 are connected to the upstream sealing member 19A and the downstream sealing member 19A. Seal tightly with 19B.

Here, in the axial position setting means 18, the key portion 18 of the contact portion 18 B is rotated in accordance with the rotation of the shaft 13.
d slides while rotating with the helical surface 18a of the inclined portion 18A, so that the contact portion 18B descends the inclined portion 18A along the angle of the helical surface 13a. Due to the weight of the valve body 14, a moment about the rotation axis acts in a direction opposite to the arrow R, and the valve body 14
It rotates in the direction opposite to the arrow R in (b). Therefore, the valve element 1
The flow rate can be controlled by the check butterfly valve 11 from the difference between the moment of the fluid velocity and the moment of its own weight of No. 4.

The shaft 13 may be positioned at an angle other than vertical, and the shaft 13 may be provided with an urging means for applying an urging force in the direction of the axial position setting means 18 to have a check function. ,

Hereinafter, a third embodiment of the check butterfly valve according to the present invention will be described with reference to the drawings. 8 to 11, reference numeral 21 denotes a check butterfly valve, 22 denotes a valve box, 23 denotes a shaft, 24 denotes a valve body, 25 denotes a valve seat, 26 denotes a switching means, and 27 denotes a rotational position restriction. Means, 28
Is an axial position setting means, and 29 is a rotary sealing means.

The check butterfly valve 21 is shown in FIGS.
As shown in FIG. 1, a valve box 22 and a shaft 23
And a valve element 24 rotatably supported by the valve. The shaft 23 is located in the vertical direction, is movable in the axial direction thereof, and is movable in the fluid flow direction indicated by an arrow F in FIG. 8A, and is supported by the shaft support portion 22a of the valve box portion 22. In addition, the shaft 23 is provided with switching means 26 for switching the rotation state of the valve body 24 and rotation position regulating means 27 for regulating the rotational position of the shaft 23. At the upper end of the shaft 23, a sealing member (packing) 23a for sealing one end of the shaft 23 even when the shaft 23 is moved, and a rotation position regulating means 27 for regulating the rotational position of the shaft 23 are provided. An axial position setting means 28 for setting an axial position of the shaft 23 by rotation is provided at a lower end of the shaft 23. The valve box part 22 is
As in the first and second embodiments, since the shaft 23 is eccentric, the valve 2 is rotated so that the valve 24 can rotate.
4 is set to be larger than the inner size of the valve element 24 on the upstream side.

FIG. 8 (b) shows an example of a metal valve element 24.
As shown in FIG. 5, the shaft 23 is provided integrally at the eccentric position, and the shaft 23 and the valve body 24 are
Fixed by key. As the planar shape orthogonal to the flow direction of the valve element 24, the rotating ends 24a on both sides thereof with respect to the shaft 23 are in a straight line parallel to the shaft 23, as in the second embodiment. And the shape of the lower end are substantially arc-shaped. Then, the rotating ends 24a, 2 of the valve body 24
4a, a protruding portion 24b which is bent in a direction opposite to the flow direction F of the fluid to easily receive pressure from the fluid and facilitates rotation of the valve element 24 indicated by an arrow R in FIG. You.

For example, a valve seat (valve frame portion) 25 made of resin
As shown in FIGS. 8 (a) and 8 (b), are disposed integrally inside the valve box 22 and around the shaft support 22a to seal between the valve frame 25 and the valve element 24. .
The inner shape of the valve frame 25 is, as described later, the valve body 2.
4 is designed as a rotation trajectory when it moves in the flow direction, thereby improving the sealing performance at the time of the check.

The switching means 26, as in the first embodiment,
It has a concave portion (key groove) provided on the shaft support portion 22a of the valve box portion 22 and a convex portion (pin) arranged on the shaft 23 corresponding to the concave portion. The diameter is set to be larger than the diameter of the shaft 23 by the length a 'shown in FIG. The relationship between the key groove and the pin is such that the dimension a in the center direction of the pin and the dimension a ′ of the gap between the shaft 23 and the shaft support 22a satisfy the relationship a ′> a shown in FIG. 8 and the valve body 24 shown in FIG.
When pressure is applied by a fluid in the direction indicated by arrow F in (a), as shown in FIG. 2, the shaft 23 and the valve body 24 integral with the shaft 23 are moved by the length indicated by arrow F by the length indicated by a '. Move in the flow direction indicated by.

As shown in FIG. 8 (c), the rotation position regulating means 27, as in the first and second embodiments,
Stopper 27a provided on shaft 23 outside shaft support 22a
And a stopper receiver 27b provided on the valve box portion 22 corresponding to the stopper 27a, and regulates the rotation of the shaft 23 and the opening of the valve body 24. In the present embodiment, the angle α between the stopper receivers 27b, 27b is α
= 90 °, and the angle of the open valve body 24 with respect to the closed valve body 24 is set to approximately 90 °.

The axial position setting means 28 is for setting the axial position of the shaft 23 by rotation, and is similar to the second embodiment shown in FIG. An inclined portion 28A provided on the support portion 22a and rising and inclined in the rotation direction of the shaft 23, and a contact portion 28B disposed on the lower end portion 23b of the shaft corresponding to the inclined portion 28A are provided. The inclined portion 28A is provided with a spiral surface 28a that rises while rotating at a predetermined inclination angle with respect to the axis of the shaft 23, and is connected to the lower end side of the spiral surface 28a to change the closed position of the valve body 24 to the rotational position of the shaft 23. And a key groove for setting by the following.
A spiral surface corresponding to the spiral surface 28a of the inclined portion 28A when the valve body 24 is closed, and a key groove connected to the lower end side of the spiral surface are provided. The key portion of the contact portion 28B is the inclined portion 2
8A, the shaft 23 is helically rotatable, the height position of the shaft 23 is set, and the closed position of the valve body 24 is set to the rotation of the shaft 23 in correspondence with the keyway. Set by position.

As shown in FIGS. 8 to 11, the sealing means 29 includes an upstream sealing member 29A, a downstream sealing member 29B, and a shaft sealing member 29C for sealing the valve body 24 so as to be movable in the flow direction and helically rotatable. And recesses 29D, 29
D ′. For example, an upstream sealing member 29 made of resin
A and the downstream seal member 29B are provided integrally with the valve box portion 22, and the shaft seal member 29C is integrated with the valve body 24. The recess 29D is provided in the valve body 24 so that the upstream seal member 29A is rotatable, and the recess 29D 'is
4, the downstream seal member 29B enables the valve body 24 to move in the flow direction and to rotate in a spiral shape. Here, as shown in FIG. 9 to FIG.
9A seals the upper end portion of the valve body 24 from the one rotating end portion 24a to the shaft 23, and the downstream seal member 29B seals the upper end portion of the valve body 24 from the other rotating end portion 24a to the shaft 23. The lower end shape of the downstream seal member 29B is as follows:
The valve body 24 has a shape that is inclined along the rotation trajectory so that the valve body 24 can rotate spirally. The shaft seal member 29C is
The seal between the upstream seal member 29A and the shaft 23 and the seal between the downstream seal member 29B and the shaft 23 are performed. In the shaft seal member 29C, as shown in FIGS. 9 to 11, a seal portion between the upstream seal member 29A and the shaft 23, that is, on the upstream side of the shaft seal member 29C, as in the second embodiment, An upstream rotary sealing surface 29c, which is coaxial with a cylindrical shape and whose diameter is set to be larger than the flow direction dimension of the valve body 24 near the shaft 23, is provided, and the rotary sealing surface 29c extends into the recess 29D. Provided.
As shown in FIG. 9 to FIG. 11, a cylindrical portion coaxial with the shaft 23 and having a diameter near the shaft near the shaft seal member 29 </ b> C is provided at the sealing portion between the downstream seal member 29 </ b> B and the shaft 23. A downstream rotation surface 29d set to be smaller than the flow direction dimension of the valve element 24 is provided. The downstream rotating surface 29d has a length in the radial direction of the shaft 23 and a length in the axial direction of the shaft 23 continuously from the downstream rotating surface 29d, and is located in the fluid flow direction. A moving seal surface 24e is provided. Further, the downstream rotating surface 29d and the moving seal surface 29e are attached to the downstream rotating surface 29d.
An inclined seal surface 29f that is inclined upward around the shaft 23 is provided substantially in the same shape as the inclined portion 28A of the axial position setting means 28 continuously from d and the movable seal surface 29e. A side seal surface 29g is connected to the inclined seal surface 29f, and the lower end shape of the side seal surface 29g is
4 has an inclined shape along its rotation locus so that it can rotate spirally.

In the state where there is no fluid flow, the check butterfly valve 22 fixes the shaft 23 by fitting the key groove of the switching means 26 and the pin, as in the first embodiment. Similarly to the embodiment, the key portion of the contact portion 28B and the inclined portion 28A in the axial position setting means 28 are provided.
The shaft 23 is fixed by fitting into the key groove, and the check butterfly valve 21 is closed. At this time, both the rotating ends 24a and the lower end of the valve body 24 are in close contact with the valve frame 25, and the upper end of the valve body 24 and the shaft seal member 29C
However, the upstream seal member 19 is
A, and the upper end of the valve body 24 and the shaft seal member 29C are in close contact with the downstream seal member 19B by the movable seal surface 29e, the inclined seal surface 29f, and the side seal surface 29g, thereby sealing with metal and resin. .

Next, when the fluid flows, FIG.
Pressure is applied in the direction indicated by the arrow F in (b), the valve body 24 and the shaft 23 move in the direction of the arrow F, the pin comes off the keyway, and the shaft 23 becomes rotatable. At this time, the downstream seal member 29B is moved by the moving seal surface 29e and the inclined seal surface 29e.
The valve body 24 is moved in sliding contact with f and the side sealing surface 29g. Then, as shown in FIG.
Since the valve body 24 moves in the flow direction by the length a 'and the radius of rotation of the valve body 24 from the shaft 23 changes from R1 to R2 as shown in the first embodiment, FIG. It becomes rotatable in the direction indicated by the arrow R in FIG. Then, the mounting position of the shaft 23 with respect to the valve body 24 is eccentric,
Further, since a pressure is applied to the protruding portion 24b of the valve body 24, a moment about the axis 23 acts in a direction indicated by an arrow R in FIG. 8A, and the valve body 24 rotates. At this time, as in the second embodiment, in accordance with the rotation of the valve body 24, the key portion of the contact portion 28B is disengaged from the key groove of the inclined portion 28A and the key of the contact portion 28B When the portion slides on the spiral surface 28a of the inclined portion 28A, the contact portion 28B moves up the inclined portion 28A along the angle of the spiral surface 28a. At the same time, as shown in FIG. 7 of the second embodiment, while the shaft 23 and the valve
As shown by the arrow U in FIG.
a comes into contact with the stopper receiver 27b, so that the shaft 2
The rotation angle of No. 3 is set to α and the state is opened.

At this time, as shown in FIG. 9 (b), the upstream seal member 29A enters the inside of the concave portion 29D, and the downstream seal member 29B slides on the downstream rotary surface 29d and the inclined seal surface 29f. By entering the inside of the recess 29D ', the valve body 24 is opened.

Next, when the fluid is flowing backward, the fluid causes the rotating end 24a and the protruding portion 24b of the valve body 24 to move as shown in FIG.
8B, pressure is applied in the direction opposite to the arrow F, and a moment about the rotation axis acts in the direction opposite to the arrow R, so that the valve body 24
It rotates in the direction opposite to the arrow R in (b). At the same time, the contact part 2
When the key portion 8B slides on the spiral surface 28a of the inclined portion 28A, the contact portion 28B descends the inclined portion 28A along the angle of the spiral surface 28a. And the contact part 28B
Is fitted in the key groove of the inclined portion 28A, and the shaft 23 is moved in the direction opposite to the arrow F by the length a 'described above, so that the pin of the switching means 26 is fitted in the key groove. To fix the shaft 23 and close the check butterfly valve 21. At this time, the outer and lower ends of the rotating ends 24a on both sides of the valve body 24 are in close contact with the valve frame 25, and the upper end of the valve body 24 and the shaft seal member 29C on the shaft 23 are separated from the upstream seal member 29A and the downstream seal member 29A. The member 29B is tightly sealed.

In the axial position setting means 28, the key portion of the contact portion 28B slides while rotating with the spiral surface 28a of the inclined portion 28A in accordance with the rotation of the shaft 23. The helical surface 28a descends along the inclined portion 28A along the angle of the helical surface 28a. Even when the velocity of the fluid decreases, a moment about the rotation axis acts in the direction opposite to the arrow R due to the weight of the valve body 24, and the valve body 24 rotates in the direction opposite to the arrow R in FIG. For this reason, the flow rate can be controlled by the check butterfly valve 21 from the difference between the moment of the fluid velocity and the moment of the weight of the valve body 24.

The axial position setting means 28 may have a structure in which the valve support 22a and the shaft end 23b are screwed into a shallow screw shape.

[0045]

According to the check butterfly valve of the present invention, the following effects can be obtained. (1) Switching means having a concave portion provided in the axial direction of the valve body in the shaft support portion of the valve box and a convex portion arranged on the shaft corresponding to the concave portion is provided. The part is fitted, or the inclined part provided in the shaft support part of the valve box part and inclined upward in the rotational direction of the shaft, and the contact part arranged at the shaft end corresponding to the inclined part By providing, the valve body, the rotation axis is eccentric, can be moved in the flow direction of the fluid, the rotation is restricted at the start point of the movement and can be rotated at the end point of the movement, or because it can be rotated helically, To provide a non-return butterfly valve that is integral and has a non-return function because the valve element can be closed when the flow of the fluid is reversed or the flow velocity decreases due to the force or gravity acting from the fluid. Can be. (2) Since it operates by force acting from fluid or gravity without having an elastic member such as a spring, the number of components in the pipe can be reduced, and as a result, durability and reliability are improved. Can be. (3) As described above, the ease of maintenance can be improved.

[Brief description of the drawings]

FIG. 1A is a side view showing a first embodiment of a check butterfly valve according to the present invention, in which (a) slides against a flow at an axial position;
(B) It is BB sectional drawing in (a), (c) It is AA sectional drawing in (a).

FIGS. 2A and 2B are a cross-sectional view illustrating a switching unit in the check butterfly valve illustrated in FIG. 1 and a view illustrating a movement of a valve body.

3A and 3B show a second embodiment of a check butterfly valve according to the present invention, wherein FIG. 3A is a side view with respect to a flow at an axial position, FIG. 3B is a sectional view taken along line BB in FIG. )
FIG. 4 is a cross-sectional view showing a rotation position regulating unit.

FIG. 4 is a cross-sectional view orthogonal to the flow direction of the check butterfly valve shown in FIG. 3;

5 (a) is a perspective view showing an axial position setting means of the check butterfly valve shown in FIG. 3, and FIG. 3 (b) is a sectional view taken along line AA in FIG. 3 (a). It is.

6A is a side view of the check butterfly valve shown in FIG. 3 with respect to the flow when moving in the axial direction, and FIG. 6B is a perspective view showing a sealing means.

FIGS. 7A and 7B are views showing a sealing means in an open state of the butterfly valve shown in FIG. 3, and FIGS.

8A and 8B show a third embodiment of a check butterfly valve according to the present invention, wherein FIG. 8A is a side view with respect to a flow at an axial position, FIG. 8B is a sectional view taken along line BB in FIG. )
FIG. 4 is a cross-sectional view showing a rotation position regulating unit.

9 is a diagram showing the sealing means in an open state of the butterfly valve shown in FIG. 8, (a), and a diagram (b) showing a downstream rotating surface and a moving sealing surface.

FIG. 10 is a diagram illustrating a butterfly valve shown in FIG. 9 (a);
FIG. 7A is a sectional view (A), a sectional view taken along line BB (b), and a view (c) showing a closed state.

FIG. 11 is a perspective view showing a sealing means in an open state of the butterfly valve shown in FIG. 8;

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

FIG. 13 is a sectional view showing a conventional check butterfly valve.

[Explanation of symbols]

 1, 11, 21 ... check butterfly valve 2, 12, 22 ... valve case 3, 13, 23 ... shaft 4, 14, 24 ... valve element 4a, 14a, 24a ... rotating end 4b, 24b ... protruding part 5 , 15, 25 ... valve seat (valve frame part) 6, 26 ... switching means 6a ... concave part (key groove) 6b ... convex part (pin) 7, 17, 27 ... rotational position regulating means 7a, 17a, 27a ... stopper 7b , 17b, 27b Stopper receiver 13a, 23a Seal member (packing) 18, 28 ... Axial position setting means 18A ... Inclined part 18B ... Contact part 18a ... Spiral surface 18b ... Spiral surface 18c ... Key groove 18d ... Key part 19, 29 ... Sealing means 19A, 29A ... Upstream sealing member 19B, 29B ... Downstream sealing member 19C, 29C ... Shaft sealing member 19D, 29D, 29D '... Recess 19c ... Rotary sealing surface 29c: Upstream rotary seal surface 29d: Downstream rotary surface 29e: Moving seal surface 29f: Inclined seal surface 29g: Side seal surface

Claims (3)

[Claims] 1. A valve box, wherein the rotation axis is eccentric and movable in the direction of fluid flow, rotation is restricted at the start point of movement, but is rotatably supported within the valve box at the end point of movement. A non-return butterfly valve, comprising: 2. A non-return butterfly valve comprising: a valve box; and a valve body having an eccentric rotation shaft and being helically rotatably supported in the valve box. 3. The valve box, wherein the rotation axis is eccentric and movable in the flow direction of the fluid. The rotation is restricted at the start point of the movement, but it is helically rotatable at the end point of the movement. A non-return butterfly valve, comprising: a valve body supported by the valve.