JP3040698B2 - Butterfly valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration control device applied to a main valve of a butterfly valve.

[0002]

2. Description of the Related Art A first conventional example will be described with reference to FIG. FIG. 5 is a sectional view of the first conventional example. The butterfly valve 1 is fixed to a rotating shaft 2 and is supported in a pipe 3. By rotating the rotating shaft 2, the butterfly valve 1 rotates from the fully closed position 4 to the fully open position 5 in the pipe 3, and the flow area of the fluid F can be changed by sequentially changing the opening area. At this time, even if the butterfly valve 1 is vibrated by the force of the fluid F, there is no particular means for damping them. As a second conventional example, a double leaf valve (Japanese Patent Application No. 62-298081),
1278), as a third conventional example, a combination valve (Japanese Patent Application No.
278624) and JP-A-63-135662, which are basically different in shape and structure.

A fourth conventional example will be described with reference to FIG. FIG.
FIG. 4B is a cross-sectional view of the fourth conventional example, and FIG.
It is sectional drawing. In the figure, 1 is a butterfly valve, 2 is a rotary shaft, and the butterfly valve 1 is fixed. Reference numeral 5 denotes a valve box having a butterfly valve 1 therein and connected to a pipe 3. Numeral 6 denotes a projection for fluid guide provided on the inner wall of the valve box 5 so as not to contact the butterfly valve 1. The operation of the fourth embodiment will be described. The projection 6 is intended to rectify the flow. The projection 6 guides the jet flow with the butterfly valve 1 having a small opening degree toward the center of the flow path, and generates cavitation at a location away from the inner peripheral wall of the valve box 5 without generating the cavitation, thereby suppressing vibration of the butterfly valve 1. It is.

[0004]

When the butterfly valve is slightly opened and another valve is installed on the upstream side, or when the upstream pipe is sharply bent, fluid turbulence occurs on the upstream side. In such a case, a phenomenon may occur in which the butterfly valve is vibrated violently due to the fluid turbulence.

[0005] There is no other way to suppress the vibration except for pressing the rotary shaft of the valve. However, the fluid vibration force acts on the outer periphery of the butterfly valve. It is often difficult to hold down. The vibration directly causes undesired events such as abrasion and damage of each part.

It is an object of the present invention to provide a butterfly valve which solves the above-mentioned problems and does not generate vibration due to fluid turbulence.

[0007]

A butterfly valve according to a first aspect of the present invention is provided in a pipe and opens and closes a flow path in the pipe.
In the butterfly valve, the inner wall of the pipe (3)
A damping plate (7) made of a plate-like body and rotating while contacting the outer peripheral portion of the butterfly valve (1) is provided.

A butterfly valve according to a second aspect of the present invention is the butterfly valve according to the first aspect, wherein the inclination angle of the damping plate 7 in the radial direction of the pipe 3 is large at a position where the valve opening is small and small at a position where the valve opening is large. It is characterized by being formed in. A butterfly valve according to a third aspect of the invention is characterized in that, in the first aspect, the inclination angle of the damping plate 7 in the radial direction of the pipe 3 is constant.

[0009]

Since the vibration of the butterfly valve 1 is in a vibration mode as shown in FIG. 3, when the vibration is generated by installing the vibration damping plate 7, friction is generated between the vibration damping plate 7 and the vibration damping plate 7. do. When the damping plates 7 are installed obliquely and have a spring force, a force for pressing the butterfly valve acts, and they do not separate from each other.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment according to the present invention will be described with reference to FIG. FIG. 1 is a diagram of a butterfly valve with a damping plate according to a first embodiment. (A) is a cross-sectional view, (B) is a front view, and (C) is a perspective view showing a shape of a damping plate. A butterfly valve 1 is fixed to a rotating shaft 2 and provided in a pipe 3. Inside the pipe 3, a three-dimensionally curved damping plate 7 is installed obliquely at a position in contact with the outer periphery of the butterfly valve 1.

When the butterfly valve 1 is slightly opened, it comes into contact at the damping plate position d (FIG. 1 (C)). At this position d, the damping plate 7 is greatly inclined. The fall is getting smaller. Positions a and b are corners of the butterfly valve 1 attached to the inner wall of the pipe 3. The damping plate has a shape that can make the moment uniform at any position. Damping plate 7
Attachment is sufficient by welding or the like.

The operation of the first embodiment will be described. The damping plate 7 comes into contact with the outer periphery of the butterfly valve 1 to dampen the vibration. In addition, the butterfly valve 1 can be always rotated with a uniform force while keeping the spring constant uniform.

A second embodiment according to the present invention will be described with reference to FIG. FIG. 2 is a diagram of a butterfly valve according to a second embodiment,
(A) is a cross-sectional view, (B) is a front view, and (C) is a perspective view of a damping plate. c and d are corner positions of the damping plate 1, and a and b are corner positions of the damping plate 1 attached to the pipe 3. The inclination angle with respect to the center of the damping plate 1 is made uniform, and the damping plate 7 is formed as a flat plate and is attached obliquely.

The operation of the second embodiment will be described. When the butterfly valve 1 is slightly opened and the excitation force is large, the position d is in contact with a short portion of the length ad, so that there is an advantage that a strong spring force can be applied to the butterfly valve 1. When the valve opening increases, the flow is also rectified and the excitation force decreases, and the positions b,
Since the force approaches the distance c and defeats the long part, the spring force is weak, and a uniform vibration damping force can always be applied.

[0015]

FIG. 3 shows the vibration mode of the butterfly valve. FIG. 4 shows the results obtained by confirming the effects of the present invention by attaching the damping plate by a model test. No vibration is observed at all due to the installation of the damping plate, indicating that the damping device and method exhibit excellent effects. Therefore, wear and breakage of the butterfly valve can be prevented, and stable operation of the plant or the like can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram of a butterfly valve with a damping plate according to a first embodiment of the present invention;

FIG. 2 is a view of a butterfly valve with a damping plate according to a second embodiment of the present invention;

FIG. 3 is a diagram of a vibration mode of a butterfly valve;

FIG. 4 is a diagram showing an effect of the vibration damping plate,

FIG. 5 is a diagram of a butterfly valve according to a first conventional example;

FIG. 6 is a view of a butterfly valve according to a second conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Butterfly valve, 2 ... Rotating shaft, 3 ... Pipe, 7 ... Damping plate, a, b, c, d ... Corner position of the damping plate.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F16K 1/22 F16K 1/32 F16K 25/00

Claims (3)

(57) [Claims] 1. A pipe provided in a pipe and having a flow in the pipe.
In a butterfly valve for opening and closing a passage, the pipe (3)
Is formed of a plate-like body on the inner wall of the butterfly valve (1) .
A butterfly valve provided with a damping plate (7) that rotates while contacting an outer peripheral portion . 2. The inclination angle of the vibration damping plate (7) in the radial direction of the pipe (3) is made large at a position where the valve opening is small and small at a position where the valve opening is large. The butterfly valve according to claim 1, wherein: 3. The butterfly valve according to claim 1, wherein the inclination angle of the vibration damping plate (7) in the radial direction of the pipe (3) is constant.