JP2003254450A - Butterfly valve with water filling function - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a butterfly valve having a water filling function capable of performing a constant flow of water at a small opening.
Reduces pressure loss when the valve is fully open. SOLUTION: Disk tail portions 10a, 10b are provided on both valve body pieces 9a, 9b of a valve body 6, and both disk tail portions 10a, 10b are provided on the back side of the valve body 6 in the rotation direction at the time of opening operation. It has a spherical outer peripheral surface which is located and slidably contacts a valve box seal ring 3 provided in the valve box 2. Water holes 14 are formed in the disk tail portions 10a and 10b. In the fully closed position S, the peripheral edge of the valve element 6 slides on the valve box seal ring 3. Further, the valve body pieces 9a and 9b centered on the rotation axis 5 and the disc tail 10
Assuming that the spread angle of the valve body 6 with the a and 10b in the direction of rotation of the valve body is α °, the valve body 6 is 90 ° + α ° /
The position after two rotations is set to the fully open position O.

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a butterfly valve having a water filling function, and relates to a valve technology for supplying a fluid at a constant flow rate when filling a pipe with water. It is. 2. Description of the Related Art Conventionally, at the time of initial filling and refilling when laying a pipe, if the pipe is completely filled by rapid filling, the pipe may be damaged by a water hammer or the like. The butterfly valve provided in the pipe is opened at a small opening to fill the pipe with a small flow rate. However, it is difficult to control the flow rate of a general butterfly valve at a small opening, and it is not possible to supply a constant flow rate accurately. It was difficult to calculate the time in advance. On the other hand, as a butterfly valve for performing accurate flow rate control at a small opening degree, there is known a butterfly valve which is disclosed in Japanese Utility Model Laid-Open No. 59-101.
As disclosed in Japanese Patent Application Publication No. 054, there is a valve body provided with a spherical outer peripheral surface on a valve body disposed in a valve chamber, and a concave groove for adjusting a flow rate is formed on the valve member. [0005] However, in the above-mentioned conventional type, since a concave groove for adjusting the flow rate is formed in the valve body,
When the thickness of the valve body itself is thin, the opening area of the concave groove in the peripheral part of the valve body becomes small, the flow rate that can be adjusted becomes minute, and the opening shape of the concave groove is a shape in which the peripheral part of the valve body is cut off. Therefore, there is a problem that the flow rate changes due to a slight change in the opening degree. An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a butterfly valve having a water filling function capable of supplying a constant flow of water at a small opening. [0007] In order to achieve the above object, the present invention provides a valve case in which a valve case seal ring is provided in an annular shape along an inner peripheral surface in a valve case, and a flow through the valve case is provided. An openable and closable valve element that rotates about a rotation axis orthogonal to the road axis is provided in the valve box via a valve stem, and the valve element is provided with a boss through which the valve stem is inserted, and on both sides of the boss. A disc-tail portion formed in a disk shape with a pair of provided semi-disc-shaped valve body pieces is provided on each of the two valve body pieces. The part is located on the back side of the valve body in the rotation direction at the time of the opening operation, and has a spherically curved outer peripheral surface that is in sliding contact with the valve box seal ring. Is opened to the outer peripheral surface and the other end is opened to the back side of the valve body. A hole is formed, and in the fully closed position, the peripheral edge of the valve body slides on the valve box seal ring, and the angle of spread of the valve body piece and the disk tail portion around the rotation axis in the valve body rotation direction. Is set to α °, a position where the valve element is rotated by 90 ° + α ° / 2 from the fully closed position in the opening direction to the opening direction is set to a fully open position, and in the fully open position, the flow axis of the valve element piece and the disk tail portion is set. The maximum projection width in the direction is formed to be larger than the outer diameter of the boss. According to this, the valve body is opened to a small opening degree by the opening operation, and the water holes are fully opened in a state where the outer peripheral surfaces of both disc tail portions are in sliding contact with the valve box seal ring. . This ensures that the water hole is fully open in the predetermined rotation range of the valve body in which the outer peripheral surfaces of both disc tail portions are kept in sliding contact with the valve box seal ring. The upstream area and the downstream area in the valve box through the valve body communicate only through the water hole, depending on the fully opened state of the water hole at the small opening degree of the valve body as described above. The water (fluid) flowing into the valve box from the pipe (1) passes through the water hole to the downstream pipe. [0010] Since the flow rate through the water flow hole is predetermined according to the shape of the flow path of the water flow hole, water can be supplied to the downstream pipe at a constant flow rate, and the pipe is fully filled from the start of water supply. The required time (required time) until becomes can be accurately calculated in advance. When the valve body is rotated to the fully open position by the plugging operation after the pipe is filled as described above, the maximum amount of water (fluid) flows from the upstream side to the downstream side of the valve body. At this time, the valve body is 90 ° +
Since the position rotated by α ° / 2 is set as the fully open position, the projected area of the valve element and the disc tail in the direction of the flow axis (ie, the projected area viewed from the direction of the flow axis) is the minimum. Therefore, the pressure loss when the valve element is fully opened can be reduced. Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 to 6, reference numeral 1 denotes a butterfly valve, and a valve box 2 has an upstream pipe (not shown) and a downstream pipe (not shown) connected to ports (not shown) on both sides. I have. In the valve case 2, an annular valve case seal ring 3 is provided along the inner peripheral surface. An openable and closable valve element 6 that rotates about a rotation axis 5 orthogonal to a flow path axis 4 that passes through the valve box 2 is provided in the valve box 2 via a valve rod 7. The valve element 6 is formed in a disk shape by a cylindrical boss 8 disposed in the center and a pair of semi-disc-shaped valve element pieces 9a and 9b provided on both sides of the boss 8. Have been. The valve stem 7 is inserted into the boss 8 and integrally connected thereto, and is rotatably held by the valve box 2. Disk tail portions 10a, 10b formed in a fan shape around the rotation axis 5 are attached and fixed to the two valve body pieces 9a, 9b via a plurality of bolts 11, 12, respectively. The two disk tail portions 10a,
10b is a rotation direction at the time of opening operation (opening direction).
Are located on the back side of the valve element 6 and the valve element pieces 9a,
A tail part 13 having a predetermined thickness rising from the peripheral part of 9b.
And the outer peripheral surface of the tail portion 13 is curved in a spherical shape in sliding contact with the valve box seal ring 3. Each of the tail portions 13 of the disk tail portions 10a and 10b has an elongated oval water passage hole 14 formed in the direction of the rotation axis 5. One end of each of the water holes 14 is opened on the outer peripheral surface of the tail portion 13, and the other end is opened on the inner peripheral surface of the tail portion 13, that is, on the back side of the valve element 6 at the time of the opening operation. One of the disc tail portions 10 provided on one of the valve element pieces 9a which rotates downstream during the opening operation.
The opening 14 on the back side of the valve body 6 has an inflow port 14a.
a, and the opening on the outer peripheral surface side of the tail portion 13
b. In addition, the water passage hole 14 of the other disc tail portion 10b provided on the other valve body piece 9b that rotates to the upstream side during the opening operation is formed by the opening on the outer peripheral surface side of the tail portion 13 being the inflow port 1.
4c, and the opening on the back side of the valve element 6 becomes the outflow port 14d. As shown in FIGS. 1 and 2, at the fully closed position S, the peripheral portion of the valve element 6 slides on the valve box seal ring 3 so that the upstream and downstream sides of the valve element 6 are watertight. In this case, both front and back surfaces of the valve element pieces 9a and 9b are orthogonal to the flow path axis 4. Further, as shown in FIG. 3, when the valve body 6 is opened from the fully closed position S by a small opening A, the end portions of the outer peripheral surfaces of the disk tail portions 10a and 10b on the side opposite to the valve body are sealed by a valve box seal. It is configured as a seal portion 15 that slides on the ring 3. Further, as shown in FIG.
One of the valve element pieces 9a and the disk tail portion 10
The angle of spread of the valve body 6 in the direction of rotation of the valve body is α °, and the angle of spread of the other valve element piece 9b and the disk tail portion 10b in the direction of rotation of the valve body is also α °. A predetermined angle B ° (= 90 ° + α) from the fully closed position S to the opening direction
The position rotated by (° / 2) is set to the fully open position O. The divergence angle α ° is defined by each of the valve element pieces 9a and 9b.
From the center in the thickness direction to the end of the tail portion 13 on the side opposite the valve body. In the fully open position O, the maximum of one valve element piece 9a and one disk tail part 10a (or the other valve element piece 9b and the other disk tail part 10b) in the direction of the flow axis 4 is obtained. The projection width W is formed larger than the outer diameter D of the boss 8 (W> D). The end of the valve rod 7 is connected to a driving device (not shown) that opens and closes the valve element 6 by rotating the valve rod 7. Further, the butterfly valve 1 is provided with a position detecting device (a limit switch, a pulse encoder, etc .: not shown) for detecting the fully closed position S, the fully open position O, and the position of the small opening A of the valve body 6 respectively. ing. The operation of the above configuration will be described below.
At the beginning of the operation at the time of initial water filling and the time of refilling when laying the pipe, the valve element 6 is in the fully closed position S as shown in FIGS.
, The peripheral portion of the valve body 6 is in sliding contact with the valve box seal ring 3 so that the upstream side and the downstream side of the valve body 6 are sealed in a watertight manner. Then, in order to prevent the piping from being damaged by sudden water filling, as shown in FIG. 3, the butterfly valve 1 is opened to a small opening degree A, and the downstream piping is filled with a small flow rate. That is, when the valve body 6 is opened to a small opening degree A by the opening operation, the two disk tail portions 10a and 10b are opened.
The outer peripheral surface of the seal portion 15 is in sliding contact with the valve box seal ring 3, and in this state, both water passage holes 14 are fully opened. At this time, in the predetermined rotation range of the valve element 6 in which the outer peripheral surface of the seal portion 15 can be kept in sliding contact with the valve box seal ring 3, the fully open state of both water holes 14 is stably maintained. You. Depending on the fully opened state of the two water holes 14 at the small opening degree A of the valve body 6 as described above, the valve box 2 through the valve body 6
The upstream region and the downstream region communicate with each other only through the two water holes 14, and water (fluid) flowing into the valve box 2 from the upstream pipe passes through the two water holes 14 to the downstream pipe. Water is passed. At this time, since the flow rate flowing through the two water holes 14 is predetermined according to the flow path shape such as the flow path cross-sectional area of the water holes 14, the downstream pipe is filled with a constant flow rate. It is possible to accurately calculate the required time (required time) from the start of water filling to the full state in advance. After the pipe is filled as described above and the valve body 6 is further rotated to the fully open position O by the opening operation as shown in FIG. 4, the maximum amount of water (fluid)
Flows from the upstream side of the valve body 6 to the downstream side in the valve box 2. At this time, the valve body 6 is moved from the fully closed position S to the opening direction by a predetermined angle B °.
Since the position rotated (= 90 ° + α ° / 2) is set as the fully open position O, as shown in FIG. 8 (a), the flow path axis where the valve body 6 and the disk tail portions 10a and 10b are combined. The projected area E1 in the four directions (that is, the projected area viewed from the four directions of the flow axis) is minimized, and therefore, the pressure loss when the valve is fully opened can be reduced. As described above, in the present invention, as shown in FIG. 4, the predetermined angle B ° = 90 ° +
Although the position rotated by α ° / 2 is set to the fully open position O, if the position rotated by a predetermined angle B ° = 90 ° is set to the fully open position O as shown in FIG. FIG.
As shown in (b), the valve body 6 and the disc tail 10a,
10b and the projected area E in the direction of the flow channel axis 4
2 (that is, the projected area viewed from the direction of the flow channel axis 4) becomes larger than the projected area E1 (E2> E1), and there is a problem that the pressure loss when the valve body is fully opened increases. FIG. 9 is a graph showing the relationship between the opening degree (rotation angle) of the valve element 6 of the butterfly valve 1 and the pressure loss coefficient. This corresponds to three types of butterfly valves 1 having different areas. Further, the opening degree of the valve element 6 = 0 ° corresponds to the fully closed position S shown in FIG. 1, and the opening degree B ° (= 90 ° + α ° / 2) corresponds to FIG.
Corresponds to the fully open position O shown in FIG. According to the above graph, as the opening of the valve body 6 increases, the pressure loss coefficient of the butterfly valve 1 of each type T1, T2, T3 decreases, and even if the opening exceeds 90 °, the pressure loss coefficient increases. Continue to decrease, and the pressure loss coefficient becomes minimum at the opening degree B ° (ie, the fully open position O in FIG. 4). In the above embodiment, as shown in FIG.
The inlets 14a, 14c and the outlets 14b of each water passage hole 14,
The water passage hole 14 is formed in a straight shape with the same size as that of the water passage hole 14d. It may be formed. With such a tapered shape, cavitation due to flowing water (fluid) passing through the water passage hole 14 can be suppressed. In the above embodiment, the water passage holes 14 are formed in both the disk tail portions 10a and 10b, but the other disk tail portion 10b that rotates to the upstream side during the opening operation is opened.
The water passage hole 14 may be formed only in the disk tail portion 10a that is turned to the downstream side during the opening operation. In the above embodiment, as shown in FIG.
The water passage hole 14 is formed in an oval shape.
For example, it may be formed in a polygonal shape or a perfect circle shape. Also,
Although one water passage hole 14 is formed in each of the disk tail portions 10a and 10b, a plurality of small circular water passage holes 14 may be formed. In the above embodiment, the disk tails 10a and 10b are separate members from the valve body 6.
The disk tail portions 10a and 10b may be formed integrally with the valve body 6. Furthermore, in order to reduce the resistance of the tail portion 13 when the valve body 6 is fully opened, the disk tail portion 10
The a and 10b may have a thick plate shape in which the rear surface forms a flat surface. In the above embodiment, water is used as an example of the fluid flowing through the butterfly valve 1. However, a liquid or gas other than water may flow. As described above, according to the present invention, when the valve body is opened to a small opening, the valve that maintains the outer peripheral surfaces of both disc tail portions in sliding contact with the valve box seal ring is maintained. In the predetermined rotation range of the body, the fully opened state of the water hole is stably maintained. Due to such a fully opened state of the water hole, the upstream area and the downstream area in the valve box via the valve body communicate only through the water hole, and the flow rate flowing through the water hole is the flow path shape of the water hole. Since it is predetermined in advance, it is possible to fill the downstream pipe with a constant flow rate, and it is possible to accurately calculate in advance the required time (required time) from the start of filling to the full state. it can. When the valve is rotated to the fully open position by the opening operation after the pipe is filled, the maximum amount of water (fluid) flows from the upstream side to the downstream side of the valve body. On this occasion,
Since the position at which the valve element is rotated 90 ° + α ° / 2 from the fully closed position in the opening direction is set as the fully open position, the projected area of the valve element and the disc tail in the direction of the axis of the flow path (that is, the projected area) (Projected area viewed from the flow channel axis direction) is minimized, thereby reducing pressure loss when the valve body is fully opened.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view of a butterfly valve according to an embodiment of the present invention, showing a state where a valve body is in a fully closed position. FIG. 2 is a cross-sectional view of the butterfly valve, showing a state where a valve body is at a fully closed position. FIG. 3 is a sectional view of the butterfly valve, showing a state where the valve body is opened by a small opening degree. FIG. 4 is a view of the butterfly valve, showing a state where the valve body is in a fully open position. FIG. 5 is a view taken in the direction of arrows XX in FIG. 1; FIG. 6 is a view taken in the direction of arrows Y in FIG. 1; FIG. 7 is a view of the butterfly valve, showing a state where the valve body is opened by 90 °. FIG. 8 is a view showing a projected area of the butterfly valve,
(A) is when the fully open position = 90 ° + α ° / 2,
(B) is a case where the full open position is 90 °. FIG. 9 is a graph showing the relationship between the valve body opening of the butterfly valve and the pressure loss coefficient. [Description of Signs] 1 Butterfly valve 2 Valve box 3 Valve box seal ring 4 Flow axis 5 Rotation axis 6 Valve 7 Valve rod 8 Boss 9a, 9b Valve piece 10a, 10b Disc tail 14 Water passage hole S Fully closed position O Fully open position W Maximum projection width D Outer diameter α of boss Spread angle

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Masaaki Kitamura             1-1-1 Nakamiya Oike, Hirakata City, Osaka Prefecture             The formula company Kubota Hirakata Factory (72) Inventor Akira Nobuura             1-1-1 Nakamiya Oike, Hirakata City, Osaka Prefecture             The formula company Kubota Hirakata Factory F-term (reference) 3H052 AA02 BA03 CA11 DA02 EA02                 3H066 AA02 BA01 BA38 EA33

Claims (1)

Claims: 1. A valve box seal ring is provided in an annular shape along an inner peripheral surface in a valve box, and rotates around a rotation axis orthogonal to a flow path axis passing through the valve box. An openable and closable valve element is provided in a valve box via a valve rod, and the valve element has a boss portion through which the valve rod is inserted, and a pair of semi-disc-shaped valve elements provided on both sides of the boss portion. The two valve body pieces are each provided with a disk tail portion formed in a fan shape around the rotation axis, and the two disk tail portions are provided with a valve in the rotation direction at the time of the opening operation. An outer peripheral surface that is located on the back side of the body and that is spherically curved and is in sliding contact with the valve box seal ring; A water passage opening is formed on the back side of the valve body. Is slidably in contact with the valve box seal ring, and the divergence angle of the valve body piece and the disk tail portion in the valve body rotation direction about the rotation axis is α °, and the valve body is opened from the fully closed position. The position that is rotated 90 ° + α ° / 2 in the direction is set to the fully open position, and in the fully open position, the maximum projection width of the valve element piece and the disk tail portion in the direction of the flow axis is larger than the outer diameter of the boss portion. A butterfly valve provided with a water filling function.