JPH0723867U - Butterfly valve - Google Patents

Abstract

(57) [Summary] [Structure] The valve body 3 disposed in the valve box 1 is provided eccentrically from the axis of the valve shaft 4, and a fluid passage prevention wall body 6 is provided on the back surface of the one side 3a of the valve body 3. The valve body 1 is provided with a flow rate adjusting means 7 located on the back surface of the other side 3b of the valve body 3, and the flow rate adjusting means 7 supports the blade body 8 surrounding the peripheral portion of the valve body 3 and the blade body 8 to support the valve. Box 1
A wall protector 9 to be fitted on the inner wall surface of No. 1 was provided, and a plurality of small holes 10 whose flow passage area gradually increased as the valve body 3 was opened were formed in the blade 8. [Effect] Most of the fluid flowing through the flow path 2 in the valve box is guided to the other side flow path corresponding to the other one side 3 b of the valve body 3, and it is more appropriate by increasing or decreasing the small holes 10 of the blade body 8 of the flow rate adjusting means 7. It is possible to perform various flow rate control. In addition, the wall protector 9 allows the small hole 10 to be formed.
It is possible to prevent damage to the inner wall surface of the valve box 1 due to the jet flow ejected from the.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a butterfly valve used for controlling the flow rate of water.

[0002]

[Prior art]

 Conventional butterfly valves include those described in, for example, Japanese Utility Model Laid-Open No. 62-6568 and Japanese Patent Laid-Open No. 57-15866, and in these, as means for absorbing fluid energy in the butterfly valve, Wings are provided around the valve body, a large number of small holes are formed in the blade, and tooth-shaped ribs are provided around the valve body.

[0003]

[Problems to be solved by the device]

 However, the above-mentioned conventional structure is mainly aimed at low noise and low torque, but when the flow rate is controlled at a small opening, the jet flow ejected from many small holes of the blade provided on the valve body causes the inner wall surface of the valve box to be reduced. Had the problem of being damaged.

The present invention solves the above problems, and an object of the present invention is to provide a butterfly valve capable of preventing damage to the inner wall surface of a valve box due to a jet flow ejected from a small hole.

[0005]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the present invention arranges a valve body that rotates around the axis of the valve shaft to open and close the flow passage in the valve box in the valve box, and eccentric the valve shaft from the center of the valve box. Provided on the rear surface of one side of the valve body with the center of the valve body as a boundary is a fluid passage prevention means for preventing passage of fluid within the appropriate opening range of the valve body, and the rear side of the other side of the valve body in the valve box. Is provided with a flow rate adjusting means, and the flow rate adjusting means supports the wing body surrounding the rim of the valve body within an appropriate opening range of the valve body and a wall surface which is fitted into the inner wall surface of the valve box by supporting the wing body. A protective body is provided, and a fluid passage hole is formed in the blade body in which the flow passage area gradually increases as the valve body opens.

[0006]

[Action]

 With the above structure, the valve body rotates around the axis of the valve shaft when opened, and one side of the valve body having the fluid passage prevention means rotates in the direction opposite to the flow of the fluid, and has the flow rate adjusting means. The other side of the valve body rotates in the forward direction of the fluid flow, and the one side flow path opens around the one side of the valve body, and the other side flow path opens around the other side of the valve body. At this time, the center of the valve body of the valve body is eccentric with respect to the axial center of the valve shaft, so that the peripheral edge of one side of the valve body is more distant from the inner wall surface of the valve box than the other side of the valve body. The distance that the peripheral edge is separated from the inner wall surface of the valve box becomes larger, and the other side flow passage opens larger than the one side flow passage.

On the other hand, within the appropriate opening range of the valve body, the fluid passage preventing means provided on one side of the valve body prevents passage of the fluid through the one side passage of the valve body passage, so that the valve body Most of the fluid flowing in the inner flow path flows in the other side flow path corresponding to the other one side of the valve body, and flows downstream through the passage hole of the blade body of the flow rate adjusting means. Therefore, the flow rate can be controlled appropriately by increasing or decreasing the flow passage area in the passage hole by rotating the valve body.

Moreover, since the wall surface protector covers the inner wall surface of the valve box, the inner wall surface of the valve box is not damaged by the jet flow ejected from the passage hole.

[0009]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. 1 and 2, a valve body 3 that opens and closes a flow path 2 in the valve body is provided inside the valve body 1 so as to be rotatable around the axis of a valve shaft 4. It is eccentric from the center. The inner wall surface of the valve box 1 is provided with a valve box seal 5 that abuts the peripheral edge of the valve body 3 in a fully closed state.

The valve body 3 is integrally formed with a fluid passage prevention wall portion 6 forming a fluid passage prevention means on the back surface of the one side 3a with the valve body center as a boundary. The outer peripheral surface is curved in a spherical shape centered on the axis of the valve shaft 4. Therefore, within the appropriate opening range of the valve element 3, the fluid passage prevention wall portion 6 always maintains a constant gap between the outer peripheral surface thereof and the valve box seal 5 to prevent passage of fluid.

A flow rate adjusting means 7 is provided inside the valve box 1 on the back surface of the other side 3 b of the valve body 3, and the flow rate adjusting means 7 integrally includes a blade body 8 and a wall surface protective body 9. Molded and made of cavitation resistant material such as stainless steel. The blade body 8 is curved in a spherical shape so as to surround the peripheral edge portion of the valve body 3 within an appropriate opening range of the valve body 3, and the wall surface protective body 9 is arcuate so as to be fitted into the inner wall surface of the valve box 1. Is curved. Further, the blade body 8 is provided with a plurality of small holes 10 as passage holes through which the fluid passes, and the number of the small holes 10 through which the fluid passes increases as the valve body 3 opens, and the passage of the passage holes is increased. The area gradually increases.

The operation of the above configuration will be described below. At the time of opening, the valve body 3 rotates about the axis of the valve shaft 4, and the one side 3a of the valve body 3 having the fluid passage prevention wall 6 rotates in the opposite direction of the fluid flow, and the flow rate adjusting means 7 Since the other side 3b of the valve body 3 having the valve body rotates in the forward direction of the fluid flow, the one side flow path is opened in the valve box 1 around the one side 3a of the valve body 3 and the valve body 3 The other side flow path opens around the other side 3b.

At this time, the center of the valve body of the valve body 3 is eccentric with respect to the axis of the valve shaft 4, so that the peripheral edge of the one side 3 a of the valve body 3 is separated from the inner wall surface of the valve box 1. Compared with this, the distance at which the peripheral portion of the other side 3b of the valve body 3 is separated from the inner wall surface of the valve box 1 becomes larger, and the other side flow passage opens larger than the one side flow passage.

On the other hand, within the appropriate opening range of the valve body 3, the fluid passage prevention wall body 6 provided on one side 3 a of the valve body 3 prevents passage of the fluid in the one side passage of the valve box passage 2. Therefore, most of the fluid flowing in the flow path 2 in the valve box flows in the other side flow path corresponding to the other one side 3 b of the valve body 3, and flows to the downstream side through each small hole 10 of the blade body 8. Therefore, by adjusting the number of the small holes 10 through which the fluid passes by rotating the valve body 3 and increasing or decreasing the flow passage area in the passing holes, it is possible to perform accurate flow rate control.

Moreover, since the fluid that has passed through the small holes 10 is ejected toward the wall protector 9 that covers the inner wall surface of the valve box 1, the inner wall surface of the valve box 1 is No damage. Further, since the flow rate adjusting means 7 is made of a cavitation resistant material such as stainless steel, it is less damaged by the jet flow and can be easily replaced even if it is damaged.

As shown in FIG. 3, the flow rate adjusting means 7 may be formed by providing the blade body 8 with a V-shaped cut opening 11, and the flow passage area at the cut opening 11 is equal to that of the valve body 3. The flow rate can be controlled by gradually increasing with opening. Other functions and effects are similar to those of the previous embodiment.

[0017]

[Effect of device]

 As described above, according to the present invention, the valve body is eccentrically arranged with respect to the valve shaft, and the passage of the fluid in the one side passage of the flow passage in the valve box is achieved by the fluid passage preventing means provided on one side of the valve body. By preventing this, most of the fluid flowing in the flow passage in the valve box can be guided to the other side flow passage corresponding to the other side of the valve body, and the flow passage area of the passage hole of the blade of the flow rate adjusting means can be reduced. An accurate flow rate control can be performed by increasing or decreasing. Further, the wall protector can prevent the inner wall surface of the valve box from being damaged by the jet flow ejected from the passage hole.

[Brief description of drawings]

FIG. 1 is a sectional view of a butterfly valve showing an embodiment of the present invention.

FIG. 2 is a front view of a flow rate adjusting means in the embodiment.

FIG. 3 is a front view of a flow rate adjusting means according to another embodiment of the present invention.

[Explanation of symbols]

 1 valve box 2 flow path in valve box 3 valve body 6 fluid passage prevention wall body 7 flow rate adjusting means 8 blade body 9 wall surface protector

Claims (1)

[Scope of utility model registration request] 1. A valve body is provided in a valve box for rotating around a shaft center of a valve shaft to open and close a flow path in the valve box, and the valve shaft is provided eccentrically from a center of the valve body. Provided on the rear surface of one side of the valve body as a boundary is a fluid passage prevention means for preventing passage of fluid within the appropriate opening range of the valve body, and is located on the rear surface of the other side of the valve body to adjust the flow rate. Means and the flow rate adjusting means is provided with a wing body surrounding the peripheral edge portion of the valve body within an appropriate opening range of the valve body and a wall surface protector that supports the wing body and is fitted into the inner wall surface of the valve box. A butterfly valve characterized in that a fluid passage hole is formed in which a flow passage area gradually increases as the valve body opens.