JPH0723868U - Butterfly valve - Google Patents

Abstract

(57) [Summary] [Structure] The valve body 3 is provided eccentrically from the valve shaft 4 in the valve box 1, and the fluid passage prevention wall 6 is provided on one side 3a of the valve body 3.
On the other side 3b of the valve body 3, a spherically curved wing body 7 is provided.
The blade body 7 was provided with a large number of small holes 8 for passage of fluid. [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 side 3b of the valve body 3, and the small hole 8 of the blade body 7 is formed.
The flow rate area can be increased or decreased by adjusting the number of the flow paths to perform accurate flow rate control. Further, the fluid is jetted from the outer peripheral surface side of the blade body 7 which is curved in a spherical shape toward the center of the flow passage 2 in the valve box, thereby damaging the inner wall surface of the valve box 1 due to the jet flow ejected from the small holes 8. It can be prevented.

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 opens and closes a flow path in the valve box by rotating around the axis of the valve shaft in the valve box and displaces the valve shaft from the center of the valve body. It is installed with the center in mind, and a fluid passage prevention device is provided on the front surface of one side of the valve body with the center of the valve body as a boundary to prevent the passage of the fluid within the appropriate opening range of the valve body, and on the back surface of the other side of the valve body. A structure is provided in which a flow rate adjusting means for adjusting the flow rate of the fluid passing is provided within an appropriate opening range of the valve body, and a large number of small holes for fluid passage are provided in the blade body in which the flow rate adjusting means is curved in a spherical shape. Is.

[0006]

With the above-described configuration, the valve body rotates about the axis of the valve shaft when the valve is opened, and one side of the valve body having the fluid passage prevention unit rotates in the forward direction of the fluid flow, and the flow rate adjusting unit operates. The other side of the existing valve body rotates in the direction opposite to the flow of the fluid, and the one side flow path opens around the one side of the valve body, while the other side flow path opens around the other side of the valve body. Open.

At this time, since the center of the valve body of the valve body is eccentric with respect to the axial center of the valve shaft, the peripheral portion of the valve body on one side is separated from the inner wall surface of the valve box by a distance larger than that of the valve body. The distance that the peripheral portion on the other side separates 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 the passage of the fluid through the one side passage of the valve body passage. Most of the fluid flowing through the inner flow path flows through the other side flow path corresponding to the other side of the valve body, and then flows downstream through the small holes of the blade body of the flow rate adjusting means.

Therefore, by adjusting the number of small holes through which the fluid passes by rotating the valve body to increase or decrease the flow passage area, it is possible to perform accurate flow rate control. Moreover, as the fluid passes through the small holes, it flows from the outer peripheral surface of the spherically curved vane toward the center of the flow path in the valve box, so the inner wall surface of the valve box is exposed to the jet flow ejected from the small holes. Therefore, the inner wall surface of the valve box is not damaged by the jet flow.

[0010]

【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 front surface of the one side 3a with the center of the valve body 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.

On the back surface of the other side 3b of the valve body 3, a blade body 7 forming a flow rate adjusting means is integrally formed, and the blade body 7 is curved in a spherical shape centered on the axis of the valve shaft 4. , Has a plurality of small holes 8 through which the fluid passes. Therefore, within the appropriate opening range of the valve body 3, the fluid passes through the small holes 8 of the blade body 7 to the downstream side, and the number of the small holes 8 through which the fluid passes as the valve body 3 opens. The flow path area gradually increases.

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

At this time, since the center of the valve body of the valve body 3 is eccentric with respect to the axis of the valve shaft 4, the peripheral portion 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 the 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 through the flow path 2 inside the valve box flows through the other side flow path corresponding to the other side 3 b of the valve body 3 and flows through the small holes 8 of the blade body 7 to the downstream side.

Therefore, by adjusting the number of the small holes 8 through which the fluid passes by the rotation of the valve body 3 and increasing or decreasing the flow passage area, it is possible to perform an accurate flow rate control. Moreover, when the fluid passes through the small hole 8, it flows from the outer peripheral surface side of the blade body 7 which is curved in a spherical shape toward the center of the flow path 2 in the valve box, so that the inner wall surface of the valve box 1 is removed from the small hole 8. The inner wall surface of the valve box 1 is not damaged by the jet flow because it is not exposed to the jet flow.

[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 path in the valve box can be guided to the other side flow path corresponding to the other side of the valve body, and the flow path area can be adjusted by adjusting the number of small holes in the blade body. It is possible to control the flow rate accurately by increasing or decreasing. Further, by causing the fluid to jet from the outer peripheral surface side of the blade body that is curved spherically toward the center of the flow passage in the valve box, it is possible to prevent damage to the inner wall surface of the valve box due to the jet flow emitted from the small holes.

[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 perspective view of a valve body in the same embodiment.

[Explanation of symbols]

 1 valve box 2 flow path in valve box 3 valve body 6 fluid passage prevention wall 7 wing body 8 small hole

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. A fluid passage prevention means for preventing passage of fluid within the appropriate opening range of the valve body is provided on the front surface of one side of the valve body as a boundary, and within the appropriate opening range of the valve body on the back side of the other side of the valve body. A butterfly valve comprising a flow rate adjusting means for adjusting a flow rate of a fluid, wherein the flow rate adjusting means is provided with a large number of small holes for passing the fluid in a blade body curved in a spherical shape.