JPH07208615A - Back-washable nozzle valve - Google Patents

Abstract

PURPOSE:To easily eliminate clogging even if a nozzle is clogged, so as to restrain anti-cavitation performance from being deteriorated by providing many small holes through which fluid passes on a blade body wherein a flow adjusting means is bent in a spherical form. CONSTITUTION:A nozzle valve 1 is in a butterfly valve-like form, and a valve body 2 opens and closes a valve box inside passage 4 formed in a valve box 3. The valve body 2 is so provided as to be normally and reversely rotated around a shaft center of a valve shaft 5 by 18 deg.. In the valve body 2, the flow adjusting means 6 for adjusting the passing flow rate of fluid is provided on the front surface side on one side of the valve body 2 and on the back surface side on the other side of the valve body 2 within the suitable opening range, and this flow adjusting means 6 has a structure wherein many small holes 8 through which fluid passes are provided on a spherically bent blade 7. Accordingly, foreign matters clogging the small holes can be washed away by reversely rotating the valve body around the shaft center of the valve shaft, and reversing the flow of fluid in small holes of the blade body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backwashable nozzle valve used in waterworks, agricultural water, sewer pipelines, etc., to control the flow rate of fluid.

[0002]

2. Description of the Related Art Conventionally, as a valve for controlling the flow rate of a fluid in water supply, agricultural water, sewer pipelines, etc.,
There are butterfly valves, perforated variable orifice valves and butterfly valves with nozzles.

A butterfly valve is suitable for a small amount of pressure reduction, but has a limit to its limitation because cavitation occurs when the amount of pressure reduction is large. A multi-perforated variable orifice valve is useful for high pressure reduction. In the multi-perforated variable orifice valve, the movable valve element and the fixed valve element are arranged in parallel, and the movable valve element is extended and retracted along the plate surface of the fixed valve element so that the orifice holes formed in both valve elements are aligned or displaced. The flow rate is controlled. However, in the perforated variable orifice valve, if the water quality is poor, there is a problem that the orifice hole is clogged with foreign matter contained in the running water.

A butterfly valve with a nozzle is provided with a blade body having a plurality of nozzle holes at a peripheral portion of a valve body, water is passed through the nozzle hole at an intermediate opening of the valve body, and is opened by opening and closing of the valve body. The flow rate is controlled by adjusting the number of holes.

[0005]

However, in the above-mentioned conventional butterfly valve with nozzle, when the nozzle hole is clogged, there is a problem that the structure is vulnerable to cavitation characteristically like the butterfly valve.

The present invention solves the above problems, and can be easily removed even if the nozzle is clogged.
An object of the present invention is to provide a backwashable nozzle valve that does not deteriorate cavitation resistance performance.

[0007]

In order to solve the above-mentioned problems, the backwashable nozzle valve of the present invention has a valve body which opens and closes a flow path in the valve box in the valve box around the axis of the valve shaft. It is provided rotatably over 180 degrees in the forward and reverse directions, and the flow rate of fluid is adjusted on the front side of one side of the valve body and the back side of the other side of the valve body with the valve shaft as a boundary within an appropriate opening range of the valve body. The flow rate adjusting means is provided, and the flow rate adjusting means has a configuration in which a large number of small holes for fluid passage are provided in the blade body curved in a spherical shape.

[0008]

With the above-described structure, the valve body rotates about the axis of the valve shaft during opening, one side of the valve body rotates in the forward direction of the fluid flow, and the other side of the valve body reverses the fluid flow. Rotate in the direction. At this time, within the appropriate opening range of the valve body, the fluid passes through a large number of small holes of the blade body forming the flow rate adjusting means, and the number of small holes in the open state increases or decreases as the valve body opens and closes. To control the flow rate.

When a foreign substance in the fluid is clogged in the small hole, the valve body is inverted around the axis of the valve shaft so that the back surface of the valve body faces the fluid. In this state, the flow of the fluid in the small holes of the blade body is reversed, and the fluid flushes the foreign matter clogged in the small holes.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, a nozzle valve 1 has a form like a butterfly valve, and a valve body 2 opens and closes a flow path 4 in a valve box formed inside a valve box 3. The valve body 2 is rotatably provided around the axis of the valve shaft 5 in the forward and reverse directions of 180 °. In the valve body 2, the flow rate of the fluid is adjusted on the front side of the valve body 2 on one side of the valve shaft 5 and the rear side of the other side of the valve body 2 within an appropriate opening range of the valve body 2. A flow rate adjusting means 6 is provided,
The flow rate adjusting means 6 has a structure in which a large number of small holes 8 for passage of fluid are provided in a wing body 7 curved in a spherical shape.

The operation of the above structure will be described below.
As shown in FIG. 2, at the time of opening, the valve body 2 rotates in the positive direction A around the axis of the valve shaft, and the one side 2a of the valve body 2 becomes the fluid 9
And the other side 2b of the valve body 2 rotates in the opposite direction of the fluid flow. At this time, within the appropriate opening range of the valve body 2, a large number of small holes 8 of the blade body 7 forming the flow rate adjusting means 6 are formed.
The flow rate is controlled by the passage of the fluid 9 and the increase / decrease in the number of the small holes 8 in the open state as the valve body 2 opens and closes.

If the small hole 8 is clogged with foreign matter in the fluid 9, the valve body 2 is inverted around the axis of the valve shaft 5 as shown in FIG. Face the fluid 9. In this state, the flow of the fluid 9 in the small holes 8 of the blade body 7 reverses, and the fluid 9 flushes the foreign substances clogged in the small holes 8.

[0013]

As described above, according to the present invention, by reversing the valve body around the axis of the valve shaft, the flow of fluid in the small holes of the blade body is reversed and the foreign matter clogged in the small holes. Can be washed away.

[Brief description of drawings]

FIG. 1 is a partially broken cross-sectional view showing a backwashable nozzle valve according to an embodiment of the present invention.

FIG. 2 is a partially broken cross-sectional view showing the action when the backwashable nozzle valve is opened in the embodiment.

FIG. 3 is a partially broken cross-sectional view showing the action of the backwashable nozzle valve in the same embodiment at the time of backwashing.

[Explanation of symbols]

 1 Backwashable nozzle valve 2 Valve body 3 Valve box 4 Flow path inside valve box 5 Valve shaft 6 Flow rate adjusting means 7 Blade body 8 Small hole 9 Fluid

Claims (1)

[Claims] 1. A valve body for opening and closing a flow path in the valve box is provided rotatably around the axis of the valve shaft in the forward and reverse directions by 180 °, and a surface of the valve body on one side with the valve shaft as a boundary. Side and the back side of the other side of the valve body are provided with flow rate adjusting means for adjusting the flow rate of the fluid passing within an appropriate opening range of the valve body, and the flow rate adjusting means is provided with a large number of fluid passages on the blade body curved in a spherical shape. A nozzle valve capable of backwashing, which is characterized in that it has a small hole.