JPS6323661Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a check valve, and particularly to a ball-type check valve that opens and closes a flow path using a ball.

[Prior Art] Fig. 1 shows an example of a conventional ball type check valve, in which 1 is a valve body with a liquid inlet 1a and an outlet 1.
It is equipped with b. 2 is a ball which, when the pump is stopped and no liquid is flowing, moves to the solid line due to its own weight and blocks the inlet 1a, and when the pump is activated and liquid flows, it moves to the chain line position due to the liquid pressure, and the ball moves to the position indicated by the chain line, and the ball 2 blocks the inlet 1a. is opened, and the liquid flows from the inlet 1a to the outlet 1b. Reference numeral 3 denotes a lid that is opened to clean the inside 1c of the valve body 1c when the inside 1c of the valve body 1 is clogged with foreign matter, and 4 is a bolt that fixes the lid 3 to the valve body 1.

By the way, when such a conventional check valve is used especially for filth, there are many foreign substances such as fibers mixed into the inflow liquid, and large foreign substances are also contained, so it is necessary to enlarge the passage. For this reason, when the pump connected to the check valve is stopped, it takes a long time to close the valve, resulting in a disadvantage that water hammer is likely to occur.

[Purpose of the invention] The present invention aims to eliminate the above-mentioned drawbacks of the conventional ball-type check valve, and to provide a check valve that can shorten the valve closing time when the pump is stopped and prevent the occurrence of water hammer. It was done for a purpose.

[Structure of the invention] Therefore, according to the invention, in a ball-type check valve equipped with a ball that floats up by liquid pressure to open a flow path and closes the flow path by its own weight, a ball moving part inside the valve body is provided with a ball moving part inside the valve body. A check valve is provided in which an elastic member is provided on the side surface of a fluid flow path, and is compressed when a ball floating due to liquid pressure comes into contact with the ball, and when the liquid pressure acting on the ball is removed, expands and pushes the ball.

[Operation of the invention and preferred embodiments] By providing such an elastic member in the ball moving portion inside the valve body, when the pump connected to the check valve stops, the force acting on the elastic member is released. Therefore, the elastic member expands and pushes the ball, increasing the falling speed of the ball and shortening the valve closing time when the pump is stopped, thereby preventing the occurrence of water hammer.

In carrying out the present invention, it is preferable that the elastic member is an elastic bellows filled with gas or an elastic bellows with a spring inserted therein. Furthermore, by making the bellows shaped like a truncated cone, where the surface that the ball contacts is smaller than the opposite surface, foreign matter entangled in the bellows can be easily removed, and there is no risk of foreign matter clogging, which is advantageous.

[Embodiments] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the same members as in FIG. 1 are given the same reference numerals.

A bellows 5 is provided in a ball moving portion inside the valve body 1c, and the bellows 5 is fixed to the valve body 1 by a bolt 4 that attaches a lid 3. The bellows 5 is made of an elastic material and has air sealed inside. Its shape is a truncated cone in which the surface that the ball 2 contacts is smaller than the opposite surface.

When the pump connected to this check valve operates, the liquid flows in the direction of the arrow from the inlet 1a to the outlet 1b of the valve body 1, and at this time, the flow of liquid causes the ball 2 to
floats up and moves as shown in FIG. 3, and the bellows 5 is compressed by the liquid pressure acting on the ball 2.

When the pump stops, the force acting on the bellows 5 is released, causing the bellows 5 to expand, and this force pushes the ball 2, increasing the falling speed of the ball 2, thereby shortening the valve closing time. to prevent water hammer from occurring. Furthermore, as in the embodiment, by making the surface of the bellows 5 in contact with the ball 2 smaller than the opposite surface, foreign matter entangled in the bellows 5 can be easily removed, thereby reducing the possibility of foreign matter clogging. It's good that it's gone.

In the above embodiment, air is sealed in the bellows, but a spring may also be inserted. Further, the material is not limited to a bellows, but any elastic member may be used as long as it is compressed when a ball floats due to liquid pressure comes into contact with it, expands and pushes the ball when the liquid pressure acting on the ball disappears.

[Effects of the invention] The invention has the following excellent effects.

(i) When pumping is stopped, the pressure in the piping decreases and the elastic member expands, which pushes the ball and increases the speed at which the ball falls, shortening the valve closing time. This can prevent water hammer from occurring due to backflow within the pipe. Moreover, this effect can be obtained without increasing the specific gravity of the ball.

(ii) Since the elastic member expands and contracts, the ball can move over a large distance, allowing a large opening for foreign matter to pass through, thereby preventing the valve from being clogged by foreign matter.

(iii) When using a coil spring as in the conventional example, fibers tend to get tangled in the coil part, and once tangled, it is difficult to remove, resulting in malfunction. When a cone-shaped bellows is used, short fibers are less likely to get tangled in the bellows, and even if long fibers become tangled, when the truncated cone-shaped bellows expands and contracts, the tangled fibers are pushed out in the direction of the smaller diameter of the bellows. Since it is removed after being removed, there will be no malfunction.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a conventional ball-type check valve, Figures 2 and 3 are cross-sectional views of a ball-type check valve according to an embodiment of the present invention, and Figure 2 shows a ball that closes the inlet. The same state as the third
The figure shows a state in which the ball floats and the inlet is opened. 1... Valve body, 1a... Inlet, 1b... Outlet, 1c... Inside the valve body, 2... Ball, 3...
Lid, 4... bolt, 5... bellows.

Claims (1)

[Claims for Utility Model Registration] (1) In a ball-type check valve equipped with a ball that floats up under liquid pressure to open a flow path and closes the flow path under its own weight, the ball moves inside the valve body when the liquid pressure A check valve characterized in that an elastic member is provided on a side surface of a fluid flow path, and is compressed when a ball floats in contact with the ball, and when liquid pressure acting on the ball is removed, expands and pushes the ball. (2) The check valve according to claim 1, wherein the elastic member is a bellows made of an elastic material filled with gas. (3) The check valve according to claim 1, wherein the elastic member is a bellows made of an elastic material into which a spring is inserted. (4) The elastic member is a bellows made of an elastic material filled with gas or a bellows made of an elastic material inserted with a spring, and the bellows has a frustum-like shape in which the surface in contact with the ball is smaller than the opposite surface. The check valve according to claim 1 of the utility model registration claim, characterized in that: