JPS5813176Y2 - non-return valve - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a check valve equipped with a shock absorber for use in general fluid pipelines.

It has been conventionally known that when a backflow occurs in a fluid pipeline and the check valve is rapidly closed due to the backflow, a water leakage phenomenon occurs in the pipeline.

In order to prevent this, the valve body is composed of a main valve body 30 and an auxiliary valve body 31 as shown in FIG.
1 is gradually closed off by a dashpot 32 (see Japanese Utility Model Publication No. 12077/1983).

In this case, since the dashpot 32 protrudes outside the valve body 33, there is a disadvantage that the outer size becomes large, and there is also the inconvenience that side fluid is required for the operation of the dashpot 32.

Furthermore, in a general check valve, it is conventionally known to provide a dashpot 35 of a valve body 34 inside a valve body 36, as shown in FIG.

In this case, there is an advantage that the dashpot 35 does not protrude outside the valve box 36 and the fluid in the pipeline can be used as the working fluid for the dashpot 35.
is provided inside the valve box 36, it is not possible to adjust the flow rate of the dashpot 35 from outside the valve box 36, and it is necessary to adjust the dashpot 35 according to the installation conditions (flow rate, flow rate, piping situation, etc.). But I can't do this.

Also, since the dashpot 35 exists in the flow,
There are drawbacks that hinder distribution.

If the structure of the dashpot 35 shown in FIG. 6 is applied to the auxiliary valve body 31 shown in FIG. The disadvantage of not being able to adjust the flow rate of the dashpot from the flow rate remains unchanged.

Therefore, this invention aims to reduce the water hammer phenomenon in response to various changes in backflow pressure by making it possible to freely adjust the closing speed of the valve body near the fully closed state of the check valve from the outside. This is a technical issue.

The technical measures taken to solve the above technical problems are as follows.

That is, a buffer chamber is formed by an assembly of a main valve body having a peripheral wall and an auxiliary valve body fitted to the inner periphery of the peripheral wall, an elastic body is interposed between the two valve bodies, and the peripheral wall of the auxiliary valve body is is provided with an auxiliary valve port that is closed by the peripheral wall of the main valve body when the buffer chamber is compressed, a passage communicating with the buffer chamber and its front surface is provided in the peripheral wall of the auxiliary valve body, and a flow rate adjustment passage leading to the passage is connected to the valve body of the valve body. A flow rate regulating valve is provided between the inner circumferential portion of the seat and the outside of the valve port to adjust the flow rate of the flow rate regulating passage from outside the valve box.

The operation of the above technical means is as follows.

That is, the assembly of the main valve body and the auxiliary valve body is operated in the closing direction by the backflow pressure, and the auxiliary valve body abuts around the valve port, thereby closing most of the valve port.

In this state, the downstream side and the upstream side communicate with each other through the auxiliary valve port and are not completely shut off.

Subsequently, the fluid in the buffer chamber is discharged through the flow rate regulating passage due to the counter pressure acting on the main valve body, and the main valve body gradually closes the auxiliary valve port, and the flow rate in the flow rate regulating passage is controlled by the flow rate regulating valve outside the valve body. Since it can be adjusted by

The unique effects of this invention are as follows.

(1) When opening the valve port after it has been shut off, the valve port is opened when the main valve body and auxiliary valve body assembly separates from the valve port, regardless of the restoration of the buffer chamber. The opening is carried out quickly.

(2) Since it is an assembly of the main valve body and the auxiliary valve body, it can be removed as a unit for inspection and repair.

Next, the first embodiment of this invention is based on FIG. 1, the second embodiment is based on FIGS. 2 and 3, and the third embodiment is based on FIG.
This will be explained based on the diagram.

In FIG. 1 showing the first embodiment, 1 is a valve box connected to a pipe line, and fluid normally flows in from the upstream side A and flows out to the downstream side B.

A swing arm 3 is attached to the valve body 1 by a valve shaft 2, and a main valve body 5 is supported on the arm 3 by a pivot pin 4.

The main valve body 5 has a peripheral wall 6, and an auxiliary valve body 7 is fitted into the peripheral wall 6 in sliding contact with the peripheral wall 6, and a buffer chamber 8 is formed between the auxiliary valve body 7 and the main valve body 5.

One or more springs 9 are fitted in the buffer chamber 8 and always bias the main valve body 5 and the auxiliary valve body 7 in the direction of separating them.

A guide bolt 10 is freely inserted into the auxiliary valve body 7 while maintaining a watertight state.

The tip of this bolt 10 is screwed into and fixed to the main valve body 5.

The auxiliary valve body 7 also has a peripheral wall 11 .

This peripheral wall 11 is fitted in sliding contact with the inner surface of the peripheral wall 6 of the main valve body 5, and an auxiliary valve port 12 is provided in a portion of the peripheral wall 11 near the end surface in the radial direction of the auxiliary valve body T.

The part of the peripheral wall 11 where the auxiliary valve port 12 is provided does not fit into the peripheral wall 6 when the main valve body 5 is in the open state.
They are in a closed state and fit together when the main valve body 5 compresses the buffer chamber 8.

Therefore, as the buffer chamber 8 is compressed by the main valve body 5, the auxiliary valve port 12 is gradually closed by its peripheral wall 6.

The peripheral wall 6 of the main valve body 50 is pressed against the valve seat 19 when the main valve body 50 is closed, and the peripheral wall 11 of the auxiliary valve body 7 abuts against the valve body 1 at the inner peripheral portion of the valve seat 19 (the outer peripheral portion of the valve port 14).

Further, the peripheral wall 11 of the auxiliary valve body I is provided with the auxiliary valve D.
A passage 13 is provided at a position that does not intersect with passage 12.

One end of the passage 13 is open into the buffer chamber 8, and the other end is open to the end surface of the peripheral wall 11.

The valve box 1 has one end open around the valve port 14 at a position that matches the passage 13, and the other end of the valve box 1 outside the valve port 14.
A partially open flow rate regulating passage 15 is provided.

This flow rate adjustment passage 15 is drawn out to the outside in the middle thereof, and a control valve 16 is provided at that part.

In addition, a through hole 11 communicating with the buffer chamber 8 is provided in the center portion of the auxiliary valve body 7, and the through hole 11 is always connected to the buffer chamber 8.
A check valve body 18 is provided with elasticity so as to close the T.

Note that 20 indicates a valve chamber.

The check valve of the first embodiment described above opens as shown by the chain line in the figure when fluid is flowing through the pipe, allowing free passage of fluid.

In this case, the volume of the buffer chamber 8 is maximum, and the same fluid as the flow is filled with the same pressure as the inside of the valve chamber 20, and the auxiliary valve port 1
2 is located outward from the peripheral wall 6 of the main valve body 5.

Now, if the fluid in the pipeline flows backwards for some reason, the main valve body 5 begins to block, as shown by the solid line in the figure, and the auxiliary valve body 7 first
The end surface of the peripheral wall 11 contacts the portion of the valve box 1 around the valve port 14, and the passage 13 and the flow rate adjustment passage 15 communicate with each other.

Thereafter, the main valve body 5 gradually compresses the buffer chamber 8 by overcoming the pressure of the spring 9 and the fluid in the buffer chamber 8 due to the action of the backflow fluid, and at the same time, the fluid in the buffer chamber 8 is discharged from the flow control valve 16. It gradually flows out depending on the degree of adjustment.

As the main valve body 5 compresses the buffer chamber 8, the auxiliary valve port 1
2 is also gradually closed, and the main valve body 50 peripheral wall 6 end face becomes the valve seat 19.
By contacting the auxiliary valve port 12, the auxiliary valve port 12 is completely closed, and the upstream side A and the downstream side B are completely cut off.

Next, when the fluid flow returns to normal, the main valve body 5 and the auxiliary valve body 7 supported by it return to the position indicated by the chain line in the figure, and the valve port 14
to open.

In this case, when the end surface of the peripheral wall 6 of the main valve body 5 begins to separate from the valve seat 19, the volume of the buffer chamber 8 gradually expands due to the pressing force of the spring 9, and the pressure inside the chamber decreases, so that the fluid flows through the check valve body. 1
8 is opened and fluid flows into the buffer chamber 8 through the through hole 17, and when the end surface of the peripheral wall 11 of the auxiliary valve body 7 begins to separate from the portion of the valve box 1 around the valve port 14, fluid also flows into the buffer chamber 8 from the passage 13.

The fluid will flow in until the pressure within the valve chamber 20 is the same as the pressure within the valve chamber 20.

Next, a second embodiment shown in FIGS. 2 and 3 will be described.

This embodiment has the same structure as the previous embodiment except for a slight difference in the structure of the auxiliary valve body 7a, so the same parts will be given the same reference numerals and their explanation will be omitted. do.

The auxiliary valve body 7a in this embodiment has several through holes 21 in the peripheral wall 11 of the auxiliary valve body 7a instead of the through holes 17 and check valve body 18 of the previous embodiment.

As shown in FIG. 3, this through hole 21 is provided at a position that does not intersect with the auxiliary valve port 12, and one end thereof is connected to the buffer chamber 8.
The other end is open to the end surface of the peripheral wall 11.

Therefore, as shown in FIG. 2, when the auxiliary valve body 7a abuts around the valve port 14, each through hole 21 is closed, and the buffer chamber 8 is connected to the pipeline through only the passage 13 and the flow rate adjustment passage 15. As a result, the same buffering effect as in the previous case is performed.

In the third embodiment shown in FIG. 4, a lift type check valve is provided with a shock absorbing device similar to the above-mentioned embodiments.

Since there is no substantial difference from the above-mentioned embodiment, especially the first embodiment shown in FIG. 1, except that the support structure for the main valve body 5a is of a lift type, the same parts will be given the same reference numerals and explained. omitted.

In addition, although illustration is omitted, as other examples,
Among check valves having a plurality of valve ports, there is a type in which one of the valve ports is fitted with a valve body having the above-mentioned shock absorbing device, and the other valve ports are fitted with valve bodies without this.

[Brief explanation of drawings]

Fig. 1 is a sectional view of the first embodiment, Fig. 2 is a sectional view of the second embodiment, Fig. 3 is a front view of the buffer plate, Fig. 4 is a sectional view of the third embodiment, and Fig. 5. , FIG. 6 is a sectional view of a conventional example. 5... Main valve body, 6... Peripheral wall, 7.7a
...Auxiliary valve body, 8...Buffer chamber, 9...
...Spring, 10...Bolt, 11...
... Peripheral wall, 12 ... Auxiliary valve port, 13 ...
- Passage, 14... Valve port, 15... Flow rate adjustment passage, 16... Control valve.

Claims (1)

[Scope of utility model registration request] The main valve body is provided with a peripheral wall that protrudes so as to come into pressure contact with the valve seat when closed, and has a peripheral wall that slides and fits into the inner periphery of the peripheral wall and that protrudes so as to come into contact with the inner periphery of the valve seat when closed. An auxiliary valve body is provided, a buffer chamber is formed by both valve bodies, an elastic body is interposed between the main valve body and the auxiliary valve body, and the peripheral wall of the main valve body is formed on the peripheral wall of the auxiliary valve body when the buffer chamber is compressed. A buffer chamber and a passage leading to the front surface of the buffer chamber are provided on the peripheral wall of the auxiliary valve body, and a flow rate adjustment passage leading to the passage is connected between the inner periphery of the valve seat of the valve body and the outside of the valve opening. A check valve comprising a flow rate control valve provided between the flow rate control passage and adjusting the flow rate of the flow rate control passage from outside the valve box.