JP2008029682A - Drain valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve body of a drain valve equipped with a restriction means that restricts a flow volume of a fluid flowing from a primary side to a secondary side when closing a communication port, and to prevent the occurrence of water hammer or chattering phenomenon by preventing a sudden closure of the drain valve and by preventing the valve body from being pressed suddenly against a valve seat at the closing moment. <P>SOLUTION: The drain valve 100 has the communication port 2 communicating with the primary side A and the secondary side B and the valve body 4 for opening or closing the communication port 2. The valve body 4 is equipped with the restriction means for restricting flow volume of fire extinguishing water flowing from the primary side A to the secondary side B when closing the communication port 2. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a drain valve, and more particularly to a drain valve in an automatic valve such as a tunnel fire extinguishing facility.

  The automatic valve of the water spray fire extinguishing equipment used when a tunnel fire occurs has a drain valve. The drain valve is normally open due to the elasticity of the spring mounted inside, and discharges residual water in the secondary valve of the automatic valve of the tunnel fire extinguishing equipment, but a fire occurs. Sometimes, the automatic valve is opened and the pressure of the fire-fighting water supplied exceeds the elasticity of the spring, the valve body is pushed down, and the drain valve closes.

FIG. 5 is an example of an apparatus around an automatic valve in a tunnel fire extinguishing equipment system. As shown in the figure, when the automatic valve 80 is closed, the water spray head 85 is not filled with water from the secondary side of the valve, and a drain valve (automatic drain valve) 100) is also connected. 6 and 7 show the structure and operation of a flat valve body drain valve 200 that is conventionally used as the drain valve 100 around the automatic valve 80. The valve body 51 is pulled up by the normal spring 52, and the communication port 54 of the drain valve 200 is opened to communicate with the secondary side B (FIG. 6). When this occurs, the valve body 51 is pushed down, seated on the valve seat 53, and the drain valve 200 is closed (FIG. 7). In addition to such a flat valve body type, a ball-type drain valve is often used (for example, Patent Document 1).
Japanese Patent Laid-Open No. 2003-236010

  By the way, when the conventional drain valve is closed, the high-pressure fire-fighting water on the primary side of the communication port flows rapidly into the secondary side that is open to the atmosphere, but the secondary side outlet is normally throttled, so vibration and Generation of noise and so-called water hammer phenomenon occurs. In addition, since the drain valve is a flat type, the valve body is suddenly pressed against the valve seat when the drain valve is to be closed instantly, and the valve body may float from the valve seat due to the reaction. is there. If this is repeated, a so-called chattering phenomenon occurs, and the drain valve cannot be closed well even if the primary side exceeds a predetermined pressure.

  The present invention has been made to solve the above-described problems. In a fire extinguishing facility that extinguishes a fire by sprinkling water by opening an automatic valve, the automatic valve is connected to a drain valve, and the drain valve is connected to a primary side and a secondary side. A restricting means for restricting the flow rate of fluid flowing from the primary side to the secondary side when the communication port is closed, comprising a communication port for communicating with the secondary side and a valve body for opening and closing the communication port; It is characterized by taking the disc.

  Further, the valve body of the drainage valve has a circular trapezoidal portion, and a first valve body that opens and closes the communication port when the circular trapezoidal portion comes into contact with and separates from the valve seat; A second valve body that is formed in the shape of a truncated cone that is coaxially in contact with the first valve body, and a truncated cone that has the same bottom surface as the second valve body and coaxially contacts the second valve body. And a third valve body formed in a shape.

  The second valve body has a diameter of 7/10 or more of the inner diameter of the communication port, a height of 6/10 of the sliding distance of the valve body, and the third valve body has its The taper angle of the truncated cone is between 60 degrees and 90 degrees.

  The valve body of the drainage valve has a limiting means to limit the flow rate of the fluid flowing from the primary side to the secondary side when closing the communication port, so the drainage valve does not close suddenly and immediately closes The body is not suddenly pressed against the valve seat, and no water hammer or chattering occurs.

  An embodiment for carrying out the present invention is shown in FIGS. 1 and 2, and the configuration and operation procedure of the drain valve will be briefly described below. FIG. 5 also shows the installation of the drain valve in the automatic valve of the tunnel fire extinguishing equipment system.

Embodiment 1
FIG. 1 shows the structure of a drain valve 100 according to the present invention.

  This drain valve 100 is connected to the secondary side of the automatic valve 80 as in the prior art, and communicates with the casing 1 forming the outer frame of the valve, the primary side A, and the secondary side B. Connecting valve 2, valve seat 3 positioned and provided at the end of communication port 2, and valve body 4 that slides in the axial direction of the valve and opens and closes the valve seat 3. And a spring 5 that pushes up the valve body 4 and a knob 6 that adjusts expansion and contraction of the spring 5 to set a predetermined opening degree of the drain valve 100.

  The valve body 4 has a circular trapezoidal portion. The first valve body 41 that opens and closes the communication port 2 when the circular trapezoidal portion separates from and contacts the valve seat 3, and the first valve body 41 is contracted. A second valve body 42 that is formed in a circular shape in contact with the first valve body 41 and coaxially with the first valve body 41; and a bottom surface that has the same diameter as the second valve body 42; A third valve body 43 formed in the shape of a truncated cone in contact with the second valve body 42 coaxially.

  The portion formed by the second valve body 42 and the third valve body 43 (shaded portion in the figure) is a primary side before the first valve body 41 is closed as a restricting means for restricting the flow rate. The flow rate of fire-extinguishing water flowing from A to the secondary side B can be narrowed down. Therefore, the flow rate flowing by the piece when closing is limited, the valve body 4 can be prevented from closing suddenly, and water hammer can be prevented. Further, when the first valve body 41 is closed, the pressure fluctuation on the primary side A and the secondary side B can be moderated by the piece, so that the valve body 4 is closed without being lifted off from the valve seat 3 by the reaction. Thus, chattering can be prevented.

  Further, the second valve body 42 having a trapezoidal shape preferably has a diameter of 7/10 or more of the inner diameter of the communication port 2, and the height is 6/10 of the sliding distance of the valve body 4. (Details will be described in the following examples).

  In addition, it is desirable that the truncated cone-shaped third valve body 43 has a tapered angle between 60 degrees and 90 degrees (details will be described in the following embodiments).

  When such a drain valve 100 is connected to the secondary side of the automatic valve 80, the valve body of the drain valve 100 is always discharged to the empty secondary side by the fire-extinguishing water that flows rapidly when the automatic valve 80 opens. Even if 4 is pushed down vigorously, the communication port 2 is restricted by the second valve body 42 and the third valve body 43, so that the valve body 4 is surely seated, and the fire-extinguishing water flowing from the automatic valve 80 is discharged. It is supplied to the water spray head without waste and discharged at a predetermined pressure.

Example 1
The table of FIG. 3 and FIG. 4 disclose the experimental results of the present invention.

  According to this, the disc-shaped second valve element 42 moves in the axial direction of the first valve element 41 and is loosely inserted into the communication port 2, but its diameter is 7/10 or more of the inner diameter of the communication port 2. If so, the effect of water hammer and chattering prevention is good. On the other hand, if the height of the second valve body 42 having a trapezoidal shape is set to 6/10 of the movement distance with reference to the distance of the first valve body 41 moving in the axial direction, water hammer and chattering The effect of prevention is good. Further, if the third valve body 43 having a truncated cone shape has no taper angle or 90 degrees or more, the third valve body 43 has a circular shape, and the effects of preventing water hammer and chattering do not appear so much. Conversely, if the taper angle is 60 degrees or less, the entire length of the third valve body 43 is too long, and the structure of the drain valve becomes large. Therefore, the taper angle of the third valve body 43 may be set between 60 and 90 degrees.

  Next, a procedure for operating the drain valve 100 will be briefly described with reference to FIGS.

  First, as shown in FIG. 1, the valve body 4 is separated from the valve seat 3, and the drain valve 100 is open.

  Next, as shown in FIG. 2, when water for fire extinguishing (not shown) flows in from the primary side A and the water pressure exceeds a predetermined value against the elasticity of the spring 5, the valve body 4 is pushed down, and the first valve body The circular trapezoidal portion 41 is seated on the valve seat 3 so that the drain valve 100 is closed. In this case, the piece formed by the second valve body 42 and the third valve body 43 (the hatched portion in the figure) extinguishes from the primary side A to the secondary side B just before the first valve body 41 is closed. Since the flow rate of irrigation water can be narrowed down, the flow rate of fire-fighting water is limited when closing, and the valve body 4 cannot be closed rapidly, and water hammer can be prevented. Further, when the first valve body 41 is closed, the pressure fluctuation on the primary side A and the secondary side B can be moderated by the piece, so that the valve body 4 can be closed smoothly without being lifted to the valve seat 3 by reaction. The chattering phenomenon can be eliminated.

  According to this embodiment, in the fire extinguishing equipment that extinguishes fire by sprinkling water from the water spray head 85 by opening the automatic valve 80, the automatic valve 80 is connected to the drain valve 100, and the drain valve 100 is connected to the primary side A. A communication port 2 that communicates with the secondary side B, and a valve body 4 that opens and closes the communication port 2, and when the communication port 2 is closed, the fire extinguishing that flows from the primary side A to the secondary side B Limiting means for limiting the flow rate of water is provided in the valve body 4. Specifically, the valve body 4 of the drain valve 100 includes a first valve body 41 that opens and closes the communication port 2 by having a circular trapezoidal portion, and the circular trapezoidal portion is connected to and separated from the valve seat. A second valve body 42 having a diameter reduced from that of the first valve body 41 and formed coaxially with the first valve body 41, and a bottom surface having the same diameter as the second valve body 42, Since it has a flow restricting means composed of a third valve body 43 formed in the shape of a truncated cone that abuts coaxially with the two-valve body 42, water hammer and chattering phenomena are caused when the valve body 4 is closed. Therefore, the drain valve 100 can function normally, and there is no problem with the equipment.

  In the above-described embodiment, the third valve body 43 is described as a truncated cone shape. However, the third valve body 43 is not limited to a truncated cone shape, and may be a truncated cone shape.

The drain valve 100 according to the first embodiment is open A state in which the drain valve 100 according to the first embodiment is closed. Experimental results of Example 1 A piece formed by the second valve body 42 and the third valve body 43 (a restricting means for restricting the flow rate). Part of the equipment around automatic valves in tunnel fire extinguishing equipment systems Conventional drain valve 200 is open The state where the conventional drain valve 200 is closed

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Casing 2 Communication port 3 Valve seat 4 Valve body 5 Spring 6 Knob A Primary side B Secondary side 80 Automatic valve 85 Water spray head 100 Drain valve 200 Drain valve

Claims (3)

In fire extinguishing equipment that extinguishes fire by watering with automatic valve opening,
The automatic valve is connected to a drain valve, and the drain valve includes a communication port that communicates the primary side and the secondary side, and a valve body that opens and closes the communication port, and when the communication port is closed, A drainage valve characterized in that limiting means for limiting the flow rate of fluid flowing from the primary side to the secondary side is provided in the valve body.   The valve body of the drainage valve has a circular trapezoidal portion. The first valve body that opens and closes the communication port when the circular trapezoidal portion separates from and contacts the valve seat, and the diameter of the first valve body is reduced. The second valve body is formed in the shape of a truncated cone that abuts on the same axis as the first valve body, and has the shape of a truncated cone that abuts the bottom surface on the same axis as the second valve body. The drain valve according to claim 1, further comprising a third valve body that is formed. The diameter of the second valve body is 7/10 or more of the inner diameter of the communication port, the height is 6/10 of the sliding distance of the valve body,
The drain valve according to claim 1 or 2, wherein the third valve body has a truncated cone-shaped taper angle between 60 degrees and 90 degrees.