JPH1113932A - Water hammer preventing device for float valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of water hammering by slowly closing a valve element by providing a slow-closing device for applying a load on a connecting member for connecting a float and the valve element against the rising of the float and the movement of the valve element in its closing direction so as to suppress the sudden closing of the valve element and slowly closing the same. SOLUTION: When a discharge water pipe line 8 is sealed for some reason to cut off the discharging of water from a water tank 2, the water level of the water tank 2 is suddenly raised from a reference water level WL to a highest water level. But by a slow-closing device 10 provided between a flange 72A and a valve box cap 9 provided inside a valve rod 72 by interpolating a compression spring 10A, A force for countering the rising of a float 6 or the movement of a valve body 5 in its closing direction is applied to the valve rod 72 of a connecting member 7, and the sudden closing of the valve body 5 is prevented and the valve body is slowly closed. Especially, since near full closing of the valve body 5, the slow closing operation of the slow- closing device 10 is large and the valve body 5 is moved in its closing direction more slowly, by suppressing the sudden change of a flow inside a water supply pipe 1, the occurrence of water hammering is surely prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a float valve installed in a water tank, an industrial water tank, an agricultural water tank, or the like to control water hammer in a float valve applied to water, industrial, or agricultural water management. The present invention relates to a water hammer prevention device for a float valve.

[0002]

2. Description of the Related Art Conventionally, a float valve shown in FIG. 4 has been known which is installed in a water tank, an industrial water tank, an agricultural water tank, or the like, and is applied to water, industrial, or agricultural water management. ing. The float valve communicates with a water supply line 1 and is provided in a water tank 2, and a valve body 5 movably mounted inside the valve box 3 to open and close a valve box seat portion 4. A float 6 which rises to the surface of the water tank 2 and rises and falls with a change in water level, and a connecting member 7 which connects the float 6 and the valve element 5 to each other. As shown in FIG. The valve body 5 is brought into close contact with the valve box seat portion 4 via the connecting member 7 by the rise of the float 6 following the rise of the float to the maximum water level HWL.
To the water tank 2 and the water level in the water tank 2 is reduced to the reference water level WL by the discharge from the drain pipe 8 after the water supply is shut off.
The valve body 5 is separated from the valve box seat portion 4 via the connecting member 7 by the lowering of the float 6 following the lowering of the float 6 to lower the water supply amount (water input amount) from the water supply line 1 and the drainage line 8. The valve opening is maintained so that the amount of drainage (water output) from
The water level of the water tank 2 is configured to be maintained at the reference water level WL.

The connecting member 7 includes a pantograph 70, a float-side connecting cylinder 71 and a valve stem 72.
0 is pivotally supported at the lower end of the float-side connecting cylinder 71, the lower pivot point 70B of the pantograph 70 is pivotally supported at the upper end of the valve stem 72, and the center of the pantograph 70 is pivoted. The point 70C is pivotally supported by a stop bar 73 slidably inserted into the float-side connecting cylinder 71.
The center pivot point 70C is appropriately held so as not to move up and down. Therefore, as shown in FIG. 5, the float 6 that follows the rise of the water level in the water tank 2 to the maximum water level HWL.
As a result, the valve body 5 is pushed down, and the valve box seat portion 4
The valve is brought into a closed state in close contact with the water tank 2 as shown in FIG.
Of the float 6 following the drop of the water level to the reference water level WL causes the valve element 5 to be pulled up to be in a valve-open state separated from the valve box seat portion 4.

[0004] By the way, for some reason, the drainage pipe 8
Is blocked and the drainage (water discharge) from the water tank 2 is shut off,
The water level in the water tank 2 rises rapidly from the reference water level WL in FIG. 4 to the maximum water level HWL in FIG. When the valve element 5 is suddenly closed in this way, a sudden change occurs in the flow in the water supply pipe line 1, and a water hammer occurs. For this reason, conventionally, the water tank 2 is enlarged, and the rise in the water level of the water tank 2 when the drainage pipe 8 is closed is slowed, so that the valve body 5 is closed gently to avoid the occurrence of water hammer. I have. However, an increase in the size of the water tank 2 leads to an increase in cost, and there is a possibility that installation may be impossible due to restrictions on the installation space.

[0005]

That is, in the conventional countermeasure for preventing water hammer of the float valve, the size of the water tank must be increased, which leads to an increase in cost and a possibility of being unable to be installed due to restrictions on the installation space. There is also. Therefore, the present invention provides a water tank that is gently closed without increasing the size of the water tank, maintaining the current size, preventing the occurrence of water hammer, avoiding cost increases, and reducing installation space. It is an object of the present invention to provide a water hammer prevention device for a float valve capable of alleviating the above restrictions.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a valve box which is installed in a water tank in communication with a water supply pipe, and is movably mounted inside the valve box. A valve body that opens and closes a valve box seat, a float that floats on the water surface of the water tank and rises and falls with a change in water level, and a connecting member that connects the float and the valve body to each other; With the rise of the float following the rise to the maximum water level, the valve body is brought into close contact with the valve box seat portion via the connecting member to supply water from the water supply pipe to the water tank with the valve closed. The valve body is separated from the valve box seat portion via the connecting member by shutting down and lowering the float following the water level of the water tank being reduced due to the discharge after the water supply is cut off. From the water supply line to the water tank In the float valve configured to be watered, a force against the rising of the float and the movement of the valve body in the valve closing direction is applied to the connecting member to suppress the sudden closing of the valve body and slowly close the valve body. A closing device is provided.

According to the present invention, even if the water from the water tank is shut off for some reason and the water level in the water tank rises suddenly to the maximum water level, the floating member raises the valve and connects the valve to the connecting member by the gradual closing device. A force against the movement of the valve body in the valve closing direction is applied, and the rapid closing of the valve body can be suppressed and the valve can be closed gently.

[0008]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side view of a partially opened cross-sectional view of an embodiment of the present invention when a valve is opened. In this figure, a float valve communicates with a water supply line 1 and is installed in a water tank 2. 3, a valve body 5 movably inserted into the inside of the valve box 3 to open and close the valve box seat portion 4, a float 6 that floats on the water surface of the water tank 2 and moves up and down with a change in water level,
A connecting member 7 for connecting the float 6 and the valve body 5 to each other.
As shown in FIG. 2, the valve body 5 is brought into close contact with the valve box seat portion 4 via the connecting member 7 by the rise of the float 6 following the rise of the water level of the water tank 2 to the maximum water level HWL. With the valve closed, the water supply from the water supply line 1 to the water tank 2 is shut off, and the water level in the water tank 2 is reduced to the reference water level WL by the discharge from the drainage line 8 after the water supply is shut off. The lowering of the float 6 causes the connecting member 7
The valve body 5 is separated from the valve box seat portion 4 through the valve, and the valve opening degree at which the amount of water supplied from the water supply line 1 (water input amount) and the amount of water discharged from the drainage line 8 (water discharge amount) become equal. It is configured to hold the water level of the water tank 2 at the reference water level WL.

The connecting member 7 includes a pantograph 70, a float-side connecting cylinder 71 and a valve stem 72.
0 is pivotally supported at the lower end of the float-side connecting cylinder 71, the lower pivot point 70B of the pantograph 70 is pivotally supported at the upper end of the valve stem 72, and the center of the pantograph 70 is pivoted. The point 70C is pivotally supported by a stop bar 73 slidably inserted into the float-side connecting cylinder 71.
The center pivot point 70C is appropriately held so as not to move up and down. Therefore, as shown in FIG. 2, the float 6 that follows the rise of the water level of the water tank 2 to the maximum water level HWL.
As a result, the valve body 5 is pushed down, and the valve box seat portion 4
The valve is brought into close contact with the water tank 2 as shown in FIG.
Of the float 6 following the drop of the water level to the reference water level WL causes the valve element 5 to be pulled up to be in a valve-open state separated from the valve box seat portion 4. In addition, 9 in a figure shows a valve box cover.

On the other hand, a force against the lifting of the float 6 and the movement (down) of the valve element 5 in the valve closing direction is applied to the connecting member 7 to suppress the rapid closing of the valve element 5 and gradually close the valve element 5. Closing device 10
Is provided. The gradual closing device 10 includes a compression coil spring 10A interposed between a flange 72A provided at an intermediate portion of the valve stem 72 and the valve box cover 9.

In the above configuration, when the drainage pipe 8 is blocked for some reason and the drainage from the water tank 2 is shut off,
The water level of the water tank 2 rapidly rises from the reference water level WL in FIG. 1 to the highest water level HWL in FIG. However, a force against the lifting of the float 6 and the movement of the valve element 5 in the valve closing direction is applied to the valve rod 72 of the connecting member 7 by the gradual closing device 10, and the rapid closing of the valve element 5 is suppressed to gradually close the valve. Can be done. Especially,
In the vicinity of the fully closed valve body 5, the gentle closing of the slowly closing device 10 acts greatly, and the valve body 5 can be moved more gradually in the valve closing direction. Thus, the occurrence of water hammer can be reliably prevented. That is, without increasing the size of the water tank 2, the valve body 5 is gently closed while maintaining the current size.
Water hammer can be prevented from occurring. As a result, it is possible to avoid an increase in cost and to reduce restrictions on the installation space.

In the above embodiment, the pantograph type connecting member 7 is used. However, as shown in FIG. 3, a float valve using the operating arm type connecting member 7 may be used.
The same operation and effect as in the above-described embodiment can be obtained by providing the gradual closing device 10 including the compression coil spring 10A interposed between the flange 72A provided at the intermediate portion of the valve stem 72 and the valve box cover 9. Obtainable.

[0013]

As described above, according to the present invention, even if water from the water tank is shut off for some reason and the water level of the water tank rises suddenly to the maximum water level, the connection member can be connected to the connection member by the gentle closing device. A force against the rise of the float and the movement of the valve body in the valve closing direction is applied, and the valve body can be closed gently by suppressing the rapid closure of the valve body. Thus, the occurrence of water hammer can be reliably prevented. That is, it is possible to prevent the occurrence of water hammer by gently closing the valve body while maintaining the current size without increasing the size of the water tank. As a result, it is possible to avoid an increase in cost and to reduce restrictions on the installation space.

[Brief description of the drawings]

FIG. 1 is a side view when a valve is opened, showing a partial cross section of an embodiment of the present invention.

FIG. 2 is a side view of the embodiment of the present invention showing a partial cross section when the valve is closed.

FIG. 3 is a side view showing another embodiment of the present invention in a partial cross section when a valve is closed.

FIG. 4 is a side view of a conventional example with a partial cross section when a valve is opened.

FIG. 5 is a side view showing a conventional example with a partial cross section when a valve is closed.

[Description of Signs] 1 water supply line 2 water tank 3 valve box 4 valve box seat 5 valve body 6 float 7 connecting member 10 loose closing device

Claims (1)

[Claims] 1. A valve box connected to a water supply pipe and installed in a water tank, a valve body movably inserted into the valve box to open and close a valve box seat portion, and a water tank of the water tank. A float that rises and rises and falls with a water level fluctuation, and a connecting member that connects the float and the valve body to each other, and is provided by the rise of the float that follows the rise of the water level of the water tank to the highest water level, The valve body is brought into close contact with the valve box seat portion via the connection member to close the valve, thereby blocking water supply from the water supply conduit to the water tank, and lowering the water level of the water tank due to discharge after the water supply is cut off. When the float is moved down, the valve body is separated from the valve box seat portion via the connecting member to open the valve, and water is supplied from the water supply pipe to the water tank. In the float valve, the connection A float, which is provided with a slow-closing device that applies a force against the rise of the float and the movement of the valve body in the valve-closing direction to the member, and suppresses the rapid closing of the valve body to slowly close the valve body. Water hammer prevention device for valves.