JP2563921Y2 - Pilot valve for water control device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pilot valve for a water control device in which a valve body of a water control device is opened and closed by using water pressure, and the water pressure is applied in one of opening and closing directions. is there.

[0002]

2. Description of the Related Art Conventionally, in order to open and close a gate or a valve, which is a water control device, there is a type in which the operation of a door or a valve is controlled by a pilot valve. As shown in FIG.
When the valve 1 is installed,
A detecting device (operating portion) 2 for detecting a water level and a pilot valve 3 linked by the detecting device 2 are provided in parallel. The pilot valve 3 is connected with a water supply pipe 4 leading from an upstream water passage and two water flow pipes 6 connected to the valve body 5 of the valve 1 so that water pressures are applied in opposite directions. A rod 8 is connected to the float 7 of the detection device 2 and is connected to a piston 10 of the pilot valve 3 via a rotating cross arm 9 so as to interlock.

When the float 7 moves due to the water level, the pilot valve 3 connects the water supply pipe 4 to one of the two water pipes 6, and operates the valve element 5 of the valve 1 by the upstream water pressure to open the valve 1. It opens and closes.

[0004] As shown in FIG.
No. 8472), in the case where the water distribution pipe 11 is provided with the needle valve 12, an opening / closing device 13 is provided in series, and a pilot valve 3 for controlling the opening / closing device 13 is provided. Switchgear 13 is a cylinder
The pilot valve 3 applies an upstream water pressure to one side of the piston 15.

[0005]

In the water control device described above, the rotating cross arm 9 for interlocking the piston 10 of the pilot valve 3 is equipped with an unbalance weight 16 and a counter weight 16a. Although not shown in the drawings, since the stopping weight is provided by engaging with the shaft of the rotating cross arm 9, there is a problem that the device in this portion becomes large.

Further, since the structure of the needle valve 12 is excessively simplified, the needle valve 12 is immediately changed according to a change in water level, water pressure or flow rate due to opening and closing of the needle valve 12.
Since the opening / closing operation of 12 is stopped, the opening / closing operation becomes insufficient, so that the water level, the water pressure, or the flow rate does not return to the average value, so that there is a problem that the opening / closing operation is frequently repeated.

An object of the present invention is to provide a pilot valve that can operate a water control device stably and requires a small installation space.

[0008]

According to the present invention, there is provided an operating part which communicates with a flowing water channel and is linked to a water level, a water pressure and a water pressure difference.
An axially slidable control rod of the operating portion is inserted into a cylindrical piston rod fixed to a pair of pistons and slidably provided in a cylindrical casing, and stoppers are provided at both ends of the piston rod. Are fixed to the control rod at an interval, and two casing walls are provided between the pair of pistons.
Two water pipes and a water supply pipe between the two water pipes, the two water pipes communicating with a separation chamber formed through a piston provided with a valve body of a cylinder provided in the water control device; It is characterized by communicating with the upstream waterway.

[0009]

First, by connecting the operating portion to the downstream flowing water channel, the control rod is operated by the water level, the water pressure and the water pressure difference, and the control rod slides in the axial direction. When two water pipes are located between a pair of pistons, the water pressure on the upstream side is applied to the pistons connected to the valve body in opposite directions by the water supply pipe, so that the water control device remains stationary. It is. Here, even if the water level or the like of the downstream flowing water channel fluctuates, since the piston rod is supported by the frictional force via the piston on the casing wall, if the stopper of the control rod does not press against the piston rod, The water control device can maintain the current state.

When the stopper presses the piston rod to one side, one of the water pipes communicates with the outside air,
The water control device operates in the opening direction or the closing direction. Also, when the stopper pushes the piston rod to the other,
The other water pipe communicates with the outside air, and the water control device operates in the closing direction or the opening direction.

[0011] When the operating portion is linked to the water level,
When the water level rises to near the allowable upper limit water level, the piston rod is pressed, and the water control device operates in the closing direction. As a result, the downstream water level will soon begin to drop, but the piston rod will have play with the control rod, and even if the control rod moves, the piston will remain stopped in the casing due to the frictional resistance of the piston. The closing movement continues.

When the water level further decreases, the play of the piston rod stops, and the piston rod moves down as the water level decreases to move the position of the piston. Then, when the two water pipes communicate with the water supply pipe, the water pressure is evenly applied to the chamber of the cylinder, the movement of the piston is stopped, and the water control device is in a stationary state.

Although the water control device flows down even when the water control device comes to a standstill, the inflow from the upstream decreases more than the outflow to the downstream. It will stop at the position, and eventually the water level will be stable. Further, as described above, the water level at the time of stopping the closing operation of the water control device is determined by determining the interval of the play of the piston rod, so that the water level is settled near the planned water level.

The change in the water level after the water control device is stopped cannot be accurately predicted because the play amount of the piston rod is absorbed. However, even if there is some difference in prediction, the water level will be closer to the planned water level if the opening and closing speed of the water control device is adjusted.

When the water level drops to near the allowable lower limit water level, the piston rod is pushed by the stopper so that the water supply pipe communicates with only one of the water pipes, and water pressure is applied to one side of the piston of the water control device. The device starts to open and raises the downstream water level.

The subsequent operation operates in the same manner as described above. Even if the control rod moves, the piston rod stops until there is no play in the piston rod, and the piston rod is moved after contacting the stopper. And if it operates slowly and makes one side water pipe communicate with a water supply pipe again, a water control apparatus will be in a stop state.

After that, the water level continues to rise, but since the water level is vertically symmetrical with respect to the planned water level, the water level almost reaches the planned water level as in the case of the closing operation.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, of the control of the water level, the water pressure and the flow rate, the water level is taken as an example, and the operating part is used for detecting the water level. FIG.
As shown in FIG. 5, a water pipe 17 having one end opened in the reservoir on the upstream side has the other end opened downward in the energy reduction pond 18. A sleeve (valve element) 19 of the valve (water control device) 1 is slidably mounted on the outer peripheral surface of the opening, and is made liquid-tight by a seal 20. On the bottom of the energy-reducing pond 18 below the sleeve 19, the top of the spheroid is cut off and hollowed out,
A cone 21 having a slit 21a uniformly formed around the periphery thereof is fixed.

The cylinder 22 of the valve 1 is provided at the tip of the water pipe 17.
And a hollow piston 23 having a volume equal to the weight of water equal to the total weight of the valve 1 in the cylinder 22.
And divides the inside of the cylinder 22 into two compartments.
The piston 23 and the sleeve 19 are connected by a rod 24.

The water supply pipe 4 branched from the water supply pipe 17 is provided with an opening / closing speed control valve 25 in the middle thereof so that the pilot valve 3 in a vertical posture is provided.
Is connected to the center of the cylindrical casing 26. Also,
The two water pipes 6 connected to the upper end and the lower end of the cylinder 22 are connected to a joining chamber 27 provided on the outer periphery of the casing 26 away from the center of the casing 26 to the target. A slit 28 is cut in the wall of the casing 26 in each joining chamber 27. In addition, the deceleration pond 18
A water channel 30 having a control gate 29 is formed on the downstream side of.

As shown in FIG. 2, the pilot valve 3 is provided with a float chamber 31 and a float 32 is housed with a gap between the float chamber 31 and the chamber wall as small as possible. The inside of the float chamber 31 is communicated with the water in the damping pond 18 via the water inlet 33 that is reduced as much as possible within a range where the water level can follow the water level fluctuation in the damping pond 18. The buoyancy applied to the plane area of the float 32 is sufficiently larger than the operating resistance of the pilot valve 3. Then, a planned water level 34 is set in the energy-reducing pond 18, and an allowable upper limit water level 35 and an allowable lower limit water level 36 are set symmetrically in the vertical direction, and the position of the float 32 is balanced with the planned water level 34.

In the casing 26 of the pilot valve 3,
Two pistons with a gap larger than the interval between two slits 28
A cylindrical piston rod 38 to which the 37 is fixed is slidably provided. A control rod 39 is provided to penetrate the piston rod 38. Above and below the piston rod 38, a stopper 40 is fixed to the control rod 39, and a gap a is formed so that the piston rod 38 can be pivoted in the axial direction.
Is provided. The lower end of the control rod 39 is attached to the float 32.
Is screwed on to make the length adjustable. Therefore, the amount of movement of the float 32 can be increased or decreased by changing the length of the control rod 39, and the allowable upper limit water level 35 can be determined. Note that the allowable upper limit water level 35 can be determined by moving the casing position, and the casing 26 is provided in the air but may be in water.

The slidable gap a of the piston rod 38 is
The slit 28 is smaller than half the difference between the allowable upper limit water level 35 and the allowable lower limit water level 36, and is smaller than the allowable upper limit water level 35, the closing operation stop water level 41, and the opening operation stop water level 42 and the allowable lower limit water level 36.
Is equal to the width minus the width.

The outer space between the upper and lower pistons 37 is set to a value obtained by subtracting the gap between the piston rod 38 from the water level difference between the allowable upper limit water level 35 and the allowable lower limit water level 36, as compared with the inner space between the slits 28. Also, the width and outer diameter of the joining chamber 27 are made sufficiently large, and the width of the slit 28 is made as small as possible by making the diameter of the casing 26 of the pilot valve 3 sufficiently large.

The amount of change in the water level after the stop of the opening / closing operation of the valve 1 is assumed based on the required opening / closing speed of the valve 1.
It is set above and below 34. The magnitude of the water level change after the opening / closing operation is stopped is, of course, proportional to the required opening / closing speed of the valve 1. Therefore, in the downstream area, the water level and water pressure fluctuate greatly with the change in water usage, and it is necessary to increase the opening / closing speed.
The opening operation stop water level 42 has a large interval from the planned water level 34.

Next, the operation will be described. If the water level in the damping pond 18 is almost the planned water level 34, the pilot valve 3
One piston 37 is outside the two slits. Energy reduction pond
When the water level in 18 rises, first, the control rod 39 rises inside the stopped piston rod 38 due to the rise of the float 32, and the lower stopper 40 contacts the lower end of the piston rod 38. When the water level rises further, the piston rod
38 rises and the two pistons 37 move upward.

When the water level in the damping pond 18 rises to a water level lower than the allowable upper limit water level 35 by the width of the slit 28, the lower surface of the lower piston 37 comes to the lower end of the lower slit 28,
A part of the lower slit 28 starts to be exposed, and the compartment below the piston 23 of the cylinder 22 of the valve 1 communicates with the outside air. For this reason, the water pressure on the lower surface of the piston 23 decreases, the piston 23 and the sleeve 19 descend, the flow path between the sleeve 19 and the cone 21 contracts, and the closing operation starts.

By the way, at this stage, the valve 1
Since the closing operation speed is extremely low, the water level of the deceleration pond 18 normally keeps rising, and when the water level reaches the allowable upper limit water level 35, the entire lower slit 28 is exposed, and the valve 1 keeps closing at a constant speed. .

The behavior of the water level of the deceleration pond 18 after that,
There are two cases: a case where the water intake is stopped by completely closing the water intake 29, and a case where the water intake is reduced by partially closing the water control gate 29.

First, when stopping the water intake by completely closing the water control gate 29, the water level continues to rise until the valve 1 is fully closed. Therefore, since the closing operation speed of the valve 1 becomes extremely high, there is a possibility that a water hammer in the water pipe 17 is generated and rupture occurs. However, since the cone 21 composed of a part of the spheroid is used, at the beginning of the closing operation, the flow path is sharply reduced, but at the end, the sleeve 19 and the outside of the cone 21 become parallel. So
It is not easy to completely close. Therefore, the water hammer is reduced. In addition, since the inside of the cone 21 is hollowed and the slit 21a is cut evenly on the outer periphery, the cone 21
No vortex is generated on the outer periphery of the sleeve 19, so that the sleeve 19 does not vibrate.

When the intake gate 29 is partially closed to reduce the amount of water intake, the water level in the detonation pond 18 starts to decrease as the closing operation of the valve 1 progresses. At this time, when the float 32 moves down, the stopper 40 separates from the lower end of the piston rod 38, and the piston rod 38 loses support. Therefore, only the control rod 39 descends while the piston rod 38 remains stopped. Therefore, at this stage, the valve 1 keeps opening at a constant speed.

However, when the closing operation stop water level 41 is higher than the slit 28
When the water drops to a water level higher by the width of the valve 1, the valve 1 continues to be opened, but the opening speed gradually decreases, and when the closing operation stop water level 41 is reached, the lower surface of the lower piston 23 is slit.
When the valve 1 is lowered to the lower end of the valve 28, the lower slit 28 is completely closed and the valve 1 is stopped.

The reason why the water level of the energy attenuating pond 18 has dropped from the allowable upper limit water level 35 to the water level 41 at which the closing operation is stopped is that the outflow amount is larger than the inflow amount of the energy attenuating pond 18. Therefore, even after the valve 1 stops, the water level continues to decrease. However, if the water level of the energy-reducing pond 18 decreases, the amount of runoff decreases, so that the water level does not decrease unnecessarily and is stabilized at a certain level. Therefore, the play of the piston rod 38,
That is, if the setting of the closing operation stop water level 41 is appropriate, the water level finally reaches a water level close to the planned water level 34.

However, the amount of change in the water level after the stop of the opening / closing operation cannot be accurately predicted. However, if the opening degree of the opening / closing speed control valve 25 is adjusted to make the closing operation speed of the valve 1 appropriate, the water level becomes higher. It will be very close to the planned water level of 34.

Next, when the water level shifts from the state of the permissible upper limit water level 35 to the planned water level 34, the valve 1 stops, but as the water level goes down, the piston 37 also goes down.
When the water level becomes higher than the allowable lower limit water level 36 by the width of the slit 28, the upper side of the upper piston 37 coincides with the upper side of the upper slit 28. Therefore, when the valve 1 starts to operate and reaches the allowable lower limit water level 36, the upper piston 37
Of the upper slit 28 coincides with the lower side of the upper slit 28. As a result, the water level starts rising soon, but the valve 1 keeps opening at a constant speed while the water level rises to a water level lower than the opening stop water level 42 by the width of the slit 28.

However, after that, when the speed becomes slow and the water level reaches the opening operation stop water level 42, the opening operation of the piston 37 is completely stopped and the valve 1 is in a stationary state, but the water level continues to rise due to inertia. Also in this case, the water level is settled near the planned water level 34. After the valve 1 operates in this manner, the water level always falls near the planned water level 34, so that the piston 37 can be prevented from frequently operating.

Next, the operation of the float chamber 31 will be described. The resistance of the pilot valve 3 is relatively large because it is a static frictional resistance when it starts moving, but it decreases drastically once it starts to move because the resistance changes to dynamic frictional resistance. Therefore, in general, the piston 37 moves too much. As a result, since the pilot valve 3 moves intermittently, the movement of the valve 1 may not be smooth. However, the gap between the float 32 and the float chamber 31 and the size of the water inlet 33 are reduced as much as possible. Therefore, when the float 32 moves slightly, the water level in the float chamber 31 fluctuates in the direction opposite to the movement of the float 32, and the operating force of the float 32 disappears. Therefore, the float 32 moves very little by little, so that the valve 1
Movement is also smooth.

In the above description, the case where the number of the floats 32 is one has been described. However, if the floats are divided into two in accordance with Japanese Patent Application No. 2-113818, it can be used for firm pond. Also, in accordance with Japanese Patent Application No. 3-278472, a spring is used in combination with a needle valve and a diaphragm in place of the valve 1 and the float 32, and a water pressure downstream of the needle valve is introduced into the diaphragm to provide a pressure reducing valve.
If upstream water pressure is introduced, it becomes a safety valve. Further, if the number of diaphragms is made two and the pressure difference is detected by introducing the water pressure of the enlarged portion and the constricted portion of the Venturi tube, a constant flow valve can be obtained.

The required opening / closing speed of the valve 1 differs depending on the application. For example, in the case of a constant flow valve, there is no need to follow a change in the amount of water used downstream. Therefore,
The opening / closing speed is sufficient if it follows the upstream condition, that is, changes in water pressure, so that the opening / closing speed can be quite low. In such a case, the accuracy is better when the interval of the flow rate in place of the interval between the opening / closing operation stop water level and the planned water level is small.

[0040]

[Effects of the Invention] Since the present invention is constructed as described above, the piston can play in the axial direction by the piston rod and the control rod, and the water control device can be stopped even if the operating portion slightly changes. When the water control device is activated, the operation is easily stopped by play, and the frequency of opening and closing of the water control device can be reduced. In addition, since the operating section is directly connected to the pilot valve, the installation space is small, and it can be used for a conventional water control device.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a water control device according to an embodiment of the present invention.

FIG. 2 is a side sectional view of the pilot valve for explaining an operation state of the pilot valve according to the embodiment.

FIG. 3 is a side sectional view of a conventional cone sleeve valve.

FIG. 4 is a side sectional view of a conventional needle valve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water control device 4 Water supply pipe 6 Water flow pipe 18 Flowing water channel 19 Valve element 22 Cylinder 23 Piston 26 Casing 31 Operating part 37 Piston 38 Piston rod 39 Control rod 40 Stopper

Claims (1)

(57) [Scope of request for utility model registration] An operating part which communicates with a flowing water channel and is interlocked with a water level, a water pressure and a water pressure difference is provided. A control rod slidable in an axial direction of the operating part is fixed to a pair of pistons and a cylindrical casing is provided. The piston is inserted into a cylindrical piston rod slidably provided, and stoppers are fixed at both ends of the piston rod to the control rod at intervals, and two stoppers are provided on a casing wall surface between the pair of pistons. A water pipe and a water pipe are disposed between the two water pipes. The two water pipes communicate with a branch chamber of a cylinder provided in the water control device, which is formed through a piston having a valve body connected thereto. A pilot valve for a water control device, which is connected to a water channel.