JP2753877B2 - Automatic flow control valve device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention discharges water from a reservoir to a downstream river, or
The present invention relates to an automatic flow control valve device that is mounted in a pipeline for supplying water from a reservoir to a field to control the flow rate in order to maintain the amount of water.

(Prior Art) In recent years, with the depletion of water resources, many reservoirs have been constructed. In order to maintain the operation of downstream rivers, it is necessary to discharge a certain amount of water in proportion to the amount of water used.

In the case of field irrigation or the like, the sprinkler is driven by utilizing the water pressure of the reservoir as it is. The pipe channel is used because the water pressure of the reservoir is used.However, if water is used in excess of the amount of water discharged at the most downstream area of this pipe channel, the pipe channel becomes empty. Inhalation of air causes a pulsating flow (water hammer), which hinders water flow, and if the water hammer breaks the pipe channel, there is a danger of causing a flood.

In order to prevent such a situation beforehand, an automatic flow control valve for adjusting the discharge flow rate from the reservoir according to the usage amount is required.

This conventional automatic flow control valve uses a general gate valve, detects a water pressure difference between the upstream side and the downstream side of the gate valve, and makes a predetermined water pressure difference from the water pressure difference and the characteristics of the gate valve. The opening degree of the gate valve is calculated in advance, and the opening degree of the gate valve is electrically operated based on the calculated value.

In a general hydraulic circuit for such an electric automatic flow control valve device, an automatic flow control valve device by itself is used.

One example is shown in FIG. 6 and explained. A pressure difference adjusting piston 2 is provided partially in and out of the flow path 1, and both sides of the pressure difference adjusting piston 2 have a primary pressure P1 and a secondary pressure P2. Pressure difference between the primary side and the secondary side of the flow control valve due to the balance with the elastic force of the spring 4.
Is controlled by itself so that is always constant.

(Problem to be Solved by the Invention) In the above-mentioned conventional automatic flow control valve device, there is the following problem in the case of controlling electrically.

Generally located in the mountainous part of the reservoir or pipe channel, there are few resident observers and there are many lightning strikes. In such a situation, if the electrical system of the automatic flow control valve device breaks down due to a lightning strike, for example, the control becomes impossible, causing a water hammer in the pipeline, breaking the pipeline, and causing a major flood. There is a danger of becoming

In contrast, the self-powered flow control valve shown in FIG.
Although there is no such danger, there are the following problems.

One of the technical problems in discharging reservoir water is to minimize the head loss of automatic flow control valves. The reason is that, for example, if the pressure loss of the automatic flow control valve is 1 kg / cm ² , the height of the levee of the reservoir must be increased by 10 m.

Thus, when the conventional example shown in FIG. 6 is viewed, since the flow path is bent, there is a problem that the pressure loss is increased and the construction cost of the reservoir is greatly increased.

Next, as a second technical problem, the amount of water used for irrigation water is incomparably large compared to the hydraulic circuit. Therefore, as a countermeasure to reduce the pressure loss of the automatic control valve, it is theoretically conceivable to increase the flow path area and reduce the flow velocity, but it is tremendous to increase the bent water channel until the desired pressure loss is achieved. There is a problem that such a valve is not practical because it is a large valve, and such a valve cannot be applied to irrigation water.

A third technical problem is that water discharged from the reservoir is contaminated with waste. From this point of view, the valve shown in FIG. 6 has a problem that the flow path is bent and dust is easily clogged, and when the spring is clogged with dust, self-control cannot be performed.

The present invention has been made in view of the above conventional example,
An object of the present invention is to provide an automatic flow control valve device which can be controlled by itself, has a small head loss, and is not clogged with dust.

(Means for Solving the Problems) A means according to the present invention for solving the above problems is to integrate a space between an outer cylinder and an inner cylinder with a top plate and a bottom plate to form a cavity between the inner cylinder and the outer cylinder. A boss is attached to the center of the inner surface of the lower end of the outer cylinder via a support arm, a support rod inserted into the inner cylinder is screwed to the boss, and the inner cylinder is attached to the support rod. A valve member is formed by fixing a valve body facing the lower end of the valve member, and the valve member is slidably inserted into the casing in the up-down direction, and the lower end is located opposite the upper end of the outer cylinder of the valve member. A gap is provided between the lower end of the inner cylinder and the upper end of the valve body, and the flow path is formed by the gap between the upper end of the inner cylinder and the upper end of the outer cylinder and the lower end of the cap. It is characterized by.

(Operation) With such a configuration, buoyancy is generated in the valve member by the cavity formed between the outer cylinder and the inner cylinder, and the valve member floats in the casing. This floating occurs due to the balance between the pressure difference between the primary pressure (inflow side) received on the bottom plate and the secondary pressure (outflow side) received on the top plate, and the underwater weight (buoyancy) of the valve member. The valve member adjusts the outflow gap between the upper end of the outer cylinder and the lower end surface of the cap by itself while the valve member moves up and down by the pressure.

Next, the flow path is a gap between the upper end of the valve body and the lower end of the inner cylinder,
There is no bent portion formed by the gap between the upper end of the cap and the inner cylinder and the upper end of the outer cylinder.

Even if the dust is clogged, the dust is discharged by the floating of the valve member.

Examples Hereinafter, one example of the present invention will be described in detail. First
In the figure, a discharge port 70 is provided above the cylindrical casing 6.
An annular outflow duct 7 with 1 is connected and an inflow officer 16 is connected at the bottom. The valve member 5 is inserted into the cylindrical casing 6. The valve member 5 will be described in more detail. An inner cylinder 502 having a shorter length than the outer cylinder 501 is concentrically inserted into the outer cylinder 501, and a top plate 503 and a bottom plate 504 are provided at the upper and lower portions of the inner cylinder 502. The inner tube 502 and the outer tube 501 are integrally joined to form a hollow portion 505. A support arm 506 (see FIG. 5) provided radially from the inner surface is provided on the lower inner surface of the outer cylinder 501. The support arm 506 is provided with a boss 507 having a female thread cut along the axis of the outer cylinder 501. It has been fixed. It has a prism 516 at the upper end and a screw 508 at the lower end.
Is inserted into the center of the inner cylinder 502, and the support rod 50
The screw portion 508 at the lower end of the screw 9 is screwed to the female screw of the boss 507 to screw and support the support rod 509. Since the support rod 509 is longer than the length of the outer cylinder 501, the prism 516 protrudes from the upper end of the outer cylinder 501. A valve body 510 is fixed to an upper portion of the threaded portion 508 of the support rod 509, and is opposed to a lower end of the inner cylinder 502. As described above, the valve member 5 includes the outer cylinder 501, the inner cylinder 502, the top plate 503, and the bottom plate 50.
4. A support rod 509 supported via a support arm 506 and a boss 507, and a valve body 501. Upper end 51 of outer cylinder 501
1, upper end 512 and lower end 513 of inner cylinder 501, upper end 514 of valve body 510
It is formed obliquely and reduces water flow resistance.
The valve element 510 has a funnel shape in order to reduce water flow resistance and dirt caught. The lower end of the outer cylinder 501 is provided with a slit 515 that restricts rotation of the stool body 5 and allows vertical movement in the vertical direction. Head 51 of support rod 509
6 is a square pillar as shown in FIG. Reference numeral 6 denotes a casing, into which the outer cylinder 501 of the valve member 5 is slidably inserted, and as shown in FIG. 2, a labyrinth seal portion 517 is formed on the outer periphery of the outer cylinder 501 to prevent water leakage. . Reference numeral 7 denotes an outflow link fixed to the upper end of the casing 6, to which a drain nozzle 701 is connected as shown in FIG. 8
Is a cap facing the upper end of the outer cylinder 501 of the valve member 5 and fixed to the outflow ring 7. The lower end 801 is formed diagonally to reduce water flow resistance. Reference numeral 9 denotes an operation member fitted to the head 516 of the support rod 509 as shown in FIG. This operation stick 10
Is inserted into a hole provided in the guide portion 802 of the cap 8 and is sealed by the casing 802. The operation rod 10 is integrally provided with a screw rod 12 which is screwed into a female screw seat 11 attached to the guide portion 802 of the cap 8, and a handle 13 is provided at an upper end thereof.
Is attached. Reference numeral 14 denotes an opening pointer plate fixed to the handle 13, and reference numeral 15 denotes a scale fixed to the cap 8. Reference numeral 601 denotes a pin which fits into a slit 515 formed at the lower end of the outer cylinder 501 and is provided on the inner surface of the casing 6 as shown in FIG. 16 is an inlet side pipe channel, and 17 is an outlet side channel channel.

Next, the volume of the cavity 505 for giving buoyancy to the valve member 5 will be described. The general hydrodynamic formula gives the total head he
(M) is given by the following equation.

he = h + p / γ + ² / 2g (1) In this equation, he is the total head (m) h is the height from an arbitrary reference plane (m) p is the water pressure (ton / m ² ) γ is the density of water ( 1.0ton / m ³ ) v is flow velocity (m / sec) g is gravitational acceleration 9.8 m / sec ^{2 The} above total head exists at the inlet and outlet of the automatic flow control valve. That is, if the total head of the inlet and the outlet determined by the equation (1) is defined as follows, there is a relationship shown by the following equation between the two.

he ₁ = he ₂ + hγ (2) where he ₁ is the total head at the inlet of the automatic flow control valve (m), and he ₂ is the total head at the outlet of the automatic flow control valve (m). hγ is the automatic flow control valve. (M) From the above equation (2), it is understood that it is desirable to make hγ of the automatic flow control valve as small as possible.

That is, the head loss of the most economical automatic flow control valve is allocated to the height difference between the reservoir and the downstream area determined by the geographical conditions and the total head he planned from the head loss of the pipeline.

For example, if the head loss of the automatic flow control valve is large,
If the height of the reservoir must be increased accordingly and the head loss of the automatic flow control valve is reduced, an extremely large automatic flow control valve is required. The volume V of the cavity 505 is determined based on hγ of the automatic flow control valve assigned in this manner. W = A × hγ × γ (3) where W is the weight (ton) of the valve member 5 in water, and A is the total pressure receiving area (m ² ) of the valve member 5.

In the equation (3), W is obtained by subtracting the buoyancy from the weight G of the valve member 5, and thus is represented by the following equation.

W = G−Vγ = GA × H × γ (4) By substituting the equation (4) into the equation (3), the volume V of the cavity 505 is obtained as follows.

V = G / γ−A × hγ (5) As understood from the equation (5), the volume of the cavity 505 is determined in this manner, and the head loss of the assigned automatic flow control valve is kept constant. It will automatically adjust.

In equation (4), A is approximately equal to the top plate 503 and the bottom plate 5
The actual cavity 505 is designed as the area between the top plate 503 and the bottom plate 504.

Next, the relationship among the water pressure P, the weight G of the valve member 5 and the buoyancy is expressed by the following equation. Substituting equation (4) into equation (3), G−A × H × γ = A × Hγ × γ (6) G + Aγ (−H−Hγ = 0) (7) Both sides of equation (7) When A × P (water pressure acting on the bottom plate 504) is added to the above, G + A (P−Hγ−Hγ · γ) = A × P (8), and the weight G of the valve member 5 + the water pressure acting on the top plate 503 = the bottom plate 504 The hydraulic pressure acting on the valve member 5 is obtained.
Is designed to maintain a balance with the water pressure in the casing 6 and to float while maintaining the loss head Hγ constant.

The operation of the present embodiment having such a configuration will be described below. First, the handle 13 is turned to turn the indicator rod 509, and the valve member 510 is moved up and down to adjust the valve opening H1. The rotation of the handle 13 causes the screw rod 12 screwed into the female screw seat 11 to be screwed.
Also moves up and down, and the opening pointer plate 14 also moves up and down.

Here, for example, the flow rate with respect to the opening degree H1 of the valve element 510 is determined, and the relationship with the vertical movement amount is determined on the opening degree indicator plate 14, whereby the flow rate at that time can be indicated on the scale 15. Since the head 516 of the pointing stick 509 and the operating stick 10 are vertically separated via the operating member 9, the pointing stick 50
By making the screw pitch of the screw rod 12 larger than the screw pitch of the nine screw portions 508, the scale of the scale 15 can be enlarged, and the opening degree of the opening degree H1 is accurately adjusted. After adjusting the opening H1 in this way,
Unless you turn 13, the opening is fixed. Then, the water flowing in from the pipe channel 16 on the inlet side flows into the gap of the opening degree H1,
2 flows from the inside of the inside 2 and the gap of the opening degree H2 to the outflow ring 7 as shown by the arrow. Thus, the flow path has no bent portion, and the end portions 513, 51 in the gap with the opening H1 and the gap with the opening H2.
4, 511 and 512 are formed diagonally to reduce the water resistance, so that the head loss of the so-called automatic flow control valve from the inlet-side pipe channel 16 to the outlet-side pipe channel 17 is reduced. The valve member 5 is floating in the water flow due to the buoyancy of the cavity 505.

Since the top plate 503 and the bottom plate 504 are provided so that the ends of the inner cylinder 502 protrude, a stagnation portion a is formed at this portion. Due to this stagnation part, the dynamic pressure of the water flow does not act on the top plate 503 and the bottom plate 504, and a net hydrostatic pressure is applied to the top plate 503 and the bottom plate 504.

Next, the valve member 5 floats by the balance between the weight G of the valve member 5 and the water pressure acting on the top plate 503 and the water pressure acting on the bottom plate 504 according to the expression (8).

For example, when the amount of water used on the downstream side is too large and the water pressure of the outflow ring 6 (outflow pipe 7) decreases, the water pressure acting on the top plate 503 becomes lower than the water pressure acting on the bottom plate 504. In order to satisfy the condition of the expression (3), the valve member 5 rises, the opening H1 is reduced, the water pressure acting on the top plate 503 is increased, the balance is maintained, and the amount of water on the downstream side is restricted. This allows
Prevent the pipe channel upstream of the automatic flow control valve from being emptied.

Next, conversely, when the amount of water used on the downstream side decreases and the water pressure acting on the top plate 503 increases, the valve member 5 descends to open the opening H2, and the water pressure acting on the top plate 503 decreases. By doing so, a balance that satisfies Expression (8) is achieved.

Similarly, when the water pressure acting on the bottom plate 504 fluctuates due to the fluctuation of the water level of the reservoir, the valve member 5 also rises or falls to adjust the opening H2, and adjust the self-power so as to satisfy the condition of Expression (8). I do.

In this way, the automatic flow control valve controls by itself so that the loss head Hγ is always constant, following the upstream or downstream water pressure fluctuation.

Next, the flow resistance will be described. The inflow area of the opening degree H1 is obtained by multiplying the week length of the inner cylinder 502 (or the valve body 510) by the opening degree H1, and the outflow area is equal to the outer cylinder 501 (or the cap). 8 is multiplied by the opening degree H2, so that the area can be made sufficiently large. Therefore, it is possible to make the inflow and outflow velocities sufficiently low, and to incline the tips 511, 512, 513, 514 and 801 to minimize the hydraulic head loss of inflow and outflow of water. become. Further, since the flow path in the inner cylinder 502 is straight, the head loss is very small.

Next, the problem of garbage will be described. Oversized debris is removed by a dust remover before entering the pipeline from the reservoir. Therefore, the waste flowing into the pipe channel is relatively small waste, and there is no waste that gets caught on the support arm 506.

First, when the opening degree H1 is small and dust is clogged in this portion, the handle 13 can be operated to temporarily widen the opening degree H1 to remove dust. Therefore, it is possible to periodically operate the handle 13 to remove dust.

Next, when dirt is clogged on the outflow side, the water pressure on the outflow side increases, so that the valve member 5 descends to widen the opening degree H2,
Automatically discharge garbage.

(Effects of the Invention) As described in detail above, according to the present invention, the inner cylinder and the outer cylinder are integrally joined by the top plate and the bottom plate to form a cavity, and the valve member can float in the casing, The flow rate can be adjusted by moving the valve body up and down via the support rod, and the opening degree H2 between the cap and the tip of the outer cylinder is adjusted by floating the valve member. Can always be kept constant, so that even if the upstream and downstream water pressures fluctuate, the discharge flow to the downstream can always be kept constant.

Therefore, by providing this automatic flow control valve from the reservoir to the pipe channel main pipe, from this main pipe to the branch pipe, etc., the amount of water used on each downstream side is limited to a constant amount, and the amount of water used on the upstream side of the automatic flow control valve is limited. The pipeline will not be emptied, preventing the water hammer phenomenon and there is no danger of flooding due to the pipeline break. And since it is controlled by itself, there is no possibility that control becomes impossible even if there is a lightning strike.

In addition, since the flow area of the inflow and outflow is widened, the flow velocity is slowed, and the inner cylinder is straight, the head loss can be reduced as much as possible, and the construction cost of the reservoir etc. can be greatly reduced. In addition, since the head loss can be reduced, the size of the automatic flow control valve itself can be reduced, and there is a great economic effect. Since the automatic flow control of a large flow rate can be performed and the clogging of dust can be dealt with, there is an excellent effect as an automatic flow control valve for irrigation.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention, FIG. 2 is a longitudinal sectional view showing the relationship between the outer cylinder and the casing in FIG. 1 in a partially enlarged manner, and FIG. FIG. 4 is a cross-sectional view taken along line BB of FIG. 1, and FIG. 5 is a cross-sectional view taken along line CC of FIG. FIG. 6 is a schematic diagram of a conventional example. 5 Valve member 501 Outer tube 502 Inner tube 503 Top plate 504 Bottom plate 505 Cavity 506 Support arm 509 Support rod 510 Valve body 6 Casing 8 Cap

Claims (1)

(57) [Claims] 1. An outer cylinder and an inner cylinder are integrated by a top plate and a bottom plate to form a cavity between the inner cylinder and the outer cylinder. Attach the boss to
A support rod inserted into the inner cylinder is screwed to the boss, and a valve member is formed by fixing a valve body opposed to a lower end of the inner cylinder to the support rod. Inserted slidably in the up and down direction, provided a cap so that the lower end is located opposite the upper end of the outer cylinder of the valve member, the gap between the lower end of the inner cylinder and the upper end of the valve body, An automatic flow control valve device, wherein a flow path is formed by a gap between an inside of an inner cylinder and an upper end of the outer cylinder and a lower end of the cap.