JPH11117270A - Gate device for channel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gate device capable of securing a drain flow rate without accumulation of sediment in the neighbourhood of a gate and without enlarging a frontage of the channel side and the gate itself. SOLUTION: A gate main body 4 a base end of which is connected to the river bed side by a hinge mechanism and which is devised free to work to rise and fall by reacting to a water level difference between the channel side and the river side is combined of a faceplate 4a to face the channel side and to seal water to the channel side against the river side, a first float 4c integrally arranged on a part where this faceplate 4a faces the river side and a second float 4d integrally arranged on its head end side. Thereafter, water running toward the river bed side is made to reach the river central side by circulating it around a peripheral surface of the second float 4d and bending it to be a flow along the first float 4c.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gate device provided on a drainage gutter or a gutter pipe between a river and, for example, an agricultural waterway, etc., and more particularly to an apparatus which operates according to a water level difference between a waterway side and a river side. The present invention relates to a float type waterway gate device for preventing backflow of water from a river.

[0002]

2. Description of the Related Art As a gate device provided on a drain gutter or a gutter tube, a float type gate device has been widely used. In this float type gate device, a hollow gate body whose dimensions are matched to the channel cross section on the water channel side is arranged at the boundary between the water channel side and the river, and the lower end of the gate main body is vertically moved by a hinge. It is made rotatable.
The basic configuration is such that the gate body is raised and lowered around the hinge by utilizing buoyancy caused by a difference in water level between the water channel side and the river side.

[0003] In such a float type gate device, the gate body is raised and lowered by buoyancy by water,
Compared to an undulating gate whose operation is controlled by a conventional drive mechanism, a significant improvement has been achieved in that the equipment is simple and no artificial operation is required at all.

FIG. 6 is a schematic sectional view showing the undulating operation of a gate body in a conventional float type gate device.

As described above, the base end of the gate body 51 having a hollow inside is connected by a hinge mechanism formed by the hinge bracket 50 and the pin 52 fixed to the water channel side. It is rotatable in the direction. Sealing packings (not shown) are provided on the base end side and both end edges in the width direction of the gate main body 51, respectively. When the gate main body 51 is in the upright posture, these packings are located at the bottom of the water channel. In addition, it can be sealed in close contact with the left and right side walls.

The gate body 51 is advantageously of a relatively simple shape in order to simplify its manufacture and reduce costs. However, the gate body 51 has an outer shape such that a predetermined buoyancy is applied particularly when the gate body 51 stands up. It is necessary to. When the width of the channel is small, the width of the gate body 51 is also small.
Has to be increased in the thickness direction.

[0007] In view of the design background of the gate body 51, as shown in the figure, a hollow flat box-shaped main portion 51 a and a clevis integrally connected to the base end thereof and connected to the pin 52. It is effective to manufacture the portion 51b separately from each other. In this case, if the main portion 51a is assembled in a rectangular shape as a frame as a flat frame material and the face plates facing the river side and the waterway side are connected to these frame materials, respectively, the manufacturing is simplified and the cost is high. It is also possible to have rigidity.

[0008]

When the main portion 51a has such a flat box shape, the tip of the gate body 51 has a substantially rectangular profile, and the bulk of the gate body 51 in the thickness direction is increased. Therefore, the tip surface is a surface that extends long in the streamline direction from the water channel side to the river side.

However, if the tip of the main portion 51a is angular and the tip end surface is long in the streamline direction, earth and sand easily accumulate on the hinge mechanism portion, and eddy currents generated at the tip portion of the main portion 51a. This causes obstacles such as an increase in flow resistance.

FIG. 6A shows a state in which the water level on the water channel side is higher than the water level on the river side, and the gate body 51 has a load that is tilted down by water from the water channel side and the buoyancy due to the water level on the river side. Is kept in a balanced state. At this time, the water from the water channel flows down around the tip of the main portion 51a of the gate main body 51 at a flow velocity substantially proportional to the difference in water level with the river side. At this time, since the main portion 51a is angular and the front end surface has a certain length in the streamline direction, the streamline of water passing over the gate main body 51 is substantially straight so as to follow the front end surface of the main portion 51a. Laminar flow close to.

With such a water stream line, a flow field is less likely to be generated in the direction of the surface where the gate body 51 faces the river side and is inclined obliquely downward. The middle part is a stagnation point. Therefore, the gate body 51
When the earth and sand S flows into the base end side for some reason, the earth and sand S is included in the stagnation point and accumulates as it is. For this reason, when the amount of sediment S increases and comes close to the attitude of tilting the gate body 51 horizontally, the gate body 51 moves when the water level on both the water channel side and the river side is low. Can not be done.

As shown in FIG. 2B, when the water level on the channel side is high and the flow velocity of the water toward the river side is high, the surface where the main portion 51a faces the channel and the front end surface are at a right angle. Vortex, the vortex V is generated as a result of this bend resulting in a streamline that separates the streamline from the tip end surface.

The vortex V acts as a resistance to the water flow from the water channel side, so that the flow rate from the river side is reduced. Therefore, in order to discharge water to the river side so as to match the expected water amount on the waterway side, it is necessary to increase the width dimension of the waterway, and accordingly, the gate body 5 is required.
1 must also be enlarged. Further, due to the resistance due to the eddy current V, the difference in water level between the water channel side and the river side with the gate body 51 as a boundary also increases.

As described above, in a conventional gate device having a backflow preventing function using a conventional gate body having an angular tip end,
In addition to the failure of the gate opening operation due to the accumulation of sediment, there is a problem that it is necessary to increase the width of the water channel under construction conditions where the maximum water level on the water channel side frequently increases.

The problem to be solved in the present invention is to provide a gate device which can secure a drain flow rate without accumulation of sediment near the gate and without increasing the width of the waterway side and the gate itself.

[0016]

SUMMARY OF THE INVENTION The present invention is arranged at a boundary between a water channel and a river, and its base end is connected to a river bed side by a hinge mechanism, and is raised in response to a water level difference between the water channel side and the river side. In the gate device capable of inverting operation, it is characterized in that the tip portion of the gate main body, in which the water flowing from the water channel side to the river side circulates, as a profile that circulates the flow along the surface facing the river side of the gate main body. And

In this configuration, the profile at the tip of the gate body can be a circumferential surface having an axis substantially perpendicular to the streamline of water flowing from the water channel side to the river side.

A face plate facing the water channel side and sealing the water channel side against the river side; and a first float integrally disposed at a portion where the face plate faces the river side.
The first float has a combination with a second float integrally disposed on the distal end side of the first float, the second float having an axis substantially perpendicular to a streamline of water flowing from a waterway side to a river side, and having a first float. A hollow cylindrical shape having an outer diameter equal to or greater than the thickness may be used.

In the case of this configuration, the outer diameter of the second float is at least 300 mm, preferably about 300 to 450 mm.

[0020]

FIG. 1 is a longitudinal sectional view showing a main part of a gate device for preventing backflow according to the present invention, and FIG. 2 is a longitudinal sectional view taken along line AA of FIG.

In the figure, a water channel is formed by a bottom plate 41 constructed as a bank, left and right side plates 42, 43 and a top plate 44, and a stay 1 is fixed on the bottom plate 41 between the side plates 42, 43. ing. At the both ends of this stay 1, a side panel 4
A pair of liners 2, 3 protruding to the river side with a part of their backs lined to 2, 43 are provided, and a gate body 4 which can be vertically moved between these liners 2, 3 is arranged. ing.

The gate body 4 has a face plate 4a having a width slightly smaller than the distance between the liners 2 and 3 and facing the water channel, a clevis 4b integrally connected to an end of the face plate 4a, It is provided with a hollow float 4c disposed on the front side of the face plate 4a, and a head float 4d integrally provided on the tip side of the float 4c. In this embodiment, the float 4c corresponds to the first float, and the head float 4d corresponds to the second float.

The face plate 4a has a length from the lower end of the clevis 4b to the float head 4d, and has a lower packing 5a on the lower end side for water sealing between the stay 1 and the left and right end edges. Liners 2 and 3 all around
Packings 5b, 5 that allow the surfaces of the parts to slide in a watertight manner.
c. The clevis 4b is connected to a bracket 1a provided on the stay 1 by pin bonding to form a hinge mechanism together with the bracket 1a.

The float 4c is formed in a flat hollow box shape, and the head float 4d is made of a pipe material and has a hollow structure by closing both ends in the axial direction with face plates. These floats 4c
The head float 4d has a total internal volume so that the gate body 4 can be held in the standing posture shown in FIG. 2 by buoyancy caused by rising of the water level on the river side.

The axis of the head float 4d can be set horizontally by using a pipe material so that the axis of the head float 4d is perpendicular to the direction in which the gate body 4 is tilted. Therefore, the water from the water channel side is discharged to the river side as a flow around the peripheral surface orthogonal to the axis of the head float 4d.

In the above configuration, as shown in FIG.
When the river water level H on the river side is higher than the water level h in the channel in the embankment, the buoyancy received by the float 4c and the head float 4d by the water on the river side pushes the gate body 4 counterclockwise around the hinge mechanism in FIG. And the face plate 4a
Packing 44a provided on the front edge of the roof 44 with its back surface
Rotate until it hits. Due to the posture of the gate body 4, the lower packing 5 a seals the space between the stay 1 and the left and right liners 2 and 3, and the side packings 5 b and 5 c seal the water. Backflow is prevented.

On the other hand, as shown in FIG. 3, when the water level h in the channel becomes higher than the river water H, the pressure applied to the entire face plate 4a from the water in the channel causes the float 4c and the head float 4d to move toward the river side. It becomes dominant over the buoyancy received from the water, whereby the gate body 4 starts to rotate clockwise around the hinge mechanism. Therefore, the water in the water channel is discharged to the river side, and this discharge is maintained without the backflow of water from the river side. And the water level h in the canal is shown in FIG.
2, the gate body 4 rotates counterclockwise due to the buoyancy received from the river and returns to the state shown in FIG.

Further, as shown in FIG. 4, if the water level h in the channel and the river water level H are both lower and the water level h in the channel is higher than the river water level H, the gate body 4 will fall in the same direction as in the example of FIG. The water can be discharged from the water channel to the river side.

In the raising / lowering operation of the gate body 4, when the gate body 4 is open, all the water on the water channel side flows around the peripheral surface of the head float 4d, and flows from the space between the liners 2 and 3. No leakage. Since the peripheral surface of the head float 4d forming the upper end of the gate main body 4 has an arc shape, a flow toward the front surface of the float 4c is promoted along this arc.

FIG. 5 is a schematic view of the flow of water from the water channel side by such a head float 4d. As shown in FIG. 5A, the flow along the arc surface of the head float 4d is gentle downward. Therefore, the flow of this bending becomes a flow along the front surface of the float 4c as a history. Then, since the flow along the float 4c is a continuous flow toward the river bottom on the base end side of the gate body 1, the continuous flow creates a flow field in the river bottom portion away from the waterway side.
Therefore, in the conventional structure, soil and the like are likely to remain deposited on the river bottom or in the water channel near the base end of the gate body 1, while flowing from the front end side of the gate body 1 to the base end side to the central side of the river. Since the stagnation point can be eliminated depending on the location of the flow, the accumulation of sediment can be prevented.

FIG. 5B shows a state in which the water level h in the channel and the river water level H are both high and water is discharged from the channel. Under such conditions, the flow velocity of the water around the head float 4d at the tip of the gate main body 1 becomes large, and if it has an angular shape as in the conventional structure, a large eddy current is generated due to separation of the flow. However, in the present invention, the head float 4d has an arc-shaped profile.
Since a laminar flow along the peripheral surface of d can be maintained, the generated eddy current can be suppressed to a small value.

Therefore, the vortex does not cause a large resistance to the flow of water from the water channel side to the river side, and the discharge flow rate is not restricted. Therefore, it is not necessary to compensate for the flow rate by increasing the interval between the side panels 42 and 43 or to increase the width of the gate body 4, and it is possible to mass-produce the gate body 4 without increasing the specification of the size and shape. Become.

When the head float 4d having an arc surface is provided as described above, it is possible to prevent sediment accumulation and secure a discharge flow rate.
It is preferable to set it to about 00 to 400 mm. That is, since the discharge amount and the flow velocity of the water from the water channel fall within a certain range, the outer diameter of the head float 4d of such a degree suppresses the generation of the vortex on the peripheral surface and the streamline toward the base end. This is preferable in terms of both promotion of wraparound.

Further, the float 4c is a flat hollow box, and if ribs and the like are disposed inside the float 4c, the overall rigidity can be increased, but the increase in weight affects the buoyancy. Cheap. On the other hand, since the head float 4d using a pipe material has a circular cross section and thus has a greater durability against an external force load than a flat box-shaped one, if the head float 4d is integrally joined to the float 4c, The reinforcement structure can be obtained also for the float 4c. The head float 4d occupies substantially the entire length of the gate body 4 in the width direction, and protrudes toward the river more than any other portion in any posture. For this reason, although the boulders and the like of the river and the like are likely to collide with each other, it is possible to provide the equipment having durability against external force due to the high strength due to the circular cross section of the head float 4d.

[0035]

According to the first aspect of the present invention, the flow of water flowing from the water channel side to the river side is circulated as a flow along the surface of the gate body facing the river side. A flow field toward the center can be created, and sediment and the like can be prevented from being deposited near the base end of the gate body. Therefore, the gate body can be fully opened even when the water level is low, and the opening operation does not fail.

According to the second aspect of the present invention, a flow field heading toward the center of the river can be created between the gate body and the riverbed only by forming the tip of the gate body in a circumferential shape. It simplifies the design and fabrication of the body and does not add unnecessary resistance to flow.

According to the third aspect of the present invention, it is possible to prevent the accumulation of earth and sand near the base end of the gate body as in the first aspect of the present invention, so that there is no occurrence of a defective opening operation. Even if the flow velocity of the water flow is high, the flow can be made to flow down as a laminar flow around the second float, so that the generation of a large vortex is suppressed. Therefore, the resistance to water from the water channel side can be reduced, and no measures such as increasing the width of the water channel or lengthening the width of the gate body for flow rate compensation are required.

According to the fourth aspect of the present invention, by optimizing the outer diameter of the second float, it is possible to more reliably prevent the accumulation of earth and sand and the generation of a vortex.

[Brief description of the drawings]

FIG. 1 is a front view illustrating a main part of a gate device according to an embodiment.

FIG. 2 is a longitudinal sectional view taken along line AA of FIG.

FIG. 3 is a schematic longitudinal sectional view showing a start time of drainage of water from a water channel side.

FIG. 4 is a schematic longitudinal sectional view showing tilting of a gate body when water levels on a water channel side and a river side are low.

FIG. 5 is a diagram showing a behavior of a flow of water around a head float having an arc-shaped outer peripheral surface.

FIG. 6 is a view showing the behavior of water flow in the case of a conventional gate body having an angular tip.

[Explanation of symbols]

 1 Stay 2, 3 Liner 4 Gate body 4a Face plate 4b Clevis 4c Float (first float) 4d Head float (second float) 5a Lower packing 5b, 5c Side packing 41 Bottom board 42, 43 Side board 44 Top board

Claims (4)

[Claims] 1. A gate device which is disposed at a boundary between a waterway and a river, and whose base end is connected to a riverbed side by a hinge mechanism and which can be raised and lowered in response to a water level difference between the waterway side and the riverside. A waterway gate device serving as a profile for circulating a portion of the front end portion of the gate body where water flowing from the waterway side to the river side circulates along a flow along a surface of the gate body facing the river side. 2. The waterway gate device according to claim 1, wherein the profile at the tip of the gate body is a circumferential surface having an axis substantially orthogonal to a streamline of water flowing from the waterway side to the river side. 3. A gate device which is arranged at a boundary between a waterway and a river, has its base end connected to the riverbed side by a hinge mechanism, and is capable of performing a tilting operation in response to a water level difference between the waterway side and the riverside. A face plate facing the waterway side to seal the waterway side against the river side, a first float integrally disposed at a portion where the faceplate faces the riverside, and the first float And a second float integrally disposed at the tip end of the first float, the second float having an axis substantially perpendicular to a streamline of water flowing from the waterway side to the river side and having a first float.
A water channel gate device having a hollow cylindrical shape having an outer diameter not less than the thickness of the float. 4. The outer diameter of the second float is at least 30.
The waterway gate device according to claim 3, which is set to 0 mm.