JPH0428923Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The invention of the present application is a technology related to a water intake gate for a dam or the like, particularly a gate that allows selection of water intake.

[Conventional technology] Since the water level in a reservoir such as a dam fluctuates, the water intake must also be changed to follow these fluctuations. 1
In some cases, a main water intake pipe is provided with multiple intake ports at different heights, but in order to more accurately follow these fluctuations, a selective water intake gate that allows the intake port at the top to be raised or lowered arbitrarily according to the water level is recommended. is appropriate.

The first type of gate to be developed in the past was the independent tower type cylinder gate (Fig. 2 A, B), in which an intake pipe 3a was installed independently in the reservoir, and a winding means 8a was installed directly above it. The top of the water intake pipe is suspended from the water intake pipe, and is raised and lowered as the water level fluctuates, raising and lowering the water intake port 4a in accordance with the water level. Water intake pipe 3
A is surrounded by a tower body 10a, and a screen 11a is stretched all around it.

Figures 3A and 3B are improved plans devised from various restrictions regarding the installation location, in which a steel tower body 10b is erected along the dam body 1b, and a screen 11b is attached to this tower body. Water intake pipe 3 inside the stretched
B is installed vertically so that it can be raised and lowered. Cylinder gates are used as the intake pipes 3a and 3b of both devices, and the lower pipe has a larger diameter than the upper pipe and functions as a sheath pipe, which is inherited from top to bottom. When the apex is lifted up, it is pulled out from the upper tube one by one, and the length as a whole can be extended. Contrary to FIG. 3A, a downwardly converging type cylinder gate in which the diameter of the pipe is larger toward the top has also been put into practical use, but this figure is omitted. This cylinder gate has rectifying plates 7a and 7 on top of the water intakes 4a and 4b.
b are provided respectively to prevent entrainment of air.

Another form is as shown in FIGS. 4A, B and 5A, B, in which a pair of concrete piers 2c, 2d are protruded from the gum support bodies 1c, 1d, respectively, over the entire length of the top and bottom, and these piers This is a method in which the gate is erected by being held between the two. Of these, Figures 4A and 4B show plate-shaped door bodies 12 stacked in multiple stages and connected, fitted into doorstops 9c provided on both sides of a concrete pier 2c, and the top suspended by winding means 8c. . A screen 11c is provided at the tip of the pier to prevent foreign matter from entering.

In the case of Fig. 5A and B, the cylinder gate 3d is sandwiched between the concrete piers 2d, and it rises up and down along the door stop 9d, and passes toward the upstream side through the screen 11d stretched at the front end of the pier. Water is taken from the opened water intake port 4d.

[Problems to be Solved by the Invention] In both of the conventional techniques shown in FIGS. 2 and 3, water can be taken in evenly from all four circumferences since the four circumferences of the water intake pipes are open 360 degrees. However, on the other hand, the equipment costs are high because the intake pipe must be installed independently and the steel tower body 10 must be installed separately to transmit the load acting on the intake pipe to the structure. This would be uneconomical, and since the surfaces of these long-term fixed components are made of steel, it is difficult to repaint them after corrosion, making maintenance difficult as a permanent structure submerged in water.

On the other hand, in the type of gate shown in FIG. 4, the concrete piers are projected on both sides and the gate is sandwiched from both sides, so the tower body is omitted and the above-mentioned problem is solved. However, since the door body is linear, it is heavy and uneconomical. The format shown in Figure 5 was therefore devised. Since this type does not have a rectifying plate, it often causes air to be drawn in. As shown symbolically in Figure 6, there is an air layer between the water intake cross section and the water level, so under certain inflow conditions, air is entrained, and this air flows into the downstream water turbines and pumps. Separation may occur in a rotating body such as a water hammer, causing negative effects such as a decrease in the output and efficiency of a water hammer or a water wheel.

In order to solve the above-mentioned problems, the present invention aims to provide a selective water intake gate that does not use a steel tower body and does not allow air to be entrained during water intake.

[Means for Solving the Problems] The cylinder gate according to the present invention is installed upright between a pair of concrete piers protruding from the structure, and an intake basin is extended on the upstream side of the water intake. The above problem was solved by installing an inflow prevention board on the side of the water body and mounting a rectifying board on the top of the water intake.

[Operation/Embodiment] FIGS. 1A (front view) and B (plan view) show the most preferred embodiment of the present invention.

In the figure, a cylinder gate 3 is sandwiched between concrete piers 2, 2 protruding from a support body 1, and a water intake basin 5 is extended on the upstream side of the water intake port 4, and on the opposite side of the support body. An inflow prevention plate 6 surrounding half the circumference is erected, and a rectifying plate 7 is mounted on the top of the water intake 4. Concrete piers 2 and 2 are erected facing each other, eliminating the need for steel towers, so when viewed as a permanent structure that is constantly submerged in water, there is only a limited amount of consideration given to its maintenance without the risk of further corrosion and deterioration. It is limited only to the door stop part 9).

On the other hand, considering the flow of water, the water temperature in a dam reservoir is generally warm at the surface and suddenly becomes cold from a certain area, and the turbidity is clear at the surface and suddenly becomes turbid from a certain area. It makes sense to take water. However, when concrete pier 2 is erected and the water intake pipe is sandwiched between them,
As shown by B, the condition of uniform inflow from all four circumferences is broken, and it becomes difficult to inflow from the side of the structure 1 or near the concrete pier 2 in a planar manner, which is undesirable because water from deep water is sucked in. In other words, the water depth h ₁ when water is taken from the upstream side, and the water depth when water is taken from the body side.
If h ₂ , then h ₁ < h ₂ .

When the inflow prevention plate 6 is installed upright, it has the feature of canceling out the negative requirements regarding the water intake conditions and producing water intake with a quality comparable to that of equal water intake. By adding a known rectifying plate 7 to this, smooth water intake without allowing air to be drawn in can be continued. Note that the screen 11 shown in the figure is used to prevent foreign matter from getting mixed in, as is the case with known techniques.

[Effects of the invention] As described above, the cylinder gate according to the invention of the present invention has a relatively low construction cost, and has very little aging and accompanying trouble during use, so it can be used for a long period of time. The water intake itself is smooth and even, with no air entrainment, and a significant reduction in downstream troubles can be seen.

[Brief explanation of drawings]

FIGS. 1A and 1B are a front view and a plan view of the embodiment of the present application,
Figures 2A, B to 5A, B show front views A and plan views B of the first, second, third, and fourth prior art techniques, respectively, and Figure 6 shows problems with the prior art. The front sectional view and FIGS. 7A and 7B are a front sectional view A and a plane sectional view B showing the water intake conditions in the prior art. 1...Structure, 2...Concrete pier, 3...
Cylinder gate, 4... Water intake, 5... Water intake tray, 6... Inflow prevention tray, 7... Rectifying plate, 8... Hoisting device, 9... Doorstop section.

Claims (1)

[Scope of utility model registration request] At gates such as dams that are erected between a pair of concrete piers that protrude from the water intake, an intake basin is extended on the upstream side of the water intake, and an inflow prevention plate is erected on the water intake side of the water intake. A cylinder gate characterized by a rectifying plate mounted on the top of the water intake.