Water intake panel and method for manufacturing water intake panel

Abstract

To provide a water intake panel having high strength and capable of ensuring a sufficient amount of water intake even when the flow velocity is high, and a method for manufacturing the same. [Solution] A water intake panel 10 is placed at an angle at the intake port for flowing water. It comprises a rectangular frame 11 made up of left and right side members 11a, 11b and upper and lower end members 11c, 11d, and a screen 12 attached to the frame 11. The screen 12 comprises multiple rods 14 spanning between the upper and lower end members 11c, 11d and multiple wedge wires 15 extending in the left-right direction and fixed to the rods 14. The wedge wires 15 have a cross section shaped like an inverted triangle that is long vertically and are fixed to the rods 14 at their lower vertices T while tilted forward by 5 to 6 degrees, and the downstream corner P1 of the base B of the wedge wires 15 is arc-shaped with a radius r1 of 0.1 to 1.0 mm.

Description

[Technical Field]

[0001] The present invention relates to a water intake panel and a manufacturing method thereof, and more particularly to an improvement in a water intake panel that is placed in an inclined state at a flowing water intake port, and a manufacturing method thereof. [Background technology]

[0002] Patent Document 1 (Figs. 3 and 4) discloses an inclined screen (water intake panel) for mountain stream water intake, which includes support rods that extend in the direction of flow and are supported by a rectangular frame, and multiple wedge wires that are supported by the support rods. The wedge wires have an inverted triangular cross section, and gaps are provided between adjacent wedge wires that allow water to pass through but prevent fallen leaves and sand from passing through. Patent Document 1 also describes installing the wedge wires at an inclination angle of 5° elevation and depression.

[0003] Figure 1 of Patent Document 2 and paragraph

[0021] of the specification disclose a screen unit (water intake panel) in which a screen made up of wedge wires and rods supporting them is curved in an S-shape in side view. Furthermore, it also describes that when the width of the upper side of the cross-sectional shape of the wedge wires is 3 mm and the height is 5.5 mm, it is preferable that the distance between adjacent wedge wires (slit width, filter gap) is 1 to 2 mm.

[0004] Paragraphs

[0003] and

[0004] of Patent Document 3 describe a method for manufacturing a running water screen in which a wedge wire is wound spirally around cylindrically arranged rods to form a cylindrical screen, and then the wedge wire is cut to open the screen flat. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-173957 [Patent Document 2] Japanese Patent Publication No. 2022-38981 [Patent Document 3] Special Publication No. 2005-508726 Summary of the Invention [Problem to be solved by the invention]

[0006] The smaller the filter gap of the screen, the smaller the sand particles that can be removed by the screen. On the other hand, a small filter gap reduces the amount of water taken from the screen. The water intake screens in Patent Documents 1 and 2 have inverted triangular wedge wires arranged at an angle, so despite the small filter gap, there is little resistance to water flow within the gap. Furthermore, the adjacent downstream wedge wires receive the surface water flow and introduce the water into the filter gap, allowing for a large amount of water to be taken in.

[0007] However, with the filters of Patent Documents 1 and 2, when the flow rate is high, the flowing water tends to pass through the gaps between the wedge wires, resulting in a low water intake volume. Furthermore, when the flow rate is high, the force exerted by the flowing water on the water intake panel is large, making it difficult to maintain its strength. The present invention aims to provide a water intake panel that can ensure a sufficient water intake volume even when the flow rate is high, and to provide an efficient method for manufacturing such a water intake panel.

[0008] Another object of the present invention is to provide a water intake panel with high strength that can stably receive water flow even when the flow rate is high, and a method for manufacturing the same. [Means for solving the problem]

[0009] The water intake panel 10 of the present invention is a water intake panel 10 that is placed in an inclined position at a flowing water intake port, and comprises a rectangular frame 11 consisting of left and right side members 11a, 11b and upper and lower end members 11c, 11d, and a screen 12 attached to the frame 11. The screen 12 is made up of a plurality of rods 14 that are stretched between the upper and lower end members 11c, 11d, and a plurality of wedge wires 15 that extend in the left-right direction and are fixed to the rods 14. The wedge wires 15 have a cross section that is long in the vertical direction and are fixed to the rods 14 at their lower vertex T in a state inclined forward by 5° to 6°, and the corner P1 at the front end of the base B of the wedge wire is arc-shaped with a radius r1 of 0.1 to 1.0 mm.

[0010] In such a water intake panel 10, it is preferable that the corner P2 at the rear end of the base B of the wedge wire 15 is arc-shaped with a radius r2 that is substantially the same as the radius r1 of the corner P1 at the front end. It is also preferable that the frame 11 and the rod 14 are curved so as to be convex downward.

[0011] A second embodiment of the water intake panel 10 of the present invention is a water intake panel 10 that is placed at an inclined position at a flowing water intake port, and comprises a rectangular frame 11 consisting of left and right side members 11a, 11b and upper and lower end members 11c, 11d, and a screen 12 attached to the frame 11, the screen 12 comprising a plurality of rods 14 stretched between the upper and lower end members 11c, 11d and a plurality of wedge wires 15 extending in the left-right direction and fixed to the rods 14, the wedge wires 15 having a cross section in the shape of an inverted triangle that is long vertically and fixed to the rods 14 at their lower vertices T in a state tilted forward by 5° to 6°, and a reinforcing bar 13 having a thickness approximately equal to or less than the diameter of the rod 14 is fixed to the underside of at least one of the plurality of rods 14.

[0012] The method for manufacturing a water intake panel of the present invention is characterized by arranging a plurality of rods 14 in a cylindrical shape with a gap between them, spirally winding and fastening a wedge wire 15 around the outer periphery of the rods 14 while tilting it at an angle of 5 to 6 degrees to form a cylindrical screen 16, cutting the wedge wire 15 along the space between two adjacent rods 14, opening the cylindrical screen 16 from the cut end, and attaching and fixing it to a rectangular frame 11 while holding it in a flat or curved shape against the elastic restoring force of the wedge wire 15.

[0013] In the manufacturing method of such a water intake panel 10, after fixing the screen 12 to the frame 11, it is preferable to fix a reinforcing bar 13 having a thickness approximately equal to or less than the diameter of the rod 14 to the underside of at least one of the multiple rods 14. [Effects of the Invention]

[0014] In the water intake panel of the present invention, the radius of the corners at the front end of the base of the wedge wire is 0.1 to 1.0 mm, so the water flowing along the upper surface of the base flows along the corners at the front end (the so-called Coanda effect), and with the negative pressure generated in the gap, it is drawn directly into the gap. Therefore, even if the slot width is small, a large amount of water can be taken in.

[0015] In such a water intake panel, if the radius of the rear corner of the base of the wedge wire is substantially the same as the radius of the front corner, it is easy to manufacture and maintain because it is symmetrical. Also, if the frame and rod are curved so that they are convex downward, the water intake panel will have a three-dimensional structure and will be stronger.

[0016] In a second aspect of the water intake panel of the present invention, a reinforcing bar having a thickness approximately equal to or less than the diameter of the rod is fixed to the underside of at least one of the multiple rods, thereby increasing the strength of the water intake panel without reducing the amount of water intake.

[0017] The method for manufacturing water intake panels of the present invention involves arranging multiple rods at intervals in a cylindrical shape and then spirally winding and fastening a wedge wire around the outer periphery of the rods at an angle of 5 to 6 degrees to form a cylindrical screen, thereby enabling efficient and accurate cylindrical screen manufacturing. Furthermore, the wedge wire is attached and fixed to a rectangular frame while being held flat or curved against the elastic restoring force of the wedge wire, so the panel remains elastic even after being attached to the frame. This creates tension in the water intake panel, helping to increase its strength.

[0018] In such a method of manufacturing a water intake panel, if a reinforcing bar with a thickness approximately equal to or less than that of the rod is fixed to the underside of at least one of the multiple rods after it is fixed to the frame, the resistance to deformation against external forces will be increased without reducing the amount of water intake. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1A is a partially omitted front view showing one embodiment of a water intake panel of the present invention, and FIG. 1B is a cross-sectional view taken along line II in FIG. 1A. [Figure 2] 2A is a cross-sectional view taken along line II-II in FIG. 1B, and FIG. 2B is an enlarged view of a main part thereof. [Figure 3] FIG. 1C is an enlarged view of part III in FIG. 1B. [Figure 4] FIG. 1B is a schematic perspective view of the water intake panel of FIG. 1A. [Figure 5] FIG. 1C is an enlarged view of a main part of the water intake panel of FIG. 1B. [Figure 6] FIG. 7 is an explanatory diagram showing the operation of the water intake panel of FIG. 6. [Figure 7] FIG. 10 is an enlarged view of a main portion showing another embodiment of the water intake panel of the present invention. [Figure 8] 1 is a process diagram showing one embodiment of a method for manufacturing a water intake panel of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] [Water intake panel configuration] The water intake panel 10 shown in Figures 1A and 1B includes a rectangular frame 11 made up of left and right side members 11a, 11b and upper and lower end members 11c, 11d, and a screen 12 attached to the frame 11. The frame 11 is installed at an incline that gradually descends from the upstream side to the downstream side. The inclination angle θ° is preferably approximately 30° to 50°, with approximately 40° providing the highest water intake efficiency. At an angle of 30°, water intake efficiency increases, but runoff tends to accumulate on the screen. In this embodiment, as shown in Figures 1B and 2, a reinforcing bar 13 of the same shape as the side members 11a, 11b is provided between the side members 11a, 11b.

[0021] The side members 11a, 11b and the reinforcing bar 13 are made of downwardly curved flat bars. The flat bars preferably have a thickness of approximately 3.5 to 4.5 mm and a width of approximately 45 to 55 mm. The thickness of the reinforcing bar 13 is approximately equal to or less than the diameter of the rods 14 that make up the screen 12. This prevents the reinforcing bar 13 from reducing the aperture ratio, ensuring sufficient water intake. The length (effective length) of the rod screen 12 is, for example, approximately 1000 to 2000 mm, and the width is, for example, approximately 500 to 1000 mm. The radius of curvature of the screen is approximately 1000 to 3500 mm, particularly approximately 2000 to 3500 mm. The difference K1 between the straight line (chord) K drawn from the top to bottom of the screen 12 and the center of the arc of the screen 12 is approximately 50 to 90 mm (when the chord length is 1200 mm), particularly approximately 58 to 62 mm. The width of the screen 12 is approximately 1200 to 1600 mm. If the width of the screen 12 is narrow, the reinforcing bars 13 may be omitted. The upper ends of the side members 11a and 11b are fixed to the left and right ends of the upper scrap member 11c by welding or the like, and the lower ends are fixed to the left and right ends of the lower scrap member 11d by welding or the like. The frame 11 and reinforcing bars 13 can be manufactured by pressing or the like from a thin plate of stainless steel such as SUS304.

[0022] As shown in Figures 1A and 2, the upper end of the reinforcing bar 13 and the upper scrap material 11c are connected by screws or the like via angles 13a. They can also be connected by welding or the like. The lower end of the reinforcing bar 13 and the lower scrap material 11d are similarly connected by screws or the like. Furthermore, on the downstream side of the lower scrap material 11d, a base material 13b made of angle iron (angle) that supports the entire water intake panel 10 is attached. It is preferable that the base material 13b be provided on the back side of the screen 12 so as not to obstruct the flowing material. In this embodiment, the base material 13b is fixed to the concrete body 13d or the like by anchor bolts 13c or the like.

[0023] The screen 12 is a net-like member made up of a number of rods 14 extending in the vertical direction and fixed at the top and bottom ends to the scraps 11c, 11d, and a number of wedge wires 15 extending in the horizontal direction on the upper surfaces of the rods 14, i.e., extending so as to intersect with the rods 14 and fixed onto the rods 14. The opening ratio of the screen 12 is, for example, about 15 to 20%, and particularly about 16 to 18%.

[0024] The rods 14 are made of wire rods with diameters of approximately 3 to 6 mm, particularly 3.2 to 4 mm. They are arranged horizontally at intervals of approximately 8 to 40 mm, with their upper and lower ends fixed to the upper scrap material 11c and the lower scrap material 11d, respectively, by welding or other means. The rods 14 at the left and right ends are further fixed to the upper surfaces of the left and right side members 11a and 11b by welding or other means. The cross-sectional shape of the rods 14 is typically circular. This allows for the use of commercially available wire rods and simplifies handling during manufacturing. The rods 14 are preferably arranged at equal intervals. While there is no particular limit to the number of rods 14, typically there are approximately 40 to 60 rods per meter; for example, a 400 mm-wide screen 12 has approximately 15 to 25 rods. In Figure 2A, a total of 21 rods 14 are used. The rods 14 are preferably made of a weather-resistant material such as stainless steel, e.g., SUS304.

[0025] The screen 12 is generally flat overall, but is flexible and its shape is not fixed (see FIG. 8). As shown in FIGS. 1B and 4, when it is fixed to the frame 11, it takes the form of a curved surface that is convex downward. However, depending on the shape of the frame 11, it can also be flat or curved upward. The screen 12 is supported by upper scrap material 11c, lower scrap material 11d, left and right side materials 11a and 11b, and base material 13b.

[0026] As shown in FIGS. 1B and 3B, the wedge wire 15 is a wire fixed onto the rod 14 so as to intersect with the rod 14 at a distance from each other. As shown in FIG. 5, the wedge wire 15 has a vertically elongated inverted triangular cross section, and in this embodiment, the corners, i.e., corners P1 and P2 at the front end (downstream side) and rear end (upstream side) of the base B, and the apex T at the lower end are rounded. The apex T at the lower end is fixed to the rod 14 while tilting forward by 5 to 6 degrees downstream. In FIG. 5, the left side is the upstream side, and the right side is the downstream side.

[0027] The width N of the wedge wire 15 is limited to 1.5 to 4 mm when spirally winding it around a cylindrically arranged rod array, but is preferably about 2 to 3 mm, particularly about 2.2 to 2.4 mm. The height H is about 2.5 to 11 mm, preferably about 3.5 to 8 mm, particularly about 3.3 to 3.7 mm. The forward tilt angle θ is optimally 5° to 6° from the viewpoint of water intake efficiency and the winding process. Although manufacturing is possible with angles smaller than 5°, welding becomes complicated, and angles greater than 6° result in a decrease in water intake efficiency. The slot width S, which is the distance between adjacent wedge wires 15, 15, is preferably about 0.3 to 1.0 mm, more preferably about 0.5 to 1.0 mm. If it is smaller than 0.1 mm, manufacturing becomes complicated, and if it is larger than 1.0 mm, it is prone to clogging with sand and other particles. The slot width S depends on the measurement method, but here it is defined as the narrowest width in the direction perpendicular to the water flow.

[0028] In this wedge wire 15, the radius r1 of the downstream corner P1 of the base B of the inverted triangle is preferably about 0.1 to 1.0 mm, and more preferably about 0.5 to 0.8 mm. Furthermore, although the radius r1 depends on the size of the slot width S, it is preferably 0.6 times or more the slot width S, and more preferably 0.8 times or more. In this embodiment, the rear end (upstream side) corner P2 of the base B is also rounded with a radius r2 that is substantially the same as the radius r1 of the front end corner P1. However, it may also be rounded with a smaller radius (see FIG. 7). The vertex T of the inverted triangle fixed to the rod 14 is rounded with a radius larger than the corners P1 and P2 of the base B.

[0029] The wedge wire 15 can be manufactured by drawing a stainless steel wire with a circular cross section through a die with a predetermined cross-sectional shape. Typically, the wire is passed sequentially through multiple dies with different shapes. The wedge wire 15 is preferably made of a weather-resistant material such as stainless steel SUS304. By increasing the radii rt of the downstream corner P1, the upstream corner P2, and the vertex T of the cross section of the wedge wire 15, the cross section becomes closer to a circle, facilitating the drawing process.

[0030] [Usage and function of water intake panels] Next, referring to Figure 6, we will explain how to take water from a river using this water intake panel 10. The water intake panel 10 is placed so as to block a water intake port (not shown) located in the center of the river. As a result, a portion (lower layer) W1 of the water Wa flowing from upstream collides with the wedge wire 15 on the downstream side, is taken in through the gap G in the wedge wire 15, and is drawn into the gap G. At this time, negative pressure is generated in the gap G, and this negative pressure draws in the water even more strongly. The other portion (upper layer) Wa2 passes over the wedge wire 15 on the downstream side and flows downstream.

[0031] At this time, because the corner P1 at the front end of the base B of the wedge wire 15 has an arcuate shape with a radius of 0.1 to 1.0 mm, a portion Wa1 of the water Wa flowing from upstream flows downward while adhering to the curved surface of the corner P1 at the front end (the Coanda effect). It is then drawn directly into the gap G. Therefore, even if the slot width S is small, a large amount of water can be taken in. Moreover, because the slot width S is small, debris such as leaves and sand can be efficiently removed.

[0032] The water Wa2 that is not sucked into the gap G flows downstream along with floating debris such as leaves and sand. It then flows over the corner P2 at the rear end of the wedge wire 15 immediately below, along the upper surface (base B of the triangle), and some of it, Wa1, flows further into the next gap G. In this embodiment, the frame 11 is curved convexly downward, so the inclination angle of the wedge wire 15 is large on the upstream side and becomes gentler as it moves downstream. However, this change is slight, so it has almost no effect on the amount of water intake. However, the water intake rate tends to be somewhat lower upstream due to the fast flow, and somewhat higher downstream.

[0033] In this embodiment, the radius of the corner P2 at the rear end (upstream side) of the base B of the wedge wire 15 is substantially the same as the radius of the corner P1 at the front end (downstream side). The width of the gap G between the wedge wires 15 is narrowest at a position somewhat further back. This increases the water flow speed, fully demonstrating the effect of drawing in water Wa. Furthermore, because the frame 11 and rod 14 are curved so as to be convex downward, the water intake panel 10 has a three-dimensional structure and is strong. The water Wa that falls through the gap G between the wedge wires 15 is supplied to a water supply facility or the like from a water intake port (not shown) located below the water intake panel 10.

[0034] [Water intake panel manufacturing method] Next, an embodiment of a method for manufacturing the water intake panel 10 will be described with reference to Figure 8. First, a plurality of rods 14 are arranged in a cylindrical shape with a spacing S between them (arrangement step S1). Next, a single wedge wire 15 is spirally wound at an equal pitch around the outer periphery of the rods 14 with a small gap G and tilted at an angle of 5 to 6 degrees relative to the rods 14, and secured to the rods 14 to form a cylindrical screen 16 (cylinder formation step S2). A plurality of wedge wires 15 may be spirally wound. The wedge wire 15 is preferably secured to the rods 14 by welding such as electric resistance welding. The welding is performed in the order in which the wedge wire 15 comes into contact with the rods 14.

[0035] Next, the wedge wire 15 is cut sequentially along the gap between two specific adjacent rods 14, and the cylindrical screen 16 is opened on both sides from the cut ends (cutting step S3). This results in a flat or curved screen 12. When the wedge wire 15 is cut, the screen 12 tends to expand or curl due to its elastic force. For this reason, the outer periphery or cut ends of the screen 12 are held to support it against the restoring force. Then, while holding the screen 12 against the elastic restoring force of the wedge wire 15, it is expanded into a flat or curved shape and attached to the rectangular frame 11 and fixed (fixing step S4).

[0036] The frame 11 is preassembled with left and right side members 11a, 11b, upper and lower end members 11c, 11d, and a reinforcing bar 13. The side members 11a, 11b and the end members 11c, 11d are fastened together by welding or screws, and the reinforcing bar 13 is fastened with screws. To fasten the screen 12 to the frame 11, rods 14 at the left and right ends of the screen 12 are welded to the top surfaces of the left and right side members 11a, 11b, and the central rod 14 is welded to the top surface of the reinforcing bar 13. The reinforcing bar 13 may be pre-fixed to the underside of one of the rods 14 by welding or other means. The upper and lower ends of the other rods 14 are then welded to the upper and lower end members 11c, 11d to integrate the entire structure. This results in a water intake panel 10 as shown in Figures 1A, 1B, and 3.

[0037] While preferred embodiments of the water intake panel and its manufacturing method have been described above, the present invention is not limited to these embodiments, and various modifications can be adopted within the spirit and scope of the invention. For example, as shown in Figure 7A, the cross-sectional shape of the wedge wire 15 may have a radius r2 of the rounded corner P1 on the upstream side, i.e., the front end, smaller than the radius r1 of the rounded corner P2 on the downstream side, i.e., the rear end. In this case, water Wa2 flowing over the top surface (base B) of the wedge wire 15 collides with the downstream side surface and is more likely to flow into the gap G, thereby increasing the amount of water intake.

[0038] In addition, in the above-mentioned embodiment, the length of the water intake panel 10 is longer than its width, but the ratio of the left-right dimensions to the front-to-back dimensions can be designed appropriately depending on the installation location, etc., and it may be, for example, square or horizontally long. [Explanation of symbols]

[0039] 10 Water intake panel 11 frames 11a, 11b side material 11c, 11d scrap wood 12 screens 13 Reinforcement bar 13a Angle 13b Base material 13c Anchor bolt 13d Concrete structure K straight line (string) K1 Difference between chord and arc 14 Rod 15 Wedge Wire C Center line of wedge wire P1 Front end (downstream side) corner r1 Radius of the front corner P2 Rear end (upstream side) corner r2 Radius of rear corner T vertex N width H Height θ Angle of forward lean rt Radius of the vertex Wa water Wa1 Part of water (taken in) Wa2 Water flowing downstream B Bottom G Gap (between adjacent wedge wires) S slot width (gap dimension) 16 Cylindrical screen

Claims

1. A water intake panel arranged in an inclined state at a water intake port for flowing water, It comprises a rectangular frame made up of left and right side members and upper and lower end members, and a screen attached to the frame, The screen is made up of a plurality of rods stretched between the upper and lower scrap materials and a plurality of wedge wires extending in the left-right direction and fixed to the rods, The wedge wire has a cross section in the shape of an inverted triangle that is long from top to bottom, and is fixed to the rod at the apex of its lower end with a forward tilt of 5 to 6 degrees. A water intake panel having a reinforcing bar fixed to the underside of at least one of the plurality of rods, the reinforcing bar extending along the underside and having a thickness approximately equal to or less than the diameter of the rod.

2. The water intake panel of claim 1 , wherein the frame, reinforcing bars and rods are curved downwardly convexly.

3. The water intake panel according to claim 1, wherein the corners at the front ends of the bases of the wedge wires are arc-shaped with a radius of 0.1 to 1.0 mm.

4. 4. The water intake panel according to claim 3, wherein the corner at the rear end of the base of the wedge wire is arc-shaped with a radius substantially the same as the radius of the corner at the front end.

5. A plurality of rods are arranged in a cylindrical shape at intervals, A wedge wire is spirally wound around the outer periphery of the rods at an angle of 5 to 6 degrees and fixed to form a cylindrical screen. Cutting the wedge wire along the gap between two adjacent rods; The cylindrical screen is opened from the cut end, and while being held in a flat or curved shape against the elastic restoring force of the wedge wire, it is attached and fixed to a rectangular frame. Manufacturing method for water intake panels.

6. 6. A method for manufacturing a water intake panel as described in claim 5, wherein after the screen is fixed to the frame, a reinforcing bar having a thickness approximately equal to or less than the diameter of the rod is fixed to the underside of at least one of the plurality of rods.

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