Gratings
The grating design addresses rainwater accumulation by using protrusions with drainage guide surfaces and inclined surfaces to maintain slip resistance on both sunny and rainy days, enhancing safety.
Patent Information
- Application Number
- JP2021062126
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2021-03-31
- Publication Date
- 2025-07-28
- Estimated Expiration
- 2041-03-31
AI Technical Summary
Conventional gratings accumulate rainwater on their flat surfaces, leading to reduced friction and increased slipping risk on rainy days due to surface tension, despite having anti-slip protrusions for sunny days.
The grating design features protrusions with drainage guide surfaces and inclined surfaces to reduce surface tension, directing rainwater away from the central region and facilitating its flow off the surface, with varying protrusion sizes and shapes to enhance anti-slip properties.
The design effectively reduces rainwater accumulation and maintains high slip resistance on both sunny and rainy days by minimizing surface tension and guiding water flow, ensuring safe passage for pedestrians and vehicles.
Smart Images
Figure 0007713706000001 
Figure 0007713706000002 
Figure 0007713706000003
Abstract
Description
Technical Field
[0001] The present invention relates to gratings used, for example, for manhole covers beside roads or for floor slabs of bridges, roads, factories, etc.
Background Art
[0002] Conventionally, gratings used for manhole covers and the like have a non-slip structure on the upper surface so that pedestrians, automobiles, etc. do not slip when passing. For example, the grating disclosed in Patent Document 1 has a plurality of main members having a substantially I-shaped cross-section extending in a predetermined direction and a plurality of cross members connecting the respective main members extending in a lattice shape. On the upper surface of each main member, a plurality of protrusions having a frustum of a cone shape or a frustum of a pyramid shape project upward. Each protrusion is arranged in a staggered pattern or a lattice pattern in the longitudinal direction of the upper surface of the main member in plan view, whereby the upper surface of each main member has an uneven shape with high slip resistance.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] Incidentally, in a grating as described above, when it rains, rainwater accumulates in the flat areas of the upper surfaces of the main members, excluding the protrusions. At this time, due to surface tension, the central portion in the width direction of the main member bulges, so that it covers all or most of the areas of the protrusions provided on the upper surfaces of the main members. Then, for example, when a pedestrian or a vehicle passes over the grating, a large amount of rainwater adheres to the shoes or tires, reducing the frictional force between the upper surfaces of the main members. Even if the structure makes it difficult for pedestrians to slip and easy to pass due to the uneven shape of the upper surfaces of the main members on sunny days, there is a problem that pedestrians are likely to slip on rainy days.
[0005] The present invention has been made in view of such a point, and an object thereof is to provide a grating that allows pedestrians and vehicles to pass without slipping not only on sunny days but also on rainy days.
Means for Solving the Problems
[0006] In order to achieve the above object, the present invention is characterized in that contrivances are made to reduce the surface tension of rainwater that accumulates on the upper surfaces of the main members.
[0007] Specifically, a plurality of main members extending in a predetermined horizontal direction and a plurality of cross members connecting the main members are configured to extend in a lattice shape in a plan view, and a grating provided with a large number of anti-slip protrusions protruding upward on the upper surfaces of the main members is targeted, and the following countermeasures are taken.
[0008] That is, in the first invention, Each of the protrusions has a first protrusion arranged in a row at a predetermined interval in the longitudinal direction of the main member at the center in the width direction of the upper surface of the main member. On the Each side edge portion of the upper surface of the main member, The flat region on the upper surface of the main member excluding the protrusions becomes narrow, so that the surface tension of rainwater staying on the upper surface of the main member becomes small. a water accumulation prevention inclined surface or curved surface that gradually descends as it goes outward in the horizontal direction orthogonal to the main member is Each provided.
[0009] In the second invention, in the first invention, each of the protrusions has any one of a pyramid shape, a frustum of a pyramid shape, a hemispherical shape, and a frustum of a cone shape. Before the It is composed of one protrusion and a second protrusion arranged side by side at a predetermined interval in the longitudinal direction of the main member on at least one side portion of the upper surface of the main member, and the total occupied area of each first protrusion in the plan view of the upper surface of the main member is set to be larger than the total occupied area of each second protrusion in the plan view of the upper surface of the main member.
Effect of the Invention
[0010] In the first invention, since the flat area excluding each protrusion on the upper surface of each main member becomes narrow, the surface tension of the rainwater staying on the upper surface of each main member becomes small. Then, the rainwater staying on the upper surface of each main member easily gets over the side edge portion of each main member and flows down below the grating along the water-retaining inclined surface or curved surface, and the amount of rainwater staying on the upper surface of each main member is reduced. Therefore, for example, when a pedestrian or a vehicle passes on the grating, it is difficult for rainwater to adhere to shoes or tires, and the slip resistance between the upper surface of each main member and the uneven shape of the upper surface of each main member due to each protrusion can be increased. Thus, pedestrians and vehicles can pass without slipping their feet or tires not only on sunny days but also on rainy days.
[0011] In the second invention, when it rains on the upper surface of each main member, it becomes difficult for rainwater to accumulate in the central region in the width direction of the upper surface of each main member due to each first protrusion that widely occupies the central portion in the width direction of the main member, and the rainwater moves toward the side of the upper surface of each main member where each second protrusion is located. Therefore, it becomes easy for rainwater to flow down below the grating along the water-retaining inclined surface or curved surface from the side of the upper surface of each main member, and the amount of rainwater staying on the upper surface of each main member can be efficiently reduced.
Brief Description of the Drawings
[0012]
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
Figure 8
Figure 9
Best Mode for Carrying Out the Invention
[0013] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the following description of the preferred embodiments is merely illustrative in nature.
[0014] 《Embodiment 1 of the Invention》 FIG. 1 shows a grating 1 according to Embodiment 1 of the present invention. The grating 1 is used, for example, as a manhole cover spanning a drainage channel of a road, and includes a pair of end plates 2 in a strip shape that extend parallel to each other in the horizontal direction with a predetermined interval, and a plurality of main members 3 in a strip shape that are arranged in parallel at a predetermined interval in the longitudinal direction of the both end plates 2 and extend in the horizontal direction orthogonal to the both end plates 2 to connect the both end plates 2, and a plurality of cross members 4 that are manufactured by twisting angle steel and are arranged in parallel at a predetermined interval in the longitudinal direction of each main member 3 and extend in the horizontal direction orthogonal to each main member 3 to connect the upper side portions of each main member 3. Each main member 3 and each cross member 4 are arranged to extend in a lattice shape in a plan view.
[0015] As shown in FIG. 2, the main member 3 has a substantially I-shaped cross section with both side surfaces recessed inward, and a large number of protrusions 5 for anti-slip are provided protruding upward on the upper surface 3a of the main member 3.
[0016] The protruding portion 5 is composed of a number of first protruding portions 6 arranged in a row at equal intervals in the longitudinal direction of the main member 3 at the center in the width direction of the upper surface 3a of the main member 3, and a number of second protruding portions 7 arranged in parallel at equal intervals in the longitudinal direction of the main member 3 at each side portion of the upper surface 3a of the main member 3. As shown in FIGS. 3 and 4, each second protruding portion 7 is located between the respective first protruding portions 6 in plan view and side view.
[0017] The first protruding portion 6 has a regular hexagonal frustum shape, and its protruding height H1 is set higher than the protruding height h1 of the second protruding portion 7. In the embodiment of the present invention, the protruding height H1 of the first protruding portion 6 is set to 1 to 2.5 mm, and the maximum width dimension D1 of the first protruding portion 6 is set to 2 to 4 mm. In this way, since the upper surface 3a of the main member 3 has an uneven shape due to the first protruding portion 6 and the second protruding portion 7, it is easy for the shoes of pedestrians, the tires of automobiles, etc. to catch on the upper surface 3a of each main member 3, and the sliding resistance can be increased. In particular, by changing the protruding heights of the first protruding portion 6 and the second protruding portion 7, the uneven shape of the upper surface 3a of each main member 3 becomes more complicated compared to the case where the protruding heights are uniform, so it is easier for the shoes of pedestrians, the tires of automobiles, etc. to catch on the upper surface 3a of each main member 3, and the sliding resistance can be further increased.
[0018] The six side surfaces 6a of the first protruding portion 6 are arranged to face in a direction perpendicular to the longitudinal direction of the main member 3 in plan view.
[0019] That is, each side surface 6a is arranged to face in a direction guiding rainwater to the outside in the width direction of the main member 3, like the arrows Z1 to Z6 in FIG. 5, and is set not to be arranged in the longitudinal direction of the main member 3 like the arrows Y1 and Y2.
[0020] Of the three pairs of side surfaces 6a symmetrically located with the center line of the first protruding portion 6 as the boundary, one pair of side surfaces 6a is arranged to face in a horizontal direction perpendicular to the longitudinal direction of the main member 3 in plan view, and constitutes the drainage guide surface 6A of the present invention.
[0021] As shown in FIG. 6, the ratio P1 of the dimension D1 of the first protrusion 6 in the width direction of the main member 3 to the dimension D2 of the main member 3 in the width direction on the upper surface 3a of the main member 3 is set to be 0.25 or more.
[0022] The second protrusion 7 has a regular triangular pyramid shape. As shown in FIG. 3, the second protrusions 7 arranged on one side portion of the upper surface 3a of the main member 3 and the second protrusions 7 arranged on the other side portion are symmetrically shaped about the central portion in the width direction of the main member 3.
[0023] The three side surfaces 7a of the second protrusion 7 are arranged in a direction guiding rainwater to the outside in the width direction of the main member 3 as shown by the arrows z1 to z3 in FIG. 5, and are set so as not to be arranged in the longitudinal direction of the main member 3 such as the arrows Y1 and Y2.
[0024] One side surface 7a of the second protrusion 7 is arranged in a horizontal direction orthogonal to the longitudinal direction of the main member 3 in a plan view, and constitutes the drainage guide surface 7A of the present invention.
[0025] As shown in FIG. 5, the total occupied area F1 of each first protrusion 6 in the plan view of the upper surface 3a of the main member 3 is set to be larger than the total occupied area f1 of each second protrusion 7 in the plan view of the upper surface 3a of the main member 3 as shown in FIG. 4.
[0026] On each side edge portion of the upper surface of the main member 3, a water retention prevention inclined surface 8 that gradually descends as it goes outward in the horizontal direction orthogonal to the main member 3 is provided respectively.
[0027] As shown in Fig. 6, the inclination angle α of the inclined surface 8 for preventing water stagnation is set to 30 to 80 degrees. Since the inclined surface 8 for preventing water stagnation has a shape that linearly extends obliquely downward, when the inclined surface 8 for preventing water stagnation is provided on the main member 3, a corner portion 8a is formed at the continuous portion between the inclined surface 8 for preventing water stagnation and the upper surface 3a of the main member 3. Therefore, since the corner portion 8a is likely to catch on the shoes of pedestrians during passage, it can be made into the grating 1 that is easy for pedestrians and the like to pass even in rainy weather. Also, since the inclined surface 8 for preventing water stagnation has a shape that linearly extends obliquely downward, it can be formed on the main member 3 by simple processing, and there is also the merit that the manufacturing cost can be kept low.
[0028] The inclined surface 8 for preventing water stagnation located on one side in the width direction of the main member 3 faces the same direction in plan view as the drainage guide surfaces 6A and 7A located on one side in the width direction of the main member 3, and the inclined surface 8 for preventing water stagnation located on the other side in the width direction of the main member 3 faces the same direction in plan view as the drainage guide surfaces 6A and 7A located on the other side in the width direction of the main member 3.
[0029] As shown in Fig. 6, the ratio P2 of the dimension D4 in the width direction of the main member 3 in each inclined surface 8 for preventing water stagnation to the width dimension D3 of the main member 3 is set to 0.1 to 0.3. In the embodiment of the present invention, the width dimension D3 of the main member 3 is set to 7 to 10 mm.
[0030] Next, the state around each main member 3 of the grating 1 in rainy weather will be described in detail.
[0031] As shown in FIGS. 5 and 6, rainwater pouring onto the first protrusions 6 and the second protrusions 7 of each main member 3 during rainy weather flows down along the respective side surfaces 6a of the first protrusions 6 and the respective side surfaces 7a of the second protrusions 7 and reaches the flat region on the upper surface of the main member 3 and accumulates water (see the water accumulation portion 9 in FIG. 6). At this time, since each main member 3 of the present invention is provided with an inclined surface 8 for preventing water accumulation, the flat region excluding the first protrusions 6 and the second protrusions 7 on the upper surface 3a of each main member 3 becomes narrower, and the surface tension of the rainwater accumulating on the upper surface 3a of each main member 3 becomes smaller. Then, the rainwater accumulating on the upper surface 3a of each main member 3 easily crosses the side edge portion of each main member 3 and flows down along the inclined surface 8 for preventing water accumulation below the grating 1, and the amount of rainwater accumulating on the upper surface 3a of each main member 3 is reduced. Therefore, for example, when a pedestrian or a vehicle passes on the grating 1, it becomes difficult for rainwater to adhere to shoes or tires, and the uneven shape of the upper surface 3a of each main member 3 due to each first protrusion 6 and each second protrusion 7 can increase the sliding resistance between the upper surface 3a of each main member 3, so that pedestrians and vehicles can pass without slipping their feet or tires not only in sunny weather but also in rainy weather.
[0032] Also, since the total occupied area F1 of each first protrusion 6 in the plan view of the upper surface 3a of the main member 3 is set to be larger than the total occupied area f1 of each second protrusion 7 in the plan view of the upper surface 3a of the main member 3, it becomes difficult for rainwater to accumulate in the central region in the width direction of the upper surface 3a of each main member 3 by each first protrusion 6, and the rainwater moves to the side of the upper surface 3a of each main member 3 where each second protrusion 7 is located. Therefore, rainwater easily flows down from the side of the upper surface 3a of each main member 3 along the inclined surface 8 for preventing water accumulation below the grating 1, and the amount of rainwater accumulating on the upper surface 3a of each main member 3 can be efficiently reduced.
[0033] Also, as shown in FIG. 5, since each side surface 6a of the first protrusion 6 and each side surface 7a of the second protrusion 7 face in a direction intersecting the longitudinal direction of the main member 3 in plan view, each side surface 6a, 7a is configured to move the rainwater laterally on the upper surface 3a of the main member 3. Therefore, the rainwater can more easily flow down from the side of the upper surface 3a of each main member 3 along the water-stagnation prevention inclined surface 8 to below the grating 1.
[0034] In particular, since the first protrusion 6 and the second protrusion 7 are provided with drainage guide surfaces 6A, 7A that face in the same direction as the water-stagnation prevention inclined surface 8 in plan view, when the rainwater pouring onto each first protrusion 6 and each second protrusion 7 flows along the drainage guide surfaces 6A, 7A, the rainwater will flow down along the water-stagnation prevention inclined surface 8 as it is and reach below the grating 1. Therefore, the rainwater stagnating on the upper surface 3a of each main member 3 can be efficiently removed.
[0035] 《Embodiment 2 of the Invention》 FIG. 7 shows the grating 1 according to Embodiment 2 of the present invention. In this Embodiment 2, since it is the same as Embodiment 1 except that both side surfaces of the main member 3 are flat and have a substantially strip-shaped cross-section, the same reference numerals are given to the same parts as in Embodiment 1, and detailed descriptions thereof are omitted. From the above, according to Embodiment 2 of the present invention, even if the shapes of both side surfaces of the main member 3 are flat, the same effects as in Embodiment 1 can be obtained.
[0036] 《Embodiment 3 of the Invention》 FIG. 8 shows the grating 1 according to Embodiment 3 of the present invention. In this Embodiment 3, since it is the same as Embodiment 1 except that the structure of the main member 3 is different from that in Embodiment 1, the same reference numerals are given to the same parts as in Embodiment 1, and only the different parts will be described.
[0037] The protrusion 5 on the upper surface 3a of the main member 3 in Embodiment 3 has a frustum of a cone shape and is arranged in a staggered pattern alternately on one side and the other side in the width direction of the main member 3 along the longitudinal direction of the main member 3.
[0038] As described above, according to Embodiment 3 of the present invention, even if the outer shape of the protrusion 5 on the upper surface 3a of the main member 3 is trapezoidal frustum-shaped, the same effects as those of Embodiment 1 can be obtained.
[0039] 《Embodiment 4 of the Invention》 FIG. 9 shows the grating 1 of Embodiment 4 of the present invention. In this Embodiment 4, since it is the same as Embodiment 3 except that the structure of each protrusion 5 is different from that of Embodiment 1, the same reference numerals are given to the same parts as those in Embodiment 3, and only the different parts will be described below.
[0040] The protrusions 5 on the upper surface 3a of the main member 3 in Embodiment 3 are hemispherical in shape, and are arranged in a staggered pattern alternately on one side and the other side in the width direction of the main member 3 along the longitudinal direction of the main member 3.
[0041] As described above, according to Embodiment 4 of the present invention, even if the outer shape of the protrusion 5 on the upper surface 3a of the main member 3 is hemispherical in shape, the same effects as those of Embodiment 3 can be obtained.
[0042] In addition, in Embodiments 1 to 4 of the present invention, the water-retaining prevention inclined surfaces 8 are provided on both side edges of the upper surface 3a of the main member 3, but a structure in which the water-retaining prevention inclined surface 8 is provided only on one side edge of the upper surface 3a of the main member 3 may also be used.
[0043] Also, in Embodiments 1 and 2 of the present invention, the protruding height H1 of the first protrusion 6 is set higher than the protruding height h1 of the second protrusion 7, but it is not limited to this, and they may be set to the same height or a lower height.
[0044] Also, in Embodiments 1 to 4 of the present invention, in order to improve the drainage property of the upper surface 3a of the main member 3, the water-retaining prevention inclined surfaces 8 extending linearly obliquely downward are formed on both side edges of the upper surface 3a of the main member 3, but it is not limited to this, and curved surfaces for preventing water retention that extend while curving obliquely downward may be formed on both side edges of the upper surface 3a of the main member 3 to improve the drainage property of the upper surface 3a of the main member 3.
[0045] In addition, in the first and second embodiments of the present invention, the first protrusion 6 has a regular hexagonal pyramid shape and the second protrusion 7 has a regular triangular pyramid shape, but this is not limited thereto, and the shapes may be pyramid or truncated pyramid shapes having a different number of corners, or may be circular truncated cone or cone shapes.
[0046] Furthermore, although the main member 3 in the third and fourth embodiments of the present invention has a substantially I-shaped cross section, it may have a substantially band-like cross section as in the second embodiment.
[0047] In addition, in the first to fourth embodiments of the present invention, the protrusions 5 are provided at equal intervals in the longitudinal direction of the main component 3, but this is not limiting, and it is sufficient that they are provided at predetermined intervals in the longitudinal direction of the main component 3. [Industrial Applicability]
[0048] The present invention is suitable for gratings used, for example, in roadside groove covers or decks of bridges, roads, factories, etc. [Explanation of symbols]
[0049] 1 Grating 3 Main parts 3a Top surface of main part 4 Lateral member 5. Protrusion 6 First protrusion 6A Drainage guide surface 6a Side of the first protrusion 7 Second protrusion 7A Drainage guide surface 7a Side of second protrusion 8. Slopes to prevent water retention
Claims
1. A grating configured such that a plurality of main members extending in a predetermined horizontal direction and a plurality of horizontal members connecting the respective main members extend in a lattice pattern in plan view, and a large number of anti-slip protrusions protruding upward are provided on the upper surface of each of the main members, each of the protrusions having a first protrusion arranged in a row at a predetermined interval in the longitudinal direction of the main member at the center in the width direction of the upper surface of the main member, on each side edge portion of the upper surface of the main member, an inclined surface or a curved surface for preventing water stagnation that gradually positions downward as it goes outward in the horizontal direction orthogonal to the main member is provided so that a flat region excluding the respective protrusions on the upper surface of the main member becomes narrower and the surface tension of rainwater stagnating on the upper surface of the main member becomes smaller, the grating, wherein the first protrusion has any one of a pyramid shape, a truncated pyramid shape, a hemispherical shape, and a truncated cone shape.
2. The grating according to claim 1, each of the protrusions being composed of the first protrusion and a second protrusion arranged in a row at a predetermined interval in the longitudinal direction of the main member on at least one side portion of the upper surface of the main member, the grating, wherein the total occupied area of each first protrusion in plan view of the upper surface of the main member is set to be wider than the total occupied area of each second protrusion in plan view of the upper surface of the main member.
Citation Information
Patent Citations
JP1978062074U
JP1987044943U
JP1988151505U
JP1989141888U
Metal grating
JP1995217065A