JP5685730B2 - The lid body of the lid for underground structures - Google Patents

Description

  The present invention relates to a lid body of a lid for an underground structure that is exposed in the ground and is installed in the ground.

  In addition, the term “underground structure lid” as used in the present specification means a manhole cover, a large iron cover, a sewage culm lid, an electric power / Openable and closable joint gutter lids, power transmission iron lids, power distribution iron lids, buried conduits under the road surface in waterworks and gas pipes, and their associated devices, which protect underground facilities equipment and underground cables, etc. in communications A fire hydrant lid, a water control valve lid, a gate valve lid, an air valve lid, a gas pipe lid, a water meter lid, etc., that function as an open / close door.

  Conventionally, lids for underground structures have been filled with colored resin, such as epoxy resin, in the recesses of the lid body made of cast iron, improving the landscape on the road as a colorful design, or being buried underground The convenience and visibility of maintenance are improved by displaying the facilities and devices that have been used.

  As such a lid for underground structures, there is a color iron lid for underground structures described in Patent Document 1. In this case, a pattern is formed on the surface of the lid body by convex portions and concave portions, and the concave portions are filled with a colored resin.

  However, if the colored resin is filled in the concave portion of the lid body made of cast iron in this way, a gap may be generated between the lid body and the colored resin from the beginning due to shrinkage when the colored resin solidifies, and there is no gap. Even in such a case, there is a problem that, when the internal stress remains, peeling occurs due to repeated load due to passing of the vehicle or the like, and the scenery and visibility are deteriorated.

  Moreover, since it is necessary to replace | cover the lid | cover main body itself in order to recover scenery property and visibility, there existed a problem that the cost burden of a maintenance manager also became large.

  In order to solve such a problem, there is a cover for an underground structure in which a resin base plate is fitted in a recess of a cast iron frame and is detachably fixed (Patent Document 2).

However, in the lid for underground structures of Patent Document 2, when the traffic volume of a large vehicle is large, a horizontal force is applied to the resin base plate to cause a lateral shift, and the lower surface of the resin base plate is worn. There was a risk of rattling of the resin base plate.

JP 2005-299154 A JP 2010-84407 A

  The problem to be solved by the present invention is to prevent the resin plate member from rattling for a long time in the lid body of the underground structure lid in which the resin plate member is mounted in the recess of the cast iron member. Is to make it.

The present invention relates to a lid body of a cover for an underground structure that is exposed in the ground with the surface exposed, and the lid body is made of a cast iron lid having a recess on the surface side and a resin made removable to the recess. The resin plate, the resin plate is interposed between a bottom surface of the resin plate and the bottom surface of the recess, and a resin sheet separate from the resin plate is interposed between the resin plate and the recess by mechanical means. It is characterized by being mounted and fixed.

  Thus, by interposing the resin sheet on the contact surface between the resin plate and the concave portion of the cast iron lid portion, the contact surface between the resin plate and the concave portion is modified, and the resin due to the lateral displacement of the resin plate. Wear on the bottom surface of the plate is suppressed, and rattling can be prevented for a long time.

  If the material of the resin sheet interposed on the contact surface is too hard, the lower surface of the resin plate tends to be worn, and if too soft, the fixing of the resin plate tends to become unstable. That is, the material of the resin sheet is preferably selected to have the same degree of hardness in relation to the material of the resin plate. Specifically, the material of the resin sheet is the same material as the resin plate. It is preferable that

  In addition, the resin sheet preferably has a shape that covers the entire bottom surface of the recess, from the viewpoint of more reliably suppressing wear of the bottom surface of the resin plate due to contact between the bottom surface of the resin plate and the bottom surface of the recess of the cast iron lid. .

  Furthermore, in the present invention, it is preferable to arrange the packing so as to surround at least a part of the side surface of the resin plate over the entire circumference. By arranging the packing in this way, lateral displacement of the resin plate is suppressed, and intrusion of earth and sand into the contact surface between the resin plate and the concave portion of the cast iron lid portion is suppressed, and abrasion caused by the resin sheet The reduction effect can be further enhanced.

  ADVANTAGE OF THE INVENTION According to this invention, generation | occurrence | production of the rattling of the resin-made plate with which the recessed part of the lid part made from cast iron was attached can be prevented over a long period of time. Therefore, the landscape and visibility of the resin plate can be maintained for a long period of time, the replacement cycle of the resin plate fixed to the lid body of the underground structure lid can be extended, and the cast iron lid part Life can be extended.

An example of the lid | cover for underground structures to which the lid | cover main body of this invention is applied is shown, (a) is a top view, (b) is AA sectional drawing of (a). It is a disassembled perspective view which shows the structure of the cover main body of the cover for underground structures shown in FIG. It is a reverse view of the resin-made plates which comprise the cover main body of the cover for underground structures shown in FIG. It is sectional drawing of the principal part which shows the mounting state of an IC tag. It is an expanded sectional view of the principal part of the lid body by the BB section of Drawing 1 (a). The result of the wheel load test of the product of the present invention and the comparative product is shown.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows an example of an underground structure lid to which the lid body of the present invention is applied, wherein (a) is a plan view and (b) is an AA cross-sectional view of (a).

  The underground structure lid 100 shown in FIG. 1 is a gate valve lid, and includes a lid body 200 and a receiving frame 500 that supports the lid body 200 via a hinge mechanism 400 so as to be opened and closed. The underground structure lid 100 is installed in the ground such that the surface of the lid body 200 is exposed to the ground surface.

  FIG. 2 is an exploded perspective view showing the configuration of the lid body 200. The lid body 200 includes a cast iron lid portion 210 having a recess 211 on the surface side thereof, and a base plate 220 as a resin plate that can be mounted in the recess 211 of the cast iron lid portion 210.

  The base plate 220 is made of a thermoplastic resin such as polycarbonate having wear resistance, impact resistance and compressive strength, and is formed by injection molding or the like, and a plurality of convex portions 221 are provided on the surface thereof as slip prevention and design. It has been. Various information display plates 230 for displaying information such as the types of valve plugs, the diameter, the type of fluid, the flow direction, and the management number are attached to the surface of the base plate 220 as an information transmission medium. Further, a hexagonal nut 290 is insert-molded in advance on the back surface side of the base plate 220 (see FIG. 5), and an IC tag 240 that can read and write position information and maintenance information wirelessly is used as an information storage medium. It is attached.

  Specifically, the IC tag 240 is inserted into a cylindrical portion 222 formed by circular ribs on the back surface of the base plate 220 shown in FIG. 3, and a fixing member made of an elastic resin foam shown in FIG. By fitting 250, as shown in FIG. 4, it is placed at a predetermined height position in the cylindrical portion 222 in a state of being placed on the upper surface of the fixing member 250. Then, an IC tag position display mark 223 shown in FIG. 2 is provided on the surface of the base plate 220 at a position corresponding to the mounting position of the IC tag 240 so that the mounting position of the IC tag 240 can be seen from the surface side of the base plate 220. ing.

In this embodiment, 12 hexagonal nuts 290 made of SUS304 and M6 are insert-molded on the back side of the base plate 220. The installation location of the hexagon nut 290 in this embodiment is as shown in FIG. 3, but the larger the number used, the more firmly the base plate 220 and the cast iron lid portion 210 can be fixed, while the number of manufacturing steps increases. Therefore, the number of hexagon nuts 290 to be installed can be appropriately set depending on the shape and size of the lid body.

  The base plate 220 having the above configuration is fitted into the recess 211 of the cast iron lid portion 210 and fixed integrally. FIG. 5 is a diagram showing the fixed state, and is an enlarged cross-sectional view of the main part of the lid main body 200 along the BB cross section of FIG.

  When the base plate 220 is fitted and fixed in the concave portion 211 of the cast iron lid portion 210, a resin sheet 260 is interposed between the bottom surface of the base plate 220 in which the hexagon nut 290 is insert-molded in advance and the bottom surface of the concave portion 211, and The packing 270 is disposed so as to surround the entire periphery of the lower surface peripheral portion and side surface lower end portion of the base plate 220. Then, a high-tensile hexagon bolt 280 is attached to the pace plate 220 from the back surface side of the cast iron lid portion 210 via a plain washer 300, and the base plate 220 and the cast iron lid portion 210 are fastened. As a result, the base plate 220 is attached and fixed to the concave portion 211 of the cast iron lid portion 210. If the high-tension hexagon bolt 280 is removed, the base plate 220 can be removed from the cast iron lid portion 210, and only the base plate 220 can be replaced. The means for mounting and fixing the base plate 220 to the recess 211 of the cast iron lid part 210 is not limited to the high-tensile hexagon bolt 280 and the insert-molded hexagon nut 290 as long as it is a mechanical means. May be used.

  As shown in FIG. 2, the resin sheet 260 interposed between the lower surface of the base plate 220 and the bottom surface of the recess 211 has a shape that covers the entire bottom surface of the recess 211. That is, the planar shape of the resin sheet 260 is the same as the planar shape of the bottom surface of the recess 211. The material of the resin sheet 260 is made of a thermoplastic resin such as polycarbonate as in the case of the base plate 220. In the present embodiment, the resin sheet 260 is made of the same material (polycarbonate) as the base plate 220. The material is not limited to polycarbonate, but engineer plastic is preferred. The thickness of the resin sheet 260 is about 0.1 to 1.0 mm. Such a resin sheet 260 can be obtained by punching and molding an original plate with a Thomson mold.

  As shown in FIG. 2, the packing 270 has a shape that surrounds the lower peripheral edge and side lower end of the base plate 220, and when used, as shown in FIG. 5, the entire circumference of the lower peripheral edge and side lower end of the base plate 220 is used. It is arranged so that it surrounds. In order to achieve such an arrangement, it is easy to preliminarily attach the packing 270 to the base plate 220 so as to surround the entire periphery of the lower surface peripheral edge portion and the side surface lower end portion. In addition, the packing 270 may be bonded so as to surround the peripheral edge of the upper surface of the resin sheet 260. The material of the packing 270 is not limited as long as it has water-stopping and weather resistance, and is made of, for example, chloroprene rubber. The packing 270 can be obtained by molding by injection molding.

  Here, on the outer periphery of the base plate 220, as shown in FIG. 5, a projecting portion 224 having a quadrilateral circular sectional shape that is slightly larger than the inner diameter of the concave portion 211 of the cast iron lid portion 210 is formed over the entire circumference. Has been. The protrusions 224 are surely brought into contact with the side surfaces of the concave portion 211 of the cast iron lid portion 210 so that the base plate 220 is securely fitted into the concave portion 211. The vertical cross-sectional shape of the protrusion 224 is a curved surface such as a quadrant or a semicircle so that when the base plate 220 is pushed in, the base plate 220 is smoothly fitted while being in contact with the side surface of the recess 211 of the cast iron lid 210. It is preferable. In addition, the position where the protrusion 224 is provided is preferably the upper side of the side surface of the base plate 220 in order to prevent inflow of rainwater and earth and sand.

  As described above, in the lid main body 200 of the present invention, the contact surface between the base plate 220 and the recess 210 is modified by interposing the resin sheet 260 on the contact surface between the base plate 220 and the recess 210 of the cast iron lid portion 210. The wear of the lower surface of the base plate 220 due to the lateral displacement of the base plate 220 is suppressed. Therefore, the occurrence of rattling of the base plate 220 can be prevented for a long time.

  Moreover, in this embodiment, since the packing 270 is arrange | positioned so that the perimeter of the lower surface peripheral part of the baseplate 220 and a side surface lower end part may be enclosed, while the horizontal shift of the baseplate 220 is suppressed, the baseplate 220 and a cast iron lid | cover are suppressed. Infiltration of earth and sand into the contact surface of the portion 210 with the concave portion 211 is suppressed, and the wear reduction effect by the resin sheet 260 can be further enhanced. In the present embodiment, the packing 270 is disposed so as to surround the entire circumference of both the lower surface peripheral edge portion and the side surface lower end portion of the base plate 220. However, if the packing 270 is disposed so as to surround at least a part of the side surface over the entire circumference, The effect of suppressing the lateral displacement of the base plate and the intrusion of earth and sand can be obtained.

  In the above embodiment, the base plate 220 is mounted as the resin plate in the concave portion 211 of the cast iron lid portion 210. However, the resin plate is not limited to the base plate 220, and for example, the information display shown in FIG. A plate member 231 indicating the type of valve plugs or a plate member 232 indicating a control number, which is one of the plates 230, may be mounted as a resin plate in the recess of the cast iron lid. Also in this case, wear of the lower surface of the resin plate can be suppressed by interposing the resin sheet on the contact surface between the resin plate and the concave portion of the cast iron lid portion. The “resin plate” as used in the present invention is a concept including a plate body portion provided with an accessory such as a fixing leg as in the plate member 232 described above.

  Moreover, in this embodiment, although this invention was applied to the gate valve cover, it cannot be overemphasized that it is applicable also to other underground structure covers, such as a manhole cover and a fire hydrant cover.

  2 using the resin sheet 260 (the packing 270 is not used) and the lid body of the present invention (the product of the present invention) and the comparative example in which the resin sheet 260 is not used in FIG. 2 (the packing 270 is not used). The lid body (comparative product) was subjected to a wheel load running test. In the wheel load running test, a double tire used in a large vehicle was used, a vertical load was applied to the tire, and the vehicle was repeatedly run on the laid lid body, and the amount of wear on the lower surface of the base plate 220 was measured. Specifically, the vertical load applied to the tire was set to 100 kN, and the test was performed while spraying water in a state where earth and sand were laid on the surface and the periphery of the lid main body.

  The result is shown in FIG. As shown in the figure, in the comparative product, 0.07 mm of wear was generated after running 30,000 times and 0.08 mm of wear was generated after running 60,000 times, whereas lateral displacement was observed in the product of the present invention, but 60,000 times. No abrasion was observed even during running, and the effect of reducing wear by the resin sheet was confirmed.

DESCRIPTION OF SYMBOLS 100 Cover for underground structures 200 Cover body 210 Cast iron cover 211 Recess 220 Base plate (resin plate)
221 Convex part 222 Concave part 223 IC tag position display mark 224 Protrusion part 230 Information display plate 231 Plate member indicating the type of valve plugs 232 Plate member indicating control number 240 IC tag 250 Fixing member 260 Resin sheet 270 Packing 280 High tension Hexagon bolt 290 Hexagon nut 300 Plain washer 400 Hinge mechanism 500 Receiving frame

Claims (4)

In the lid body of the cover for underground structures that are exposed in the ground with the surface exposed,
The lid body includes a cast iron lid portion having a recess on the surface side, and a resin plate detachable from the recess,
The resin plate is mounted and fixed in the recess by mechanical means with a resin sheet separate from the resin plate interposed between the lower surface of the resin plate and the bottom surface of the recess. The lid body of the lid for underground structures.   The lid body of the lid for an underground structure according to claim 1, wherein the resin plate and the resin sheet are made of the same material.   The lid body of the lid for an underground structure according to claim 1 or 2, wherein the resin sheet has a shape covering the entire bottom surface of the recess.   The lid body of the lid for an underground structure according to any one of claims 1 to 3, wherein a packing is disposed so as to surround at least a part of the side surface of the resin plate over the entire circumference.

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