JPH04203120A - Iron cover of manhole and method for detecting change time thereof - Google Patents

Abstract

PURPOSE:To improve the accuracy and the workability by providing grooves in the surface of an iron cover of manhole, and filling the filling material, which is composed of pigments having different colors according to the depth, in the grooves, and detecting the abrasion condition and the change time of the iron cover with the color exposed by abrasion. CONSTITUTION:Abrasion detecting material filling grooves 6, 7 are provided in the whole circumference of the surface 5 near the center 4 of an iron cover T of a manhole and the whole circumference of the surface 5 near the peripheral edge of the iron cover T, and the epoxy group resin composed of pigments having conspicuous danger marking color different according to a depth is filled in the grooves from the bottom to the uppre part in order. Furthermore, epoxy group resin composed of the pigment having the same group color with the iron cover T is filled thereon evenly till a depth which requires change of the iron cover T. Abrasion condition and the change time of the iron cover T is detected with the color of the pigment exposed by abrasion of the iron cover T. Abrasion condition is thereby detected in the whole subrace of the iron cover T, and accurate and easy judgement is performed with only visual observation without personal equation.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical field to which the invention pertains The present invention relates to communication cables buried in roads, iron covers installed at the entrances and exits of manholes that house various buried objects, etc., and which are exposed above the road. This invention relates to a manhole iron cover that makes it easy to visually tell when it needs to be replaced due to wear due to traffic, etc., and a method for detecting when it is time to replace it.

Conventional technology FIG. 4 shows a cross-sectional view of a conventional manhole.

In the figure, the symbol l is an existing manhole installed underground, and this manhole is equipped with a conduit λ buried under the road surface for laying communication cables, a cable holder, etc. (not shown). ing. In addition, the manhole has an opening /-/ on the road as an entrance/exit.
/ is closed with iron lid 3. Most iron lids are made of cast iron, but they wear out due to heavy vehicle traffic and need to be replaced after a certain amount of wear.

Conventionally, the timing of replacing manhole iron covers installed on roads is determined by the extent to which the exclusive company emblem, mark, and design patterns displayed on the surface of the iron cover have worn out due to wear, as well as the amount of wear. There are other methods such as measuring the difference in level with the road surface by stacking measurement pieces of appropriate thickness (plastic plate pieces, vinyl plate pieces, thin plate magnets, etc.) on a worn iron lid. be.

Problems to be Solved by the Invention In the former method, personal subjectivity is largely involved in the judgment, and many individual differences occur. Other methods also have many measurement errors due to measurement technology, and regular measurements are required to quantitatively understand the wear status.
This was an extremely difficult task as it required a large amount of work.

In addition, in all conventional techniques, for wear measurement etc.
They were forced to perform dangerous work that exposed them to roadways that were frequently visited by vehicles.

The present invention has been made to solve the above-mentioned problems.

Means for Solving the Problem A groove is provided in a part of the surface of the manhole iron cover, and the need for replacement is indicated in the groove from the bottom of the groove to the part of the manhole iron cover that needs to be replaced due to wear. A filler containing a pigment of a similar color to the manhole cover is placed above the filler, and a filler containing a pigment of a similar color to that of the manhole cover is placed in the groove until it reaches the −′′ side of the manhole cover. Along with arranging and configuring the
This method detects when it is time to replace the iron lid by using the colored filling material filled in the lower part of the groove that indicates the need for replacement to be exposed due to wear.

Effect of the Invention The present invention has the structure of the iron cover as described above, so that when a manhole iron cover is installed on the road, the iron cover is worn out due to vehicle traffic, etc., and at the same time, the pigment-containing material filled in the groove is also worn out, so that it cannot be replaced. When a certain required wear thickness is reached, a noticeable color, such as red or yellow, appears.

As a result, it is possible to quickly and safely determine the wear status that requires replacement by simply visually checking the color change, regardless of individual differences, and without having to perform measurements on roads with frequent vehicle traffic. It is possible to detect when it is time to replace it due to wear.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a plan view of a manhole iron cover (hereinafter simply referred to as iron cover) of the present invention.

The structure of the iron lid of the present invention will be explained.

The symbol ≠ in Fig. 1 indicates the center of the iron lid, where the company emblem or mark of a private company is often displayed. The surface of the iron lid of j is cast with various designs, including the purpose of preventing slipping. 6 and 7 are grooves for filling material (wear detection material) installed around the entire circumference at appropriate positions near the center of the iron lid and near the edge to detect the degree of wear on the iron lid and to detect when it is time to replace the iron lid. (referred to as the filling groove).

FIG. 2 shows a sectional view of a filling groove filled with a material for detecting the degree of wear of the iron cover and detecting the timing of replacement.

The symbol r is the surface of the iron lid.

The width indicates the width of the filling groove, which should be an appropriate width of about 5-10 cm. IO indicates the depth of the filling groove, and is set to an appropriate depth of about 4 to 7 m. /l indicates an epoxy resin that has good adhesion to the iron lid T and is blended with a pigment similar in color to the iron lid T, such as black or dark brown, and is uniformly filled to a depth that requires replacement of the iron lid T.

/2 indicates an epoxy resin that has good adhesion to the iron lid T containing pigments in conspicuous danger marking colors such as red or yellow, and is applied uniformly from the bottom of the filling groove to the depth surface where the iron lid T needs to be replaced. Fill.

The surface of the iron lid due to vehicle traffic, etc.! At the same time as the epoxy resin l/ in the filling groove is worn out, when the iron lid T reaches a certain level of wear that requires replacement, an epoxy resin 12 containing a conspicuous red or yellow pigment appears, and the iron lid T wears out. It can be easily detected that it is time to replace the T.

The present invention provides a groove in the iron lid, fills pigments of different colors from the bottom to the top depending on the depth of the groove, and determines the degree of wear of the iron lid from the color of the pigment exposed at the top due to wear of the iron lid. It can be used as a detection method to detect the time for replacement.

In this example, an epoxy resin, which is a thermosetting resin, was used as the filler, but thermosetting resins such as gillyester resin and silicone resin, thermoplastic resins such as polyethylene, polypropylene, and vinyl chloride, Asphalt-based materials and even rubber materials used for adhesion to the iron lids in the filling grooves could be used as fillers.

Furthermore, it goes without saying that the number of pigments is not necessarily limited to two types; for example, a plurality of pigments may be used from the surface of the groove to the bottom of the groove so that it is easy to understand the state of wear of the manhole cover. .

Furthermore, in this example, filling grooves are provided around the entire circumference near the center of the iron lid and near the edge, but it is not necessary to provide filling grooves around the entire circumference. Filling grooves may be provided at certain locations.

Figure 3 (a) shows a plan view of the iron lid of the present invention with a company emblem and a non-slip design pattern cast on the surface of the iron lid, and (b) a cross-sectional view of the bald figure.

As described in detail, the manhole iron cover of the present invention provides the following effects.

(1) By arranging grooves for filling with epoxy resin, etc. at multiple locations on the iron lid, wear will occur on the surface of the iron lid, regardless of the installation position of the iron lid in relation to the road, the vehicle passing position, etc. It is possible to grasp the situation.

(2) Since the degree of wear of the iron lid is displayed in a conspicuous color such as red or yellow, it can be easily determined without individual differences just by visual inspection.

(3) Does not give a sense of discomfort as part of the design pattern.

[Brief explanation of the drawing]

Figure 1 is a plan view of the iron lid of the present invention, Figure 2 is a cross-sectional view of the groove filled with the wear detection material of the present invention, and Figure 3 (A) shows the company emblem and the slip on the surface of the iron lid. A plan view showing the design pattern of the stopper cast out, FIG. 4 shows a cross-sectional view, and FIG. 4 shows a cross-sectional view of a conventional manhole. T: Iron lid, ≠: Center of iron lid, j: Surface of iron lid, Otsu, 7: Groove filled with wear detection material. Patent applicant: Nippon Telegraph and Telephone Corporation Representative Patent Attorney Isao Abe T: Manhole iron cover 4, iron cover center part 5: iron cover surface portion 6.7 = groove portion filled with wear detection material

Claims (1)

[Claims] 1. A groove is provided in a part of the surface of the manhole iron cover, and the manhole iron cover wears out from the bottom of the groove.
A filling material containing a pigment of a color indicating the need for replacement is placed in the groove up to the part that requires replacement, and the manhole iron cover is placed in the groove above the filling material until it reaches the back side of the manhole iron cover. A manhole iron cover characterized by a filler containing a pigment of a similar color. 2. A groove is provided in a part of the manhole iron cover, a filler containing a pigment of a different color depending on the depth of the groove is placed in the groove, and the color of the filler is used to determine when the manhole iron cover should be replaced due to wear. A method for detecting when to replace a manhole iron cover.