JPH053557Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to an improvement of a manhole cover structure.

(Prior Art) A conventional manhole cover generally includes a stepped iron receiving frame disposed at the upper part of the side wall of the manhole, and an iron cover fitted and placed on the receiving frame.

(Problems to be solved by the invention) By the way, regarding the above manhole cover structure,
Due to dimensional errors in manufacturing, it is unavoidable that a gap will occur between the outer circumferential surface of the lid and the inner circumferential surface of the receiving frame, and if there is a gap between the lid and the receiving frame, dirt and
Dirt, sand, water, etc. accumulate and the lid becomes stuck to the receiving frame. In particular, when water accumulates in the gap, iron rust occurs in this area, causing the lid and the receiving frame to stick to each other, making it extremely difficult to open the lid.

On the other hand, when a manhole cover is provided on a roadway, when a car runs over the manhole cover, the rotational moment of the wheels causes the cover to rattle, generating noise and damaging the cover and the receiving frame.

The present invention solves the above problems, and aims to provide a manhole cover structure that prevents the manhole cover from sticking and wobbling.

(Means for solving the problem) For this reason, the technical means of the present invention is to create a gap between the outer circumferential surface of the manhole cover and the inner circumferential surface of the receiving frame of the cover that almost matches the gap between both circumferential surfaces. It is characterized by being equipped with an annular glass fiber-reinforced plastic packing having a cross-sectional shape.

The ring shape of the gasket is formed according to the shape of the lid and the receiving frame, and includes not only a circular shape but also a square shape. The material of the packing is plastic, preferably fiber-reinforced plastic, which has excellent mechanical strength.
The material of the lid and the receiving frame is not particularly limited, and may be iron or fiber-reinforced plastic.

(Function) In the present invention, the gasket interposed between the lid and the receiving frame has a thickness that corresponds to the gap between the lid and the receiving frame, and is placed between the outer peripheral surface of the lid and the inner peripheral surface of the receiving frame. This allows the gap between the two to be eliminated. Therefore, dirt, dirt, sand, water, etc. do not accumulate between the lid and the receiving frame, and it is possible to prevent the lid and the receiving frame from sticking together.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings. In FIG. At the top, a circular receiving frame 3 having a stepped portion on the upper surface is arranged. A circular lid 4 having a slightly smaller diameter than the stepped portion is placed on the stepped portion of the receiving frame 3. Here, the lid 4 and the receiving frame 3 are made of cast iron or glass fiber reinforced plastic. Lid 4
Between the outer peripheral surface of the receiving frame 3 and the inner peripheral surface of the receiving frame 3, a ring-shaped glass fiber-reinforced plastic packing 5 having a cross-sectional shape that almost matches the gap between the two (4, 3) is installed ( (see FIG. 2), there is no gap between the lid 4 and the receiving frame 3.

In this way, the gasket 5 is placed between the lid 4 and the receiving frame 3.
If the structure is such that the gap between the two 4 and 3 is eliminated by interposing the lid 4 and the receiving frame 3, there will be no room for dirt, soil, sand, water, etc. are not stuck together. In addition, even if a car runs on the lid 4, the lid 4
Since the movement is regulated by the seal 5, no rattling occurs. Therefore, noise generation is prevented and the durability of the lid 4 and the receiving frame 3 is improved.

FIG. 3 shows another embodiment of the present invention, and its characteristics are that the inner peripheral surface of the stepped portion of the receiving frame 3 is expanded into a tapered shape, and the lid 4 is expanded in a tapered shape.
The outer peripheral surface of the support frame 3 is formed so as to face the inner peripheral surface of the receiving frame 3, and between the lid 4 and the support frame 3, there is provided an annular ring having a cross-sectional shape that substantially matches the gap between the lid 4 and the support frame 3. This is because the gasket 5 made of glass fiber reinforced resin is attached. Even with this configuration, it is possible to prevent the lid 4 of the manhole 1 from sticking and wobbling, as in the previous embodiment.

As shown in FIG. 4, if the thickness t of the lid 4 and the depth d of the receiving frame 3 are different from each other due to variations in manufacturing dimensions, the gasket 5
The height of the portion of the top surface that contacts the lid 4 and the receiving frame 3 is set to be the same as the top surface of the lid 4 and the receiving frame 3, respectively, and the top surface of the gasket 5 is formed into a convex shape. Therefore, the difference in level between the top surface of the lid 4 and the top surface of the receiving frame 3 can be eliminated as much as possible.

(Effects of the invention) As described above, according to the invention, by attaching an annular glass fiber reinforced plastic packing between the lid and the receiving frame, dirt, soil, sand, etc. can be removed between the lid and the receiving frame. Since water and the like do not accumulate, it is possible to prevent the lid and the receiving frame from sticking to each other as in the conventional case. Furthermore, even when a car runs on the manhole cover, the cover does not wobble due to the rotational moment of the wheels, and furthermore, the lid does not wobble at all because its movement is regulated by the gasket. Since glass fiber-reinforced plastic with excellent mechanical strength is used for the packing, the packing functions as a cushioning material and can also improve abrasion resistance, so the durability of the lid and receiving frame is improved compared to conventional ones. Furthermore, since the receiving frame is a plastic product, it can be easily formed into any ring shape depending on the lid and the receiving frame, and it is lightweight and can be mass-produced at low cost.

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view showing one embodiment of the present invention, Fig. 2 is a perspective view showing the packing shown in Fig. 1, Fig. 3 is a longitudinal cross-sectional view showing another embodiment of the present invention, Fig. 4 FIG. 3 is an enlarged vertical cross-sectional view showing a modification of the packing shape shown in FIG. 2; 1... Manhole, 3... Receiving frame, 4... Lid,
5... Patsukin.

Claims (1)

[Scope of utility model registration request] A ring-shaped glass fiber-reinforced plastic packing having a cross-sectional shape that substantially matches the distance between the two circumferential surfaces is attached between the outer circumferential surface of the manhole cover and the inner circumference of the receiving frame of the cover. Manhole cover structure.