JPH0816334B2 - Manhole cover for snowfall - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a manhole for a snowy area.
It relates to the lid.

[0002]

2. Description of the Related Art A manhole cover made of metal or concrete is heated by warm gases generated in the manhole to melt the frozen snow on the manhole cover to form a depression. These dents may cause unexpected slipping of tires (tires of a running vehicle) resulting in slipping and tire slipping, which could cause the steering wheel to be taken off or slip your legs while walking, resulting in a fall. It is a dangerous place. Conventionally, Japanese Patent Laid-Open No. 63-297629 discloses that the above-mentioned danger is avoided.
The manhole cover described in the official gazette and Japanese Utility Model Publication No. 2-132747 is known. The former is one in which a foam heat insulating material is integrated on the back surface of the manhole cover, and the latter is one in which an inner heat insulating plate formed by covering foam plastic with urethane resin is fixed to the back surface of the manhole cover.

[0003]

However, in the former case, the initial adiabatic effect is caused by the fact that the gas components such as ammonia, methane gas, nitrogen gas, hydrogen sulfide, etc. generated in the manhole cause a chemical change. Can't last. Since the latter covers the back surface of the manhole cover with a urethane resin, it can be expected to have a slightly longer thermal insulation effect than the former, but above all, the urethane resin has excellent weather resistance and flame retardancy. although having a, it was not particularly because it is not stable in terms of耐触against gas components described above, satisfactory in order to sustain the thermal insulation effect for a long time.

The present invention has been made in view of the conventional circumstances. The object of the present invention is particularly excellent in the effect of sustaining heat insulation.
The purpose of the present invention is to provide a manhole cover for snowfall, which is excellent in strength and manufacturability .

[0005]

In order to achieve the object of the present invention have, your in snowfall areas
Against the generated gas required for the manhole
Heat resistance, touch resistance, strength, electrical insulation, weight
The cross-sectional structure of the lid is
The product of the present invention was completed by devising it.
It That is, according to the present invention , the side plate portion is vertically provided on the outer periphery and
An outer lid made of a casting having a curved upper surface portion with a gentle slope facing the front;
The outer peripheral plate that closely contacts the inner surface of the side plate is erected and directed downward.
An inner lid made of FRP having a gently sloping curved lower surface, and
The central part formed between the outer and inner lids is thicker than the surrounding
It consists of a foamed heat insulating layer filled in the filling space.
Characterize.

[0006]

[Function] The foamed heat insulating layer has a casting outer lid and an FRP inner lid.
The central part formed between them fills the filling space that is thicker than the surroundings.
Since it is filled and formed, the phase in the manhole is
It has excellent heat insulation in the center, where the temperature is high. Casting
The outer peripheral plate of the FRP inner lid closely contacts the inner surface of the side plate of the outer lid of
Since the filling space is formed by
The foamable heat insulating layer can be reliably formed in the filling space. And outside
Since the side plate of the cast outer lid is formed around the periphery,
There is no fear of strength when mating with the base,
The upper surface of the outer lid itself is a gentle curved upward curved surface
Therefore, there is no concern about strength against load.

[0007]

EFFECT OF THE INVENTION The foaming heat insulating layer is made of a cast outer lid and FRP.
The central part formed between the inner lids is thicker than the surroundings.
Since it is filled and formed in the space,
It has excellent heat insulation in the center where the temperature is relatively high.
Has a high heat insulation effect and excellent heat insulation durability,
To prevent the occurrence of dents on the lid and prevent various accidents.
It can be blocked in advance. Side plate of outer cover made of casting
The outer peripheral plate of the FRP inner lid closely contacts the inner surface to form a filling space.
Since it is made of foam, there is no foaming
The heat layer can be reliably formed, and it is also excellent in manufacturability. So
The side plate portion of the cast outer lid is formed on the outer periphery.
Therefore, there is no fear of strength when mating with the casting die.
In addition, the outer lid itself has a gentle upward slope
Since it is a surface, there is no concern about strength against load.
Electrical insulation, light weight, thermal expansion and weather resistance.
And is excellent.

[0008]

Embodiments of the present invention will now be described with reference to the drawings. 1 and 2 show an embodiment of claim 1, and FIG. 3 shows an embodiment of claim 2. First, a description will be given based on FIGS. 1 and 2.

The cover A of the snowfall manhole includes an outer cover 1 made of casting, an inner cover 3 made of FRP, and a heat insulating layer (referred to as a foaming heat insulating layer) 2 sandwiched between the both covers 1, 3. It is composed of a three-layer structure.

The outer cover 1 made of cast metal has a side plate 1a on the outer periphery.
Vertically to and exhibit front view flat cap shape having a curved top surface portion of the upwardly gently sloping shape, to the extent that is loosely fitted to the base 101 provided around the opening edge of the manhole opening 100 that is opened in roads An accommodating port 10 for accommodating a stopper (not shown) and a lifting operation part (not shown) that are formed in a flat area and rotatably engage the base 101 at a position facing each other with the center interposed therebetween.
The notch is formed.

The inner lid 3 has strength, electrical insulation, light weight,
The FRP material (unsaturated polyester resin, glass fiber) having various properties such as low thermal expansion property, weather resistance, and resistance to generated gas and heat resistance, and the side plate portion 1 around the outer lid 1
outer peripheral plate portion 3a in a inner surface is formed in order of magnitude of the cap shaped to fit into the tight shape, downwardly gentle slope like a portion or curved lower surface portion excluding the part is placed on the die 101
Is formed .

The foam insulation layer 2 is made of a foam insulation material such as hard polyurethane foam, and the central space formed between the outer lid 1 and the inner lid 3 is thicker than the surrounding space.
a is filled with the molding material (polyurethane liquid obtained by mixing two liquids in the same amount and agitated), foaming and curing are effected, and the three members are integrally connected to each other so that they are applied between the outer lid 1 and the inner lid 3. It is made of layers, and has a substantial shape in which the portion other than the portion mounted on the base 101 is slightly thickened. This foamable heat insulating layer 2 has the property of exhibiting extremely strong adhesive force to both the outer cover 1 made of casting and the inner cover 3 made of FRP and the property of excellent heat insulation. It functions as an intermediate material that indirectly and integrally connects 1 and 3.

The cover A of the manhole for snowfall thus formed in the three-layer structure is used by forming a keyhole 11 at a desired position in a later process and attaching other necessary metal fittings. It

Therefore, the lid A of the manhole for snowfall according to the present embodiment has a strong adhesive force to the cast outer lid 1 and the FRP inner lid 3 of the hard polyurethane foam forming the foamable heat insulating layer 2 so that it can be applied to three parties. firmly constitute integrally bonded sandwich structure, receiving no thermal insulation effects to sustainability for various warm gases occurring within the manhole.

By the way, the reason why the rigid polyurethane foam is firmly adhered to the cast outer lid 1 and the FRP inner lid 3 is that the urethane resin contained functions as a universal adhesive and the composition of the both lids 1 and 3 is large. It is presumed that it is due to organic binding to the components.

Next, the manufacturing method shown in FIG. 3 will be described.
Reference numeral 4 is a clamp, and 5 is a molding material 20 for the foam insulation layer 2
It is a filling device for filling 0.

First, the casting outer lid 1 described in claim 1 and the FRP product inner lid 3 are fitted to each other to form a filling space 2a for the foamable heat insulating layer 2. In addition, a gas vent hole 3b is previously formed at a desired portion of the inner lid 3 made of an FRP product.
And the injection hole 3c of the molding material 200 is opened. Then, as shown in FIG. 3, the outer lid 1 and the inner lid 3 are clamped by clamps 4 and held upside down. A variable volume type container 5a which is made of a flexible material and stores the molding material 200 in that state
The supply hose 5b of the filling device 5 including the supply hose 5b is inserted into the injection hole 3c, and a gripping force is applied to the container 5a to pour an appropriate amount of the molding material 200 into the filling space 2a. It is manufactured by releasing the clamp 4 after a predetermined time has passed (after foaming and curing). The vent hole 3b and the injection hole 3c are FR in post-processing.
The P material is lined to fill the holes.

The feature of this embodiment is that the inner lid 3 which is an FRP product is also used as a mold for forming the heat insulating layer, and as a result, the inner lid 3 is attached and detached by the forming die (not shown) and the subsequent process.
It is possible to easily integrate the cast outer lid 1, the foamable heat insulating layer 2, and the FRP inner lid 3 without requiring any layering work (hand lay-up method, etc.).

The filling device 5 described above is not limited to the one that artificially injects the molding material, and it is of course free to adopt a mechanical injection means. In this case, it can contribute to the simplification of the manufacturing work.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of claim 1. FIG.

FIG. 2 is an enlarged vertical sectional view showing a usage state of FIG.

FIG. 3 is a longitudinal sectional view showing a state in which a molding material is filled in the embodiment of claim 2;

[Explanation of symbols]

1: Outer lid 1a made of castings Side plate 2 of outer lid 2: Thermal insulation layer 3: Inner lid 3a made of FRP Outer plate A of inner lid A: Manhole cover for snowfall

Claims (1)

[Claims] 1. A side plate is vertically provided on the outer periphery and is loosened upward.
A cast outer lid having an inclined curved upper surface and the side surface.
The outer peripheral plate that is in close contact with the inner surface of the plate is erected and gently tilted downward.
Inner lid made of FRP having a slanted curved lower surface and this outer lid
The central part formed between the inner and inner lids is thicker than the surroundings
A cover for a manhole for snowfall, which comprises a foamed heat insulating layer filled in a space .