JPH10183741A - Reinforcing structure of lid main body in pit lid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively increase flexural rigidity of a pit lid in which a lid main body supported in a peripheral fringe part of an opening formed on an installation face on which a person can walk in such a manner that the opening is closed is constituted by an upper wall, a lower wall, and a plurality of connection walls which are provided in parallel across an interval between the upper wall and the lower wall mutually and connect sections between them integrally without changing the thickness of the pit lid. SOLUTION: A reinforcing structure of a lid main body Tm is provided with a plurality of first engaging ditches 3a which are provided in parallel across an interval mutually on a lower face of an upper wall 3 between adjacent connection walls 5 and 5 of the lid main body Tm. It is provided with a plurality of second engaging ditches 4a which are provided in parallel on a top face of a lower wall 4 by corresponding to the first engaging ditches 3a, respectively, and at least one reinforcing sash bar L formed like a belt plate so that both upper and lower fringe parts can be inserted and fixed into each first engaging ditch 3a and each second engaging ditch 4a which corresponds to each first engaging ditch 3a, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for reinforcing a lid body in a pit lid capable of opening and closing an opening of a pit or the like recessed on a walkable installation surface (for example, an indoor floor or an outdoor ground). .

[0002]

2. Description of the Related Art Open pits for wiring cables or water supply / drainage provided on floors in rooms and various tanks buried in outdoor treatment facilities and the like are covered with their open upper surfaces (namely, openings in installation surfaces). A pit lid is provided which is substantially flush with the installation surface.

[0003] The lid body of such a pit lid needs to have particularly sufficient bending rigidity so that it can withstand the weight of a pedestrian or the like. And in order to increase the bending rigidity of the pit lid in this way, it is customary, for example, to thicken the lid plate as a whole or to attach a reinforcing material to the back surface of the lid. As the lid weight increases,
There are also problems such as the lid itself becoming unnecessarily thick or unnecessary projections projecting toward the pits on the back surface of the lid.

[0004]

In order to solve the above problem, in recent years, a pit lid having a hollow closed-section structure by extrusion molding or drawing molding has been proposed.
Even in this case, as means for further increasing the bending stiffness, a sufficient number of lids (those having different thicknesses and cross-sectional shapes) corresponding to the assumed loads are assumed in a sufficient number, assuming several large and small load resistances in advance. It had to be prepared, and there was a problem that the cost increased as a whole.

The present invention has been made in view of such circumstances, and has been made to solve the above-described problems of the conventional one at a time, and to increase the bending rigidity of the pit lid without changing the thickness thereof. It is another object of the present invention to provide a structure for reinforcing a lid body in a pit lid.

[0006]

In order to achieve the above object, according to the first aspect of the present invention, a lid body supported on a peripheral portion of an opening formed on a walkable installation surface is closed by an upper wall. And a lower wall having an upper surface opposed to the lower surface of the upper wall with a gap, and a plurality of connecting walls which are arranged side by side with an interval between the upper wall and the lower wall and integrally connected therebetween. In the reinforcing structure of the lid main body in the pit lid configured as above, a plurality of first engagement grooves which are juxtaposed at intervals on the lower surface of the upper wall between the adjacent coupling walls, A plurality of second parallelly disposed on the upper surface of the lower wall corresponding to the mating grooves, respectively.
At least one reinforcement formed in a strip shape so that upper and lower side edges can be respectively inserted into the engagement grooves, the first engagement grooves and the corresponding second engagement grooves. In addition to the above features, the invention according to claim 2 is characterized in that at least a space between the upper wall and the lower wall adjacent to the reinforcing bar is filled with a lightweight foam material and held. It is characterized by.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below based on embodiments of the present invention illustrated in the accompanying drawings.

In the accompanying drawings, FIG. 1 is a perspective view of a main part of a pit provided with a pit cover of the present invention, FIG. 2 is an enlarged sectional view taken along line 2-2 of FIG. 1, and FIG. 3 is an enlarged view taken along line 3-3 of FIG. Sectional view, FIG.
2 is a sectional view similar to FIG. 2 showing an example of changing the installation position of the connecting bar, FIG. 5 is a sectional view similar to FIG. 2 showing an example of filling with a foam material, and FIGS. FIG. 13 is a cross-sectional view similar to FIG. 2, showing another embodiment of the pit lid in which the cross-sectional shapes of the edge and the engagement groove are changed.

First, in FIG. 1 to FIG.
A groove-shaped pit P extending in a predetermined direction is recessed, and a lid mounting stepped portion 2 framed by an edge frame material having an L-shaped cross section is provided at a peripheral portion on both sides of the opening 1 of the pit P. It is provided recessed from the installation surface F. A plurality of pit lids T arranged in a row so as to close the opening 1 of the pit P are placed and supported on the lid mounting step 2.
Is substantially flush with the installation surface F, and constitutes a walking surface together with the installation surface F.

The lid body Tm of each pit lid T has a rectangular upper wall 3, a rectangular lower wall 4 whose upper surface is opposed to the lower surface of the upper wall 3 with a gap, and an upper wall 3 and a lower wall. A plurality of connecting walls 5 extending in a direction crossing the pits P so as to integrally connect the four members with each other are made of a metal material such as aluminum.

On the lower surface of the upper wall 3 between the adjacent connecting walls 5, 5, a large number of openings are formed on at least one end surface (both end surfaces in the illustrated example) of the upper wall 3 and extend in parallel with the connecting wall 5. V-shaped first engagement grooves 3a are close to each other (adjacent in the illustrated example)
The lower wall 4 is provided on the upper surface of the lower wall 4.
A large number of V-shaped second engagement grooves 4a which open at least on one end surface (both end surfaces in the illustrated example) and extend in parallel with the connecting wall 5 are provided in parallel with the plurality of first engagement grooves 3a, respectively. Have been. The upper and lower edges of the reinforcing bar L formed in a strip shape from a metal material are inserted into each of the first engagement grooves 3a and the corresponding second engagement grooves 4a. The upper and lower edges of the reinforcing bar L correspond to the corresponding engaging grooves 3a, 4a.
Is formed in a tapered shape so as to conform to the V-shaped cross section of FIG.

The lid main body Tm of the pit lid T is integrally formed by extrusion molding or drawing molding, or the upper wall 3, the lower wall 4, and the connecting wall 5, which are separately manufactured, are integrally connected to each other by welding or the like. And assembled. Further, when a part of the lid body Tm is reinforced, the first and second engagement grooves 3 of the upper wall 3 and the lower wall 4 corresponding to the part to be reinforced.
The upper edge and the lower edge of the reinforcing bar L are inserted from one of them into a and 4a. The upper wall 3 and the lower wall 4 as shown in FIG.
(Especially the opening edges of the engaging grooves 3a and 4a) by crimping 6, or a strip-shaped edge plate (not shown) for retaining is fixed to the end surfaces of the upper wall 3 and the lower wall 4. Alternatively, it is performed by an appropriate fixing means such as welding or bonding the edge of the reinforcing bar L to the upper wall 3 and the lower wall 4. on the other hand,
Lid body T of reinforcing bar L inserted into each engagement groove 3a, 4a
The vertical movement with respect to m and the horizontal movement (that is, the horizontal movement) in the direction crossing the grooves 3a and 4a are regulated by the engagement between the edge of the reinforcing bar L and each of the engagement grooves 3a and 4a.

In the pit cover T obtained in this manner, the reinforcing bar L has upper and lower edges formed by the first engaging groove 3a of the upper wall 3 and the second engaging groove 4a of the lower wall 4. The reinforcement bar L can be easily fixed between the upper wall 3 and the lower wall 4 simply by preventing the reinforcing bar L from being pulled out in the insertion direction because the positioning bar can be positioned and held in the vertical direction and the horizontal direction simply by simply inserting the reinforcing bar L into the insertion wall. Moreover, FIG.
As shown in the above example, the reinforcing mode of the lid main body Tm can be easily changed as needed simply by appropriately changing the number of used reinforcing bars L and the insertion position, so that the thickness of the lid main body Tm is changed. The bending stiffness can be effectively increased as necessary without performing.

Thus, a pit lid of a constant thickness with a necessary portion sufficiently reinforced can be easily obtained without having to prepare many kinds of pit lids in advance.
Since they are simple flat plates (strips) which are not bulky before assembling, their handling such as production, storage and management is good. Also, since a number of adjacent engaging grooves 3a and 4a are arranged in parallel on the upper wall 3 and the lower wall 4, the ribs formed between the adjacent grooves 3a and 4a can exert a rib effect. Therefore, the bending rigidity of the upper wall 3a and the lower wall 4a can be further increased.

In FIG. 5, between the upper wall 3 and the lower wall 4,
An embodiment in which a lightweight foam material 8 is filled and held in at least adjacent spaces S, S (all spaces in the illustrated example) of the reinforcing bar L is shown. When filling such a foaming material 8, for example, a foaming agent such as a urethane foaming agent that expands when exposed to air may be injected into each of the space portions and foamed and solidified. According to this embodiment, by filling and holding the foam material 8, the degree of fixing (stability) to the upper wall 3 and the lower wall 4 of the reinforcing bar L is increased accordingly, and the overall strength of the pit lid T can be improved. it can. Moreover, if the filling space of the foam material 8 is made large as shown in the figure, the density of the pit lid T can be reduced (therefore, buoyancy is increased). In the case where the lid T is accidentally dropped, the lid T can be floated, and the collection thereof becomes easy.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various embodiments are possible within the scope of the present invention. For example, in the above-described embodiment, the engaging grooves 3a and 4a of the upper wall 3 and the lower wall 4 are V-shaped grooves, and the upper and lower edges of the reinforcing bar L are tapered corresponding to the V-shaped grooves. As shown in FIG. 6, each of the engaging grooves 3a and 4a may be formed into a square groove shape to flatten the end surfaces of the upper and lower edges of the reinforcing bar L, and each of the engaging grooves 3a and 4a may be formed as shown in FIG. As shown in FIG. 8, the upper and lower edge portions of the reinforcing bar L may be formed in a circular arc shape, and the engaging grooves 3a and 4a may be formed in a dovetail shape as shown in FIG. The upper and lower edges may be formed to have a widened shape. In the embodiment of FIG. 8, the connection strength between the upper wall 3 / lower wall 4 and the reinforcing bar L can be improved. Further, the mounting of the cover main body Tm of the reinforcing bar L may be appropriately performed at the construction site of the pit P, or may be performed at a pit cover assembling factory. Further, in the above-described embodiment, the opening of the groove-shaped pit is closed by the pit lid T. However, the pit lid of the present invention is not limited to the opening of the vertical pit recessed on the installation surface, It may be used to close the openings of various tanks embedded in the surface. Further, in the above embodiment, the lid body Tm
(The upper wall 3, the lower wall 4, the connecting wall 5) and the reinforcing bar L are shown to be formed of a metal material such as aluminum. At least one (or a part) of the lid body Tm and the reinforcing bar L is Materials other than metal materials (for example, FRP materials, plastic materials, etc.)
May be formed.

[0017]

As described above, according to the invention of each claim,
The reinforcing bar can be positioned and held in the vertical and horizontal directions simply by inserting the upper and lower edges of the reinforcing bar into the first engaging groove of the upper wall and the second engaging groove of the lower wall. The reinforcement bar can be easily fixed between the upper wall and the lower wall simply by retaining in the direction, and the reinforcement mode of the pit lid can be changed simply by appropriately selecting the number of used reinforcement bars and the insertion position. Since the pit lid can be easily selected as needed, the bending rigidity thereof can be effectively increased as necessary without changing the thickness of the pit lid. Therefore, a pit lid of a certain thickness with necessary parts sufficiently reinforced can be easily obtained without having to prepare many kinds of pit lids in advance. Since they are in a flat plate shape (strip plate shape), they are easy to manufacture and easy to handle such as storage and management, which can greatly contribute to cost reduction as a whole. Also, if a number of engaging grooves are arranged in parallel on the upper wall and the lower wall, the ridge formed between the adjacent grooves can exert a rib effect, so that the bending rigidity of the upper wall and the lower wall is reduced. Can be further enhanced.

According to the second aspect of the present invention, the degree of fixing (stability) to the upper and lower walls of the reinforcing bar is increased by the filling effect of the foam material, and the overall strength of the pit lid can be improved. it can. In addition, since the buoyancy of the pit lid can be increased by enlarging the filling space of the foam material, for example, when the lid is accidentally dropped into a pit where liquid is accumulated, the lid can be floated and collected. It can be easy.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part of a pit provided with a pit cover according to the present invention.

FIG. 2 is an enlarged sectional view taken along line 2-2 of FIG. 1;

FIG. 3 is an enlarged sectional view taken along line 3-3 in FIG. 1;

FIG. 4 is a cross-sectional view similar to FIG. 2, showing an example of changing the installation position of a reinforcing bar.

FIG. 5 is a sectional view similar to FIG. 2, showing an example of filling with a foam material;

FIG. 6 is a sectional view similar to FIG. 2, showing another embodiment of the pit lid in which the cross-sectional shapes of the edge of the reinforcing bar and the engaging groove are changed.

FIG. 7 is a sectional view similar to FIG. 2, showing still another embodiment of the pit lid in which the cross-sectional shapes of the edge of the reinforcing bar and the engaging groove are changed.

FIG. 8 is a sectional view similar to FIG. 2, showing still another embodiment of the pit lid in which the cross-sectional shapes of the edge of the reinforcing bar and the engaging groove are changed.

[Explanation of symbols]

 F: Installation surface L: Reinforcing bar P: Pit T: Pit lid Tm: Lid body S: Space 1 Opening 3 Upper wall 3a First engagement groove 4 Lower wall 4a Second engagement groove 5 Connection wall 8 Foam

Claims (2)

[Claims] 1. A lid body (Tm) supported by a peripheral portion of an opening (1) formed on a walkable installation surface (F) so as to close the opening (1) is provided on an upper wall (3). A lower wall (4) whose upper surface is opposed to the lower surface of the upper wall (3) with an air gap, and a gap between the upper wall (3) and the lower wall (4) are arranged side by side with each other. In a reinforcing structure of a lid main body in a pit lid constituted by a plurality of connecting walls (5) integrally connected to each other, a lower surface of the upper wall (3) is mutually spaced between adjacent connecting walls (5, 5). A plurality of first engagement grooves (3a) arranged in parallel with each other, and a plurality of second engagement grooves (3a) arranged in parallel on the upper surface of the lower wall (4) corresponding to the first engagement grooves (3a). The strip plate is formed such that upper and lower side edges can be respectively inserted into the engagement grooves (4a), the first engagement grooves (3a), and the corresponding second engagement grooves (4a). Formed a, characterized in that it comprises at least one reinforcement bar (L), the reinforcing structure of the lid body in the pit lid. 2. A space (S) between the upper wall (3) and the lower wall (4) at least adjacent to the reinforcing bar (L).
The structure for reinforcing a lid body in a pit lid according to claim 1, wherein a lightweight foam material (8) is filled and held.