JPH0214265Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a handhole for underground cables, that is, a concrete basement installed for wiring, maintenance, and inspection of communication cables, electrical cables, etc. buried underground. be.

Conventionally, underground chambers made of concrete, etc. have been set up for cable wiring, maintenance, inspection, etc. at each point where cables buried underground are introduced underground, branched out underground, connected, bent, etc. This is generally called a hand hole. In recent years, electrical wiring for communications and electricity has been moved to underground cables due to the ease of recovery in the event of a disaster and the aesthetic appearance of the city. Cables are routed after connecting them with manufactured flexible conduit, steel pipe, humid pipe, etc. However, since the facility is sometimes installed on roads with heavy traffic, hand holes are also formed at the concrete factory, transported to the site, and assembled. It's starting to be done. The size of the hand hole varies depending on the type and number of cables to be wired, such as high-voltage cables and low-voltage cables, and the number of branches from these cables. The handhole body is generally divided into upper and lower halves to form an upper body and a lower body, which are combined with a lid and its receiving frame that are attached to the opening on the top surface. It is configured like this. Since each part except the lid is molded with concrete, it is heavy, and in order to facilitate transportation and assembly work, engaging hooks are installed on the top surface of each member, as seen in Publication of Utility Model Publication No. 55-45711. Burying and engaging mechanisms have been proposed, and in general, hooks for hanging have been buried in the outer wall or top surface to facilitate transportation.

However, in the case of hand holes, two or more may be buried next to each other, and if hanging hooks are protruded from the outer wall surface, gaps will be created between the hand holes, making burying time-consuming. It was necessary to remove the hooks on site, and care had to be taken not to damage the hooks when curing and storing products at concrete factories. In addition, in order to suspend or place the cable exposed inside the hole on the inner wall surface of the hand hole, it is necessary to attach a receiving object equivalent to the arm of a utility pole to the wall surface. When wiring inside, a partition wall such as plasterboard may be installed to separate and insulate the two, and in order to attach these brackets and boards to the wall, holes are drilled and fasteners are embedded, or It was necessary to drive concrete studs. Furthermore, after burying the handhole, the cable is pulled in through the opening and wired, but in order to prevent damage when pulling the cable in, it is necessary to attach a pulley to the opening, etc., and a chain fixing hook for locking the lid is used. In addition, in large hand holes, it is necessary to fix ladders to enter and exit the hand hole for work, and to place scaffolding hardware on the inner wall surface. Therefore, it was troublesome to bury and deliver these mounting brackets according to the specifications.

In view of the current situation, the present invention has been made to facilitate on-site work such as transporting and burying hand holes, installing flexible conduit, etc., pulling in cables, etc., and wiring inside boxes. The following will explain the embodiments shown in the drawings.

As shown in Figs. 1 and 2, the hand hole according to the present invention includes a lower main body 1 formed of concrete and forming a rectangular box with a bottom and whose upper surface is completely open.
The ceiling surface has a manhole for workers to enter and exit, the bottom surface is completely open, and the rectangular main body upper part 2 is placed and joined to the main body lower part 1, and the main body upper part 2 opens to the ceiling surface. It consists of each member of a cylindrical receiving frame 3 that fits into the manhole and supports the lid 4 in the upper opening, and at least one cylindrical support frame 3 is formed on each side of the inner wall of the lower part 1 and the upper part 2 of the main body molded from the concrete. Inserts 5 are embedded in the inner wall surface of the receiving frame 3 in at least three or more equal locations, that is, in four or more locations in total, and are opened in the inner wall surface. The number and position of the inserts 5 may be at least 3 at positions roughly dividing the inner circumference by three, but depending on the size of the handhole body, the inserts 5 may be buried in one side of the inner wall as shown in Fig. 2. The position of the insert 5 on the upper part of the main body 2 should be on the vertical line of the insert 5 provided on the lower part 1 of the main body, and the position of the insert 5 should be on the vertical line of the insert 5 provided on the lower part 1 of the main body. Inserts 5 are buried at equal intervals at a plurality of locations in the direction.

Note that a thin wall section 6 is provided on the side wall of the lower part 1 of the main body, and this is because flexible conduit pipes, fume pipes, etc. for cable wiring are installed at the site so as to open into the inner wall surface. The hole is made to facilitate drilling, and the position of the pipe is determined in advance.
If the thickness and number are known, the holes will be drilled at the concrete factory before shipping, so the thin wall part 6
is not a constituent requirement of the present invention. Further, the receiving frame 3 is mainly manufactured in an annular shape according to the shape of the lid 4. Although a square lid body is sometimes used,
In general, a circular lid is often used to prevent the lid 4 from falling into the hand hole, and when installed on a road, vehicles may pass over the lid 4, so the lid 4 is made of durable cast iron, so if the lid is placed directly on the concrete surface, the concrete will be damaged, so the receiving frame metal fittings are attached to the placing part to protect it, and the insert 5 is attached to the inner wall of the lid.
will be buried in at least three locations.

Since the present invention is constructed as described above, each member of the lower body 1, upper body 2, and receiving frame 3 of the hand hole molded in a concrete factory does not have protruding parts such as hooks unlike conventional molded products. Therefore, each component is stacked one on top of the other, requiring less land area for curing and storing the concrete, and when transporting it, it is sufficient to screw a hook bolt etc. into the insert 5 that opens on the inner wall surface, and during installation. Since there are no hooks or other protruding objects on the exterior wall surface, if two or more handholes are installed together, they can be installed closely together, and the holes dug during burial are also narrower than when hooks are installed on the outside. There are advantages. After installation, the insert 5 provided on the inner wall of the hand hole body can be used to attach scaffolding fittings for lifting and lowering, and to attach receiving fittings for suspending or placing cables directly or with bolts to the insert 5. It can be easily attached to a vertical metal structure made of an L-shaped angle, or by using a vertical metal fitting with an insulating board such as a plaster board attached to an insert in the same manner as described above. In addition, when wiring the cable, by fixing the pulley using the insert 5 buried in the inner wall surface of the receiving frame 3, the cable can be easily drawn into the hand hole and wired without damaging it. After removal, it has many uses, such as being able to screw together a hook bolt for attaching a chain or the like connecting the lid 4 and the receiving frame 3, or attaching a fixing bolt for a ladder or the like.

Although the handhole main body has been shown in an embodiment in which it is divided into upper and lower halves, it may be further divided and molded depending on the size, and in that case, an insert may be buried in the inner wall surface for each member. The type of insert is not particularly limited, and it is best to use one that is configured to prevent concrete from entering the insert, for example, one with a simple lid.For strength, it is better to use a hook bolt for hanging. Since there is no need to worry about the insert fitting or falling off during hanging transportation and installation, a relatively inexpensive insert can be used.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is an assembled perspective view, and FIG. 2 is a vertical sectional side view of FIG. 1. 1... lower body, 2... upper body, 3... receiving frame, 4... lid, 5... insert.

Claims (1)

[Scope of utility model registration request] The lower part 1 of the main body is formed of concrete and forms a rectangular box with a bottom and the upper surface is completely open.
a rectangular main body upper part 2 joined to the main body upper part 2;
It is composed of a receiving frame 3 that supports a lid 4 on the upper opening, which fits into a manhole opening in the ceiling of the main body and is attached so as to be openable and closable. This hand hole for an underground cable is characterized in that inserts 5 are buried in at least three places in the inner wall surface of the receiving frame 3 and are opened in the inner wall surface.