JPH0357690B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a partition plate in a conduit, and when installing a perforated pipe through which a plurality of cables are inserted into a manhole, the tension at the time of cable insertion, the accommodation space, etc. The present invention relates to a block-shaped duct sleeve suitable for perforated pipes.

[Conventional technology]

The conventional device for connecting pipes and manholes consists of 50 cables 1 as shown in the structural diagram in Fig. 5.
Since the structure consisted of 51 pieces per line, 1 pipe line, and 1 duct sleeve 52, the number of articles and the amount of work were large, which was economically disadvantageous.

In addition, if a perforated pipe 61 is developed in which a partition plate 62 is provided in the conduit shown in the structural explanatory diagram of FIG. 6, which has the advantage of improving economical efficiency and workability by consolidating the cross section, as shown in FIG. It is also necessary to develop a duct sleeve 63 for a perforated pipe. 60 indicates a cable.

On the other hand, the requirements for the duct sleeve are that the current tools inserted into the duct opening can be used as is, that the cable laying tension is below the allowable value, and that the structure allows the cable to be accommodated within the conventional storage space. I can give you 3 points.

[Problem that the invention seeks to solve]

It is difficult for conventional duct sleeves to satisfy the above-mentioned conditions for duct sleeves. The reason for this will be explained, for example, with respect to a simple duct sleeve for a porous pipe whose structural outline is shown in FIGS. 7A and 7B. 70 is a perforated pipe duct sleeve, 71 is a perforated pipe, 72 is a cross section of a perforated pipe, and 73 is a cross section of a duct opening. Several tools are available for each application category, such as installation, movement prevention, and fixation, as duct opening installation tools mentioned in duct sleeve conditions, but the factors that affect the application of current tools include:
Two points are mentioned: the duct axis spacing L ₁ and the duct opening insertion length L ₂ of the perforated pipe duct sleeve 70 shown in FIG.
Regarding the former duct axis spacing L ₁ , for example, B of the movement prevention tool whose structure is shown in Fig. 8A and B.
The cable movement prevention fitting 80 allows the cable to remain the same as the current 15
It is necessary to take cm. In addition, 81 is a cable,
82 is a manhole, and 83 is a duct opening. Regarding the latter duct opening insertion length _L2 , for example, it is necessary to provide a length of 20 cm using a metal bell mouth of a laying tool whose structure is shown in FIGS. 9A to 9C.
Note that changing these values is not economical because it affects the application of various other tools.
Due to this limiting condition, the gap H shown in Figure 7 has a lower limit value, but when inserting a cable through the gap H, it is necessary to keep the tension at the time of insertion below the allowable value. Therefore, it is necessary to increase the length of the duct sleeve. However, an increase in the length of the duct sleeve is economically disadvantageous, such as deterioration in the manufacturability of the duct sleeve and an associated increase in costs and earthwork costs.

For the reasons stated above, it is desired to realize a duct sleeve for a porous pipe that economically satisfies the above three conditions.

[Means for solving problems]

In order to solve the conventional problems and satisfy the requirements for a duct sleeve for a perforated pipe, the present invention has an eccentric duct opening for cable entry fixed via a sealant and a stopper at the tip of an outer cylinder that connects a perforated pipe to a manhole. Structure of a block-shaped duct sleeve comprising a plate and a block that is rotatably attached to and detached from an eccentric duct opening of the plate and has a cable insertion opening eccentric to a rotating shaft through which a cable inserted into the eccentric duct opening is inserted. It is characterized by

[Effect]

The present invention has been developed to make perforated pipes movable in response to conduit expansion and ground subsidence, to maintain watertightness without damaging the connection parts, and to reduce the tension and cable tension during cable insertion in order to reduce the length of the duct sleeve. The position of the duct opening can be changed for each accommodation space. Embodiments will be described in detail below based on the drawings.

〔Example〕

FIGS. 1A to 1C are longitudinal cross-sectional views showing the main structure of an embodiment of the present invention. Outer cylinder 1 is manhole 13
and the porous pipe 10, and its base end is inserted into the duct notch when constructing the manhole 13, and is easily installed.

On the other hand, an elastic ring 2 made of rubber is watertightly attached to the inner peripheral surface of the tip.
The end of the porous pipe 10 is inserted and connected in a watertight manner through the . Therefore, water stoppage is ensured without restricting movement of the perforated pipe 10 due to temperature expansion and contraction, earthquakes, and ground subsidence, and seismic resistance is improved.

At the tip of the outer cylinder 1, a plate 3 has a sealant 6 and a stopper 7 (see 11 in Fig. 1C for the structural diagram).
has been fixed through. The plate 3 has a duct hole 12, and the block 4 is attached to the duct hole 12 via an O-ring 5 and an M10 hexagon socket head bolt 9. Also, because of this structure, the block 4 can be easily removed from the plate 3, so if the block 4 is reversed and attached to the plate 3 again, two different positions of the duct opening 14 can be taken. The structure of the block 4 is as shown in FIGS. 2A to 2C, which show the left side, front side, and right side view, respectively.

FIGS. 3A to 3F are diagrams illustrating an embodiment in which the block 4 is used to insert a cable. The same reference numerals as in FIG. 1 indicate the same parts. When the duct surface 30 in FIG. 3A is viewed from inside the manhole, it becomes as shown in FIG. 3E. When the cable is inserted, the hole in the porous pipe 10 and the duct opening of the duct hole 12 are at the same level in order to reduce the tension during the cable insertion. After the cable has been inserted, block 4
The block 4 is removed from the duct hole 12 as shown in FIG. 3B, and then the block 4 is rotated in the opposite direction as shown in FIG. 3C and reinstalled as shown in FIG. 3D. At this time, the duct surface 30 becomes as shown in FIG. 3F. Naturally, the length of the duct sleeve is designed so that the cable fits within the accommodation space even after the block is reversed, but since there is no need to take into account the increase in tension when the cable is inserted, if this is not taken into account, the present invention It can be much shorter than without. Furthermore, since the duct axis spacing can be maintained at a specified value or higher, conventional tools can be used as is.

The outline of the present invention described above will be summarized and explained below.

When designing a duct sleeve for a perforated pipe, two steps can be considered. The first step is to insert the cable (Figure 3A), and the second step is to fit the cable after the cable has been inserted within the specified radius of curvature (six times the outer diameter of the cable), and to prevent the cable from moving to the duct opening. This is the step of installing a tool or the like at the duct opening to accommodate the cable (FIGS. 3B to 3D).

The key point in the cable insertion stage is to reduce the tension as much as possible during cable insertion.
The key point in the cable accommodation stage is to install the movement prevention fittings, etc. at the duct opening 1 as shown in Figure 4.
4 has an installation space 40 for tools. However, when considering the installation space 40 for tools, it is inevitable that each duct opening 14 must be spaced apart, so a level difference LD occurs between the hole of the porous pipe 10 and the duct opening 14, and the tension when inserting the cable increases significantly. It will increase to .
In addition, since it is necessary to ensure the duct insertion length (L ₂ in Fig. 7) corresponding to the tool inserted into the duct opening 14, the duct axis spacing (Fig. 7)
In addition to L ₁ ), the tension when inserting the cable increases due to the geometrical restriction of the duct insertion length L ₂ .

As described above, the perforated duct sleeve has contradictory requirements at the cable insertion stage and the cable accommodation stage.

The simplest form (Figure 7) that satisfies this is to space the duct openings at regular intervals (fixing the duct openings in the state in which the cables are accommodated, as shown in Figure 3F), and the tension caused by this when the cables are inserted. The increase is intended to relatively reduce the level difference by increasing the duct sleeve length. However, in this case, the length of the duct sleeve becomes long, so it cannot be said to be economical. Therefore, the present invention is directed to FIGS. 3A to 3F.
As shown in Figure 2, by adopting a block configuration so that the position of the duct opening can be changed when inserting the cable and when storing the cable, we are able to satisfy the conflicting requirements when inserting the cable and when storing the cable in a compact form. did.

〔Effect of the invention〕

As described above, the present invention fixes the proximal end of the duct sleeve to the side wall of the manhole, and makes the end of the porous pipe movable via the elastic ring tightly attached to the distal end of the duct sleeve that extends outside the manhole. It has the advantage of maintaining watertightness without being damaged even by expansion and contraction due to temperature changes, earthquakes, and ground subsidence. In addition, by using this duct sleeve, the tension when inserting the cable can be reduced to less than the required value. After inserting the cable, by rotating its position 180 degrees, the cable can be stored in the specified storage space, and the duct opening axis can be Since the spacing can be maintained as before, there is an advantage that current laying tools can be used. Also, when designing the length of the duct sleeve, you only need to consider the cable fitting within the space, not the cable insertion tension.
This has the advantage that the length of the duct sleeve can be made compact. This is economically advantageous as it improves manufacturability, reduces costs, and reduces civil engineering costs.

[Brief explanation of drawings]

Figures 1A and B are side views and sectional views of an embodiment of the present invention, Figures 2A to C are structural diagrams of blocks of the invention, and Figures 3A to F are diagrams explaining the embodiment of the invention. , Fig. 4 is a diagram showing the relationship between the duct opening and the tool installation space, Fig. 5 is a structural schematic diagram of a conventional duct sleeve, Fig. 6 is a structural schematic diagram of a duct sleeve for perforated pipes, and Fig. 7 A and B are schematic diagrams. FIGS. 8A and 8B are schematic diagrams of the structure of a duct sleeve for a simple porous pipe, FIGS. 8A and 8B are schematic diagrams of the structure of a B-type cable movement prevention fitting, and FIGS. 9A to C are schematic diagrams of the structure of a bell mark for metal. 1...Outer cylinder, 2...Elastic ring, 3...Plate, 4...Block, 5...O ring, 6...Sealant, 7...Stopper, 8...M8 screw, 9...
...M10 hexagon socket head bolt, 10... Porous pipe, 11
...Stopper cross section, 12...Duct hole, 13...
... Manhole, 100 ... Duct sleeve, 30
... Duct surface, 31 ... Cable, 14 ... Duct opening, 40 ... Tool installation space, 50 ... Cable, 51 ... Conduit, 52 ... Duct sleeve,
60... Cable, 61... Porous pipe, 62... Partition plate, 63... Duct sleeve, 70... Porous pipe duct sleeve, 71... Porous pipe, 72... Porous pipe cross section, 73... Duct opening cross section , 80...B type cable movement prevention fitting, 81...cable, 82...
...Manhole, 83...Duct hole.

Claims (1)

[Scope of Claims] 1. A duct sleeve for cable installation in which a partition plate is provided in a conduit and a perforated pipe through which a plurality of cables are inserted is connected to a manhole by an outer cylinder, wherein the duct sleeve is arranged on the manhole side of the outer cylinder. a plate having an eccentric duct opening for cable entry fixed via a sealant and a stopper at one end of the plate; and a block having a cable insertion port eccentric to the axis, and an elastic ring is attached to the inner circumferential surface of the other end of the outer cylinder in a watertight manner to the end of the porous tube. Features a block-shaped duct sleeve.