JP2007113197A - Manhole structure and cable construction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manhole structure and a cable construction method of constructing a cable without providing a connection section from a manhole on the halfway of construction path. <P>SOLUTION: This manhole 1 is composed of a manhole body part 2 whose inside is formed like a hollow box, a manhole neck part 3 having a manhole in hole part 5 in the inside, and a slit part 4 for cable incoming line having a slit communicating from an upper part to a lower part. A plurality of pipe passages 8 storing the cable 9 in the underground part are connected with the manhole body part 2. An upper part on the ground surface and the inside of the manhole body part 2 are mutually communicated through the inside of the manhole neck part 3 and the slit part 4 for cable incoming line, and length of the manhole in hole part 5 and the slit part 4 for cable incoming line is longer than diameter of allowable bending of the cable 9. After the cable 9 comes into the pipe passage on one side from one end side, and the cable 9 comes into the pipe passage on the other side from the other end side by this configuration. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a manhole structure in which a plurality of conduits that are buried in the ground and accommodate cables are connected, and a cable laying method in the manhole. Specifically, one cable is longer than the diameter of the cable and the other is longer than the allowable bending diameter of the cable. It is possible to lay a cable from a manhole installed in the middle of a route to be laid without providing a connection point in a conduit for cable laying.

  For reasons of safety and harmony with the landscape, various cables for electric power and communication are laid in pipelines provided in the ground. FIG. 13 is a schematic diagram showing a state in which the pipe line 8 is provided in the ground between the utility pole A32 and the utility pole B33, and the manhole 50 is further provided. A cable 9 is laid in the pipeline 8.

  The manhole 50 shown in FIG. 13 is provided for performing various operations such as laying and connecting the cable 9 laid in the pipe line 8 provided in the ground. Below, the structure of the conventional manhole 50 is demonstrated using figures. 14 to 16 are explanatory views showing a conventional manhole 50.

  FIG. 14 is a perspective view showing a conventional manhole 50, which is shown by a broken line in a partially transparent state for explanation. FIG. 15 is a plan view showing a state of the manhole 50 as viewed from above, and is shown by a broken line in a partially transparent state for explanation. In FIG. 15, a manhole cover 54 described later is not displayed.

  FIG. 16 is a cross-sectional view taken along the line BB in FIG. 15 and shows a state where the manhole 50 is buried in the ground such as the sidewalk 10 and the manhole cover 54 is closed.

  As shown in FIGS. 14 to 16, the manhole 50 includes a manhole body 52, a manhole neck 53, and a manhole cover 54.

  The manhole body 52 is formed in a hollow box shape. The manhole body 52 includes a neck hole 52a on the upper surface. Moreover, the manhole main body part 52 is provided with the hole part 52b for pipelines in the side surface which faces. Further, the manhole main body 52 includes a cable installation tool 52c inside. The manhole main body 52 is formed of, for example, a reinforcing bar concrete.

  The manhole neck 53 is formed in a hollow cylindrical shape, and is fixed to the upper portion of the manhole main body 52 by a neck hole 52a. The cavity inside the manhole neck 53 and the neck hole 52 a are formed in the same cross-sectional shape, and the upper part of the manhole neck 53 and the inside of the manhole main body 52 communicate with each other through the inside of the manhole neck 53.

  The cavity inside the manhole neck 53 is referred to as a manhole entrance 55. The manhole neck 53 is formed of, for example, a reinforcing bar concrete.

  Further, as indicated by an arrow m in FIG. 14, a manhole cover 54 can be opened and closed at the upper end of the manhole neck 53. The manhole cover 54 can block the manhole entrance 55.

  Further, as shown in FIGS. 14 to 16, the pipeline 8 is connected to each pipeline hole 52 b of the manhole body 52. Each cable 9 is laid in the pipe line 8. The laid cable 9 is installed in the manhole main body 52 by the cable installation tool 52c.

  Further, as shown in FIG. 13, there are many bent portions 31 generated in the pipe line 8 so as to avoid the important underground buried object 30.

  When laying the cable 9 in the conduit 8 from the utility pole A32 to the utility pole B33, it is desirable to lay all the paths from the utility pole A32 to the utility pole B33 with the same cable 9.

  However, when the cable 9 is inserted (entered) into the conduit 8, tension and lateral pressure are generated in the cable 9 due to friction between the surface of the cable 9 and the conduit 8. For this reason, the cable 9 cannot be inserted with the tension and the side pressure exceeding the limit values of the cable 9.

  As shown in FIG. 13, when the bent part 31 exists in the pipe line 8, the tension | tensile_strength and side pressure which arise in the cable 9 become still larger, and the distance which can wire the cable 9 becomes short. Further, as the distance between the utility pole A32 and the utility pole B33 becomes longer, the drawing tension and the side pressure generated in the cable 9 increase, and the entry becomes difficult.

  For this reason, for example, by connecting another cable 9 from the manhole 50 in the middle of the route for laying the cable 9 toward the utility pole A32 and the utility pole B33, and connecting the two cables 9 in the manhole 50, the utility pole It is necessary to lay the cable 9 from A32 to the utility pole B33.

  In addition to the above, a cable laying method for reducing the friction coefficient in the pipeline when laying underground cables has been proposed (see, for example, Patent Document 1).

  The cable laying method disclosed in Patent Document 1 lays a cable while attaching ring-shaped slip lines at a predetermined interval immediately before the cable is inserted into the pipe. By laying in this way, the friction coefficient in the pipeline when laying the cable is reduced, and the laying limit length in the pipeline is improved.

  Furthermore, a manhole structure for inserting a cable into the manhole with the manhole cover closed has been proposed (see, for example, Patent Document 2).

  The manhole structure disclosed in Patent Document 2 includes a receiving frame arranged at the upper end of the manhole and a manhole cover placed on the receiving frame. In addition, a first cable insertion hole is provided in the manhole cover, and a second cable insertion hole is provided in the blocking portion provided in the receiving frame.

  By providing such a configuration, the cable can be inserted into the manhole with the manhole cover closed.

  In addition, a manhole neck and a manhole body for easily connecting and repairing cables laid in the ground have been proposed (see, for example, Patent Document 3).

  In the manhole neck and manhole main body disclosed in Patent Document 3, the slant wall of the manhole neck is formed in a curved surface convex outward. In addition, a cable branch is installed in a space formed by the upper surface of the manhole body and the neck of the manhole. Furthermore, a slit is provided in the ceiling part of the manhole body, and the cable is routed through the slit.

  By providing such a configuration, the manhole neck and the manhole main body disclosed in Patent Document 3 enable the worker to easily perform cable connection / repair work without getting down to the basement. .

Japanese Patent Application Laid-Open No. 07-046732 Japanese Patent Laid-Open No. 2003-268795 JP-A-11-172714

  However, the above-described method of laying a cable connected in the middle of a pipe has the following problems. Since it is necessary to perform cable connection work in the manhole, there is a problem that construction time and necessary materials increase. Also, in order to connect the cable, it is necessary to provide an extra length portion in consideration of the thermal expansion and contraction of the cable, and an extra space for accommodating the extra length portion is required in the manhole. There's a problem.

  Furthermore, there is a problem that after the operation of the equipment, unnecessary stress is applied at the connection point of the cable, increasing the cause of the accident.

  In addition, the cable laying method for reducing the coefficient of friction between the cable and the pipe described in Patent Document 1 requires that ring-shaped sliding wires be attached at predetermined intervals immediately before the cable is inserted into the pipe. There is a problem that the installation work becomes very complicated.

  In addition, the manhole structure described in Patent Document 2 enables a cable used for inspection or the like to be inserted into a manhole with the manhole cover closed, with respect to two connected pipe lines. It cannot be used to connect cables. Therefore, it is not possible to lay the same cable having no connection place in the pipeline for cable laying.

  In addition, the manhole neck and manhole main body described in Patent Document 3 are configured to allow the operator to perform cable connection / repair work without getting down to the basement, and with respect to two pipe lines connected to the manhole. It cannot be used to connect cables. Therefore, it is not possible to lay the same cable having no connection place in the pipeline for cable laying.

  The present invention has been made to solve such a problem, and provides a manhole structure and a cable laying method capable of laying a cable from a manhole in the middle of a cable laying route without providing a connection point. For the purpose.

  In order to solve the above-described problem, the manhole structure according to the present invention is formed in a manhole structure in which a plurality of conduits for accommodating cables are connected and embedded in the ground together with the conduits, and the inside is formed in a hollow box shape. A main body part that is located underground and to which a plurality of pipelines are connected; a cable entry part located at the upper part of the main part; and a cable entry part lid; Is longer than the allowable bending diameter of the cable, and has a cavity that allows communication between the upper part of the ground and the inside of the main body. The cable entry line lid opens and closes the cavity of the cable entry line. It is characterized by covering freely.

  In the manhole structure according to the present invention, the cable is inserted into the two pipe lines connected to the main body of the manhole as follows. First, open the cable entry cover. Then, from the upper part of the ground, one end of the cable is inserted into the main body from the cavity of the cable entry part. Thereafter, the cable is inserted into one of the pipes to be connected from one end side that is inserted into the main body.

  Thereafter, the other end of the cable is inserted into the inside of the main body from the cavity of the cable entry portion from the upper part of the ground. After that, the cable is inserted into the other incoming line from the other end side that is inserted into the cable body.

  When a cable is inserted from the upper part of the ground into the main body part, the cable connected to one line is connected to one pipe line from one end and the other pipe is connected to the other pipe so that it remains on the upper part of the ground. The last part of the cable is formed in a semicircle. Since the cavity portion of the cable entry portion has a length longer than the allowable bending diameter of the cable to be accommodated, the cable can be inserted into the main body portion with the last portion formed in a semicircular shape.

  After putting all the cables inside the main unit, close the cable entry cover.

  In order to solve the above-described problem, the cable laying method according to the present invention is a cable in which a plurality of pipelines in which cables are accommodated are connected, and a cable is inserted into a pipeline from a manhole buried in the ground together with the pipeline. In the laying method, one end of the cable is inserted into the manhole from the upper part of the ground, the cable is inserted from one end of the cable inserted into the manhole into one of the pipes to be connected, and the other end of the cable is connected from the upper part of the ground. The cable is inserted into the manhole, and the cable is inserted from the other end of the cable inserted into the manhole into the other pipe line to be connected.

  In the cable laying method according to the present invention, one end of the cable is placed in the manhole. Thereafter, the cable is inserted from one end side inserted into the manhole into one of the inlet lines.

  Thereafter, the other end of the cable is placed inside the manhole. Thereafter, the cable is inserted into the other pipe line to be connected from the other end side inserted into the manhole.

  According to the manhole structure of the present invention, the cavity portion of the cable entry portion has a length longer than the allowable bending diameter of the cable to be accommodated. For this reason, in the method of inserting a cable from one end into one conduit and inserting the cable from the other end into the other conduit, the last part of the cable formed in a semicircular shape You can enter.

  Thereby, it becomes possible to lay a cable from the manhole in the middle of a cable laying path | route, without providing a connection location.

  According to the cable laying method of the present invention, after inserting a cable from one end into one conduit, connecting from the manhole in the middle of the cable laying route by connecting the cable from the other end to the other conduit It is possible to lay the cable without providing a place.

  Hereinafter, an embodiment of a manhole structure of the present invention will be described with reference to the drawings.

<Configuration example of manhole in this embodiment>
1 to 3 are explanatory diagrams illustrating an example of a manhole 1 according to the present embodiment. FIG. 1 is a perspective view showing a manhole 1, which is shown by a broken line in a partially transparent state for the sake of explanation. FIG. 2 is a plan view showing the manhole 1 as viewed from above, and is shown by a broken line in a partially transparent state for explanation. In FIG. 2, a manhole cover 6 and a slit cover 7 described later are not shown.

  FIG. 3 is a cross-sectional view taken along the line AA of FIG. 2 and shows a state where the manhole 1 is embedded in the ground such as the sidewalk 10 and the manhole cover 6 and the slit cover 7 are closed.

  As shown in FIGS. 1 to 3, the manhole 1 includes a manhole body portion 2, a manhole neck portion 3, a cable entry slit portion 4, a manhole cover 6, and a slit portion cover 7.

  The manhole body 2 is formed in a box shape having a hollow inside. A neck hole 2 a is provided on the upper surface of the manhole body 2. On the upper surface of the manhole main body 2, a slit hole 2b connected to the neck hole 2a is provided at a position facing the outer periphery of the neck hole 2a. Further, the manhole body 2 is provided with a duct hole 2c on the opposite side surface. Further, the manhole main body 2 includes a cable installation tool 2d inside. The manhole main body 2 is an example of the main body. The manhole main body 2 is formed of, for example, a reinforcing bar concrete.

  The manhole neck 3 is formed in a hollow cylindrical shape, and is fixed to the upper portion of the manhole main body 2 by a neck hole 2a. The cavity inside the manhole neck 3 and the hole 2a for the neck are formed in the same cross-sectional shape, and the upper part of the manhole neck 3 and the inside of the manhole main body 2 communicate with each other through the inside of the manhole neck 3. The cavity inside the manhole neck 3 is defined as a manhole entrance 5.

  The manhole neck 3 is an example of the neck. The manhole neck 3 is formed of, for example, a reinforcing bar concrete.

  The cable entry slit portion 4 is formed to have a slit communicating from the upper part to the lower part. The slit of the cable entry slit 4 is formed to have a width that is at least larger than the thickness of the cable.

  The cable entry slit 4 is connected to the manhole neck 3 at the slit hole 2b and fixed to the upper part of the manhole body 2. The slit of the cable entry slit 4 and the slit hole 2b are formed in the same cross-sectional shape, and the upper part of the cable entry slit 4 and the inside of the manhole body 2 are the same as those of the cable entry slit 4. It communicates through a slit.

  In addition, a cutout having the same width as that of the slit of the cable entry slit 4 is provided from the upper part to the lower part at the connecting part between the manhole neck 3 and the two cable entry slits 4. Due to this notch, the manhole entrance 5 of the manhole neck 3 and the slit of the cable entry slit 4 communicate from the top to the bottom.

  Further, the lengths of the manhole entrance 5 and the cable entry slit 4 shown by the arrow d in FIG. 2 are formed to be longer than the allowable bending diameter of the cable to be accommodated.

  The cable entry slit portion 4 is an example of a cable entry portion. The cable entry slit portion 4 is formed of, for example, a reinforcing bar concrete.

  Further, as indicated by an arrow a in FIG. 1, a manhole cover 6 can be opened and closed at the upper end of the manhole neck 3. Further, as shown by arrows b and c in FIG. 1, a slit cover 7 can be freely opened and closed at the upper end of the cable entry slit 4.

  The manhole cover 6 and the slit cover 7 can block the manhole entrance 5 and the cable entry slit 4. The slit cover 7 is an example of a cable entry cover.

  Further, as shown in FIGS. 1 to 3, a pipe line 8 is connected to each pipe hole 2 c of the manhole body 2. Each cable 9 is laid in the pipe line 8. The laid cable 9 is placed in the manhole main body 2 by the cable installation tool 2d.

  Further, in the manhole 1 described with reference to FIGS. 1 to 3, the manhole main body 2 includes two pipe attachment holes 2 c and two pipes 8 are connected to each other. 9 was accommodated. However, the manhole main body 2 is provided with three or more pipe attachment portions 2c and three or more pipes 8 are connected, and the cables 9 are accommodated in the respective pipes 8 via the manhole main body 2 inside. It is good also as a structure to be performed.

<Example of cable laying method in manhole of this embodiment>
Next, the method of inserting the cable 9 into the manhole 1 described with reference to FIG. 1 will be described as an embodiment of the cable laying method.

  4 to 8 are explanatory views of a method of inserting the cable 9 into each pipe line 8 from the manhole entrance 5 and the cable entry slit 4 of the manhole 1, and a cross section taken along the line AA in FIG. Show. 4 to 8, the cable 9 and the cable drum 11 are not cut.

  In the following description, it is assumed that the manhole B50b shown in FIG. 13 is the manhole 1 of the present embodiment, and the cable 9 is inserted from the manhole B50b to the utility pole A32 and the utility pole B33. In FIG. 4 to FIG. 8, it is assumed that the pipe line 8a is a pipe line going to the electric pole A32, and the pipe line 8b is a pipe line going to the electric pole B33.

  In the manhole 1, the cable 9 enters the pipe 8 as follows. First, the manhole cover 6 and the slit cover 7 are opened.

  Thereafter, as shown in FIG. 4, the cable 9 is pulled out from the cable drum 11 from the cable front end A 9 a side, and is inserted into the manhole main body 2 from the manhole inlet 5 of the manhole 1 and the cable entry slit 4. When the cable 9 is inserted into the manhole entrance 5 and the cable entry slit 4, the cable 9 is protected while being protected by a cylindrical protective tube 12 to prevent damage to the cable 9. The protective tube 12 has, for example, a half structure, and can be removed after work.

  The cable front end portion A9a is an end portion that enters the power pole A32 side. After the cable tip A9a is inserted into the manhole body 2, the cable tip A9a is inserted into the conduit 8a on the utility pole A32 side as shown by the arrow e in FIG. 4, and the cable 9 is inserted to the utility pole A32.

  After the cable 9 is inserted to the utility pole A32, as shown in FIG. 5, all the cables 9 are pulled out from the cable drum 11 to secure the cable front end B9b. The cable tip B9b is the end that is inserted into the utility pole B33.

  Thereafter, as shown in FIG. 6, the cable tip B 9 b is inserted into the manhole main body 2 from the manhole entrance 5 and the cable entry slit 4 while being protected by the protection tube 12. After the cable tip B9b is inserted into the manhole main body 2, the cable tip B9b is inserted into the conduit 8b on the utility pole B33 side as shown by the arrow f in FIG. 6, and the cable 9 is inserted to the utility pole B33.

  FIG. 7 is an explanatory diagram showing a state in which the last portion of the cable 9 is put into the manhole 1. When the last portion of the cable 9 remaining on the ground is put into the manhole 1, the cable 9 is bent into a semicircular shape.

  The manhole 1 is formed in a shape in which the lengths of the manhole entry hole 5 and the cable entry slit 4 shown by the arrow d in FIG. 2 are longer than the allowable bending diameter of the cable 9 to be accommodated. For this reason, unlike the conventional manhole 50 which does not include the cable entry slit portion 4 described with reference to FIGS. 14 to 16, it is possible to enter the cable 9 having a larger allowable bending diameter.

  FIG. 8 is an explanatory view showing a state where all the cables 9 are put in the manhole 1. After all the cables 9 are placed in the manhole 1, the cables 9 are installed on the cable installation tool 2d in the manhole main body 2 as shown in FIGS.

  After the cable 9 is installed on the cable installation tool 2d in the manhole body 2, the manhole cover 6 and the slit cover 7 are closed.

  In the manhole 1 according to the present invention, the manhole entrance 5 and the cable entry slit 4 have a length longer than at least the allowable bending diameter of the cable 9 to be accommodated. For this reason, the cable 9 is formed in a semicircular shape by the cable laying method of the present invention in which the cable 9 is inserted into one conduit 8 from one end and then the cable 9 is inserted into the other conduit 8 from the other end. The last part of the cable 9 can be inserted into the manhole body 2.

  Thereby, it becomes possible to lay the cable 9 from the manhole 1 in the middle of the cable laying path without providing a connection point.

  FIG. 9 is an explanatory diagram when the cable laying method of the present invention is used in a conventional manhole 50. The diameter of the manhole entrance of the manhole currently used is about 600 mm to 850 mm. On the other hand, the allowable bending diameter of power cables currently used is about 850 mm to 1500 mm.

  For this reason, when the cable laying method of the present invention is used in the conventional manhole 50, the allowable bending diameter of the cable 9 indicated by the arrow h becomes larger than the diameter of the manhole entrance 55 shown by the arrow i. It cannot be placed inside the manhole body 52.

  Further, if the diameter of the manhole entrance 55 is increased in order to enter a cable having a large allowable bending diameter, a manhole cover having a large diameter is required. A manhole cover with a large diameter has a problem that the weight increases and it is difficult to open and close the manhole cover during operation. Further, the manhole cover having a large diameter has problems such as high cost and a cause of slipping of an automobile or the like.

  For this reason, in the conventional manhole 50, it is necessary to lay the cable 9 by a method in which different cables 9 are inserted into the two pipe lines 8 and the two cables 9 are connected in the manhole 50.

  In the manhole 1 and the cable laying method of the present embodiment, unlike the conventional manhole 50, there is no need to adopt a method of laying a cable to be connected in the middle of the pipe. For this reason, problems such as an increase in construction time and necessary materials, generation of a space for accommodating the extra length of the cable, and an increase in accident factors at the cable connection location after the operation of the facility do not occur.

  Moreover, according to the manhole 1 of this Embodiment, since the manhole cover 6 and the slit part cover 7 are formed separately, the general-purpose thing generally used as the manhole cover 6 should be used. it can. Furthermore, the manhole cover 6 and the slit part cover 7 can each be comprised lightweight.

  Furthermore, according to the manhole 1 of the present embodiment, since the manhole entrance 5 and the cable entry slit 4 are formed integrally, the space above the manhole body 2 can be used efficiently. .

<Configuration example of manhole of other embodiment>
Next, a configuration example of the manhole 1 according to another embodiment will be described. FIGS. 10 to 12 are plan views showing states of the manhole 1 according to another embodiment as viewed from above. 10 to 12, the manhole cover 6 and the slit portion 7 are not shown.

  In the manhole 1 according to another embodiment shown in FIGS. 10 to 12, the manhole body 2, the manhole neck 3, the cable entry slit 4, and the manhole cover are the same as the manhole 1 described with reference to FIGS. 6 and a slit lid 7.

  FIG. 10 shows an example in which a cable entry slit 4 is provided separately from the manhole entry 5. By increasing the length of the cable entry slit portion 4 indicated by the arrow j, the cable 9 having a large allowable bending diameter can be inserted by the method described with reference to FIGS.

  In the manhole 1 shown in FIG. 10, since the manhole neck 3 and the cable entry slit 4 are separately provided, the manhole neck 3 and the manhole cover 6 are generally used. Can be used.

  FIG. 11 shows an example in which the cable entry slit 4 is provided only on one side of the manhole entry 5. By increasing the lengths of the manhole entrance 5 and the cable entry slit 4 shown by the arrow k, the cable 9 having a large allowable bending diameter can be inserted by the method described with reference to FIGS. become.

  The manhole 1 shown in FIG. 11 has a space for forming the cable entry slit 4 only in one direction because the manhole neck 3 is formed near the upper corner of the manhole body 2. Applicable where possible.

  Moreover, according to the manhole 1 shown in FIG. 11, since the manhole entrance 5 and the cable entry slit 4 are integrally formed, the space above the manhole body 2 can be used efficiently.

  FIG. 12 shows an example in which a cable entry slit 4 is provided between two manhole entrances 5. By increasing the lengths of the manhole entrance 5 and the cable entry slit 4 shown by the arrow l, it is possible to insert the cable 9 having a large allowable bending diameter by the method described with reference to FIGS. become.

  The manhole 1 shown in FIG. 12 is applicable when a plurality of manhole neck portions 3 are formed on the upper portion of the manhole body portion 2.

  Moreover, according to the manhole 1 shown in FIG. 12, since the manhole entrance 5 and the cable entry slit 4 are integrally formed, the space above the manhole body 2 can be used efficiently.

  The present invention is applied to a manhole embedded in the ground and connected to a plurality of conduits that accommodate cables in the ground.

It is explanatory drawing which shows the example of the manhole of this Embodiment. It is explanatory drawing which shows the example of the manhole of this Embodiment. It is explanatory drawing which shows the example of the manhole of this Embodiment. It is explanatory drawing which shows the example of the laying method of the cable in the manhole of this Embodiment. It is explanatory drawing which shows the example of the laying method of the cable in the manhole of this Embodiment. It is explanatory drawing which shows the example of the laying method of the cable in the manhole of this Embodiment. It is explanatory drawing which shows the example of the laying method of the cable in the manhole of this Embodiment. It is explanatory drawing which shows the example of the laying method of the cable in the manhole of this Embodiment. It is explanatory drawing which shows the example of the laying method of the cable in the conventional manhole. It is explanatory drawing which shows the example of the manhole of other embodiment. It is explanatory drawing which shows the example of the manhole of other embodiment. It is explanatory drawing which shows the example of the manhole of other embodiment. It is explanatory drawing which shows the example of installation of a pipe line and a manhole. It is explanatory drawing which shows the structure of the conventional manhole. It is explanatory drawing which shows the structure of the conventional manhole. It is explanatory drawing which shows the structure of the conventional manhole.

Explanation of symbols

1 Manhole 2 Manhole body 3 Manhole neck 4 Cable entry slit 5 Manhole entry 6 Manhole cover 7 Slit cover

Claims (6)

In a manhole structure in which a plurality of pipelines for accommodating cables are connected and buried in the ground together with the pipelines,
A main body part that is formed in a hollow box-like shape, is located in the ground, and a plurality of the pipe lines are connected;
A cable entry line located at the top of the main body,
With a cable entry line lid,
The cable insertion part has a shape in which one width is longer than the diameter of the cable to be accommodated and the other width is longer than an allowable bending diameter of the cable, and a hollow part communicating the upper part of the ground and the inside of the main body is formed. Have
The cable entry line cover covers the cavity of the cable entry part so as to be openable and closable. A cylindrical neck located at the top of the main body,
The upper part of the ground is communicated with the inside of the main body part in the hollow part inside the neck part,
The cavity part of the cable entry part and the cavity part of the neck part are communicated from the upper surface of the ground to the upper surface of the main body part with a width larger than the diameter of the cable,
2. The manhole structure according to claim 1, wherein a length of the cavity portion of the cable insertion portion and the cavity portion of the neck portion that are communicated is longer than an allowable bending diameter of the cable. A neck lid that covers the cavity of the neck so as to be freely opened and closed;
The manhole structure according to claim 2, wherein the cable entry line cover and the neck cover are formed separately. In a cable laying method in which a plurality of pipelines in which cables are accommodated are connected, and from the manhole embedded in the ground together with the pipelines, the cables are inserted into the pipelines.
From the top of the ground, put one end of the cable into the manhole,
Enter the cable from one end side of the cable put into the manhole into one of the pipes to be connected,
From the top of the ground, put the other end of the cable into the manhole,
A cable laying method, wherein the cable is inserted from the other end side of the cable inserted into the manhole into the other conduit to be connected. The cable laying method according to claim 4, wherein the cable is inserted into the manhole from a hole having a width longer than an allowable bending diameter of the cable to be inserted. 6. The cable according to claim 4, wherein the cable is inserted into a route for laying the cable from two pipe lines connected to a manhole provided in the middle of the route for laying the cable. Cable laying method.

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