JP2920111B2 - Connection structure of common groove for underground cable installation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connection structure of a common groove used when installing cables for power, communication, etc. underground.

[0002]

2. Description of the Related Art In recent years, means for laying cables for electric power, communication, etc. underground has been adopted in order to improve the scenery of cities and urban areas. A box-shaped concrete product, a flexible tube made of resin or a porous tube made of concrete or porcelain is used as a member for constructing the conduit for accommodating the cable. In this case, since the weight of the vehicle also reaches the pipeline, the product performance such as the strength of the pipeline, flatness (there is hardly any distortion in the pipeline), and durability is important.

As described above, in the case of a pipe installed in a place where a vertical load is applied by a vehicle or the like, even if the pipe is made of resin having a relatively small structural strength, concrete is cast after the installation to improve the strength. Although there is a means to achieve this, it is preferable to use a concrete or ceramic perforated tube in view of simplicity of construction and construction costs.

[0004] In the case of a concrete perforated pipe, in order to protect the cable from sewage or the like, a product or construction method to which a socket-shaped connection structure or packing maintaining water tightness is sufficiently applied. However, pipes to be installed underground are more resistant to vibrations caused by earthquakes and shocks caused by uneven sedimentation. In order to achieve this, the workability must be pursued.

[0005] In consideration of both durability and workability with respect to an excessive load or a long-term load, for example, a prefabricated pipe made of a connecting rod as in the invention disclosed in Japanese Patent Publication No. 60-10235 is disclosed. There is a connection method.

[0006]

However, the aforementioned Japanese Patent Publication No. Sho 6
In the case where the common grooves are firmly connected by the means disclosed in Japanese Patent Application Laid-Open No. 0-10235, when connecting the common grooves, screw rods required for pushing and fitting, and connecting bolts for maintaining the fastened state. It is necessary to use the two methods described above, and there is also trouble during construction such as replacement with an insertion hole after connection, and there is room for improvement in workability.

In a conventional joint groove having a socket structure, the watertightness of the connection portion is ensured by the fitting structure of the male portion and the female portion and the installation of rubber packing in close contact with the joint peripheral surface. However, the joint surfaces are not directly and mutually bonded, and if the connection tool becomes loose or loose due to vibration or load, the adhesion of the packing will be lost, and groundwater or There is a possibility that a foreign matter or the like may enter and damage the cable installed in the pipeline.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned conventional problems, and has a small number of construction steps and can maintain the water stopping property of a connecting portion for a long period of time. The gist of the invention is to provide bolt insertion holes and cable insertion holes, respectively, with a cylindrical collar around one end and a collar at the other end. A joint groove having a male portion fitted in the fitting portion of the cylindrical collar, wherein a pair of packings in which the fitting portion and the male portion fitted inside the fitting portion are disposed apart from each other back and forth. And the two joint grooves are integrally connected by fastening a connecting rod that can be connected by a screw connection inserted into the bolt insertion hole, and one end opening of the bolt insertion hole is a funnel-shaped hole. And the connecting rod has a male screw at the tip. And an enlarged head having a cross section substantially the same shape as the opening of the one end, and a female screw screwed with the male screw in a center hole extending from the enlarged head. In the connection structure of the groove.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. In FIGS. 1 and 2, A is a common channel for installing underground cables, and the common channel A is
It is constructed by connecting box-shaped common grooves 1 and 1-1 formed of concrete as shown in FIGS. 3 and 4. That is, the common groove 1 has a solid rectangular parallelepiped shape, and a bolt insertion hole 2 penetrates the center thereof along the longitudinal direction, and the one end opening 3 of the bolt insertion hole 2 is formed.
Is a funnel-shaped hole in which a large-diameter port and a small-diameter port having substantially the same cross section as the outer shape of the enlarged head of the connecting rod described later are continuously provided on the inclined peripheral surface 3A.

Reference numeral 4 denotes a plurality of cable insertion holes formed around the bolt insertion hole 2 and having different diameters. Each cable insertion hole 4 extends in parallel with the bolt insertion hole 2 and penetrates the common groove 1. Each cable insertion hole 4 is provided with a pipe 5 made of vinyl chloride. This is because when a heavy cable is inserted into the cable insertion hole 4, the frictional resistance with the inner peripheral surface of the cable insertion hole 4 is reduced to facilitate the insertion.

Reference numeral 6 denotes a rectangular cylindrical collar formed of metal. One end 6A of the collar is embedded in the outer periphery of one end of the common groove 1 through a packing 7 as shown in FIGS. The other end extends outward from one end face 1A of the common groove 1 to form a fitting portion 6B, and the male portion 1B formed at the other end of the common groove 1 in the fitting portion 6B. Is formed so as to be fitted.

Reference numeral 8 denotes a fixed packing having a substantially right-angled triangular cross section.
B, and is fixed to the inner periphery of the base, and the slope 8A of the fixed packing 8 is oriented in a direction facing the opening of the fitting portion 6B.
That is, one end face 1 of the common groove 1 extends from the inner peripheral face of the cylindrical collar 6.
It is installed in a state of gradually descending toward A. In the drawing, 9A is a pipe for injecting a sealing material attached to the lower part of the cylindrical collar 6 in a penetrating state, and 9B is a pipe for removing air attached to the upper part.

Reference numeral 10 denotes a connecting rod inserted into the bolt insertion hole 2. As shown in FIG. 5, a male screw 11 is formed on the outer periphery of the tip, and the other end is continuous with a tapered peripheral surface 12A. A dish-shaped enlarged head 12 is provided.
A female screw 13 to be screwed with the male screw 11 is formed on the inner periphery of a central hole 12C extending in the axial direction following the large-diameter hole 12B formed at the center of 2. In the figure, reference numeral 14 denotes a recess formed on the end face of the enlarged head 12 for engagement with a rotating tool described later.

Reference numeral 15 denotes a rotary tool for rotating the connecting rod 10, as shown in FIG.
6, a rotation shaft 17 fixed to the center of one end surface of the rotation support portion 16, a grip portion 18 fixed to one end of the rotation shaft 17 in a T-shape, and the protrusion protruding from the other end surface of the rotation support portion 16. Each is composed of an engaging projection 19 that engages with the locking recess 14.

Next, a method of forming the common groove A by connecting the common grooves 1 in series will be described in detail. As shown in FIG. 7, first, the common groove 1-1 to be connected is already laid. When the male part 1B of the common groove 1-1 is brought close to the fitting part 6B of the cylindrical collar 6 of the common groove 1 where the above is completed, the joint groove 1-B is inserted into the fitting part 6B. 1 male part 1B is loosely fitted. At this time, the packing 20 is fitted in advance on the outer periphery of the base of the male portion 1B of the common groove 1-1.

Then, the connecting rod 10 is inserted into the bolt insertion hole 2 of the joint groove 1-1 to be connected from the opening 3 through the opening 3, and the male screw 11 formed at the tip of the connecting rod 10 is The connecting rod 10 is inserted into the center hole 12C following the large-diameter hole 12B of the enlarged head 12 of the connecting rod 10 fastened in the bolt insertion hole 2 of the existing common groove 1. And the inserted connecting rod 1
0 at its enlarged head 12 so that the center hole 1
The male screw 11 of the inserted connecting rod 10 is screwed into the female screw 13 formed in 2C.

In this state, as shown in FIG. 6, the rotating tool 15 is provided with the respective engaging projections 19 provided on the other end face of the rotary support portion 16 and the end face of the enlarged head 12 of the inserted connecting rod 10. And each of the engaging projections 19 is engaged with the engaging recess 14. When the rotating shaft 17 is turned by the grip portion 18 while supporting the rotation support portion 16 with one hand, the connecting rod 10 is screwed in the direction of the existing common groove 1 by screwing the male screw 11 and the female screw 13, The tapered peripheral surface 12A of the enlarged head 12 abuts against the inclined peripheral surface 3A in the opening 3 of the common groove 1-1.

Further, the rotating shaft 1 is
When the connecting rod 10 is screwed into the bolt insertion hole 2, the tapered peripheral surface 12 </ b> A of the enlarged head 12 is
The inclined peripheral surface 3 </ b> A of the opening 3 is pressed in the direction of the common groove 1. In this case, the enlarged head 12 and the opening 3 of the common groove 1-1 abut on the tapered peripheral surface 12A and the inclined peripheral surface 3A. The pressing force in the direction of 1 is easily transmitted to the common groove 1-1, and the male portion 1B of the common groove 1-1 moves in the direction of the arrow in FIG.

Thus, as shown in FIG.
The end of the male part 1B abuts on the slope part 8A of the fixed packing 8, but as the male part 1B further enters the deep part of the fitting part 6B, the outer peripheral surface thereof becomes the slope part 8 of the fixed packing 8.
A is pressed in the direction of the inner peripheral surface of the cylindrical collar 6, and the male part 1B is fitted into the fitting part 6B with the fixed packing 8 crushed. At the same time, the tip of the fitting portion 6B presses down the packing 20 fitted on the outer periphery of the base of the male portion 1B, and the joint groove 1-1 and the existing joint groove 1 are fixed to each other as shown in FIG. And when they are connected in a sealed state via the packing 20,
As shown in FIG. 11, the existing common groove 1 and the common groove 1-1 are integrally connected by a connecting rod 10.

As described above, the common groove 1-1 and the existing common groove 1 are rigidly connected to each other in a watertight and integral structure. In the present invention, the watertight structure is further improved by the following structure. Can be improved. That is, as shown in FIG. 9, the space 2 surrounded by the outer periphery of the fixed packing 8, the packing 20, and the male part 1B in the fitting part 6B.
The sealing material 21 is injected into the inside of the cylindrical collar 6 from the seal injection pipe 9A attached to the lower part of the cylindrical collar 6, and the injection work is continued until the seal material 21 overflows from the air release pipe 9B attached to the upper part. The space 22 is filled with the sealing material 21.

When the sealing material 21 is cured, as shown in FIG. 10, the joint groove 1-1 to be connected to the joint groove 1 is connected to the fitting portion 6B of the cylindrical collar 6.
, Fixed packing 8, packing 20, sealing material 2
1 provides a connection structure that is more tightly bonded over a wider area, and that is durable against vibration and load with water tightness. Here, it is desirable that the sealing material 21 has physical properties (fluidity during construction, strength after hardening, adhesive strength) similar to mortar, grout material, etc. having high fluidity.

Similarly, the next common groove 1-2 is connected to the connected common groove 1-1, and this operation is repeated to obtain a desired length as shown in FIGS. 1, 2 and 12. Is formed. By inserting cables into the respective cable insertion holes 4 communicating with the common channel A, cables for power and communication are installed underground.

In FIGS. 1 and 2, reference numeral 23 denotes a single pipe portion which is constituted by a flexible pipe 24, and a plurality of cables K coming out of the cable insertion holes 4 of the common groove 1 are individually drawn out. Part. As shown in FIG. 13, the connecting means between the single pipe portion 23 and the common groove 1 is formed by a protruding portion 5 </ b> A of the synthetic resin pipe 5 installed in each cable insertion hole 4 and one end of the flexible pipe 24. Are connected via both receiving sockets 25, and watertightness and durability can be ensured by a simple structure.

In the drawing, reference numeral 26 denotes a branch box for branching cables in the branch box 26, pulling out the branched cables from the branch box 26 and installing them at required places. As shown in FIG. 14, the connection means between the other end of the flexible tube 24 and the branch box 26 forms a through hole 27 in a side wall 26A of the branch box 26, and a mortar 28 or the like 28 in the through hole 27. Bell-mouth-shaped opening 29 of connecting pipe 29 fixed through
A is connected by fitting the other end of the flexible pipe 24 into A, thereby improving construction efficiency and water tightness.

[0025]

As described above, the connecting structure of the common groove for installing underground cables according to the present invention has a structure in which a bolt insertion hole and a cable insertion hole are respectively provided, and a cylindrical collar is provided on the outer periphery of one end. Is a common groove provided with a male part fitted into the fitting part of the cylindrical collar at the other end, wherein the fitting part and the male part fitted inside the fitting part are separated from each other back and forth. The joint groove is connected via a pair of packings provided, and the joint groove is integrally connected by fastening a connection rod which can be connected by screw connection inserted into the bolt insertion hole. The opening has a funnel-like hole shape, and the connecting rod has a male screw at the tip and an enlarged head having the same shape as the one end opening at the other end, and a central hole extending from the enlarged head. It has a structure that has a female screw that engages with a male screw. Et al., The robust integration of joint grooves between by smoothly when it is possible to perform ゝ monitor, fastening of the connecting rod with a relatively small force coupling operation by connecting rod joint groove between,
A watertight connection structure with packing due to integration.
Moreover, since the fitting portion and the male portion fitted inside thereof are connected via a pair of packings disposed apart from each other, even if the connecting portion is bent due to uneven settlement of the ground or the like. The water stopping performance does not deteriorate. In addition, the fixing packing has a substantially right-angled triangular cross section, and the inclined surface thereof is installed in a direction facing the opening of the fitting portion. Can be performed at the same time, thus reducing the number of working steps. In addition, since the space between the pair of packings is filled with the sealing material, various effects such as a connection structure that is durable against vibration and load as well as watertight due to the adhesive effect of the sealing material are obtained. is there.

[Brief description of the drawings]

FIG. 1 is a front view of a laid state of a common channel to which a connection structure according to the present invention is applied.

FIG. 2 is a plan view of FIG.

FIG. 3 is a partially omitted front view of a common groove.

FIG. 4 is a right side view of FIG. 3;

FIG. 5 is a partially omitted perspective view of a connecting rod.

FIG. 6 is a perspective view of a rotary tool.

FIG. 7 is an enlarged cross-sectional first operation explanatory view of a connecting portion.

FIG. 8 is an enlarged sectional explanatory view of a second operation of the connecting portion.

FIG. 9 is an explanatory view of a third operation of the connecting portion.

FIG. 10 is an explanatory diagram of a fourth operation of the connecting portion.

11 is an enlarged partial cross-sectional view taken along the line II-II of FIG. 1;

12 is an enlarged partial cross-sectional view taken along the line III-III of FIG. 2;

FIG. 13 is an enlarged partial cross-sectional view taken along the line IV-IV of FIG. 2;

FIG. 14 is an enlarged partial cross-sectional view taken along line VV of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Joint groove 1A End surface 1B Male part 2 Bolt insertion hole 3 Opening 3A Inclined peripheral surface 4 Cable insertion hole 6 Cylindrical collar 6A One end 6B Fitting part 8 Fixed packing 8A Slope 10 Connecting rod 11 Male screw 12 Enlarged head 12C Center hole 13 Female screw 20 Packing 21 Sealing material 22 Space

Claims (4)

(57) [Claims] The present invention is characterized in that when a bolt insertion hole and a cable insertion hole are respectively penetrated, a cylindrical collar is fitted around the outer periphery at one end and a fitting portion is fitted into a fitting portion of the cylindrical collar at the other end. A joint groove provided with a portion, wherein the fitting portion and the male portion fitted inside the fitting portion are connected via a pair of packings arranged at a distance from each other and inserted into the bolt insertion hole. The joint groove is integrally connected by fastening a connecting rod that can be connected by screw connection, one end opening of the bolt insertion hole has a funnel-shaped hole shape, and the connecting rod has a male screw at the tip. An underground cable installation, comprising: an enlarged head having a cross section substantially the same shape as the one end opening at each end, and a female screw screwed into the male screw in a center hole extending from the enlarged head. Connection structure of common groove. 2. The joint for underground cable installation according to claim 1, wherein the pair of packings are a fixed packing fixed to the inner periphery of the base of the fitting portion and a packing fitted to the outer periphery of the base of the male portion. Groove connection structure. 3. The underground cable according to claim 1, wherein the fixed packing has a substantially right-angled triangular cross section, and the slope portion is installed in a direction facing the opening of the fitting portion. Connection structure of common groove for installation. 4. The underground cable connecting joint groove connecting structure according to claim 1, wherein the space between the pair of packings is filled with a sealing material.