JP2003244814A - Conduit rodding method in cable conduit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conduit rodding method which can insert a wire for pulling another cable into a conduit, in which a cable has already been laid, quickly by a method wherein a pulling force of a pulling device which inserts the wire is increased and, at the same time, the adhesion of the pulling device to the already laid cable is avoided. <P>SOLUTION: A pulling device 1 comprises a pulling member 2 having a parachute-shape, a pulling guide member 3 which is provided on the lower surface side of the pulling member 2, deformable and restorable, and formed into an approximately flat curved surface unit, and a bundle part 5 composed of pulling strings 4 which are connected with the pulling member 2 and the pulling guide member 3 and bundled together. A wire 6 is connected with the bundle part 5 of the pulling strings 4 of the pulling device 1 and the pulling device 1 is inserted into the cable conduit 7 and sucked or pressure-transferred to insert the wire 6 into the cable conduit 7. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-pipe line construction method for a cable laying pipe, and more particularly, to increase the traction force of a traction tool for inserting a wire rod for further drawing a cable into a pipe line of the cable laying pipe. The present invention relates to a pipe running method in which a wire rod is quickly inserted into a pipeline of a cable laying pipe by achieving both prevention of suction of a pulling tool to the laying cable side.

[0002]

2. Description of the Related Art In recent years, in order to improve the aesthetics of cities,
The movement of cables such as telephone wires laid on the ground into pipes buried underground is being promoted, and various construction methods have been proposed as methods for inserting cables into pipes. The conventional method is to lay a cable in the pipeline by inserting the wire into the pipeline buried underground, connecting the cable to the wire inserted in the pipeline and pulling the wire. However, the same construction method is commonly used when further laying a cable in the conduit of the cable laying pipe in which the cable has already been laid.

Referring to FIG. 3, as a preliminary construction method for further laying a cable in the above-mentioned conventional cable laying pipe, a pipe running method in which a wire is previously inserted into the pipe laying path of the cable laying pipe will be described with reference to FIG. Explaining this, the tow cords c provided on the parachute-shaped tow member b are bundled to form the tow tool a, and the cable f is laid to the tow tool a in which the wire rod e is connected to the focusing portion d of the tow cord c. The wire e is inserted into the conduit of the cable laying pipe g by inserting it into the conduit of the cable laying pipe g and sucking or pumping the pulling tool a by a suction device or a blower.

[0004]

However, in the conventional in-pipe line construction method in which the wire rod is previously inserted into the conduit of the cable laying pipe described above, the pulling cord c provided on the parachute-like pulling member b is bundled. Since the pulling tool a is configured by inserting the pulling tool a into which the wire rod e is connected to the focusing portion d of the pulling string c, the pulling tool a is inserted into the conduit of the cable laying pipe g and pulled by the suction device or the blower. When the tool a is sucked or pressure-fed, the parachute-shaped traction member b moves by receiving the air flow h flowing in a wide space above the cable laying pipe g, but the traction member b in the pipe line. Negative pressure Venturi effect due to the air flow h ′ flowing in the narrow space in which the cable f below is laid,
The parachute-shaped traction member b receives a suction action to the cable f side, and not only the friction with respect to the cable f increases but the traction force is reduced, but the meandering of the cable f further increases the suction action to the cable f side. In this case, as shown in FIG. 4, the parachute-shaped traction member b is connected to the cable f.
There was a problem that it was adsorbed on the side and the traction function was lost.

The parachute-shaped traction member b is adsorbed to the cable f side by the negative pressure Venturi effect by the air flow h'flowing through the narrow space in which the cable f below the traction member b is laid in the above-mentioned pipeline. In order to avoid the situation, it is conceivable that the pulling member is made of a material that is hard to be adsorbed, for example, a sponge. However, when the pulling member is made of only a sponge, the pulling member is adsorbed to the cable f side. However, it is difficult to form the pulling member composed only of the sponge into the cross-sectional shape of the wide space above the inside of the conduit of the cable laying pipe g, and it is deformed by the meandering of the cable f. It is difficult to follow the cross-sectional shape of the wide area,
Moreover, since the closeness to the inner wall of the conduit in the wide area is slower than that of the parachute-shaped traction member b, the traction member constituted only by the sponge has a problem that the wind pressure effect is reduced and the traction force is reduced as a whole. Is invited.

The present invention has been invented to solve these problems, and increases the pulling force of a pulling tool for inserting a wire rod for further pulling a cable into a conduit of a cable laying pipe, and It is an object of the present invention to provide an in-pipe passage construction method in which a wire rod is quickly inserted into a conduit of a cable laying pipe by achieving both compatibility with prevention of attraction of a pulling tool to the cable side.

[0007]

In order to achieve the above-mentioned object, the invention according to claim 1 is an in-pipe passage construction method in which a wire rod for further drawing the cable is inserted into a pipe passage in which the cable is laid. And a towing member formed in a parachute shape, a towing guide member disposed on the lower surface side of the towing member and formed into a deformable and restorative flat flat curved body, the towing member and the towing member. A towing tool is configured by a focusing portion that bundles the tow cords provided on the guide member, and the tow tool in which a wire rod is connected to the focusing portion of the tow cord is inserted into the conduit of the cable laying pipe for suction or pressure feeding. As a result, the wire rod is inserted into the conduit of the cable laying pipe.

According to the invention of claim 1,
A tow member formed in a parachute shape, a tow guide member that is disposed on the lower surface side of the tow member, and is formed into a deformable and restorative flat flat curved body, and the tow member and tow guide member. It is configured by a converging unit that consolidates the tow cord provided on the, so that a pulling tool in which a wire rod is connected to the converging unit of the tow cord is inserted into the conduit of the cable laying pipe, and the suction device or When the tractor is sucked or pressure-fed by the air blower, the tractor receives the air current flowing in the wide area above the pipe line of the cable laying pipe and moves to move the wire rod into the pipe line of the cable laying pipe. Can be inserted.

In particular, when the tow tool moves by receiving the airflow flowing in the wide space above in the conduit of the cable laying pipe, the tow member formed in the parachute shape of the tow tool has the above-mentioned wide space. Due to the wind pressure effect of the airflow flowing through the pipe, it easily fits into the inner wall side of the pipeline in the wide area, and since the close contact with the inner wall of the pipeline in the wide area is good, the traction force of the tractor due to the wind pressure effect can be increased.

At the same time, the traction guide member of the traction device is
The negative pressure Venturi effect due to the airflow flowing through the narrow space where the cable on the lower side of the tow tool is laid, that is, the suction action to the cable side is received, but the tow guide member is deformable and has a restoring property. Since it is formed into a flat curved surface body, it is difficult to adapt to the cable side of the wide area due to the wind pressure effect of the airflow flowing in the wide area, and the close contact with the cable in the wide area is slow, so It is possible to prevent the pulling device from being attracted to the cable side due to the negative pressure Venturi effect, and moreover, the pulling force of the pulling device due to the wind pressure effect can be increased by the amount that the pulling guide member is hardly affected by the negative pressure venturi effect. it can.

According to a second aspect of the present invention, in the first aspect of the present invention, the traction guide member formed on the slightly flat curved body is covered with a net formed in a net shape.

According to the second aspect of the present invention, since the traction guide member formed on the curved body is covered with the net formed in the mesh shape, the surface of the traction guide member formed of the curved body is formed in the mesh shape. Due to the wind pressure effect of the air current flowing in the upper wide area in the conduit of the cable laying pipe, it is more difficult to adapt to the cable side of the wide area, and the closeness to the cable in the wide area is more Since it becomes slow, it is possible to prevent suction of the pulling tool to the cable side due to the negative pressure Venturi effect.

According to a third aspect of the invention, in the first aspect of the invention, the parachute-shaped traction member is biased rearward with respect to the traction guide member.

According to the third aspect of the invention, since the parachute-shaped traction member is biased rearward with respect to the traction guide member, it is moved by the wind pressure effect of the airflow flowing in the wide area. The parachute-shaped traction member can maintain the wind pressure effect due to the air flow even when the leading traction guide member is stagnant in the narrow area when the pulling tool that passes through the narrow area due to the meandering of the cable. Therefore, the traction guide member is pushed backward, and the movement of the traction guide member can be assisted when the traction guide member passes through the narrow region.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described with reference to an embodiment shown in the drawings. FIG. 1 is a partial vertical cross-sectional side view of a pipe laying method for a cable laying pipe of the present invention, and FIG. 2 is a vertical cross-sectional rear view of line AA in FIG. First, the configuration of the pulling tool used in the conduit running method in the cable laying pipe of the present invention will be described based on FIG. 1 with reference to FIG. 2. The main configuration of the pulling tool 1 is formed in a parachute shape. Traction member 2
And a traction guide member 3 which is disposed on the lower surface side of the traction member 2 and is formed into a deformable and resiliently curved flat flat body.
And a focusing portion 5 that focuses the tow cord 4 provided on the tow member 2 and the tow guide member 3, and the in-pipe line construction method for the cable laying pipe 7 performed by using the tow tool 1 is the tow cord. The pulling tool 1 in which the wire rod 6 is connected to the focusing portion 5 of the cable 4 is inserted into the conduit of the cable laying pipe 7, and the pulling tool 1 is sucked or pressure-fed by a suction device or an air blower (not shown). The wire rod 6 is inserted into the conduit of the cable laying pipe 7 by receiving and moving the airflow 9 flowing in the wide space above in the conduit of the laying pipe 7.

Next, the concrete construction of the pulling tool 1 will be described in more detail, and an embodiment of the in-pipe passage construction method for the cable laying pipe 7 will be described together. The parachute-shaped traction member 2 is made of various plastic or rubber films or sheets, or cloth made by knitting various fibers, as long as it has a flexible wind receiving effect. Although not shown in the drawing, the bundling portion 5 that bundles the tow cords 4 may be provided with a connecting ring for connecting the wire rod 6 for pulling in the cable. May connect the wire rod 6 directly to the focusing portion 5.

The pulling guide member 3 formed on the flattened curved body may be made of any material as long as it is deformable and has a restoring property, but various plastic or rubber sponges are preferable. In addition, a material having air permeability is preferable, and further, the traction guide member 3
Is preferably covered with a net 31 formed like a net. The reason why the pulling guide member 3 is air-permeable and is preferably covered with a net 31 formed in a mesh shape is that the narrow space where the cable 8 below the pulling tool 1 is laid. The tractor 1 is subjected to the negative pressure Venturi effect, that is, the suction action toward the cable 8 side, by the air flow 9 ′ flowing therethrough. The air passing through the gap between the cable 8 and the cable 8 reduces the suction action on the cable 8 side due to the negative pressure Venturi effect, so that the suction of the pulling tool 1 on the cable 8 side can be prevented.

Further, it is preferable that the parachute-shaped pulling member 2 is biased rearward with respect to the pulling guide member 3, so that a wide space above the cable laying pipe 7 in the pipeline. When the traction tool 1 that moves by the wind pressure effect of the airflow 9 flowing through it passes through the narrow area due to the meandering of the cable 8, even if the preceding traction guide member 3 stagnates in the narrow area, it is formed in a parachute shape. Since the traction member 2 can maintain the wind pressure effect of the air flow 9, the traction guide member 3 is pushed backward.
When passing through the narrow area of the traction guide member 3, the traction guide member 3
Can help the movement of.

Further, the traction guide member 3 is arranged on the lower surface side of the traction member 2 and exerts its original function as the traction tool 1. Therefore, the traction guide member 3 is the lower surface side of the traction member 2. It is preferable that the traction guide member 3 is fixed to the traction member 2 by adhesion or sewing.
It does not have to be fixed. The reason is that the pulling tool 1 in which the wire 6 is connected to the focusing portion 5 of the pulling cord 4
If the pulling guide member 3 is arranged on the lower surface side of the pulling member 2 when the cable is inserted into the pipe line of the cable laying pipe 7, the wind pressure effect by suction or pressure feeding in the pipe line is formed in a parachute shape. Since the wind pressure effect of the traction member 2 is large, and the wind pressure effect of the traction guide member 3 formed on the slightly flat curved body is small, the traction member 2 is on the upper side and the traction guide member 3 is on the lower side by each wind pressure effect. This is because the pulling guide member 3 is naturally oriented toward the lower surface side of the pulling member 2 by being directed.

[0020]

As described above, according to the present invention, when the tow tool moves by receiving the airflow flowing in the wide space above in the conduit of the cable laying pipe, the tow tool has a parachute shape. The drawn traction member easily fits into the pipeline inner wall side of the wide area due to the wind pressure effect of the airflow flowing in the wide area, and because the closeness to the pipeline inner wall in the wide area is good, the traction force of the traction tool due to the wind pressure effect is increased. Can be increased.

At the same time, the traction guide member of the traction device is
The negative pressure Venturi effect due to the airflow flowing through the narrow space where the cable on the lower side of the tow tool is laid, that is, the suction action to the cable side is received, but the tow guide member is deformable and has a restoring property. Since it is formed into a flat curved surface body, it is difficult to adapt to the cable side of the wide area due to the wind pressure effect of the airflow flowing in the wide area, and the close contact with the cable in the wide area is slow, so It is possible to prevent the pulling device from being attracted to the cable side due to the negative pressure Venturi effect, and moreover, the pulling force of the pulling device due to the wind pressure effect can be increased by the amount that the pulling guide member is hardly affected by the negative pressure venturi effect. it can.

Therefore, it is possible to increase the traction force of the pulling tool for further inserting the wire for pulling the cable into the conduit of the cable laying pipe and to prevent the pulling tool from being attracted to the laying cable side. As a result, the wire rod can be quickly inserted into the conduit of the cable laying pipe.

[Brief description of drawings]

FIG. 1 is a partial vertical cross-sectional side view of a pipe running method in a cable laying pipe of the present invention.

FIG. 2 is a vertical cross-sectional rear view taken along the line AA in FIG.

FIG. 3 is an explanatory view showing a wire passage state of a conventional cable laying pipe in a pipe wire-laying method, in which (a) is a partial vertical side view thereof, and (b) is a vertical rear view thereof.

FIG. 4 is an explanatory view showing a state in which the conventional cable laying pipe cannot be passed by the in-pipe running method, in which (a) is a partially longitudinal side view thereof, and (b) is a longitudinal rear view thereof.

[Explanation of symbols]

1 Tow 2 Towing member 3 Traction guide member 31 net 4 tow string 5 Focusing section 6 wire rod 7 Cable laying pipe 8 cables

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takayoshi Shimura             3-23-14 Takanawa, Minato-ku, Tokyo Japan Com             In cis corporation (72) Inventor Daisuke Kataoka             3-23-14 Takanawa, Minato-ku, Tokyo Japan Com             In cis corporation (72) Inventor Nobukatsu Ike             Stock Exchange, 1-10-6 Takaban, Meguro-ku, Tokyo             Inside Hakko (72) Inventor Hiroaki Kaneko             3-18-3 Daikan, Daiwa City, Kanagawa Stock             Company Hakko Technology Development Center (72) Inventor Junta Sakurai             3-18-3 Daikan, Daiwa City, Kanagawa Stock             Company Hakko Technology Development Center F-term (reference) 5G369 AA19 BA04 DC03 EA01

Claims (3)

[Claims] 1. An in-pipe passage construction method for inserting a wire rod for further pulling a cable into a pipe line in which a cable is laid, wherein the pulling member is formed in a parachute shape, and is arranged on a lower surface side of the pulling member. The pulling tool is formed by a pulling guide member that is provided on the curved flat flat body that is deformable and has a restoring property, and a focusing portion that focuses the pulling string provided on the pulling member and the pulling guide member. The wire rod is inserted into the conduit of the cable laying pipe by inserting and drawing or sucking a towing tool in which the wire rod is connected to the focusing portion of the tow cord into the conduit of the cable laying pipe and sucking or pumping. In-pipe line construction method for cable laying pipe. 2. The conduit line in a cable laying pipe according to claim 1, wherein the pulling guide member formed on the flattened curved surface body is covered with a net formed in a mesh shape. Construction method. 3. The conduit running method for a cable laying pipe according to claim 1, wherein the parachute-shaped pulling member is biased rearward with respect to the pulling guide member.