JP2003070144A - Water proof treatment structure and method for insulated cable branch part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water proof treatment structure and a method for an insulated cable branch part capable of achieving a simplified work and a high water tightness by filling a foaming seal material having excellent properties over the entire region of a protective cover inside which accommodates the branch part so as to prevent the stress corrosion disconnection due to infiltration of rain water at a branch portion such as a high tension over-head power distribution cable and a high-tension lowering cable or the like. SOLUTION: A conductor connecting part which connects a main cable 10 to conductors 11, 13 of a branch cable 12 with a sleeve 14 is accommodated in a protective cover 20 and set. The protective cover 20 is a halved type formed of a left side cover 21 and a right side cover 22, and are joined together in a lock state after the conductor connecting part is accommodated. An RTV silicone foam as a sealing material 15 is injected from a sealing material filling port 24 and filled therein. The filling work can be done by a simple work, only filling the material by injection into every particular corner within the protective cover 20, so that the satisfactory water tightness can be achieved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof treatment structure and a waterproof treatment method for an insulated electric wire branch portion, which protects a branch portion of a portion where a high voltage down line and the like branch from a main line of an overhead high voltage distribution line or the like from rainwater.

[0002]

2. Description of the Related Art In the case of an overhead high-voltage distribution line, rainwater penetrates into its detention point or a branch point with another overhead high-voltage distribution line or a high-voltage down line to cause stress corrosion and prevent accidents such as disconnection. Is waterproofed. That is, at the branch point, the conductors exposed by peeling off the insulating coatings of both the main line and the branch line are bound together by a terminal fitting or the like. Each terminal metal fitting is covered from the outside with an insulating protective cover to protect the entire branch location. Since the protective cover is provided with electric wire outlets through which the main line and the branch line are drawn out at both ends of the cover, it is necessary to perform a waterproof treatment so that rainwater does not enter the inside of the cover through the electric wire outlets.

Conventionally, taping has been used as a conventional waterproof treatment means applied to such an electric wire outlet.
However, it is difficult to maintain the required water-tightness for a long period of time because taping reduces the adhesive strength due to deterioration of the tape over time. As an alternative technique to such taping processing, there is an electric wire branch connection portion disclosed in Japanese Patent Laid-Open No. 5-146045. This will be schematically described with reference to FIG.

A portion of the overhead insulated wire where the branch line 2 branches from the main line 1 is peeled off to expose the conductors 3 and 4, and the conductors 3 and 4 are bound together and compression-coupled with a branch sleeve 5. The conductor connecting portion 6 is formed. The front and rear branching point regions including the conductor connecting portion 6 are covered and protected by a half-divided insulating protective cover 7, and the waterproof compound 8 is provided on the half-divided surface of the protective cover 7 shown by the shaded portion in the figure. Is attached. Further, the electric wire outlets 7a, 7b, 7c, which are the entrances and exits of the main line 1 and the branch line 2 provided at both ends of the protective cover 7, are also filled with the waterproof compound 8 to prevent the intrusion of rainwater and ensure the watertightness. .

The conventional waterproof structure shown in FIG. 5 has the following problems. The protective cover 7 has a waterproof compound 8 on the half surface of the cover to ensure waterproofness.
Are uniformly and evenly filled and attached, but such attachment work requires skill and takes time. Further, it is also difficult to bind the conductor connecting portion 6 by using the branch sleeve 5. Furthermore, since the protective cover 7 has a unique shape, a conventional type cover cannot be used, and it is uneconomical to manufacture a specially designed cover.

In order to solve such a problem, the present applicant has previously proposed a technique of applying a fluid silicone rubber over the conductor connecting portion and its periphery, and has attempted to simplify waterproofing work and the like.

However, the application of the fluid silicone rubber has a surface which is difficult to apply due to dripping during application work.
There is room for improvement in terms of work efficiency due to the need for multiple coatings.

As described above, the common points of several examples of the prior art, such as the taping process, the waterproof compound adhesion process on the half-divided surface of the protective cover, and the silicone rubber application process on the conductor connecting portion, are common to only the required local sealing material. It is that it is given. If a simple work can be performed and satisfactory waterproofness is to be obtained, it is conceivable to fill the entire area of the inside of the protective cover with sealing material instead of local waterproofing as in the above few examples. One of the means is to fill the well-known urethane foam.

[0009]

However, while the foamed urethane foam can be easily filled inside the protective cover, at the time of foaming, there are many "open cells" in which adjacent ones of the cells are connected in a chain. To generate. Therefore, once water such as rainwater partially penetrates, there is a disadvantage that the infiltrated water reaches the conductor connecting portion through the chained bubbles. In addition, the urethane foam has a brittle material after curing, and if the wire shakes due to wind force, etc., the biteness and adhesion with the conductor connection part will be impaired, and gaps and cracks will occur, making it impossible to secure the required waterproofness. There are many defects.

Therefore, an object of the present invention is to provide a characteristic over the entire inside of the protective cover for accommodating the branch point in order to prevent the stress corrosion disconnection due to the intrusion of rainwater etc. at the branch point such as the overhead high voltage distribution line and the high voltage down line. It is an object of the present invention to provide a waterproof treatment structure and a waterproof treatment method for an insulated wire branching portion that can realize a simple work and a high degree of waterproofness by being filled with an excellent foaming sealing material.

[0011]

In order to achieve the above object, a waterproof treatment structure for an insulated wire branch portion according to a first aspect of the present invention is shown in FIGS. 1 and 2 (a), (b). As shown, each of the insulated wires is a main wire 10 to a branch wire 1
The connecting member 14 connects the conductors 11 and 13 in the part where 2 branches.
The conductor connecting portion and the peripheral area including the conductor connecting portion are bundled and connected with each other to cover and protect them, and the main wire 10 and the branch wire 12 are drawn out from the electric wire outlet on one end side, and the electric wire on the other end side. A protective cover 20 that allows only the main line 10 to be pulled out from the outlet, and a foaming foam that is foamed in the form of closed cells to fill every corner of the inside of the protective cover 20 and becomes a sponge after curing. Seal material 15
And seal tapes 30 and 31 for securing water tightness by winding the electric wire outlets at both ends of the protective cover 20 together with the main wire 10 and the branch wire 12.

From the above, the structure according to claim 1 operates as follows. Both conductors 11 of the main line 10 and the branch line 12,
The protective connector 20 in the set state is accommodated in the conductor connecting portion to which the 13 is connected, and the foaming sealing material 15 is filled therein.
For example, RTV silicone foam is suitable for the sealing material 15, and most of it is foamed as closed cells at the time of foaming. Therefore, even if rainwater or the like penetrates through the main line 10 or the branch line 12 from the outside, it is partially foamed. It stops only when the rainwater enters and does not reach the conductor connection part. In addition, the sealing material 15 extends to every corner of the inside of the protective cover 20 and follows the inner shape of the cover, and hardens into a sponge shape. Therefore, all the voids such as the gap with the conductor connecting portion in the protective cover are completely filled with the sealing material 15.
In addition, by winding the seal tapes 30 and 31 around the electric wire outlets at both ends of the protective cover 20, rainwater and the like are prevented from entering the cover from the outside through the main line 10 and the branch line 12. As a result, satisfactory water tightness at the conductor connecting portion can be secured by a simple operation of filling the sealing material 15.

Further, in the waterproof structure of the insulated wire branch portion according to the second aspect, as shown in FIGS. 1 and 2A and 2B, the sealing material filling hole 2 is provided at an appropriate position of the protective cover 20.
4 is provided so as to penetrate therethrough.

From the above, the structure according to claim 2 operates as follows. If the sealing material filling hole 24 is provided at a convenient place of the protective cover 20, the foaming sealing material 15 is inserted into the sealing material filling hole from the state where the conductor connecting portion is accommodated and set inside the cover. Since it is only injected from 24, it can be greatly simplified without requiring special skill in the processing work.

Further, in the waterproof treatment structure of the insulated wire branch portion according to the third aspect of the invention, as shown in FIGS. 3A, 3B and 4, the protective cover 20 is substantially symmetrical from the central axis to the left and right. The halves 21 and 22 are separable in shape, and are characterized in that cover locking means (21d, 22d) are provided on both sides of one side and the other side of the halved surfaces, respectively.

From the above, the structure according to claim 3 operates as follows. Since the protective cover 20 is a half-split type and is made up of two pieces, it is convenient and convenient to accommodate and set the conductor connecting portion without any labor. After accommodating the conductor connecting portion, the work of locking the two half-divided covers 21 and 22 with the lock pin 21d and the lock hole 22d of the cover locking means provided on both half-divided surfaces to integrate them. It can be done quickly and easily.

On the other hand, according to a fourth aspect of the present invention, there is provided a waterproof treatment method for a branched portion of an insulated wire, wherein conductors 11 and 13 at a portion where a main wire 10 which is an insulated wire branches or a branch wire 12 branches or gathers. The process of bundling with the member 14 and accommodating and setting the conductor connection portion inside the protective cover 20, the main wire 1 from the electric wire outlets at both ends of the protective cover 20.
After pulling out the 0 and the branch line 12, the foaming sealing material 15 is uniformly foamed and filled in all the inner corners of the protective cover 20, and is cured into a sponge shape following the inner shape of the cover. Step of making, main line 10 and branch line 12
The step of wrapping the seal tapes 30 and 31 around the electric wire outlets at both ends of the protective cover 20 from which the water is drawn out to ensure waterproofness.

From the above, in the method according to the fourth aspect, with respect to the protective cover 20 after accommodating the conductor connecting portion,
It is a great advantage that the sealing material 15 made of RTV silicone foam can be simply injected and filled. In other words, in the past, with the protective cover in a half-split state, with the half-split surface open, a waterproof compound was applied to the half-split surface, and fluid silicone rubber was applied to the conductor connection part, etc. It is not efficient because it takes time and requires careful attention. According to this method, a simple operation of injecting and filling the foaming sealing material 15 having excellent characteristics of RTV silicone foam is all that is required, and moreover, every detail in the protective cover 20 can be filled and spread. Satisfactory waterproofness can be secured.

According to a fifth aspect of the present invention, there is provided a waterproof treatment method for a branched portion of an insulated wire, wherein the protective cover 20 is inclined at one end side in the longitudinal direction and is inclined at the other end side, and the other end of the higher position is inclined. It is characterized in that the sealing material 15 is injected and filled from a sealing material filling hole 24 provided on the side.

From the above, according to the method of claim 5, the sealing material 15 is inserted from the sealing material filling hole 24 into the protective cover 20.
Since it is a method of injecting and filling, the protection cover 20 can be tilted obliquely to improve the efficiency of the circumference and flow condition of the sealing material 15 being filled. The idea that the protective cover 20 is inclined so as to improve the flow condition is an advantage that cannot be found in the related art.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of a waterproof treatment structure and a waterproof treatment method for an insulated wire branch portion according to the present invention will be described in detail with reference to the drawings. Figure 1
It is a side view by the partial cross section which shows the structure of 1st Embodiment. In this case, both are insulated wires. In this case, a branch line 12 such as a high voltage down line branches from the main line 10 of the overhead high voltage distribution line,
The area of the branch point is housed in the insulating protective cover 20 to cover and protect it, so that it is waterproof against rainwater and the like.

At the branch point, the middle of the main line 10 and the branch line 1
The insulation coating on the tip of the wire 2 is peeled off to expose the conductors 11 and 13 and bind them together, and the terminals 11 or the sleeve 14 shown in the drawing is caulked or compression-tightened. In this way, both conductors 11 and 13 are compressed and tightened, and the main line 10 and the branch line 1
2 is connected. A protective cover 20 is placed over the conductor connection including the sleeve 14 and the surrounding from the outside.

As shown in FIGS. 2 (a) and 2 (b), the protective cover 20 is made of plastic in which the cover body A is molded in a bag shape in this case. Has an opening edge 23 that can be opened and closed, and both ends in the longitudinal direction are electric wire outlets 25 and 26. The main line 10 and the branch line 12 are drawn out from the electric wire outlet 25 at one end, and only the main wire 10 is drawn out from the electric wire outlet 26 at the other end. In addition, the opening edge 23
Coupling flanges 21c and 22c are provided long along both sides of the. The coupling flange 21c on one side has, for example, three lock pins 21d, which are cover locking means according to the present invention, which are juxtaposed along the inner surface, and the coupling flange 22c on the other side has the three lock pins on one side. 21d
The three lock holes 22d into which are inserted are provided so as to penetrate therethrough. By fitting both lock pins 21d and lock holes 22d with one touch, the opening edge 23 is closed in a locked state.

Further, a sealing material filling hole 24 is provided penetrating at a suitable position on one side of the protective cover 20 in the longitudinal direction, and the sealing material 15 is injected from the sealing material filling hole 24 to minute corners inside the cover. Are filled to the full state.

As the material of the sealing material 15, in this example, RTV (room temperature curing type) silicone foam is used. That is, the sealing material 15 has a closed-cell shape when foamed, and even after curing, even the minute corners inside the protective cover 20 follow the shape even if the inside of the cover has a complicated shape. It is preferable that the resin penetrates into every corner and hardens to form a sponge, and in that sense, foamed RTV silicone foam is used. In the case of this foamed RTV silicone foam, the silicone itself has water repellency and not only repels water, but even if there is partial infiltration of rainwater etc. due to the closed cells, it can infiltrate into other parts. It has the property of stopping propagation. Therefore, by covering the exposed conductors 11 and 13 from the outside with the sealing material 15 made of RTV silicon foam in a close contact state, it is effective to secure the watertightness.

As the foamed RTV silicone foam as the sealing material 15, for example, Toray Dow Corning Silicone SE1900 RTV foam can be used. In that case, by mixing and stirring the two liquids at a ratio of 1: 1 at room temperature, it is possible to foam 3 to 4 times the closed cell ratio of 50% or more in 2 to 3 minutes.

Next, the waterproof treatment method of the present invention applied to the insulated electric wire branch portion composed of the above-mentioned members will be described with reference to FIG.

At the branch point where the main line 10 of the overhead high-voltage distribution line is branched from the main line 10 such as a high-voltage down line, the stripped main line 10 and the conductors 11 and 13 of the branch line 12 are bound together, and the sleeve 14 is placed on the bundle. Cover and connect by tightening compression.

Subsequently, the entire peripheral region including the conductor connecting portion including the sleeve 14 is covered and covered with a protective cover 20 from the outside. At this time, the lock pin 21d and the lock hole 22d in the coupling flanges 21c and 22c are fitted and locked with one-touch with a click feeling (moderation). When the protective cover 20 is attached in this way, the main wire 10 is pulled out from the electric wire outlet 25 on one end side.
And the branch line 12 are pulled out, and the wire outlet 2 on the other end side
Only the main line 10 is pulled out from 6.

Next, R is injected from the sealing material filling hole 24.
The sealing material 15 of TV silicone foam is filled inside the cover. The sealing material 15 is foamed as closed cells by taking advantage of the characteristics of the RTV silicone foam, and while being cured, is filled evenly in every corner inside the protective cover 20. After filling,
It is desirable to put a filling in the sealing material filling hole 24 for sealing.

At the time of filling, the left side of the protective cover 20 in the figure is lowered and the right side thereof is raised, that is, the sealing material filling hole 24.
By injecting the sealing material 15 with the
The flow and rotation of the sealing material 15 to the left end side, which is the lower position inside the cover, is improved, and it is possible to effectively fill every corner.

It should be noted here that the sealing material 15 can be injected and filled into the inside of the protective cover 20 through the sealing material filling hole 24. In the conventional example of FIG. 5, the insulating cover 7
The structure in which the waterproof compound 8 was attached only to the half-divided surface of the cover was adopted. Further, in the previous proposal by the applicant, a structure in which the fluid silicone rubber is applied to the conductor connecting portion has been adopted. In any of the waterproof treatment structures, the sealing material is filled with the protective cover in a half-opened state, so that the problems and inconveniences caused by the filling are as described above. In the case of this example, by filling with the protective cover 20 in the closed state, the sealing material 15 spreads to every corner inside the cover, and a high degree of watertightness can be secured. It is common sense that if the protective cover 20 is obliquely filled, the flow and the circumference of the sealing material 15 will be improved.
This is possible because the protective cover 20 can be filled in the closed state, which cannot be found in the above-mentioned prior arts.

After the sealing material 15 is filled in this way, the electric wire outlets 25 and 26 at both ends of the protective cover 20 from which the main line 10 and the branch line 12 are drawn out are put together with the seal tape 3.
By winding 0 and 31 and binding them tightly, the waterproofness is ensured so that rainwater or the like does not pass through the main line 10 or the branch line 12 from the outside to enter the inside of the cover, and the rainwater or the like permeates the conductors 11 and 13. To prevent.

In the above description, the form in which the seal material filling hole 24 is provided and the seal material 15 is injected from the hole has been described.
When such a sealing material filling hole 24 is not provided, the following procedure is also possible. In that case, the cover main body A is set in a state where the opening edge 23 is opened in the upper direction in the vertical direction, and the main body 10 and the branch line 1 are set from the electric wire outlets 25 and 26 at both ends.
2 is pulled out and tightly bound with the sealing tapes 30 and 31. After that, the sealing material 15 is passed through the gap of the opening edge 23 in the opened state.
Alternatively, the cover body A may be locked by fitting the lock pin 21d and the lock hole 22d of the coupling flanges 21c and 22c with each other.

However, rather than the method of filling the sealing material 15 with the opening edge 23 in the upward half-opened state, the idea of "spreading the foamed sealing material to every detail inside the protective cover" is the gist of the present invention. Then, it can be said that the method of providing the sealing material filling hole 24 and injecting the sealing material from the filling hole is highly efficient and is preferable in that a high degree of watertightness can be secured.

On the other hand, FIGS. 3A, 3B and 4 show
The 2nd Embodiment concerning this invention is shown. First above
In the embodiment, the protective cover 20 is formed in a bag shape, but in the second embodiment, the left cover 21 and the right cover, which are two semi-cylindrical bodies that can separate the cover body left and right from the vertical axis. The cover 22 is a half type.

The left side cover 21 has electric wire outlets 21a and 21b having semicircular openings at both ends of the cover.
A long joint flange 21c is provided along an opening edge 23 which is a joint surface with the right cover 22.
1c has three lock pins 21d protruding side by side on the inner surface. Similarly, the right side cover 22 also has electric wire outlets 22a and 22b, both ends of which are opened in a semicircular shape.
The main line 10 and the branch line 12, and only the main line 10 goes in and out of the circular shape by being combined with 1b. Further, the right side cover 22 is also provided with a long coupling flange 22c along the opening edge 23, and three lock holes, which are cover lock means of the other side, into which the three lock pins 21d are fitted are arranged side by side on the inner surface of the coupling flange 22c. 22d is provided so as to penetrate therethrough. The lock pin 21d and the lock hole 22d are fitted with each other by one-touch, so that the left cover 21 and the right cover 22 are coupled in a locked state to form one protective cover 20.

Further, in this case, for example, the sealing material filling hole 24 is provided penetrating one side of the right side cover 22, and the sealing material 15 is injected from the sealing material filling hole 24 to the minute corners inside the cover. Are filled to the full state.

Next, the waterproof processing method in the second embodiment will be described. As described in the first embodiment,
A sleeve 14 is placed over the conductors 11 and 13 of the main line 10 and the branch line 12 which are bound together, and the sleeve 14 is compressed and connected for connection.

Next, the protective cover 20 is covered with the conductor connecting portion including the sleeve 14 so as to cover the entire peripheral region from the outside, and the lock cover 21d is provided on each of the left side cover 21 and the right side cover 22. And the lock hole 22d are fitted to each other and locked. When the protective cover 20 is attached in this way, the electric wire outlet 21a on one end side,
The main line 10 and the branch line 12 are drawn out from 22a, and only the main line 10 is drawn out from the electric wire outlets 21b and 22b on the other end side.

Then, in the same manner as in the above-described first embodiment, the sealing material 15 is injected from the sealing material filling hole 24 to fill the inside of the cover with the sealing material 15 of RTV silicone foam. After filling the sealing material 15, the seal tapes 30 and 31 are wrapped around and tightly bound together with the electric wire outlets at both ends of the protective cover 20 from which the main line 10 and the branch line 12 are drawn out. Make sure that the conductors 11 and 13 are waterproof so that rainwater, etc. does not penetrate inside the cover.
Prevent rainwater and the like from penetrating into.

Waterproofing test: An example in which the sealing material 15 of this example was filled with RTV silicone foam as described above, a conventional example 1 in which fluid silicone rubber was applied, and a conventional example in which foamed urethane foam was filled. The "simple waterproofing test" and the "rainwater intrusion prevention test" were carried out on the waterproofing structure of each insulated wire branching part of No. 2 as follows.

1. As a sample of each of the insulated wire branch portions according to the simple waterproof test example, the conventional example 1 and the conventional example 2, a main line and a branch line drawn together from one side around the conductor connection part, and a main line drawn from the other side. Was produced with a total length of about 1000 mm. Each of these samples was immersed in an ultraviolet fluorescent solution having a depth of about 150 mm, which was placed in a water tank, and after 3 hours or more, it was observed how the ultraviolet fluorescent solution as a test solution leaked from the end of the sample. If the UV fluorescent liquid leaks out from the end of the sample, it means that if the UV fluorescent liquid enters the branch part centered on the conductor connection part, it will penetrate through the conductor and penetrate the end of the main line or branch line of the sample. It's leaking from the department, so I'm talking about the meaning of observing it. The results are shown in Table 1.

2. As a sample of the insulated wire branching part according to the rainwater intrusion prevention test example, the conventional example 1 and the conventional example 2, the length on the side where the main line and the branch line are pulled out together around the conductor connection part is about 2200 m.
m, the length on the side where only the main line is drawn out was about 2200 mm, and a total length of about 4400 mm was produced. Each of these samples is housed and set in a test tube made of stainless steel having a length of 2000 mm such that the conductor connection portion is at the center. Both ends of the stainless steel test tube are closed with a flange to ensure gas-liquid tightness. The main line and the branch line are watertightly and airtightly inserted and pulled out from the flange on one end side. Only the main line of the flange on the other end side is inserted and pulled out with watertightness and airtightness.

In this way, each sample was housed and set, and the test liquid containing the ultraviolet fluorescent liquid was filled in the cylinder of the stainless steel test cylinder which secured the gas-liquid tightness, and the pressure of the test liquid was adjusted to 0.
The pressure was maintained at 5 atm for 24 hours, and the state of leakage of the ultraviolet fluorescent liquid was observed from the end of each sample in that state. The results are shown in Table 1.

Table 1 shows the above two test results,
In addition to this, the work difficulty in manufacturing the branch portion of the total of three samples of Examples and Conventional Examples 1 and 2 was also evaluated, and the comprehensive results are shown. In Table 1, workability was evaluated by the symbols “◯: good”, “Δ: normal”, and “x: bad”. In addition, in the simple waterproof test, leakage of the test liquid was evaluated by the symbols “◯: no” and “x: present”. In addition, in the rainwater intrusion prevention test, leakage of the test solution was evaluated by the symbols "○: No" and "X: Yes".

[0047]

[Table 1]

Discussion: As is apparent from Table 1, the workability of the sample of Conventional Example 1 coated with the fluid silicone rubber was “Δ”, which was normal. No leakage was found in the simple waterproof test, and a rating of "○" was obtained. Leakage was recognized in the rainwater intrusion prevention test, and the evaluation was “x”. Therefore, the overall results from these were marked as “x”, and the evaluation was unavoidable. In the case of the sample of Conventional Example 2 filled with urethane foam, the workability is “◯”, which is good. Leakage was recognized in the simple waterproof test and evaluated as "x". Leakage was also observed in the rainwater intrusion prevention test, and the evaluation was “x”. Therefore, the comprehensive evaluation is also unsuitable as "x". In the case of the sample of the example of the RTV silicone foam filling construction, the workability was “◯”, which was good. In addition, no leakage was found in the simple waterproof test, and a rating of "○" was obtained. Also in the rainwater intrusion prevention test, no leakage was observed, and a rating of "○" was obtained. Therefore, in the case of the example according to the present invention, a very satisfactory overall evaluation “◯” was obtained.

[0049]

As described above, in the waterproof treatment structure for an insulated wire according to claim 1 of the present invention, the inside of the protective cover for accommodating the conductor connecting portion connecting both conductors of the main line and the branch line is filled. For example, RTV silicone foam is suitable as the foamable sealing material, and most of them are foamed as closed cells at the time of foaming. Therefore, even if rainwater or the like enters from the outside through the main line or the branch line, It stops only by partial infiltration of rainwater and does not reach the conductor connection. In addition, since the sealing material spreads to every detail inside the protective cover and follows the inner shape of the cover and hardens into a sponge shape, all voids such as gaps with the conductor connection part in the protective cover are formed. Filled up with sealing material.
In addition, by winding a sealing tape around the electric wire outlets at both ends of the protective cover, rainwater and the like are prevented from entering the inside of the cover from the outside through the main line and the branch line. As a result, it is possible to secure a satisfactory water tightness in the conductor connecting portion by a simple operation of filling the sealing material.

Further, in the waterproof structure of the insulated wire branch portion according to the second aspect of the present invention, if the sealing material filling hole is provided at a convenient portion of the protective cover, the conductor connecting portion is housed inside the cover. Since the foamable sealing material is simply injected from the sealing material filling hole in the state of being set, the processing work can be greatly simplified without requiring special skill.

Further, in the waterproof treatment structure of the insulated wire branch portion according to the third aspect of the invention, since the protective cover is a half-split type, it takes a lot of work to house and set the conductor connecting portion. It is convenient for me. After accommodating the conductor connection portion, the work until the two half-split covers are locked and integrated by the cover locking means provided on both half split surfaces can be performed quickly and easily.

According to the fourth aspect of the present invention, in the waterproof treatment method for the insulated wire branch portion, the sealing material made of RTV silicone foam can be simply injected and filled into the protective cover after accommodating the conductor connection portion. That is a great advantage. In other words, in the past, with the protective cover in a half-split state, with the half-split surface open, a waterproof compound was applied to the half-split surface, and fluid silicone rubber was applied to the conductor connection part, etc. It is not efficient because it takes time and requires careful attention. In this method, RT
V Silicone foam, which is a foaming sealing material with excellent characteristics, can be simply injected and filled, and it is possible to fill and spread all the details in the protective cover, so that satisfactory watertightness can be achieved. Can be secured.

Since the method for waterproofing the insulated wire branching portion according to claim 5 is a method of injecting and filling the sealing material into the protective cover through the sealing material filling hole, the protective cover is inclined and filled. It is possible to improve the efficiency of the circumference and flow of the seal material inside. The idea of tilting the protective cover to improve the flow condition is an advantage that cannot be found in the prior art.

[Brief description of drawings]

FIG. 1 is a first structure for waterproofing an insulated wire according to the present invention.
It is a side view by the partial cross section which shows embodiment.

FIG. 2A and FIG. 2B are an assembly plan view and an assembly side view showing the bag-like protective cover according to the first embodiment.

3 (a) and 3 (b) are an assembly plan view and an assembly side view showing a half-divided protective cover according to a second embodiment.

FIG. 4 is an exploded perspective view showing a protective cover of the second embodiment.

FIG. 5 is a side view showing the inside of a conventional waterproof structure.

[Explanation of symbols]

10 Main line 11 of aerial high voltage distribution line 11, 13 Conductor 12 Branch line 14 Sleeve 15 Seal material 20 made of RTV silicone foam Insulating protective cover 21, 22 Left side cover and right side cover 21a, 22a Electric wire outlet 21b, 22b Electric wire outlet 21d Lock pin (cover locking means) 22d Lock hole (cover locking means) 23 Opening edge 24 Seal material filling hole 25, 26 Electric wire outlet 30, 31 Seal tape

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ identification code FI theme code (reference) H01R 4/70 H02G 1/02 305E H02G 1/02 305 1/14 A 1/14 7/00 Y 7 / 00 H01B 7/28 EF term (reference) 5G309 EA03 5G313 FA01 FC01 FC08 FD06 5G355 AA03 BA02 BA11 CA19 CA26 5G367 BA02 BB04 5G375 AA02 BA26 BB44 BB48 CA02 CA14 CB04 CB10 DB23 DB44 DB45 EA17

Claims (5)

[Claims] 1. An electric wire outlet on one end side for accommodating and protecting a conductor connecting portion connecting conductors in a portion where a branch line branches from a main wire which is an insulated electric wire and a peripheral region including the conductor connecting portion. The main line and the branch line are drawn out from the main line and the main line is drawn out from the electric wire outlet on the other end side. It is composed of a foaming sealing material that turns into a sponge after curing, and sealing tape that secures water tightness by winding the wire outlets at both ends of the protective cover together with the main line and branch lines. Waterproof structure of the insulated wire branch part. 2. The waterproof treatment structure for an insulated wire branching portion according to claim 1, wherein a sealant filling hole is provided at an appropriate position of the protective cover. 3. The protective cover is of a half-divided type that can be separated from the central axis line to the left and right in a substantially symmetrical manner, and cover locking means is provided on both one side and the other side of the half-divided surface. The waterproof treatment structure for an insulated wire branch portion according to claim 1 or 2, characterized in that. 4. A step of accommodating and setting a conductor connecting portion, in which conductors of a branch line are branched from a main wire which is an insulated electric wire, are housed inside a protective cover, and the main wire is drawn from an electric wire outlet at both ends of the protective cover. After pulling out the branch line and the branch line, a step of uniformly filling the inside of the protective cover with a foaming sealing material while foaming it in the form of closed cells and curing it into a sponge shape following the internal shape of the cover, protection A method for waterproofing a branched portion of an insulated electric wire, which comprises a step of winding the electric wire outlets at both ends of the cover together with a main line and a branch line with a sealing tape to ensure waterproofness. 5. The protective cover is inclined with one end side in the longitudinal direction being low and the other end side being highly inclined, and the seal material is injected through a seal material filling hole provided on the other end side of the higher position to fill the protective cover. The method for waterproofing a branched portion of an insulated wire according to claim 4, wherein: