JP2001229995A - Molding structure and molding method of cable branch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a molding structure of a cable branch which has superior waterproofing performance. SOLUTION: The molding structure is a double-molding structure, comprised of: an inner molding part 11, in which a molding part 10, that insulates and protects the portion where a conductor 2a of a branch cable 2 has been connected to a conductor 1a of a trunk line 1 is molded by resin, to cover the connection of the conductors 1a, 2a, and an outer molding part 12, which is molded by resin to cover the inner molding part 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding structure and a molding method for a cable branch portion such as a CV cable (crosslinked polyethylene insulated vinyl sheath cable).

[0002]

2. Description of the Related Art In recent years, various types of solar systems for ordinary houses or for business use have been developed. The solar system is constructed by, for example, arranging a plurality of solar battery modules each including a plurality of solar battery cells on a roof or a roof of a building, and connecting them with a cable.

A power cable such as a CV cable is used to connect such a solar cell module or to connect electrical equipment such as a snow melting roof tile module or a tape heater module. In a CV cable, an insulator covering a conductor (strand) is made of PE (polyethylene), and a sheath material is made of PVC.

In laying a CV cable, when a branch line is branched from a main line, generally, as shown in FIG. To ensure the insulation of the branch section), the cable branch section is made of PVC (polyvinyl chloride).
At 201, it is molded.

[0005]

According to the structure in which the branch portion of the CV cable is molded with PVC (FIG. 11), high waterproof performance cannot be obtained because the adhesion between the PVC and the cable conductor is not good. There is a problem.

The present invention has been made in view of such circumstances, and provides a molding structure of a cable branch portion having excellent waterproof performance and a molding method suitable for molding such a molding structure. Aim.

[0007]

SUMMARY OF THE INVENTION According to the present invention, there is provided an inner mold portion formed by resin molding so as to insulate and protect a portion where a conductor of a branch cable is connected to a conductor of a trunk cable and to cover a connection portion of the conductor. And a double-molded structure including an outer mold portion formed by resin molding so as to cover the inner mold portion.

More specifically, a mold portion for insulating and protecting a branch portion of a CV cable in which an insulator is made of PE and a sheath material is made of PVC has a double structure consisting of an inner mold portion and an outer mold portion. The inner mold portion is formed of PE, and the outer mold portion is formed of PVC.

According to the mold structure of the present invention, since the mold portion for insulating and protecting the cable branch portion has a double molding structure, the resin of the inner mold portion is made of PE having good adhesion to the cable conductor. And the waterproof performance can be improved.

Here, when the mold portion has a double-molded structure, it is necessary to perform the molding of the inner mold portion and the molding of the outer mold portion twice, and when molding the outer mold portion, A displacement may occur between the inner mold part and the outer mold part. When such a displacement occurs, a thin portion is formed in the outer mold portion, and a desired waterproof performance cannot be obtained.

The molding method of the present invention has been made to solve such a problem. In the molding method, a positioning hole is formed at the time of molding an inner mold portion covering a connection portion of a cable conductor, and then a positioning pin is provided. Using the molding die, insert the positioning pin into the positioning hole of the inner mold part, position the molding die accurately with respect to the inner mold part, and inject resin into the molding die in this state. And characterized by molding an outer mold portion that covers the inner mold portion.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

First, as shown in FIG. 5, in the branch of the CV cable, the sheath material (PVC) 1c and the insulator (PE) 1b of the trunk cable 1 are peeled to expose the conductor 1a.
Next, a sheath material (PVC) 2c at the end of the branch cable 2
Then, the conductor (2a) is exposed by peeling off the insulator (PE) 2b, and the conductor 2a is connected to the conductor 1a of the trunk cable 1. In the example shown in FIG. 5, a part of the sheath members 1c and 2c of the trunk cable 1 and the branch cable 2 is peeled off at the branch portion to expose a part of the insulators 1b and 2b.

The present embodiment is a molding structure of the branch portion of the CV cable described above, and as shown in FIGS.
An inner mold portion 11 is resin-molded so as to cover a connection portion between the trunk cable 1 and the conductors 1a, 2a of the branch cable 2. Further, the outer mold portion 12 is resin-molded so as to cover the inner mold portion 11, and the entire mold portion 10 has a double-molded structure.

The resin of the inner mold portion 11 is made of PE. The inner molded portion 11 includes conductors 1a and 2a of the trunk cable 1 and the branch cable 2 and insulators 1b and 2b of each cable (including a part of the sheath members 1c and 2c).
In close contact with each outer peripheral surface.

The resin of the outer mold portion 12 is made of PVC. The outer mold portion 11 is in close contact with the outer peripheral surfaces of the sheath members 1 c and 2 c of the trunk cable 1 and the branch cable 2.

As described above, in the present embodiment, as the resin of the inner mold portion 11, the insulators 1b, 2
Since the same resin (PE) as b is used, the adhesion between the inner mold portion 11 and the insulators 1b and 2b is increased. Furthermore, since the same resin (PVC) as the sheath material 1c, 2c of the CV cable is used as the resin of the outer mold portion 12, the adhesion between the outer mold portion 12 and each of the sheath materials 1c, 2c also increases. Therefore, high waterproof performance due to the double waterproof effect can be obtained.

Next, a method of forming the mold structure shown in FIGS. 1 to 4 will be described with reference to FIGS.

First, the conductor 1a of the trunk cable 1 and the conductor 2a of the branch cable 2 are connected in the manner shown in FIG.

As shown in FIGS. 6A and 6B, the connecting portions of the conductors 1a and 2a are arranged in a cavity 101b of a molding die 101, and a molten resin (PE) is injected into the cavity 101b. Then, the inner mold portion 11 is formed (FIGS. 7A and 7B).

The molding die 101 of the inner mold portion 11 is provided with projections 101a... 101a at four positions of the upper and lower dies, respectively.
8a are formed in the positioning holes 11a,.
(A) and (B)).

After the molding of the inner mold portion 11 is completed, as shown in FIGS. 9A and 9B, the positioning pins 102a... 102a are placed in a positional relationship corresponding to the positioning holes 11a. The provided molding dies 102 are inserted into the corresponding positioning holes 11a with the respective positioning pins 102a, and the molding dies 102 are accurately positioned with respect to the inner mold portion 11.

In this state, after the molten resin (PVC) is injected into the cavity 102b of the molding die 102 to form the outer mold portion 12, the molding die 102 is opened. Thereby, it is possible to obtain the mold portion 10 having the structure shown in FIGS. 1 to 4, that is, the double molding structure including the inner mold portion 11 and the outer mold portion 12.

In the above embodiment, the inner mold portion 11 is made of PE and the outer mold portion 12 is made of PVC to form a double molded structure. However, the combination of the two types of resin is optional. It may be appropriately selected according to conditions such as the type of cable to be molded.

The present invention is applicable not only to the molding of the branch portion of the CV cable used for connection of the solar cell module, but also to the molding of the branch portion of various cables used for connection of electric equipment such as a snow melting tile module or a tape heater module. Applicable.

[0026]

As described above, according to the present invention,
Since the molding structure of the cable branch portion is a double molding structure composed of an inner molding portion and an outer molding portion, the resin of the inner molding portion can be made of PE having good adhesion to the cable conductor, and excellent. Waterproof performance can be ensured.

According to the molding method of the present invention, the molding die of the outer mold portion can be accurately positioned with respect to the inner mold portion in molding the above-mentioned double molding structure. The thickness does not become thin locally. As a result, stable waterproof performance can always be obtained.

[Brief description of the drawings]

FIG. 1 is a horizontal sectional view showing a structure of an embodiment of the present invention.

FIG. 2 is a plan view of the embodiment of FIG.

FIG. 3 is a sectional view taken along line XX of FIG. 2;

FIG. 4 is a sectional view taken along line YY of FIG. 3;

FIG. 5 is a diagram schematically illustrating an example of a branch portion of a CV cable.

FIG. 6 is an explanatory diagram of a molding method of the embodiment shown in FIGS.

FIG. 7 is an explanatory view of a molding method.

FIG. 8 is an explanatory view of a molding method.

FIG. 9 is an explanatory view of a molding method.

FIG. 10 is an explanatory diagram of a molding method.

FIG. 11 is a view schematically showing a conventional example of a mold structure of a cable branch portion.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main cable (CV cable) 1a Conductor 1b Insulator 1c Sheath material 2 Branch cable (CV cable) 2a Conductor 2b Insulator 2c Sheath material 10 Mold part 11 Inner mold part 11a Positioning hole 12 Outer mold part 101 Mold ( 101a Protrusion 102 Molding die (for molding outer mold part) 102a Positioning pin

Claims (3)

[Claims] 1. A molded part for insulating and protecting a portion where a conductor of a branch cable is connected to a conductor of a trunk cable, an inner molded portion which is resin-molded so as to cover a connected portion of the conductor, and covers the inner molded portion. Characterized in that the cable branch portion has a double-molded structure including the resin-molded outer mold portion. 2. A mold structure for insulating and protecting a branch portion of a CV cable in which an insulator is made of PE and a sheath material is made of PVC has a double structure including an inner mold portion and an outer mold portion. The molding structure of a cable branch part according to claim 1, wherein the inner molding part is molded by PE and the outer molding part is molded by PVC. 3. A method of molding a portion of a trunk cable in which a conductor of a branch cable is connected to a conductor of the main cable, wherein an inner mold portion is formed so as to cover the connection portion of the conductor, and the inner mold portion is positioned at the time of the molding. Forming holes, then using a molding die provided with positioning pins,
Insert the positioning pin into the positioning hole of the inner mold part to position the molding die with respect to the inner mold part,
In this state, a resin is injected into a molding die to form an outer mold portion covering the inner mold portion.