JPH05182705A - Protecting structure of wire connection - Google Patents

Abstract

PURPOSE:To realize the protecting structure of a wire connection which is superior in its waterproofing property, working efficiency and the stability of connection, concerning the protecting structure of the wire connection. CONSTITUTION:A contracting tube 11 is laid along the outside of a wire connection for protecting the wire connection and wires 12, 12' are inserted as they are in their fixed state into the contracting tube 11 before the contracting tube 11 shrinks. The wire connection is also equipped with a wire fixing tool 10 for holding the contracting tube 11 after this tube 11 shrinks. The wire fixing member 10 is formed in a cylindrical or prismatic shape as it can be inserted in the contracting tube 11, and one or two or more than two piercing holes 14, the number of which corresponds to the number of the connected wires, are formed longitudinally in the wire fixing member 10, or one or two or more than two wire fixing grooves whose number corresponds to the number of the connected wires are formed on the surface of the wire fixing member 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protective structure for an electric wire connecting portion using a shrinkable tube and an electric wire fixture.

[0002]

2. Description of the Related Art Conventionally, a shrink tube has been widely used for connection of power cables and terminal treatment.
(Reference: Japanese Patent Application No. 58-15355, USP351)
5798) A cable connection processing method using this shrinkable tube will be described with reference to FIG. This uses the electric wire holder 1 as shown in FIG. This electric wire holder carries a contraction tube 5 in an elastically expanded state by one end of a cylindrical electric wire fixture 2 and a cylindrical plastic core 4 having a spiral cut 3. Next, as shown in FIG. 2B, after inserting the electric wire 6 into the electric wire holder 1, the end portion 4a of the plastic core 4 is pulled in the direction of the arrow A and unwound along the notch 3, As shown in FIG. 3C, the shrink tube 5 shrinks to tightly tighten the electric wire 6.

This method has the advantage that simple and quick processing is possible when there is only one electric wire, but since the shrinkable tube 5 bends sharply at the end of the electric wire fixture 2, a tear may occur, In some cases, uniform tightening may not be possible, resulting in problems such as poor waterproofing and poor electrical insulation.
Further, there is a problem that the waterproof effect is further deteriorated when a plurality of electric wires are collectively processed.

To solve these problems, FIG.
As shown in (a), a method has been developed in which a plurality of cuts 7 are provided in the end portion of the electric wire fixture 2 and the electric wire 6 is fixed as shown in FIG. This method avoids the sharp bend of the shrink tube at the end of the wire fixture 2 as shown in (b) and is very effective for uniform tightening. When an electric wire having a different thickness is connected due to a clearance, there is a problem that the electric wire tightening force of the shrinkable tube 5 becomes poor and the electrical characteristics (insulation and waterproof, airtightness, tracking resistance) are deteriorated. Also,
There are problems that the electric wires are scattered during and after the processing of a plurality of electric wires, making it difficult to work, the binding force is weak, and the electrical connection stability is poor.

Therefore, in order to improve the electric characteristics and the binding force of the electric wires in the case of a plurality of electric wires, the following measures are taken. FIG. 11 shows the first method, in which the shrinkable tube is treated and then treated with the insulating and waterproof tape 8. In this method, the tape 8 can be easily obtained and is simple, but the workability is poor (long time, large variation) and the skill level is required. In addition, there is a problem in electrical characteristics (insulation, waterproofing, airtightness, variation, tracking resistance), and there is a problem in that the tape deteriorates and the cost increases.

The second method is a method of treating the gap with an insulating putty 9 after the contraction tube treatment. According to this method, the workability of filling the insulating putty 9 is poor, the airtightness and weather resistance of the putty are poor, and the binding force of the electric wire is weak. Further, there is a problem that the insulating putty 9 flows out during long-term aging.

The third method is a method in which, as shown in FIG. 12, a shrinkable tube is processed and then an insulating putty and a waterproof tape are combined and processed. This method has better characteristics than the first and second methods, but has poor workability, and has problems such as insufficient electric characteristics, large variations, and increased cost. Furthermore, as a fourth method, resin (thermosetting resin such as epoxy)
However, there is still a problem that workability is poor (variation is large, curing time is long, etc.).

[0008]

As described above, the above-mentioned conventional electric wire connection portion protection structure has advantages and disadvantages in each method, and there is a problem that waterproofness, workability, connection stability, etc. are poor. It was

The present invention seeks to realize a protective structure for an electric wire connecting portion which is improved in waterproofness, workability and connection stability.

[0010]

SUMMARY OF THE INVENTION In a protective structure for an electric wire connecting portion of the present invention, a contraction tube coated on the outside of the electric wire connecting part for protecting the electric wire connecting part and before the contracting tube contracts. In the protective structure of the electric wire connection portion, which is inserted into the shrinkable tube in a state where the electric wire is fixed, and the electric wire fixing tool holds the shrinkable tube after contraction of the shrinkable tube, the electric wire fixing tool is a shrinkable tube. Columnar or prismatic shape that can be inserted into a wire, and one or more through-holes for fixing the electric wire corresponding to the number of electric wires to be connected in the longitudinal direction inside thereof, or an electric wire to be connected to the surface thereof It is characterized by having one or two or more grooves for fixing electric wires corresponding to the number of. In addition, in addition to that, a ring-shaped projection is provided on the outer circumference of the electric wire fixture, the inner circumference of the through hole, or the inner circumference of the groove. By adopting this configuration, it is possible to obtain a protective structure for the electric wire connecting portion with improved waterproofness, workability, and stability of connection.

[0011]

After the electric wire is inserted or fitted into the electric wire fixture, the electric wire fixture is provided with one or more through holes or grooves in the longitudinal direction (axial direction) of the cylinder (including the Da cylinder) or the prism. ,
By performing the shrinkable tube treatment, it is possible to easily and quickly connect and insulate even a plurality of electric wires. This provides excellent insulation and electrical properties.

Further, by providing a ring-shaped projection made of an elastic body on the inner surface of the through hole or groove of the wire fixing device,
The projection adheres to the electric wire, and the insulation and moistureproof effect is improved. Further, since the protrusion also has a taper effect, the work of inserting the electric wire is facilitated and the work efficiency is improved. Furthermore, the binding force of the electric wires is also strengthened, and the stability of the electrical connection is also improved.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram showing an embodiment of the present invention.
FIG. 3 is an overall perspective view showing an open section, and (b) is a perspective view showing an electric wire fixture used in this embodiment. In the figure, 1
Reference numeral 0 is an electric wire fixture, 11 is a shrink tube, and 12, 12 'and 13 are electric wires.

As shown in FIG. 1 (b), the wire fixing device 10 penetrates the main body of the cylinder in the longitudinal direction (axial direction).
One through hole 14 is provided. And the through hole 14
The electric wires 12 and 12 'are inserted through the cable as shown in FIG. 3A, are connected to the other electric wire 13 at the portion A, and the outer side thereof is tightly covered with the contraction tube 11. In this embodiment configured as described above, the electric wire fixture 10 is provided by the shrinkable tube 11.
Since the electric wires 12, 12 'and 13 are tightly bound to each other through or through, the waterproof and moisture proof properties are improved, the deterioration of electric characteristics is prevented, and the binding force of the electric wires is strengthened to improve the stability of connection.

FIG. 2 is a diagram showing another embodiment of the present invention.
(A) and (b) are the whole perspective views which opened and showed a part,
(C) is a perspective view showing an electric wire fixture similar to this embodiment. In the electric wire fixture 10 shown in FIG. 1C, two grooves 15 are provided in the longitudinal direction (axial direction) of the main body of the cylinder. In the embodiment shown in (a), the electric wires 12 and 12 'are inserted into the groove 15 of the electric wire fixture 10 and connected to the other electric wire 13 at the portion A, and the outer side of the electric wire 12 and 12' is connected to the shrinkable tube 1.
It is tightly covered by 1. In the embodiment shown in FIG. 3B, the electric wires 12 and 12 'are inserted into the groove 15 of the electric wire fixture 10 and their ends are connected to each other.
Then, the cap 16 and the wire fixing device 10 are tightly covered with the shrink tube 11.

In the present embodiment thus constructed, the groove 15 of the wire fixing device 10 can be elastically deformed, so that the wire 1
Adhesion with 1, 11 'is good, and therefore waterproof and moistureproof properties are improved, and deterioration of electrical characteristics can be prevented. In addition, the binding force of the electric wire by the shrinkable tube is strong, and the connection stability is improved.

In the embodiment described above, the wire fixture 10
It is also possible to use an electric wire fixture as shown in FIGS. The electric wire fixture 10 shown in FIG. 3 has two through holes 14 provided in the main body of a cylinder, and a ring-shaped protrusion 17 provided in the middle of the through hole 14 to improve the adhesion with the electric wire. is there. The electric wire fixture 10 shown in FIG.
In FIG. 3, a ring-shaped projection 18 is further provided on the outer periphery to improve the adhesion with the shrinkable tube.

The electric wire fixture 10 shown in FIGS.
Is one in which one, two or four through holes 14 are provided in the main body of the cylinder, and three ring-shaped projections 17 are provided in the middle of each through hole 14 to improve the adhesion with the electric wire. Note that FIG. 5D shows a state in which the shrink tube 11 is actually attached to the electric wire 12. In addition, the electric wire fixture 10 shown in FIG. 8 is one in which two through holes 14 are provided in the main body of a quadrangular prism, and three ring-shaped protrusions 17 are provided in each of the through holes 14.

The main body of the above wire fixing device 10 is a cylinder or a prism, and the cylinder includes a true cylinder, a Da cylinder, a semi-cylinder and a cloud cylinder, but the wire can be clamped most uniformly. A cylinder is good. The prisms include polygonal prisms including triangular prisms and quadrangular prisms, and are determined in consideration of the thickness and number of electric wires.

The size of the wire fixing device is determined in consideration of the outer diameter and the number of wires to be applied. Specifically, if the diameter or the major axis is less than 0.5 cm, the number of wires is limited. If it exceeds 30 cm, manufacturing becomes difficult, so 0.5
A range of ~ 30 cm is good. The length is determined in consideration of the type and strength of the applied wire, but if it is less than 0.5 cm, the moisture-proof effect and mechanical strength are poor, and if it exceeds 30 cm,
Since the manufacturing becomes difficult and the workability becomes poor, 0.5
About 30 cm is good.

Further, the through hole portion of the electric wire fixture may have any shape as long as it is suitable for the electric wire to be applied.
There are half circles. The size of the through hole is determined from the outer diameter of the applied wire in consideration of moisture resistance, work efficiency, etc. Specifically, if there is no ring-shaped projection, the size of the wire is 40 % Or less, it takes a long time to insert an electric wire, resulting in poor work efficiency. When it exceeds 100%, a gap is formed between the electric wire and the electric wire fixture, resulting in poor moisture resistance.
It is desirable to set it to 0%. When a ring-shaped protrusion is provided in the through hole, the ease of inserting the wire is mainly determined by the inner diameter of the ring-shaped protrusion. Therefore, the inner diameter of the through hole is larger than the inner diameter of the ring-shaped protrusion and up to about 300%. good. Also, the number of through holes is not particularly limited.

Further, the groove of the electric wire fixture includes a cross-sectional shape of a semicircle, a double circle, a V shape, a U shape, etc., and its size,
The depth is determined in consideration of the moisture-proof work efficiency and the like in relation to the shape and outer diameter of the applied electric wire. Moreover, the number is not particularly limited. Further, protrusions corresponding to the ring-shaped protrusions shown in FIGS. 3 and 4 may be provided in the groove, and the shape, size, number, etc. thereof are determined in consideration of moisture resistance, workability, etc. It

The material of the wire fixing device is not particularly limited, but specifically, the following materials (1) to (3) are used. The material of the projection of the through hole or groove is not particularly limited, but an elastic body is preferable in consideration of the waterproof effect and the like. (1) Elastic body (rubber): natural rubber, EPR (ethylene propylene rubber), CR (chloroprene rubber), SB
R (styrene butadiene rubber), SBS (styrene
Butadiene / styrene block copolymer), SIS
(Styrene / isoprene / styrene block copolymer), BR (butadiene rubber), silicone rubber,
Fluoro rubber, acrylic rubber, etc. (2) Resin: urethane, vinyl chloride, acrylic, styrene, polycarbonate, ABS, polyester, polypropylene, polyacetal, epoxy, phenol, melamine, etc. (3) Filler: carbon, white carbon, calcium carbonate, titanium oxide, antioxidant, UV inhibitors, diluents, etc.

Further, these materials can be used, for example, in the following (1) to
It is also possible to use them in combination as in (3). (1) Outside: Resin Inside: Rubber (2) Outside: Hard Rubber Inside: Soft Rubber (3) Outside: Ceramic Inside: Rubber

The manufacturing method is as follows:
By die molding and shaving. Is the protrusion the same as the main body,
Alternatively, an O-ring or the like may be embedded.

Next, a practical example will be described. First, the electric wire fixture of the present invention is prepared by using a rubber raw material containing EPDM as a main component.
Molding was performed under the conditions of 70 ° C. × 5 minutes × 50 kg / cm ² . Using this electric wire fixture and a shrink tube (PST8407: manufactured by Sumitomo 3M Ltd.), a high-voltage draw-down line cross-linked polyethylene insulated electric wire (PDC: Pole transformer drop wire cros)
A two-core wire branch of slinked polyethylene) was implemented. After that, the connection portion was submerged, and the insulation resistance between the electric wire conductor and water was measured with an insulation resistance meter under the condition of DC 1000V. In addition, air pressure was applied from the end of the wire connection portion, and the air leak generation pressure was measured to examine the airtight property.

As a comparative example, the case of using a waterproof tape and the case of using both a waterproof tape and an insulating putty are shown. The evaluation results are shown in Table 1, and in the present invention, far better results are obtained in both the waterproof insulation property and the airtight property, as compared with the conventional products treated with the waterproof tape and the products treated with the insulating putty + the waterproof tape. .. In the present invention, the workability is better than the processing of the insulating putty and the waterproof tape, because the insulating putty and the waterproof tape are not processed.

[0028]

[Table 1]

[0029]

According to the present invention, excellent electric connectivity, electrical insulation, waterproofness, airtightness, tracking resistance and workability can be obtained in electric wire connection using a shrinkable tube. Moreover, when a plurality of electric wires are used, the binding force of the electric wires becomes strong, and as a result, the stability of electric connection is significantly improved.

[Brief description of drawings]

1A and 1B are views showing an embodiment of the present invention, in which FIG. 1A is an overall perspective view with a part cut open, and FIG. 1B is a perspective view showing an electric wire fixture used in this embodiment. ..

2A and 2B are views showing another embodiment of the present invention, in which FIGS. 2A and 2B are perspective views showing a whole part, and FIG. 2C is a wire fixing device used in this embodiment. It is a perspective view showing.

3A and 3B are views showing another example of an electric wire fixture used in the present invention, FIG. 3A being a perspective view and FIG. 3B being a partially cutaway perspective view.

4A and 4B are views showing another example of an electric wire fixture used in the present invention, in which FIG. 4A is a perspective view and FIG. 4B is a partially cutaway perspective view.

5A and 5B are views showing another example of an electric wire fixture used in the present invention, in which FIG. 5A is a front view, FIG. 5B is a sectional view taken along line bb in FIG. 5A, and FIG. Is a perspective view showing an open view of
(D) is a figure which shows a use condition.

6A and 6B are views showing another example of the electric wire fixture used in the present invention, in which FIG. 6A is a front view, FIG. 6B is a sectional view taken along line bb in FIG. 6A, and FIG. It is the perspective view which cut open and showed.

7A and 7B are views showing another example of the electric wire fixture used in the present invention, in which FIG. 7A is a front view, FIG. 7B is a sectional view taken along line bb of FIG. 7A, and FIG. It is the perspective view which cut open and showed.

8A and 8B are views showing another example of the electric wire fixture used in the present invention, in which FIG. 8A is a front view, FIG. 8B is a sectional view taken along line bb in FIG. 8A, and FIG. It is the perspective view which cut open and showed.

FIG. 9 is a diagram for explaining a conventional cable connection processing method using a shrinkable tube.

FIG. 10 is a diagram for explaining a method obtained by improving the method of FIG.

FIG. 11 is a view showing a conventional cable connection structure subjected to tape processing.

FIG. 12 is a diagram showing a cable connection structure in which a conventional insulating putty and tape treatment are used together.

[Explanation of symbols]

 10 ... Electric wire fixing tool 11 ... Shrink tube 12, 12 ', 13 ... Electric wire 14 ... Through hole 15 ... Groove 16 ... Cap 17, 18 ... Ring-shaped projection

Claims (2)

[Claims] 1. A contraction tube that covers the outside of the contraction tube to protect the connection part of the electric wire, and the contraction tube is inserted inside the contraction tube with the electric wire fixed before the contraction tube contracts. In a protective structure of an electric wire connecting portion including an electric wire fixing device that holds the contraction tube after contraction, the electric wire fixing device is a columnar shape or a prismatic shape that can be inserted into the contraction tube, and a longitudinal direction inside thereof. In addition, one or two or more through holes for fixing electric wires corresponding to the number of electric wires to be connected or one or more electric wire fixing grooves corresponding to the number of electric wires to be connected are provided on the surface thereof. Features a protective structure for electric wire connections. 2. The protective structure for an electric wire connecting portion according to claim 1, wherein a ring-shaped protrusion is provided on the outer circumference of the electric wire fixture, the inner circumference of the through hole, or the inner circumference of the groove.