JPH0637575Y2 - Sealed wire connection terminal - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric wire connecting terminal used for connecting a covered electric wire, and a sealed electric wire connecting terminal capable of making a completely sealed connection without exposing the core wire of the connecting electric wire to the outside. It is a device.

[0002]

2. Description of the Related Art Normally, when a covered electric wire is connected to a terminal,
If a part of the core wire of the covered electric wire is exposed to the outside, there is a risk of electric leakage, which is not preferable. Therefore, the present applicant has previously proposed, in Japanese Utility Model Laid-Open No. 3-34060, a sealed electric wire connecting terminal capable of connecting a core wire of a connecting electric wire in a completely hermetically sealed state without exposing the core wire to the outside. According to this proposal, the core wire of the covered electric wire inserted and connected to the terminal is completely covered and sealed by a heat-shrinkable synthetic resin tube in a state of being crimped to the tubular portion of the terminal to ensure high watertightness. However, it has the following problems.

[0003]

That is, according to this prior art, the tip end side open end surface of the tubular portion of the wire connecting terminal into which the core wire of the covered electric wire to be connected is inserted is used to vertically close the synthetic resin tube. Since it is hermetically sealed by the membrane, the tip of the inserted core wire cannot come out from the open end of the tubular part by coming into contact with the closed membrane, and is housed only inside the tubular part. Therefore, at the time of connecting the electric wire, when the central portion of the cylindrical portion having a limited length is crimped, the bulging portion of the tip of the core wire cannot be formed over a sufficient length. If this bulge is small, the resistance against the pulling out direction of the wire will be weak, and a strong wire connection cannot be achieved.

In view of this, in the present invention, the heat-shrinkable resin tube is used to seal the distal end opening portion of the terminal tubular portion with a small space in front of the distal end opening portion of the tubular portion of the terminal. When crimping and connecting, the bulging part of the core wire tip can be formed with sufficient length over this space to enhance the resistance against the wire withdrawing direction, and thus to firmly connect the wire. The main purpose is to provide the electric wire connection terminal.

[0005]

In order to achieve the above object, in the wire connecting terminal according to the present invention, a metal terminal (1) having a wire connecting tube portion (1a) and the wire connecting tube are provided. Part (1a)
Small-diameter part (2a) that covers the inside of the wire
A synthetic resin tube (2) having a large-diameter portion (2b) for overcoating, and a heat-meltable resin layer (3) bonded to the entire inner peripheral surface of the tube (2), The tube (2) is formed of a heat-shrinkable resin material, the heat-meltable resin layer (3) is formed of a resin material that melts at a temperature equal to or lower than the heat-shrinkage temperature of the tube (2), and the small diameter portion ( 2a) is an electric wire connecting terminal formed by heat-shrinking the tube (2), from the upper edge or the left and right side edges of the front end surface of the tubular portion (1a) of the terminal (1) to the terminal tip ( Protruding piece of appropriate length toward 1b)
(1c) is extended, the tube (2) and the hot-melt resin layer (3) are extended to a position beyond the protruding piece (1c), and the extended portion (2c) is heat-shrinkable. And is closely attached to the body (1d) of the terminal (1).
It is structured to seal the tip side opening of the tubular portion (1a) with a space (4) between the a) and the tip of the protruding piece (1c), and the tube (2) is an inner layer. The structure including the heat-fusible resin layer (3) is formed of a transparent body which is transparent.

[0006]

In the electric wire connecting terminal constructed as described above, first, as shown in FIG. 3, the core wire (5b) of the electric wire (5) is inserted into the tubular portion (1a) of the terminal (1) at the inner part of the space (4). After inserting until it hits, the electric wire is joined by crimping the intermediate portion of the tubular portion (1a) with a crimping tool as shown in FIG. At this time, the core wire generated by crimping
The bulge at the tip of (5b) is formed in a wide range over the entire length of the space (4) from the crimping portion, and the bulge spreads radially as shown in Fig. 5, so the resistance against the pulling direction of the wire is remarkable. It is possible to increase the number and to firmly connect the electric wires. After connecting the covered electric wire (5) in this way, as shown in FIG. 6, the large diameter portion (2b) of the synthetic resin tube (2) is heated and shrunk by using a heating device such as a hot gun, and at the same time, the large diameter portion (2b) is shrunk. By melting the hot-melt resin layer (3) on the inner surface of the diameter portion, the large diameter portion (2b) is brought into close contact with the coating portion (5a) of the electric wire. As a result, the core wire portion from which the coating has been peeled off can be completely sealed.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments shown in FIGS. In this embodiment, a so-called flat-shaped connecting tip (1b) is formed in a circular shape with a round hole (1e), and a tubular portion (1a) is formed at the other end through a constricted body (1d). The present invention is applied to a round terminal. The metal terminal (1) is made of copper plate, the external heat-shrinkable tube (2) is made of resin such as nylon, and its inner surface is made of a resin material such as polyamide that melts at a temperature below the heat-shrinkage temperature of the tube (2). It has a double-tube shape in which the hot-melt resin layer (3) formed in (3) is laminated. The tube (2) is a concentric circular large and small tubular section (2
b) and (2a), and the small diameter portion (2a) is brought into close contact with the outer peripheral surface of the tubular portion (1a) of the terminal (1) by heat shrinkage. The large diameter part (2b) of the tube is in a state before heat shrinkage, and the covered electric wire (5)
The covering portion (5a) is set to a size that allows easy insertion.

Thus, a protruding piece (1c) of an appropriate length is extended from the upper edge of the front end surface of the tubular portion (1a) of the terminal (1) toward the terminal tip portion (1b). The tube (2) and the heat-meltable resin layer (3) are extended to a position beyond the protruding piece (1c), and the tip of the extended portion (2c) is heated and shrunk so that the terminal (1 ) Is closely attached to the flat torso (1d). This allows the tip opening surface of the tubular portion (1a) of the terminal (1) and the protruding piece (1
The front end side opening portion of the tubular portion (1a) is hermetically sealed with a space (4) between the tip and the tip of c). Also, the tube
(2) is formed of a transparent body that is transparent to the inside, including the inner layer of the heat-fusible resin layer (3), so that it is possible to see the inserted state or the crimped or compressed state of the wire. There is. In addition, if the tube (2) is lightly colored and the color is color-coded according to the size of the tubular portion, it can be conveniently used without making a mistake in the size.

In the present invention, the projecting piece (1c) may be projected from both left and right sides of the front end surface of the tubular portion (1a) as shown in FIG. Similarly, a space part (4) can be formed between the open end surface of the cylindrical part (1a) and the ends of the protruding pieces (1c) and (1c). If the tip ends of the left and right protruding pieces (1c) and (1c) are bent so as to be in contact with each other as shown in FIG. 8, the space (4) is formed by the thermal contraction of the tube (2). Can be achieved more reliably, and can also serve as a solid stopper when inserting an electric wire. Further, in addition to the wire connection terminal shown in the first embodiment, as shown in FIG. 9, the standing protrusion (1f) is cut and raised from the terminal body (1d) at the tip of the protruding piece (1c). In this case, the space (4) can be more surely formed by the heat shrinkage of the tube (2) as in the previous embodiment, and the space (4) acts as a solid stopper when the electric wire is inserted.

In the embodiments described above, the present invention is applied to a round terminal, but it is needless to say that the present invention can be applied to a bifurcated terminal or a terminal having a connecting portion of any other form. is there. In addition to the materials described above, the tube (2) may be a double layer of high temperature nylon and low temperature melting nylon, or high density polyethylene, and the heat melting resin layer (3 ) May be a hot melt adhesive. In this case, a material having good adhesiveness to polyvinyl chloride, which is generally used as a covering material for electric wires, is preferable.

Although the representative embodiment of the present invention has been described above, the present invention is not necessarily limited to the structure of the above-mentioned embodiment, and is within the scope of having the constituent features of the present invention and being effective. Of course, it can be implemented by appropriately changing it.

[0012]

Since the present invention is constructed as described above, the core wire of the covered electric wire connected to the terminal is completely sealed by the heat-shrinkable synthetic resin tube so that the water-tightness at the electric wire connecting portion is improved. In particular, in the present invention, when connecting the electric wire, when inserting the core of the electric wire into the terminal tube until it hits the inner part of the space and crimping the terminal tube, Since the space is formed between the tip opening surface of the portion and the tip of the protruding piece, the radial bulge of the tip portion of the core wire caused by crimping can be formed in a wide range from the crimping portion to the entire length of the space portion. As a result, the resistance against the pull-out direction of the wire is significantly increased, and the wire can be firmly connected, thus compensating for the sealed wire connection state that can withstand many years of use. There is an effect and the like.

[Brief description of drawings]

FIG. 1 is a perspective view showing only a metal terminal portion of an electric wire connection terminal according to the present invention.

FIG. 2 is a cross-sectional view showing a first embodiment of an electric wire connection terminal according to the present invention.

FIG. 3 is a cross-sectional view showing a first step in the process of connecting an electric wire to the electric wire connecting terminal shown in FIG.

FIG. 4 is a cross-sectional view showing a second stage of the electric wire connecting process.

FIG. 5 is a partial cross-sectional plan view of the tube shown in FIG. 4 with the upper portion of the tube removed.

FIG. 6 is a cross-sectional view showing the final stage of the electric wire connecting process.

FIG. 7 is a perspective view similar to FIG. 1, showing another embodiment of the present invention.

FIG. 8 is a perspective view similar to FIG. 1 showing still another embodiment of the present invention.

FIG. 9 is a perspective view similar to FIG. 1, showing another embodiment of the present invention.

[Explanation of symbols]

 (1) Metal terminal (1a) Metal terminal tube (1b) Metal terminal tip (1c) Metal terminal protruding piece (1d) Metal terminal body (2) Tube (2a) Tube small diameter section (2b) ) Large diameter part of the tube (2c) Extension part of the tube (3) Thermofusible resin layer (4) Space part (5) Wire (5a) Wire sheath (5b) Wire core wire

Claims (1)

[Scope of utility model registration request] 1. A metal terminal having a wire connection tube portion (1a)
(1) and a small-diameter portion (2a) for internally fitting and covering the electric wire connection tubular portion (1a)
And a large-diameter part for overcoating the covering part (5a) of the electric wire (5)
A synthetic resin tube (2) having (2b);
(2) consisting of a heat-meltable resin layer (3) bonded to the entire inner peripheral surface, the tube (2) is formed of a heat-shrinkable resin material,
The heat-fusible resin layer (3) is formed of a resin material that melts at a temperature not higher than the heat shrinkage temperature of the tube (2), and the small diameter portion (2a) is formed by heat shrinking the tube (2). In the wire connection terminal, the tube part of the terminal (1)
A protruding piece (1c) of an appropriate length is extended from the upper edge or the left and right side edges of the front end surface of (1a) toward the terminal tip portion (1b). The resin layer (3) is the protruding piece (1c)
It is formed by extending to a position beyond that, and the extension portion (2c) is heat-shrinked and closely adhered to the body portion (1d) of the terminal (1), thereby protruding from the cylindrical portion (1a) of the terminal (1). It has a structure that seals the opening on the tip side of the tubular part (1a) with a space (4) between it and the tip of the piece (1c), and the tube (2) has a heat-melting property of the inner layer. A sealed electric wire connection terminal formed of a transparent body including a resin layer (3).