1. Field of the Invention
This invention relates to a crimping terminal for connection between electric cables, and more particularly, the invention relates to a crimping terminal that can prevent moisture from coming into clearances between core wires in the electric cables.
2. Description of the Related Art
Prior art electric cables that extend from electric devices easily can be coupled to or disconnected from each other by attaching a connector to each of the electric cables and coupling and disconnecting the connectors. Some prior art connectors are constructed to prevent the intrusion of water. For example, as shown in FIG. 5, waterproof connectors 1 and 2 are attached to the electric cables C. The FIG. 5 assembly also includes a non-waterproof connector 3 that is attached to an electric cable C Additionally, a so-called round terminal 4 or the like is attached to an electric cable C to perform direct screw connection. These connections involve different handlings due to differently designed wiring paths and costs for the respective electric cables C.
The electric cable C conventionally is constructed by twisting a plurality of soft copper wires xe2x80x9cexe2x80x9d and covering the wires with a vinyl chloride sheath, as shown in FIG. 6. The sheath functions as an electrical insulation. However, water readily enters an end of the electric cable and flows downstream due to capillary phenomenon. For example, as shown in FIG. 7, an insulation barrel I is crimped on an outer surface of the electric cable C and a wire barrel W is crimped on core wires xe2x80x9cexe2x80x9d the sheath of which is stripped at an end of the electric cable C. Consequently, water enters an end of the electric cable C and reaches the waterproof type connectors 1 and 2. In the worst case, this may cause an electrical short-circuit. The non-waterproof connector 3 has a similar terminal (not shown) that merely is crimped on the electric cable C. Thus, the same water-related accidents will occur in the electric cable.
Accordingly, an object of the present invention is to obtain a waterproof function of a mating member to which an electric cable is connected and to enhance reliability of connection between the electric cables by preventing water from entering the electric cables.
The subject invention is directed to a crimping terminal for connection between electric cables. The crimping terminal includes at least two crimping portions each of which is crimped on an end of an electric cable. The electric cables are connected to each other by crimping the crimping portions, thereby extending the electrically conductive path. The crimping terminal is characterized by a liquid-tight solid portion between the crimping portions.
The solid liquid-tight body between the crimping portions of the crimping terminal is different from a conventional tubular terminal for connection. Water cannot enter the crimping terminal and the body made of a conductive material can electrically connect the electric cables. Consequently, the crimping terminal can interrupt water, which enters an electric cable at an up stream-side and flows in the cable. The crimping terminal also can prevent water from further flowing in an electric cable at a down stream-side.
The invention also is directed to a crimping terminal as described above, but further comprising a tubular member made of a thermal-shrinkable material. The tubular member is adapted to cover the outer surfaces of the crimping portions in a liquid-tight manner and extends to cover the ends of the electric cables adjacent the crimping portions. A material is applied on an inner surface of the tubular member so that the inner surface comes into contact with outer surfaces of the crimping terminal and electric cables in a liquid-tight manner
In this embodiment of the invention, it is possible to bring the tubular member into close contact with the outer surfaces of the crimping portions and ends of the electric cables by heating the tubular member with a dryer or the like. Accordingly, it is possible to prevent the water, which is interrupted in the electric cable, from coming out onto the outer surfaces of crimping portions and entering an electric cable at a down stream side from an electric cable at an up stream side