Electric connector and cable

1. An electrical connector comprising:

a conductor exposed from a covering;

a connection portion of the conductor connected to a connection portion of a terminal;

a connector housing receiving the terminal;

an impedance control means fixed on the connection portions of the conductor and the terminal; and

a second covering that covers a part of the covering, the impedance control means and a part of the connector housing, wherein

the impedance control means is a foam resin controlling an impedance in terms of a foam ratio that is selected so that an impedance of the connection portions substantially match the impedance of the covering of the conductor.

2. The electrical connector according to claim 1 ,

wherein the foam resin functions as a capacitive capacitor.

3. The electrical connector according to claim 1 ,

wherein respective connection portions of the conductor and the terminal are located in a cavity of the connector housing,

wherein the connector housing is made of a foamed resin.

4. The electrical connector according to claim 1 ,

wherein the foam ratio is greater than 0% and 80% or less.

5. The electrical connector according to claim 1 ,

wherein the foam resin has strength to maintain a structure thereof.

6. An electrical connector according to claim 1 , wherein the foam resin fills a surrounding space defined by the connection portions and the second covering.

7. A method of fabricating an electrical connector, comprising:

connecting a connection portion of a terminal and a connection portion of a conductor exposed from a covering to each other;

receiving the terminal in a connector housing;

fixing impedance control means on the connection portions of the conductor and the terminal; and

covering a part of the covering, the impedance control means and a part of the connector housing with a second covering;

wherein the impedance control means is a foam resin controlling an impedance in terms of a foam ratio that is selected so that an impedance of the connection portions substantially match the impedance of the covering of the conductor.

8. The method of fabricating an electrical connector according to claim 7 ,

wherein the foam resin is controlled to be approximate in impedance to the covering.

9. The method of fabricating an electrical connector according to claim 7 ,

wherein the foam resin is molded to cover respective connection portions.

10. The method of fabricating an electrical connector according to claim 7 ,

wherein the foam resin is formed into a predetermined shape to be fitted to respective connection portions.

11. The method of fabricating an electrical connector according to claim 7 ,

wherein the foam resin is formed as a tape to be wound around respective connection portions.

12. An electrical connector comprising:

a cable comprising:

an electrical wire including a conductor exposed from a first covering;

a drain wire arrayed parallel to the electric wire; and

a jacket holding the electric wire and the drain wire;

a connection terminal having a connection portion connected to an end of the conductor;

an earth terminal having a connection portion connected to an end of the drain wire;

a connector housing receiving the connection terminal and the earth terminal; and

a second covering located around a foam resin, wherein

the foam resin is configured to control an impedance in terms of a foam ratio that is selected so that an impedance of the connection portion substantially matches an impedance of a the first covering.

13. A cable comprising:

an electric wire having a conductor exposed from a covering;

a connection portion of the electric wire connected to a connection portion of a terminal;

a connector housing receiving the terminal;

a foam element fixed on the connection portions of the electric wire and the terminal; and

a second covering that covers a part of the covering, the foam element and a part of the connector housing,

wherein the foam element is a foam resin controlling an impedance in terms of a foam ratio that is selected so that an impedance of the connection portions substantially match the impedance of the covering of the electric wire.

14. A connector for a signal transmission cable, comprising:

a connector housing;

a terminal fixed to the connector housing;

a cable conductor exposed from a covering and electrically connected to the terminal by welding within the connector housing;

an impedance control means fixed on a connection of the terminal and the cable conductor; and

a second covering that covers a part of the covering, the impedance control means and a part of the connector housing,

wherein impedance control means is a foam resin controlling an impedance in terms of a foam ratio that is selected so that an impedance of the connection of the terminal and the cable conductor substantially match the impedance of the covering of the cable conductor.

15. The connector for a signal transmission cable according to claim 14 ,

wherein the connection portions include a molten alloy layer.

16. The method of fabricating a connector for a signal transmission cable, comprising:

welding a terminal and a cable conductor having a covering to make a connection portion;

inserting the terminal in a housing;

preparing a foamable resin;

locating connection portions of the terminal and the cable conductor in a die;

feeding the foamable resin into the die for extrusion to cover the connection portion with a foam element;

forming a second covering that covers a part of the covering, the foamable resin and a part of the housing,

wherein foamable resin is configured to control an impedance in terms of a foam ratio that is selected so that an impedance of the connection portions of the terminal and the cable conductor substantially match the impedance of the covering of the cable conductor.

17. A method of fabricating a connector for a signal transmission cable, comprising:

welding a terminal and a cable conductor to each other for connection;

forming a pair of foam resin covering members preliminarily formed into shapes which conform to an upper half shape and a lower half shape of connection portions of the terminal and the cable conductor;

fitting said pair of covering members around the connection portions of the terminal and the cable conductor; and

molding a resin for a connector housing around the terminal, the pair of foam resin covering members, and the cable conductor exposed from a covering, thus to form the connector housing in a predetermined shape,

wherein the foam resin configured to control an impedance in terms of a foam ratio that is selected so that an impedance of the connection of the terminal and the cable conductor substantially match the impedance of the pair of covering members.

18. The method of fabricating a connector for a signal transmission cable, according to claim 17 , wherein the foam resin has a predetermined foam ratio selected to substantially match the impedance of the connection portions with a covering of the cable conductor.

19. A method of fabricating a connector for a signal transmission cable, comprising:

welding a terminal and a cable conductor for connection;

preparing a foam resin tape;

winding the foam resin tape a predetermined number of times around connection portions of the terminal and the cable conductor to cover the connection portions;

molding a resin for a connector housing around the terminal, the foam resin tape, and the cable conductor exposed from a covering, thus to form a connector housing in a predetermined shape,

wherein the foam resin tape is configured to control an impedance in terms of a foam ratio that is selected so that an impedance of the connection of the terminal and the cable conductor substantially match the impedance of the covering of the conductor.