Signal transmission device for towing vehicle

A signal transmission device for connection between a first electrical connector disposed at a truck-tractor of a towing vehicle and a second electrical connector disposed at a trailer of the towing vehicle for transmission of electric signals, the signal transmission device comprising:

• first and second magnetic holders for attaching the truck-tractor and the trailer respectively;
• a third electrical connector mounted to the first magnetic holder for connecting the first electrical connector;
• a fourth electrical connector mounted to the second magnetic holder for connecting the second electrical connector;
• a stretchable coil tube;
• and
• a cable spirally inserted through the stretchable coil tube and provided with two ends electrically connected with the third and fourth electrical connectors respectively,
• wherein each of the third and fourth electrical connectors comprises a connecting head connected to one of the two ends of the cable, and an adapter having an end connected to the connecting head, and an opposite end for connecting one of the first and second electrical connectors.

A signal transmission device for use in a towing vehicle, comprising:

• a magnetic holder;
• an electrical connector mounted to the magnetic holder;
• a stretchable coil tube;
• and
• a cable spirally inserted through the stretchable coil tube and provided with an end electrically connected with the electrical connector,
• wherein the magnetic holder comprises magnetic base and a bracket mounted on the magnetic base to support the electrical connector,
• wherein the bracket comprises a plurality of connection members pivoted to one another;
• at least one of the connection members is pivoted or fastened to the magnetic base and another one of the connection members holds the electrical connector.

A signal transmission device for use in a towing vehicle, comprising:

• a magnetic holder;
• an electrical connector mounted to the magnetic holder;
• a stretchable coil tube;
• and
• a cable spirally inserted through the stretchable coil tube and provided with an end electrically connected with the electrical connecter,
• wherein the electrical connector comprises a connecting head connected to the end of the cable, and an adapter having an end connected to the connecting head, and an opposite end adapted for connecting an external electrical connector.