Connecting head for connecting a cable and a downhole tool and associated intervention device

An intervention device in a fluid exploitation well in the subsoil comprising:

• an intervention and/or measuring tool intended to be lowered into the well,
• a cable for deploying the tool in the well, the cable being electrically connected to the tool, the cable having a smooth outer surface and comprising:
• a substantially cylindrical central conductor;
• an outer sheath applied on the entire periphery of the central conductor, the outer sheath advantageously including a polymer matrix;
• a transmission and control module for the tool;
• and
• a connecting head comprising:
• an upper portion for attaching and connecting to the cable;
• and
• a lower attaching portion for electrically connecting to a control and transmission module of the tool,
• the head comprising a hollow outer enclosure and a mechanical connection assembly received in the hollow outer enclosure, the mechanical connection assembly comprising:
• an attaching member;
• a liner defining an inner lumen to receive the attaching member and the lower end of the cable, the attaching member being able to grip the cable in the liner;
• wherein the connecting head defines a first downhole electrical path able to extend from a lower segment of the cable to a first connector of the control and transmission module, the first downhole electrical path being completely electrically insulated from the outer enclosure
• wherein the mechanical connection assembly comprises an electrically insulating sleeve electrically insulating the attaching member and the liner from the enclosure, and
• wherein the lower segment of the cable is gripped in the lumen between the attaching member and the liner, at least the central conductor of the cable being electrically connected to the first electrical path.