Patent ID: 7652592

Claim:
A transmission device for transmitting data in an installation for working fluids contained underground, the installation comprising a cavity defined in an underground formation and extending to the surface of the ground, and at least one electrically conductive tubular element having a first point at the surface of the ground and a second point within the cavity, the transmission device comprising: a single-strand smooth cable for supporting an action and/or measurement assembly, said cable having a breaking strength greater than 300 daN, being made of an electrically conductive material, and being disposed in the tubular element between the first point and the second point, wherein a surface of said cable is electrically insulated, at least in part, from the tubular element; transmitter means for transmitting an electrical and/or electromagnetic signal, said transmitter means being situated in a vicinity of one or both of the first point and the second point, said transmitter means having: a first electrical contact point with the tubular element; and a second electrical contact point with said cable, said second electrical contact point of said transmitter means being electrically separated from said first electrical contact point of said transmitter means such that said transmitter means can apply a voltage between said first electrical contact point of said transmitter means and said second electrical contact point of said transmitter means; and receiver means for receiving the electrical and/or electromagnetic signal, said receiver means being situated in a vicinity of the other one or both of the first point and the second point, said receiver means having: a first electrical contact point with the tubular element; and a second electrical contact point with said cable, said second electrical contact point of said receiver means being electrically separated from said first electrical contact point of said receiver means such that said receiver means can detect a voltage between said first electrical contact point of said receiver means and said second electrical contact point of said receiver means, wherein said cable is a portion of a loop for conveying the electrical and/or electromagnetic signal between said transmitter means and said receiver means.