Capacitive measuring transducer

Claim 1

A capacitive transducer for measuring the level of liquid in a container, said transducer being connected to the end of an electrically insulated cable adapted for suspension in the container and said transducer comprising a circuit board carrying associated electronic circuitry, said circuitry being connected to the conductors at one end of said cable; a metal tube having one end disposed in the proximity of said one end of the cable, said circuit board being disposed with the metal tube so that said metal tube provides mechanical protection and electrical shielding for said electronic circuitry where at the end of the metal tube in the proximity of the cable, the metal tube is closed by a metal cover through which pass the conductors of the cable and where the metal tube is covered on the inside and on the outside with an insulating layer; a hollow insulating member connected at one end thereof to the end of said metal tube remote from the cable; an electrode disposed at the end of the hollow insulating member remote from the metal tube; a wire extending through said hollow insulating member for connecting said electrode to said electronic circuitry; said metal tube, said hollow insulating member and said electrode comprising a rigid unit which surrounds said circuit board with its associated electronic circuitry and the wire extending between the circuitry and the electrode; and a continuous, homogeneous sheathing of insulating material which covers the external surfaces of the rigid unit and said one end of the cable so that a smooth covering is formed over the entirety of the transducer and said one end of the cable.