Movement sensor with plate forming single turn coils

A movement sensor for sensing the movement of a moving part comprising:

• a magnetic circuit in the form of a horseshoe with two branches terminating in pole faces defining an air-gap;
• and
• an electric circuit comprising coil means defining a pair of single-turn coils connected in parallel between two connecting terminals, each branch of the magnetic circuit being surrounded by a said single turn coil respectively, and a ferro-magnetic element integral with the said moving part, one of said magnetic circuit and said element being magnetized for inducing a current in said single-turn coils by the magnetic flux variation caused by the movement in front of the pole faces, said coil means including a flat plate made from a conducting material, and forming the said single-turn coils, the plate having at least one aperture through which the ends of said branches pass so as to support said magnetic circuit and being connected to said connecting terminals, one of the connections passing between the said branches to provide both a common wire of the parallel connection and a common wire of the said single-turn coils and means for insulating said plate from said magnetic circuit.