Linear transducers

An electrical linear transducer comprising:

• a tubular former having an axial extent, a plurality of windings on said former, said windings including only series connected windings and no primary and extending along the axial extent of said former, there being at least three windings, each of said windings having the same number of turns and an axial length with all of said winding axial lengths being equal and all adjacent windings being in non-overlapping side-by-side relationship on said former, said windings being wound so that immediately adjacent windings are wound in opposite directions;
• a cylindrical core member having an axial extent equal to the axial extent of each winding and positioned inside said tubular former to be movable axially of said former within said windings, said core member moving within said former causing the inductance of the transducer to vary from a maximum value when said core member is positioned entirely and coextensively within one of said windings to a minimum when said core member is positioned with one-half of said core member in one winding and one-half of said core member in a winding located immediately adjacent to said one winding so the inductance of the transducer varies cyclically as said core member moves axially through said former with the variation in inductance providing an indication of the extent of movement of said core member within said former.