THICKNESS MEASURING DEVICE USING EDDY CURRENTS AND CORRESPONDING MEASUREMENT METHOD

A thickness measuring device (1) for measuring thickness of a non-magnetic conductive object (5), entails: an eddy-current sensor stage (2), having a coil element (4) to be arranged at a given distance (d) from the object (5) and an excitation module (2a), which provides an excitation signal (Sin) to the coil element (4) in order to generate eddy currents; and a processing stage (40), which processes detection signals (Sd) provided by the coil element (4) as a function of the magnetic field generated by the eddy currents in order to estimate a thickness (c) of the object (5). The processing stage (40) estimates the thickness (c) as a function of a peak frequency (f_min) associated with an impedance variation occurring when the coil element (4) is arranged near the object (5) as compared to when the coil element (4) is placed in air and as a function of a characteristic variable (α_0) associated with the coil element (4) and with the object (5). In particular, the processing stage (40) implements an optimization module (16), to calculate an optimized value for the characteristic variable (α_0) and a thickness estimation module (18), to estimate a corresponding value of the thickness (c).