Linear displacement transducer utilizing an oscillator whose average period varies as a linear function of the displacement

摘要

A measuring system comprises a transducer producing a time varying function, a digital counter, and a reference oscillator to produce a direct digital measurement of a displacement. Axial displacement of a movable component of a variable inductor causes the average period of a self-contained oscillator to vary as a linear function of the measured displacement. A single coaxial cable provides the necessary electrical connections to the transducer. Linear components used in the variable inductor produce a linear output function derived from a complex combination of square and square-root functions. Deviations from true linearity are compensated. The device is particularly useful where precise, high resolution, displacement measurements are made over a relatively short range, or where such measurements are multiplexed for computer data storage and analysis.