CONTACTLESS POSITION SENSOR AND CONTACTLESS POSITION SENSOR SYSTEM

摘要

The invention relates to an improved contactless position sensor and a system incorporating same. Such a contactless position sensor comprises at least two sensor coils each comprising a magnetic permeable core and windings defining a coil axis. The at least two sensor coils are arranged with the coil axes essentially in parallel to each other. An electrical circuit of the sensor drives a predetermined alternating current within each of the at least two sensor coils and determines a high frequency voltage component of a voltage across each of the at least two sensor coils. The predetermined alternating current includes a low frequency current component, and a high frequency current component. The electrical circuit detects the position of a ferromagnetic target by subtracting from each other amplitude levels of the high frequency voltage components of two of the determined voltages and by comparing the subtraction result to a pre-determined reference pattern.