Resonant vibrating structures with driving sensing means for noncontacting position and pick up sensing

摘要

A vibration type sensor can make a noncontacting measurement of position or pick up the passage of an object past a point. The sensor has a coil of wire placed on a vibrating structure. As an object with an attached magnet approaches the coil, an emf is induced in the coil indicating position. Alternatively, the magnet remains fixed with respect to the vibrating coil while a material of high magnetic permeability approaches the coil and magnet combination thereby perturbing the magnetic field and changing the induced emf. This method can be used to obtain a linear variation of sensor output with position or to enable the use of the device as a pickup sensor.