Capacitive transducer for differential pressure measurement - achieves precise, linear characteristic with small parallel capacitances using nonlinear flexing region of centre electrode

摘要

A capacitive pressure transducer for differential pressure measurement contains a monolithic elastic deformation body centre electrode (1) consisting of a stiffening ring with a central plate spring and electrode carriers (5) on both sides. The centre electrode is equidistant from the fixed electrodes when the pressure is equal, the distance being approximate to the centre electrode thickness. Greater capacitive changes are achieved by leaving the linear region of the electrodes flexing function. The output of an electronic circuit corresp. to a defined relationship between the capacitances and geometry. USE/ADVANTAGE - For precise measurement of small pressure differences for measuring vol. flow in pipes at low equilibrium pressure. Large capacitance changes and a linear relationship are achieved with minimal parallel capacitances.