Pressure measuring device - comprising a deformable substrate with screen printed thick film resistors forming an extensometer

摘要

Pressure measuring device comprises a deformable substrate submitted to the pressure to be measured, onto which is applied a resistive extensometer, and an electrical circuit which measures the pressure by compensating the resistance variations of the resistors as a function of the deformation of the substrate. Specifically, the extensometer is formed using thick film resistor applied by screen printing onto the substrate on one or both faces and in positions sensitive to the anticipated deformations. Suitable thick film resistive mixts. may contain =1 of the following resistive components: RuO2, IrO2, TlO2, Bi2RuO7, Pb2Ru2O7, Au, Pt, Pd and their alloys in a dielectric matrix such as a borosilicate, aluminosilicate, lead borosilicate, lead silicate or similar glass. The resistors show a high sensitivity to deformation and a very good temp. stability and a perfect thermal and mechanical adaptability between resistors and substrate.