Pressure switch using Piezoelectric Crystal

grabcad

This model features a minimal number of components, making it unique, simple, and highly effective. Inside the vacuum cylinder, a diaphragm contacts a piezoelectric crystal; when pressure increases, the diaphragm compresses the crystal. This action induces charge displacement on the crystal's surfaces, generating an electric charge. The deflection can be detected by measuring the resulting potential difference or change in capacitance between the crystal and a fixed plate using a strain gauge attached to the diaphragm. The output is a voltage proportional to the applied pressure (0.6mV/kPa sensitivity). At just 0.33 grams, measuring 11.6 x 7 x 7 mm, this device has four components and includes automated calibration. Its cost-effectiveness, ease of manufacture, and user-friendliness make it an attractive choice.