Multiparameter Oil Condition Sensor Based on the Tuning Fork Principle

For oil condition analyses in vehicles a micro sensor, now ready for series production, has been developed which is capable to measure the dynamic viscosity, specific density, permittivity, conductance, and temperature of the oil. For that purpose the resonant curve of a Tuning Fork Quartz Resonator is converted into the equivalent electrical impedance by means of an integrated ASIC and transmitted onto a microcontroller via a digital interface. The current oil condition (i. e. content of fuel, soot, water) is calculated by a multi-parametric analysis and transferred to the ECU of the vehicle. The received data is used substantially to prolong frequencies of oil changes and prevent vehicle downtime caused by wear.