Water content measuring appts. for vehicle braking fluid - has capacitive sensor using brake fluid as dielectric and negative temp. coefficient compensation resistor

摘要

The arrangement has a measurement sensor consisting of two measurement rings mounted in plastic and together forming a capacitor which uses the brake fluid as a dielectric. The variation of the dielectric constant caused by variation in the water content is measured. The variation of the dielectric constant with temp. is compensated by a negative temp. coefficient resistor. The evaluation electronics can be a window discriminator, digital display or control processor. ADVANTAGE - Measures braking fluid water content directly in fluid reservoir.