초록 ▼

A single capacitor is used to measure the oil level in an engine or transmission and compensate the sensed capacitance for changes in dielectric constant. Measurements are made for two different running conditions, one giving a capacitance reading dependent only on dielectric constant and one giving

A single capacitor is used to measure the oil level in an engine or transmission and compensate the sensed capacitance for changes in dielectric constant. Measurements are made for two different running conditions, one giving a capacitance reading dependent only on dielectric constant and one giving a capacitance dependent on oil level as well as dielectric constant. The transmission application uses a capacitor that is fully immersed in oil when the engine is off and partly immersed when the engine is idling, so that both types of measurements can be obtained. The engine application uses a capacitor having an upper section spaced from a lower section. Only the lower section is immersed during engine idle to render dielectric constant information, while the upper section is partly immersed when the engine is off.

대표청구항 ▼

Means for measuring oil level in an automotive vehicle subject to change of oil level according to engine running conditions, comprising an oil reservoir containing oil the level of which is to be measured, a single capacitor in the reservoir positioned for immersion in said oil to a predictable amo

Means for measuring oil level in an automotive vehicle subject to change of oil level according to engine running conditions, comprising an oil reservoir containing oil the level of which is to be measured, a single capacitor in the reservoir positioned for immersion in said oil to a predictable amount during a reference measuring period and for immersion in said oil to a variable level during a level measuring period, and means controlled by engine running conditions for measuring the capacitances of said capacitor respectively during the reference and level measuring periods and for comparing the two capacitances to determine the level of oil in said reservoir.