Electric oil level indicator for engine - has heating element adjacent to thermocouple, whose temp. depends on oil level and which supplies operational amplifier linked to dashboard

摘要

The level of oil in a motor vehicle engine is determined by a heated element which is cooled when immersed in the oil. Measurement is made whether or not the engine is running. On the inside of an engine crankcase (1) is fixed a cylindrical casing (2) with a longitudinal slot in the lower surface (3) and two openings (6) in the upper surface (4). A heating element (8) contained within thi casing heats a thermocouple element (9) connected via conductors (12, 13) to the two inputs of an operational amplifier. A second amplifier drives a relay driver transistor to operate an indicator lamp on the dashboard when oil level is low.