Patent ID: 6269695
Filing Date: 2001-08-07
Classification: G01F,H01C

Abstract:
In a system for measuring the level of a liquid in a container having a volume/depth relationship, an analog liquid level sensor comprising:a support structure adapted to be received and retained within the container;a pair of electrically spaced terminals;a printed circuit formed on the support structure and electrically coupled between the terminals and having an effective resistance which varies at different positions on the printed circuit between the terminals wherein the printed circuit includes a resistor pattern and a metallization pattern having metallized graduations formed on opposite sides of the support structure for reduced electrical noise characteristics and improved hysteresis; anda float assembly connected to the support structure to reciprocate in a generally vertical direction relative to the support structure in response to the level of the liquid in the container, the float assembly including a hollow, buoyant housing and a contact assembly supported within the buoyant housing in fixed vertical relationship thereto for making electrical connection with the graduations of the metallization pattern on opposite sides of the support structure for changing the effective resistance of the printed circuit between the terminals, the terminals providing an electrical signal which is a function of the generally vertical position of the contact assembly along the support structure, and wherein the sensor has a resistance-to-float-displacement profile matched to the volume/depth relationship of the container.