Fuel level continuous indication for vehicles - using high temp. coefficient rod shaped resistor and external series indicator

摘要

The device is for monitoring the fuel level in a vehicle fuel tank using a resistor with a high temp. coefficient inside the tank and a series indicator device outside the tank is improved to provide a continuous indication. The design also enables reduced mounting cost to be achieved. Conventional arrangements use several thermal resistors positioned at various heights in the tank which illuminate lamps when the fuel falls below their individual heights, thus giving a discontinuous indication. A rod-shaped PTC resistor or "cold conductor" (1) is mounted vertically inside the tank held in a screw mounting (3) by means of which it is inserted in or removed from the floor (4) of the tank. As the fuel (8) level falls the resistor impendance changes and is indicated on a meter (5).