Hall-effect sensor placed in flowmeter to measure fuel flow rate

摘要

A pick-up assembly for use in a liquid dispensing system utilizes a Hall-effect sensor integrated within a flowmeter to provide a measure of the rotational velocity of the rotor and hence the flow rate of liquid being transmitted through the liquid line. The rotor is modified to include at least one recessed area defined in its outer surface and which exhibits magnetic properties. The Hall-effect sensor includes a first and second Hall-effect element each generating a respective channel signal that is representative of the rotational velocity of the rotor. The Hall-effect sensor is suitably arranged with respect to the rotor so as to enable each one of the recessed areas to exert a characteristic magnetic influence upon the Hall-effect sensor during shaft rotation. The variable magnetic flux experienced by the Hall-effect sensor appears as a corresponding variation in the voltage signal generated by the sensor. The rate of generation of such magnetic field variations is representative of the rotational velocity of the rotor.