Sensor for use in a fluid transfer system

摘要

A sensor for measuring the amount of a fluid such as electrostatically charged paint in a canister wherein part of the sensor moves within a cavity which is insulated from the paint. A body such as a piston moves linearly within the canister to dispense the paint from the canister. In two embodiments, the sensor is a non-contact sensor including a magnet which moves with the piston and creates a magnetic field in the cavity. A ferromagnetic device of the sensor moves linearly along a sensor element in the cavity in response to movement of the magnetic field created by the moving magnet. In another embodiment, the sensor includes an elongated pliable cable connected at one end thereof to the piston to move therewith. The opposite end of the cable is connected to a sensor element of the sensor such as a rotary encoder. Each sensor provides a signal to allow the metering of the paint entering or/and discharged from the canister.