Extra Distance Inductive Sensors Detect Presence of Metal Washers in Plastic Assemblies

A plastics manufacturer tests batches of control knobs for in-car audio systems before shipment to automotive assembly plants; each knob contains a small metal washer that occasionally becomes dislodged. A custom-built testing machine tests a tray of 70 knobs in a single cycle; long-distance inductive sensors, positioned directly below the knobs, confirm the presence of…