Gear Speed Sensor
A gear speed sensor consists of a sensor-head and a ferromagnetic gear with module 0.5. The sensor-heads are available in two versions: with a flat ribbon cable or as an sensor-chip that is suitable for surface-mount assembly. POSIC offers several standard gears, but you can use your own gear as long as it is made of ferromagnetic steel and has teeth with module 0.5. Module 0. 4 - 0.6 is feasible, module 0.5 is ideal.
POSIC is a Swiss company and delivers its inductive encoder kits worldwide.