The Swiss miniature motor specialist maxon claims to have developed the world’s smallest inductive encoder. The 6mm-diameter Mile encoder delivers 64 pulses at up to 120,000 rpm, and is said to be immune from the effects of EMC, dust and oil.

Although ironless, eddy current-based inductive encoders have been used for a long time in large motors, maxon claims it is the first company to use them for micromotors. It says that it has invested heavily in developing the miniaturised encoders which it expects to be used in robots, medical equipment, and industrial applications in harsh environments.

The three-channel encoders have configurable index pulses, line drivers and integrated commutation outputs. Initially, maxon is using the encoders with its EC6 brushless DC motors, extending their length by just 1mm. Versions for other motors will follow.