Jitterless Pulse Generator Elements Using Amorphous Magnetostrictive Wires

Abstract

New jitterless pulse generator elements are presented using as-prepared amorphous magnetostrictive wires. These wires induce very sharp voltage pulses of ∼6V/cm² · Oe · turn at pick-up coils due to the large Barkhausen effect and of ∼6 V/cm³ · Oe between both ends of the wire due to the Matteucci effect against wire-axial ac fields of more than 0.1 Oe and of 0.01 Hz∼10 kHz. Jitter of pulse inducing phase is less than 1/10 that of Wiegand wires. These stable amorphous wires are suitable for applications to high-resolution rotary encoders for accurate speed sensing or position sensing in the fields of “mechatronics” such as power motors, industrial robots, automobiles, and industrial measurement instruments. Effects of etching and heat treatments on pulse induction and higher-harmonics generation are also investigated.