Magnetostrictive torque sensor device, manufacturing method thereof, and vehicle steering apparatus

摘要

A magnetostrictive torque sensor device which detects a torque applied to a rotary shaft is provided. The magnetostrictive torque sensor device includes a magnetostrictive portion provided on a surface of the rotary shaft, a coil and a cylindrical back-yoke disposed in outer periphery of the coil. The coil includes a bobbin arranged in outer periphery of the magnetostrictive portion, and a wire wound around the bobbin. A slit is provided on the back-yoke.