Torque sensor

摘要

The present invention relates to a magnetostrictive sensor for measuring a torque in a shaft (1). The sensor comprises at least one active magnetostrictive region (2) on the shaft (1), a surface pattern in the magnetostrictive region such that it obtains anisotropic properties, a first means (5) arranged to generate a magnetic field varying in time in the magnetostrictive region (2) and a second means (9) arranged to sense variation in the permeability in the magnetostrictive region (2). Said magnetostrictive region (2) comprises a first layer (3) of a magnetostrictive material which is provided on the surface of the shaft (1) and that said surface pattern is formed by a second layer (4) of a non-magnetostrictive material comprising a low resistivity.