DIFFERENTIAL TORQUE MEASUREMENT DEVICE

摘要

A device for measuring the torque exerted on a shaft, comprising an essentially cylindrical magnetic circuit arranged around the shaft and including a permanent magnet and, at the rotor, a variable air gap having two mutually facing portions secured to the shaft in respective longitudinally offset positions along the shaft such that a shaft torque causes a change in the air gap depending on the torque direction, and an assembly for measuring the resulting change in the air gap. Said device comprises two magnetic circuits (C1, C2) each provided with at least one magnetic flux-generating permanent magnet (10, 11) and at least one variable air gap, said circuits being arranged in longitudinally offset positions along the shaft (1). The magnetic circuits (C1, C2) comprise a common central yoke portion (13) combined with at least one measuring portion (15) responsive to the algebraic sum of the magnetic fluxes.