Patent ID: 6846260

Claim:
An automatic transmission comprising: a torque convener comprising a pump impeller, a turbine runner, and a stator; a transmission input shaft to which the turbine runner is attached; a transmission mechanism that changes a transmission ratio to change input torque and input speed transmitted to the transmission input shaft; a stator shaft that supports the stator on an outer periphery and rotatably supports the transmission input shaft on an inner periphery; a magnetostrictive torque sensor that detects a magnitude of the input torque transmitted to the transmission input shaft; the magnetostrictive torque sensor comprising: (i) a magnetic material having a magnetostrictive property and attached onto an outer periphery of the transmission input shaft; and (ii) a cylindrical magnetic-property detector mourned on the inner periphery of the stator shalt and arranged to be opposite to the magnetic material to detect a change in a magnetic property of the magnetic material, occurring owing to the input torque applied to the transmission input shalt; and a torque-sensor retaining sleeve fitted to the inner periphery of the stator shaft, wherein the torque-sensor retaining sleeve is configured to prevent axial motion of the magnetostrictive torque sensor relative to the stator shaft to retain the magnetostrictive torque sensor at a predetermined installation position.