Patent attributes
An inventive torque detection device includes: a magnetic circuit forming member provided at a rotating body to which a torque is applied; a magnetic flux collecting ring for collecting a generated magnetic flux; a detection part for detecting, based on the density of the collected magnetic flux, the torque applied to the rotating body; a holding ring, having a flange, for holding the magnetic flux collecting ring and the detection part; and a sealing ring for sealing between the flange and a housing. The holding ring further has: a concave portion for equalizing the thickness of the holding ring at a region thereof close to the flange; and a prevention wall that is continuous with the flange and brought into contact with an inner circumferential face of the sealing ring so as to prevent the displacement of the sealing ring into the concave portion