Torque sensor used for robot arm, has an exertion support body exerting the torque to an annular deformation body

A torque sensor which detects torque around a predetermined rotation axis, the torque sensor comprising:

• an annular deformation body disposed so as to surround a circumference of the rotation axis, the annular deformation body undergoing elastic deformation by exertion of torque;
• an exertion support body provided on one side in a direction along the rotation axis, the exertion support body exerting the torque to the annular deformation body;
• a fixing support body provided on an other side in a direction along the rotation axis, the fixing support body fixing the annular deformation body;
• and
• a detection circuit which outputs electric signals indicating torque around the rotation axis;
• wherein
• the annular deformation body has four coupling parts, and four detection parts positioned between two coupling parts which are adjacent in the circumferential direction of the annular deformation body, the four detection parts undergoing elastic deformation by exertion of torque,
• the four detection parts each are formed in a convex shape on one side in a direction along the rotation axis and are formed in a concave shape on the other side in a direction along the rotation axis,
• the detection circuit outputs the electric signals on the basis of elastic deformation undergone to the four detection parts of the annular deformation body.