Abstract: A torque limiter having a locking stud which radially slides in a drive part enters an associated slot in the inner periphery of a driven part coaxial with the drive part under the action of a radial-thrust blade spring. When an excessive torque is present between the drive and driven parts, the stud tends to leave its housing to disengage the drive and driven parts and thereby it laterally and outwardly clears intermediate rollers in order to decrease the distance between the spring and the stud and so that the force applied by the spring shall not increase during such unlocking.Thus the unlocking is immediate and the oscillatory zone of the prior-art limiters is virtually eliminated.