Abstract: A torque absorber adapted for power transmission systems, in which raceway surfaces of the inner and outer rings are of mono-hyperboloid of revolution, rollers are arranged between the raceways so as to come into line contact with the raceways at an angle slanting to a plane including the center axis of the inner ring, a power transmission rotation body or the housing is connected to the inner and outer rings through a bearing or pins, and a spring plate is provided therein to push the outer ring.