Abstract: A damper includes: first and second rotating elements rotatable around a rotation center; an elastic element elastically expanding and contracting in response to relative rotation of the first and second rotating elements; and a limiter provided in the first rotating element. The limiter includes a lining plate having a first sliding surface, a first cover plate having a second sliding surface and a first abutting surface, a second cover plate having an outer edge part and an inner edge part, and a biasing member. When a difference in torque between the lining plate and the first cover plate is a predetermined value or more, the first sliding surface slides with the second sliding surface, and the second sliding surface is inclined with respect to the first abutting surface so as to face the second direction as going radially inward in a free state of the first cover plate.

Abstract: A damper includes: first and second rotating elements rotatable around a rotation center; an elastic element elastically expanding and contracting in response to relative rotation of the first and second rotating elements; and a limiter provided in the first rotating element. The limiter includes a lining plate having a first sliding surface, a first cover plate having a second sliding surface and a first abutting surface, a second cover plate having an outer edge part and an inner edge part, and a biasing member. When a difference in torque between the lining plate and the first cover plate is a predetermined value or more, the first sliding surface slides with the second sliding surface, and the second sliding surface is inclined with respect to the first abutting surface so as to face the second direction as going radially inward in a free state of the first cover plate.

Abstract: A torque limiter unit includes a first metal member and a second metal member (pressure plate, cover plate) pressed against the first metal member with a predetermined pressure, and is configured such that the first metal member and the second metal member are slid relative to each other against a frictional force generated between the first metal member and the second metal member. Further, the first metal member includes, as a sliding surface, a first coating layer including a 3d transition metal-containing compound, and the second metal member includes, as a sliding surface, a second coating layer including a 3d transition metal-containing compound.

Abstract: A method of quenching a sheared portion includes a heating process heating a steel product to a temperature equal to or greater than an austenitizing temperature, a shearing process shearing the steel product which is heated in the heating process to form a sheared portion at the steel product while the steel product is maintained at the temperature equal to or greater than the austenitizing temperature, and a cooling process cooling the steel product at which the sheared portion is formed in the shearing process to a temperature equal to or smaller than a martensitic transformation start point.