Abstract: A lock-up device includes a clutch part and a damper mechanism. The damper mechanism includes an input plate, an output plate, a plurality of torsion springs, an intermediate member and a restriction member. The intermediate member is configured to cause at least two of the torsion springs to act in series. The restriction member is fixed to a clutch output member of the clutch part, while being disposed such that a part of the intermediate member is interposed between the input plate and the restriction member in an axial direction. The intermediate member is restricted from moving in a radial direction by the clutch output member, while being restricted from moving in the axial direction by the input plate and the restriction member.

Abstract: A lock-up device includes a clutch part and a damper mechanism. The clutch part includes a clutch input member, a clutch output member, a drive plate, a driven plate, a second flange and a piston. The second flange is mounted between a front cover and an inner peripheral part of a turbine to be axially immovable with respect to the front cover, and forms a lock-up oil chamber. The piston is mounted between the front cover and the second flange, forms a lock-up oil chamber together with the second flange therebetween, and is configured to be moved toward the front cover by an operating oil to be supplied to the lock-up oil chamber.