Patent ID: 11384824

Abstract:
A lock-up device includes a clutch part, a piston, a sleeve, and an oil chamber plate. The clutch part is disposed between a front cover and a turbine. The piston is axially movable, and brings the clutch part into a torque-transmission state. The sleeve is fixed to the inner peripheral part of the front cover. The sleeve has a piston support part and a first butt part. The piston support part supports an inner peripheral surface of the piston to be axially movable. The first butt part is formed on the outer peripheral surface of the piston support part. The oil chamber plate is provided between the piston and the turbine. The oil chamber plate has a second butt part. The second butt part is butt-welded with the first butt part. The oil chamber plate forms an oil chamber. Hydraulic fluid is supplied between the oil chamber and the piston.