US Patent 7900761 Clutch system

To provide a smaller clutch system with fewer component parts, the clutch system includes a first hydraulic clutch, which is provided between a power source and a first driven shaft, and a second hydraulic clutch, which is provided between the power source and a second driven shaft. An input member includes an annular plate portion, an inner cylindrical portion, and an outer cylindrical portion. The input member is provided commonly to a first and a second hydraulic clutches, while the inner and the outer cylindrical portions are made to be the input sides respectively of the first and the second hydraulic clutches. First and a second clutch pistons, which are included respectively in the first and the second hydraulic clutches, are placed on an opening end side of the input member.