Abstract: The present invention provides a starting clutch disposed between a transmission and an engine and having a wet type multi-plate clutch for transmitting a power, in which the wet type multi-plate clutch includes a plurality of friction plates housed for an axial sliding movement, a clutch drum for housing the friction plates, and a piston for urging a radial central region or therearound of the friction plate to engage the friction plates, and oil which has lubricated the wet type multi-plate clutch is temporarily trapped within the clutch drum and then is discharged.

Abstract: A wet clutch arrangement, particularly a wet plate clutch or lockup clutch including a first friction face formation coupled with a housing arrangement for rotation around an axis of rotation and a second friction face formation coupled with an output member for rotation around the axis of rotation, and a preferably ring-shaped pressing piston. The pressing piston, together with the housing arrangement, defines a pressure fluid space and is movable in direction of the axis of rotation through a change in fluid pressure in the pressure fluid space for influencing the frictional interaction between the friction face formations. An operant fluid application surface of the pressing piston is in the range of 15000 mm2 to 25000 mm2 for generating a force acting upon the pressing piston.

Abstract: The present invention provides a wet-type multi-plate friction engaging apparatus comprising a clutch portion including internally toothed plates and a piston adapted to apply an urging force for engaging the internally toothed plates and wherein load acting portions acting on the clutch portion are arranged on both sides of the clutch portion, and a contact area of the load acting portion through which the load acting portion is contacted with the clutch portion is located in a predetermined range between about 20% of a radial width of a friction engaging portion from a central position of the friction engaging portion in an outer diameter direction and about 20% of the radial width of the friction engaging portion in an inner diameter direction, and a radial width of the contact area is smaller than about 10% of the radial width of the friction engaging portion.