Patent ID: 7967123

Claim:
A wet-type multi-plate friction engaging apparatus comprising: a clutch portion including internally toothed plates each having at least one axial surface on which a friction material is provided and externally toothed plates arranged alternately with said internally toothed plates in an axial direction; and a piston adapted to apply an urging force for engaging said internally toothed plates and said externally toothed plates with each other; and wherein load acting portions acting on said clutch portion are arranged on both sides of said clutch portion, and a contact area of each load acting portion through which said load acting portion is contacted with said 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 said friction engaging portion in an outer diameter direction and about 20% of the radial width of said friction engaging portion from the central position in an inner diameter direction, and a radial width of said contact area is smaller than about 10% of the radial width of said friction engaging portion.