and the bosses 48 which are passed through the holes 44 provided in the bottom wall of the driven member 40 thus the driven member 40 and the pressure plate 41 are adapted to rotate integrally together and to be freely movable along the axial direction relative to each other the annular driven clutch plates 49 are fitted over the outer circumferential surface of the driven member 40 by means of the meshing of the spline teeth 42 of the driven member 40 and the similar spline teeth provided in the inner circumferential edges of the driven clutch plates 49 so as to alternate the positions with the drive clutch plates 39 along the axial direction the outer most driven clutch plate 49 is elastically supported by a conical disc spring 85 with respect to the flange 45 of the driven member 40 a lifter plate 50 is attached to the free ends of the bosses 48 of the pressure plate 41 passed through the holes 44 of the bottom wall of the driven member 40 by way of stud bolts 51 which are passed through the lifter plate 50 and the nuts 51a which are threaded to the stud bolts 51 so as to securely hold the lifter plate 50 between the nuts 51a and the end surfaces of the bosses 48 a compression coil spring 52 surrounds each of the bosses 48 and is interposed between the bottom wall.