Abstract: A first power train (T1) for driving a pair of front drive wheels (Wf1, Wf2) comprises a transmission (4) connected to an engine (2) and a front drive train (41f) connected to the drive wheels, the front drive train including a final reduction gear (43), and a second power train (T2) for driving a pair of rear drive wheels (Wr1, Wr2) comprises a rear transfer train (11) branched from the first power train, between the transmission and the front drive train, and a rear drive train (41r) connected to the rear drive wheels.

Abstract: Drive torque input to a rotatable differential case (3) is differentially distributed, through a pinion gear (25) rotatably supported by the different al case, to a pair of torque outputting side gears (27, 29) accommodated in the differential case and meshing at their toothed portions (27b, 29b) with the pinion gear, and a pair of difference limiting clutches (35, 37) for frictionally slippingly coupling the differential case with the pair of side gears each comprise a frictional region (7b, 5b) of a cone frustum figure on an inner wall (7a, 5a) of the differential case, a frictional region (27d, 29d) of a cone frustum figure on an outer wall (27c, 29c) of a body portion (27a, 29a) of either side gear, and a taper ring (47) rotatably interposed between the frictional regions which have different average friction radii (r1, r2) generating different average frictional forces.

Abstract: A differential apparatus has a differential casing, a pinion gear, a pair of side gears engaged with the pinion gear, and a cone clutch for limiting a differential movement between the side gears. In this differential apparatus, the cone clutch is constructed by a female side cone portion formed in an inner circumference of the differential casing, and a male side cone portion formed in an outer circumference of the pair of side gears. The female side cone portion is formed in the shape of a tapered face in which a conical generating line is a straight line. The male side cone portion is formed in the shape of a tapered face having a predetermined curvature and a generating line projecting to the female side cone portion. Thus, no sliding portion is offset to a small diameter portion even when thrust applied to the cone clutch is increased, thereby improving durability of the cone clutch.

Abstract: A differential apparatus includes a differential casing, a pair of helical side gears and a pair of helical pinion gears. The helical pinion gears are accommodated in bores formed in the differential casing, respectively. The long and short helical pinion gears have respective first gear portions meshing with the side gears, respectively, and second gear portions meshing with each other. Each gear tooth of the long pinion gear is so tapered that tip thickness of the gear tooth is gradually decreased from an axial end of the gear portion toward the other gear portion. Even if the long pinion gear is inclined by meshing reactive forces, it is possible to ensure sufficient tooth bearing areas at respective tooth faces of the pinion gears.

Abstract: A differential apparatus includes a differential casing, a pair of helical side gears and a pairs of helical pinion gears. The helical pinion gears are accommodated in bores formed in the differential casing, respectively. When it is expected that a helix angle of tooth trace of the helical pinion gear would be decreased by the vehicle's driving, one of the helical pinion gears is formed in advance so that the tooth depths are gradually decreased from axial ends of the helical pinion gear toward the axial intermediate potion. Conversely, when it is expected that a helix angle of tooth trace of the pinion gear would be increased by the vehicle's driving, one of the helical pinion gears is formed in advance so that the tooth depths are gradually increased from the axial ends of the helical pinion gear toward the axial intermediate potion.