A power transmission device includes a pinion gear having a large pinion gear and a small pinion gear, a carrier that supports the pinion gear, a ring gear that engages with the small pinion gear, an oil supply unit positioned above a horizontal line that passes through a revolution center of the pinion gear, and a downstream side wall part facing a gear surface of the large pinion gear. The downstream side wall part is arranged to be adjacent to the oil supply unit further downstream in a revolution direction of the pinion gear than the oil supply unit when viewed from an axial direction.

A differential device is provided with: a casing rotatable about an axis; a differential gear set including a pair of side gears housed in the casing and rotatable about the axis, a pinion shaft penetrating perpendicular to the axis and being secured to the casing; and pinion gears rotatably supported by the pinion shaft and so meshed with the side gears as to enable differential motion between the side gears; friction clutches interposed between the side gears and an inner periphery of the casing to limit the differential motion; a pair of repulsive bodies respectively applying force in directions along the axis to the friction clutches; and a block in contact with and supporting in the directions along the axis both the repulsive bodies, the block so fitting on the pinion shaft as to impose reaction forces from the friction clutches on the pinion shaft.

A power transmission device includes a bearing, a differential mechanism, a case that houses the differential mechanism, a pinion gear supported by the case, a wall part that overlaps the case in an axial direction, a plate that is provided between the wall part and the case in the axial direction, and that supports the case with the bearing being interposed, and a parking pawl that is rotatably fixed to the plate in a position that overlaps the plate in the axial direction.

A power transmission device includes a box, a case disposed in the box, a differential mechanism housed in the case, and a planetary gear mechanism disposed in the box and supported by the case. The planetary gear mechanism includes a sun gear and a pinion gear that engages with the sun gear. The box has a shelf part above a horizontal line that passes through a revolution center of the pinion gear. The shelf part is arranged at a position that does not overlap the sun gear when viewed from radially above.

A gear assembly is provided that simplifies the integration of a differential assembly into the hollow rotor of an electric motor. The gear assembly utilizes a hollow cross member that includes a central portion and a plurality of hollow extension members onto which the gears are mounted. Within each of the hollow extension members is a pin. When the pins are withdrawn, the assembly fits unimpeded within the hollow rotor. When the pins are partially extended out of the corresponding extension members, the ends of the pins fit within apertures in the rotor. A plug fits within a centrally located thru-hole in the central portion of the hollow cross member, thereby locking the pins in the extended position and locking the gear assembly in place.

A vehicle differential apparatus including a pair of side gears arranged side by side along an axial line, a set of pinion gears disposed on a radial outside of the side gears so as to engage with the side gears and engaged with each other, and a housing forming a housing space of the pinion gears to rotate integrally with the pinion gears. Each of the side gears includes an inner and outer side gears, the inner and outer side gears include a first and second splines extended along helical gears formed on an outer and inner circumferential surfaces of the inner and outer side gears, respectively, and engaging with each other, and the helical gear of the first spline is formed so as to be crowned along a tooth trace thereof.

A differential (1) includes pinion gears (2, 3), a drive wheel (4), and at least one cover (5, 13), wherein: the outside of the drive wheel (4) has toothing (7) extending circumferentially around an axis of rotation (6) and the inside of the drive wheel is provided with bearing points (8, 9); the pinion gears (2, 3) are mounted on the bearing points (8, 9) in the drive wheel (4); and the differential (1) is closed on at least one side by the at least one cover (5, 13).

In a differential device, a differential casing is formed of lightweight alloy, and gears are formed of steel. A plurality of screw hole bosses each including a screw hole to which each of a plurality of bolts is fastened to fasten a ring gear, and a first rib integrally coupling the screw hole bosses together are protrudingly provided at the side face of a flange. A plurality of second ribs integrally coupling the screw hole bosses and a first bearing boss together is provided on the external side face of a differential casing. A first thickened portion including a first gear support portion that supports the back surface of a pinion gear is formed on the circumferential wall of a differential casing body. A second thickened portion that includes a second gear support portion which supports the back surface of a side gear is formed on the first bearing boss.

A drive unit assembly including a differential assembly. The differential assembly includes a ring gear including an annular flange portion having an inner face and a differential case having an inner face configured to cooperate with the inner face of the annular flange portion of the ring gear. The differential case is configured to receive a spider therein, wherein the spider includes a main body including center bore formed therein, and wherein the center bore is configured to receive at least one output shaft therethrough.

A differential with a washer for a gear in a differential housing includes an outer edge at a maximum radial distance from an axis, and an inner edge defining an opening, the inner edge defined in part by an innermost portion at a minimum radial distance from the axis and the inner edge having an outward portion spaced radially outwardly from the innermost portion. The washer also includes an axially and radially inclined sidewall extending at least part of the way between the outer edge and the innermost portion.