A power transmission device outputting torque from a first power source and a second power source to axles, is provided with: a first shaft coupled with the first power source; a differential configured to differentially distribute the torque to the axles; a first gear set configured to drivingly couple the first shaft with the differential; a second shaft coupled with the second power source; a second gear set drivingly coupled with the second shaft; a clutch configured to receive fluid pressure to drivingly and releasably couple the second gear set with the first gear set; and a pump driven by a third power source at least independent of the first power source and the clutch to generate the fluid pressure, the pump being disposed separate from the clutch and in fluid connection with the clutch to supply the fluid pressure.

A differential device is provided with: a ring gear having a tooth row arranged around an axis to mesh with an input gear; an outer case combined with the ring gear and rotatable about the axis; an inner case rotatable about the axis relative to the outer case and having a toothed end with axially projecting dog teeth; a differential gear set supported by the inner case and to be coupled with a pair of axles to allow differential motion between the axles; a clutch member engaging with the outer case and disconnectably connecting with the dog teeth so as to prevent the inner case from rotating relative to the outer case; and perforations penetrating the outer case and opened on an outer face of the outer case, the perforations being so disposed as to expose the dog teeth radially outwardly from the outer case.

A transmission device includes a power-transmission case having a carrier of a reduction gear and a differential case joined to the carrier is supported in a transmission case via case support bearings, a specific planetary gear portion of a planetary gear is disposed on one side of a differential mechanism in an axial direction, and the specific case support bearing is disposed on the other side thereof An oil passage-forming body is provided on an inner wall of the transmission case, the oil passage-forming body comprising an oil collection part that opens upward and can collect lubricating oil splashed up in an area around the specific planetary gear portion within the transmission case accompanying rotation of the power-transmission case, and an oil reservoir part that is continuous from the oil collection part, stores lubricating oil collected by the oil collection part, and supplies the lubricating oil to the specific case support bearing.

Provided is a structure for lubricating a clutch, the structure including: an oil capturing groove provided along an inner circumference of a ring gear at one side of a pinion gear; and an oil hole connected to an inside of a clutch hub through the oil capturing groove.

Systems for an electric drive axle of a vehicle are provided. In one example, an electric drive axle system includes a gear box including a plurality of gear ratios. The plurality of gear ratios includes a fixed center distance measured from a carrier to an axle on which a plurality of gears or a plurality of pinions is arranged. Each pinion of the plurality of pinions is differently sized, wherein all pinions except for a largest pinion include a pinion baffle. Each gear of the plurality of gears is differently sized, wherein all gears except for a largest gear include a gear baffle.

A vehicle powertrain may include a differential assembly having a housing disposed partially in a lubrication reservoir. The differential assembly translates rotational motion of a pinion gear to a pair of axle shafts extending from the housing and permits different rotational speeds of the axle shafts. One or more components of the differential assembly, e.g., one or more side gears, may include a plurality of radial grooves configured to distribute a lubricant from the lubrication reservoir while the first side gear rotates.

This strain wave gear unit includes: a bottomed cylindrical first internal gear having internal teeth formed on a cylindrical part and a teeth-non-formed part protruding farther inward than the tooth bottom of the internal teeth in a corner area where a bottom wall part is integrally connected to the cylindrical part; a flexible cylindrical external gear having external teeth meshing with the internal teeth of the first internal gear, an opposed part opposed to the teeth-non-formed part with a gap therebetween, and an end part opposed to the bottom wall part to make contact therewith; a second internal gear arranged adjacent to the first internal gear and having internal teeth meshing with the external teeth; and a rotation member that causes the external gear to deform in an oval shape and causes the meshing position to move while partially meshing with the first internal gear and the second internal gear.

An gear case assembly for a watercraft propulsion system has a gear case housing, a driveshaft with a partially threaded bore defined in an end thereof, and a propeller shaft. The propeller shaft and the driveshaft are angled relative to each other. A bevel gear is mounted to the propeller shaft. A pinion mounted to the end of the driveshaft. The pinion meshes with the bevel gear. The pinion defines a central aperture. A fastener is disposed at least in part in the central aperture of the pinion. The fastener fastens the pinion to the end of the driveshaft. The fastener has a head and a shank. The shank is at least partially threaded. The shank extends into the bore of the driveshaft. An outboard motor having the gear case assembly is also disclosed.

In a differential device including a pair of side gears, a plurality of pinion gears and a pinion shaft, the pinion shaft includes a plurality of shaft parts rotatably fitted to and supporting the plurality of pinion gears respectively, and an annular support part linking the plurality of shaft parts to each other, an annular recess portion is formed in an inner peripheral face of the support part, the pinion shaft has an oil guide part that guides lubricating oil within the recess portion to a part where the shaft part and the pinion gear are fitted together, and an inner end portion of at least one of the side gears protrudes into an inner space of the support part and is positioned within a width of the recess portion in an axial direction of the rotating shaft.

Arrangement (1) comprising an electric machine (2), a gearbox (3), a shaft (9) coupling the electric machine (2) with the gearbox (3) and having an axial blind bore (18) extending from a machine-side end (19) of the shaft (9) into the gearbox (3), a coolant insertion element (21) configured to supply a coolant into the bore (18) and a coolant conduction element (22) extending inside the bore (18) from the machine-side end (19) into the gearbox (3) and defining a flow path (23) for the inserted coolant.