The present invention relates to a planetary gear device having four or more shafts. The planetary gear device according to the present invention may be expanded by adding another planetary gear device to the planetary gear device in the related art, all shafts of the planetary gear device are exposed to the outside such that a brake may be easily installed, and the shafts may be divided into two groups and separated. The planetary gear device according to the present invention may be used for an apparatus for connecting, braking, and separating an automatic transmission, a plurality of power supplying shafts, and a plurality of power receiving shafts and used to integrate two apparatuses.

The present invention relates to a planetary gear device having four or more shafts. The planetary gear device according to the present invention may be expanded by adding another planetary gear device to the planetary gear device in the related art, all shafts of the planetary gear device are exposed to the outside such that a brake may be easily installed, and the shafts may be divided into two groups and separated. The planetary gear device according to the present invention may be used for an apparatus for connecting, braking, and separating an automatic transmission, a plurality of power supplying shafts, and a plurality of power receiving shafts and used to integrate two apparatuses.

Systems for a differential are provided. The differential includes two sets of pinion gears with an asymmetric split tooth profile. A case of the differential includes a plurality of lubrication ports which open adjacent to untoothed sections of one set of pinion gears and in a drive mode and an outboard axial load is exerted on the corresponding set of pinion gears.

A vehicle differential apparatus including a pair of side gears arranged side by side along an axial line so as to rotate about the axial line, a set of pinion gears disposed on a radial outside of the side gears so that one pinion gear engages with one of side gears, and the other pinion gear engages with the other of the side gears the one pinion gear, and a housing accommodating the side gears and the pinion gears and including a substantially cylindrical circumferential wall and a side wall extended radially inward from an end of the circumferential wall. The housing includes a space formation portion forming a housing space accommodating the pinion gears so as to rotate integrally with the pinion gears, and the side wall is provided with an opening connecting the housing space and a space outside the housing.

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 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 vehicle differential device includes a plurality of pinion gear sets. Each of the pinion gear sets includes a first pinion gear configured to mesh with a first outer helical gear and a plurality of second pinion gears configured to mesh with a second outer helical gear. The first pinion gear integrally includes an axially one end side gear portion configured to mesh with the first outer helical gear and an axially other end side gear portion configured to mesh with the second pinion gears. The second pinion gears are configured to mesh with the second outer helical gear at positions separated from each other in a circumferential direction of the second outer helical gear, and the axially other end side gear portion of the first pinion gear is configured to mesh with the second pinion gears at positions radially outward of the second outer helical gear.

A vehicle differential device comprises: a differential casing rotatably disposed around a rotational axis; and a pair of side gears rotatably supported by the differential casing and supported in a thrust direction via an annular bearing surface formed in the differential casing to mesh with a pair of pinion gears. The differential casing is provided with a first lubricating oil passage formed in a circumferential direction on an outer circumferential side of the bearing surface in the differential casing, and a first guidance projection projected toward the rotational axis in the first lubricating oil passage and guiding a lubricating oil flowing in a circumferential direction in the first lubricating oil passage due to rotation of the differential casing around the rotational axis, toward a first meshing portion between a first side gear of the pair of side gears and the pinion gears.

A vehicle differential device comprises: a differential casing rotatably disposed around a rotational axis; and a pair of side gears rotatably supported by the differential casing and supported in a thrust direction via an annular bearing surface formed in the differential casing to mesh with a pair of pinion gears. The differential casing is provided with a first lubricating oil passage formed in a circumferential direction on an outer circumferential side of the bearing surface in the differential casing, and a first guidance projection projected toward the rotational axis in the first lubricating oil passage and guiding a lubricating oil flowing in a circumferential direction in the first lubricating oil passage due to rotation of the differential casing around the rotational axis, toward a first meshing portion between a first side gear of the pair of side gears and the pinion gears.

A parallel axis gear configuration constructed in accordance to one example of the present disclosure can include a first gear having a first gear tooth that includes a lead crowning across a face width thereof. The lead crowning can include (i) a first lead crown defined from a centerline to a transition point and (ii) a second lead crown defined from the transition point to a first end point. The lead crowning can include a drop-off magnitude that is greater at the second lead crown than the first lead crown.