An electric drive axle in a vehicle is provided. The electric drive axle includes, in one example, an electric motor-generator, a gearbox, and a differential. The gearbox comprises a planetary gear set that includes a sun gear configured to rotate on a sun gear shaft directly coupled to a rotor of the electric motor-generator and an intermediate shaft that includes an idler gear rotationally coupled to a pinion gear that is rotationally coupled to the carrier.

An axle includes: a driven disc, an inner peripheral surface of the driven disc being a first contact surface; a half shaft connector in transmission with the driven disc, the half shaft connector including a second contact surface on its outer periphery, one of the first contact surface and the second contact surface being a circular ring surface, and the other thereof being a polygonal surface; and a differential lock device including rolling members, a rolling holder, a switching driving member, a switching driven member and a second elastic reset mechanism, a plurality of rolling members being arranged in one-to-one correspondence with a plurality of faces of the polygonal surface, and the switching driving member selectively driving the switching driven member to move, to make the rolling members move to an engaged position.

An axle includes: a driven disc, an inner peripheral surface of the driven disc being a first contact surface; a half shaft connector in transmission with the driven disc, the half shaft connector including a second contact surface on its outer periphery, one of the first contact surface and the second contact surface being a circular ring surface, and the other thereof being a polygonal surface; and a differential lock device including rolling members, a rolling holder, a switching driving member, a switching driven member and a second elastic reset mechanism, a plurality of rolling members being arranged in one-to-one correspondence with a plurality of faces of the polygonal surface, and the switching driving member selectively driving the switching driven member to move, to make the rolling members move to an engaged position.

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.

A drive transmission device according to one embodiment of the disclosure includes a single differential unit to which rotation of a motor is transmitted and two speed reducers each having an operation output shaft that is coupled to the differential unit and a carrier that changes a speed of the rotation of the operation output shaft and outputs the rotation. The two speed reducers are arranged such that they are opposed to each other along a second rotation axis, and the operation output shaft and the carrier in each speed reducer are aligned in the second rotation axis direction.

A drive transmission device includes a first member and a second member rotatably coupled about a rotation axis; a drive source generating a rotational force that drives the first member and the second member; speed reducers transmitting the rotational force from the drive source to the second member; at least two bracket portions arranged in the rotation axis direction in the second member; and a flange portion extending in a direction intersecting the rotation axis, having an overlapping region where the flange portion overlaps the bracket portion viewed from a direction along the rotation axis direction, and connecting the speed reducer and the bracket portion. A restricting member that extends in the rotation axis direction and restricts the relative rotational movement between the bracket portion and the flange portion, and a receiving portion that receives the restricting member are provided in the overlapping region.

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 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 differential system includes a differential and a differential disconnect mechanism. The differential includes an outer differential housing and an inner differential housing. The differential disconnect mechanism includes a disconnect clutch, first end face teeth and second end face teeth. The first end face teeth are disposed between the outer differential housing and the inner differential housing and are movably connected with the outer differential housing so that the first end face teeth can move axially and rotate synchronously relative to the outer differential housing. The second end face teeth are fixedly connected with the inner differential housing. The disconnect clutch is connected with the first end face teeth, and is configured to drive the first end face teeth to move axially relative to the second end face teeth.

A differential system includes a differential and a differential disconnect mechanism. The differential includes an outer differential housing and an inner differential housing. The differential disconnect mechanism includes a disconnect clutch, first end face teeth and second end face teeth. The first end face teeth are disposed between the outer differential housing and the inner differential housing and are movably connected with the outer differential housing so that the first end face teeth can move axially and rotate synchronously relative to the outer differential housing. The second end face teeth are fixedly connected with the inner differential housing. The disconnect clutch is connected with the first end face teeth, and is configured to drive the first end face teeth to move axially relative to the second end face teeth.