An automatic transmission includes a clutch device having a clutch hub, a clutch drum, a friction plate, a piston, and a hydraulic chamber. The clutch drum includes an outer-side cylindrical portion, a disc-shaped first radial portion extending radially inwardly, an axial portion extending axially from the first radial portion, and a disc-shaped second radial portion extending radially inwardly from the axial portion. The piston includes a pressing portion disposed between the first radial portion and the friction plate side, and a disc-shaped piston radial portion extending radially inwardly from the pressing portion. The hydraulic chamber is provided radially inwardly from the axial portion and on the non-friction-plate side of the piston radial portion. A comb-teeth portion is provided at a radially intermediate portion of the piston radial portion. The axial portion and the piston radial portion intersect with each other in a comb-teeth shape.

A hybrid drive system for a motor vehicle includes an input shaft, which introduces torques from an internal combustion engine into the hybrid drive system and which is mounted rotatably around an axis of rotation. An output shaft is arranged coaxially to the input shaft. The system also includes an electric machine having a stator and a rotor, and a hub non-rotatably connected to the rotor. The system further includes a wet clutch which has a first actuating piston. The hub is formed as a one-piece forged part and has a first running surface for the first actuating piston. The wet clutch is provided to non-rotatably connect the hub to the output shaft.

A transmission including an electric machine, a torque converter and a planetary gearset in a transmission housing that is connected to an engine. A turbine shaft is configured to transfer torque from the engine and the electric machine to the planetary gear set. A disconnect clutch selectively couples the input shaft from the engine to the torque converter housing of the torque converter. The disconnect clutch includes a disconnect clutch piston and a first balance dam. A torque converter clutch selectively connects the torque converter housing to the turbine and the turbine shaft. The torque converter clutch includes a torque converter clutch piston and a second balance dam. Ports in the housing permit automatic transmission fluid to flow between the turbine shaft and the torque converter clutch piston; the turbine shaft and the torque converter clutch piston; and the turbine shaft, the first balance dam, and the second balance dam.

A propulsion system for an electric vehicle including an internal combustion engine and an electric machine disposed in a transmission housing that is attached to the engine. An engine vibration damper is disposed between the engine and the electric machine. A torque converter connects the engine to the turbine shaft and is disposed in the housing radially inboard of the windings of the electric machine. A turbine shaft connected to the electric machine is configured to transfer torque from the engine and the electric machine through the turbine shaft to a planetary gear set connected to the turbine shaft. A disconnect clutch is operatively connected between the engine and the electric machine and is disposed in the housing radially inboard the windings of the electric machine and is connected to the turbine shaft.

An intermediate wall is provided with a return oil hole through which oil discharged from a friction engagement device returns toward an oil reservoir. A chain drive is disposed adjacent to the intermediate wall. The chain drive transmits a driving force from an input member and/or a rotary electric machine to an oil pump. There is provided an oil guide through which oil flowing through the return oil hole is guided to a region other than a chain placement region inside a case. The chain placement region is a region where a chain of the chain drive is placed.

Systems and methods for an interaxle differential (IAD). In one example, the IAD comprises a locking assembly that includes a friction clutch, the friction clutch includes a clutch pack that comprises plurality of plates configured to engage and disengage to inhibit and permit speed differentiation between a first axle differential and a second axle differential. The IAD further includes a supply lubrication passage that comprises an inlet that receives a lubricant from an enclosure surrounding an input gear of an axle differential and a first outlet flowing the lubricant to a gear coupled to the clutch pack.

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.

Methods and systems for a vehicle transmission are provided. A transmission system includes, in one example, an intermediate shaft rotationally coupled to an input shaft and an output shaft, wherein the input shaft is configured to receive rotational input from an electric machine. The system further includes a first gear coupled to the intermediate shaft, and a plurality of clutches coupled to the input shaft and the output shaft and configured to in a first mode, transfer power directly between a second gear coupled to the input shaft, the first gear, and a third gear coupled to the output shaft, and in a second mode, transfer power indirectly between the second gear, the first gear, and/or the third gear.

An automatic transmission includes: a frictional engagement element including first and second annular friction plates; a pressing member moving in the axial direction relative to the transmission case and press the frictional engagement element in the axial direction; and a lubricating oil. Further, the transmission case includes a contact portion on the inner wall so that the contact portion is separated from a back surface of the pressing member when the frictional engagement element is in an engagement state and comes into contact with the back surface of the pressing member when the frictional engagement element is in a disengagement state.

One aspect of the disclosure relates to a sliding member. The sliding member includes: a first sliding portion having a first lubricant placed between first parts of a first friction sliding mechanism; a second sliding portion having a second lubricant placed between second parts of a second friction sliding mechanism; and a third sliding portion having a third lubricant placed between third parts of a third friction sliding mechanism. The first sliding portion is in contact with the third lubricant, and the second sliding portion is not in contact with the third lubricant. The second lubricant contains an additive containing conductive carbon, and the third lubricant contains no conductive carbon. The second lubricant contains a relatively larger amount of the conductive carbon than the first lubricant.