An automatic transmission that includes a speed change mechanism including a gear mechanism that can attain a plurality of shift speeds, and a plurality of friction engagement elements that are selectively engaged to attain each shift speed in the gear mechanism; a hydraulic control device that can regulate engagement pressures to be supplied to hydraulic servos of the plurality of friction engagement elements and that can supply lubricating oil that lubricates the speed change mechanism; and a control unit that sends a command about the engagement pressures to the hydraulic control device to control engagement states of the plurality of friction engagement elements.

Desired is a control device for a vehicle drive apparatus capable of determining an engagement failure in an engagement device when shifting a transmission device to a neutral state and making the rotational speed of a driving force source reduced. In order to shift a transmission device from a state in which an object shift speed is established and the vehicle is traveling to a neutral state in which no shift speed is established in the transmission device (#02), when an object engagement device is disengaged while maintaining engagement of a non-object engagement device and the rotational speed of a driving force source (#04, #06) is made to be reduced, an engagement failure in the object engagement device (#02, #07) is determined based on a change in the rotational speed of an input member.

Methods and systems are provided for a multi-speed transmission. The multi-speed transmission includes a housing, an electric motor with a stator and a rotor positioned within the housing, and a planetary assembly positioned on a first axial side of the electric motor. The transmission further includes a first and second clutch unit spaced away from one another, each including a synchronizer, and designed to selectively rotationally couple to the rotor and to rotationally couple the rotor to different gears in the planetary assembly and where the electric motor and planetary assembly are coaxially arranged.

Methods and systems for a clutch assembly in an electric drive axle of a vehicle are provided. In one example, a clutch assembly in a gear train is provided that includes a locking clutch. The locking clutch includes a gear including a plurality of teeth having at least one tooth with a tapered end, an indexing shaft rotationally connected to an output shaft, a shift collar mounted on the indexing shaft, configured to translate on the indexing shaft into an engaged and disengaged configuration, and including a plurality of teeth on a face, where at least one tooth in the plurality of teeth in the shift collar includes a tapered end, and an indexing mechanism coupled to the shift collar and the indexing shaft and configured to accommodate for indexing between the indexing shaft and the shift collar during shift collar engagement.

Methods and systems for a clutch assembly in an electric drive axle of a vehicle are provided. In one example, a clutch assembly in a gear train is provided that includes a locking clutch. The locking clutch includes a gear including a plurality of teeth having at least one tooth with a tapered end, an indexing shaft rotationally connected to an output shaft, a shift collar mounted on the indexing shaft, configured to translate on the indexing shaft into an engaged and disengaged configuration, and including a plurality of teeth on a face, where at least one tooth in the plurality of teeth in the shift collar includes a tapered end, and an indexing mechanism coupled to the shift collar and the indexing shaft and configured to accommodate for indexing between the indexing shaft and the shift collar during shift collar engagement.

A power system includes an engine; a sensor to determine an engine speed; and a transmission. The transmission includes an input element configured to receive the power from the engine as input torque; an output element configured to provide at least a portion the power from the engine as output torque; and a clutch arrangement to transform the input torque into output torque. The clutch arrangement includes at least one clutch selectively positionable between a fully engaged state, a partially engaged state in which a portion of the input torque is transformed into the output torque, and a fully disengaged state. A controller is coupled to the at least one clutch and configured to generate clutch commands based at least in part on the engine speed to position the at least one clutch into the fully engaged state, the partially engaged state, or the fully disengaged state.

A gear switching control device of an internal derailleur includes a plurality of planet gear speed change systems; a gear switching control unit; a plurality of axial ratchet control rings for controlling action of a plurality of axial ratchets; a plurality of axial ratchets; and the plurality of axial ratchet control rings are serially connected by the same gear switching control unit; characteristic in that: a gear switching control unit comprising: a track sleeve, one end of the track sleeve is installed with force accept portion and another end thereof is installed with a linking rod which IS used to serially connected a plurality of axial ratchet control rings; each of the axial ratchet control rings is formed with a respective connecting holes; each axial ratchet control ring being installed a cam or cam-like device; various cam having different operating moving range.

A gear switching control device of an internal derailleur includes a plurality of planet gear speed change systems; a gear switching control unit; a plurality of axial ratchet control rings for controlling action of a plurality of axial ratchets; a plurality of axial ratchets; and the plurality of axial ratchet control rings are serially connected by the same gear switching control unit; characteristic in that: a gear switching control unit comprising: a track sleeve, one end of the track sleeve is installed with force accept portion and another end thereof is installed with a linking rod which IS used to serially connected a plurality of axial ratchet control rings; each of the axial ratchet control rings is formed with a respective connecting holes; each axial ratchet control ring being installed a cam or cam-like device; various cam having different operating moving range.

A malfunction part sensing device for an automatic transmission for a vehicle which is arranged to attain a plurality of shift stages by selectively engaging a plurality of frictional engagement elements, the malfunction part sensing device includes: a shift stage monitoring section configured to monitor the shift stages before and after the shift of the automatic transmission; a malfunction sensing section configured to sense the malfunction mode from a behavior of the vehicle which is generated in accordance with the malfunction; and a malfunction part limiting section configured to limit the one of the frictional engagement elements in which the malfunction is generated, based on the malfunction mode and a shift manner by a combination of the shift stages before and after the shift.

Methods and systems are provided for a multi-speed transmission. The multi-speed transmission includes a housing, an electric motor with a stator and a rotor positioned within the housing, and a planetary assembly positioned on a first axial side of the electric motor. The transmission further includes a first and second clutch unit spaced away from one another, each including a synchronizer, and designed to selectively rotationally couple to the rotor and to rotationally couple the rotor to different gears in the planetary assembly and where the electric motor and planetary assembly are coaxially arranged.