A planetary gear drive system in which the planetary gears are made of a resilient plastic or polymer compound so as to allow slippage within the system in response to over-torqueing, and a reverse drive incorporating the planetary gear drive system for use on motor vehicles.

A planetary gear train of an automatic transmission for a vehicle may include an input shaft for receiving an engine torque, an output shaft for outputting a shifted torque, a first planetary gear set, a second planetary gear set, a third planetary gear set, a fourth planetary gear set, a first shaft, a second shaft, a third shaft, a fourth shaft directly connected to the input shaft, a fifth shaft, a sixth shaft selectively connectable to the second shaft, a seventh shaft selectively connectable to the second shaft and the fifth shaft respectively, and an eighth shaft selectively connectable to the fifth shaft and directly connected to the output shaft.

A transmission system includes planetary gearing with a ring gear, a plurality of planet gears, a carrier, and a sun gear, a forward clutch operatively connected between the ring gear and carrier, a reverse brake operatively connected between the carrier and a rotationally fixed location, and a control subsystem to switch the transmission system between forward and reverse operational modes in the which the ring gear and the sun gear rotate in the same or opposite rotational directions, respectively. A control subsystem actuation stroke can actuate both the forward clutch and the reverse brake based on a common control signal.

A partial reverse clutch assembly comprises a frame, a coupling member, a corrugated swing body, and a cam body. The frame mounts an input gear and an output gear, and, a coupling member that is disposed between input and output gears couple the input gear to the output gear to transmit a motorized rotational drive in a first direction. The swing body is coupled between the input gear and the coupling member and comprises a projecting swing arm. The cam body abuts and defines a sliding contact between the swing body and the coupling member, where a reversal of the motorized rotational drive oppositely rotates the output gear in engagement with the swing arm in a second direction. The cam body is displaced upon contact to with the swing body during the rotation in the second direction to decouple the coupling member between the input gear and the output gear.

A power transmission device includes: a cylindrical member including an opening formed at a first end in an axial direction, and a wall portion formed at a second end in the axial direction; and a planetary gear set received within the cylindrical member; a carrier of the planetary gear set which includes a protruding portion protruding toward an outer circumference side, and the protruding portion being positioned between the wall portion and a ring gear of the planetary gear set, wherein the carrier is integrally formed with a hub portion of a clutch; the hub portion is positioned on a wall portion side of the carrier; and an outermost circumference portion of the protruding portion is positioned radially outside of an outermost circumference portion of the hub portion.

A parking lock for a transmission of an electric or hybrid vehicle is disclosed. The parking lock includes a lock device including an actuatable actuating element and a setting element adjustable between a deployed position and a retracted position. The locking device is configured such that, in response to repeated actuation of the actuating element, the setting element is, via a coupling mechanism, adjusted alternately between the retracted position and the deployed position. A camshaft is provided with a cam arranged on the camshaft that is connected in terms of drive to the lock device. A ratchet wheel is provided with a pawl that is adjustable between an engagement position, where the pawl blocks a rotation of the ratchet wheel, and a release position, where the blocking of the ratchet wheel is released. The setting element adjusts the pawl between the engagement position and the release position.

A power transmission device includes: a cylindrical member including an opening formed at a first end in an axial direction, and a wall portion formed at a second end in the axial direction; and a planetary gear set received within the cylindrical member; a carrier of the planetary gear set which includes a protruding portion protruding toward an outer circumference side, and the protruding portion being positioned between the wall portion and a ring gear of the planetary gear set, wherein the carrier is integrally formed with a hub portion of a clutch; the hub portion is positioned on a wall portion side of the carrier; and an outermost circumference portion of the protruding portion is positioned radially outside of an outermost circumference portion of the hub portion.

A forward/reverse switching mechanism is provided with a planetary gear set, a reverse brake and a forward clutch. The planetary gear set includes a sun gear which serves as an input part, a carrier which serves as an output part, and a ring gear. The reverse brake is adapted to fix the ring gear. The forward clutch is adapted to connect the ring gear and the sun gear to each other. The ring gear, a drive plate provided on a ring gear side of the reverse brake and a driven plate provided on a ring gear side of the forward clutch are spline-fitted to a clutch drum.

A hybrid system for a vehicle including a hybrid machine and a transmission arrangement that includes a first, a second and a third planetary gear set each including a sun gear, a planet carrier and a ring gear, the transmission arrangement further including five shift elements engageable in combinations of two to obtain six forward gear stages, wherein the ring gear of the first planetary gear set and the planet carrier of the second planetary gear set are operatively connected to each other, the ring gear of the second planetary gear set and the planet carrier of the third planetary gear set are operatively connected to each other, two planetary members of the third planetary gear set are selectively connectable to each other by a single one of the shift elements, wherein the hybrid machine and the ring gear of the first planetary gear set are connected to each other.

Disclosed is a forward/reverse switching mechanism (2) with a planetary gear set (3), a reverse brake (5) and a forward clutch (4). The planetary gear set (3) includes a sun gear (31) which serves as an input part, a carrier (34) which serves as an output part, and a ring gear (32). The reverse brake (5) is adapted to fix the ring gear (32). The forward clutch (4) is adapted to connect the ring gear (32) and the sun gear (31) to each other. The ring gear (32), a drive plate (52) provided on a ring gear (32) side of the reverse brake (5) and a driven plate (41) provided on a ring gear (32) side of the forward clutch (4) are spline-fitted to a clutch drum (6).