A first ring gear of a drive unit is connected to a second carrier and is mechanically connected to a counter shaft. A first sun gear is connected to a second sun gear and a first rotary electric machine. A first clutch selectively switches between a connection state and a disconnection state of the first sun gear and an engine. A second clutch selectively switches between a connection state and a disconnection state of a first carrier and the engine. A brake selectively switches between a fixed state and a release state of a second ring gear to and from a fixing member.

A hybrid powertrain and a method for controlling the powertrain are provided to convert an EV mode, a power slit mode, and a parallel mode based on a driving state. The powertrain includes an input shaft connected to an engine and first and second motors/generators installed within a transmission housing. A planetary gear set is installed on an input shaft and includes a combination of a sun gear, a planetary carrier, and a ring gear. A first output gear is connected to the second motor/generator and a second output gear is connected to the planetary carrier of the planetary gear set. A rotation restraint mechanism restricts a rotation of the input shaft. An overdrive brake is connected to the sun gear of the planetary gear set or the first motor/generator. An output shaft is supplied with power through the first and second output gears.

A hydraulic pressure control device of a vehicle driving device, the hydraulic pressure control device includes a range switcher having a first signal solenoid valve capable of supplying a first signal pressure and a spool switchable between a first position reached via the first signal pressure and a second position reached via a biasing force of a biasing member.

A control device for a vehicle is provided. The control device includes an electronic control unit that is configured to: exert the torque of an input member on a fixed member and a rotating member such that the fixed member and the rotating member are separated from each other, when the thrust is exerted for making the engagement teeth mesh with each other; estimate an inclination angle of tooth surfaces based on a relative movement amount between the fixed member and the rotating member, and a relative rotational amount between the fixed member and the rotating member; estimate a frictional coefficient of the tooth surfaces based on the inclination angle; and control the thrust of the actuator according to the frictional coefficient.

A control system for a hybrid vehicle that shift an operating mode to an appropriate mode from a low mode or high mode. The hybrid vehicle comprises a power split mechanism connected to an engine and a first motor. When a required brake torque of a prime mover cannot be achieved during propulsion in an operating mode established by engaging one of clutches while stopping the engine, the control system excites a motoring of the engine by the first motor while maintaining engagement of the clutch engaged to establish the current operating mode.

A power transmission device comprises an engine arranged on a shaft and a first motor. A second motor is arranged on a different shaft from the shaft on which the engine is arranged. A first differential mechanism has a sun gear to which the first motor is connected, a carrier to which the engine is connected, and a ring gear to which the second motor and a drive wheel are connected. A second differential mechanism has a first rotational element to which the first motor is connected, a second rotational element, and a third rotational element to which the engine is connected, and is arranged such that the first motor is located between the first differential mechanism and the second differential mechanism. A case houses the second differential mechanism. A brake mechanism is configured to restrict rotation of the second rotational element and is arranged in the case.

A transmission system of a hybrid electric vehicle may include an input shaft connected to an engine, a planetary gear set including a first rotation element operated as an output element, a second rotation element connected to the input shaft and operated as an input element, and a third rotation element operated as another output element, a first motor operably connected to the first rotation element, and selectively connected to a transmission housing, a first motor/generator configured to generate electric energy by receiving torque through the first motor shaft, a second motor shaft being a hollow shaft, disposed at a radial exterior of the first motor shaft without rotational interference with the first motor shaft, and operably connected to the third rotation element so as to receive torque of the engine, and a second motor/generator disposed on the second motor shaft and outputting torque through the second motor shaft.

A vehicle including a housing supported on a framework member of the vehicle via a supporting member, a liquid medium supply unit fixed to the housing and driven by a motor to supply a liquid medium to a cooled or lubricated portion, and a first atmosphere communicating mechanism that establishes a communication between an inside of a motor portion of the liquid medium supply unit and atmosphere, the first atmosphere communicating mechanism including a volumetric member that is disposed apart from the liquid medium supply unit in a position higher than the liquid medium supply unit, that has a predetermined volumetric space, and that is fixed to the housing.

A control apparatus for a vehicle provided, with a step-variable transmission, includes: a feedback control portion; an input torque resetting control portion; a target input torque setting portion operated upon an increase of the accelerator pedal operation amount in the process of the shift-down action in a power-off state of the vehicle, to restrict an amount of increase of the input torque target value with respect to an amount of increase of an operator-required input torque value, so as to keep the target value not larger than an upper limit value until termination of the input torque resetting control; and an actual input torque increasing portion operated upon the increase of the accelerator pedal operation amount prior to initiation of the inertia phase, to implement an input torque increasing control to control the input torque so as to be larger than the target value, prior to the inertia phase initiation.

Methods and systems for a vehicle transmission are provided. In one example, a vehicle transmission system is provided that includes a first planetary gear set rotationally coupled to a second planetary gear set, a first electrical machine rotationally coupled to a sun gear in the first planetary gear set, and a second electrical machine rotationally coupled to a sun gear in the second planetary gear set. The transmission system also includes an inter-axle differential including a third planetary gear set rotationally coupled to a first axle and a second axle and selectively rotationally coupled to the first planetary gear set and the second planetary gear set, wherein the inter-axle differential is configured to selectively enable and disable speed differentiation between the first and the second axles.