A hydraulic control system for a transmission is provided with a power source, two drive wheels, a power transmission device, a hydraulic pump, a main valve, and a controller. The power transmission device is configured to be set to a plurality of speed stages. The main valve is disposed between the hydraulic pump and the power transmission device and adjusts the main pressure of hydraulic fluid supplied from the hydraulic pump to the power transmission device. The controller controls the main valve. The controller sets the main pressure to a pressure value derived by correcting a clutch holding pressure of the set speed stage based on a load applied to each of the drive wheels.

A transmission for an agricultural or heavy load vehicle is provided, and includes a central drive shaft, at least one planetary gearset comprising a planet carrier, at least one output drive element, and one brake device. The drive shaft is connected to the output drive element via the planetary gearset. The brake device is located between the planet carrier and the output drive element in the form of a ring gear, such that the output drive element can be coupled to the planet carrier via the brake device.

A transmission structure of the present invention causes, during a period from a time point when a rotational speed of a drive rotational power reaches a predetermined first/second speed stage shift-up start speed until a first/second speed stage shift-up end time point, one of an input-side clutch mechanism pair and an output-side clutch mechanism pair to be in a double transmitting state, and causes, in the double transmitting state, a first clutch mechanism and a second clutch mechanism of the other one of the input-side clutch mechanism pair and the output-side clutch mechanism pair to be shifted to a disengagement sate and an engagement state, respectively, while having frictional plate slid.

An electric drive axle of a vehicle includes an electric motor having an output shaft. An idler assembly is drivingly coupled to the electric motor and a differential. The idler assembly includes a first gear-clutch assembly to facilitate a first gear ratio and a second gear-clutch assembly to facilitate a second gear ratio.

A transmission assembly includes a common ring gear assembly, a first sun gear, a first planet carrier, a second sun gear and a second planet carrier. A set of planet gears of each one of the first and second planet carriers meshing with the common ring gear assembly. The set of planet gears of the first planet carrier meshing with the first sun gear and the set of planet gears of the second planet carrier meshing with the second sun gear. The transmission assembly further includes a transmission housing.

The second sun gear is adapted to be connected to a transmission input shaft;

the common ring gear assembly is adapted to be connected to a transmission output shaft, and

the second planet carrier and the first sun gear are operatively connected to each other.

Methods and systems for an electric drive axle of a vehicle are provided. An electric drive axle system includes, in one example a gear train configured to rotationally attach to an electric motor-generator, the gear train includes an output shaft having a clutch arranged thereon and configured to selectively rotationally couple a gear to the output shaft. The gear train further includes a lubrication channel extending between an output shaft and an axle shaft and including an outlet extending through the output shaft and opening into the clutch.

A work vehicle transmission includes a first transmission mechanism that changes input motive power to any one of multiple speeds, and a second transmission mechanism that changes the motive power changed by the first transmission mechanism to any one of multiple speeds, the number of speeds of the second transmission mechanism being smaller than that of the first transmission mechanism. Multiple speed change multi-disc clutches of the first transmission mechanism are arranged parallel with multiple deceleration multi-disc clutches of the second transmission mechanism so as to be adjacent in the diameter direction thereof.

A power transmission apparatus of a hybrid electric vehicle includes an input shaft configured of receiving an engine torque, a motor shaft configured of receiving a torque of a motor/generator, first and second planetary gear sets respectively having first to third rotation elements and fourth to sixth rotation elements, a first shaft connected to the first rotation element and selectively connectable to each of the input shaft and the motor shaft, a second shaft fixedly connecting the second and fifth rotation elements, and selectively connectable to the input shaft, the motor shaft, and a transmission housing, respectively, a third shaft fixedly connecting the third and fourth rotation elements and selectively connectable to the transmission housing, a fourth shaft fixedly connecting the sixth rotation element and an output gear, and a plurality of engagement elements including at least one clutch and at least one brake.

The automatic transmission has, on an axis of a power transmission shaft: a one-side clutch including a plurality of friction plates; and an other-side clutch including a plurality of friction plate. A pressing section of a piston of the one-side clutch and a pressing section of a piston of the other-side clutch are arranged to overlap each other in an axial direction. On one side in the axial direction of the plurality of friction plates of the one-side clutch, a radial section of the piston of the one-side clutch and a radial section of the piston of the other-side clutch are arranged in parallel in the axial direction. Pressure-receiving sections of the pistons of the one-side clutch and the other-side clutch and bearing sections of the pistons of the one-side clutch and the other-side clutch are aggregated and arranged on a radially inner side.

A power transmission device includes a first shaft provided to be rotatable around a first rotational axis of the hydraulic pump driven by the engine. A second shaft is rotatable about the first rotational axis to rotate the power take shaft. A clutch is rotatable about a second rotational axis that is substantially parallel to the first rotational axis and is vertically below the first rotational axis. The clutch has a first rotating portion and a second rotating portion arranged to face each other in the second rotational axis. A first rotating portion is connectable to and separable from the second rotating portion. The first rotation transmission mechanism is configured to transmit rotation of the first shaft to the first rotating portion. A second rotation transmission mechanism is configured to transmit rotation of the second rotating portion to the second shaft.