Methods and systems for a transmission are provided herein. In one example, a hydraulic system is provided that includes a boost pump, a relief valve in fluidic communication with the boost pump and a reservoir, and a plurality of control valves in fluidic communication with the boost pump, positioned downstream of the relief valve, and in fluidic communication with a plurality of hydraulic devices. The hydraulic system further includes a controller designed to actively adjust a position of the relief valve based on an aggregate hydraulic pressure demand of the plurality of hydraulic devices to alter a boost pressure of a hydraulic fluid supplied to the plurality of control valves.

The invention relates to a pressure oil filter system for a hydraulic transmission, in particular for a motor vehicle transmission, comprising at least one oil pump which can be actuated as required and which has a pressure side and a suction side, a pressure line to a consumer and at least a first oil filter which is arranged at the pressure side of the oil pump in the pressure line, wherein means for damping pressure surges during intermittent operation of the oil pump are provided in the pressure line upstream of the first oil filter in the flow direction of the oil.

A hydraulic fluid pressure amplifier system includes a boost cylinder assembly, an energy storage device in fluid communication with the boost cylinder assembly, and a working cylinder assembly. The boost cylinder assembly is configured to selectively receive a plunger member into a boost cylinder, wherein movement of the plunger member received in the boost cylinder compresses a charge fluid within a blind side volume of the boost cylinder from a first fluid pressure to an amplified fluid pressure greater than the first pressure. The working cylinder assembly is selectively operable responsive to receiving a source hydraulic fluid having a nominal fluid pressure less than the amplified fluid pressure for effecting the movement of the plunger member into the boost cylinder. The energy storage device is operable to selectively receive and store a portion of the charge fluid compressed to the amplified fluid pressure.

A method for holding a vehicle on a gradient. The vehicle has a transmission with an output, a first clutch and a second clutch. The primary sides of the first and second clutches are mechanically operatively connected to one another. The secondary sides of the first and second clutches are mechanically operatively connected to one another and to the output of the transmission. Different transmission ratios can be engaged by way of the first clutch and the second clutch, and the first clutch is in an engaged state. The method includes the additional closure of the second clutch in order to block the transmission and thus hold the vehicle at a standstill on a gradient.

A method for setting a gear in a transmission of a power tool, the power tool including an electric motor as well as a controller for setting the rotational speed of the electric motor. A transmission includes an operating device for selecting a gear in the transmission, a shift fork as well as an actuator, the operating device including a signal transmitter as well as a sensor for receiving a signal of the signal transmitter. The method includes: setting the operating device from a first position to a second position for selecting a gear in the transmission; detecting a signal by the at least one sensor according to the second position of the operating device; transmitting a signal to the controller; setting the rotational speed of the electric motor from a first value to a second value by the controller; positioning the operating device from the second position into a third position; detecting a signal by the sensor according to the third position of the operating device; transmitting a signal to the actuator; and setting the shift fork from a first position to a second position with the aid of the actuator for the purpose of changing from a first gear into a second gear.

A motor vehicle transmission including an input shaft (AN), an output shaft (AB), a power take-off (1) and a hydraulic pump (2). The hydraulic pump (2) serves to supply the motor vehicle transmission with hydrodynamic working pressure. The power take-off (1) has a power take-off gearwheel (1A). The power take-off gearwheel (1A) is connected to the hydraulic pump (2) in order drive the hydraulic pump (2).

Methods and systems for estimating an amount of torque that is transferred via a differential ring gear assembly are described. In one example, axial displacement of the differential ring gear assembly is determined and converted into a torque estimate. The torque estimate may be used to verify other powertrain torque estimates or for closed loop torque control.

A drive train, including: a first electric motor; a second electric motor; and a transmission system including a first input shaft driveably connected to the first electric motor, a second input shaft driveably connected to the second electric motor, a first gear train including a first gear element rotatably mounted on the first input shaft and a second gear element rotatably mounted on the second input shaft, a second gear train including a third gear element rotatably mounted on the first input shaft and a fourth gear element rotatably mounted on the second input shaft, a gear selector assembly arranged to selectively lock either the first and third gear elements for rotation with the first input shaft or the second and fourth gear elements for rotation with the second input shaft.

A hydraulic arrangement for a vehicle transmission includes a hydraulic pump for providing a system pressure for a first hydraulic system circuit and a lubrication pressure for a second hydraulic lubrication circuit. The arrangement also includes a control valve connected between a pump outlet of the pump and the two hydraulic circuits and has two different switching positions. The control valve, depending on the switching position, acts as a hydraulic connection between the pump and the system circuit or between the pump and the lubrication circuit.

A drive unit includes a motor, a torque converter, a torque transmission member, first and second transmission paths, first and second gear trains, and a controller. The torque converter amplifies torque directed in a first direction. The first transmission path transmits torque through the torque converter. The second transmission path transmits torque without through the torque converter. The first gear train outputs torque directed in the first direction as forward torque. The second gear train outputs torque directed in the first direction as reverse torque. The controller executes a first forward moving mode such that the motor is rotated in the first direction, and torque is outputted through the first transmission path and the first gear train. The controller executes a second forward moving mode such that the motor is rotated in a second direction, and torque is outputted through the second transmission path and the second gear train.