A gearbox having a longitudinally-oriented input shaft for transmitting rotational force from an engine; a gear drive train, for receiving rotational force from the input shaft, which includes a plurality of meshed gear pairs mounted on first and second shafts that are laterally oriented perpendicular to the longitudinally oriented input shaft; and in one aspect a fast-change gear assembly interposed in the gear drive train for changing the torque transfer characteristics of the gearbox.

An accumulator piston configured to be situated within an accumulator bore of a housing for use in vehicle transmissions. The accumulator piston including a casing, the casing including a top surface, a bottom surface opposite the top surface, and a side wall situated between the top surface and the bottom surface, a pin guide protruding from the top surface of the casing, the pin guide including a centrally disposed aperture, the aperture configured to receive an elongated pin, and a sealing member encircling the side wall of the casing such that the sealing member covers any exposed surface of the side wall.

An engine for an aircraft includes an engine core having a turbine, a compressor, and a core shaft connecting the turbine to the compressor; a fan located upstream of the engine core, the fan having a plurality of fan blades; and a gearbox. The gearbox is an epicyclic gearbox and comprises a sun gear, a plurality of planet gears, a ring gear, and a planet carrier on which the planet gears are mounted. The radial bending stiffness of the planet carrier is equal to or greater than 1.20×10.sup.9 N/m, and/or the tilt stiffness of the planet carrier is greater than or equal to 6.00×10.sup.8 Nm/rad. A method of operation of such an engine is also disclosed.

A drivetrain for an aircraft includes an engine, a driveshaft receiving rotational energy from the engine and a gearbox including a planetary gear system receiving rotational energy from the driveshaft. The planetary gear system includes a sun gear, planet gears, a ring gear and an integral carrier forming flexured carrier posts. Each flexured carrier post supports a respective one of the planet gears and has a fixed proximal end and a cantilevered distal end. The planetary gear system includes flexured roller races, each having a fixed end and a cantilevered end. The fixed end of each flexured roller race is coupled to the cantilevered distal end of a respective flexured carrier post. The planet gears engage with the flexured roller races to rotate about the flexured carrier posts. The cantilevered ends of the flexured roller races experience cantilevered motion to absorb loads from the planet gears.

A hybrid propulsion system can include a turbomachine having a compressor, a combustion chamber, and a compressor turbine. The compressor can be connected to the compressor turbine via a first shaft. The system can include a hybrid drive assembly which can include a power turbine in fluid communication with an outlet of the compressor turbine to be driven by compressor turbine exhaust to drive a second shaft that is disconnected from the first shaft. The hybrid drive assembly can also include an electrical machine mechanically coupled to the second shaft either to convert rotational energy to electrical energy or to convert electrical energy to rotational energy of the second shaft.

A gearbox comprising: an outer intermediate shaft carrying a first set of shaft gears; an inner intermediate shaft carrying a second set of shaft gears, the inner intermediate shaft running concentrically within the outer intermediate shaft; a first lay shaft carrying a first set of drive gears and an output gear positioned along the first lay shaft between two of the first set of drive gears, a second lay shaft carrying a second set of drive gears and an output gear positioned along the second lay shaft between two of the second set of drive gears, each drive gear being coupled to a respective shaft gear to together provide a plurality of gear ratios between the intermediate shafts and the output shaft; and an output shaft, each lay shaft being coupled to the output shaft by the respective output gear.

An oil pump drive device (1) may include a housing (G), an oil pump drive shaft (AN), an electric motor, and a planetary gear set (RS). The planetary gear set (RS) may be supported by the housing (G) and have a first element (E1) connected to a rotor (R) of the electric motor, a second element (E2) connected to the oil pump drive shaft (AN), and a third element (E3) drivable by a drive source located outside the oil pump drive device (1). A first bearing (L1) may be supported on the housing (G) and may support at least one of the elements (E1, E2, E3) of the planetary gear set (RS) in a radial direction. The stator (S) of the electric motor is at least partially surrounded by a plastic mass (K), where the stator (S) is attached to the housing (G) via the plastic mass (K).

A drivetrain for an aircraft includes an engine, a driveshaft receiving rotational energy from the engine and a gearbox including a planetary gear system receiving rotational energy from the driveshaft. The planetary gear system includes a sun gear, planet gears, a ring gear and an integral carrier forming flexured carrier posts. Each flexured carrier post supports a respective one of the planet gears and has a fixed proximal end and a cantilevered distal end. The planetary gear system includes flexured roller races, each having a fixed end and a cantilevered end. The fixed end of each flexured roller race is coupled to the cantilevered distal end of a respective flexured carrier post. The planet gears engage with the flexured roller races to rotate about the flexured carrier posts. The cantilevered ends of the flexured roller races experience cantilevered motion to absorb loads from the planet gears.

A gearbox for a motor vehicle, includes multiple gears, a housing, an interior space enclosed by the housing, a gearshift clutch located in the interior space, through which a gear can be shifted, and a shifting device for transmitting an external actuating force acting outside the housing for shifting to the gearshift clutch, the shifting device having an inner shifting part in the interior space, a first introduction element which engages through a first opening provided in the housing for guiding the external actuating force to shift the gear to the inner shifting part, a shifting mass arranged outside the housing which is moved during gear shifting, and a connecting element different from the first introduction element with which the shifting mass is connected to the inner shifting part, the connecting element engaging through a second opening different from the first opening in the housing into the interior space.

The disclosure relates to a method for operating a drivetrain for a work machine, wherein a first electric motor drives a work drive of the work machine via a first transmission arrangement, wherein a second electric motor drives a traction drive of the work machine via a second transmission arrangement, and wherein, during a shift process of the second transmission arrangement from a relatively low gear ratio stage to a relatively high gear ratio stage, the rotational speed of the second electric motor is reduced. The method according to the disclosure is distinguished by the fact that, during the shift process, a driving connection is produced between the first electric motor and the second transmission arrangement by a first clutch, such that, during the shift process, the first electric motor drives the traction drive. The disclosure furthermore relates to a corresponding drivetrain and to a work machine.