An actuator is provided which includes a star compound gear train; a housing which houses said star compound gear train, said housing terminating in a back wall, wherein said back wall has an indentation defined therein; and a bearing assembly which includes first and second races and a plurality of bearings, wherein said first race is disposed in said indentation.

An actuator is provided which includes a star compound gear train; a housing which houses said star compound gear train, said housing terminating in a back wall, wherein said back wall has an indentation defined therein; and a bearing assembly which includes first and second races and a plurality of bearings, wherein said first race is disposed in said indentation.

A power transmitting apparatus for a vehicle achieves seven forward speeds with a minimal number of input gears disposed on input shafts, since the second speed gear and the fourth speed gear are simultaneously engaged with the second input gear and the third speed gear and the seventh speed gear are simultaneously engaged with the third input gear, and distortion of step ratios at the high-speed region may be prevented.

An alternator driving apparatus for driving an alternator may include a crank pulley mounted on a crank shaft of an engine, an alternator pulley connected to the crank pulley through a driving belt, an alternator shaft connected between the alternator and the alternator pulley, and a rotation speed varying mechanism configured to vary a rotation speed of the alternator shaft.

An alternator driving apparatus for driving an alternator may include a crank pulley mounted on a crank shaft of an engine, an alternator pulley connected to the crank pulley through a driving belt, an alternator shaft connected between the alternator and the alternator pulley, and a rotation speed varying mechanism configured to vary a rotation speed of the alternator shaft.

A bicycle shifting device includes a first transmission unit, a second transmission unit, a coupling member and a release unit. The first transmission unit includes a first rotational body, to which human power is transmitted. The second transmission unit includes a second rotational body coupled to the first rotational body and a rotational shaft rotatably supporting the second rotational body. The coupling member is movable relative to the second rotational body in an axial direction of the rotational shaft and configured to couple the second rotational body and the rotational shaft so that the human power transmitted from the first transmission unit is transmitted to the rotational shaft through the second rotational body. The release unit uncouples the second rotational body from the rotational shaft by moving the coupling member in the axial direction using the human power transmitted from the first transmission unit.

A bicycle shifting device includes a first transmission unit, a second transmission unit, a coupling member and a release unit. The first transmission unit includes a first rotational body, to which human power is transmitted. The second transmission unit includes a second rotational body coupled to the first rotational body and a rotational shaft rotatably supporting the second rotational body. The coupling member is movable relative to the second rotational body in an axial direction of the rotational shaft and configured to couple the second rotational body and the rotational shaft so that the human power transmitted from the first transmission unit is transmitted to the rotational shaft through the second rotational body. The release unit uncouples the second rotational body from the rotational shaft by moving the coupling member in the axial direction using the human power transmitted from the first transmission unit.

A cylindrical transmission includes a housing, an input shaft and an output shaft. The housing includes several circular discs having outside lips, the input shaft and the output shaft being provided on centre lines of the circular discs. The driving gears are provided on the input shaft; and a rotary disc having internal teeth is provided on the output shaft. Several gear shafts are provided between two adjacent circular discs, the gear shafts are located on the outer peripheries of the driving gear between the two adjacent circular discs, several gears are provided on each gear shaft, the gear shaft is adjacent to the rotary disc, one of the several gears is separated from or engaged with the rotary disc internal teeth, and all the circular discs are connected to each other via the outside lips.

A cylindrical transmission includes a housing, an input shaft and an output shaft. The housing includes several circular discs having outside lips, the input shaft and the output shaft being provided on centre lines of the circular discs. The driving gears are provided on the input shaft; and a rotary disc having internal teeth is provided on the output shaft. Several gear shafts are provided between two adjacent circular discs, the gear shafts are located on the outer peripheries of the driving gear between the two adjacent circular discs, several gears are provided on each gear shaft, the gear shaft is adjacent to the rotary disc, one of the several gears is separated from or engaged with the rotary disc internal teeth, and all the circular discs are connected to each other via the outside lips.

An alternator driving apparatus for driving an alternator may include a crank pulley mounted on a crank shaft of an engine, an alternator pulley connected to the crank pulley through a driving belt, an alternator shaft connected between the alternator and the alternator pulley, and a rotation speed varying mechanism configured to vary a rotation speed of the alternator shaft.