| 摘要 |
A gearbox 1 comprises a housing 2 surrounding a through bore 3. An input coupling 5 surrounds the through bore and is mounted for rotation relative to the housing. An output coupling 13 surrounds the through bore and is mounted for rotation relative to the housing. A sun gear 7 is fixed relative to the input coupling and a planet carrier 8 is fixed relative to the housing. A plurality of planet gears 10 are rotatably mounted on a planet carrier 8 each spaced circumferentially around the through bore and meshing with the sun gear 7. An annular gear 11 is fixed relative to the output coupling and meshing with each planet gear. The gearbox may be a reduction gearbox having a ratio in the range 0.6-0.9 and the output may rotate in the opposite direction to the input. The gearbox may comprise a shaft 4 held in the through bore which may couple to a first output where the output coupling is coupled to a second output. The gearbox may transmit torque to counter rotating propellers in a marine or airborne vessel. |
