Patent ID: 7708664

Claim:
A drive unit for oscillatingly driven mowing sickles comprising: a first transmission unit having a first housing defining a first axis, a rotor rotationally supported in the first housing around the first axis, a first internal gear wheel retained in the first housing, said first internal gear wheel providing internal teeth, a pinion rotationally supported in the rotor around a second axis, said second axis is radially off-set to the first axis, said pinion forms an output element of the drive unit and meshes with teeth of the first internal gear wheel; a second transmission unit having an output non-rotationally connected to the rotor of the first transmission unit, said output formed as a step-down gear; a motor having an output shaft rotationally driving the second transmission unit, said motor providing a rotational speed which is reduced by the second transmission unit, formed as a step-down gear, to a rotational driving speed of the first transmission unit; said second transmission unit further comprises a planet carrier, non-rotationally connected to the rotor of the first transmission unit and rotating with the rotor around the first axis and said planet carrier carries at least one planet gear with external teeth, said at least one planet gear is rotationally supported on the planet carrier around a third axis, said third axis is radially off-set to the first axis, a second internal gear wheel stationary held and provided with internal teeth which mesh with said at least one planet gear; a sun gear meshing with said at least one planet gear; and the output shaft of the motor rotationally drives the sun gear of the second transmission unit.