Gearbox and driving device thereof

A gearbox for power lift gate including:

• a housing, a rotating frame (22/22′) arranged in the housing and rotatable relative to the housing, a sun roller (23) and a plurality of planetary gears (24) supported by the rotating frame (22/22′), an inner ring tooth (218) provided in the housing, and the planetary gears (24) being surrounded around the sun roller (23) in the central area, characterized in that:
• the sun roller (23) includes a first rod (230) with helical teeth and a second rod (232) extending coaxially from the first rod (230);
• each planetary gear includes a first gear (240) and a second gear (242) which are extending coaxially from the first gear (240) and rotate synchronously, the first gear (240) meshes with the helical teeth of the first rod (230) of the sun roller (23), and the second gears (242) mesh with the inner ring tooth (218) of the housing;
• each planetary gear (24) is installed in the rotating frame (22/22′) via a pin for driving the rotating frame to rotate, and rotating output (220) is provided on the side of the rotating frame far away from the planetary gears (24) for connecting to external loads.