Abstract: This invention relates to a drive assembly for a roller door. In one form the drive comprises a motor for driving the door outputting drive via a first gear form, a means for manually driving the door outputting drive via a second gear form; a means of selecting either of the manual or motor drive for the door, a door curtain carrying wheel having a third gear form via which the wheel can be driven, where each of the first, second and third gear forms is or drives via one of a sun gear, an annulus gear, or the planet carrier of an epicycle gear box.

Abstract: A clutch driving structure coupled to a driving motor comprises a retarder (3), a clutch (4), an electronic pedometer (5), and a door position controller (6) mounted inside a housing (2) on the driving motor (1). By coupling the above-mentioned components with the driving motor (1), the transmission apparatus of the roller door is provided with convenient disassembly and maintenance. Besides, the conventional components for controlling and switching the clutch are integrated into the driving motor to constitute the transmission mechanism, and a wireless controller is also applied to obviate the manual clutch control and provide the simple, quick, accurate, and secure control.