Abstract: The invention concerns an operator assembly for a movable barrier. The operator assembly includes a motor with a motor output shaft, an output drive to transfer drive to the movable barrier, and a transmission assembly to transfer drive from the motor output shaft to the output drive. The output drive is rotatable in a clockwise direction and in a counterclockwise direction, depending on whether the movable barrier is closing or opening. The output drive comprises a crown wheel rotatable about an output drive axis centre of rotation and having an outer face provided with a plurality of attachment points spaced from said centre of rotation.

Abstract: The invention provides an operator assembly for a movable barrier comprising a roller closure, the roller closure mounted on a rotating carrier assembly, the operator assembly including a motor with a motor output shaft, an output drive to transfer drive to the movable barrier, and a transmission assembly to transfer drive from the motor output shaft to the output drive, the output drive rotatable in a clockwise direction and in a counterclockwise direction, depending on whether the movable barrier is closing or opening, wherein the output drive comprises a rotating crown wheel with an outer face carrying a plurality of shaped attachment portions, each attachment portion configured to receive an output drive extension element to engage with a drum wheel comprised in said rotating carrier assembly, the operator assembly including at least one first output drive extension element of a first size and shape and at least one second output drive extension element of a second, different size and shape, each first an