After connecting the power, the motor occurs electromagnetic torque, while the double-brake attracts. The rotor starts rotation at the speed 2850rpm/min, through the coupler, rotor's speed and torque input to the gearbox, after reduction of speed ratio from the gearbox, through the drive adapter, the torque was passed by an outer shaft to the outer tube. thus, the outer tube's rotation controls the door or window up and down.

The rotation of the outer tube enables the crown and gear ring's rotation, through the middle support pole(inside of the limit head) tooth profile nut slide up and down, at the help of the limit head block it can control microswitch open or close finally realize control the limitation up or down. If cut the power, double-brake braking, motor stop working.