Abstract: A door opener system which includes a compact unit containing a motor, circuitry and various accessories, which can be quickly connected to and disconnected from the operator system, said motor having a first gear which easily is positioned into a meshing relationship with a second gear upon connection of the compact unit to the operator system. The operator system further includes the use of only two common switch actuators for operating the motor to move the door in open and closed positions, and to stop the motor upon the door striking an obstruction in its path of travel, said actuators being cooperatively associated with a cam actuator and drive chain pressure responsive means. Also, a unitary gear and drive sprocket structure is utilized in the drive system. Finally, an adjustable shock absorber type draw bar interconnects the door to the chain drive.