An apparatus is provided for operating a segmented sliding overhead door (6). The door (6) slides in a pair of side tracks (4) mounted at either side of the door (6) between a closed vertical position (6A) and an open horizontal position (6B). A driver (1A) is mounted at the side-to-side center of the door (6) and extends away from an interior side (6C) of the door (6). The driver (1A) includes a screw drive shaft (17) mounted horizontally above the door (6). A motor (10) engages drive shaft (17) and provides reversible rotational drive force to the drive shaft (17). A drive shaft coupling unit (45) moves along the drive shaft (17) and guides the coupling unit (45) along the drive shaft (17). A door connecting rod assembly (5A) jams the door (6) against the floor when the door (6) is in the closed position (6A), and connects a carrier unit (40) to the door (6) for moving the door (6) along the side tracks (4). A safety release (61) may be included for releasing the connecting rod assembly (5A) from the door (6) so that the door (6) may be manually operated. The apparatus is particularly shock resistant.