| 摘要 |
An overhead conveyor system which comprises a rail (3a, 3b), a rotatable drive shaft (5) extending along the rail and located above the rail, and at least one carriage which is adapted to run along the rail and to support a load suspended from the carriage, which carriage is provided with at least one drive wheel (12), which is inclined relative to the longitudinal direction of the drive shaft. A spring means (14) presses the drive wheel (12) against the drive shaft (5) by spring load, and has a first spring constant during an initial depression of the drive wheel, and a second spring constant upon depression of the drive wheel more than a specific distance (L). Furthermore, a distance between a circumferential surface of the drive shaft and the rail is reduced along segments of the rail in which additional driving force is required, so that along said segments the drive wheel is depressed past said level. This allows increased driving force to be derived along said segments. |
