Patent ID: 8730531

Claim:
An automatic document feeding scanning device, capable of scanning a document, wherein the automatic document feeding scanning device comprises: an automatic document feeder, capable of feeding the document, and having a pickup arm, a top cover and a feeding gear, wherein the feeding gear connects with the pickup arm and is capable of being driven, so as to enable the pickup arm to feed the document into the automatic document feeder or to be swung relative to the top cover, while the top cover is disposed over the pickup arm; a flatbed scanner, disposed under the automatic document feeder, capable of scanning the document, and having a scanning module, an obstructing element and a scanning gear, wherein the scanning gear connects with the scanning module and capable of being driven, so as to enable the scanning module to be moved and thus to scan the document, while the obstructing element is disposed at a side of the scanning module and capable of obstructing the scanning module to be moved; and a power switching mechanism, disposed at a position near the automatic document feeder and the flatbed scanner, and capable of transmitting a driving power to the automatic document feeder or transmitting the driving power to the flatbed scanner, wherein the power switching mechanism comprises: a driving module, capable of providing the driving power and outputting the driving power; and a planet gear module, connecting with the driving module, and capable of engaging with the feeding gear and thus transmitting the driving power to the automatic document feeder, or engaging with the scanning gear and thus transmitting the driving power to the flatbed scanner, wherein the obstructing element provides a first reacting force to the scanning module and the planet gear module when a movement of the scanning module is obstructed by the obstructing element, so as to enable the planet gear module to be disengaged from the scanning gear, while the top cover provides a second reacting force to the pickup arm and the planet gear module when a swing of the pickup arm is obstructed, so as to enable the planet gear module to be disengaged from the feeding gear.