Sheet feeder and scan apparatus with sheet-stopping function independent of movement of pick-up mechanism

A scan apparatus, comprising:

• an image-reading module;
• a sheet-transporting mechanism;
• a paper tray;
• and
• a sheet feeder for picking up and feeding a sheet from the paper tray to the sheet-transporting mechanism, wherein the sheet-transporting mechanism transports the sheet past the image-reading module, the image-reading module acquires an image of the sheet, and the sheet feeder comprises:
• a rotating shaft, rotatable in a first direction and a second direction;
• a pick-up mechanism, for picking up the sheet from the paper tray, comprising a bracket mounted on the rotating shaft and a pick-up roller mounted on the bracket;
• a sheet-input roller, mounted on the rotating shaft, for feeding the sheet to the sheet-transporting mechanism;
• and
• a sheet-stopping mechanism, driven independent of movement of the bracket by the rotating shaft, switching between a sheet-stopping state and a sheet-non-stopping state, the sheet-stopping mechanism comprising:
• a driving member, mounted on and rotated with the rotating shaft;
• a shutter, wherein the driving member actuates the shutter to advance and retract, and the shutter comprises:
• a first body, pivotally mounted on a pivot pin, interacting with the driving member;
• and
• a second body linked to one end of the first body, advancing and retracting as the driving member is rotated with the rotating shaft;
• and
• a torsion spring, pivotally mounted on the pivot pin and having one end fixed, providing a resilient force to the first body and facilitating returning the first body to the sheet-stopping state, wherein:
• the rotating shaft rotates in the first direction to enable the sheet-stopping mechanism to enter the sheet-non-stopping state in which the sheet is allowed to come into contact with the sheet-input roller;
• and
• the rotating shaft rotates in the second direction to enable the sheet-stopping mechanism to enter the sheet-stopping state in which a passage to the sheet-input roller is blocked up.