Automatic sheet feeding apparatus with clutch

Abstract

An automatic sheet feeding apparatus includes a pick-up mechanism, a sheet transporting mechanism, a power source and a clutch. The sheet transporting mechanism transports a sheet picked up by the pick-up mechanism through and out of a passageway. The power source for driving the pick-up mechanism includes a power output shaft and a first transmission gear for respectively outputting and transmitting power. The clutch includes a second transmission gear and a power coupling component. The second and first transmission gears are disposed coaxially. The power coupling component is coaxially disposed between the first transmission gear and the second transmission gear and is coupled to the first transmission gear. The power coupling component reciprocates back and forth along an axis to selectively couple and drive the second transmission gear. The second transmission gear is coupled to the pick-up mechanism, and the power source selectively drives the pick-up mechanism through the clutch.

1 . An automatic sheet feeding apparatus, comprising:
 a pick-up mechanism for picking up a sheet from a tray and feeding the sheet into a passageway;   a sheet transporting mechanism for transporting the sheet picked up by the pick-up mechanism through and out of the passageway;   a power source for driving the pick-up mechanism, the power source comprising:   a power output shaft for outputting power; and   a first transmission gear for transmitting the power; and   a clutch, which comprises:   a second transmission gear, wherein the second transmission gear and the first transmission gear are disposed coaxially; and   a power coupling component coaxially disposed between the first transmission gear and the second transmission gear and coupled to the first transmission gear, wherein the power coupling component reciprocates back and forth along an axis to selectively couple and drive the second transmission gear;   wherein the second transmission gear is coupled to the pick-up mechanism, and the power source selectively drives the pick-up mechanism through the clutch.   
     
     
         2 . The sheet feeding apparatus according to  claim 1 , wherein the pick-up mechanism comprises:
 a power input shaft; and   an input gear mounted on the power input shaft and driven to rotate the power input shaft.   
     
     
         3 . The sheet feeding apparatus according to  claim 2 , wherein the second transmission gear meshes with the input gear to transmit the power to the input gear. 
     
     
         4 . The sheet feeding apparatus according to  claim 2 , wherein the pick-up mechanism comprises:
 a separation roller mounted on the power input shaft and driven by the power input shaft to rotate; and   a pick-up roller driven by the power input shaft to rotate and move up and down.   
     
     
         5 . The sheet feeding apparatus according to  claim 1 , wherein the power source further comprises an output gear, mounted on the power output shaft and coupled to the first transmission gear, for transmitting the power to the first transmission gear. 
     
     
         6 . The sheet feeding apparatus according to  claim 5 , wherein the power source further drives the sheet transporting mechanism, the sheet transporting mechanism comprises a third transmission gear and a plurality of rollers, driven by the third transmission gear, for transporting the sheet, and the third transmission gear is coupled to the output gear. 
     
     
         7 . The sheet feeding apparatus according to  claim 1 , wherein the clutch further comprises a clutch control mechanism for moving the power coupling component back and forth along the axis to engage and disengage the power coupling component from the second transmission gear. 
     
     
         8 . The sheet feeding apparatus according to  claim 7 , wherein the clutch control mechanism comprises:
 a solenoid; and   an arm member driven by the solenoid and coupled to the power coupling component to move the power coupling component.   
     
     
         9 . The sheet feeding apparatus according to  claim 8 , wherein a piston of the solenoid drives the arm member in a direction parallel to a moving direction of the power coupling component. 
     
     
         10 . The sheet feeding apparatus according to  claim 9 , wherein the clutch control mechanism further comprises:
 a compression spring, wrapping around the piston, for providing a restoring force to the piston.   
     
     
         11 . The sheet feeding apparatus according to  claim 1 , wherein:
 the first transmission gear comprises a first internal meshing portion, wherein the power coupling component engages the first internal meshing portion; and   the second transmission gear comprises a second internal meshing portion, wherein the power coupling component in the reciprocal motion selectively engages the second internal meshing portion.   
     
     
         12 . The sheet feeding apparatus according to  claim 11 , wherein the power coupling component comprises:
 a first ratchet portion; and   a second ratchet portion; wherein the first internal meshing portion is engaged with the first ratchet portion and the second internal meshing portion is engaged with the second ratchet portion.