Sheet feeder having an intermittent coupling member

#(a) Field of the Invention

#The present invention relates to a sheet feeder having an intermittent coupling member and, more particularly, an improvement of a sheet feeder suitable for use in an imaging device such as a printer. The present invention also relates to a method for controlling such a sheet feeder and a cut-out gear suitable for use in the sheet feeder.

#(b) Description of the Related Art

#The above and other objects, features and advantages of the present invention will be more apparent from the following description, referring to the accompanying drawings.

#FIG. 1 is a schematic perspective view of a conventional sheet feeder used in a printer;

#FIG. 2 is a schematic side view of a printer comprising a sheet feeder according to a first embodiment of the present invention;

#Referring to FIG. 2, the printer generally designated by numeral 10 comprises a sheet feeder 16 according to a first embodiment of the present invention, a pair of sheet feed roller 11 and press roller 12 for transferring a cut sheet supplied from the sheet feeder 16, and a carriage 18 mounting thereon a printing head for printing data on the cut sheet supplied from the pair of rollers 11 and 12.

#The sheet feeder 16 comprises a sheet loader 15 for mounting thereon a sheet pile or pile of cut sheets 14, a pickup roller 13 for transferring the top cut sheet disposed on top of the sheet pile 14, a spring 17 for urging or thrusting the sheet loader 15 together with the sheet pile 14 against the pickup roller 13, and a gear train (not shown in FIG. 2) for controlling the operation of the sheet feeder 16.

#Referring to FIG. 3, the gear train 20 in the sheet feeder 16 comprises a roller gear 30, driven by a feed motor or drive motor 29, for rotating the sheet feed roller 11 and the press roller 12, a sun and planet gear including a sun gear 22 driven by the roller gear 30, an idle gear 25 and a planet gear 23, a timing gear 21 driven by the sun and planet gear, a cam gear 26, driven by the timing gear 21, for controlling a cam 27, and a pickup roller gear 28, driven by the timing gear 21, for rotating the pickup roller 13.