Patent ID: 7520505

Claim:
In a sheet stacking system in which non-rigid print media sheets are: sequentially ejected from a sheet ejection position to drop onto an underlying stack of other such non-rigid print media sheets to be superposed thereon, there is provided a sheet stacking assistance system comprising: a system for providing a signal that the trailing edge of a print media sheet is being ejected from said sheet ejection position, a rack and gear driven print media sheet trailing edge knockdown system activated in response to said signal that the trailing edge of a print media sheet is being ejected from said sheet ejection position, said print media sheet trail edge knockdown system moving substantially linearly downwardly from above said sheet ejection position and past said sheet ejection position to engage a trailing edge area of said ejected print media sheet to rapidly push said print media sheet rapidly downwardly towards said underlying stack of other such non-rigid print media sheets, said print media sheet trail edge knockdown system then automatically rapidly reciprocally lifting up away from said print media sheet to above said sheet ejection position before a subsequent said sequential ejection of a print media sheet from said sheet ejection position.