Evenly retractable and self-leveling nips sheets ejection system

In a sheet handling system including a supporting frame, a sheets compiling tray and a sheets ejection system, said sheets ejection system including an axial drive shaft with plural sheet drive rollers and a pivotal mounting system to which said drive shaft is mounted, said pivotal mounting system providing pivoting of said drive shaft with said plural sheet drive rollers between a first position for engaging sheets in said sheets compiling tray for sheets ejection and a second position out of engagement with said sheets in said sheets compiling tray;

• the improvement wherein:
• said pivotal mounting system provides a limited degree of freedom of movement of at least one end of said axial drive shaft on an axis of movement perpendicular to said axial drive shaft when said pivotal mounting system has pivoted said drive shaft into said first position for engaging sheets in said sheets compiling tray for sheets ejection, to provide a self-leveling more uniform sheet engagement force of said plural sheet drive rollers along said drive shaft;
• said pivotal mounting system further providing a positive constrained engagement of said drive shaft by said pivotal mounting system when said pivotal mounting system is pivoting said drive shaft into said second position to provide a more accurately centered position of said shaft by said pivotal mounting system in said second position;
• wherein at least one side of said pivotal mounting system is pivotally mounted to said supporting frame with a pivot pin, and said supporting frame has a mounting slot for mounting and laterally constraining said pivot pin in said mounting slot but providing for vertical movement of said pivot pin therein to allow said one side of said pivotal mounting system to move vertically relative to said supporting frame, and wherein said supporting frame also has at least one limited length slot providing an end stop, which limited length slot is spaced from said mounting slot, and wherein said pivotal mounting system has at least one mounting pin engaged within said limited length slot, which mounting pin is vertically movable within said limited length slot in said first position of said pivotal mounting system, but which mounting pin engages said end stop of said limited length slot in said second position of said pivotal mounting system to constrain the position of said pivot pin in said mounting slot to insure an accurately centered position of said drive shaft by said pivotal mounting system in said second position;
• and
• wherein said supporting frame has at a second limited length slot providing a second end stop, which limited length slot is spaced from the opposite side of said mounting slot, and wherein said pivotal mounting system has a second mounting pin engaged within said second limited length slot, which second mounting pin is vertically movable within said second limited length slot in said first position of said pivotal mounting system, but which second mounting pin engages said second end stop of said second limited length slot in said second position of said pivotal mounting system to center the position of said pivot pin in said mounting slot to insure an accurately centered position of said drive shaft by said pivotal mounting system in said second position.