Plural mode recirculating document handler

Claim 1

In a recirculating document handler for plurally recirculating simplex or duplex original document sheets to and from a stack thereof to and from the imaging station of a copier for providing precollation copying, with plural-mode document recirculation loop path means and path selector means therein providing selected different document recirculation loop paths, depending on a selected copying mode, including an oval loop recirculation path over said imaging station having two inverting loop paths, one at each end of said oval loop, and means for selectably feeding document sheets into and out of said oval recirculation path after at least partial circulation therein, the improvement wherein: said oval document recirculation loop path includes an integral alternative S-shaped document recirculation path for returning duplex documents to said imaging station for immediately copying the opposite sides thereof before return to said stack, wherein said S-shaped document recirculation path comprises both of said inverting loop paths and a bypass path transversely intersecting said oval loop providing an alternate path connecting between opposite ends of said two inverter loop paths and forming the central portion of said S-shaped path, and wherein for said S-shaped document recirculation path the duplex documents are reversed in one of said two inverting loop paths and fed through said bypass path to said other inverter loop path and then to said imaging station, and wherein alternatively a duplex document sheet may be unidirectionally fed through said one inverting loop path, rather than reversed therein, for direct, inverted, return to said stack.