Patent ID: 8136671

Claim:
A document sorting machine comprising: an elongated stacker section having two ends, said elongated stacker section comprising: a transport extending through said stacker section; a plurality of sort pockets positioned along said transport; two feeder sections, one at each end of said elongated stacker section for feeding documents onto said transport of said stacker section from both of said ends of said stacker section; wherein said elongated stacker section includes: an induction buffer unit at each said end of said elongated stacker section for preventing a collision between documents being fed onto said transport from said two feeder sections; wherein said induction buffer unit comprises: a turn-around pulley at a respective end of said stacker section and forming part of said transport; a purge pocket upstream of said turn-around pulley; and a gate to divert a document from said transport into said purge pocket to prevent a collision with a document being fed onto said transport at a point downstream of said turn-around pulley.