Output module for an advanced letter sorter

In order to improve the quality of mail piece stacking, an engineering model of an output module has been developed and tested by DETECON and FHG-IML under the master agreement between DETECON and the United States Postal Service in an R and D - project. The origin of the technical approach for this output module was a concept for an Advanced Letter Sorter with a multilevel transporter, that required a horizontal output stacker. One output module has to reach up to four different levels of the transporter so that the vertical space required by the output stacker had to be minimized. Considering the heterogeneous composition of manual letter mail and its differing physical characteristics, a nearly form-locking transfer of mail pieces between transporter carriers and stack was favoured. As a consequence, the transmission had to be effected with minimal friction influences. This paper describes the functional principle, the main components of the output module, and the results and parame ters of several tests.