Transport/stacker module for mail processing system

In a mail sorting system, a transport/stacker module comprises a plurality of mailpiece carriers included in a conveyor moving in an endless serpentine path through a plurality of distributed sorting sites. Each carrier is provided with a door at each of the longitudinally carrier ends, which are opened to permit the raking of mailpieces from laterally arranged compartments of the carrier into underlying bins at the sorting sites by selectively actuating separate rakes of a rake mechanism stationed at each sorting site. The carrier doors are constructed to provide longitudinal extensions of the carrier floor, thereby minimizing the spacing between the carriers in the conveyor while preserving a requisite interior longitudinal dimension of the carrier when the doors are closed.