Apparatus for stacking documents in sequence

Abstract

Documents are stacked on edge on a bed assembly having a backplate assembly near one end and a slidable backstop assembly aranged to be incremented away from the backplate assembly as the documents fill the stacking space therebetween. The backstop assembly is fixed to and alternately freed from the bed assembly by an escapement assembly coupled therebetween and actuated electrically. Preferably the escapement assembly comprises a pawl and ratchet together with cogged or spurred belts guiding the backstop assembly along the bed assembly. A photoresponsive, or like, assembly is arranged to sense the entrance of documents into the stacking space, and electric reed switches and corresponding actuating magnets are assembled on the backstop and bed assemblies for predetermining an initial increment of stacking space. Electric control circuitry is connected to the photoresponsive assembly and the reed switches and to the escapement assembly for actuating the latter in successive steps as the documents fill the stacking space. Preferably, the electric control circuitry is arranged to count pulses representative of individual documents encountered in the interval in which the initial increment of stacking space is filled. This count is transferred to counter circuitry for storing a number proportional to the number of documents originally counted, which stored number is used subsequently for actuating the escapement assembly and advancing the backstop assembly as subsequent documents are received.