Single stack height sensor for plural sheet stacking bins system

Abstract

In a sheet stacking system with an array of plural sheet stacking bins with sheet entrances for stacking plural flimsy print substrate sheets from a printed sheets output path into selected bins, with a sheet feeding input path system for feeding selected sheets into a selected bin to be stacked therein, with a bin fullness indicator system for indicating that the estimated height of the stack has reached a preset allowable maximum, and a stacking control system controlled by the bin fullness indicator system to control the sheet feeding input path; there is a single stack height sensing system including a stack height sensor for respective measurements of the actual stack height of the stack of sheets in respective bins for the bin fullness indicator system, a movable carriage system for moving this single stack height sensing system from adjacent to one bin to adjacent another bin for respective measurements, the stack height sensor including a movable sensing element extendable by an intermittent actuator into the bin then adjacent to the movable carriage system to detect the stack height therein. A signal generator is responsive to the sensing element position to provide control signals to the stacking control system.