Patent ID: 9278820
Filing Date: 2016-03-08
CPC Classification: B65H

Claim Text:
1. A sheet stacking device comprising: a sheet stacking portion configured to stack a plurality of sheets thereon, the sheet stacking portion being supported to be movable in an up-down direction; an electric motor configured to output, to the sheet stacking portion, a driving force for moving the sheet stacking portion in the up-down direction; a current detecting portion configured to detect a current value of the electric motor; an abnormality determining portion configured to determine that the sheet stacking portion is in an abnormal state when the current value detected by the current detecting portion is greater than a predetermined threshold; and an updating portion configured to update the predetermined threshold based on a current value that was detected by the current detecting portion while the sheet stacking portion with a predetermined set amount of sheets stacked thereon was being moved by the driving force received from the electric motor.