Patent ID: 8317091

Claim:
A sheet processing apparatus for executing sorting processing of sheets, comprising: an operation unit which is used to input a ratio of good bills or bad bills; a data storage unit which stores data indicating a ratio of good bills or bad bills with respect to a reference value used to discriminate whether a sheet is a good bill or a bad bill; a decision unit which decides a reference value that attains the ratio inputted by the operation unit based on the data stored in the data storage unit; a pick-up unit which sequentially picks up sheets set in a feeder unit; a convey unit which conveys the sheet picked up by the pick-up unit; a discrimination unit which detects a degree of contamination/damage on the sheet conveyed by the convey unit, and discriminates whether the sheet is a good bill or a bad bill by comparing the detected degree of contamination/damage with the reference value decided by the decision unit; and a stacking unit which comprises a first stacker that stacks sheets discriminated as good bills by the discrimination unit and a second stacker that stacks sheets discriminated as bad bills by the discrimination unit.