Drive unit for a banknote reader

A drive mechanism for a sheet reading apparatus having an input channel, a stacking device, conveying means for conveying a sheet on a conveying path between said input channel and said stacking device, and a testing device disposed along said conveying path between said input channel and said stacking device for recognizing sheet characteristics and thereby determining whether a sheet inserted into said input channel is to be conveyed to said stacking device for deposit in said sheet reading apparatus or ejected from said sheet reading apparatus, said drive mechanism comprising

• a common drive unit which drives both said conveying means and said stacking device, said drive unit being an aggregate comprising at least first and second motors and at least first and second couplings which transmit torque produced by said first and second motors,
• said first and second couplings being arranged so that both said first and second motors are coupled to a drive axle of said conveying means for pulling a sheet through an input opening of said inlet channel and conveying it to said stacking device, at least said first motor is coupled to said drive axle of said conveying means for ejecting a sheet, and at least said second motor is coupled to a gear box of said stacking device for stacking a sheet.