PURPOSE: To convey a sheet paper which has been stopped once at an exact timing regardless of the thickness of the sheet paper by controlling a driving amount with a driving means according to the thickness of the paper sheet detected by a sheet thickness detection means.

CONSTITUTION: When a paper sheet P is conveyed and fed to a register roller 17 through a conveyance roller 31, the thickness of the paper sheet P is detected by a distance measuring sensor 33. Based on the measuring results, the time necessary to make the conveyance roller 31 stop after the paper sheet P is brought into contact with the register roller 17 is controlled. In the case of a thin paper sheet, for example, the time necessary to stop the conveyance roller 31 is controlled so as to be lengthened. In the case of a thick paper sheet, the time necessary to stop the conveyance roller 31 is controlled so as to be shortened. As a result, the force where the end of the paper sheet P works upon the register roller 17 is constant regardless of the thickness of the paper sheet, thus eliminating time lag of conveyance start, its advance and so on.