Abstract: According to a method and apparatus for multiple sheet detection for a sheet in a printing press capable of performing multiple sheet detection at a first feed operation timing which can stop feeding of the sheet to the printing press, a second feed operation timing immediately before the start of feeding of the sheet is determined. Multiple feed detection of the sheet again is performed at the determined second feed operation timing. A print stop control output is supplied to the printing press when multiple sheet feeding is detected at the determined second feed operation timing.

Abstract: According to a method and apparatus for multiple sheet detection for performing ON/OFF control of a multiple sheet detection function for sheets on the basis of use/non-use information set by keys (8), sheet data is fetched (5, 201) from one sheet fed for the first time. It is determined (5, 202) on the basis of the fetched sheet data whether multiple sheet feeding of the sheets can be discriminated by the multiple sheet detection function. A use/non-use state is checked (5, 204) by the keys when multiple sheet feeding can be discriminated by the multiple sheet detection function. An alarm is generated (205) on the basis of a check result.