Control method for a digital copier in a two-sided document copy mode

Abstract

In a digital copier operable in a two-sided copy document mode using an automatic document feeder (ADF), when the two-sided document copy mode is selected, a second side of a two-sided document is read, and the resulting image data are written to storing means which can accommodate image data representative of two documents. Subsequently, a first side of the document is read and stored while, at the same time, the image data representative of the second side are read out and printed by the printer. Then, image data representative of the first side are read out and printed out. Hence, the document can be replaced before the preceding side is fully copied. This eliminates the extra period of time otherwise consumed by the replacement of documents. As a result, the occupancy time of the copy is reduced as a whole, promoting the efficient operation of the copier. Furthermore, one of two different kinds of interrupting means is freely selectable, so that the scanner and printer can be used independently of each other on the basis of the kind of interruption. Hence, even when a two-sided document copy mode using an ADF should be interrupted, image data representative of the second and first sides of a two-sided document can be continuously printed out since they are stored in the storing means. This also reduces the overall time loss of the digital copier.