| 摘要 |
PROBLEM TO BE SOLVED: To provide a highly reliable image forming device capable of preventing miss copying by providing a sorting device more improved operability. SOLUTION: By a sorting/gathering means, during the copying operation selecting a sorting or stacking mode, a document jamming by an automatic document feeder 17 occurs, and in the case a copying paper sheet being previously fed by a paper feeding unit 11 becomes to the invalidated copying paper sheet, the copying operation is controlled by a main body control section 1 so as to discharge the invalidated copying paper sheet on a bin tray of a sorting device 18, while to prohibit the copying operation, unit when the paper sheet absent is detected by the paper sheet present/absent detection mechanism 36 as for the invalidated copying paper sheet. In such a manner, coexistence of validate paper and invalidated paper can be prevented. |
