| 摘要 |
PROBLEM TO BE SOLVED: To provide an automatic document feeder capable of obtaining many kinds of discrimination available document sizes, with a simple constitution by eliminating a cause of variance in a read value in a document size, and properly discriminating the document size by suppressing the variations in the read value in the document size due to the slip and deflection of a document during carrying. SOLUTION: In the automatic document feeder 100, a controller 50 is provided with a pulse generating part 50a for outputting pulse signals, in synchronization with the operation of a motor for carrying the document, a pulse counter 50b for counting the pulse signals, based on detection signals from document size detecting sensors 40a and 40b provided to be away from each of other on the upstream and downstream sides of a carrying path and a document size discriminating part 50c for executing the correction processing of a count value obtained by counting with a prescribed pulse counting procedure, to discriminate the document size. |
