| 摘要 |
PROBLEM TO BE SOLVED: To accurately detect paper remains inside an image forming apparatus and a sheet material conveying device without increasing the number of optical sheet sensors.SOLUTION: A nip part is formed by an intermediate transfer belt 51 and a secondary transfer roller 57. The nip part is applied with transfer voltage for accelerating transfer of a toner image. In a state where the nip part holds or does not hold recording paper P, transfer current is measured, and the measured transfer current is taken as a reference value. The reference value is compared with an actually detected current value so as to determine if the recording paper P remains in the nip part. |
