| 摘要 |
PROBLEM TO BE SOLVED: To detect rotation without newly adding a photointerrupter, to decrease the factor of trouble caused by the reduction of the number of parts and to simplify and miniaturize the device by providing a motor rotation detecting means capable of detecting the stop state of a stepping motor by sharing a part of a recording material detection means. SOLUTION: Since a paper ejection sensor 22 is turned on while a sheet is passing through the sensor 22, the photointerrupter 20 is repeatedly turned on/off by an encoder 21. When accordion jam is caused in a paper ejection part and the 2nd stepping motor is stopped, a paper ejection roller 18 is stopped and the rotation of the encoder 21 is also stopped. At such a time, the photointerrupter 20 is still in an on-state. When a control circuit continues to receive an on-signal from the photointerrupter 20 for a fixed time or more, it judges that the 2nd stopping motor is stopped, so that the high voltage of a primary electrifier and a transfer electrifier is made low and the local electrification of a photoreceptor 14 is prevented. |
