| 摘要 |
PURPOSE: To detect abnormality of a sheet discharge sensor at an early stage by repeatedly detecting residue of sheets by the sheet discharge sensor in the case of judging the number of door opening and closing for maintenance to be less than the specified number and judging that there is an error with the sheet discharge sensor in the case when the opening and closing number is more than the specifies number. CONSTITUTION: A paper leaving alarm is generated by a control part 136 in the case when it is judged that an output level from a light receiving element 134B is higher than a specified threshold value level, a sheet discharge sensor 134 is switched on and sheets reside in a sheet discharge passage. Thereafter, as a door switch 144 is switched on when a door for maintenance provided on a frame body is opened and the door worked to remove the resided sheets in the sheet discharge passage is closed, the opening and closing number of a door 142 is checked before confirming motion of existence of the residual sheets through the sheet discharge sensor 134 at this time, and in the case when the opening and closing number is more than the specified number A, it is judged that there is an error with the sheet discharge sensor 134 and it erroneously detects residue of the sheets. |
