| 摘要 |
PROBLEM TO BE SOLVED: To prevent the waste of an unnecessary recording material due to defective protection of a device and carriage of the recording material by providing a memory to record the job history of the frequency of achieving the sequences, and judging the service life of a paper sheet feed roller by a judging means to judge whether or not the frequency exceeds the set value. SOLUTION: Jam sensors to detect abnormal carriage of a recording material are installed on a recording material carrying passage, i.e., jam sensors CP1-CP4 are installed on an upstream carrying part 4 of the recording material. When abnormal carriage of the recording material is detected during the image forming sequence by the jam sensors CP1-CP4, a device stops the image forming sequence, and inform a user of it. When the delay frequency of the recording material is increased due to degradation of the carrying ability of a retard roller RL1 which is a recording material feeding means as an image forming device is used, and the predetermined ratio is realized in achieving the m-th frequency job, the request for the replacement of the retard roller RL1 is displayed on an operation part of the image forming device. |
