| 摘要 |
PURPOSE: To save useless rising time to release a power save mode by preventing an unnecessary shifting state to the power save mode, when a human body is not detected, in a time zone having a high use frequency. CONSTITUTION: This image forming device is provided with a human body detecting counter for freely updatably counting the number of the detection of the human body detected by a human body detecting means 39 in every time zone in one day time unit and a time zone human body detection number storage means for storing the number of the detections of the human body in each time zone counted by the human body detecting counter by the next day. A use frequency in every time zone on that day is roughly predicted by the number of the detections of the human body in every time zone counted by the human body detecting counter, as the results of the preceding day, to be stored in the human body detection number storage means. The power save mode is set or released by a mode switching means at the beginning of the time zone on that day, based on the results of the comparison of the predicted number of the detections of the human body in every time zone and a reference value. |
