| 摘要 |
PURPOSE:To decide the abnormality of a sensor. etc., which is not originally subjected to a diagnosis in an image forming device which can quickly and accurately diagnose a fault. CONSTITUTION:The fuzzy quantitative value of a parameter changed by a deterioration quantity at each fault diagnostic timing set in advance is stored, so that the quantitative value is read at each diagnostic timing. On the other hand, state data detected by sensors 1a, 1b, and 1c is turned into the fuzzy quantitative value, and the presence of the fault is decided with the fuzzy quantitative value. Consequently, when the fault is absent, a deteriorated state is diagnosed by using the parameter value changed by the deterioration value as an initial value. When the fault is absent and the diagnostic result and the fuzzy quantitative value of the state data are not in coincidence, a fact that there may be any abnormality, for instance, the abnormality of the sensor, etc., is informed. |
