| 摘要 |
PURPOSE:To prevent a main body from becoming unusable and to make it possible to continuously form a clear electrostatic latent image on the surface of a photosensitve body by controlling based on a mean value of effective control results in past plural times in the case that an accidental abnormality of an output value is generated in an optical sensor. CONSTITUTION:A control system 60 is constituted of a master CPU 40, a slave CPU 41, a ROM 42 for master CPU, a ROM 44 for slave CPU and a RAM 48. And in the case that a normal input is executed by a photodetector 52 for the optical sensor and a little difference between this input value and the preceding input value is in existence, a process feedback control is executed by a control mechanism for the control system 60 based on the input value, and then, the input value of the photodetector 52 is recorded by the RAM 48. In the case that the difference between the input value of the photodetector 52 and the preceding input value is larger than the previously set numerical value because of the trouble of the optical sensor, etc., the process feedback control is not executed by the control system 60, and the control is executed based on the mean value of each output value stored by the RAM 48 in past N times instead of the process feedback control. |
