| 摘要 |
PROBLEM TO BE SOLVED: To accurately detect the exchange periods of consumables, without requiring a special detecting means by using functions for showing the degrees of newness of the consumables with respect to a manipulated variable. SOLUTION: In the RAM 54 of a control part 50, the set value (SC set value) of the grid voltage of a scorotron electrifier 34 in an image output part 30, the set value (LP set value) of the laser power of a laser light scanner 32 and the functions for showing the degrees of newness with respect to these SC and LP set values, of a photoreceptor 33 as the consumables are written. A CPU 51 calculates the degrees of newness with respect to the SC and LP set values when image quality is controlled by the developing patch of a reference pattern, from graphs of the functions, to calculate the product of the degrees, when the image quality is controlled. When the product is below a prescribed value, the CPU 51 decides that the photoreceptor 33 is at an exchange period and displays the fact that the exchange of the photoreceptor 33 is required in a user interface part 60. |
