Patent ID: 7889365

Claim:
An image forming apparatus comprising: an image forming section including a photoconductor drum, a charging device for uniformly charging the photoconductor drum, an exposure device for exposing the photoconductor drum so as to form a latent image, and a developing device for depositing toner onto the latent image using a developing roller to develop the latent image; a manual setting mode for enabling a user to provide instruction of timing for executing a process control of the image forming section; a cumulative operation information management section for calculating and storing cumulative operation information after the execution of the previous process control; a threshold value setting section for setting, to a threshold value, the cumulative operation information at the point when the instruction is provided in the manual setting mode; and a process control management section for executing a process control and resetting the cumulative operation information at timing when the cumulative operation information reaches the threshold value a print job determining section for determining whether the print job containing contents whose image is formed by the image forming section contains a color page or not so as to determine whether the print job is a color job or a monochrome job, wherein the image forming section includes a black image forming section used for both of color image formation and monochrome image formation, and a color image forming section used for the color image formation, the cumulative operation information management section calculates and stores the cumulative operation information in such a way the cumulative operation information is classified into monochrome cumulative operation information and color cumulative operation information in accordance with the determination at the print job determining section, the threshold value setting section sets, to a monochrome threshold value, the monochrome cumulative operation information at the point when the instruction of the process control in the monochrome mode is provided, and sets to a color threshold value, the color cumulative operation information at the point when the instruction of the process control in the color mode is provided, and the process control management section executes the process control for the black image forming section and resets the monochrome cumulative operation information at timing when the monochrome cumulative operation information reaches the monochrome threshold value, and the process control management section executes the process control for the black image forming section and the color image forming section and resets the monochrome cumulative operation information and the color cumulative operation information at timing when the color cumulative operation information reaches the color threshold value.