Image forming apparatus

An image forming method comprising:

• forming an electrostatic latent image on an image carrying body based on image data of a print job including a number of sheets to be printed for the print job and a pixel count of the print job;
• developing the electrostatic latent image in a developing device with a two-component developer containing toner and a carrier;
• calculating a toner replenishment time required to transport replenishment toner to the developing device based on the pixel count of the print job, and to calculate a job duration of the print job based on the number of sheets to be printed;
• and
• transporting replenishment toner during each of a plurality of divided replenishment times, wherein the total of the plurality of divided replenishment times is equal, to the toner replenishment time calculated by the calculating section, and the plurality of divided replenishment times are uniformly spread across the job duration.

An image forming apparatus comprising:

• a latent image forming section configured to form an electrostatic latent image on an image carrying body based on image data of a print job including a number of sheets to be printed for the print job and a pixel count of the print job;
• a developing device configured to develop the electrostatic latent image with a two-component developer containing toner and a carrier;
• a toner cartridge configured to provide replenishment toner to the developing device;
• a toner transporting section configured to transport replenishment toner from the toner cartridge to the developing device;
• a calculating section configured to calculate a toner replenishment time required for the toner transporting section to transport the replenishment toner to the developing device based on the pixel count of the print job, and to calculate a job duration of the print job based on the number of sheets to be printed;
• and
• a drive control section configured to control the toner transporting section to transport replenishment toner during each of a plurality of divided replenishment times that each refer to on an ON period of transportation operation performed by the toner transporting section and obtained by equally dividing the toner replenishment time length by a predetermined number, each OM period being followed by an OFF period of transportation operation, wherein the total number of ON and OFF periods of transportation operation equals the job duration, and the plurality of divided replenishment times are uniformly spread across the job duration.