Toner replenishment determination device of an image forming apparatus

An image forming apparatus for forming an electrostatic latent image on an image supporting body, comprising:

• a developing device that develops an electrostatic latent image via a two-component developer that includes a toner and a carrier;
• a toner density detection device that detects a toner density;
• and
• a control device that acquires a number of write pixels from inputted image data and includes a pixel replenishment control and a sensor replenishment control,
• wherein the sensor replenishment control determines a sensor replenishment amount based on information from the toner density detection device,
• wherein the pixel replenishment control determines a pixel replenishment amount based on the acquired number of write pixels,
• wherein the number of write pixels are divided into line section write pixels based on character section data and solid section write pixels based on pictographic image data,
• wherein the pixel replenishment control determines an upper limit value of an amount of the toner to be replenished to the developing device based on a ratio between the line section write pixels and the number of write pixels, and wherein the relationship between the number of write pixels and the upper limit value of the toner replenishment amount is calculated so as to reduce the upper limit value of the toner replenishment amount when the number of write pixels is large.

An image forming apparatus for forming an electrostatic latent image on an image supporting body, comprising:

• a developing device that develops an electrostatic latent image via a two-component developer that includes a toner and a carrier;
• a toner density detection device that detects a toner density;
• and
• a control device that acquires a number of write pixels from inputted image data and includes a pixel replenishment control and a sensor replenishment control,
• wherein the sensor replenishment control determines a sensor replenishment amount based on information from the toner density detection device,
• wherein the pixel replenishment control determines a pixel replenishment amount based on the acquired number of write pixels,
• wherein the number of write pixels are divided into line section write pixels based on character section data and solid section write pixels based on pictographic image data,
• wherein the pixel replenishment control determines an upper limit value of an amount of the toner to be replenished to the developing device based on a ratio between the line section write pixels and the number of write pixels, and
• wherein the relationship between the number of write pixels and the upper limit value of the toner replenishment amount is calculated so as to increase a lower limit value of the toner replenishment amount when the number of write pixels is small.

An image forming apparatus for forming an electrostatic latent image on an image supporting body, comprising:

• a developing device that develops an electrostatic latent image via a two-component developer that includes a toner and a carrier;
• a toner density detection device that detects a toner density;
• and
• a control device that acquires a number of write pixels from inputted image data and includes a pixel replenishment control and a sensor replenishment control,
• wherein the sensor replenishment control determines a sensor replenishment amount based on information from the toner density detection device,
• wherein the pixel replenishment control determines a pixel replenishment amount based on the acquired number of write pixels,
• wherein the number of write pixels are divided into line section write pixels based on character section data of a line section and solid section write pixels based on pictographic image data of a solid section,
• wherein the pixel replenishment control determines an upper limit value of an amount of the toner to be replenished to the developing device based on a ratio between the line section write pixels and the number of write pixels,
• wherein the amount of toner to be replenished is increased with an increase of the ratio between the number of line section write pixels and the number of write pixels, and
• wherein the ratio between the line section write pixels and the number of write pixels is multiplied by a ratio of a toner adhesion amount of the solid section and a toner adhesion amount of the line section.