| 摘要 |
PROBLEM TO BE SOLVED: To inform a user of information on the possibility of image-formation till getting to a toner insufficient state by estimating the point of time when the image-formation gets impossible based on the consumption of the toner and the number of sheets where an image is formed. SOLUTION: A toner quantity in a developing device begins as an initial toner quantity V and is gradually decreased as the image-formation is performed. When the toner quantity in the developing device shows Z1 , a nearly end state is detected by an antenna. Assuming that the number of sheets where the image is formed at such a time is P1 , the average toner consumption W per a sheet till then is obtained by W=(V-Z1 )/P1 . The image-formation can be performed by the number of sheets obtained by X=(Z1 -E)/W till attaining the toner quantity E when the toner ends. Then, such calculation is performed in a main body in the case of detecting the nearly end state, and a message 'toner is depleted when the image-formation is performed by about X sheets if the toner is consumed at such a pace' is displayed on the display part of the control panel of a printer or the display means of a connected computer, so that the user is informed of an effect. |
