| 摘要 |
PURPOSE:To always obtain stable image quality without the occurrence of defective transfer with the stain of charging wire, etc., by developing a reference density pattern onto an electrostatic latent image carriers detecting the density of a batch image transferred on a transfer belt and that of a batch image transferred on the electrostatic latent image carrier with a first and a second detecting means respectively, comparing them with a reference value, and adjusting an output from a belt electrifying means. CONSTITUTION:After the reference density pattern 18 is exposed on the electrostatic latent image carrier 2 by an exposure means 15, and is developed by a developing means 3, this image is transferred onto the transfer belt 5. The density of the transferred batch image is detected by a first sensor 19 while the density of the batch image which was not transferred onto the transfer belt 5 remains on the electrostatic latent image carrier 2 is detected by a second sensor 20. A control means 21, for which the detected densities are inputted, compares its ratio with the previously set reference value, and adjusts the output from the belt electrifying means 6 based on the result. Thus, stable image quality is always obtained without the occurrence of defective transfer, which is caused with the stain of the charge wire, etc. |
