| 摘要 |
PURPOSE:To obtain a proper toner concn. by feeding an original after detecting the density from a density standard pattern provided in the upstream side of an original carrying belt and comparing this density with the density obtained from an original to correct the toner concn. CONSTITUTION:A reference density pattern M is provided on a carrying belt 18; and when a detecting sensor 21 detects this pattern, a photosensitive body 1 is turned in the same speed as the carrying belt 18 and is electrostatically charged by an electrifier 2. When the detecting sensor 21 is operated, an original P is fed between a platen glass 6 and the belt 18 by rolls 19, and a picture pattern is formed as a latent image following the density pattern M on the photosensitive body 1 by an optical system 7. The density pattern M and the picture pattern are developed by a device 12 and are transferred to a paper P by a device 4, and the paper P is separated and is sent to a fixing part omitted in the figure. The density of the toner remaining on the photosensitive body 1 is detected by a device 16 and is compared with the density of the reference density pattern M by a control part omitted in the figure to adjust the toner concn. of the developing part 12. Thus, the reference pattern M is not displayed on the paper, and a proper density is obtained. |
