| 摘要 |
PURPOSE:To maintain the amt. of the toner to be adhered at a prescribed specified level by transferring the toner on a conductive roll which rotates in contact with the donor, irradiating light thereto, and changing the press contacting force of a doctor blade, which regulates the supply rate of the toner to the donor, with the donor according to the information on the amt. of the toner to be adhered relating to the varying magnitude in the quantity of the light reflected therefrom. CONSTITUTION:The transfer voltage by an electric power source 2 is applied by the operation of a switch 4 to a conductive roll 1 to transfer a toner T from a donor roll 10. The light of a light emitting element 4a is irradiated to the toner T on the roll 1, and the reflected light thereof is detected with a photodetector 4B and is amplified with an amplifier 5, whereafter a pressure control device 6 is operated to control the press contact force of a doctor blade 204. The amt. of the toner T to be stuck on the donor 101 is controlled at a prescribed level by such feedback system. |
