| 摘要 |
<p>PROBLEM TO BE SOLVED: To securely prevent toner from being transferred, in the form of fog, to a photoreceptive drum in the direction of the length of a developing sleeve during development, and image density from becoming irregular due to an uneven amount of electrified charge of toner, and to perform the steady, satisfactory formation of a thin toner-layer on the developing sleeve. SOLUTION: In an opening opposite the photoreceptor drum 1 the developing sleeve 5 is provided sidewise, and its both ends are provided with end seal members 19. Toner electrification roller 20 are disposed at both ends of the developing sleeve 5 on the upstream side of a developing part. On the upstream side of it and in counter direction an elastic blade 7 is disposed, and on the further upstream side of it an elastic roller 6 is disposed. By using the toner electrification rollers 20, a bias whose voltage is higher than that used at the start of discharging and whose polarity is the same as that of the toner is applied to the nonmagnetic toner on the developing sleeve from a power source 18 shared with the developing sleeve 5.</p> |
