| 摘要 |
PURPOSE:To uniformly form a toner layer on a hard developing roller and to uniformize the charging amount of the toner by maintaining the contact pressure between a blade and the hard developing roller within a specified range. CONSTITUTION:The device is provided with the hard developing roller (developing roller) 24 as the first toner transporting means for carrying the one-component toner, and the blade 26 as the toner amount regulating means held in contact with the developing roller 24 for forming the toner on the developing roller 24 into a thin layer and triboelectrifying it. Then, the device is provided with the developing unit equipped with the second toner transporting means, held in contact with the developing roller 24 and the image carrier carrying the electrostatic latent image, receiving the toner from the developing roller 24, and making the toner stick to the electrostatic latent image on the image carrier. The contact pressure between the blade 26 and the developing roller 24 is maintained in the range between 20gf and 360gf. If the contact pressure becomes <=20gf, unevenness of the toner amount and the toner distribution per unit area on the developing roller 24 are increased, and if the contact pressure becomes >=360gf, the extreme unevenness in the thickness of the toner layer is caused, which is not preferable. |
