摘要 |
The toner supply roller 20 is so constructed that the outer diameter L of the toner supply roller 20 is set in a range of 10-13 mm, the outer diameter M of the roller shaft 20B is set in a range of 5-6 mm, and a difference between the distance between the rotating center E1 of the toner supply roller 20 and the rotating center E2 of the developing roller 19 and the sum of the radius R1 of the toner supply roller 20 and the radius R2 of the developing roller 19, i.e., the compression amount is set in a range of 0.5-0.8 mm so that there is a good balance between the rigidity of the roller shaft 20B and the rigidity of the roller member 20C. Accordingly, this makes it possible to use the toner supply roller 20 having a small roller diameter L and to supply just sufficiently toner to the developing roller 19. As a result, a resultant image excellent in image quality can be formed for a long period.
|