| 摘要 |
An image forming apparatus includes an intermediary transfer member, a first image forming portion including a first photosensitive member, a first charging member, a first developing device, a first transfer portion, and a first pre-exposure device, a second image forming portion including a second photosensitive member, a second charging member, a second developing device, a second transfer portion, and a second pre-exposure device, a current detecting portion, and an adjusting portion for adjusting an exposure amount of the first photosensitive member by the first pre-exposure device on the basis of a detection result of the detecting portion in a region on the first photosensitive member having contacted a toner band formed in a maximum amount per unit area on the intermediary transfer member by the second image forming portion in a state in which a transfer current is supplied. |
| 主权项 |
1. An image forming apparatus comprising:
a rotatable intermediary transfer member for carrying a toner image to be transferred onto a recording material; a first image forming portion including a rotatable first photosensitive member, a first charging member for electrostatically charging said first photosensitive member, a first developing device for developing an electrostatic latent image formed on a charged surface by said first charging member, a first transfer portion for transferring a toner image onto said intermediary transfer member, and a first pre-exposure device for exposing to light said first photosensitive member at a position downstream of said first transfer portion and upstream of said first charging member with respect to a rotational direction of said first photosensitive member; a second image forming portion including a rotatable second photosensitive member, a second charging member for electrostatically charging said second photosensitive member, a second developing device for developing an electrostatic latent image formed on a charged surface by said second charging member, a second transfer portion for transferring a toner image onto said intermediary transfer member, and a second pre-exposure device for exposing to light said second photosensitive member at a position downstream of said second transfer portion and upstream of said second charging member with respect to a rotational direction of said second photosensitive member, wherein said second image forming portion is positioned upstream of said first image forming portion with respect to a movement direction of said intermediary transfer member, a detecting portion for detecting a current flowing through said first charging member when a predetermined voltage is applied to said first charging member; and an adjusting portion for adjusting an exposure amount of said first photosensitive member by said first pre-exposure device on the basis of a detection result of said detecting portion in a region on said first photosensitive member having contacted a toner band formed in a maximum amount per unit area on said intermediary transfer member by said second image forming portion in a state in which a transfer current is supplied. |
