| 摘要 |
An image forming apparatus includes an image bearing member for bearing a toner image; a rotatable intermediary transfer member onto which the toner image is to be primary-transferred from the image bearing member; a contact member movable toward and away from the intermediary transfer member; a voltage applying unit for applying a voltage to the contact member; a current detecting circuit for detecting a current passing through the contact member to which the voltage is applied by the voltage applying unit; and a control portion for effecting control so that the contact member is contacted to or separated from the intermediary transfer member. The control portion is capable of executing an operation in a measuring mode in which a contact time required to bring the contact member into contact to the intermediary transfer member is calculated, based on a change in current detected by the current detecting circuit, when the contact member to which an initial voltage is applied by the voltage applying unit is contacted to the intermediary transfer member by being moved from a separated state so as to be contacted to the intermediary transfer member. The control portion brings, during image formation, the contact member into contact to a non-image region on the intermediary transfer member based on the contact time. |
