Patent ID: 9606470
Date: 2017-03-28
CPC Classifications: G03G

Claim:
1. An image forming apparatus comprising: a rotatable photoconductor; a charging unit configured to charge the photoconductor at a charging position by applying a DC voltage; a charging power supply configured to apply the DC voltage to the charging unit; a current detection unit configured to detect a charging current flowing in the charging unit; a toner image forming unit configured to form a toner image on a surface of the photoconductor charged by the charging unit; a transfer unit configured to transfer the toner image formed on the photoconductor by the toner image forming unit by applying transfer voltage to member to be transferred in transfer position; a transfer power supply configured to apply the transfer voltage to the transfer unit; an irradiation unit provided with a light source outputting light corresponding to input, and a guide member guiding the light output from the light source to arrive at the surface of the photoconductor, and configured to irradiate the surface of the photoconductor with the light output from the light source at an irradiation position downstream of the transfer position and upstream of the charging position in a rotational direction of the photoconductor; a photoconductor unit including at least the photoconductor and guide member, wherein the photoconductor unit is detachably attached to the image forming apparatus in a state where the light source is mounted on the image forming apparatus, a control unit configured to control the input in the light source during image formation in which the toner image is formed by the toner image forming unit, wherein when an unused photoconductor unit is attached, the control unit executes the following mode in which the control unit detects a first current that flows in the charging unit by the current detection unit when the surface of the photoconductor, which passed through the transfer position with the transfer voltage being applied to the transfer unit after charged at the charging position and passed through the irradiation position without irradiation of light by the irradiation unit thereafter, is re-charged at the charging position, and the control unit detects a second current that flows in the charging unit by the current detection unit when the surface of the photoconductor passed through the transfer position with the transfer voltage being applied to the transfer unit after charged at the charging position and passed through the irradiation position with irradiation of light by the irradiation unit thereafter, is re-charged at the charging position, and the control unit controls the input with respect to the light source during the image formation based on the first current and the second current detected in the mode, wherein the control unit sets the input during the image formation in which the second current in the mode becomes a target value which is set based on the first current.