Abstract: An image forming apparatus includes a rotatable image bearing member; a first charging member for electrically charging the image bearing member; a second charging member, provided downstream of the first charging member with respect to a rotational direction of the image bearing member, for electrically charging the image bearing member; an applying device for applying a voltage to the first charging member and the second charging member; a detecting device for a DC current passing through the second charging member; and a controller for controlling, when an AC voltage and a DC voltage are applied to the second charging member while a DC voltage is applied to the first charging member, the DC voltage applied to the second charging member so that an absolute value of the DC current detected by the detecting device is within a predetermined range.

Abstract: An image forming apparatus includes a photosensitive member configured to form a toner image thereon, a corona charger located opposite the photosensitive member and including a discharging wire and a grid electrode, a bias applying unit configured to apply a bias to the corona charger, a cleaning unit configured to perform cleaning processing by sliding in a longitudinal direction of the grid electrode to rub an inner surface of the grid electrode, and an execution unit configured to execute a cleaning mode for performing the cleaning processing by the cleaning unit while applying a bias of a polarity equal to a normal charging polarity of toner to the grid electrode by the bias applying unit.

Abstract: A corona charger includes a charging wire and a plate grid. The plate grid comprises a stainless steel base and a surface layer formed of tetrahedral amorphous carbon on the base.

Abstract: An image forming apparatus includes image bearing member having a movable surface; charging means for charging the surface of the image bearing member; image exposure means for exposing the surface of the image bearing member charged by the charging means to light in accordance with image information, thus forming an electrostatic image; developing means for developing the electrostatic image formed on the image bearing member into a developed image; surface potential detecting means for detecting a potential of the surface of the image bearing member; discharging means for discharging the surface of the image bearing member; changing means for changing an image forming condition, wherein an area of the image bearing member passes the discharging means under different operating conditions of the discharging means, and the area is charged by the charging means, the changing means changes the image forming condition on the basis of a result of detection, by the surface potential detecting means, of surface pote

Abstract: An image forming apparatus includes a photosensitive member configured to form a toner image thereon, a corona charger located opposite the photosensitive member and including a discharging wire and a grid electrode, a bias applying unit configured to apply a bias to the corona charger, a cleaning unit configured to perform cleaning processing by sliding in a longitudinal direction of the grid electrode to rub an inner surface of the grid electrode, and an execution unit configured to execute a cleaning mode for performing the cleaning processing by the cleaning unit while applying a bias of a polarity equal to a normal charging polarity of toner to the grid electrode by the bias applying unit.

Abstract: An image forming apparatus including an image bearing member, a charging unit for charging the image bearing member, and an image exposure unit including a light emitting portion for emitting light to form an electrostatic image. The image forming apparatus also includes a developing unit including a toner carrying member and a bias controlling unit for applying a bias voltage to the toner carrying member, the developing unit being effective to develop the electrostatic image with toner by a potential difference between the toner carrying member and the electrostatic image, a potential difference determining unit, and a storing unit for storing a light amount control value, corresponding to the potential difference, set on a basis of a light emission amount information inherent to the light emitting portion. The image exposure unit reads the light amount control value and controls the light amount based on the light amount control value.

Abstract: An image forming apparatus includes an image bearing member having a photosensitive layer; toner image forming means for forming a detection toner image not to be formed on a recording material on the image bearing member; detecting means for optically detecting the detection toner image; control means for controlling a toner image forming condition of the toner image forming means on the basis of a result of detection of the detecting means; a transfer member for electrostatically transferring a toner image from the image bearing member onto a transfer material at a transfer region; constant voltage control means for providing a constant voltage applied to the transfer member; and voltage applying means for applying to the transfer member, when the detection toner image passes the transfer region, a predetermined voltage, controlled by the voltage control means, which has the same polarity as a charge polarity of toner.

Abstract: A corona charger includes a charging wire and a plate grid. The plate grid comprises a stainless steel base and a surface layer formed of tetrahedral amorphous carbon on the base.

Abstract: An image forming apparatus includes an image bearing member; charging means for charging a surface of the image bearing member; image exposure means for exposing the surface of the image bearing member charged by the charging means to light to form an electrostatic image on the surface of the image bearing member; switching means for switching a light emission level of the image exposure means in accordance with the set point of a light emission amount setting the light emission level of the image exposure means; storing means for storing light emission amount set points set corresponding to different target light emission levels of the image exposure means; light emission amount control means for controlling the light emission level of the image exposure means on the basis of information stored in the storing means; an input portion for inputting information relating to an actual light emission level of the image exposure means corresponding to a predetermined light emission amount set point; and correcting

Abstract: An image forming apparatus includes image bearing member having a movable surface; charging means for charging the surface of the image bearing member; image exposure means for exposing the surface of the image bearing member charged by the charging means to light in accordance with image information, thus forming an electrostatic image; developing means for developing the electrostatic image formed on the image bearing member into a developed image; surface potential detecting means for detecting a potential of the surface of the image bearing member; discharging means for discharging the surface of the image bearing member; changing means for changing an image forming condition, wherein an area of the image bearing member passes the discharging means under different operating conditions of the discharging means, and the area is charged by the charging means, the changing means changes the image forming condition on the basis of a result of detection, by the surface potential detecting means, of surface pote

Abstract: An image forming apparatus including image forming means for forming a toner image, which includes an image bearing member, a charger for charging the image bearing member, an exposure device for exposing the image bearing member to form an electrostatic image, and a developing device for developing the electrostatic image; a transfer member for electrostatically transferring a toner image from the image bearing member onto a recording material at a transfer region; detecting means for optically detecting a detection toner image formed on the image bearing member; control means for controlling a toner image forming condition of the toner image forming means on the basis of a result of detection of the detecting means; voltage applying means for applying to when the detection toner image passes the transfer region, a voltage having the same polarity as a charge polarity of the toner image, wherein potential difference between the voltage and a potential of a region of the image bearing member charged by the ch