Abstract: An image forming apparatus includes a photosensitive member including a photosensitive layer and a protective layer provided outside the photosensitive layer; a charging member configured to electrically charge the photosensitive member; an exposure device configured to expose, to light, the photosensitive member charged by the charging member; a detecting member configured to detect a surface potential of the photosensitive member; and an output portion configured to output information on a lifetime of the photosensitive member. The output portion outputs the information on the basis of an exposure amount with which the photosensitive member charged is exposed to light and a detection result of the surface potentials of the photosensitive member by the detecting member before and after the photosensitive member is exposed to the light with the exposure amount.

Abstract: An image forming apparatus includes a photosensitive member, a corona charger including a discharging electrode and a grid electrode having a surface layer containing a carbon atom as a main component and configured to electrically charge the photosensitive member under application of a voltage to the discharging electrode and the grid electrode, and an output portion configured to output information on a lifetime of the grid electrode. The output portion outputs the information on the basis of an index value of an amount of use of the grid electrode correlating with a product of a value of a grid current flowing through the grid electrode and a time of flowing of the grid current through the grid electrode.

Abstract: An image forming apparatus includes a movable photosensitive member, first and second corona chargers, an adjusting mechanism, a developing device, a detecting member configured to detect a surface potential of the photosensitive member at a plurality of positions with respect to the widthwise direction of the photosensitive member, an input portion, and a display portion. In accordance with input of an instruction to the input portion, the detecting portion detects at least two surface potentials of three surface potentials including the surface potential of the photosensitive member after being charged by the first and second corona chargers, the surface potential of the photosensitive member after being charged by the first corona charger, and the surface potential of the photosensitive member after being charged by the second corona charger. A detection result of the detecting member is displayed at the display portion.

Abstract: An image forming apparatus includes a rotatable photosensitive member (drum), a first corona charger, a second corona charger, an image forming portion, a voltage applying portion, a surface potential detecting portion, a controller. The controller determines a condition of voltages applied to the first and second corona chargers during image formation, by setting a first voltage condition for the first corona charger so that the surface potential of the drum is a second potential lower in absolute value than the first potential in a state in which the first corona charger operates, and the second corona charger does not operates, and then by setting a second voltage condition for the second corona charger so that the surface potential of the drum is the first potential in a state in which the first corona charger operates under the first voltage condition, and the second corona charger operates.

Abstract: An image forming apparatus includes a rotatable photosensitive member (drum), a first corona charger, a second corona charger, an image forming portion, a voltage applying portion, a surface potential detecting portion, a controller. The controller determines a condition of voltages applied to the first and second corona chargers during image formation, by setting a first voltage condition for the first corona charger so that the surface potential of the drum is a second potential lower in absolute value than the first potential in a state in which the first corona charger operates, and the second corona charger does not operates, and then by setting a second voltage condition for the second corona charger so that the surface potential of the drum is the first potential in a state in which the first corona charger operates under the first voltage condition, and the second corona charger operates.

Abstract: A changing voltage is applied to a first charging roller. A voltage obtained by superimposing an alternating voltage on a direct voltage is applied to a second charging roller disposed on the downstream side of the first charging roller in the rotation direction of a photosensitive member. During image formation, the changing voltage applied to the first charging roller is changed so that the magnitude relationship between the potential of the photosensitive member which has been charged by using the first charging roller and which has reached a position at which the photosensitive member is charged by using the second charging roller and the direct voltage applied to the second charging roller is alternately switched.

Abstract: There is provided an image forming apparatus which includes multiple charging rollers and which can suppress accumulation of deposits such as external additives onto a charging roller without reducing productivity of the image forming apparatus. A changing voltage is applied to a first charging roller. A voltage obtained by superimposing an alternating voltage on a direct voltage is applied to a second charging roller disposed on the downstream side of the first charging roller in the rotation direction of a photosensitive member. During image formation, the changing voltage applied to the first charging roller is changed so that the magnitude relationship between the potential of the photosensitive member which has been charged by using the first charging roller and which has reached a position at which the photosensitive member is charged by using the second charging roller and the direct voltage applied to the second charging roller is alternately switched.

Abstract: An image forming system including: an executing unit configured to execute a duplex image forming mode including: a first duplex image forming mode in which a recording material, which is conveyed from a first recording material containing portion and has one surface subjected to image formation by a first image forming apparatus, is conveyed by a conveying unit, and another surface of the recording material is subjected to image formation by a second image forming apparatus; and a second duplex image forming mode in which one surface and another surface of a recording material conveyed from a second recording material containing portion are sequentially subjected to image formation by the second image forming apparatus; and an input portion through which an operator inputs a setting for execution of the second duplex image forming mode. Thus, power consumption can be reduced.

Abstract: An image forming apparatus which includes a photosensitive member and an image forming station. The image forming station includes a charging device for charging the member, an exposure device for exposing the member to light, a developing device for developing an electrostatic latent image on the member, and a bias applying device for applying a developing bias. The image forming apparatus also includes, a transfer device for transferring a toner image to a sheet, a setting device for setting an AC voltage, an executing device for executing a test mode, a density detecting device for detecting the density of the test image, and an adjusting device for adjusting an image forming condition for the station. When the executing device executes the test mode, test images can formed at various AC voltages.

Abstract: An image forming apparatus includes an image bearing member; a charging member for electrically charging the image bearing member through electric discharge by applying, to the charging member, a DC voltage biased with an AC voltage; and voltage condition determination means for determining a voltage condition during image formation on the basis of each of the values of AC currents obtained by applying a plurality of DC voltages biased with the AC voltages to said charging member.

Abstract: An image forming apparatus which includes a photosensitive member and an image forming station. The image forming station includes a charging device for charging the member, an exposure device for exposing the member to light, a developing device for developing an electrostatic latent image on the member, and a bias applying device for applying a developing bias. The image forming apparatus also includes, a transfer device for transferring a toner image to a sheet, a setting device for setting an AC voltage, an executing device for executing a test mode, a density detecting device for detecting the density of the test image, and an adjusting device for adjusting an image forming condition for the station. When the executing device executes the test mode, test images can formed at various AC voltages.

Abstract: An image forming apparatus includes a rotatable image bearing member; a charging member for electrically charging the image bearing member; developing device means for developing an electrostatic latent image formed on said image bearing member into a toner image and for collecting toner from the image bearing member; transfer device means for transferring the toner image onto a transfer material; a brush member rotatable in a direction identical or opposite to a rotational direction of the image bearing member and disposed downstream from the transfer device means and upstream from the charging member in the rotational direction of the image bearing member, the brush member contacting transfer residual toner while being supplied with a DC voltage of an opposite polarity to a normal charge polarity of the toner; and a moving member for moving the toner in a rotational axis direction of the brush member while contacting the brush member.

Abstract: An electrostatic latent image transferring apparatus applies a transferring bias to a transfer member in a transferring portion, wherein a transferring bias value is determined on the basis of a first detection result detected when the surface of the image bearing member which has passed a portion opposed to the developer carrying member when the developing bias is not applied passes the transferring portion, and a second detection result detected when the surface of the image bearing member which has passed the portion opposed to the developer carrying member when the transferring bias is applied passes the transferring portion.

Abstract: A surface of a photosensitive drum is electrically charged by a charging roller disposed in contact with or close to the photosensitive drum. A relationship between a voltage and a current is measured by applying peak-to-peak voltages to the charging roller in a discharged area and an undischarged area during pre-rotation, image formation, and non-image formation such as interval between successive sheets, of the photosensitive drum. From the measured value, a slope of a DC discharge start voltage and a DC discharge characteristic is calculated, so that a peak-to-peak voltage and a DC voltage value are applied to the charging roller during image formation while being corrected each time.

Abstract: An image forming apparatus includes a rotatable image bearing member; a charging member for electrically charging the image bearing member; developing means for developing an electrostatic latent image formed on said image bearing member into a toner image and for collecting toner from the image bearing member; transfer means for transferring the toner image onto a transfer material; a brush member rotatable in a direction identical or opposite to a rotational direction of the image bearing member and disposed downstream from the transfer means and upstream from the charging member in the rotational direction of the image bearing member, the brush member contacting transfer residual toner while being supplied with a DC voltage of an opposite polarity to a normal charge polarity of the toner; and a moving member for moving the toner in a rotational axis direction of the brush member while contacting the brush member.

Abstract: An electrostatic latent image transferring apparatus applies a transferring bias to a transfer member in a transferring portion, wherein a transferring bias value is determined on the basis of a first detection result detected when the surface of the image bearing member which has passed a portion opposed to the developer carrying member when the developing bias is not applied passes the transferring portion, and a second detection result detected when the surface of the image bearing member which has passed the portion opposed to the developer carrying member when the transferring bias is applied passes the transferring portion.

Abstract: An electrostatic latent image transferring apparatus applies a transferring bias to a transfer member in a transferring portion, wherein a transferring bias value is determined on the basis of a first detection result detected when the surface of the image bearing member which has passed a portion opposed to the developer carrying member when the developing bias is not applied passes the transferring portion, and a second detection result detected when the surface of the image bearing member which has passed the portion opposed to the developer carrying member when the transferring bias is applied passes the transferring portion.

Abstract: An image forming apparatus includes a rotatable image bearing member; charging means for electrically charging the image bearing member; exposure means for exposing the image bearing member charged by the charging means to light at an exposure position to form an electrostatic latent image; pre-exposure potential detecting means for detecting a potential on the image bearing member before exposure to the light, the pre-exposure potential detecting means being disposed at a position downstream of the charging means and upstream of the exposure position with respect to a rotational direction of the image bearing member; and potential adjusting means for adjusting the potential on the image bearing member before the exposure on the basis of an output of the potential detecting means, the potential adjusting means being disposed downstream of the pre-exposure potential detecting means and upstream of the exposure position with respect to the rotational direction of the image bearing member.

Abstract: In an image forming apparatus having a transferring apparatus for developing an electrostatic latent image on an image bearing member by applying a developing bias to a developer carrying member carrying a developer thereon, and electrostatically transferring the developer image on the image bearing member to a transfer medium by a transfer member to which a transferring bias is applied in a transferring portion, wherein a transferring bias value during a transferring operation is determined on the basis of a detection result when an operation of detecting a voltage-current characteristic regarding the transfer member has been performed during a non-transferring operation, the transferring bias value is determined on the basis of a first detection result detected when the surface of the image bearing member which has passed a portion opposed to the developer carrying member when the developing bias is not applied passes the transferring portion, and a second detection result detected when the surface of the i

Abstract: In case of a full-color image forming apparatus, Modulation Transfer Function (MTF) unevenness at an identical location in the longitudinal axis tends to be intensified. The image forming apparatus of the present invention includes a plurality of light emitting heads having rod lens arrays which focus imaging rays on photosensitive members and have different modulation transfer functions, thereby being capable of providing a high quality image at a low cost while preventing optical density unevenness from being produced in the image.