Abstract: A management apparatus that enhances efficiency of maintenance work of a plurality of image forming apparatuses. An apparatus management server is connected to a plurality of image forming apparatuses via a network. Each image forming apparatus includes a storage unit for storing information indicative of wear levels of members for outputting a color image, on a color-by-color basis. The management service acquires the information from each image forming apparatus, and selects an image forming apparatus for outputting an image based on the acquired information such that differences between the wear levels of the members become smaller between the image forming apparatuses.

Abstract: An image forming apparatus includes a member (drum), a charging device, an exposure device, a developing device, a transfer device, a cleaning blade, a selecting device for selecting an execution mode from an image forming mode and a recovery mode, and a controller for controlling a peak-to-peak voltage applied to the charging device in the operation in the recovery mode. When the recovery mode is selected, the controller effects control so that a band-like toner image is formed on the drum and is supplied to the cleaning blade and so that a peak-to-peak voltage of the AC voltage larger than that of the AC voltage applied to the charging device in the operation in the image forming mode is applied to the charging device in a predetermined period after a leading end of the band-like toner image subjected to removal by the cleaning blade passes through the charging device.

Abstract: An image forming apparatus includes a photosensitive member; a charging device for electrically charging the photosensitive member; an exposure device for exposing to light the photosensitive member electrically charged by the charging device to form an electrostatic image; a developing device for developing the electrostatic image with toner to form a first patch and a second patch; a detecting device for detecting a density of the first and second patches formed by the developing device; and a control device for controlling an image forming condition on the basis of a difference in density between the first patch formed on the photosensitive member at a portion where a surface potential of the photosensitive member is zero volts and the second patch formed at a portion electrically charged by applying a predetermined charging bias to the charging device.

Abstract: An image forming apparatus includes a member (drum), a charging device, an exposure device, a developing device, a transfer device, a cleaning blade, a selecting device for selecting an execution mode from an image forming mode and a recovery mode, and a controller for controlling a peak-to-peak voltage applied to the charging device in the operation in the recovery mode. When the recovery mode is selected, the controller effects control so that a band-like toner image is formed on the drum and is supplied to the cleaning blade and so that a peak-to-peak voltage of the AC voltage larger than that of the AC voltage applied to the charging device in the operation in the image forming mode is applied to the charging device in a predetermined period after a leading end of the band-like toner image subjected to removal by the cleaning blade passes through the charging device.

Abstract: An image forming apparatus includes a photosensitive member; a charging device for electrically charging the photosensitive member; an exposure device for exposing to light the photosensitive member electrically charged by the charging device to form an electrostatic image; a developing device for developing the electrostatic image with toner to form a first patch and a second patch; a detecting device for detecting a density of the first and second patches formed by the developing device; and a control device for controlling an image forming condition on the basis of a difference in density between the first patch formed on the photosensitive member at a portion where a surface potential of the photosensitive member is zero volts and the second patch formed at a portion electrically charged by applying a predetermined charging bias to the charging device.

Abstract: An image forming apparatus includes a photosensitive member; a charging device for electrically charging the photosensitive member; an exposure device for exposing to light the photosensitive member electrically charged by the charging device to form an electrostatic image; a developing device for developing the electrostatic image with toner to form a first patch and a second patch; a detecting device for detecting a density of the first and second patches formed by the developing device; and a control device for controlling an image forming condition on the basis of a difference in density between the first patch formed on the photosensitive member at a portion where a surface potential of the photosensitive member is zero volts and the second patch formed at a portion electrically charged by applying a predetermined charging bias to the charging device.

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; a charging device for electrically charging the photosensitive member; an exposure device for exposing to light the photosensitive member electrically charged by the charging device to form an electrostatic image; a developing device for developing the electrostatic image with toner to form a first patch and a second patch; a detecting device for detecting a density of the first and second patches formed by the developing device; and a control device for controlling an image forming condition on the basis of a difference in density between the first patch formed on the photosensitive member at a portion where a surface potential of the photosensitive member is zero volts and the second patch formed at a portion electrically charged by applying a predetermined charging bias to the charging device.

Abstract: In an early-middle stage of a photosensitive drum life cycle, an image forming apparatus uses only a second semiconductor laser having an oscillation wavelength 660 nm to perform writing of an electrostatic latent image on a photosensitive drum surface. In a middle-late stage of the photosensitive drum life cycle, the image forming apparatus starts using a first semiconductor laser having an oscillation wavelength of 440 nm in addition to the second semiconductor laser to perform writing of an electrostatic latent image on the photosensitive drum surface with a combined exposure spot formed at the same position. An exposure control unit gradually increases an output rate of the first semiconductor laser according to an increase in total output of the first and second semiconductor lasers.

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: In an early-middle stage of a photosensitive drum life cycle, an image forming apparatus uses only a second semiconductor laser having an oscillation wavelength 660 nm to perform writing of an electrostatic latent image on a photosensitive drum surface. In a middle-late stage of the photosensitive drum life cycle, the image forming apparatus starts using a first semiconductor laser having an oscillation wavelength of 440 nm in addition to the second semiconductor laser to perform writing of an electrostatic latent image on the photosensitive drum surface with a combined exposure spot formed at the same position. An exposure control unit gradually increases an output rate of the first semiconductor laser according to an increase in total output of the first and second semiconductor lasers.

Abstract: An image forming apparatus having a heating device that is configured to heat an image bearing member so that the detection of the surface potential of the image bearing member can be controlled with greater stability. The image forming apparatus utilizes a surface potential detector and a temperature detecting member placed in positions at a precise distance relative to an exposure portion of the image bearing member, such that the stability of the surface potential detection can be improved. When a surface potential of the image bearing member is detected, it is possible to reduce the amount of change in the potential caused by carriers generated immediately after an exposure operation, and to reduce variations in detection of the surface potential caused by variations in the temperature, so that the surface potential can be controlled with greater stability.

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 electrophotographic image forming apparatus in which a reduction in image density when continuous sheet supply endurance is effected under a low-humidity environment is prevented, and under a high-humidity environment, an image deletion is prevented. A photosensitive member has an undercoat layer, a charge generating layer and a charge transport layer, and the surface layer of the photosensitive member contains a compound of which at least one polymerization functional group has been polymerized or cross-linked and hardened. Also, the hardening of the surface layer is effected by electron irradiation. A temperature raising apparatus for heating the surface of the photosensitive member is controlled by a controlling device to thereby control the surface temperature of the photosensitive member. The controlling device has two or more stages of set temperatures, and uses a high set temperature when the photosensitive member is used under an environment in which the absolute amount of water vapor is great.

Abstract: An electrophotographic image forming apparatus in which a reduction in image density when continuous sheet supply endurance is effected under a low-humidity environment is prevented, and under a high-humidity environment, an image deletion is prevented. A photosensitive member has an undercoat layer, a charge generating layer and a charge transport layer, and the surface layer of the photosensitive member contains a compound of which at least one polymerization functional group has been polymerized or cross-linked and hardened. Also, the hardening of the surface layer is effected by electron irradiation. A temperature raising apparatus for heating the surface of the photosensitive member is controlled by a controlling device to thereby control the surface temperature of the photosensitive member. The controlling device has two or more stages of set temperatures, and uses a high set temperature when the photosensitive member is used under an environment in which the absolute amount of water vapor is great.

Abstract: A high-precision image control method that can be conducted frequently without time or labor. When a sheet-passing operation starts, maximum exposure is performed at present settings in a predetermined non-image forming area and potential is detected by a potential sensor. Detected potential is compared with VH at a first control to judge whether a difference of 10 V or more exists. For a difference of 10 V or more, the signal is made responsive to laser output for achieving VH set at the first control. When the last image forming for that job is performed, potential returns to the potential set at the first control, and control ends. When the last image forming is completed in a consecutive job during short-term variability of VH, VH is restored to its original potential before the next job, whereby settings obtained with the first control are restored.

Abstract: An electrophotographic image forming apparatus in which a reduction in image density when continuous sheet supply endurance is effected under a low-humidity environment is prevented, and under a high-humidity environment, an image deletion is prevented. A photosensitive member has an undercoat layer, a charge generating layer and a charge transport layer, and the surface layer of the photosensitive member contains a compound of which at least one polymerization functional group has been polymerized or cross-linked and hardened. Also, the hardening of the surface layer is effected by electron irradiation. A temperature raising apparatus for heating the surface of the photosensitive member is controlled by a controlling device to thereby control the surface temperature of the photosensitive member. The controlling device has two or more stages of set temperatures, and uses a high set temperature when the photosensitive member is used under an environment in which the absolute amount of water vapor is great.

Abstract: An image forming apparatus satisfying relations Xd>distance Xe between image exposure position and potential detecting member>2×?×PS×Vc/V?×Mc/M? and 0<distance Xt between image exposure position and temperature detecting member<50×?×PS×Vc/V?×Mc/M? (?: time constant (sec) in a hole mobility measurement by TF method; PS: process speed (mm/sec); Vc: latent image contrast (V) necessary for image formation; Mc: thickness (cm) of charge transport layer in a photosensitive member; V?: bias (V) applied to a specimen in a hole mobility measurement by TF method; M?: thickness (cm) of a charge transport layer of a specimen employed in a hole mobility measurement by TF method; and Xd: distance (mm) of an image exposure portion and a developing device in a position opposed to the photosensitive member.

Abstract: A high-precision image control method that can be conducted frequently without time or labor. When a sheet-passing operation starts, maximum exposure is performed at present settings in a predetermined non-image forming area and potential is detected by a potential sensor. Detected potential is compared with VH at a first control to judge whether a difference of 10 V or more exists. For a difference of 10 V or more, the signal is made responsive to laser output for achieving VH set at the first control. When the last image forming for that job is performed, potential returns to the potential set at the first control, and control ends. When the last image forming is completed in a consecutive job during short-term variability of VH, VH is restored to its original potential before the next job, whereby settings obtained with the first control are restored.