Abstract: In a printer 10 provided with image formation units 60a to 60d arranged in tandem so as to be in contact with an intermediate transfer belt 52 that is stretched taut between a driving roller 53 and driven rollers 56a to 56c, the intermediate transfer belt 52 moves at speed Vb, the circumference of a photoconductive drum 61 of each of the image formation units 60a to 60d moves at speed Vd, and Vb and Vd are so set as to be Vb>Vd. When the printer 10 is activated, after the intermediate transfer belt 52 starts to rotate, the photoconductive drums 61 start to rotate one after the next starting with the one disposed most downstream along the rotation direction of the intermediate transfer belt 52.

Abstract: Disclosed is an image forming apparatus, which comprises an intermediate transfer belt (15), and a plurality of image-forming units (11) to (14) disposed along the intermediate transfer belt (15) and adapted to form toner images of different colors and sequentially transfer the toner images onto the intermediate transfer belt (15) in a superimposed manner so as to form a color toner image. The intermediate transfer belt (15) is laid across a drive roller (16), a driven roller (17) and a tension roller (18), in a tensioned condition. A rotation speed of the tension roller (18) adapted to apply a tension to the intermediate transfer belt (15) is detected to obtain a linear speed of the intermediate transfer belt (15). In a process of color-misregistration correction, a write-start timing for each toner image of the colors is adjusted based on the linear speed of the intermediate transfer belt (15).

Abstract: Disclosed is an image forming apparatus, which comprises an intermediate transfer belt (15), and a plurality of image-forming units (11) to (14) disposed along the intermediate transfer belt (15) and adapted to form toner images of different colors and sequentially transfer the toner images onto the intermediate transfer belt (15) in a superimposed manner so as to form a color toner image. The intermediate transfer belt (15) is laid across a drive roller (16), a driven roller (17) and a tension roller (18), in a tensioned condition. A rotation speed of the tension roller (18) adapted to apply a tension to the intermediate transfer belt (15) is detected to obtain a linear speed of the intermediate transfer belt (15). In a process of color-misregistration correction, a write-start timing for each toner image of the colors is adjusted based on the linear speed of the intermediate transfer belt (15).

Abstract: An image forming apparatus includes an image forming section for forming a plurality of toner images on a plurality of image bearing members respectively by an electrographic system; an endless belt to which the plurality of toner images are to be superimposedly transferred from the plurality of image bearing members, the endless belt being arranged close to the image forming section; a driving roller which the endless belt is placed on and is adapted to drive the endless belt; a driven roller which the endless belt is placed on; a detector for detecting a surface condition of the endless belt; and a controller for controlling at least one of the surface speed of the image bearing member and the moving speed of the endless belt in accordance with an output from the detector.

Abstract: An intermediate transfer belt 24 includes an elastic layer 242 on a resin layer 241. The material of the secondary transfer roller 31 has a hardness of 65° which is higher than a hardness of 60° of the material of the drive roller 25a. As a result, when the secondary transfer roller 31 is pressed against the drive roller 25a via the transfer medium and the intermediate transfer belt 24, the elastic layer 242 formed on the intermediate transfer belt 24 is elastically deformed to decrease the stress concentration in the toner at the pressing position, which suppresses the defect of transferred toner which is generated as a result of the stress concentration in the toner at the pressing position.

Abstract: Image transfer method and apparatus in which scratches due to entrainment of particles on an image carrier for a toner image having maximum spectroreflectivity at a wavelength of 550 nm do not produce perceptible flaws in resulting images transferred to a recording medium, since images formed with toner of maximum spectroreflectivity at 550 nm on white recording medium are difficult for human eyes to discern. When cleaning residual toner from transfer belts, reverse bias voltage is applied to at least one transfer roller, the peripheral velocity of the photosensitive drum on which a yellow toner image having maximum spectroreflectivity at 550 nm is formed is allowed to differ from the transfer velocity of the transfer belt, and at least the photosensitive drum on which the yellow toner image of maximum spectroreflectivity at 550 nm is formed is detached from the transfer belt.

Abstract: Disclosed is an image forming apparatus, which comprises an intermediate transfer belt (15), and a plurality of image-forming units (11) to (14) disposed along the intermediate transfer belt (15) and adapted to form toner images of different colors and sequentially transfer the toner images onto the intermediate transfer belt (15) in a superimposed manner so as to form a color toner image. The intermediate transfer belt (15) is laid across a drive roller (16), a driven roller (17) and a tension roller (18), in a tensioned condition. A rotation speed of the tension roller (18) adapted to apply a tension to the intermediate transfer belt (15) is detected to obtain a linear speed of the intermediate transfer belt (15). In a process of color-misregistration correction, a write-start timing for each toner image of the colors is adjusted based on the linear speed of the intermediate transfer belt (15).

Abstract: The difference between the light reception output signals representing the amounts of regularly and irregularly reflected light as measured, with optical detecting means that can measure the amount of regularly and irregularly reflected light simultaneously, when no toner is adhered to a transfer belt is set as a reference value, a corrected output value is calculated by correcting, based on the reference value, the difference between the light reception output signals representing the amounts of regularly and irregularly reflected light as measured when a toner image is formed, and the amount of toner adhered to the transfer belt is calculated based on the corrected output value. With transfer belts of different colors, if their surface gloss is equal to or lower than a predetermined value, the relationship between the coverage ratio and the toner adhesion amount remains approximately identical.

Abstract: In a printer 10 provided with image formation units 60a to 60d arranged in tandem so as to be in contact with an intermediate transfer belt 52 that is stretched taut between a driving roller 53 and driven rollers 56a to 56c, the intermediate transfer belt 52 moves at speed Vb, the circumference of a photoconductive drum 61 of each of the image formation units 60a to 60d moves at speed Vd, and Vb and Vd are so set as to be Vb>Vd. When the printer 10 is activated, after the intermediate transfer belt 52 starts to rotate, the photoconductive drums 61 start to rotate one after the next starting with the one disposed most downstream along the rotation direction of the intermediate transfer belt 52.

Abstract: An image transfer method and apparatus are provided, with which, even if scratches are produced due to entrainment of foreign matter on the surface of the image carrying body on which a toner image of which the spectroreflectivity at wavelength of 550 nm is the highest is to be formed, the image transferred to a recording medium is not perceived to have a flaw, for the image formed with the toner of which the spectroreflectivity at wavelength of 550 nm is the highest is difficult for human eyes to discern when it is printed on a white recording medium.

Abstract: A driving mechanism for use in an image forming apparatus has a rotary shaft, a driving joint, a drum gear, a cleaning roller gear, and a transfer roller gear. The rotary shaft extends through a photosensitive member along an axis of rotation of the photosensitive member. The rotary shaft is rotatably supported at the opposite axial end parts thereof by bearings, respectively. The rotary shaft is un-rotatably jointed to the photosensitive member relative thereto at a lateral side part of a rear end part of the rotary shaft corresponding to the rear side of the image forming apparatus. The driving joint is jointed to the rear end part of the rotary shaft protruding from the photosensitive member at the rear side of the image forming apparatus to input a rotating force of a drum motor to the photosensitive drum. The drum gear is provided at the rear side of the photosensitive member. The cleaning roller gear and the transfer roller gear are in mesh with the drum gear.

Abstract: A driving mechanism for use in an image forming apparatus has a rotary shaft, a driving joint, a drum gear, a cleaning roller gear, and a transfer roller gear. The rotary shaft extends through a photosensitive member along an axis of rotation of the photosensitive member. The rotary shaft is rotatably supported at the opposite axial end parts thereof by bearings, respectively. The rotary shaft is un-rotatably jointed to the photosensitive member relative thereto at a lateral side part of a rear end part of the rotary shaft corresponding to the rear side of the image forming apparatus. The driving joint is jointed to the rear end part of the rotary shaft protruding from the photosensitive member at the rear side of the image forming apparatus to input a rotating force of a drum motor to the photosensitive drum. The drum gear is provided at the rear side of the photosensitive member. The cleaning roller gear and the transfer roller gear are in mesh with the drum gear.