Abstract: An image forming apparatus includes an intermediate transfer member, a sensor, and two image forming units. Each of the image forming units includes an image carrier, an image writer, two development rollers, and a switcher. The image writer writes an electrostatic latent image on the image carrier. Each of the development rollers selectively driven by the switcher visualizes the electrostatic latent image to form toner images in four colors. The toner images are transferred and superimposed onto the intermediate transfer member to form a color toner image. The color toner image is transferred onto a transfer sheet. One or more marks are formed on the intermediate transfer member. The sensor detects one of the marks. The image writer starts writing in synchronism with a sync clock signal of the image writer output immediately after the sensor detects the mark or output after a predetermined time period elapses after the sensor detects the mark.

Abstract: An image forming apparatus capable of decreasing the image unevenness of a superimposed image at the time of forming starting (head) lines of the images in respective colors with different beams in order to decrease a shift of a superimposed image. Let a position, where an image in a first color is formed with a beam A as a leading beam, be (a). Let a starting position of formation of an image in a second color be (b), and one dot (line) of shift arises in the superimposed image. In order to decrease the shift of the superimposed image, image formation is performed with selecting a beam B as a beam which writes a head of the image (c). When image formation is performed for color shift reduction with changing a leading beam for each color image, tonality correction is performed to each beam for subsequent images so as to decrease image unevenness due to the difference between shapes and exposure power of respective beams.

Abstract: A two-station type color image forming apparatus of the present invention includes intermediate members configured to support only a developing device or the developing device and image forming means other than an image carrier. The intermediate members are selectively locked to or unlocked from the body of the image forming apparatus. Members constituting the image forming means each can be simply replaced alone in accordance with its life.

Abstract: In a belt apparatus used for image formation structured such that processing unit used for image formation are placed around a belt extended between at least two rollers and at least one of the processing unit acts on a roller so as to impart a rotational load thereto, it is possible to avoid a reduction in the image quality of a transfer image on the belt caused by the roller that supports the belt receiving variations in the load due to the movement towards or away from the belt of a cleaning blade. A drive source is connected to the roller to which directly receiving the load variation making this roller the drive roller for the belt.

Abstract: An optical box for positioning and fixing respective optical components is provided and functions as a housing thereof. A support stand for positioning and mounting the respective optical components, respectively, is formed separately from the optical box, and is loaded in the optical box.

Abstract: An image forming apparatus capable of decreasing the image unevenness of a superimposed image at the time of forming starting (head) lines of the images in respective colors with different beams in order to decrease a shift of a superimposed image. Let a position, where an image in a first color is formed with a beam A as a leading beam, be (a). Let a starting position of formation of an image in a second color be (b), and one dot (line) of shift arises in the superimposed image. In order to decrease the shift of the superimposed image, image formation is performed with selecting a beam B as a beam which writes a head of the image (c). When image formation is performed for color shift reduction with changing a leading beam for each color image, tonality correction is performed to each beam for subsequent images so as to decrease image unevenness due to the difference between shapes and exposure power of respective beams.

Abstract: In a belt apparatus used for image formation structured such that processing unit used for image formation are placed around a belt extended between at least two rollers and at least one of the processing unit acts on a roller so as to impart a rotational load thereto, it is possible to avoid a reduction in the image quality of a transfer image on the belt caused by the roller that supports the belt receiving variations in the load due to the movement towards or away from the belt of a cleaning blade. A drive source is connected to the roller to which directly receiving the load variation making this roller the drive roller for the belt.

Abstract: An image forming device is provides, which comprises a body to be scanned that moves in a sub-scanning direction; a writing means for scanning the body in a main scanning direction with a light beam according to image information to form a reference image on the body and repeating the scanning plural times to form plural images; and a second body on which the plural images are overlaid to form a color image. The writing means starts writing the reference image at a start time ty1 when a main scanning synchronizing signal is firstly generated by the writing means after a time tx1 when a predetermined time has lapsed from detection of an image forming start signal of the sub-scanning direction for the reference image. A start time for an image other than the reference image is changed depending on the start time of the reference image.

Abstract: An apparatus and method for recording an image using a transfer-type recording mechanism are such that a layer of an intermediate transfer element is removably formed on a surface of an intermediate transfer medium. The intermediate transfer element includes an ultraviolet stabilizer and a powder mixture. The intermediate transfer layer is capable of being dissolved and swelled by applying an ink liquid on the intermediate transfer medium and enables a viscosity of the ink liquid residing thereon to be increased. An image is produced on the intermediate transfer medium by supplying the ink liquid thereon. The image is then transferred to the recording medium, so that a high quality image is produced without any blurring, mixing or penetration of the ink liquid.

Abstract: An image forming apparatus capable of decreasing the image unevenness of a superimposed image at the time of forming starting (head) lines of the images in respective colors with different beams in order to decrease a shift of a superimposed image. Let a position, where an image in a first color is formed with a beam A as a leading beam, be (a). Let a starting position of formation of an image in a second color be (b), and one dot (line) of shift arises in the superimposed image. In order to decrease the shift of the superimposed image, image formation is performed with selecting a beam B as a beam which writes a head of the image (c). When image formation is performed for color shift reduction with changing a leading beam for each color image, tonality correction is performed to each beam for subsequent images so as to decrease image unevenness due to the difference between shapes and exposure power of respective beams.

Abstract: An image forming apparatus of the present invention includes two developing units each including two developing rollers facing a particular photoconductive drum and rotatable about respective axis parallel to the axis of the drum. Each developing unit is supported by a respective image forming unit and angularly movable about an axis substantially parallel to the axis of the drum. When each developing unit is angularly moved by a preselected angle, a gap for development is established between one of the developing rollers and the associated drum.

Abstract: An image forming apparatus of the present invention includes a plurality of components that form image forming means and should be mounted or dismounted in a preselected order. Following one of the components with respect to the preselected order cannot be dismounted from the apparatus until preceding one of the same has been dismounted. The components are mounted to the apparatus in the reverse order. The components unremovable from the apparatus and positioned above the removable components in a preselected dismounting direction are retractable.

Abstract: An apparatus and method for recording an image using a transfer-type recording mechanism are such that a layer of an intermediate transfer element is removably formed on a surface of an intermediate transfer medium. The intermediate transfer element includes an ultraviolet stabilizer and a powder mixture. The intermediate transfer layer is capable of being dissolved and swelled by applying an ink liquid on the intermediate transfer medium and enables a viscosity of the ink liquid residing thereon to be increased. An image is produced on the intermediate transfer medium by supplying the ink liquid thereon. The image is then transferred to the recording medium, so that a high quality image is produced without any blurring, mixing or penetration of the ink liquid.

Abstract: In a belt apparatus used for image formation structured such that processing unit used for image formation are placed around a belt extended between at least two rollers and at least one of the processing unit acts on a roller so as to impart a rotational load thereto, it is possible to avoid a reduction in the image quality of a transfer image on the belt caused by the roller that supports the belt receiving variations in the load due to the movement towards or away from the belt of a cleaning blade. A drive source is connected to the roller to which directly receiving the load variation making this roller the drive roller for the belt.

Abstract: A two-station type color image forming apparatus of the present invention includes intermediate members configured to support only a developing device or the developing device and image forming means other than an image carrier. The intermediate members are selectively locked to or unlocked from the body of the image forming apparatus. Members constituting the image forming means each can be simply replaced alone in accordance with its life.

Abstract: A two-station type color image forming apparatus of the present invention includes intermediate members configured to support only a developing device or the developing device and an image forming device other than an image carrier. The intermediate members are selectively locked to or unlocked from the body of the image forming apparatus. Members constituting the image forming device each can be simply replaced alone at the end of their individual useful life.

Abstract: An image forming apparatus capable of obviating several difficulties such as the shear of superposed multiple color images in the vertical scanning direction, prolonged image forming periods resulted from rotating an intermediate transfer member as many times as image superposition, and undue complication of light beam scanning means caused by incorporating plural light deflecting means for exclusive use for each visible image forming units. These improved capabilities are embodied in a multiple color printer, for example.

Abstract: In a belt apparatus used for image formation structured such that processing unit used for image formation are placed around a belt extended between at least two rollers and at least one of the processing unit acts on a roller so as to impart a rotational load thereto, it is possible to avoid a reduction in the image quality of a transfer image on the belt caused by the roller that supports the belt receiving variations in the load due to the movement towards or away from the belt of a cleaning blade. A drive source is connected to the roller to which directly receiving the load variation making this roller the drive roller for the belt.

Abstract: An image forming apparatus of the present invention includes two developing units each including two developing rollers facing a particular photoconductive drum and rotatable about respective axis parallel to the axis of the drum. Each developing unit is supported by a respective image forming unit and angularly movable about an axis substantially parallel to the axis of the drum. When each developing unit is angularly moved by a preselected angle, a gap for development is established between one of the developing rollers and the associated drum.

Abstract: An image formation apparatus has photo conductor drums, and upstream developing rollers and downstream developing rollers that are brought into contact with respective photo conductor drums based on a changeover. The developing rollers develop latent images into visual images. A time required to change over a developing unit from one developing unit to the other developing unit is set as follows. A changeover time T2 from the downstream developing rollers to the upstream developing rollers respectively is set shorter than a changeover time T1 from the upstream developing rollers to the downstream developing rollers.