Abstract: A driving force transmission mechanism includes a first transmission member and a second transmission member that are arranged on an identical rotational center axis. The first transmission member includes one or more transmission claws engaged with the second transmission member. The transmission claw includes, at a position away from the rotational center axis, a fixing portion with respect to the first transmission member, and extends in a direction crossing a direction directed from the fixing portion to the rotational center axis. The second transmission member includes one or more stoppers engaged with a tip end of the transmission claw and one or more holding portions engaged with a side of the transmission claw, which faces the rotational center axis.

Abstract: A sliding bearing is made of a resin and includes a tubular portion that includes an outer peripheral surface including a D-cut surface. A flange portion, which protrudes from the D-cut surface, is formed at one end portion of the tubular portion. An engagement portion is formed at the other end portion of the tubular portion. A protruding portion is formed on the outer peripheral surface of the tubular portion at a circumferential position that is outside a region in which the D-cut surface is formed and that is outside a region in which the engagement portion is formed.

Abstract: The image forming apparatus includes: a paper feed unit; a print unit; a registration roller; a sheet leading end sensor provided downstream, in a transport direction of the recording paper, of the registration roller; a time measuring unit for measuring a time from a start point of transportation of the recording paper by the registration roller to a point of detection of the leading end of the recording paper by the sheet leading end sensor; a memory unit for storing a reference image forming time and a reference time; a print control unit; and an arithmetic unit for obtaining a difference between the reference time and the time detected by the time measuring unit. The print control unit adjusts the length of the image forming period in accordance with the adjusted image forming time determined based on the difference obtained by the arithmetic unit and the reference image forming time.

Abstract: A driving force transmission mechanism includes a first transmission member and a second transmission member that are arranged on an identical rotational center axis. The first transmission member includes one or more transmission claws engaged with the second transmission member. The transmission claw includes, at a position away from the rotational center axis, a fixing portion with respect to the first transmission member, and extends in a direction crossing a direction directed from the fixing portion to the rotational center axis. The second transmission member includes one or more stoppers engaged with a tip end of the transmission claw and one or more holding portions engaged with a side of the transmission claw, which faces the rotational center axis.

Abstract: A sliding bearing is made of a resin and includes a tubular portion that includes an outer peripheral surface including a D-cut surface. A flange portion, which protrudes from the D-cut surface, is formed at one end portion of the tubular portion. An engagement portion is formed at the other end portion of the tubular portion. A protruding portion is formed on the outer peripheral surface of the tubular portion at a circumferential position that is outside a region in which the D-cut surface is formed and that is outside a region in which the engagement portion is formed.

Abstract: An image forming apparatus includes a coating portion configured to perform a coating process that forms a coating film on a recording sheet with an image formed thereon, a main transport path configured to transport the recording sheet with the image formed thereon and to have a branching portion formed thereon, and a sub transport path configured to be once branched from the main transport path at the branching portion and to be returned to the main transport path again. The coating portion is disposed on the sub transport path.

Abstract: A set of adjustment pattern images includes first adjustment pattern images and second adjustment pattern images to be formed on a first side and a second side of a recording sheet, respectively, by an image forming apparatus. The set of adjustment pattern images is employed to adjust an image forming position by the image forming apparatus such that an image forming position of the first adjustment pattern images is aligned with an image forming position of the second adjustment pattern images. The set of adjustment pattern images includes at least two first adjustment pattern images that are spaced from each other and at least two second adjustment pattern images that are spaced from each other, and the first adjustment pattern images on the first side and the second adjustment pattern images on the second side are arranged alternately with each other.

Abstract: An image forming apparatus includes a registration roller configured to adjust a starting time point of conveying a paper sheet; a printing unit configured to form a color image or a monochrome image on a photosensitive drum, and transfer the image to the paper sheet at a downstream side with respect to the registration roller in a conveyance direction to print; a line sensor configured to detect a conveyance position at an upstream side with respect to the printing unit in the conveyance direction; and a control unit configured to obtain a displacement amount with respect to a preset reference position based on the conveyance position, correct an image formation position according to the displacement amount to correct a printing position on the paper sheet, and change a correction method for the printing position according to whether any of the color image and the monochrome image is formed.

Abstract: An image forming apparatus that forms a first image in an image region of printing paper and forms a second image in a non-image region of the printing paper that is outside the image region includes an enlargement/reduction ratio specification unit that enables an enlargement/reduction ratio to be specified for the second image; and an image forming unit that forms the first image in the image region of the printing paper without enlarging/reducing the first image and forms the second image and the non-image region on the printing paper after enlarging/reducing the second image and the non-image region by the enlargement/reduction ratio specified through the enlargement/reduction ratio specification unit.

Abstract: Disclosed is an image forming apparatus that forms a first image in an image region of printing paper and forms a second image in a non-image region of the printing paper that is outside the image region, the image forming apparatus comprising: an enlargement/reduction ratio specification unit that enables an enlargement/reduction ratio to be specified for the second image; and an image forming unit that forms the first image in the image region of the printing paper without enlarging/reducing the first image and forms the second image and the non-image region on the printing paper after enlarging/reducing the second image and the non-image region by the enlargement/reduction ratio specified through the enlargement/reduction ratio specification unit.

Abstract: An image forming apparatus includes a registration roller configured to adjust a starting time point of conveying a paper sheet; a printing unit configured to form a color image or a monochrome image on a photosensitive drum, and transfer the image to the paper sheet at a downstream side with respect to the registration roller in a conveyance direction to print; a line sensor configured to detect a conveyance position at an upstream side with respect to the printing unit in the conveyance direction; and a control unit configured to obtain a displacement amount with respect to a preset reference position based on the conveyance position, correct an image formation position according to the displacement amount to correct a printing position on the paper sheet, and change a correction method for the printing position according to whether any of the color image and the monochrome image is formed.

Abstract: An image forming apparatus includes an image forming portion that forms an image on a recording sheet, a transport path that transports the recording sheet with the image formed thereon by the image forming portion, a coating portion that performs a coating process that forms a coating film on the recording sheet that is being transported on the transport path, and a reading portion that reads a calibration chart on the recording sheet that is being transported on the transport path. The coating portion is disposed on the upstream side in a recording sheet transport direction of the reading portion on the transport path, a calibration process is performed for an image formed by the image forming portion, and the calibration chart is formed on the recording sheet by the image forming portion in order to perform the calibration process.

Abstract: In a registration step, the temperature near a polygon mirror (83) is detected by a first temperature sensor (85), and the internal ambient temperature of an image forming apparatus (1) is detected by a second temperature sensor (86). Also, a registration adjustment value of each color is determined and stored in a memory (75). In a printing step, the registration adjustment value (A) of each color determined in the registration step is corrected based on a change in the temperature near the polygon mirror (83) and a change in the internal ambient temperature of the image forming apparatus (1). Furthermore, the write timing of an electrostatic latent image onto each photosensitive drum (13) by an optical scanning device (11) is controlled. Then, the position of the electrostatic latent image on each photosensitive drum (13) is shifted by an amount corresponding to the corrected registration adjustment value.

Abstract: An image forming apparatus provided with a resin frame made of a resin, an image forming unit and a fixing unit includes a duct for allowing air to flow between the image forming unit and the fixing unit. The resin frame includes a main frame to which the image forming unit is attached, and a fixing unit attachment frame that is separate from the main frame and to which the fixing unit is attached, and the fixing unit attachment frame has a duct portion that constitutes at least one part of the duct.

Abstract: In one embodiment, an image forming apparatus (100) is provided with a resin frame (300) made of resin and an image forming unit (200). The image forming apparatus further includes a first duct (410) that allows air to flow on one side of the image forming unit (200), a second duct (420) that allows air to flow on the other side, and a third duct (430) that allows air to flow between the first duct and the second duct. The resin frame (300) has a first duct portion (311) that constitutes at least a portion of the first duct (410), and a second duct portion (321) that constitutes at least a portion of the second duct (420).

Abstract: A set of adjustment pattern images includes first adjustment pattern images and second adjustment pattern images to be formed on a first side and a second side of a recording sheet, respectively, by an image forming apparatus. The set of adjustment pattern images is employed to adjust an image forming position by the image forming apparatus such that an image forming position of the first adjustment pattern images is aligned with an image forming position of the second adjustment pattern images. The set of adjustment pattern images includes at least two first adjustment pattern images that are spaced from each other and at least two second adjustment pattern images that are spaced from each other, and the first adjustment pattern images on the first side and the second adjustment pattern images on the second side are arranged alternately with each other.

Abstract: In one embodiment, an image forming apparatus (100) is provided with a resin frame (300) made of resin and an image forming unit (200). The image forming apparatus further includes a first duct (410) that allows air to flow on one side of the image forming unit (200), a second duct (420) that allows air to flow on the other side, and a third duct (430) that allows air to flow between the first duct and the second duct. The resin frame (300) has a first duct portion (311) that constitutes at least a portion of the first duct (410), and a second duct portion (321) that constitutes at least a portion of the second duct (420).

Abstract: An image forming apparatus of the present invention includes a resin frame composed of a resin and an image forming unit that is removably inserted in the resin frame. The resin frame includes a base having a supporting surface that supports the image forming unit, a guide portion that extends in the base in an insertion direction in which the image forming unit is inserted along the supporting surface and that guides the image forming unit in the insertion direction while limiting movement of the image forming unit in an orthogonal direction that is orthogonal to the insertion direction, and a side plate portion that is provided at a peripheral edge of the base so as to extend in a direction perpendicular to the supporting surface, the base, the guide portion, and the side plate portion being integrally molded from a resin.

Abstract: A color image forming apparatus including a test pattern formation portion that forms test patterns of a plurality of colors in an image formation area in which images of the plurality of colors are formed on an image carrier and in an image non-formation area outside the image formation area on the image carrier, a detection portion that detects a shift of each of the test patterns of the plurality of colors formed in the image formation area and a shift of each of the test patterns of the plurality of colors formed in the image non-formation area, a computing portion that obtains, for each color, an offset value indicating an offset between the shift of the test pattern in the image non-formation area and the shift of the test pattern in the image formation area, and a storage portion that stores the offset value for each color.

Abstract: An image forming apparatus including: an output image forming section for forming an image and a pattern on a supporting medium under a prescribed condition; an output section for transferring the formed image on a recording sheet; a correction section for performing reading of the formed pattern and correcting the condition based on a result of the reading; and a correction control section for controlling operations of the output image forming section, the output section, and the correction section, wherein the correction control section identifies whether or not an area where the image is to be formed and an area where the pattern is to be formed overlap each other, and when the areas are identified that they do not overlap each other, the correction control section controls the output image forming section to simultaneously form the image and the pattern in parallel on the supporting medium.