Fuji Xerox Co., Ltd.

Michio Taniwaki

Minoru Ohshima

Takao Furuya

Fumihiko Ogasawara

Yoshinari Iwaki

Toshio Hisamura

Osamu Yasui

Ken Tsuchiya

Michihiro Inoue

Kenichi Ito

A print head includes: a mounting board; a light source portion that includes a plurality of light emitting elements provided on one surface of the mounting board; a drive member that is provided on other surface of the mounting board so as to generate a lighting signal and drive the light source portion; and a first temperature detector that is provided on the mounting board, and at least one second temperature detector that is provided at a farther position on the mounting board from the drive member than the first temperature detector; and the drive member includes: a light emitting unit that generates the lighting signal based on a temperature detected by the first temperature detector and a temperature detected by the second temperature detector; and an optical unit that forms an image of light emitted from the light emitting unit.

Print head and image forming apparatus

A rotation amount detecting device for a rotation body includes: a first rotation body having a first surface; a second rotation body having a second surface formed of a material different from that of the first surface and contacting the first surface, and rotating with rotation of the first rotation body; a first support member rotatably supporting the first rotation body at a first position and supporting thereof to be swingable around a first axis at a position different from the first position; a second support member rotatably supporting the second rotation body at a second position and supporting thereof to be swingable around a second axis provided at a position different from the second position, the second axis being the first axis or an axis in the first support member other than the first axis; and a detector that detects a rotation amount of the second rotation body.

Rotation amount detecting device for rotation body, length measuring device and image forming apparatus

A sheet measuring apparatus includes a first rotating member including a first peripheral surface portion that contacts a transported sheet; a second rotating member including a second peripheral surface portion that contacts the first peripheral surface portion; a first rotation amount detecting unit that detects a first rotation amount of the first rotating member; a second rotation amount detecting unit that detects a second rotation amount of the second rotating member; a sheet calculation unit that obtains a first rotating member correction value for correcting an error that is superposed on the second rotation amount due to a radius distribution of the first rotating member and that performs calculation related to the transported sheet; a radius distribution calculating unit that calculates a new radius distribution of the first rotating member; and an updating unit that updates the first rotating member correction value to a new first rotating member correction value.

Sheet measuring apparatus and image forming apparatus

An abnormality detecting device for a rotation body includes: a rotation body rotating while coming in contact with a sheet transported at a predetermined speed; an output unit outputting pulses of a number in proportion to a rotation amount of the rotation body; an acquisition unit acquiring periodic information associating a position of the rotation body during a single rotation and a period of each of the pulses corresponding to the position with each other, the periodic information being acquired based on the plural pulses outputted from the output unit along with the rotation of the rotation body at the predetermined speed; a memory storing the periodic information as reference periodic information; and an abnormality detector detecting an abnormality occurred in at least one of the rotation body and the output unit based on the reference periodic information and new periodic information acquired after the reference periodic information is acquired.

Abnormality detecting device for rotation body and image forming apparatus

An exposure device includes a plurality of light-emitting elements, a lighting driver, a first storage, a reader, a shading correction unit and a second storage. The lighting driver drives and lights up the light-emitting elements based on image data. The first storage stores light amount unevenness correction values of the respective light-emitting elements. The reader reads the light amount unevenness correction values stored in the first storage. The shading correction unit executes shading correction for the light amount unevenness correction values read by the reader. The second storage stores correction values obtained by having the shading correction unit to execute the shading correction for the light amount unevenness correction values. The lighting driver controls light power of the respective light-emitting elements based on the correction values stored in the second storage.

Exposure device, image forming apparatus, exposure control method and computer-readable medium

A sheet measuring apparatus includes a first rotating member that includes a first peripheral surface portion that contacts a transported sheet; a second rotating member that includes a second peripheral surface portion made of a material different from that of the first peripheral surface portion, the second peripheral surface contacting the first peripheral surface portion and not contacting the sheet; a first rotation amount detecting unit that detects a first rotation amount that is a rotation amount of the first rotating member; a second rotation amount detecting unit that detects a second rotation amount that is a rotation amount of the second rotating member, the second rotation amount being used for a calculation related to the transported sheet; and a fault detecting unit that detects a fault that has occurred in the first rotating member on the basis of the first rotation amount and the second rotation amount.

An exposure device includes plural light emitting elements that light in turn for exposure, plural driving elements that drive each of the light emitting elements and a time changing member that changes one time period of a switching signal to switch light emitting elements driven by the driving elements among the plurality of light emitting elements in turn from a reference time, depending on an image forming speed, wherein the time changing member changes the one time period from the reference time for some of the light emitting elements during one main scan, and maintains the one time period as the reference time for the remaining light emitting elements.

Exposure device, image forming apparatus and computer readable medium storing program for exposure control

Magnification data for designating a recording magnification of an overall image along a horizontal scanning direction, magnification balance data for designating the balance in the recording magnification of left and right partial image regions, and write position data for designating the timing of starting the recording of an image are inputted on the basis of results of measurement of the positions of registration marks formed at the center and both ends of an image recording range. A phase selection circuit and a LSYNC generating circuit adjust the timing of starting the recording of an image on the basis of the write position data. A detecting circuit detects an average frequency of a pixel clock and a frequency difference of partial image regions during one scanning by a laser beam, and an average-frequency control circuit and a left-right frequency difference control circuit effect control on the basis of the detected frequencies such that during one scanning by the laser beam the pixel clock frequency (oscillation frequency of VCO) changes with a scope of change corresponding to the magnification balance data by using as a reference a frequency corresponding to the magnification data.

Growing community of inventors

Ebina, Japan

Michio Taniwaki