Patents by Inventor Yuji Matsuda

Yuji Matsuda has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7729024
    Abstract: A color-drift correcting method in an image forming apparatus includes a first and a second color-drift correcting. The first color-drift correcting includes correcting the color-drift amount in a sub scanning direction and a skew relative to the reference color image being based on each color-drift amount of at least three mark-patterns, each of which mark-pattern is formed each color image, so as to decide a corrected-image line as a virtual image line for each color, assumed when the color images are superposed onto a transfer media. A second color-drift correcting includes correcting the color-drift amount in the sub scanning direction so that the virtual image lines corresponding to each of the colors other than the reference color intersect with the virtual image line of the reference color at at least two points.
    Type: Grant
    Filed: October 4, 2006
    Date of Patent: June 1, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazuhiko Kobayashi, Joh Ebara, Yasuhisa Ehara, Noriaki Funamoto, Toshiyuki Uchida, Seiichi Handa, Yuji Matsuda
  • Patent number: 7711280
    Abstract: An image forming apparatus comprising a fixation device having a heating part for heating and fixing a toner image formed on a recording medium is provided, which comprises a rotational velocity detecting part for detecting a rotational velocity of a conveyance roller for conveying the recording medium and a control part for estimating a surface temperature of the recording medium based on the rotational velocity of the conveyance roller detected by the rotational velocity detecting part, for estimating a temperature change of the heating part at a time of fixation based on the estimated surface temperature, and for determining a heating control variable of the heating part based on the temperature change.
    Type: Grant
    Filed: October 20, 2006
    Date of Patent: May 4, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuji Matsuda, Manabu Kodama
  • Patent number: 7693468
    Abstract: An image forming apparatus includes a plurality of image carriers, an optical writing unit, a plurality of developing units, a transfer member, a transfer unit, an image sensor, and a control unit. In at least one embodiment, the image sensor is configured to sense a positional displacement detection pattern including visible images on the transfer member to detect a positional displacement between the visible images on each of the plurality of image carriers. The control unit is configured to execute a positional displacement correction control to calculate an amount of the positional displacement and determine respective target drive speeds of the plurality of drive sources. The control unit is also configured to control so that the positional displacement detection pattern is formed when the plurality of drive sources are driven at substantially identical speeds and the positional displacement detection pattern thus formed is sensed by the image sensor.
    Type: Grant
    Filed: April 27, 2007
    Date of Patent: April 6, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasuhisa Ehara, Kazuhiko Kobayashi, Joh Ebara, Kouji Amanai, Seiichi Handa, Yuji Matsuda, Toshiyuki Uchida, Noriaki Funamoto, Keisuke Sugiyama
  • Patent number: 7653332
    Abstract: An image forming apparatus includes: image detectors to detect conditions of images, respectively, formed on a transfer member; sensors to detect rotational displacements of latent image carriers, respectively; and a controller to perform at least phase adjustment control and image-to-image displacement control before performing image forming operations on image carriers, respectively. Image-to-image displacement control includes adjusting image forming timing on the image carriers based upon conditions of a detection image (including images transferred from the image carrier) detected by the image detectors, respectively. Speed-variation detection control includes detecting a condition of a speed-variation detection image (including an image transferred from each of image carriers) via the image detectors, and determining speed variation of the image carriers, respectively, per one revolution based upon outputs of the image detectors and the sensors.
    Type: Grant
    Filed: April 27, 2007
    Date of Patent: January 26, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasuhisa Ehara, Kazuhiko Kobayashi, Joh Ebara, Noriaki Funamoto, Seiichi Handa, Yuji Matsuda, Kouji Amanai, Toshiyuki Uchida, Keisuke Sugiyama
  • Publication number: 20090263158
    Abstract: In an image forming apparatus, during a rotation of an intermediate transfer belt performed after a contact-state-changing rotation in which the number of photoconductors contacting the intermediate transfer belt has changed, a control unit of a belt driving device controls the driving speed of a belt driving motor based on a period of the intermediate transfer belt determined in the rotation immediately before the contact-state-changing rotation instead of a period determined in the contact-state-changing rotation.
    Type: Application
    Filed: April 8, 2009
    Publication date: October 22, 2009
    Inventors: Takuya Murata, Kazuhiko Kobayashi, Yuji Matsuda, Yuichiro Ueda, Hiromichi Matsuda, Toshiyuki Andoh, Joh Ebara, Yohei Miura, Takuya Uehara
  • Publication number: 20090238613
    Abstract: A belt drive control device includes: first and second detection devices which detect the angular displacement or velocity of a driven rotary member and the angular displacement or velocity of a drive rotary member, respectively; an extraction device which extracts, from the difference between the detection results of the first and second detection devices, the amplitude and phase of a variation component due to belt thickness variation; a control device which controls the rotation of the drive rotary member in accordance with the extracted amplitude and phase; first and second holding devices which hold the extracted amplitude and phase and normal ranges of the amplitude and phase, respectively; and first and second feedback devices which feed back the amplitude and phase to the rotation control, and performs feedback by using a substitution value for the amplitude or phase if the amplitude or phase is out of the normal range, respectively.
    Type: Application
    Filed: March 18, 2009
    Publication date: September 24, 2009
    Inventors: Yuichiro UEDA, Kazuhiko Kobayashi, Takuya Uehara, Takuya Murata, Yuji Matsuda, Takahiro Kamekura, Toshiyuki Andoh, Hiromichi Matsuda, Hiroki Ohkubo
  • Patent number: 7587157
    Abstract: An image forming apparatus includes a latent image carrier having a moving surface on which a latent image is formed, a drive control mechanism to control a drive of the latent image carrier so as to match a rotation angular speed of the latent image carrier with a target rotation angular speed thereof, a surface moving member having a moving surface on which an adjustment pattern for use in controlling the drive of the latent image carrier is formed, an image forming mechanism to develop the latent image with toner and transfer a resultant toner image on the surface moving member so as to form the adjustment pattern along a surface moving direction thereof, a pattern sensor to detect the adjustment pattern, a correction mechanism to correct the target rotation angular speed of the latent image carrier based on an amplitude and a phase of a variable component in a pattern interval of the adjustment pattern detected with the pattern sensor.
    Type: Grant
    Filed: January 25, 2007
    Date of Patent: September 8, 2009
    Assignee: Ricoh Co., Ltd.
    Inventors: Hiromichi Matsuda, Hiroshi Koide, Joh Ebara, Toshiyuki Andoh, Yasuhisa Ehara, Kazuhiko Kobayashi, Yuji Matsuda
  • Publication number: 20090190972
    Abstract: A belt drive control unit controls a rotation of belt supported by first and second rollers. Each of rotations of the first and second rollers are detected as first and second results. A rotation of the first roller is controlled in connection with thickness fluctuation in the belt using the first and second results. The belt drive control unit includes a sampling data acquisition unit, a correction value generator, a correction value storage, and a correction value reading controller. The sampling data acquisition unit obtains sampling data by sampling a difference value between the first and second results. The correction value generator generates correction value data for the belt based on the sampling data. The correction value storage stores the correction value data. The correction value reading controller reads the correction value data based on a rotation number of the belt to control a rotation of the first roller.
    Type: Application
    Filed: January 29, 2009
    Publication date: July 30, 2009
    Inventors: Hiroki Ohkubo, Hiromichi Matsuda, Toshiyuki Andoh, Yuji Matsuda, Yuichiro Ueda, Kazuhiko Kobayashi, Takuya Uehara, Takuya Murata
  • Publication number: 20090169225
    Abstract: A driving control device for use in an image forming apparatus includes a control unit that analyzes any one of a speed variation pattern and a thickness variation pattern of an endless belt member of the image forming apparatus per at least one rotation of the endless belt member while endlessly moving the endless belt member by a driving rotating unit, and starts to execute, based on a result of analysis, a driving-speed-control-pattern updating process to update a driving speed control pattern of the driving rotating unit per at least one rotation of the endless belt member, after a power of an image forming apparatus is turned on and within a preparation period in which a predetermined preparation process is completed so that an image forming operation can be started based on an image formation command from an operator.
    Type: Application
    Filed: December 11, 2008
    Publication date: July 2, 2009
    Inventors: Takuya Murata, Kazuhiko Kobayashi, Takuya Uehara, Yuji Matsuda, Yuichiro Ueda, Hiromichi Matsuda, Toshiyuki Andoh, Joh Ebara, Yohei Miura
  • Publication number: 20090135285
    Abstract: A solid-state image pickup device relating to the present invention comprises a pixel area where multiple pixels used for photoelectric conversion of incident light are two-dimensionally arranged. Vertical signal input lines to which vertical transfer signals for transferring signal charges generated at the pixels vertically in the pixel area are applied are connected to the pixel area. Furthermore, horizontal signal input lines to which horizontal transfer signals for horizontally transferring the signal charges are applied are connected to a horizontal transfer part for horizontally transferring the signal charges transferred vertically in the pixel area. A signal separation part separates vertical and horizontal transfer signals from a pulse signal supplied via a complex signal input terminal and supplies the separated signals to the vertical signal input line and the horizontal signal input line, respectively.
    Type: Application
    Filed: November 12, 2008
    Publication date: May 28, 2009
    Inventor: Yuji MATSUDA
  • Publication number: 20090091959
    Abstract: In an image forming apparatus, a monitoring unit monitors whether a returning factor required to switch an operational state of the apparatus from a power-saving mode to an operating mode is generated, an antenna unit receives external electrical wave, a power generation unit generates electricity from the received electrical wave and supplies the electricity to the monitoring unit, and a controlling unit switches the operational state of the apparatus from the power-saving mode to the operating mode when the monitoring unit detects generation of a returning factor.
    Type: Application
    Filed: September 30, 2008
    Publication date: April 9, 2009
    Inventors: Hiroyuki Takahashi, Eiji Nemoto, Hiroki Ohkubo, Yuji Matsuda, Yusuke Ozaki
  • Publication number: 20090072781
    Abstract: A power supply device accumulates charges generated by a photovoltaic unit. The power supply device includes a first capacitor having a first capacitance, in which the charges generated by the photovoltaic unit are charged; a second capacitor having a second capacitance that is larger than the first capacitance; and a switching unit that switches between a first connection of connecting the photovoltaic unit to the first capacitor and a second connection of connecting the first capacitor to the second capacitor.
    Type: Application
    Filed: September 8, 2008
    Publication date: March 19, 2009
    Inventors: Hiroyuki TAKAHASHI, Yusuke Ozaki, Eiji Nemoto, Yuji Matsuda, Hiroki Ohkubo
  • Patent number: 7499667
    Abstract: An endless belt drive controlling apparatus includes an endless belt and its drive unit, a first detector that detects a belt mark, a second detector that detects a detected angular displacement error of an encoder generated due to a variation in a thickness of the endless belt, a first calculating unit that calculates a phase and a maximum amplitude of the endless belt at the belt mark based on the detected angular displacement error of the encoder thus obtained, and a second calculating unit that calculates a position of the endless belt at which the detected angular displacement error is a minimum from the phase stored in a nonvolatile memory. The drive unit controls the endless belt so that the portion thereof at which the detected angular displacement error is the minimum is stopped at one of the rollers at which a highest tension is applied to the endless belt when the driver issues a belt stop command.
    Type: Grant
    Filed: May 30, 2006
    Date of Patent: March 3, 2009
    Assignee: Ricoh Company, Ltd.
    Inventor: Yuji Matsuda
  • Publication number: 20080292351
    Abstract: A thermoelectric conversion element converts thermal energy of a user into electric power. A holding unit holds the electric power converted by the thermoelectric conversion element, and outputs the electric power. A switching unit switches between a first mode in which electric power is supplied to all units of an image forming apparatus and a second mode in which electric power is supplied to a part of units of the image forming apparatus. When the image forming apparatus is in the second mode, the switching unit switches from the second mode to the first mode upon receiving the electric power output from the holding unit.
    Type: Application
    Filed: May 23, 2008
    Publication date: November 27, 2008
    Inventors: Yuji MATSUDA, Hiroyuki Takahashi, Hiroki Ohkubo, Yusuke Ozaki, Eiji Nemoto
  • Patent number: 7454150
    Abstract: An image forming apparatus includes a belt stretched across rollers and a resist rotary member that feeds out a recording medium on the belt. A correlation between a velocity of the belt and the resist rotary member is obtained. A target velocity of the belt or the resist rotary member, at which a difference between the velocity when the recording medium is in contact with both the belt and the resist rotary member and the velocity when the recording medium is not in contact with at least either the belt or the resist rotary member is minimum, is determined based on the correlation.
    Type: Grant
    Filed: January 9, 2006
    Date of Patent: November 18, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiromichi Matsuda, Toshiyuki Andoh, Masato Yokoyama, Kazuhiko Kobayashi, Yuji Matsuda, Yohei Miura, Hiroshi Okamura, Nobuto Yokokawa, Ryoji Imai
  • Publication number: 20080259071
    Abstract: A display control unit performs a control of displaying first image information on a display unit. An electric-power supply unit converts thermal energy generated from a body temperature of a user into electric power upon the user contacting the electric-power supply unit, and supplies the electric power to the display control unit. A determination unit determines whether the user is in contact with the electric-power supply unit. When it is determined that the user is not in contact with the electric-power supply unit, the display control unit performs a control of rewriting the first image information displayed on the display unit with second image information.
    Type: Application
    Filed: April 21, 2008
    Publication date: October 23, 2008
    Inventors: Eiji NEMOTO, Hiroki OHKUBO, Yuji MATSUDA, Yusuke OZAKI, Hiroyuki TAKAHASHI
  • Publication number: 20080198425
    Abstract: In an image forming apparatus, an energy converting unit receives light from an optical source and converts the light into electric power, and an electrical storage unit stores therein the electric power. The energy converting unit is arranged in such a manner that a relative position of the energy converting unit to the optical source is always constant when a reading unit is reading an image.
    Type: Application
    Filed: February 15, 2008
    Publication date: August 21, 2008
    Inventors: Yusuke Ozaki, Eiji Nemoto, Hiroki Ohkubo, Yuji Matsuda, Hiroyuki Takahashi
  • Patent number: 7386262
    Abstract: A belt driving control apparatus, the belt driving control apparatus having an endless belt, a driving roller driving the endless belt, a driving motor driving the driving roller, at least one idler roller being dependent on the endless belt, and an encoder attached to one idler roller. The belt driving control apparatus includes a structure where a control target value of the driving motor is set so that an effective speed of the endless belt is constant and the driving motor is drive-controlled so that the control target value is satisfied.
    Type: Grant
    Filed: January 20, 2006
    Date of Patent: June 10, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Okamura, Yuji Matsuda, Hiromichi Matsuda, Toshiyuki Andoh, Nobuto Yokokawa, Ryoji Imai, Masato Yokoyama, Kazuhiko Kobayashi, Yohei Miura
  • Patent number: 7376375
    Abstract: A mark detecting unit detects a mark that is a reference position of an endless belt. An angular-displacement-error detecting unit detects an angular displacement error of an encoder caused by thickness fluctuation of the endless belt. A first calculating unit calculates a phase and a maximum amplitude to the mark. A second calculating unit calculates correction data according to a distance from the mark on the endless belt. A belt-drive control device controls a belt driving unit by adding the correction data to a preset control target value to stabilize speed fluctuation of the endless belt due to the thickness fluctuation.
    Type: Grant
    Filed: January 19, 2006
    Date of Patent: May 20, 2008
    Assignee: Ricoh Company, Limited
    Inventors: Kazuhiko Kobayashi, Hiromichi Matsuda, Toshiyuki Andoh, Nobuto Yokokawa, Ryoji Imai, Yuji Matsuda, Hiroshi Okamura, Masato Yokoyama, Yohei Miura
  • Patent number: 7373093
    Abstract: A color image forming apparatus including a plurality of photosensitive drums on which toner images of different colors are respectively formed. An endless belt confronts the plurality of photosensitive drums. A drive source drives rotation of the endless belt, or alternatively plural drive sources drive the photosensitive drums to individually rotate. A memory stores pre-measured characteristics of a color misregistration of a color image in a sub-scanning direction of the apparatus, the color image formed by transferring images from respective of the plurality of photosensitive drums. Further, a control unit changes an average running speed of the endless belt, or alternatively an average running speed of at least some of the photosensitive drums, by controlling the drive sources, to compensate for color misregistration, based on the stored characteristics of color misregistration. The belt can either transport a paper sheet or have a color image formed thereon as an intermediate transfer device.
    Type: Grant
    Filed: April 13, 2005
    Date of Patent: May 13, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Tadashi Shinohara, Masata Yokoyama, Kazuhiko Kobayashi, Yohei Miura, Toshiyuki Yakahashi, Yuji Matsuda, Jun Hosokawa, Nobuto Yokokawa, Toshiyuki Andoh