Patents by Inventor Tetsuji Nishikawa

Tetsuji Nishikawa 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: 8340552
    Abstract: A printer according to the present invention is a so-called tandem-type printer, and has a configuration that a motor gear is directly connected to an M-photoconductor driving gear and an idler gear is directly connected to a Y-photoconductor driving gear and the M-photoconductor driving gear. A diameter of the Y and M photoconductors driving gear, a distance between transfer sections of the Y and M photoconductors, a motor gear input angle, and an idler input angle are set so that an absolute value of a value obtained by subtracting 1 from an ideal amplitude ratio, which indicates a ratio of an ideal amplitude of an eccentric component of the Y-photoconductor driving gear to an actual amplitude of an eccentric component of the M-photoconductor driving gear, is equal to or less than a maximum allowable amplitude ratio.
    Type: Grant
    Filed: March 16, 2010
    Date of Patent: December 25, 2012
    Assignee: Ricoh Company, Limited
    Inventors: Yasuhiro Maehata, Tetsuji Nishikawa, Masahiro Ishida, Yasuhisa Ehara, Noriaki Funamoto, Jun Yasuda
  • Patent number: 8295736
    Abstract: In an image forming apparatus, a rotation detector detects an angular velocity or an angular displacement of a shared drive motor, or an angular velocity or an angular displacement of a photosensitive element. A drive control unit executes a process for controlling a drive speed of a drive source of the photosensitive element based on a result of detection by the rotation detector.
    Type: Grant
    Filed: December 30, 2009
    Date of Patent: October 23, 2012
    Assignee: Ricoh Company, Limited
    Inventors: Noriaki Funamoto, Yasuhisa Ehara, Tetsuji Nishikawa, Yasuhiro Maehata, Jun Yasuda
  • Patent number: 8254813
    Abstract: A multicolor imaging system includes a controller which adjusts a phase difference in rotations of photoreceptors based on information detected by a rotary position detector, and drive elements for photoreceptors which generate a velocity fluctuation in the same cycle as that of a transfer unit. The controller is configured to concurrently adjust the phases of the photoreceptors and those of the drive elements so that a registration error in four color toner image on an intermediate transfer belt is reduced to a minimum.
    Type: Grant
    Filed: May 28, 2010
    Date of Patent: August 28, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Noriaki Funamoto, Yasuhisa Ehara, Tetsuji Nishikawa, Yasuhiro Maehata, Jun Yasuda, Hiroaki Murakami
  • Patent number: 8095028
    Abstract: A driving motor for a color black is shared between a photosensitive body for the color black and a driving roller that drives an intermediate transfer belt not shown. Furthermore, a driving motor for colors yellow, magenta, and cyan is shared between photosensitive bodies for the colors yellow, magenta, and cyan. Driving of the driving motor for the colors yellow, magenta, and cyan is controlled based on a first waveform as a speed fluctuation waveform of the photosensitive body for the color black obtained when the driving motor for the color black is driven at a predetermined speed and second waveforms as speed fluctuation waveforms of the photosensitive bodies for the colors yellow, magenta, and cyan obtained when the driving motor for the colors yellow, magenta, and cyan is driven at a predetermined speed.
    Type: Grant
    Filed: June 19, 2009
    Date of Patent: January 10, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasuhisa Ehara, Noriaki Funamoto, Jun Yasuda, Tetsuji Nishikawa, Yasuhiro Maehata
  • Publication number: 20110139626
    Abstract: An object of the present invention is to provide an electrolytic copper coating that exhibits a bendability and flexibility equal to or better than those of rolled copper foil after the heat history in a circuit board fabrication process, especially after a heat history equivalent to the heat history applied when bonding with a polyimide film. The present invention provides an electrolytic copper coating and a method of manufacturing the same wherein, when performing heat treatment so that the LMP value shown in Equation 1 becomes 9000 or more, the result becomes a crystal distribution of crystal grains, having a maximum length of crystal grains after heat treatment of 10 ?m or more, of 70% or more: LMP=(T+273)*(20+Log t)??Equation 1 where, 20 is a material constant of copper, T is temperature (° C.), and t is time (hr).
    Type: Application
    Filed: June 12, 2009
    Publication date: June 16, 2011
    Applicants: FURUKAWA ELECTRIC CO., LTD., ISHIHARA CHEMICAL CO., LTD.
    Inventors: Takahiro Saito, Yuji Suzuki, Shoya Iuchi, Tetsuji Nishikawa
  • Patent number: 7938948
    Abstract: To develop stable, non-cyanide silver and silver alloy plating baths. The present invention is a silver and silver alloy plating bath, comprises: (A) a soluble salt, comprising a silver salt or a mixture of a silver salt and a salt of a metal selected from the group consisting of tin, bismuth, cobalt, antimony, iridium, indium, lead, copper, iron, zinc, nickel, palladium, platinum, and gold; and (B) at least one aliphatic sulfide compound comprising a functionality selected from the group consisting of an ether oxygen atom, a 3-hydroxypropyl group, and a hydroxypropylene group, with the proviso that the aliphatic sulfide compound does not comprise a basic nitrogen atom.
    Type: Grant
    Filed: September 3, 2009
    Date of Patent: May 10, 2011
    Assignees: Ishihara Chemical Co., Ltd., Daiwa Fine Chemicals Co., Ltd.
    Inventors: Kiyotaka Tsuji, Tetsuji Nishikawa, Takao Takeuchi, Keigo Obata, Hidemi Nawafune
  • Patent number: 7917058
    Abstract: An image forming apparatus that includes at least one process cartridge having a photosensitive element, a development unit, a toner storage unit, a driven shaft and a driven gear mounted thereon and which is detachably attachable to the apparatus from a top front side thereof, a drive shaft, a drive gear mounted on the drive shaft to couple with and drive the driven gear to transmit a driving force to the process cartridge, an upper cover opening and closing with respect to the apparatus, a front cover opening and closing with respect to the apparatus, and at least one block component to block coupling of the drive gear and the driven gear by contacting the driven shaft while interlocked with opening and closing of the upper cover. The process cartridge is detachably attachable to the apparatus from the front top side thereof by opening and closing the upper cover.
    Type: Grant
    Filed: April 18, 2008
    Date of Patent: March 29, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasuhiro Maehata, Makoto Kikura, Tetsuji Nishikawa
  • Publication number: 20110058827
    Abstract: A main controlling part is configured to choose and execute either a constant belt speed control which controls a driving motor (a driving source for an intermediate transfer belt) to move the intermediate transfer belt at a predetermined target belt speed or a constant motor speed control which rotates the driving motor at a predetermined target rotational speed according to a print command, and then, prior to a first-time print job, after executing a writing position correcting process while moving the intermediate transfer belt under the constant belt speed control, forms a color shift detecting image by switching from the constant belt speed control to the constant motor speed control, measures a difference between amounts of color shift, and executes a speed correcting process for correcting the target rotational speed of the driving motor in the constant motor speed control based on the measurement result.
    Type: Application
    Filed: September 3, 2010
    Publication date: March 10, 2011
    Applicant: Ricoh Company, Ltd.
    Inventors: Yasuhiro Maehata, Yasuhisa Ehara, Noriaki Funamoto, Tetsuji Nishikawa, Jun Yasuda, Hiroaki Murakami
  • Publication number: 20110058870
    Abstract: A sheet conveyance device for conveying a recording medium includes a fixed roller, a movable roller, an urging member, and a shock absorber, and an image forming apparatus including the sheet conveyance device. The position of the fixed roller is fixed. The movable roller is disposed opposite the fixed roller to contact the fixed roller, thereby defining a nip. The urging member urges the movable member to contact the fixed roller in the absence of the recording medium in the nip and allows the movable member to separate from the fixed roller by an amount corresponding to a thickness of a recording medium when the recording medium enters the nip. The shock absorber absorbs displacement energy generated when the urging member urges the movable roller to contact the fixed roller again after the recording medium passes through the nip.
    Type: Application
    Filed: September 2, 2010
    Publication date: March 10, 2011
    Inventors: Hiroaki Murakami, Yasuhisa Ehara, Noriaki Funamoto, Tetsuji Nishikawa, Yasuhiro Maehata, Jun Yasuda, Satoshi Araaki
  • Publication number: 20110044724
    Abstract: An image forming apparatus includes an endless belt member; a drive unit moving the endless belt member; a first detecting unit detecting a rotating speed of the drive unit; a second detecting unit detecting an endless transport speed of the endless belt member; and a control unit controlling the rotating speed of the drive unit based on a first detection signal from the first detecting unit or a second detection signal from the second detecting unit selectively depending on a selection condition. Upon selection of the first detection signal in accordance with the selection condition, the control unit corrects the rotating speed of the drive unit using the second detection signal such that an average value of the endless transport speed of the endless belt member approaches a target average value.
    Type: Application
    Filed: July 28, 2010
    Publication date: February 24, 2011
    Applicant: Ricoh Company, Ltd.
    Inventors: Noriaki Funamoto, Yasuhisa Ehara, Tetsuji Nishikawa, Yasuhiro Maehata, Jun Yasuda
  • Patent number: 7860442
    Abstract: An image fixing device for use in an image forming apparatus. The fixing device includes a fixing member which fixes a toner image on a recording medium at a nip area, a pressurizing member which pressures the recording medium toward the fixing member at the nip area, a carbon lamp which emits infrared rays, and a reflecting member which reflects the infrared rays to the nip area.
    Type: Grant
    Filed: July 3, 2007
    Date of Patent: December 28, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Tetsuji Nishikawa, Takayuki Niihara, Kazuki Suzuki, Kazunori Bannai, Makoto Kikura, Yasuhiro Maehata
  • Publication number: 20100303504
    Abstract: A multicolor imaging system includes a controller which adjusts a phase difference in rotations of photoreceptors based on information detected by a rotary position detector, and drive elements for photoreceptors which generate a velocity fluctuation in the same cycle as that of a transfer unit. The controller is configured to concurrently adjust the phases of the photoreceptors and those of the drive elements so that a registration error in four color toner image on an intermediate transfer belt is reduced to a minimum.
    Type: Application
    Filed: May 28, 2010
    Publication date: December 2, 2010
    Inventors: Noriaki Funamoto, Yasuhisa Ehara, Tetsuji Nishikawa, Yasuhiro Maehata, Jun Yasuda, Hiroaki Murakami
  • Publication number: 20100239318
    Abstract: A printer according to the present invention is a so-called tandem-type printer, and has a configuration that a motor gear is directly connected to an M-photoconductor driving gear and an idler gear is directly connected to a Y-photoconductor driving gear and the M-photoconductor driving gear. A diameter of the Y and M photoconductors driving gear, a distance between transfer sections of the Y and M photoconductors, a motor gear input angle, and an idler input angle are set so that an absolute value of a value obtained by subtracting 1 from an ideal amplitude ratio, which indicates a ratio of an ideal amplitude of an eccentric component of the Y-photoconductor driving gear to an actual amplitude of an eccentric component of the M-photoconductor driving gear, is equal to or less than a maximum allowable amplitude ratio.
    Type: Application
    Filed: March 16, 2010
    Publication date: September 23, 2010
    Inventors: Yasuhiro Maehata, Tetsuji Nishikawa, Masahiro Ishida, Yasuhisa Ehara, Noriaki Funamoto, Jun Yasuda
  • Publication number: 20100226676
    Abstract: In an image forming apparatus, a servomotor is used as a shared driving motor. A motor driver includes a gain changing unit that changes proportional gain. When a monochrome mode is selected, a driving control unit sets the proportional gain lower than a value that is set in a color mode.
    Type: Application
    Filed: February 25, 2010
    Publication date: September 9, 2010
    Inventors: Noriaki Funamoto, Yasuhisa Ehara, Tetsuji Nishikawa, Yasuhiro Maehata, Jun Yasuda
  • Publication number: 20100183322
    Abstract: In an image forming apparatus, a rotation detector detects an angular velocity or an angular displacement of a shared drive motor, or an angular velocity or an angular displacement of a photosensitive element. A drive control unit executes a process for controlling a drive speed of a drive source of the photosensitive element based on a result of detection by the rotation detector.
    Type: Application
    Filed: December 30, 2009
    Publication date: July 22, 2010
    Inventors: Noriaki Funamoto, Yasuhisa Ehara, Tetsuji Nishikawa, Yasuhiro Maehata, Jun Yasuda
  • Patent number: 7706723
    Abstract: An image forming apparatus includes a plurality of image carriers, a drive mechanism, a plurality of drive force transmission gears, a phase difference detector, and a shift unit. The plurality of image carriers forms images of separate colors. The drive mechanism including a single drive unit for driving the plurality of image carriers simultaneously. The plurality of drive force transmission gears, provided for each of the image carriers, transmits a driving force from the drive unit to the image carriers. The phase difference detector detects a phase difference in drive speed among the image carriers. The shift unit, provided for each of the plurality of drive force transmission gears, meshes or unmeshes the drive force transmission gear to the drive mechanism. The shift unit is activated to correct any phase difference in drive speed of the image carriers based on a detection result detected with the phase difference detector.
    Type: Grant
    Filed: October 12, 2007
    Date of Patent: April 27, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Masahiro Ishida, Kazuki Suzuki, Tetsuji Nishikawa, Yasuhiro Maehata, Takayuki Niihara, Makoto Kikura
  • Patent number: 7702252
    Abstract: A connector connects a rotatable body including an attachment hole and an engaging groove, and a shaft pressed into the attachment hole to integrally rotate. The connector includes at least one pin configured to fit in the engaging groove; and a screw having a head configured to be pressed against the rotatable body either directly or via another member. The at least one pin is fixed on the shaft and extends in a radial direction of the shaft to penetrate the shaft. The screw is screwed into a screw hole on an end face of the shaft and is tightened to press the at least one pin against a surface of the engaging groove.
    Type: Grant
    Filed: July 2, 2007
    Date of Patent: April 20, 2010
    Assignee: Ricoh Company, Limited
    Inventors: Yasuhiro Maehata, Kazuki Suzuki, Takayuki Niihara, Makoto Kikura, Tetsuji Nishikawa, Masahiro Ishida
  • Publication number: 20090321269
    Abstract: To develop stable, non-cyanide silver and silver alloy plating baths. The present invention is a silver and silver alloy plating bath, comprises: (A) a soluble salt, comprising a silver salt or a mixture of a silver salt and a salt of a metal selected from the group consisting of tin, bismuth, cobalt, antimony, iridium, indium, lead, copper, iron, zinc, nickel, palladium, platinum, and gold; and (B) at least one aliphatic sulfide compound comprising a functionality selected from the group consisting of an ether oxygen atom, a 3-hydroxypropyl group, and a hydroxypropylene group, with the proviso that the aliphatic sulfide compound does not comprise a basic nitrogen atom.
    Type: Application
    Filed: September 3, 2009
    Publication date: December 31, 2009
    Applicants: ISHIHARA CHEMICAL CO., LTD., DAIWA FINE CHEMICALS CO., LTD.
    Inventors: Kiyotaka TSUJI, Tetsuji NISHIKAWA, Takao TAKEUCHI, Keigo OBATA, Hidemi NAWAFUNE
  • Publication number: 20090317109
    Abstract: A driving motor for a color black is shared between a photosensitive body for the color black and a driving roller that drives an intermediate transfer belt not shown. Furthermore, a driving motor for colors yellow, magenta, and cyan is shared between photosensitive bodies for the colors yellow, magenta, and cyan. Driving of the driving motor for the colors yellow, magenta, and cyan is controlled based on a first waveform as a speed fluctuation waveform of the photosensitive body for the color black obtained when the driving motor for the color black is driven at a predetermined speed and second waveforms as speed fluctuation waveforms of the photosensitive bodies for the colors yellow, magenta, and cyan obtained when the driving motor for the colors yellow, magenta, and cyan is driven at a predetermined speed.
    Type: Application
    Filed: June 19, 2009
    Publication date: December 24, 2009
    Inventors: Yasuhisa Ehara, Noriaki Funamoto, Jun Yasuda, Tetsuji Nishikawa, Yasuhiro Maehata
  • Patent number: 7628903
    Abstract: A silver and silver alloy plating bath, includes (A) a soluble salt, having a silver salt or a mixture of a silver salt and a salt of a metal such as tin, bismuth, indium, lead, and the like; and (B) a particular aliphatic sulfide compound, such as thiobis(diethyleneglycol), dithiobis(triglycerol), 3,3?-thiodipropanol, thiodiglycerin, 3,6-dithiooctane-1,8-diol, and the like, which contain at least one or more of an ether oxygen atom, a 1-hydroxypropyl group, a hydroxypropylene group, or two or more of a sulfide bond in the molecule, and not containing a basic nitrogen atom.
    Type: Grant
    Filed: May 2, 2000
    Date of Patent: December 8, 2009
    Assignees: Ishihara Chemical Co., Ltd., Daiwa Fine Chemicals Co., Ltd.
    Inventors: Kiyotaka Tsuji, Tetsuji Nishikawa, Takao Takeuchi, Keigo Obata, Hidemi Nawafune