Patents by Inventor Tomohiko Koda

Tomohiko Koda 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: 9050803
    Abstract: A liquid ejection head includes nozzles, a channel member, a common liquid chamber member, a damper member, a damper chamber formation member, a first adhesive, and a second adhesive. The channel member includes individual liquid chambers communicated with the nozzles. The common liquid chamber member forms a common liquid chamber to supply liquid to the individual liquid chambers. The damper member has a deformable area forming a portion of a wall of the common liquid chamber. The damper chamber formation member forms a damper chamber disposed opposing the common liquid chamber via the deformable area. The first adhesive is disposed between the damper member and the common liquid chamber member. The second adhesive is disposed between the damper member and the damper chamber formation member. The deformable area of the damper member has a peripheral portion fringed with the first adhesive and the second adhesive.
    Type: Grant
    Filed: July 1, 2013
    Date of Patent: June 9, 2015
    Assignee: RICOH COMPANY, LTD.
    Inventor: Tomohiko Koda
  • Patent number: 9009973
    Abstract: A method for manufacturing a liquid discharging head, the method including forming a plurality of nozzles that discharge liquid droplets, forming a plurality of piezoelectric elements that generate pressure for discharging liquid droplets from the respective nozzles; and performing a repolarization process on the piezoelectric elements to set non-uniformity of the droplet discharging characteristics of the nozzles to be in a predetermined range by combining adjustment of a polarization sensitivity and adjustment of a polarization voltage for each of the piezoelectric elements.
    Type: Grant
    Filed: November 19, 2010
    Date of Patent: April 21, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Takahiro Yamada, Tomohiko Koda, Hitoshi Kida
  • Patent number: 8888260
    Abstract: A liquid-jet head includes nozzles ejecting liquid drops, individual liquid chambers in communication with the corresponding nozzles, a common liquid chamber supplying the liquid to the individual liquid chambers, and a filter member filtering the liquid inside the common liquid chamber. The filter member includes a thin layer having pores and a thick layer on a circumferential part of the thin layer, the thick layer being bonded to the first common liquid chamber member; the thin layer includes a first surface having the thick layer and a second surface opposite to the first surface, a circumferential part of the second surface being bonded to the second common liquid chamber member with an adhesive; and part of or all the pores in the circumferential part of the second surface are exposed in a direction toward the thick layer, and the adhesive overflows into the pores.
    Type: Grant
    Filed: February 27, 2013
    Date of Patent: November 18, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Keisuke Hayashi, Tomohiko Koda
  • Patent number: 8777346
    Abstract: An ink-jet printing method includes the steps of dividing multiple ink droplet discharging pulses into two or more groups in an ink droplet discharging order, providing the multiple ink droplet discharging pulses to a pressure generator per scan line time, and discharging ink droplets from an ink droplet discharge head in accordance with the multiple ink droplet discharging pulses. The method further includes the steps of combining ink droplets of a former group as a first combined ink droplet, combining ink droplets of a latter group as a second combination droplet, combining the second combined ink droplet of the latter group with that of former group before the ink droplets reach a target, and maintaining a prescribed amount of ink droplets landing on the target by decreasing the number of ink droplet discharging pulses.
    Type: Grant
    Filed: August 13, 2012
    Date of Patent: July 15, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Takashi Satou, Tomohiko Koda, Ryouta Matsufuji
  • Publication number: 20140009544
    Abstract: A liquid ejection head includes nozzles, a channel member, a common liquid chamber member, a damper member, a damper chamber formation member, a first adhesive, and a second adhesive. The channel member includes individual liquid chambers communicated with the nozzles. The common liquid chamber member forms a common liquid chamber to supply liquid to the individual liquid chambers. The damper member has a deformable area forming a portion of a wall of the common liquid chamber. The damper chamber formation member forms a damper chamber disposed opposing the common liquid chamber via the deformable area. The first adhesive is disposed between the damper member and the common liquid chamber member. The second adhesive is disposed between the damper member and the damper chamber formation member. The deformable area of the damper member has a peripheral portion fringed with the first adhesive and the second adhesive.
    Type: Application
    Filed: July 1, 2013
    Publication date: January 9, 2014
    Applicant: RICOH COMPANY, LTD.
    Inventor: Tomohiko Koda
  • Publication number: 20130242012
    Abstract: A liquid-jet head includes nozzles ejecting liquid drops, individual liquid chambers in communication with the corresponding nozzles, a common liquid chamber supplying the liquid to the individual liquid chambers, and a filter member filtering the liquid inside the common liquid chamber. The filter member includes a thin layer having pores and a thick layer on a circumferential part of the thin layer, the thick layer being bonded to the first common liquid chamber member; the thin layer includes a first surface having the thick layer and a second surface opposite to the first surface, a circumferential part of the second surface being bonded to the second common liquid chamber member with an adhesive; and part of or all the pores in the circumferential part of the second surface are exposed in a direction toward the thick layer, and the adhesive overflows into the pores.
    Type: Application
    Filed: February 27, 2013
    Publication date: September 19, 2013
    Applicant: RICOH COMPANY, LTD.
    Inventors: Keisuke Hayashi, Tomohiko Koda
  • Publication number: 20130038651
    Abstract: An ink-jet printing method includes the steps of dividing multiple ink droplet discharging pulses into two or more groups in an ink droplet discharging order, providing the multiple ink droplet discharging pulses to a pressure generator per scan line time, and discharging ink droplets from an ink droplet discharge head in accordance with the multiple ink droplet discharging pulses. The method further includes the steps of combining ink droplets of a former group as a first combined ink droplet, combining ink droplets of a latter group as a second combination droplet, combining the second combined ink droplet of the latter group with that of former group before the ink droplets reach a target, and maintaining a prescribed amount of ink droplets landing on the target by decreasing the number of ink droplet discharging pulses.
    Type: Application
    Filed: August 13, 2012
    Publication date: February 14, 2013
    Applicant: RICOH COMPANY, LTD.
    Inventors: Takashi SATOU, Tomohiko KODA, Ryouta MATSUFUJI
  • Patent number: 8366242
    Abstract: A liquid-ejection head unit includes a head, an electric-circuit board, electronic components, and a storage tank. The head includes a frame member and ejects droplets of liquid. The electronic components are mounted on the electric-circuit board and connected to the head. The storage tank stores liquid supplied to the head. The electric-circuit board is disposed between the frame member of the head and the storage tank to form a single multi-layered structure. The electronic components of the electric-circuit board are accommodated in at least one of a first internal space defined by the frame member of the head and the electric-circuit board and a second internal space defined by the electric-circuit board and the storage tank.
    Type: Grant
    Filed: June 29, 2010
    Date of Patent: February 5, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Tomohiko Koda, Kenichi Yoshimura, Tomiyoshi Takano, Mitsuru Kawakami, Masami Iwama
  • Patent number: 8348407
    Abstract: A liquid ejection head includes nozzles, separate chambers, a common chamber, inlet portions, a filter unit, and ribs. Droplets of liquid are ejected from the nozzles. The separate chambers are communicated with the nozzles. The inlet portions are communicated with the corresponding separate chambers. Liquid is supplied from the common chamber to the separate chambers through the inlet portions. The filter unit is disposed between the inlet portions and the common chamber to filter liquid in an area across the separate chambers in a first direction in which the nozzles are arrayed. The ribs are disposed in the filter unit at intervals corresponding in size to at least two of the separate chambers in the first direction to partition the filter unit. The inlet portions are communicated in the first direction with each other in at least one portion of each of the inlet portions facing the filter unit.
    Type: Grant
    Filed: June 24, 2010
    Date of Patent: January 8, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Ryouta Matsufuji, Hideyuki Makita, Tadashi Mimura, Satoru Tobita, Tomohiko Koda
  • Patent number: 8087761
    Abstract: A liquid discharging head includes: a plurality of nozzles that discharge liquid droplets; and a plurality of piezoelectric elements that generate pressure for discharging liquid droplets from the respective nozzles, wherein the piezoelectric elements are performed with repolarization process to set non-uniformity of the droplet discharging characteristics of the nozzles to be in a predetermined range by combining adjustment of a polarization sensitivity and adjustment of a polarization voltage for each of the piezoelectric elements.
    Type: Grant
    Filed: June 19, 2008
    Date of Patent: January 3, 2012
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Takahiro Yamada, Tomohiko Koda, Hitoshi Kida
  • Patent number: 7914126
    Abstract: In an ink jet head manufacturing device, first and second diodes are arranged on a path extending from a gate of a control unit to an individual electrode of an ink-pressure control part in an ink jet head, the first diode allowing a current from the individual electrode of the ink-pressure control part to flow into a first wiring, and the second diode allowing a current from a second wiring to flow into the individual electrode of the ink-pressure control part. A short-circuit unit is arranged to short-circuit the first wiring and the second wiring when depolarization or polarization of the ink-pressure control part is performed.
    Type: Grant
    Filed: March 27, 2009
    Date of Patent: March 29, 2011
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Hitoshi Kida, Takahiro Yamada, Tomohiko Koda
  • Publication number: 20110061216
    Abstract: A method for manufacturing a liquid discharging head, the method including forming a plurality of nozzles that discharge liquid droplets, forming a plurality of piezoelectric elements that generate pressure for discharging liquid droplets from the respective nozzles; and performing a repolarization process on the piezoelectric elements to set non-uniformity of the droplet discharging characteristics of the nozzles to be in a predetermined range by combining adjustment of a polarization sensitivity and adjustment of a polarization voltage for each of the piezoelectric elements.
    Type: Application
    Filed: November 19, 2010
    Publication date: March 17, 2011
    Applicant: RICOH PRINTING SYSTEMS, LTD.
    Inventors: Takahiro YAMADA, Tomohiko KODA, Hitoshi KIDA
  • Patent number: 7887151
    Abstract: An image forming apparatus having a liquid ejection head including a plurality of nozzles for ejecting droplets and a plurality of piezoelectric elements for generating a pressure for discharging droplets in respective nozzles. The image forming apparatus includes a polarization adjustment unit that performs a polarization adjustment in parallel for adjustment of target nozzles.
    Type: Grant
    Filed: February 20, 2008
    Date of Patent: February 15, 2011
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Takahiro Yamada, Hitoshi Kida, Tomohiko Koda
  • Publication number: 20100328400
    Abstract: A liquid-ejection head unit includes a head, an electric-circuit board, electronic components, and a storage tank. The head includes a frame member and ejects droplets of liquid. The electronic components are mounted on the electric-circuit board and connected to the head. The storage tank stores liquid supplied to the head. The electric-circuit board is disposed between the frame member of the head and the storage tank to form a single multi-layered structure. The electronic components of the electric-circuit board are accommodated in at least one of a first internal space defined by the frame member of the head and the electric-circuit board and a second internal space defined by the electric-circuit board and the storage tank.
    Type: Application
    Filed: June 29, 2010
    Publication date: December 30, 2010
    Applicant: RICOH COMPANY, LTD.
    Inventors: Tomohiko Koda, Kenichi Yoshimura, Tomiyoshi Takano, Mitsuru Kawakami, Masami Iwama
  • Publication number: 20100328409
    Abstract: A liquid ejection head includes nozzles, separate chambers, a common chamber, inlet portions, a filter unit, and ribs. Droplets of liquid are ejected from the nozzles. The separate chambers are communicated with the nozzles. The inlet portions are communicated with the corresponding separate chambers. Liquid is supplied from the common chamber to the separate chambers through the inlet portions. The filter unit is disposed between the inlet portions and the common chamber to filter liquid in an area across the separate chambers in a first direction in which the nozzles are arrayed. The ribs are disposed in the filter unit at intervals corresponding in size to at least two of the separate chambers in the first direction to partition the filter unit. The inlet portions are communicated in the first direction with each other in at least one portion of each of the inlet portions facing the filter unit.
    Type: Application
    Filed: June 24, 2010
    Publication date: December 30, 2010
    Applicant: RICOH COMPANY, LTD.
    Inventors: Ryouta MATSUFUJI, Hideyuki Makita, Tadashi Mimura, Satoru Tobita, Tomohiko Koda
  • Patent number: 7695114
    Abstract: A disclosed inkjet head includes an ink channel unit formed by stacking a channel plate having a nozzle hole formed therein, a channel plate having a pressure chamber formed therein, and a channel plate having a restrictor formed therein and by bonding the channel plates together by diffusion bonding, which channel plates have substantially the same thickness; a pressure generating source attached to a surface of the ink channel unit and configured to generate pressure to jet ink; and a housing formed by stacking housing plates and by bonding the housing plates together by diffusion bonding and configured to hold the ink channel unit, which housing plates have substantially the same thickness as that of the channel plates.
    Type: Grant
    Filed: February 20, 2007
    Date of Patent: April 13, 2010
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Tomohiko Koda, Satoru Tobita, Takashi Sato, Yoshinari Suzuki
  • Patent number: 7681987
    Abstract: An inkjet recording head includes a nozzle plate, chamber plate, and a diaphragm plate. The nozzle plate includes a plurality of nozzles for ejecting ink droplets, a plurality of connecting channels in communication with the nozzles and pressure chambers. The nozzles are formed in a row at a uniform pitch. The connecting channels extend from the nozzles alternately in opposite directions in a staggered formation and are offset a prescribed angle to a direction orthogonal to the row of nozzles. The chamber plate includes the pressure chambers, restrictors, and common ink chambers formed therein. Each pressure chamber has an elongated shape extending in a direction orthogonal to the row of nozzles. The pressure chambers are formed in rows, one on either side of the row of nozzles, so that the pressure chambers in one row oppose the corresponding pressure chambers in the other row. The diaphragm plate has a vibration plate that seals the pressure chambers.
    Type: Grant
    Filed: March 1, 2006
    Date of Patent: March 23, 2010
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Satoru Tobita, Ryouta Matsufuji, Tomohiko Koda
  • Publication number: 20090244202
    Abstract: In an ink jet head manufacturing device, first and second diodes are arranged on a path extending from a gate of a control unit to an individual electrode of an ink-pressure control part in an ink jet head, the first diode allowing a current from the individual electrode of the ink-pressure control part to flow into a first wiring, and the second diode allowing a current from a second wiring to flow into the individual electrode of the ink-pressure control part. A short-circuit unit is arranged to short-circuit the first wiring and the second wiring when depolarization or polarization of the ink-pressure control part is performed.
    Type: Application
    Filed: March 27, 2009
    Publication date: October 1, 2009
    Inventors: Hitoshi KIDA, Takahiro YAMADA, Tomohiko KODA
  • Patent number: 7494210
    Abstract: An inkjet recording head includes a base member, an ink channel unit, a plurality of piezoelectric elements, and a dynamic vibration absorber. The ink channel unit is formed with a plurality of nozzle holes and a plurality of ink pressure chambers. The ink channel unit includes a diaphragm that defines part of each ink pressure chamber. Each piezoelectric element has one end fixed to the base member and another end attached to the diaphragm. Each piezoelectric element generates displacement in a displacement direction for deforming the diaphragm to eject ink droplets through a corresponding one of the plurality of nozzle holes. The dynamic vibration absorber is mounted on the base member for damping vibrations of the base member due to a resonance, the resonance occurring in a frequency range less than or equal to a predetermined frequency.
    Type: Grant
    Filed: July 13, 2005
    Date of Patent: February 24, 2009
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Takahiro Yamada, Toshiharu Sumiya, Tomohiko Koda, Shinya Kobayashi, Satoru Tobita
  • Publication number: 20080316280
    Abstract: A liquid discharging head includes: a plurality of nozzles that discharge liquid droplets; and a plurality of piezoelectric elements that generate pressure for discharging liquid droplets from the respective nozzles, wherein the piezoelectric elements are performed with repolarization process to set non-uniformity of the droplet discharging characteristics of the nozzles to be in a predetermined range by combining adjustment of a polarization sensitivity and adjustment of a polarization voltage for each of the piezoelectric elements.
    Type: Application
    Filed: June 19, 2008
    Publication date: December 25, 2008
    Applicant: RICOH PRINTING SYSTEMS, LTD.
    Inventors: Tokahiro Yamada, Tomohiko Koda, Hitoshi Kida