Patents by Inventor Takuro Sekiya

Takuro Sekiya 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).

  • Publication number: 20020057310
    Abstract: In an apparatus producing a high-quality and high-resolution image having high water and light resistances with an orifice having a diameter less than &phgr;25 &mgr;m (less than 500 &mgr;m2 in terms of cross-sectional area of the orifice) by use of a fine particle dispersion recording composition, nozzle clogging can be prevented. A recording is accomplished by a liquid jet recording apparatus for ejecting a recording composition including dispersed fine particles from a small orifice toward a receiving medium, wherein a size Dp of the fine particles and a diameter Do of the small orifice are determined by a relationship 0.001≦Dp/Do≦0.01.
    Type: Application
    Filed: November 19, 2001
    Publication date: May 16, 2002
    Inventor: Takuro Sekiya
  • Patent number: 6338545
    Abstract: In an apparatus producing a high-quality and high-resolution image having high water and light resistances with an orifice having a diameter less than &phgr;25 &mgr;m (less than 500 &mgr;m2 in terms of cross-sectional area of the orifice) by use of a fine particle dispersion recording composition, nozzle clogging can be prevented. A recording is accomplished by a liquid jet recording apparatus for ejecting a recording composition including dispersed fine particles from a small orifice toward a receiving medium, wherein a size Dp of the fine particles and a diameter Do of the small orifice are determined by a relationship 0.001≦Dp/Do≦0.01.
    Type: Grant
    Filed: July 8, 1999
    Date of Patent: January 15, 2002
    Assignee: Ricoh Company, Ltd.
    Inventor: Takuro Sekiya
  • Publication number: 20010024227
    Abstract: The present invention relates to an electron-emitting device and an image display apparatus in which the electron-emitting device is provided. In the electron-emitting device, a substrate has sides in two orthogonal first directions. A plurality of pairs of electrodes are disposed on the substrate. A conductive thin film is disposed between each of the electrode pairs. A plurality of surface conduction electron-emitting elements are disposed in the conductive thin film by discharging drops of a source material of the film thereto, each electron-emitting element spaced apart from the opposing electrodes of one of the electrode pairs. The electron-emitting elements are arrayed in a matrix formation, the matrix having rows and columns in two orthogonal second directions, the electron-emitting elements being disposed such that the second directions of the matrix are parallel to the first directions of the substrate.
    Type: Application
    Filed: February 26, 2001
    Publication date: September 27, 2001
    Applicant: Ricoh Company, Ltd.
    Inventor: Takuro Sekiya
  • Patent number: 6227639
    Abstract: An ink jet recording method includes the steps of inputting a set of driving pulses to a heater element so that the heater element is repeatedly activated by the driving pulses, repeatedly generating a bubble in ink in an ink path in accordance with repeated activation of the heater element, and separately jetting ink droplets from an ink jetting orifice due to the bubble repeatedly generated in the ink, a number of the ink droplets being equal to a number of the driving pulses input as a set to the heater element, the ink droplets jetted from the ink jetting orifice forming a single dot on a recording medium, wherein a time interval at which the driving pulses are input to the heater element is equal to or greater than 4T, T being a time period from a time at which the inputting of the pulses to the heater element starts to a time at which the bubble reaches a maximum size, and each ink droplet is a slender pillar so that a length of each ink droplet is at least three times as great as a diameter thereof.
    Type: Grant
    Filed: February 25, 1998
    Date of Patent: May 8, 2001
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuro Sekiya, Kyuhachiro Iwasaki
  • Patent number: 6193348
    Abstract: A liquid jet recording apparatus for jetting ink droplets to a recording medium in accordance with image data on demand so that an image having pixels corresponding to the image data is formed on the recording medium. The liquid jet recording apparatus includes ink jetting orifices from which ink droplets are jetted. An area of each of ink jetting orifices is equal to or less than 500 &mgr;m2. Control means controls a frequency with which the ink droplets are jetted to fall within a range from 8 KHz to 40 KHz and a number of ink droplets for each pixel of the image formed on the recording medium based on the image data under a condition in which the number of ink droplets is equal to or less than twenty.
    Type: Grant
    Filed: February 25, 1998
    Date of Patent: February 27, 2001
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuro Sekiya, Kyuhachiro Iwasaki
  • Patent number: 6039425
    Abstract: An ink jet recording method includes the steps of inputting a set of driving pulses to a heater element so that the heater element is repeatedly activated by the driving pulses, repeatedly generating a bubble in ink in an ink path in accordance with repeated activation of the heater element, and separately jetting ink droplets from an ink jetting orifice due to the bubble repeatedly generated in the ink, a number of the ink droplets being equal to a number of the driving pulses input as a set to the heater element, the ink droplets jetted from the ink jetting orifice forming a single dot on a recording medium, wherein a time interval at which the driving pulses are input to the heater element is equal to or greater than 4T, T being a time period from a time at which the inputting of the pulses to the heater element starts to a time at which the bubble reaches a maximum size, and each ink droplet is a slender pillar so that a length of each ink droplet is at least three times as great as a diameter thereof.
    Type: Grant
    Filed: March 19, 1997
    Date of Patent: March 21, 2000
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuro Sekiya, Kyuhachiro Iwasaki
  • Patent number: 5877786
    Abstract: An ink jet recording method includes the steps of inputting a set of driving pulses to a heater element so that the heater element is repeatedly activated by the driving pulses, repeatedly generating a bubble in ink in an ink path in accordance with repeated activation of the heater element, and separately jetting ink droplets from an ink jetting orifice due to the bubble repeatedly generated in the ink, a number of the ink droplets being equal to a number of the driving pulses input as a set to the heater element, the ink droplets jetted from the ink jetting orifice forming a single dot on a recording medium, wherein a time interval at which the driving pulses are input to the heater element is equal to or greater than 4T, T being a time period from a time at which the inputting of the pulses to the heater element starts to a time at which the bubble reaches a maximum size, and each ink droplet is a slender pillar so that a length of each ink droplet is at least three times as great as a diameter thereof.
    Type: Grant
    Filed: October 29, 1996
    Date of Patent: March 2, 1999
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuro Sekiya, Kyuhachiro Iwasaki
  • Patent number: 5754202
    Abstract: An ink jet recording apparatus includes a recording head for ejecting droplets of ink and a driving circuit for driving the recording head. The recording head includes a base, a plate on which a plurality of openings are formed; an ink chamber to be filled with ink being formed between the base and the plate; and heater elements, provided in the ink chamber so as to face the openings of the plate, each of which heater elements supplies heat energy to ink adjacent thereto so that the air bubble is generated on each of the heater elements and so that the air bubble grows toward a corresponding one of the openings. An area of each of the openings of the plate is greater than an area each of the heater elements. When the driving circuit activates each of the heater elements, a droplet of ink is ejected due to the air bubble from the corresponding one of the openings of the plate.
    Type: Grant
    Filed: November 26, 1996
    Date of Patent: May 19, 1998
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuro Sekiya, Takayuki Yamaguchi, Mitsuru Shingyouchi, Makoto Obu, Michio Umezawa, Tetsuro Hirota, Takesada Hirose, Hideki Ohtsuki, Toshihiro Takesue
  • Patent number: 5729257
    Abstract: An ink jet recording method includes the steps of inputting a set of driving pulses to a heater element so that the heater element is repeatedly activated by the driving pulses, repeatedly generating a bubble in ink in an ink path in accordance with repeated activation of the heater element, and separately jetting ink droplets from an ink jetting orifice due to the bubble repeatedly generated in the ink, a number of the ink droplets being equal to a number of the driving pulses input as a set to the heater element, the ink droplets jetted from the ink jetting orifice forming a single dot on a recording medium, wherein a time interval at which the driving pulses are input to the heater element is equal to or greater than 4T, T being a time period from a time at which the inputting of the pulses to the heater element starts to a time at which the bubble reaches a maximum size, and each ink droplet is a slender pillar so that a length of each ink droplet is at least three times as great as a diameter thereof.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: March 17, 1998
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuro Sekiya, Kyuhachiro Iwasaki
  • Patent number: 5657060
    Abstract: An ink jet recording method includes the steps of inputting a set of driving pulses to a heater element so that the heater element is repeatedly activated by the driving pulses, repeatedly generating a bubble in ink in an ink path in accordance with repeated activation of the heater element, and separately jetting ink droplets from an ink jetting orifice due to the bubble repeatedly generated in the ink, a number of the ink droplets being equal to a number of the driving pulses input as a set to the heater element, the ink droplets jetted from the ink jetting orifice forming a single dot on a recording medium, wherein a time interval at which the driving pulses are input to the heater element is equal to or greater than 4T, T being a time period from a time at which the inputting of the pulses to the heater element starts to a time at which the bubble reaches a maximum size, and each ink droplet is a slender pillar so that a length of each ink droplet is at least three times as great as a diameter thereof.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: August 12, 1997
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuro Sekiya, Kyuhachiro Iwasaki
  • Patent number: 5610637
    Abstract: An ink jet recording method includes the steps of inputting a set of driving pulses to a heater element so that the heater element is repeatedly activated by the driving pulses, repeatedly generating a bubble in ink in an ink path in accordance with repeated activation of the heater element, and separately jetting ink droplets from an ink jetting orifice due to the bubble repeatedly generated in the ink, a number of the ink droplets being equal to a number of the driving pulses input as a set to the heater element, the ink droplets jetted from the ink jetting orifice forming a single dot on a recording medium, wherein a time interval at which the driving pulses are input to the heater element is equal to or greater than 4T, T being a time period from a time at which the inputting of the pulses to the heater element starts to a time at which the bubble reaches a maximum size, and each ink droplet is a slender pillar so that a length of each ink droplet is at least three times as great as a diameter thereof.
    Type: Grant
    Filed: September 27, 1993
    Date of Patent: March 11, 1997
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuro Sekiya, Kyuhachiro Iwasaki
  • Patent number: 5600356
    Abstract: A liquid jet recording head includes a liquid path member having a plurality of liquid flow paths, each of the liquid flow paths being filled with a recording liquid, an orifice being formed at an end of each of the liquid flow paths, and a heater base member having a plurality of heater members and a plurality of radiator members. The heater base member is connected to the liquid path member, each of the heater members having a heater portion, the heater portion generating heat in accordance with a power supplied to it. Each of the radiator members is thermally coupled to the heater portion of one of the heater members so that the amount of heat transmitted from the heater portion to the recording liquid on the heater portion changes in a predetermined direction.
    Type: Grant
    Filed: December 28, 1994
    Date of Patent: February 4, 1997
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuro Sekiya, Takashi Kimura, Masanori Horike, Shuji Motomura, Masami Kadonaga
  • Patent number: 5420618
    Abstract: An ink jet recording apparatus is provided with an ink jet recording head which includes at least one nozzle for ejecting ink, a heating layer, and a ground electrode and a plurality of control electrodes electrically connected to the heating layer, and a thermal energy action part, formed in the heating layer in correspondence with the nozzle, for heating the ink and causing a state transition so as to eject the ink from the nozzle when a voltage is applied across at least one pair of the ground electrode and the control electrode. The ground electrode electrically connects to the heating layer within a region of the thermal energy action part, and the control electrodes electrically connects to the heating layer outside the region of the thermal energy action part.
    Type: Grant
    Filed: May 8, 1992
    Date of Patent: May 30, 1995
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuro Sekiya, Mitsuru Shingyouchi, Eiko Suzuki, Masami Kadonaga
  • Patent number: 5412413
    Abstract: A liquid jet recording head includes a base member, a liquid layer maintained on the base member and a plurality of heater elements, arranged in a line on the base member, for supplying energy to liquid adjacent thereto, the energy operation portions being put under the liquid layer. A method for making a liquid drop fly from the liquid jet recording head onto a recording sheet so that a dot image is formed on the recording sheet includes steps of (a) generating a bubble in the liquid to which the energy is supplied by each of energy operation portions in accordance with image data; (b) making the bubble grow up until a predetermined size of the bubble is obtained; (c) contracting the bubble under a condition where each of the energy portions supplies no energy to the liquid in which the bubble is formed; and (d) making the bubble disappear into the liquid.
    Type: Grant
    Filed: November 4, 1992
    Date of Patent: May 2, 1995
    Assignee: Ricoh Co., Ltd.
    Inventors: Takuro Sekiya, Takashi Kimura, Masanori Horike, Yoshio Watanabe, Shuji Motomura, Eiko Suzuki, Takayuki Yamaguchi, Masami Kadonaga
  • Patent number: 5389962
    Abstract: An ink jet recording head assembly includes: a base member having a plurality of enclosures, a top of each of the enclosures having an opening; a mechanism for supplying ink to each of the enclosures via the opening at the top thereof and for maintaining the ink at a predetermined depth; and a heater element which is provided in each of the enclosures under the ink supplied via the opening, the heater element heating the ink in each of the enclosures so that a bubble is generated in the ink; wherein an ink drop is jetted from a surface of the ink due to the bubble generated in the ink.
    Type: Grant
    Filed: December 9, 1991
    Date of Patent: February 14, 1995
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuro Sekiya, Mitsuru Shingyouchi, Takashi Kimura, Takayuki Yamaguchi, Yoshio Watanabe, Shuji Motomura, Eiko Suzuki, Masami Kadonaga
  • Patent number: 5293182
    Abstract: A liquid jet recording head includes a heater element which comprises a heat reserve layer, a resistance layer formed on the heat reserve layer, electrodes electrically connected to the resistance layer, the resistance layer generating heat when an electrical current is supplied to the resistance layer via the electrodes, and a protection layer stacked on the resistance layer, the heat generated by the resistance layer being transmitted to the liquid via the protection layer. The heater element has a special part in which a width of the resistance layer is greater than that thereof in a normal part of the heater element, the special part including a position where the bubble disappears, so that a electric current density in the resistance layer in the special part is less than that thereof in the normal part.
    Type: Grant
    Filed: February 11, 1992
    Date of Patent: March 8, 1994
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuro Sekiya, Takashi Kimura, Mitsuru Shingyouchi
  • Patent number: 5172139
    Abstract: A liquid jet recording head which is used for generating bubbles in a writing liquid of a liquid chamber and discharging droplets of the writing liquid to a recording sheet in an ink-jet printer. The liquid jet recording head includes an orifice from which the writing liquid is discharged, a liquid discharge path leading to the orifice, the orifice communicating with the liquid chamber. The liquid jet recording head further includes a plurality of energy generating elements for generating energy to produce the bubbles in the writing liquid, the plurality of energy generating elements being provided within the liquid chamber and corresponding to a single orifice. Each of the energy generating elements has an energy transmitting surface which is approximately perpendicular to the liquid discharge path, and one or more combinations of the energy generating elements which are independently driven by the drive control mechanism to allow gradation recording on the recording sheet.
    Type: Grant
    Filed: May 4, 1990
    Date of Patent: December 15, 1992
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuro Sekiya, Takashi Kimura, Tomoaki Nakano
  • Patent number: 4990939
    Abstract: A bubble jet printer head comprises a base plate, an ink chamber provided on the phase plate, a device for supplying ink to the ink chamber, an ink passage provided on the base plate from the ink chamber to an orifice at a front end, and a heating element at the ink passage for heating the ink to form a bubble.
    Type: Grant
    Filed: August 24, 1989
    Date of Patent: February 5, 1991
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuro Sekiya, Kyuhachiro Iwasaki, Takashi Kimura, Tomoaki Nakano
  • Patent number: 4631553
    Abstract: An improved printer head for use in a non-impact type printer such as an ink-jet printer is provided. The printer head includes a first flow passage extending from an inlet port, to which ink under pressure is supplied, to a draining port and a second flow passage branching out of the first flow passage and leading to a nozzle aperture directed against a recording medium on which a desired character is to be printed. In the vicinity of the draining port is provided a draining vibrator to which an image or character signal is supplied. Depending on the operating condition of the draining vibrator, the ink is either drained out of the draining port or ejected out of the nozzle aperture. In the preferred mode, a driving vibrator is provided in the vicinity of the inlet port, and the driving vibrator is operated to deflect periodically inwardly to cause the ink to be normally discharged out of the nozzle aperture.
    Type: Grant
    Filed: April 8, 1985
    Date of Patent: December 23, 1986
    Assignee: Ricoh Company, Ltd.
    Inventor: Takuro Sekiya
  • Patent number: 4510509
    Abstract: A new nozzle structure is disclosed for an ink ejection head of an electric field on-demand type ink jet printer. A plurality of circular nozzles and first electrodes integral with the nozzles are arranged along the widthwise direction (X direction) and feed direction (Y direction) of a sheet of paper. A plurality of lead terminals are individually connected to the arrays of the first electrodes each of which extends in the Y direction. Second electrodes are located at the rear of the first electrodes and individually connected to the arrays of the first electrode each of which extends in the X direction. A third or counter electrode is positioned in front of the first electrodes and at the back of the sheet. Each of the second electrodes is mounted on a nozzle plate or a nozzle support.
    Type: Grant
    Filed: March 7, 1983
    Date of Patent: April 9, 1985
    Assignee: Ricoh Company, Ltd.
    Inventors: Masanori Horike, Tatsuya Furukawa, Takuro Sekiya, Yutaka Ebi, Takuro Isayama, Masaaki Tachiki