Patents by Inventor Shinji Yasukawa

Shinji Yasukawa 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: 6907215
    Abstract: A carrier carries developer. A regulation member disposed at a lower portion of the carrier to control an amount of the developer carried by the carrier. A first container disposed below the carrier to contain the developer therein. A guiding path guides developer dropped by the regulation member from the carrier, to the first container.
    Type: Grant
    Filed: December 6, 2002
    Date of Patent: June 14, 2005
    Assignee: Seiko Epson Corporation
    Inventors: Shinji Yasukawa, Tomoe Aruga, Nobumasa Abe, Yujiro Nomura, Masanao Kunugi
  • Publication number: 20050095040
    Abstract: An electrostatic latent image is formed on an image carrier. A first roller is opposed to the image carrier with a gap in between. A second roller is in contact with the first roller such that toner of a one-component type is supplied onto the image carrier by way of the first roller to develop the electrostatic latent image as a visible toner image. A single power source supplies a bias voltage in which an AC voltage is superposed on a DC bias voltage. The bias voltage is supplied to the first roller through a first path and to the second roller through a second path. A resistor is provided on the first path between the first roller and a branching point of the first path and the second path.
    Type: Application
    Filed: September 30, 2004
    Publication date: May 5, 2005
    Inventors: Shinji Yasukawa, Nobuhiro Miyakawa, Hiroshi Toyama, Takeshi Kobayashi, Shoji Hiruta
  • Publication number: 20050084295
    Abstract: An image forming apparatus of the present invention comprises: a latent image carrier; and a developing means for charging a toner into a negative polarity by triboelectric charging, for converting an electrostatic latent image on said latent image carrier to a visible image with said toner and is characterized in that (1) the work function (?t) of said toner is set to be larger than the work function (?OPC) of the surface of said latent image carrier, or (2) in case that the apparatus is of a type transferring the visible image to an intermediate transfer medium, the apparatus is characterized in that the work function (?t) of said toner is set to be larger than the work function (?TM) of the surface of said intermediate transfer medium or (3) the work function (?OPC) of the surface of said latent image carrier, the work function (?t) of said toner, and the work function (?TM) of the surface of said intermediate transfer medium are set to satisfy a relation ?t>?OPC>?TM.
    Type: Application
    Filed: October 21, 2004
    Publication date: April 21, 2005
    Inventors: Nobuhiro Miyakawa, Shinji Yasukawa, Nobumasa Abe, Mikio Furumizu, Kaneo Yoda
  • Patent number: 6875550
    Abstract: A non-magnetic single-component toner 8 of the present invention has toner mother particles 8a, and external additives 12 comprising: two hydrophobic silicas 13, 14 of which particle diameters are different from each other, i.e. a mean primary particle diameter of 7 nm to 12 nm and a mean primary particle diameter of 40 nm to 50 nm, and a hydrophobic rutile/anatase type titanium oxide 15 having a spindle shape of which major axial diameter is in a range from 0.02 nm to 0.10 nm and the ratio of the major axial diameter to the minor axial diameter is set to be 2 to 8, wherein the external additives 12 adhere to the toner mother particles 8a. By the hydrophobic silicas 13, 14 having work function smaller than the work function of the toner mother particles 8a, the negative charging property is imparted to the toner mother particles 8a and the fluidity is also insured.
    Type: Grant
    Filed: July 10, 2002
    Date of Patent: April 5, 2005
    Assignee: Seiko Epson Corporation
    Inventors: Nobuhiro Miyakawa, Takuya Kadota, Hidehiro Takano, Shinji Yasukawa, Masanao Kunugi
  • Publication number: 20040265714
    Abstract: The invention provides an imaging system wherein toners of two or more colors are used to form toner images and the toner images are successively used to form a color image on a recording material. The imaging system can form an image with high transfer efficiency. An electrostatic latent image is formed on an image carrier. Using developing units for two or more colors, images are formed. Then, the images are successively transferred onto an intermediate transfer medium at a transfer voltage fed from a constant-voltage power supply. The developing units are located such that development occurs in descending toner work function order.
    Type: Application
    Filed: January 5, 2004
    Publication date: December 30, 2004
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Nobuhiro Miyakawa, Shinji Yasukawa, Mikio Furumizu, Nobumasa Abe, Masanao Kunugi, Yoshiro Koga
  • Patent number: 6829454
    Abstract: By causing the movement of charge from a toner to a latent image carrier, the amount of charge of the toner is lowered to an amount of charge suitable for facilitating the transfer of toner so as to improve the transfer efficiency. For this, an image forming apparatus includes a latent image carrier and a developing means for forming a negatively chargeable toner layer compose of two stories or less on a toner carrier by a toner layer thickness regulating member. An electrostatic latent image on the latent image carrier is developed with the toner to form a visible image and the visible image is transferred to a transfer medium. Further, the work functions (&PHgr;opc) of the surface of the latent image carrier is set to be larger than the work function (&PHgr;t) of the toner.
    Type: Grant
    Filed: August 21, 2002
    Date of Patent: December 7, 2004
    Assignee: Seiko Epson Corporation
    Inventors: Nobuhiro Miyakawa, Shinji Yasukawa, Nobumasa Abe, Mikio Furumizu
  • Publication number: 20040234881
    Abstract: A non-magnetic single-component toner 8 of the present invention has toner mother particles 8a, and external additives 12 comprising: two hydrophobic silicas 13, 14 of which particle diameters are different from each other, i.e. a mean primary particle diameter of 7 nm to 12 nm and a mean primary particle diameter of 40 nm to 50 nm, and a hydrophobic rutile/anatase type titanium oxide 15 having a spindle shape of which major axial diameter is in a range from 0.02 nm to 0.10 nm and the ratio of the major axial diameter to the minor axial diameter is set to be 2 to 8, wherein the external additives 12 adhere to the toner mother particles 8a. By the hydrophobic silicas 13, 14 having work function smaller than the work function of the toner mother particles 8a, the negative charging property is imparted to the toner mother particles 8a and the fluidity is also insured.
    Type: Application
    Filed: May 13, 2004
    Publication date: November 25, 2004
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Nobuhiro Miyakawa, Takuya Kadota, Hidehiro Takano, Shinji Yasukawa, Masanao Kunugi
  • Patent number: 6819899
    Abstract: An image forming apparatus including a latent image carrier and a developing device for charging a toner into a negative polarity by triboelectric charging, wherein the work function of the toner is set to be larger than the work function of the surface of the latent image carrier. When the apparatus includes an intermediate transfer medium, the work function of the toner is set to be larger than the work function of the surface of the intermediate transfer medium. In another embodiment, the work function &PHgr;opc of the surface of the latent image carrier, the work function &PHgr;t of the toner, and the work function &PHgr;TM of the surface of the intermediate transfer medium are set to satisfy a relationship &PHgr;t>&PHgr;OPC>&PHgr;TM. These relationships help to reduce fog, and improve transfer efficiency which reduces the consumption of the toner.
    Type: Grant
    Filed: June 24, 2002
    Date of Patent: November 16, 2004
    Assignee: Seiko Epson Corporation
    Inventors: Nobuhiro Miyakawa, Shinji Yasukawa, Nobumasa Abe, Mikio Furumizu, Kaneo Yoda
  • Patent number: 6729002
    Abstract: A pressurizing chamber 1 is formed as a recess by half etching of a silicon single-crystal substrate 2. A nozzle communicating hole 6 through which the pressurizing chamber 1 is connected to a nozzle opening 5 is formed as a through hole which is smaller in width than the pressurizing chamber 1. The pressurizing chamber 1 is connected to the nozzle opening 5 in the other face via the nozzle communicating hole 6 while reducing the volume of the pressurizing chamber 1 to a degree as small as possible. The silicon single-crystal substrate is used as a member constituting a spacer so that an ink drop of a reduced ink amount suitable for high density printing flies with high positioning accuracy.
    Type: Grant
    Filed: May 23, 2000
    Date of Patent: May 4, 2004
    Assignee: Seiko Epson Corporation
    Inventors: Shinji Yasukawa, Minoru Usui, Takahiro Naka, Tsuyoshi Kitahara, Noriaki Okazawa, Hideaki Sonehara
  • Publication number: 20030193549
    Abstract: A pressurizing chamber 1 is formed as a recess by half etching of a silicon single-crystal substrate 2. A nozzle communicating hole 6 through which the pressurizing chamber 1 is connected to a nozzle opening 5 is formed as a through hole which is smaller in width than the pressurizing chamber 1. The pressurizing chamber 1 is connected to the nozzle opening 5 in the other face via the nozzle communicating hole 6 while reducing the volume of the pressurizing chamber 1 to a degree as small as possible. The silicon single-crystal substrate is used as a member constituting a spacer so that an ink drop of a reduced ink amount suitable for high density printing flies with high positioning accuracy.
    Type: Application
    Filed: April 30, 2003
    Publication date: October 16, 2003
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Shinji Yasukawa, Minoru Usui, Takahiro Naka, Tsuyoshi Kitahara, Noriaki Okazawa, Hideaki Sonehara
  • Publication number: 20030174107
    Abstract: The present invention realizes proper driving circuits in a driving-circuit integral type liquid crystal display device which has an increased screen size. The liquid crystal display device includes a liquid crystal display panel and a driving circuit which supplies video signals to video signal lines formed on the liquid crystal display panel. The driving circuit is comprised of a first driving circuit which is formed in a step similar to a step for forming pixels provided to the liquid crystal display panel and a second driving circuit which is connected to the liquid crystal display panel after formation of the liquid crystal display panel. The first driving circuit is constituted of a switching circuit which is capable of distributing an output of the second driving circuit to a plurality of video signal lines.
    Type: Application
    Filed: February 7, 2003
    Publication date: September 18, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Hiroshi Watanabe, Shinji Yasukawa, Hidetoshi Kida, Yoshihisa Ooishi
  • Publication number: 20030157419
    Abstract: A non-magnetic single-component toner 8 of the present invention has toner mother particles 8a, and external additives 12 comprising: two hydrophobic silicas 13, 14 of which particle diameters are different from each other, i.e. a mean primary particle diameter of 7 nm to 12 nm and a mean primary particle diameter of 40 nm to 50 nm, and a hydrophobic rutile/anatase type titanium oxide 15 having a spindle shape of which major axial diameter is in a range from 0.02 nm to 0.10 nm and the ratio of the major axial diameter to the minor axial diameter is set to be 2 to 8, wherein the external additives 12 adhere to the toner mother particles 8a. By the hydrophobic silicas 13, 14 having work function smaller than the work function of the toner mother particles 8a, the negative charging property is imparted to the toner mother particles 8a and the fluidity is also insured.
    Type: Application
    Filed: July 10, 2002
    Publication date: August 21, 2003
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Nobuhiro Miyakawa, Takuya Kadota, Hidehiro Takano, Shinji Yasukawa, Masanao Kunugi
  • Publication number: 20030113139
    Abstract: A carrier carries developer. A regulation member disposed at a lower portion of the carrier to control an amount of the developer carried by the carrier. A first container disposed below the carrier to contain the developer therein. A guiding path guides developer dropped by the regulation member from the carrier, to the first container.
    Type: Application
    Filed: December 6, 2002
    Publication date: June 19, 2003
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Shinji Yasukawa, Tomoe Aruga, Nobumasa Abe, Yujiro Nomura, Masanao Kunugi
  • Publication number: 20030095814
    Abstract: An image forming apparatus of the present invention comprises: a latent image carrier; and a developing means for charging a toner into a negative polarity by triboelectric charging, for converting an electrostatic latent image on said latent image carrier to a visible image with said toner and is characterized in that (1) the work function (&PHgr;t) of said toner is set to be larger than the work function (&PHgr;OPC) of the surface of said latent image carrier, or (2) in case that the apparatus is of a type transferring the visible image to an intermediate transfer medium, the apparatus is characterized in that the work function (&PHgr;t) of said toner is set to be larger than the work function (&PHgr;TM) of the surface of said intermediate transfer medium or (3) the work function (&PHgr;OPC) of the surface of said latent image carrier, the work function (&PHgr;t) of said toner, and the work function (&PHgr;TM) of the surface of said intermediate transfer medium are set to satisfy a relation &PHgr;t>&PHgr
    Type: Application
    Filed: June 24, 2002
    Publication date: May 22, 2003
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Nobuhiro Miyakawa, Shinji Yasukawa, Nobumasa Abe, Mikio Furumizu, Kaneo Yoda
  • Patent number: 6556182
    Abstract: A liquid crystal display element having pixels, video signal lines applying a video signal voltage to the pixels and a video signal line driver supplying the video signal voltages to the video signal lines. The video signal line driver circuit includes a gray-scale voltage generating circuit provided with a resistor circuit dividing voltages between plural gray-scale reference voltages to generate plural gray-scale voltages, and selector circuits selecting one gray-scale voltage in accordance with the display data. The resistor circuit includes a resistive element provided with plural Intermediate taps for dividing voltages to generate the gray-scale voltages, gray-scale voltage lines corresponding to the gray-scale voltages, an interlayer insulating film insulating the gray-scale lines from the resistive element, and connections connecting the gray-scale voltage lines to corresponding ones of the intermediate taps through a hole in the interlayer insulating film.
    Type: Grant
    Filed: August 24, 2000
    Date of Patent: April 29, 2003
    Assignees: Hitachi, Ltd., Hitachi Device Engineering Co., Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Mitsuru Goto, Yozo Nakayasu, Shinji Yasukawa, Kentaro Agata, Yuji Yamashita, Koichi Kotera
  • Publication number: 20030053821
    Abstract: By causing the movement of charge from a toner to a latent image carrier, the amount of charge of the toner is lowered to an amount of charge suitable for facilitating the transfer of toner so as to improve the transfer efficiency. For this, an image forming apparatus comprises a latent image carrier 1 and a developing means 4 for forming a negatively chargeable toner layer composed of two stories or less on a toner carrier 10 by a toner layer thickness regulating member 9, wherein an electrostatic latent image on the latent image carrier is developed with the toner to form a visible image and the visible image is transferred to a transfer medium 5, and is characterized in that the work function (&PHgr;opc) of the surface of the latent image carrier is set to be larger than the work function (&PHgr;t) of the toner.
    Type: Application
    Filed: August 21, 2002
    Publication date: March 20, 2003
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Nobuhiro Miyakawa, Shinji Yasukawa, Nobumasa Abe, Mikio Furumizu
  • Patent number: 6535189
    Abstract: A liquid crystal display device includes a liquid crystal panel having plural pixels and a video signal line driver circuit for supplying a video signal voltage to each of the pixels via a corresponding one of plural video lines in accordance with a P-bit display data.
    Type: Grant
    Filed: July 21, 2000
    Date of Patent: March 18, 2003
    Assignees: Hitachi ULSI Systems Co., Ltd., Hitachi Device Engineering Co., Ltd., Hitachi, Ltd.
    Inventors: Kenichi Akiyama, Yuji Yamashita, Hironobu Isami, Mitsuru Goto, Shinji Yasukawa, Koichi Kotera
  • Publication number: 20020180684
    Abstract: The present invention realizes a liquid crystal display which mounts driving circuits of low power consumption on a substrate on which a display part is mounted. The driving circuits which supply gray scale voltages to pixels are mounted on a liquid crystal display panel. Display data is transferred between the driving circuits using wiring formed on the liquid crystal display panel, the display data is transferred in the inside of the driving circuits through inner data bus lines, and a data inversion calculation which inverts values of the display data is performed in the inside of the driving circuits for achieving the low power consumption.
    Type: Application
    Filed: April 19, 2002
    Publication date: December 5, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Kazunari Saitou, Shigeru Itou, Yukihide Ode, Youzou Nakayasu, Shinji Yasukawa
  • Patent number: 6460981
    Abstract: A pressurizing chamber 1 is formed as a recess by half etching of a silicon single-crystal substrate 2. A nozzle communicating hole 6 through which the pressurizing chamber 1 is connected to a nozzle opening 5 is formed as a through hole which is smaller in width than the pressurizing chamber 1. The pressurizing chamber 1 is connected to the nozzle opening 5 in the other face via the nozzle communicating hole 6 while reducing the volume of the pressurizing chamber 1 to a degree as small as possible. The silicon single-crystal substrate is used as a member constituting a spacer so that an ink drop of a reduced ink amount suitable for high density printing flies with high positioning accuracy.
    Type: Grant
    Filed: April 20, 2000
    Date of Patent: October 8, 2002
    Inventors: Shinji Yasukawa, Minoru Usui, Takahiro Naka, Tsuyoshi Kitahara, Noriaki Okazawa, Hideaki Sonehara
  • Publication number: 20020140782
    Abstract: A pressurizing chamber 1 is formed as a recess by half etching of a silicon single-crystal substrate 2. A nozzle communicating hole 6 through which the pressurizing chamber 1 is connected to a nozzle opening 5 is formed as a through hole which is smaller in width than the pressurizing chamber 1. The pressurizing chamber 1 is connected to the nozzle opening 5 in the other face via the nozzle communicating hole 6 while reducing the volume of the pressurizing chamber 1 to a degree as small as possible. The silicon single-crystal substrate is used as a member constituting a spacer so that an ink drop of a reduced ink amount suitable for high density printing flies with high positioning accuracy.
    Type: Application
    Filed: March 22, 2002
    Publication date: October 3, 2002
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Shinji Yasukawa, Minoru Usui, Takahiro Naka, Tsuyoshi Kitahara, Noriaki Okazawa, Hideaki Sonehara