Patents by Inventor Tadaaki Hagata

Tadaaki Hagata 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: 6410107
    Abstract: Methods for manufacturing an electrostatic actuator that comprises electrode members having opposing surfaces with a gap disposed therebetween. In an ink jet head, a bottom surface of a diaphragm may be one of the electrodes (common electrode) of an eletrostatic actuator, the diaphragm forming a wall of an ink chamber in the ink jet head that is displaced relatively by an electrostatic force. A hydrophobic film, preferably hexamethyldisilazane (HMDS), is formed on at least one of the opposing electrode surfaces to improve the durability of the electrostatic actuator so that electrostatic attraction between opposing electrode members does not decrease and the opposing electrode members do not stick together. HMDS molecules are smaller than PFDA molecules, and a uniform, variation-free hydrophobic film can therefore be formed even when the gap between opposing electrodes is narrow. Durability and film stability of a HMDS hydrophobic film are also high.
    Type: Grant
    Filed: November 30, 2000
    Date of Patent: June 25, 2002
    Assignee: Seiko Epson Corporation
    Inventors: Kazuhiko Sato, Hiroyuki Maruyama, Masahiro Fujii, Tadaaki Hagata, Koji Kitahara, Keiichi Mukaiyama
  • Publication number: 20010000329
    Abstract: An electrostatic actuator comprising opposing electrode members displaced relatively by an electrostatic force is provided with improved durability so that electrostatic attraction between opposing members does not drop and the opposing electrode members do not stick together. Hydrophobic films of hexamethyldisilazane (HMDS) are formed on a surface of segment electrode and a bottom surface of a diaphragm (common electrode) of an eletrostatic actuator wherein the diaphragm forms a wall of an ink chamber in an ink jet head. HMDS molecules are smaller than PFDA molecules, and a uniform, variation-free hydrophobic film can therefore be formed even when the gap between opposing electrodes is narrow. Durability and film stability of a HMDS hydrophobic film are also high. An electrostatic actuator with high durability and operating stability can thus be achieved.
    Type: Application
    Filed: November 30, 2000
    Publication date: April 19, 2001
    Inventors: Kazuhiko Sato, Hiroyuki Maruyama, Masahiro Fujii, Tadaaki Hagata, Koji Kitahara, Keiichi Mukaiyama
  • Patent number: 6213590
    Abstract: A high reliability ink jet head for an ink jet recording apparatus enabling consistent ink ejecting with no nozzle clogging. The ink jet head therefor comprises a substrate comprising plural ink passages, each comprising a nozzle, pressure generator continuous to the nozzle, and an orifice, and an ink supply member common to the plural ink passages. The substrate comprising an anisotropic crystalline material such as silicon, and a filter channel formed integrally to the ink supply member by anisotropic etching.
    Type: Grant
    Filed: September 8, 1999
    Date of Patent: April 10, 2001
    Assignee: Seiko Epson Corporation
    Inventors: Masahiro Fujii, Keiichi Mukaiyama, Hiroyuki Maruyama, Tadaaki Hagata, Ikuhiro Miyashita
  • Patent number: 6190003
    Abstract: An electrostatic actuator comprising opposing electrode members displaced relatively by an electrostatic force is provided with improved durability so that electrostatic attraction between opposing members does not drop and the opposing electrode members do not stick together. Hydrophobic films of hexamethyldisilazane (HMDS) are formed on a surface of segment electrode and a bottom surface of a diaphragm (common electrode) of an eletrostatic actuator wherein the diaphragm forms a wall of an ink chamber in an ink jet head. HMDS molecules are smaller than PFDA molecules, and a uniform, variation-free hydrophobic film can therefore be formed even when the gap between opposing electrodes is narrow. Durability and film stability of a HMDS hydrophobic film are also high. An electrostatic actuator with high durability and operating stability can thus be achieved.
    Type: Grant
    Filed: December 19, 1997
    Date of Patent: February 20, 2001
    Assignee: Seiko Epson Corporation
    Inventors: Kazuhiko Sato, Hiroyuki Maruyama, Masahiro Fujii, Tadaaki Hagata, Koji Kitahara, Keiichi Mukaiyama
  • Patent number: 6164759
    Abstract: A manufacturing method for a device having an electrostatic actuator for example inkjet head, whereby warping of the diaphragms does not occur as a result of anodic bonding is provided. The method comprises the steps of etching a first substrate on the first surface thereof to form a concave portion and a diaphragm provided in bottom walls of the concave portion, forming an electrode on a second substrate, and anodically bonding the second substrate to a second surface of the first substrate, opposite the first surface, such that the electrode is aligned adjacent to the diaphragm with a gap therebetween. The bonding temperature of the anodically bonding step is set within a temperature range whereby the contraction of the first substrate after bonding is equal to or greater than the contraction of the second substrate.
    Type: Grant
    Filed: August 5, 1999
    Date of Patent: December 26, 2000
    Assignee: Seiko Epson Corporation
    Inventors: Masahiro Fujii, Keiichi Mukaiyama, Hiroyuki Maruyama, Tadaaki Hagata, Yoshio Maeda, Hiroshi Komatsu, Mitsuro Atobe
  • Patent number: 5992978
    Abstract: A high reliability ink jet head for an ink jet recording apparatus enabling consistent ink ejecting with no nozzle clogging. The ink jet head therefor comprises a substrate comprising plural ink passages, each comprising a nozzle, pressure generator continuous to the nozzle, and an orifice, and an ink supply member common to the plural ink passages. The substrate comprising an anisotropic crystalline material such as silicon, and a filter channel formed integrally to the ink supply member by anisotropic etching.
    Type: Grant
    Filed: April 19, 1995
    Date of Patent: November 30, 1999
    Assignee: Seiko Epson Corporation
    Inventors: Masahiro Fujii, Keiichi Mukaiyama, Hiroyuki Maruyama, Tadaaki Hagata, Ikuhiro Miyashita
  • Patent number: 5912684
    Abstract: An inkjet head comprising a nozzle, an ink passage in communication with the nozzle, a diaphragm provided at one part of the ink passage, and an electrode provided in opposition to the diaphragm whereby an electrical pulse is applied between the diaphragm and electrode to deform the diaphragm by means of electrostatic force, thereby ejecting ink droplets from the nozzle. The actuator contains at least a vibration chamber formed by the diaphragm and electrode, and is sealed or made airtight with the volume V so that the ratio between the actuator volume V and the volume .DELTA.V eliminated by a distortion of the diaphragm during ink-jet head drive is within the range 2.ltoreq.V/.DELTA.V.ltoreq.8.
    Type: Grant
    Filed: February 3, 1997
    Date of Patent: June 15, 1999
    Assignee: Seiko Epson Corporation
    Inventors: Masahiro Fujii, Keiichi Mukaiyama, Hiroyuki Maruyama, Tadaaki Hagata, Mitsuro Atobe, Shinichi Kamisuki, Shinichi Yotsuya, Hiroshi Koeda, Yoshihiro Ohno, Hitoshi Tanbo
  • Patent number: 5489967
    Abstract: In a magnetic printing apparatus wherein a demagnetizer 2 as a latent image eraser, a magnetic head 3 constituting a latent image former, a developer 4, a transfer roller 5, a fixer 6, and a cleaner 7 are disposed in this order around a latent image carrier 1, a recording paper 15 including a stack of plural sheets of carbonless paper is fed, transported, and discharged, a single-component dry toner 8 is used, and pressure transfer is made by a transfer roller 5 at a load per unit roller length of 5 kgf/cm or more, thereby achieving printing and copying.
    Type: Grant
    Filed: November 10, 1993
    Date of Patent: February 6, 1996
    Assignee: Seiko Epson Corporation
    Inventors: Yusuke Sakagami, Kunihiro Inoue, Tadashi Shimizu, Tetsushi Takahashi, Tadaaki Hagata, Kazuhiko Sato