Patents by Inventor Tsutomu Nishiwaki

Tsutomu Nishiwaki 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: 20020094372
    Abstract: A piezoelectric element having a piezoelectric film where the difference in the quantity of lead along the thickness of the film is minimized. The film is obtained by first applying, at least once, a first sol for use in forming a PZT film on a substrate having a lower electrode formed thereon. Second, applying a second sol having the greater lead content than the first sol. Third, subjecting these films to heat treatment at a predetermined temperature at least once. The second sol has a composition capable of forming a piezoelectric film having a Perovskite structure expressed generally by AxByO3, and the content of material constituting the A site of the first sol is greater than what constitutes the A site of the second sol.
    Type: Application
    Filed: November 30, 1999
    Publication date: July 18, 2002
    Inventors: HONG QIU, SOICHI MORIYA, HIROYUKI KAMEI, KOJI SUMI, MASAMI MURAI, TSUTOMU NISHIWAKI
  • Patent number: 6419848
    Abstract: A piezoelectric actuator, comprising a stacked structure consisting of a top electrode 5, a piezoelectric film 4, and a bottom electrode 3, wherein the piezoelectric film comprises a first group 42 of piezoelectric ceramic particles and a second group 43 of piezoelectric ceramic particles. A distinctive feature is that the particles constituting the first group of piezoelectric ceramic particles are larger than the jingo particles constituting the second group of piezoelectric ceramic particles, and the first group of piezoelectric ceramic particles and the second group of piezoelectric ceramic particles have mutually different compositions. The piezoelectric actuator can thus be manufactured by an application method in a low-temperature environment, and a thicker piezoelectric film can be obtained. In addition, a highly practical piezoelectric film can be provided by combining the advantages of a plurality of material types.
    Type: Grant
    Filed: March 2, 2000
    Date of Patent: July 16, 2002
    Assignee: Seiko Epson Corporation
    Inventors: Hong Qiu, Koji Sumi, Tsutomu Nishiwaki, Haruo Nakamura
  • Patent number: 6419849
    Abstract: When a piezoelectric material is manufactured by hydrothermal method, the proper amount of lead contained in the piezoelectric film can be ensured and decreases in piezoelectric characteristics can be prevented. A method for manufacturing a piezoelectric material expressed by the formula ABO3, containing an element “a” as the element expressed by A above, and having a perovskite crystal structure, comprises a first step of producing an oxide containing an element “a′”, and a second step of producing a piezoelectric material by subjecting the oxide produced in the first step to a hydrothermal processing using an aqueous solution containing the element “a”, wherein the amount of the element “a” contained in the piezoelectric material produced in the second step is increased over the amount of the element “a” contained in the oxide produced in the first step.
    Type: Grant
    Filed: March 27, 2000
    Date of Patent: July 16, 2002
    Assignee: Seiko Epson Corporation
    Inventors: Hong Qiu, Koji Sumi, Tsutomu Nishiwaki, Masanori Okuyama, Zhiqiang Wei
  • Publication number: 20020071969
    Abstract: When a piezoelectric material is manufactured by hydrothermal method, the proper amount of lead contained in the piezoelectric film can be ensured and decreases in piezoelectric characteristics can be prevented. A method for manufacturing a piezoelectric material expressed by the formula ABO3, containing an element “a” as the element expressed by A above, and having a perovskite crystal structure, comprises a first step of producing an oxide containing an element “a′”, and a second step of producing a piezoelectric material by subjecting the oxide produced in the first step to a hydrothermal processing using an aqueous solution containing the element “a”, wherein the amount of the element “a”, contained in the piezoelectric material produced in the second step is increased over the amount of the element “a” contained in the oxide produced in the first step.
    Type: Application
    Filed: January 18, 2002
    Publication date: June 13, 2002
    Inventors: Hong Qiu, Koji Sumi, Tsutomu Nishiwaki, Masanori Okuyama, Zhiqiang Wei
  • Patent number: 6402304
    Abstract: A piezoelectric actuator, made of a substrate and a piezoelectric film layer resistant to erosion is provided. The area of the piezoelectric actuator can be enlarged, and has a flat top surface. The present invention further provides an ink jet printing head, a printer, a method for manufacturing a piezoelectric actuator, and a method for manufacturing an ink jet printing head. The piezoelectric actuator includes a piezoelectric film disposed between a lower electrode and an upper electrode. Columnar crystal grains of piezoelectric ceramic which compose the piezoelectric actuator are random-oriented in a film thickness direction, and have a mean diameter in the range of 100 nm to 15,000 nm. The method for manufacturing the actuator includes the step of forming precursor films, which are composed of metal and oxygen, over a lower electrode, providing a hydrothermal treatment by dipping the precursor films in an alkaline solution, which as 2 M[mol/l] or less, more preferably 0.
    Type: Grant
    Filed: August 12, 1999
    Date of Patent: June 11, 2002
    Assignee: Seiko Epson Corporation
    Inventors: Hong Qiu, Koji Sumi, Masato Shimada, Tsutomu Nishiwaki, Masanori Okuyama, Zhi Quiang Wei
  • Patent number: 6378996
    Abstract: Disclosed are an ink-jet recording head in which rigidity of a compartment wall is improved and pressure generating chambers are arranged in a high density, a manufacturing method and an ink-jet recording apparatus thereof. An ink-jet recording head includes: a passage-forming substrate 10 having at least silicon layer that consists of single crystal silicon and pressure generating chambers 12 defined thereon, which communicate with a nozzle orifice 21; and a piezoelectric element 300 for generating a pressure change in the pressure generating chamber 12, the piezoelectric element 300 being provided in a region opposite the pressure generating chamber 12 via a vibration plate, which constitutes a portion of the pressure generating chamber 12. The ink-jet recording head further includes a joining plate 20 joined to the passage-forming substrate 10 on the surface where the piezoelectric element 300 is formed, and the nozzle orifice 21 is provided on the joining plate 20.
    Type: Grant
    Filed: November 15, 2000
    Date of Patent: April 30, 2002
    Assignee: Seiko Epson Corporation
    Inventors: Masato Shimada, Akira Matsuzawa, Yoshinao Miyata, Tsutomu Nishiwaki
  • Publication number: 20020018105
    Abstract: A process for producing a laminated ink-jet recording head including the steps of forming a titanium layer across a surface of a diaphragm, and forming a layer of a piezoelectric material on the titanium layer by a hydrothermal method.
    Type: Application
    Filed: October 11, 2001
    Publication date: February 14, 2002
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Minoru Usui, Masato Shimada, Masami Murai, Kouji Sumi, Tsutomu Nishiwaki
  • Publication number: 20010054857
    Abstract: Provided is a luminous element which utilizes a tribo-luminescence phenomenon.
    Type: Application
    Filed: July 30, 2001
    Publication date: December 27, 2001
    Applicant: Seiko Epson Corporation
    Inventors: Hong Qiu, Koji Sumi, Tsutomu Nishiwaki
  • Patent number: 6332672
    Abstract: An ink jet recording head comprises: a passage form substrate having, a diaphragm forming a part of a pressure generating chamber communicating with a nozzle aperture and at least the upper surface of which acts as a lower electrode, and a piezoelectric vibrator including a piezoelectric material layer formed on the surface of the diaphragm, an upper electrode formed on the surface of the piezoelectric material layer and a piezoelectric active part formed in an area opposite to the pressure generating chamber; a cap member joined to the side of the piezoelectric material layer of the passage formed substrate for sealing space in a state in which space to extent that a movement is not prevented is secured; and a flexible portion for absorbing the change of pressure in the space of the cap member.
    Type: Grant
    Filed: April 30, 1998
    Date of Patent: December 25, 2001
    Assignee: Seiko Epson Corporation
    Inventors: Shiro Yazaki, Shinri Sakai, Tsutomu Nishiwaki
  • Patent number: 6332254
    Abstract: A process for producing a laminated ink-jet recording head including the steps of forming a titanium layer across a surface of a diaphragm, and forming a layer of a piezoelectric material on the titanium layer by a hydrothermal method.
    Type: Grant
    Filed: April 6, 1999
    Date of Patent: December 25, 2001
    Assignee: Seiko Epson Corporation
    Inventors: Minoru Usui, Masato Shimada, Masami Murai, Kouji Sumi, Tsutomu Nishiwaki
  • Patent number: 6284434
    Abstract: A piezoelectric thin film element is provided that functions well as an actuator, that yields the desired composition, and that exhibits good piezoelectric thin film distortion characteristics. A lower electrode is formed on a substrate, a piezoelectric thin film precursor thin film layer is formed on the lower electrode, this is subjected to patterning, and a heating solution is applied to the substrate to implement hydrothermal processing, thereby selectively crystallizing the precursor thin film layer and yielding a piezoelectric thin film layer.
    Type: Grant
    Filed: October 20, 1998
    Date of Patent: September 4, 2001
    Assignee: Seiko Epson Corporation
    Inventors: Hiroyuki Kamei, Tsutomu Nishiwaki, Makoto Matsuzaki, Masato Shimada, Akira Matsuzawa
  • Patent number: 6281617
    Abstract: Provided is a luminous element which utilizes a tribo-luminescence phenomenon. The luminous element comprises: a pressure luminous layer (14) which emits light upon the application of pressure; and a piezoelectric element which comprises a piezoelectric film (12) held between electrode films (11) and (13), and which is located so as to be capable of applying pressure on the pressure luminous layer.
    Type: Grant
    Filed: December 10, 1999
    Date of Patent: August 28, 2001
    Assignee: Seiko Epson Corporation
    Inventors: Hong Qiu, Koji Sumi, Tsutomu Nishiwaki
  • Patent number: 6250753
    Abstract: To suppress an increase in the pressure of an ink reservoir caused by the ink reversely flowed from an ink cavity without causing a lead wire to be damaged or to get fatigued. A thin portion 13 which becomes resiliently deformed by the ink reversely flowed from an ink cavity 2 is provided in the area of a compliance plate facing an ink reservoir 4.
    Type: Grant
    Filed: January 19, 1999
    Date of Patent: June 26, 2001
    Assignee: Seiko Epson Corporation
    Inventors: Tsutomu Nishiwaki, Yoshinao Miyata
  • Patent number: 6193360
    Abstract: To suppress an increase in the pressure of an ink reservoir caused by the ink reversely flowed from an ink cavity without causing a lead wire to be damaged or to get fatigued. A thin portion 13 which becomes resiliently deformed by the ink reversely flowed from an ink cavity 2 is provided in the area of a compliance plate facing an ink reservoir 4.
    Type: Grant
    Filed: January 24, 1997
    Date of Patent: February 27, 2001
    Assignee: Seiko Epson Corporation
    Inventors: Tsutomu Nishiwaki, Yoshinao Miyata
  • Patent number: 6158847
    Abstract: A laminated ink-jet recording head is provided that has a strong joint between the diaphragm and the piezoelectric vibrating element and which can be driven on low voltage. The recording head is of such a design that a lower electrode is provided on the diaphragm in at lest a region that corresponds to said pressure generating chamber, the lower electrode being overlaid with the piezoelectric vibrating element formed by a hydrothermal method, said piezoelectric vibrating element in turn being overlaid with an upper electrode and having a film thickness of not less than 1 .mu.m but not more than 10 .mu.m. The invention further provides a process for producing this recording head, as well as an apparatus such as a printer that is equipped with this recording head.
    Type: Grant
    Filed: May 14, 1997
    Date of Patent: December 12, 2000
    Assignee: Seiko Epson Corporation
    Inventors: Minoru Usui, Masato Shimada, Masami Murai, Kouji Sumi, Tsutomu Nishiwaki
  • Patent number: 6147438
    Abstract: The present invention provides a piezoelectric film element with improved adhesion between a first protective film and a substrate. This invention also provides a method of manufacturing a piezoelectric film element, which makes it possible to selectively form, by a hydrothermal synthesis, a piezoelectric film with excellent piezoelectric properties in a specified area. This piezoelectric element comprises, over a substrate 12: a piezoelectric film; a common electrode and an individual electrode located to hold the piezoelectric film in between; a first protective film 14 which is formed over almost the entire surface of the substrate 12 and which protects the substrate 12 to avoid the formation of the piezoelectric film directly over the substrate 12; and a base film 16 which is formed over the first protective film 14 in the area for forming the piezoelectric film, and which functions as a base when the piezoelectric film is caused to grow to be formed.
    Type: Grant
    Filed: June 22, 1998
    Date of Patent: November 14, 2000
    Assignees: Seiko Epson Corporation, Ube Industries, Ltd.
    Inventors: Tsutomu Nishiwaki, Masami Murai, Kazuo Hashimoto, Toshihiko Anno
  • Patent number: 6126279
    Abstract: An ink-jet printing head comprises: a pressurizing chamber substrate having first and second sides opposing each other; a plurality of pressurizing chambers formed on the first side of the pressurizing chamber substrate; channels formed on the second side of the pressuring chamber substrate to be opposite to the pressuring chambers, respectively; oscillating plate films for pressurizing ink within the respective pressurizing chambers; and piezoelectric thin-film elements, each having upper and lower electrodes and a piezoelectric film sandwiched between the upper and lower electrodes, the piezoelectric thin-film being formed in the channel, wherein at least the upper electrode is formed to have a narrower width than that of the pressurizing chamber. And a method for producing the ink-jet head.
    Type: Grant
    Filed: June 30, 1998
    Date of Patent: October 3, 2000
    Assignee: Seiko Epson Corporation
    Inventors: Masato Shimada, Tetsushi Takahashi, Tsutomu Nishiwaki, Tsutomu Hashizume
  • Patent number: 6103072
    Abstract: A piezoelectric thin-film device includes: a substrate; and a piezoelectric thin film formed on the substrate, wherein a thickness of the piezoelectric thin film is 1 to 10 .mu.m, a crystal grain size of the piezoelectric thin film is 0.05 to 1 .mu.m, and a surface roughness (Rmax) of the piezoelectric thin film is no more than 1 .mu.m.
    Type: Grant
    Filed: February 24, 1998
    Date of Patent: August 15, 2000
    Assignee: Seiko Epson Corporation
    Inventors: Tsutomu Nishiwaki, Kouji Sumi, Masami Murai, Masato Shimada
  • Patent number: 6051914
    Abstract: A piezoelectric device comprises: a lower electrode; a piezoelectric film formed on the lower electrode; and an upper electrode formed on the piezoelectric film, wherein a low dielectric material having a dielectric constant that is lower than the piezoelectric film is formed at grain boundary exposed regions of the piezoelectric film.
    Type: Grant
    Filed: February 4, 1998
    Date of Patent: April 18, 2000
    Assignee: Seiko Epson Corporation
    Inventor: Tsutomu Nishiwaki
  • Patent number: 6019458
    Abstract: An ink-jet printing head comprises: a pressurizing chamber substrate having first and second sides opposing each other; a plurality of pressurizing chambers formed on the first side of the pressurizing chamber substrate; channels formed on the second side of the pressuring chamber substrate to be opposite to the pressuring chambers, respectively; oscillating plate films for pressurizing ink within the respective pressurizing chambers; and piezoelectric thin-film elements, each having upper and lower electrodes and a piezoelectric film sandwiched between the upper and lower electrodes, the piezoelectric thin-film being formed in the channel, wherein at least the upper electrode is formed to have a narrower width than that of the pressurizing chamber. And a method for producing the ink-jet head.
    Type: Grant
    Filed: November 25, 1996
    Date of Patent: February 1, 2000
    Assignee: Seiko Epson Corporation
    Inventors: Masato Shimada, Tetsushi Takahashi, Tsutomu Nishiwaki, Tsutomu Hashizume