Patents by Inventor Takafumi Tsurumaru

Takafumi Tsurumaru 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: 8648517
    Abstract: A multilayer piezoelectric element includes a plurality of piezoelectric layers and a plurality of metal layers stacked alternately. The plurality of metal layers include a plurality of low-filled metal layers having a lower filling rate of metal composing the metal layers than oppositely disposed metal layers adjacent to each other in a stacking direction. The plurality of metal layers may include a plurality of thin metal layers having a smaller thickness than oppositely disposed metal layers adjacent to each other in a stacking direction. Where the plurality of metal layers are composed mainly of an alloy, the plurality of metal layers may include a plurality of high-ratio metal layers having a higher ratio of a component constituting the alloy than oppositely disposed metal layers adjacent to each other in a stacking direction.
    Type: Grant
    Filed: December 27, 2012
    Date of Patent: February 11, 2014
    Assignee: Kyocera Corporation
    Inventors: Takeshi Okamura, Masaki Terazono, Tomohiro Kawamoto, Takafumi Tsurumaru, Shigenobu Nakamura, Ken Yamamoto
  • Patent number: 8441174
    Abstract: In a multilayer piezoelectric element in which a plurality of piezoelectric layers and a plurality of metal layers are stacked alternately, the plurality of metal layers include a plurality of low-filled metal layers having a lower filling rate of metal composing the metal layers than oppositely disposed metal layers adjacent to each other in a stacking direction. In a multilayer piezoelectric element in which a plurality of piezoelectric layers and a plurality of metal layers are stacked alternately, the plurality of metal layers include a plurality of thin metal layers having a smaller thickness than oppositely disposed metal layers adjacent to each other in a stacking direction.
    Type: Grant
    Filed: June 15, 2006
    Date of Patent: May 14, 2013
    Assignee: Kyocera Corporation
    Inventors: Takeshi Okamura, Masaki Terazono, Tomohiro Kawamoto, Takafumi Tsurumaru, Shigenobu Nakamura, Ken Yamamoto
  • Patent number: 8288921
    Abstract: In a multilayer piezoelectric element comprising a plurality of piezoelectric layers and a plurality of metal layers which are alternately stacked one upon another, the metal layers includes a plurality of high resistance metal layers having a higher electrical resistance than adjacent metal layers on the both sides. The high resistance metal layers are regularly arranged so as to interpose a plurality of different metal layers other than the high resistance metal layers. In another multilayer piezoelectric element in which a plurality of piezoelectric layers and a plurality of metal layers are alternately stacked one upon another, at least one layer of the metal layers is formed by a plurality of partial metal layers disposed between the piezoelectric layers.
    Type: Grant
    Filed: September 29, 2006
    Date of Patent: October 16, 2012
    Assignee: Kyocera Corporation
    Inventors: Masaki Terazono, Takafumi Tsurumaru, Shigenobu Nakamura, Ken Yamamoto
  • Patent number: 8007903
    Abstract: A ceramic member in which the metal layers with high void ratio are sufficiently sintered to lower a residue of resin is produced. The method for manufacturing a ceramic member which comprises a step of forming a stacked compact from a plurality of metallic paste layers containing a metal component M1 that are stacked one on another via ceramic green sheets, and a step of firing the stacked compact, wherein at least one of plural metallic paste layers is formed as a second metallic paste layer that has the mass percentage X higher than that of the metallic paste layer that adjoin therewith in the stacking direction and a ceramic powder is contained in the second metallic paste layer in the step of forming the stacked compact, the mass percentage X being the proportion of the metal component M1 to the total metal content in the metallic paste layer.
    Type: Grant
    Filed: February 27, 2007
    Date of Patent: August 30, 2011
    Assignee: Kyocera Corporation
    Inventors: Takeshi Okamura, Shigenobu Nakamura, Tomohiro Kawamoto, Nobuyuki Ito, Takafumi Tsurumaru, Tsuyoshi Setoguchi
  • Patent number: 7786652
    Abstract: The multi-layer piezoelectric element comprises a stack having an active portion constituted from at least one piezoelectric layer and a plurality of internal electrodes consisting of first and second internal electrodes placed one on another, the active portion being subjected to expansion and contraction in response to a voltage applied across the first internal electrode and the second internal electrode, and external electrodes formed on two side faces of the stack with one thereof being connected to the first internal electrode and the other connected to the second internal electrode, wherein each of the external electrodes is constituted from three or more layers including a first layer formed in contact with the side face of the stack and a second layer formed on the first layer, to provide a multi-layer piezoelectric element having high durability.
    Type: Grant
    Filed: March 29, 2005
    Date of Patent: August 31, 2010
    Assignee: Kyocera Corporation
    Inventors: Shigenobu Nakamura, Takafumi Tsurumaru, Takeshi Okamura
  • Publication number: 20100032503
    Abstract: In a multilayer piezoelectric element comprising a plurality of piezoelectric layers and a plurality of metal layers which are alternately stacked one upon another, the metal layers includes a plurality of high resistance metal layers having a higher electrical resistance than adjacent metal layers on the both sides. The high resistance metal layers are regularly arranged so as to interpose a plurality of different metal layers other than the high resistance metal layers. In another multilayer piezoelectric element in which a plurality of piezoelectric layers and a plurality of metal layers are alternately stacked one upon another, at least one layer of the metal layers is formed by a plurality of partial metal layers disposed between the piezoelectric layers.
    Type: Application
    Filed: September 29, 2006
    Publication date: February 11, 2010
    Applicant: KYOCERA CORPORATION
    Inventors: Masaki Terazono, Takafumi Tsurumaru, Shigenobu Nakamura, Ken Yamamoto
  • Publication number: 20090295256
    Abstract: In a multilayer piezoelectric element in which a plurality of piezoelectric layers and a plurality of metal layers are stacked alternately, the plurality of metal layers include a plurality of low-filled metal layers having a lower filling rate of metal composing the metal layers than oppositely disposed metal layers adjacent to each other in a stacking direction. In a multilayer piezoelectric element in which a plurality of piezoelectric layers and a plurality of metal layers are stacked alternately, the plurality of metal layers include a plurality of thin metal layers having a smaller thickness than oppositely disposed metal layers adjacent to each other in a stacking direction.
    Type: Application
    Filed: June 15, 2006
    Publication date: December 3, 2009
    Applicant: KYOCERA CORPORATION
    Inventors: Takeshi Okamura, Masaki Terazono, Tomohiro Kawamoto, Takafumi Tsurumaru, Shigenobu Nakamura, Ken Yamamoto
  • Publication number: 20090220765
    Abstract: A ceramic member in which the metal layers with high void ratio are sufficiently sintered to lower a residue of resin is produced. The method for manufacturing a ceramic member which comprises a step of forming a stacked compact from a plurality of metallic paste layers containing a metal component M1 that are stacked one on another via ceramic green sheets, and a step of firing the stacked compact, wherein at least one of plural metallic paste layers is formed as a second metallic paste layer that has the mass percentage X higher than that of the metallic paste layer that adjoin therewith in the stacking direction and a ceramic powder is contained in the second metallic paste layer in the step of forming the stacked compact, the mass percentage X being the proportion of the metal component M1 to the total metal content in the metallic paste layer.
    Type: Application
    Filed: February 27, 2007
    Publication date: September 3, 2009
    Applicant: KYOCERA CORPORATION
    Inventors: Takeshi Okamura, Shigenobu Nakamura, Tomohiro Kawamoto, Nobuyuki Ito, Takafumi Tsurumaru, Tsuyoshi Setoguchi
  • Publication number: 20080238264
    Abstract: The multi-layer piezoelectric element comprises a stack having an active portion constituted from at least one piezoelectric layer and a plurality of internal electrodes consisting of first and second internal electrodes placed one on another, the active portion being subjected to expansion and contraction in response to a voltage applied across the first internal electrode and the second internal electrode, and external electrodes formed on two side faces of the stack with one thereof being connected to the first internal electrode and the other connected to the second internal electrode, wherein each of the external electrodes is constituted from three or more layers including a first layer formed in contact with the side face of the stack and a second layer formed on the first layer, to provide a multi-layer piezoelectric element having high durability.
    Type: Application
    Filed: March 29, 2005
    Publication date: October 2, 2008
    Applicant: Kyocera Corporation
    Inventors: Shigenobu Nakamura, Takafumi Tsurumaru, Takeshi Okamura
  • Patent number: 5350154
    Abstract: A ceramic valve assembly is housed in a recess formed in a metal pipe and is supported via gaskets by the metal pipes. Each gasket has a larger coefficient of linear expansion than that of the metal pipe. A clearance generated due to the thermal expansion difference between the metal pipe and the ceramic housing is absorbed by the large thermal expansion of the gasket so that no play is generated between the ceramic valve assembly and the metal pipe and the sealing force is maintained. Each gasket has beads constructed of spring material. An excessively large load does not act on the ceramic assembly because the beads are deformed to absorb the load.
    Type: Grant
    Filed: November 1, 1993
    Date of Patent: September 27, 1994
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Kenichiro Takama, Kimihide Horio, Michihiko Miyasaka, Takafumi Tsurumaru, Shinsuke Takenishi