Patents by Inventor Koji Sumi

Koji Sumi 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: 20170036446
    Abstract: A liquid ejection head includes a substrate in which a pressure generating chamber that communicates with a nozzle opening is formed; and a piezoelectric element having a piezoelectric layer, a first electrode that is formed on a surface of the piezoelectric layer on a side of the substrate so as to correspond to the pressure generating chamber, and a second electrode that is formed on a surface of the piezoelectric layer opposite to the side on which the first electrode is formed so as to extend over a plurality of the pressure generating chambers, wherein the second electrode is formed to extend to an outside of the pressure generating chamber in a longitudinal direction of the pressure generating chamber.
    Type: Application
    Filed: October 18, 2016
    Publication date: February 9, 2017
    Inventors: Eiju HIRAI, Shiro YAZAKI, Koji SUMI, Motoki TAKABE, Jiro KATO, Hiroshi ITO, Toshihiro SHIMIZU, Takahiro KAMIJO, Tatsuro TORIMOTO, Chikara KOJIMA
  • Patent number: 9498952
    Abstract: A liquid ejection head includes a substrate in which a pressure generating chamber that communicates with a nozzle opening is formed; and a piezoelectric element having a piezoelectric layer, a first electrode that is formed on a surface of the piezoelectric layer on a side of the substrate so as to correspond to the pressure generating chamber, and a second electrode that is formed on a surface of the piezoelectric layer opposite to the side on which the first electrode is formed so as to extend over a plurality of the pressure generating chambers, wherein the second electrode is formed to extend to an outside of the pressure generating chamber in a longitudinal direction of the pressure generating chamber.
    Type: Grant
    Filed: November 16, 2015
    Date of Patent: November 22, 2016
    Assignee: Seiko Epson Corporation
    Inventors: Eiju Hirai, Shiro Yazaki, Koji Sumi, Motoki Takabe, Jiro Kato, Hiroshi Ito, Toshihiro Shimizu, Takahiro Kamijo, Tatsuro Torimoto, Chikara Kojima
  • Publication number: 20160284969
    Abstract: A piezoelectric element includes a first electrode formed on a substrate, a piezoelectric layer which is formed on the first electrode and includes a complex oxide with an ABO3-type perovskite structure represented by the following formula (1); and a second electrode formed on the piezoelectric layer, in which a seed layer including a complex oxide with an ABO3 perovskite structure in which K and Nb are included between the first electrode and the piezoelectric layer, and the piezoelectric layer is formed from a polycrystal that is preferentially orientated on the (110) plane.
    Type: Application
    Filed: March 23, 2016
    Publication date: September 29, 2016
    Inventors: Koji SUMI, Tomokazu KOBAYASHI, Kazuya KITADA
  • Publication number: 20160276572
    Abstract: A piezoelectric element includes a first electrode that is formed on a substrate, a piezoelectric layer that is formed on the first electrode and includes an ABO3 type complex oxide of the perovskite structure expressed by Formula (1) described below, and a second electrode that is formed on the piezoelectric layer, in which the piezoelectric layer is made of a polycrystal which is preferentially oriented to a (100) plane, and has a thickness of 50 nm or more and 2000 nm or less, and in the piezoelectric layer, a diffraction peak position (2?) of an X-ray derived from the (100) plane of the piezoelectric layer is 22.51° or more and 22.95° or less.
    Type: Application
    Filed: March 18, 2016
    Publication date: September 22, 2016
    Inventors: Koji SUMI, Tomokazu KOBAYASHI, Kazuya KITADA
  • Patent number: 9324933
    Abstract: A piezoelectric material contains a first component that is a rhombohedral crystal and that is configured to have a complex oxide with a perovskite structure and Curie temperature Tc1, a second component that is a crystal other than a rhombohedral crystal and that is configured to have a complex oxide with a perovskite structure and Curie temperature e Tc2, and a third component that is a rhombohedral crystal and that is configured to have a complex oxide with a perovskite structure and Curie temperature Tc3 different from the first component, and in which Tc2 is higher than Tc1, Tc3 is equal to or higher than Tc2, and a value of (0.1×Tc1+0.9×Tc2) is equal to or lower than 280° C.
    Type: Grant
    Filed: March 26, 2014
    Date of Patent: April 26, 2016
    Assignee: Seiko Epson Corporation
    Inventors: Koji Sumi, Kazuya Kitada, Tomohiro Sakai, Yasuaki Hamada, Tetsuya Isshiki, Satoshi Kimura, Akio Ito, Tsuneo Handa
  • Publication number: 20160075137
    Abstract: A liquid ejection head includes a substrate in which a pressure generating chamber that communicates with a nozzle opening is formed; and a piezoelectric element having a piezoelectric layer, a first electrode that is formed on a surface of the piezoelectric layer on a side of the substrate so as to correspond to the pressure generating chamber, and a second electrode that is formed on a surface of the piezoelectric layer opposite to the side on which the first electrode is formed so as to extend over a plurality of the pressure generating chambers, wherein the second electrode is formed to extend to an outside of the pressure generating chamber in a longitudinal direction of the pressure generating chamber.
    Type: Application
    Filed: November 16, 2015
    Publication date: March 17, 2016
    Inventors: Eiju HIRAI, Shiro YAZAKI, Koji SUMI, Motoki TAKABE, Jiro KATO, Hiroshi ITO, Toshihiro SHIMIZU, Takahiro KAMIJO, Tatsuro TORIMOTO, Chikara KOJIMA
  • Patent number: 9276193
    Abstract: A piezoelectric material contains a first component that is a rhombohedral crystal that is configured to have a complex oxide with a perovskite structure and Curie temperature Tc1, a second component that is a crystal other than a rhombohedral crystal that is configured to have a complex oxide with the perovskite structure and Curie temperature Tc2, and a third component that is configured to have a complex oxide with the perovskite structure in which the component is formed as the same crystal system as the second component and Curie temperature Tc3, in which Tc1 is higher than Tc2, and Tc3 is equal to or higher than Tc1.
    Type: Grant
    Filed: March 26, 2014
    Date of Patent: March 1, 2016
    Assignee: Seiko Epson Corporation
    Inventors: Koji Sumi, Kazuya Kitada, Tomohiro Sakai, Yasuaki Hamada, Tetsuya Isshiki, Satoshi Kimura, Akio Ito, Tsuneo Handa
  • Publication number: 20150367643
    Abstract: A liquid ejection head includes a substrate in which a pressure generating chamber that communicates with a nozzle opening is formed; and a piezoelectric element having a piezoelectric layer, a first electrode that is formed on a surface of the piezoelectric layer on a side of the substrate so as to correspond to the pressure generating chamber, and a second electrode that is formed on a surface of the piezoelectric layer opposite to the side on which the first electrode is formed so as to extend over a plurality of the pressure generating chambers, wherein the second electrode is formed to extend to an outside of the pressure generating chamber in a longitudinal direction of the pressure generating chamber.
    Type: Application
    Filed: August 28, 2015
    Publication date: December 24, 2015
    Inventors: Eiju HIRAI, Shiro YAZAKI, Koji SUMI, Motoki TAKABE, Jiro KATO, Hiroshi ITO, Toshihiro SHIMIZU, Takahiro KAMIJO, Tatsuro TORIMOTO, Chikara KOJIMA
  • Patent number: 9190601
    Abstract: A piezoelectric material contains a first component that is a rhombohedral crystal that is configured to have a complex oxide with a perovskite structure and Curie temperature Tc1 and a second component that is a crystal other than a rhombohedral crystal that is configured to have a complex oxide with the perovskite structure and Curie temperature Tc2, in which |Tc1?Tc2| is equal to or less than 50° C.
    Type: Grant
    Filed: March 26, 2014
    Date of Patent: November 17, 2015
    Assignee: Seiko Epson Corporation
    Inventors: Koji Sumi, Kazuya Kitada, Tomohiro Sakai, Yasuaki Hamada, Tetsuya Isshiki, Satoshi Kimura, Akio Ito, Tsuneo Handa
  • Patent number: 9144977
    Abstract: A liquid ejection head includes a substrate in which a pressure generating chamber that communicates with a nozzle opening is formed; and a piezoelectric element having a piezoelectric layer, a first electrode that is formed on a surface of the piezoelectric layer on a side of the substrate so as to correspond to the pressure generating chamber, and a second electrode that is formed on a surface of the piezoelectric layer opposite to the side on which the first electrode is formed so as to extend over a plurality of the pressure generating chambers, wherein the second electrode is formed to extend to an outside of the pressure generating chamber in a longitudinal direction of the pressure generating chamber.
    Type: Grant
    Filed: December 10, 2014
    Date of Patent: September 29, 2015
    Assignee: Seiko Epson Corporation
    Inventors: Eiju Hirai, Shiro Yazaki, Koji Sumi, Motoki Takabe, Jiro Kato, Hiroshi Ito, Toshihiro Shimizu, Takahiro Kamijo, Tatsuro Torimoto, Chikara Kojima
  • Publication number: 20150085024
    Abstract: A liquid ejection head includes a substrate in which a pressure generating chamber that communicates with a nozzle opening is formed; and a piezoelectric element having a piezoelectric layer, a first electrode that is formed on a surface of the piezoelectric layer on a side of the substrate so as to correspond to the pressure generating chamber, and a second electrode that is formed on a surface of the piezoelectric layer opposite to the side on which the first electrode is formed so as to extend over a plurality of the pressure generating chambers, wherein the second electrode is formed to extend to an outside of the pressure generating chamber in a longitudinal direction of the pressure generating chamber.
    Type: Application
    Filed: December 10, 2014
    Publication date: March 26, 2015
    Inventors: Eiju HIRAI, Shiro YAZAKI, Koji SUMI, Motoki TAKABE, Jiro KATO, Hiroshi ITO, Toshihiro SHIMIZU, Takahiro KAMIJO, Tatsuro TORIMOTO, Chikara KOJIMA
  • Publication number: 20150002585
    Abstract: A piezoelectric material contains a first component that is a rhombohedral crystal that is configured to have a complex oxide with a perovskite structure and Curie temperature Tc1, a second component that is a crystal other than a rhombohedral crystal that is configured to have a complex oxide with the perovskite structure and Curie temperature Tc2, and a third component that is configured to have a complex oxide with the perovskite structure in which the component is formed as the same crystal system as the second component and Curie temperature Tc3, in which Tc1 is higher than Tc2, and Tc3 is equal to or higher than Tc1.
    Type: Application
    Filed: March 26, 2014
    Publication date: January 1, 2015
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Koji SUMI, Kazuya KITADA, Tomohiro SAKAI, Yasuaki HAMADA, Tetsuya ISSHIKI, Satoshi KIMURA, Akio ITO, Tsuneo HANDA
  • Publication number: 20150002584
    Abstract: A piezoelectric material contains a first component that is a rhombohedral crystal that is configured to have a complex oxide with a perovskite structure and Curie temperature Tc1 and a second component that is a crystal other than a rhombohedral crystal that is configured to have a complex oxide with the perovskite structure and Curie temperature Tc2, in which |Tc1?Tc2| is equal to or less than 50° C.
    Type: Application
    Filed: March 26, 2014
    Publication date: January 1, 2015
    Applicant: Seiko Epson Corporation
    Inventors: Koji SUMI, Kazuya KITADA, Tomohiro SAKAI, Yasuaki HAMADA, Tetsuya ISSHIKI, Satoshi KIMURA, Akio ITO, Tsuneo HANDA
  • Publication number: 20150002586
    Abstract: A piezoelectric material contains a first component that is a rhombohedral crystal and that is configured to have a complex oxide with a perovskite structure and Curie temperature Tc1, a second component that is a crystal other than a rhombohedral crystal and that is configured to have a complex oxide with a perovskite structure and Curie temperature e Tc2, and a third component that is a rhombohedral crystal and that is configured to have a complex oxide with a perovskite structure and Curie temperature Tc3 different from the first component, and in which Tc2 is higher than Tc1, Tc3 is equal to or higher than Tc2, and a value of (0.1×Tc1+0.9×Tc2) is equal to or lower than 280° C.
    Type: Application
    Filed: March 26, 2014
    Publication date: January 1, 2015
    Applicant: Seiko Epson Corporation
    Inventors: Koji SUMI, Kazuya KITADA, Tomohiro SAKAI, Yasuaki HAMADA, Tetsuya ISSHIKI, Satoshi KIMURA, Akio ITO, Tsuneo HANDA
  • Publication number: 20140210916
    Abstract: A liquid ejection head includes a substrate in which a pressure generating chamber that communicates with a nozzle opening is formed; and a piezoelectric element having a piezoelectric layer, a first electrode that is formed on a surface of the piezoelectric layer on a side of the substrate so as to correspond to the pressure generating chamber, and a second electrode that is formed on a surface of the piezoelectric layer opposite to the side on which the first electrode is formed so as to extend over a plurality of the pressure generating chambers, wherein the second electrode is formed to extend to an outside of the pressure generating chamber in a longitudinal direction of the pressure generating chamber.
    Type: Application
    Filed: April 3, 2014
    Publication date: July 31, 2014
    Applicant: Seiko Epson Corporation
    Inventors: Eiju HIRAI, Shiro YAZAKI, Koji SUMI, Motoki TAKABE, Jiro KATO, Hiroshi ITO, Toshihiro SHIMIZU, Takahiro KAMIJO, Tatsuro TORIMOTO, Chikara KOJIMA
  • Patent number: 8764167
    Abstract: Provided is a method of manufacturing a liquid ejecting head including a pressure generating chamber communicating with a nozzle opening and a piezoelectric element including a piezoelectric layer and an electrode, the method including: forming a first piezoelectric precursor film containing Bi and Fe, or Ba and Ti; forming a first piezoelectric layer by heating and crystallizing the first piezoelectric precursor film; forming a second piezoelectric precursor film further containing at least one selected from Li, B, and Cu on the first piezoelectric layer, in addition to Bi and Fe, or Ba and Ti contained in the first piezoelectric precursor film; and forming the piezoelectric layer by heating and crystallizing the first piezoelectric layer and the second piezoelectric precursor film.
    Type: Grant
    Filed: February 25, 2013
    Date of Patent: July 1, 2014
    Assignee: Seiko Epson Corporation
    Inventors: Kazuya Kitada, Xiaoxing Wang, Koji Sumi
  • Patent number: 8727510
    Abstract: A liquid ejection head includes a substrate in which a pressure generating chamber that communicates with a nozzle opening is formed; and a piezoelectric element having a piezoelectric layer, a first electrode that is formed on a surface of the piezoelectric layer on a side of the substrate so as to correspond to the pressure generating chamber, and a second electrode that is formed on a surface of the piezoelectric layer opposite to the side on which the first electrode is formed so as to extend over a plurality of the pressure generating chambers, wherein the second electrode is formed to extend to an outside of the pressure generating chamber in a longitudinal direction of the pressure generating chamber.
    Type: Grant
    Filed: January 31, 2013
    Date of Patent: May 20, 2014
    Assignee: Seiko Epson Corporation
    Inventors: Eiju Hirai, Shiro Yazaki, Koji Sumi, Motoki Takabe, Jiro Kato, Hiroshi Ito, Toshihiro Shimizu, Takahiro Kamijo, Tatsuro Torimoto, Chikara Kojima
  • Patent number: 8459767
    Abstract: A liquid ejecting head includes a flow path forming substrate in which pressure generation chambers are formed. The pressure generation chambers communicate with nozzles that eject liquid droplets. Piezoelectric elements are positioned on the flow path forming substrate to generate pressure changes in the pressure generation chambers. Each piezoelectric element includes a piezoelectric body layer, a first electrode on one side of the piezoelectric body layer, and a second electrode on the opposite side of the piezoelectric body layer. The piezoelectric element is driven in a condition that the relationship between minimum voltage Vmin, and maximum voltage Vmax, which are applied to the piezoelectric element, and peak voltage Vo satisfies the expression, Vmin<Vo<Vmax. In this expression, the peak voltage Vo is a voltage value at which a primary differential coefficient of displacement by voltage, which is obtained from a displacement-voltage curve, is at a maximum value.
    Type: Grant
    Filed: April 9, 2010
    Date of Patent: June 11, 2013
    Assignee: Seiko Epson Corporation
    Inventor: Koji Sumi
  • Patent number: 8317304
    Abstract: A liquid ejecting head is equipped with a piezoelectric element. The piezoelectric element has a piezoelectric layer containing titanium (Ti) and zirconium (Zr) and first and second electrodes provided on both faces of the piezoelectric layer. The composition ratio of Ti and Zr in the piezoelectric layer Ti/(Zr+Ti) is in the range of 0.50 to 0.60 both inclusive. The piezoelectric layer contains rhombohedral crystals at least in a portion thereof covering the first electrode.
    Type: Grant
    Filed: March 11, 2010
    Date of Patent: November 27, 2012
    Assignee: Seiko Epson Corporation
    Inventor: Koji Sumi
  • Patent number: 8277031
    Abstract: A liquid-ejecting head includes a flow-passage-forming substrate that includes a pressure-generating chamber, the pressure-generating chamber being in communication with a nozzle through which droplets are ejected, and a piezoelectric element disposed on the flow-passage-forming substrate, the piezoelectric element altering the internal pressure of the pressure-generating chamber. The piezoelectric element includes a piezoelectric layer containing titanium (Ti) and zirconium (Zr), a first electrode, and a second electrode. The first electrode and the second electrode are disposed on the opposite sides of the piezoelectric layer,. The component ratio Ti/(Zr+Ti) of the piezoelectric layer is 0.40 or more but less than 0.50. At least a portion of the piezoelectric layer formed on the first electrode contains tetragonal crystals formed by phase transition under stress caused by an underlying layer.
    Type: Grant
    Filed: April 6, 2010
    Date of Patent: October 2, 2012
    Assignee: Seiko Epson Corporation
    Inventor: Koji Sumi