Patents by Inventor Masaki Iwaya

Masaki Iwaya 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: 7556745
    Abstract: A sintered body for thermistor element of the invention is a sintered body for thermistor element containing Sr, Y, Mn, Al, Fe, and O, wherein not only respective liquid crystal phases of a perovskite type oxide and a garnet type oxide are contained, but also a liquid crystal phase of at least one of an Sr—Al based oxide and an Sr—Fe based oxide. FeYO3 and/or AlYO3 is selected as the foregoing perovskite type oxide, and at least one member selected from Y3Al5O12, Al2Fe3Y3O12, and Al3Fe2Y3O12 is selected as the foregoing garnet type oxide, respectively by the powder X-ray diffraction analysis.
    Type: Grant
    Filed: May 19, 2003
    Date of Patent: July 7, 2009
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Takaaki Chosokabe, Masaki Iwaya, Naoki Yamada, Wakako Takano
  • Patent number: 7232527
    Abstract: A sintered body for thermistor device comprising: at least one element selected from elements of group 3 in a periodic table proviso that La is excluded; at least one element selected from elements of group 2 in a periodic table; Mn; Al; and oxygen, and being substantially free from any transition metal other than Mn and the at least one element selected from elements of group 3 in the periodic table.
    Type: Grant
    Filed: December 1, 2003
    Date of Patent: June 19, 2007
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Takaaki Chosokabe, Masaki Iwaya, Naoki Yamada
  • Patent number: 7104685
    Abstract: A temperature sensor (1) including a cylindrical metal tube (3) having a front end side blocked, a thermistor element (2), and a sheath member (8) connected to the thermistor element (2) and held in the inside of the metal tube (3), wherein: the metal tube (3) has a small-diameter portion (33) located on the front end side and entirely having an inner diameter smaller than the outer diameter of the sheath member (8), and a large-diameter portion (36) located on the rear end side of the small-diameter portion (33) and having a diameter larger than the outer diameter of the small-diameter portion (33); and a thermistor sintered body (21) is held in the small-diameter portion (33) and cement (10) is filled in between a front end of the thermistor sintered body (21) and a front end of an inner wall of the metal tube (3) and on the front end side viewed from a rear end surface of the thermistor sintered body (21).
    Type: Grant
    Filed: March 25, 2004
    Date of Patent: September 12, 2006
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Go Hanzawa, Masahiko Nishi, Masaki Iwaya, Takaaki Chosokabe
  • Publication number: 20060186385
    Abstract: A sintered body for thermistor element of the invention is a sintered body for thermistor element containing Sr, Y, Mn, Al, Fe, and O, wherein not only respective liquid crystal phases of a perovskite type oxide and a garnet type oxide are contained, but also a liquid crystal phase of at least one of an Sr—Al based oxide and an Sr—Fe based oxide. FeYO3 and/or AlYO3 is selected as the foregoing perovskite type oxide, and at least one member selected from Y3Al5O12, Al2Fe3Y3O12, and Al3Fe2Y3O12 is selected as the foregoing garnet type oxide, respectively by the powder X-ray diffraction analysis.
    Type: Application
    Filed: May 19, 2003
    Publication date: August 24, 2006
    Applicant: NGK Spark Plug Company, Ltd.
    Inventors: Takaaki Chosokabe, Masaki Iwaya, Naoki Yamada, Wakato Takano
  • Patent number: 6997607
    Abstract: A cylindrical metal tube (3) accommodating therein a thermistor device (2), the electric characteristics of which change with temperature, is pushed into, or clamped and fixed to, a sheath portion (42) positioned on a flange (4) to the rear of a projection portion (41) of the flange (4), and is laser welded in a circumferential direction. A weld portion (L1) formed to bridge the metal tube (3) and the sheath portion (42) of the flange (4) firmly fixes the metal tube (3) to the flange (4). In the temperature sensor (1) having this construction, the weld portion (L1) between the metal tube (3) and the flange (4) is not exposed to a high temperature environment. Therefore, oxidation hardly occurs at the weld portion and reliability of air tightness to an exhaust gas can be improved.
    Type: Grant
    Filed: November 22, 2002
    Date of Patent: February 14, 2006
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Masaki Iwaya, Masahiko Nishi, Takaaki Chosokabe, Masaru Hayakawa
  • Patent number: 6997604
    Abstract: A temperature sensor comprising: a housing; a thermo-sensitive element housed in the housing for outputting electric characteristics varying with a temperature, as an electric signal; and a pair of lead wires connected at their one-side ends with the thermo-sensitive element for extracting the electric signal from the thermo-sensitive element to an outside of the housing, wherein at least one of the lead wires is made of a mixed twisted wire including: first electric wires made of a first conductor containing copper; and second electric wires made of a second conductor having a higher bending resistance and a tensile strength than those of the first conductor.
    Type: Grant
    Filed: January 7, 2004
    Date of Patent: February 14, 2006
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Go Hanzawa, Masahiko Nishi, Masaki Iwaya, Takaaki Chosokabe
  • Publication number: 20050265426
    Abstract: An object of the present invention is to attain greater improvement of response characteristic in a temperature sensor having a thermistor element held in a metal tube.
    Type: Application
    Filed: March 25, 2004
    Publication date: December 1, 2005
    Inventors: Go Hanzawa, Masahiko Nishi, Masaki Iwaya, Takaaki Chosokabe
  • Publication number: 20040159825
    Abstract: A sintered body for thermistor device comprising: at least one element selected from elements of group 3 in a periodic table proviso that La is excluded; at least one element selected from elements of group 2 in a periodic table; Mn; Al; and oxygen, and being substantially free from any transition metal other than Mn and the at least one element selected from elements of group 3 in the periodic table.
    Type: Application
    Filed: December 1, 2003
    Publication date: August 19, 2004
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Takaaki Chosokabe, Masaki Iwaya, Naoki Yamada
  • Publication number: 20040135664
    Abstract: A temperature sensor comprising: a housing; a thermo-sensitive element housed in the housing for outputting electric characteristics varying with a temperature, as an electric signal; and a pair of lead wires connected at their one-side ends with the thermo-sensitive element for extracting the electric signal from the thermo-sensitive element to an outside of the housing, wherein at least one of the lead wires is made of a mixed twisted wire including: first electric wires made of a first conductor containing copper; and second electric wires made of a second conductor having a higher bending resistance and a tensile strength than those of the first conductor.
    Type: Application
    Filed: January 7, 2004
    Publication date: July 15, 2004
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Go Hanzawa, Masahiko Nishi, Masaki Iwaya, Takaaki Chosokabe
  • Publication number: 20040101028
    Abstract: A cylindrical metal tube (3) accommodating therein a thermistor device (2), the electric characteristics of which change with temperature, is pushed into, or clamped and fixed to, a sheath portion (42) positioned on a flange (4) to the rear of a projection portion (41) of the flange (4), and is laser welded in a circumferential direction. A weld portion (L1) formed to bridge the metal tube (3) and the sheath portion (42) of the flange (4) firmly fixes the metal tube (3) to the flange (4). In the temperature sensor (1) having this construction, the weld portion (L1) between the metal tube (3) and the flange (4) is not exposed to a high temperature environment. Therefore, oxidation hardly occurs at the weld portion and reliability of air tightness to an exhaust gas can be improved.
    Type: Application
    Filed: November 22, 2002
    Publication date: May 27, 2004
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Masaki Iwaya, Masahiko Nishi, Takaaki Chosokabe, Masaru Hayakawa
  • Patent number: 5637543
    Abstract: A ceramic composition for thermistor exhibiting stable resistance values over a wide temperature range and capable of being used for a prolonged time. The composition is represented by (M.sup.1 M.sup.2 O.sub.3).sub.1-x .multidot.(M.sup.1 AlO.sub.3).sub.x, wherein M.sup.1 is an element selected from the elements of the group 3A excluding La and M.sup.2 is an element of the groups 4A, 5A, 6A, 7A and 8, and wherein the mixing ratio between an electrically conductive substance stable at elevated temperatures and an insulating substance stable at elevated temperatures, may be adjusted. A thermistor formed of the composition is superior in high-temperature stability and can be used over a broad temperature range because its resistance value can be selected to an optimum value.
    Type: Grant
    Filed: December 18, 1995
    Date of Patent: June 10, 1997
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Masaki Iwaya, Kyohei Hayashi, Hiroshi Matsuzaki, Yoshirou Suematsu
  • Patent number: 5610111
    Abstract: Ceramic composition for thermistor for detecting elevated temperatures which exhibits stable properties at elevated temperatures for permitting use in both oxidizing and reducing atmospheres. In a YCrO.sub.3 based material, Sr or Sm is partly or completely substituted for Y, and Fe and Ti are substituted for part of Cr. Such material enables the production of a thermistor element exhibiting practical, low resistance values at 300.degree. to 1100.degree. C. and also exhibiting stability against changes in the environmental conditions or thermal hysteresis. Generally AMO.sub.3 perovskite structure (A=2A,3A,3B subgroup elements, M=4A,5A,6A,8 subgroup elements) having a combination of n-type and p-type components provides the same property, the subgroup being of IUPAC international periodic table. La-free is preferred and sintering aid may be used.
    Type: Grant
    Filed: November 21, 1994
    Date of Patent: March 11, 1997
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Masaki Iwaya, Kyohei Hayashi
  • Patent number: 5568116
    Abstract: A ceramic composition for a thermistor of the formula (M.sup.1.sub.1-x.N.sup.1.sub.x)(P.sup.2.sub.1-y-z.N.sup.2.sub.y.Al.sub.z)O .sub.3 where M.sup.1 is one or more elements selected from the group 3A elements of the Periodic Table excluding La, N.sup.1 is one or more selected from the group 2A elements of the Periodic Table, P.sup.2 is one or more selected from the elements of the groups 4A, 5A, 6A, 7A and 8 of the Periodic Table whose oxides exhibit p-type characteristics, and N.sup.2 is one or more selected from the elements of the groups 4A, 5A, 6A, 7A and 8 whose oxides exhibit n-type characteristics,wherein x, y and z are larger than 0 and smaller than 1 and 0.001.ltoreq.x/(1-y-z)<0.20, 0.05.ltoreq.y/(1-y-z).ltoreq.0.80 and 0<z/(1-y-z).ltoreq.0.90. Thermistor elements are usable within a broad temperature range of 300.degree.-1100.degree. C., have a stable resistance in oxidizing and reducing atmospheres, can prevent deterioration of lead wires, and have superior stability at high temperatures.
    Type: Grant
    Filed: May 24, 1994
    Date of Patent: October 22, 1996
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Masaki Iwaya, Kyohei Hayashi, Hiroshi Matsuzaki, Yoshirou Suematsu
  • Patent number: 5476822
    Abstract: A ceramic composition for thermistor exhibiting stable resistance values over a wide temperature range and capable of being used for a prolonged time. The composition is represented by (M.sup.1 M.sup.2 O.sub.3).sub.1-x .multidot.(M.sup.1 AlO.sub.3).sub.x, wherein M.sup.1 is an element selected from the elements of the group 3A of the International Periodic Table excluding La and M.sup.2 is an element of the groups 4A, 5A, 6A, 7A and 8 of the International Periodic Table, and wherein the mixing ratio between an electrically conductive substance stable at elevated temperatures and an insulating substance stable at elevated temperatures, may be adjusted. A thermistor formed of the composition is superior in high-temperature stability and can be used over a broad temperature range because its resistance value can be selected to an optimum value.
    Type: Grant
    Filed: May 9, 1994
    Date of Patent: December 19, 1995
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Masaki Iwaya, Kyohei Hayashi, Hiroshi Matsuzaki, Yoshirou Suematsu