Patents by Inventor Norikazu Niimi

Norikazu Niimi 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: 7843137
    Abstract: The inventive luminous vessel has strong bonding and improved adhesion of the current through conductor provided in the luminous container to a sealing member or the like. A luminous vessel has a luminous container, a solid current through conductor made of a metal or a cermet and a sintered body of a molded body containing at least metal powder fixed to the outside of the current through conductor.
    Type: Grant
    Filed: March 29, 2006
    Date of Patent: November 30, 2010
    Assignee: NGK Insulators, Ltd.
    Inventors: Keiichiro Watanabe, Takashi Ota, Norikazu Niimi
  • Patent number: 7371704
    Abstract: An object of the present invention is to lower the sintering temperature required for a sintered body of yttrium-aluminum garnet, to improve the corrosion resistance of the sintered body and to prevent the reduction of the transmittance thereof. A sintered body of yttrium-aluminum garnet is produced from a source compound for yttrium and a source compound for aluminum using aluminum nitride as a sintering aid. It maybe considered that aluminum nitride reacts with alumina and yttria to generate liquid phase and to reduce the sintering temperature during the sintering process.
    Type: Grant
    Filed: December 8, 2003
    Date of Patent: May 13, 2008
    Assignee: NGK Insulators, Ltd.
    Inventor: Norikazu Niimi
  • Patent number: 7301282
    Abstract: An object of the invention is to reduce the adverse effects due to a difference of thermal expansion between a conductive sealing member and a light-emitting vessel and to provide a reliable high pressure mercury lamp, even when the lamp is operated at a high pressure. The lamp has a light-emitting vessel 16 of quartz and having end portions, an electrode member 10 contained in the vessel 16, and a conductive sealing member 7A. The sealing member 7A is fixed in the end portion and connected to the electrode member 10. The conductive member is composed of a sintered body made from silica granules each having a coating of a metal or a metal compound. The sintered body has a conductive network structure made of the metal and having a content of the metal of not higher than 20 volume percent.
    Type: Grant
    Filed: May 14, 2003
    Date of Patent: November 27, 2007
    Assignee: NGK Insulators, Ltd.
    Inventor: Norikazu Niimi
  • Patent number: 7187128
    Abstract: A joined body is provided, including a first member having a first joining face and sapphire exposed at the first joining face and a second member having a second joining face and sapphire or polycrystalline alumina exposed at the second joining face. The first member and second member are joined by providing a raw material for the joining material between the first and second members and heat treating the raw material at a temperature of 1730° C. or lower.
    Type: Grant
    Filed: May 24, 2004
    Date of Patent: March 6, 2007
    Assignee: NGK Insulators, Ltd.
    Inventor: Norikazu Niimi
  • Patent number: 7132798
    Abstract: The present invention provides a joined body having a first member 7, a second member 4 and a joining material 14 interposed between the first and second members. The joining material has a porous bone structure 15 with open pores and made of a sintered product of metal powder and impregnated phase 10 impregnated into the open pores. The impregnated phase 10 includes an oxynitride glass. The joined body has improved resistance against fatigue and fracture, even when the body is subjected to thermal cycles between high and room temperatures and held at a high temperature over a long period of time.
    Type: Grant
    Filed: May 2, 2003
    Date of Patent: November 7, 2006
    Assignee: NGK Insulators, Ltd.
    Inventor: Norikazu Niimi
  • Patent number: 7126280
    Abstract: The present invention provides a joined body having a first member, a second member and a joining material interposed between the first and second members. The joining material has a porous bone structure with open pores and made of a sintered product of metal powder and impregnated phase impregnated into the open pores. The impregnated phase has polycrystalline substance made from a metal oxide and at least one of a nitride and an oxynitride. The joined body has improved resistance against fatigue and fracture, even when the body is subjected to repeated thermal cycles between high and room temperatures.
    Type: Grant
    Filed: September 8, 2004
    Date of Patent: October 24, 2006
    Assignee: NGK Insulators, Ltd.
    Inventor: Norikazu Niimi
  • Publication number: 20060220558
    Abstract: The inventive luminous vessel has a strong bonding and improved adhesion of a current through conductor 2 provided in a luminous container 9 to a sealing member 11C or the like. A luminous vessel has a luminous container 9, a solid current through conductor 2 made of a metal or a cermet and a sintered body 11C of a molded body containing at least metal powder fixed to the outside of the current through conductor 2.
    Type: Application
    Filed: March 29, 2006
    Publication date: October 5, 2006
    Applicant: NGK Insulators, Ltd.
    Inventors: Keiichiro Watanabe, Takashi Ota, Norikazu Niimi
  • Publication number: 20060222878
    Abstract: The present invention provides a composite body having a strong bonding and improved adhesion. A composite body 3 has a solid and elongate body 2 made of a metal and a sintered body 11 of metal powder fixed to the outside of the elongate body so that the sintered body applies a stress onto the outside of elongate body radially.
    Type: Application
    Filed: March 29, 2006
    Publication date: October 5, 2006
    Applicant: NGK Insulators, Ltd.
    Inventors: Keiichiro Watanabe, Takashi Ota, Norikazu Niimi
  • Patent number: 7001570
    Abstract: A metal-made seamless pipe is provided, containing at least one metal selected from the group consisting of metals each having a melting point of 1,600° C. or more, and has a porosity of 0.3 to 25%. The porosity is defined as a ratio of the open pores present at the outer surface of the pipe to the total surface area of the outer surface of the pipe. The open pores do not include through-pores perforating to the inner surface of the pipe. A process for producing such a metal-made seamless pipe is also provided. The metal-made seamless pipe is low in processability but can be produced having a small thickness and a small inner diameter, having superior mechanical strength and gastightness, and can be suitably used as a sealing member of a translucent vessel of a high-pressure discharge lamp.
    Type: Grant
    Filed: April 25, 2003
    Date of Patent: February 21, 2006
    Assignee: NGK Insulators, Ltd.
    Inventor: Norikazu Niimi
  • Publication number: 20050275142
    Abstract: An object of the present invention is to provide a method suitable for producing a translucent ceramic. A slurry containing a powdery raw material having a mean particle diameter of 0.3 ?m or smaller, a dispersing medium and a gelling agent is cast into a mold and gelled to obtain a molded body. The molded body is then sintered. Preferably, the molded body is sintered under ambient pressure.
    Type: Application
    Filed: June 3, 2005
    Publication date: December 15, 2005
    Applicant: NGK Insulators, Ltd.
    Inventor: Norikazu Niimi
  • Publication number: 20050093453
    Abstract: The present invention provides a joined body having a first member, a second member and a joining material interposed between the first and second members. The joining material has a porous bone structure with open pores and made of a sintered product of metal powder and impregnated phase impregnated into the open pores. The impregnated phase has polycrystalline substance made from a metal oxide and at least one of a nitride and an oxynitride. The joined body has improved resistance against fatigue and fracture, even when the body is subjected to repeated thermal cycles between high and room temperatures.
    Type: Application
    Filed: September 8, 2004
    Publication date: May 5, 2005
    Applicant: NGK INSULATORS, LTD.
    Inventor: Norikazu Niimi
  • Patent number: 6850009
    Abstract: A high pressure discharge lamp including a ceramic discharge tube defining an inner space and having an opening formed within an end portion thereof, an electrode system provided within the inner space, a sealing member including a ceramic or a cermet with a through hole formed therein, at least a part of the sealing member being fixed within the opening of the ceramic discharge tube, and a metal member. A joining portion is interposed between the metal and sealing members, and includes a main phase contacting the metal member and an intermediate ceramic layer contacting the sealing member and existing between the sealing member and the main phase. The main phase includes a porous bone structure with open pores, is made of a sintered product of metal powder, and includes a ceramic phase impregnated into the open pores thereof.
    Type: Grant
    Filed: December 4, 2003
    Date of Patent: February 1, 2005
    Assignee: NGK Insulators, Ltd.
    Inventor: Norikazu Niimi
  • Patent number: 6844677
    Abstract: A joined body is provided, including a joining portion interposed between a first member wade of a metal and a second member, made of a ceramic or a cermet that joins the first and second members. The joining portion includes a main phase contacting the first member and an intermediate glass layer between the second member and the main phase. The main phase is composed of a porous bone structure having open pores and is made of a sintered product of metal powder. A glass phase is impregnated into the open pores in the porous bone structure. Preferably, the glasses of the intermediate glass layer and the impregnated glass phase have substantially the same composition.
    Type: Grant
    Filed: July 28, 2003
    Date of Patent: January 18, 2005
    Assignee: NGK Insulators, Ltd.
    Inventor: Norikazu Niimi
  • Publication number: 20040239227
    Abstract: An object of the present invention is to provide a joined body of a first member comprising a first joining face and sapphire exposed at the first joining face and a second member comprising a second joining face and sapphire or polycrystalline alumina exposed at the second joining face, so that the joining strength can be improved and crack formation along the joining interface can be prevented. The first member 2 and second members 4A, 4B are joined with each other by providing a raw material for the joining material between the first and second members and heat treating the raw material at a temperature of 1730° C. or lower. Alternatively, The joining materials 5A, 5B comprise an oxide or an oxynitride containing a rare earth element, aluminum and silicon, and wherein the oxide or oxynitride has a silicon content of 3 mole percent or higher and 10 mole percent or lower calculated as silicon dioxide.
    Type: Application
    Filed: May 24, 2004
    Publication date: December 2, 2004
    Applicant: NGK Insulators, Ltd.
    Inventor: Norikazu Niimi
  • Patent number: 6819047
    Abstract: A ceramic discharge vessel having end portions and an inner space formed therein is filled with an ionizable light emitting substance and a starter gas. The end portion has an inner wall surface facing an opening formed in the end portion. A hollow portion is formed in the conductive member. The conductive member is inserted into the opening of the end portion of the vessel. A joining layer joins the inner wall surface of the end portion and the outer surface of the conductive member. A recess facing the opening is formed in the end portion, and the recess extends circumferentially with respect to the central axis “X” of the vessel. When the conductive member is inserted into the opening of the end portion of the vessel and joined, the adherence or residue of joining material onto the end face or inner surface of the conductive member may be prevented.
    Type: Grant
    Filed: January 6, 2003
    Date of Patent: November 16, 2004
    Assignee: NGK Insulators, Ltd.
    Inventor: Norikazu Niimi
  • Patent number: 6812642
    Abstract: The invention provides a joined body of a first member made of a metal and a second member made of a ceramic or a cermet. The joined body comprises a joining portion interposed between the first member and the second member for joining the first and second members. The joining portion comprises main phase contacting the first member and an intermediate ceramic layer existing between the second member and the main phase and contacting the second member. The main phase is composed of a porous bone structure having open pores and is made of a sintered product of metal powder, and a ceramic phase impregnated into the open pores in the porous bone structure. The joined structure has resistance to fatigue and fracture, even when the structure is subjected to repeated thermal cycles between a high temperature, for example 1000° C. or higher, and room temperature.
    Type: Grant
    Filed: July 16, 2003
    Date of Patent: November 2, 2004
    Assignee: NGK Insulators, Ltd.
    Inventor: Norikazu Niimi
  • Patent number: 6791267
    Abstract: A high pressure discharge lamp 1A has a light emitting vessel 2A made of a semitransparent ceramic material and having a pair of end portions 2a each with an opening formed in the end portion and a light emitting portion 2a, a pair of discharge electrodes 5, and electrode supporting members 4 each supporting the electrode 5 and fixed to the end portion 2a. The vessel 2A defines an inner space 6 with an ionizable light emitting substance and starter gas filled in the inner space 6. The electrodes 5 are contained in the inner space 6. The light emitting portion 2b has a thicker portion 2g and a thinner portion 2c. The thinner portion 2c has a cross sectional area of not smaller than 35 percent and not larger than 80 percent of that of the thicker portion 2g so that the light emitting portion 2b has a brightness center 9 in the thinner portion 2c.
    Type: Grant
    Filed: September 23, 2002
    Date of Patent: September 14, 2004
    Assignee: NGK Insulators, Ltd.
    Inventor: Norikazu Niimi
  • Publication number: 20040135295
    Abstract: An object of the present invention is to lower the sintering temperature required for a sintered body of yttrium-aluminum garnet, to improve the corrosion resistance of the sintered body and to prevent the reduction of the transmittance thereof. A sintered body of yttrium-aluminum garnet is produced from a source compound for yttrium and a source compound for aluminum using aluminum nitride as a sintering aid. It maybe considered that aluminum nitride reacts with alumina and yttria to generate liquid phase and to reduce the sintering temperature during the sintering process.
    Type: Application
    Filed: December 8, 2003
    Publication date: July 15, 2004
    Applicant: NGK INSULATORS, LTD.
    Inventor: Norikazu Niimi
  • Publication number: 20040119392
    Abstract: A high pressure discharge lamp including a ceramic discharge tube defining an inner space and having an opening formed within an end portion thereof, an electrode system provided within the inner space, a sealing member including a ceramic or a cermet with a through hole formed therein, at least a part of the sealing member being fixed within the opening of the ceramic discharge tube, and a metal member. A joining portion is interposed between the metal and sealing members, and includes a main phase contacting the metal member and an intermediate ceramic layer contacting the sealing member and existing between the sealing member and the main phase. The main phase includes a porous bone structure with open pores, is made of a sintered product of metal powder, and includes a ceramic phase impregnated into the open pores thereof.
    Type: Application
    Filed: December 4, 2003
    Publication date: June 24, 2004
    Applicant: NGK Insulators, Ltd.
    Inventor: Norikazu Niimi
  • Publication number: 20040070343
    Abstract: A joined body including a joining portion 6 interposed between a first member, made of a metal, and a second member 4, made of a ceramics or a cermet, for joining the first and second members. The joining portion 6 includes main phase 14 contacting the first member and an intermediate glass layer 13 existing between the second member 4 and the main phase 14. The main phase 14 is composed of a porous bone structure 15, with open pores and made of a sintered product of metal powder, and a glass phase 10 impregnated into the open pores in the porous bone structure. Preferably, the intermediate glass layer 13 and impregnated glass phase 10 is composed of glasses of substantially the same composition.
    Type: Application
    Filed: July 28, 2003
    Publication date: April 15, 2004
    Applicant: NGK Insulators, Ltd.
    Inventor: Norikazu Niimi