Patents by Inventor Yukihito Ichikawa

Yukihito Ichikawa 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: 20060185335
    Abstract: There is disclosed a method of manufacturing a plugged honeycomb structure, capable of simply manufacturing a plugged honeycomb structure which can avoid a phenomenon of rapid increase of pressure losses generated by cell openings clogged with particulate matters on an inlet side.
    Type: Application
    Filed: January 30, 2006
    Publication date: August 24, 2006
    Applicant: NGK INSULATORS, LTD.
    Inventor: Yukihito Ichikawa
  • Publication number: 20060168908
    Abstract: There are provided a honeycomb structure and a method of manufacturing the honeycomb structure, the honeycomb structure including a honeycomb structural part, which has partition walls 2 for forming a plurality of cells 3 partitioned in a honeycomb shape and for forming recesses 6 on an outer peripheral surface, and an outer wall part 5 disposed on the outer peripheral surface of the honeycomb structural part, wherein voids are formed in the recesses 6 between the outer wall part 5 and the honeycomb structural part. The honeycomb structure and the method of manufacturing the same can suppress the reduction of a temperature increasing speed while suppressing a decrease of mechanical strength and further can suppress the occurrence of cracks.
    Type: Application
    Filed: September 7, 2004
    Publication date: August 3, 2006
    Applicant: NGK INSULATORS, LTD.
    Inventors: Yukihito Ichikawa, Sadaaki Hirai
  • Publication number: 20060150598
    Abstract: There is provided a plugged honeycomb structure 1 including: partition walls 2 disposed so as to form a plurality of cells 3 extending from one end face 42 to the other end face 44 in the axial direction, and plugged portions 4 disposed so as to plug the cells 3 at one of the end faces, and a production method thereof. In this honeycomb structure 1, the plugged portions 4 and partition walls surrounding the plugged portions are unitarily formed. The production method includes a forming step, a plugging step for filling a plugging material, and a firing step. The plugging material contains solid particles capable of unitarily joining with at least one kind of solid particles contained in a forming raw material in a firing step. A ratio of a dimensional change (%) upon forming the partition walls out of the partition wall-forming material to a dimensional change (%) upon forming the plugged portions out of the plugging material is controlled to be within the range of 0.7% to 1.3 in the firing step.
    Type: Application
    Filed: March 19, 2004
    Publication date: July 13, 2006
    Applicant: NGK Insulators, LTD.
    Inventors: Yukihito Ichikawa, Yasushi Noguchi
  • Patent number: 7056365
    Abstract: A honeycomb structure in which a plurality of through-holes 3 extending in the axial direction are formed by a plurality of partition walls 1 and 2, wherein the plurality of partition walls 1 and 2 are constituted by a plurality of partition walls having different thicknesses and, of the plurality of partition walls having different thicknesses, those partition walls 2 having a thickness larger than the average thickness of all partition walls are provided at a higher proportion in a particular portion of the honeycomb structure whole portion having partition walls than in other portion. This honeycomb structure, and a honeycomb filter and a converter system both using the honeycomb structure satisfy recent years' requirements of improvement in warm-up property connected with purification ability and reduction in harmful substance emitted right after engine start, and yet have a sufficient mechanical strength to external pressure, a high erosion resistance and a high thermal shock resistance.
    Type: Grant
    Filed: April 26, 2002
    Date of Patent: June 6, 2006
    Assignee: NGK Insulators, Ltd.
    Inventors: Yukihito Ichikawa, Yasushi Kato, Masato Ogawa
  • Patent number: 7022376
    Abstract: A thin-walled honeycomb structure includes: a circumferential wall, numerous partition walls disposed inside the circumferential wall, and numerous cell passages defined by the partition walls. A circumferential portion of the honeycomb structure is reinforced wholly or in a part within a certain distance from an extremity surface of the honeycomb structure by a reinforcing material that dissipates or evaporates at a high temperature, and a method for producing the same.
    Type: Grant
    Filed: July 23, 2003
    Date of Patent: April 4, 2006
    Assignee: NGK Insulators, Ltd.
    Inventors: Yukihito Ichikawa, Koichi Ikeshima
  • Publication number: 20060029769
    Abstract: There is disclosed a plugged honeycomb structure 1 having: partition walls 2 arranged in such a manner as to form a plurality of cells 3 extending from one end face 42 to the other end face 44 through an axial direction; an outer peripheral wall 7 which surrounds an outer periphery of the partition wall 2; and plugging portions 4a, 4b disposed in such a manner as to plug the cell 3 in either end face 42, 44. In the plugged honeycomb structure 1, at least some of plugging portions 4a arranged in at least the vicinity of the outer peripheral wall protrude from the end face 42 or 44. Alternatively, there are provided a plugged honeycomb structure 1 in which a tip of the protruding portion 4a is substantially flat or has a moderate curved face, and a method of manufacturing the structure. The plugged honeycomb structure 1 does not easily break, is capable of enhancing durability, and is preferably usable in a filter such as a diesel particulate filter (DPF).
    Type: Application
    Filed: December 10, 2003
    Publication date: February 9, 2006
    Applicant: NGK INSULATORS, LTD.
    Inventors: Yukihito Ichikawa, Mitsuru Miyamoto, Shinya Mori
  • Publication number: 20050241266
    Abstract: The present invention provides a honeycomb structure which includes a cell structure section 3 including a plurality of cells 2 partitioned by a plurality of partition walls 1a and 1b, and an outer circumferential wall section 4 surrounding the cell structure section 3. The cell structure section 3 includes a first partition wall group having the partition walls 1a positioned in parallel and a second partition wall group having the partition walls 1b which intersect the partition walls of the first partition wall group at right angles and are positioned in parallel, each of the partition walls 1a and 1b connecting two different locations of the outer circumferential wall section 4 through one continuous plane.
    Type: Application
    Filed: September 4, 2003
    Publication date: November 3, 2005
    Applicant: NGK Insulators, Ltd.
    Inventor: Yukihito Ichikawa
  • Patent number: 6948243
    Abstract: A method for assembling a cell structure in a metal vessel, including reading information as indicia located on a surface of a compressible material having a cushioning property, the information regarding the thickness and/or bulk density of the compressible material; selecting a cell structure, a metal vessel, and a compressible material which, when assembled as a cell structure housed in a metal vessel, have a proper holding condition based on the read information; assembling the selected cell structure in the selected metal vessel via the selected compressible material, the compressible material being located in a compressed state between an outer periphery of the cell structure and the metal vessel to hold the selected cell structure in the selected metal vessel.
    Type: Grant
    Filed: November 16, 2001
    Date of Patent: September 27, 2005
    Assignee: NGK Insulators, Ltd.
    Inventors: Yukihito Ichikawa, Eiji Ito, Koichi Ikeshima, Masayasu Ishikawa
  • Publication number: 20050129590
    Abstract: A honeycomb structure of the present invention is a honeycomb structure 1 including: a cell structural part 2 including a plurality of cells 6 partitioned by partition walls 4 in a honeycomb shape to form flow paths allowing a fluid to flow therein; and an outer wall 3 disposed on an outer peripheral surface 7 of the cell structural part 2, characterized in that an outermost peripheral cell 9 of the cell structural part 2 and a predetermined number of cells positioned in an inner direction from the outermost peripheral cell among the cells 6 are sealed by an inner peripheral surface of the outer wall 3 in an end portion and/or an intermediate portion of at least one of the outermost peripheral cell and the outer peripheral cell in a central axis direction to constitute shielded cells 11, a temperature rising time of the cell structural part 2 after start of an operation shortens, and a catalytic activity can be enhanced in a short time when a catalyst is supported.
    Type: Application
    Filed: February 13, 2003
    Publication date: June 16, 2005
    Applicant: NGK INSULATORS, LTD
    Inventor: Yukihito Ichikawa
  • Publication number: 20050107244
    Abstract: A cell structure 10 having a plurality of cells 2 which are partitioned with partition walls 1 to form a honeycomb and which are flow paths of fluid, an outer wall 5 which encloses the cells 2 and a cavity 3 which pierces in the direction of a central axis P of the structure through a portion including the central axis P or a given axis parallel to the central axis P, where the cell structure further has an inner wall 4 on the inner surface of the cavity 3, a method for producing the cell structure, and a catalyst structure. The cell structure having the cavity has an excellent isostatic breaking strength and can exhibit proper sealing function in its cavities. Furthermore, a method for producing the cell structure, the catalyst structure, etc. are provided.
    Type: Application
    Filed: March 27, 2003
    Publication date: May 19, 2005
    Applicant: NGK INSULATORS, LTD
    Inventors: Yukihito Ichikawa, Makoto Miyazaki, Yasushi Kato
  • Publication number: 20050100486
    Abstract: This is directed to a processing method for carrying a cell structure (1) with a catalytic component. Information about a mass of the cell structure (1) is displayed on the surface thereof prior to the initiation of a carrying process, and in the carrying process, the information is read and the cell structure (1) is carried with an appropriate amount of the catalytic component on the basis of the information. When cell structures are processed for carrying thereon a catalytic component, each cell structure can carry an appropriate amount of the catalytic component in accordance with the mass of the cell structure, even if there is a variation in the masses of the cell structures.
    Type: Application
    Filed: November 16, 2001
    Publication date: May 12, 2005
    Inventors: Yukihito Ichikawa, Eiji Ito
  • Publication number: 20040206061
    Abstract: A honeycomb structure includes partition walls arranged in an X-direction and intersecting partition walls so as to form a plurality of cells extending to an other-end portion from a one-end portion through an axial direction. There are disclosed a honeycomb structure in which intersecting portions of the partition walls include an intersecting portion (lacking portion) lacking in the one-end portion, a method of manufacturing the honeycomb structure, and a discharge fluid purification system comprising the honeycomb structure. The honeycomb structure is able to inhibit the opening from being blocked and is easily manufactured.
    Type: Application
    Filed: April 5, 2004
    Publication date: October 21, 2004
    Applicant: NGK INSULATORS, LTD.
    Inventor: Yukihito Ichikawa
  • Publication number: 20040206044
    Abstract: There are provided a honeycomb structure capable, of suppressing a decrease in isostatic strength attendant on the thinning of the honeycomb structure, a honeycomb structure converter thereof, and a method of manufacturing the honeycomb structure. There is provided a honeycomb structure 1 having a number of cells 3 partitioned by partition walls 2 and extending to a axial direction. There are the honeycomb structure wherein a thickness (TY) of a partition walls (2Y) whose longitudinal direction is one direction (Y-direction) in a section perpendicular to the axial direction of the honeycomb structure 1 is greater than that (TX) of a partition walls (2X) whose longitudinal direction is the other direction; and a honeycomb structure converter thereof. There is provided a method of molding the above-mentioned honeycomb structure. That is the method of molding honeycomb structure wherein the honeycomb structure is extrusion molded such that the Y-direction is a direction of gravity.
    Type: Application
    Filed: February 19, 2004
    Publication date: October 21, 2004
    Applicant: NGK Insulators, LTD
    Inventors: Takahiro Kondo, Yukihito Ichikawa
  • Publication number: 20040209039
    Abstract: A honeycomb structure includes partition walls arranged so as to form a plurality of cells extending to an other-end portion from a one-end portion through an axial direction. There are provided a honeycomb structure including a partition wall having a different height in the axial direction in the one-end portion, and a manufacturing method suitable for the structure. There is provided a honeycomb structure comprising: a plurality of partition walls arranged so as to form a plurality of cells extending through an axial direction; and a plugging portion in an open end portion of a predetermined cell. The honeycomb structure includes convex and concave plugging portions, and intersecting portions of surrounding partition walls of one cell which does not any plugging portion contact one or more cells including the convex plugging portions and one or more cells including the concave plugging portions for each intersecting portion. A manufacturing method suitable for this honeycomb structure is also provided.
    Type: Application
    Filed: April 2, 2004
    Publication date: October 21, 2004
    Applicant: NGK INSULATORS, LTD.
    Inventor: Yukihito Ichikawa
  • Publication number: 20040206062
    Abstract: There are disclosed a honeycomb structure which is preferably usable as a filter, for example, for trapping particulates in an exhaust gas of an internal combustion engine, boiler or the like or for filtering liquids such as city water and sewage and in which an increase of a pressure loss at a use time is inhibited. A honeycomb structure 1 comprises: two end surfaces 5 consisting of first and second end surfaces; a porous body 2 in which a plurality of fluid channels 3 extending to a second end surface 5b from a first end surface 5a are formed; and plugging members 4 for plugging end portions 6 on end surfaces 5 side of the fluid channels 3.
    Type: Application
    Filed: April 7, 2004
    Publication date: October 21, 2004
    Applicant: NGK INSULATORS, LTD.
    Inventor: Yukihito Ichikawa
  • Publication number: 20040187561
    Abstract: There is disclosed a method in which the water absorption of the porous cell structure is measured as the standard for setting the carrying conditions of the catalyst component in advance, when allowing the porous cell structure for use as a catalyst carrier to carry the catalyst component and forming a catalyst layer by a wash coating process. In the present method, an amount of a particulate material sticking to a surface of a partition wall constituting a cell of the porous cell structure and the surfaces of pores in the partition wall is regarded as the water absorption of the porous cell structure to measure the sticking amount.
    Type: Application
    Filed: March 18, 2004
    Publication date: September 30, 2004
    Applicant: NGK INSULATORS, LTD
    Inventor: Yukihito Ichikawa
  • Publication number: 20040177600
    Abstract: A honeycomb structure comprising porous partition walls disposed so as to form a plurality of cells extending in an axial direction. In the honeycomb structure, defining that a porosity and pore diameter of the partition walls in a central portion is (Pi) and (Di), a porosity and pore diameter of the partition walls in an outer peripheral portion is (Po) and (Do), (Pi) and (Po) have a relation of (Pi<Po); or (Pi) and (Po) have a relation of (Pi>Po) and (Di) and (Do) have a relation of (Di<Do).
    Type: Application
    Filed: February 20, 2004
    Publication date: September 16, 2004
    Applicant: NGK INSULATORS, LTD.
    Inventors: Yukihito Ichikawa, Tatsuyuki Kuki
  • Publication number: 20040170803
    Abstract: A honeycomb structural body having a plurality of cells and partition walls defining the cells, wherein a cross-section of each partition wall perpendicular to the flow direction of a fluid to be permeated has a grille shape of which gratings cross in x axis and Y axis directions, and there are at least two kinds of cells different in their cross-sectional areas perpendicular to the flow direction of a fluid to be filtered by virtue of changing intervals of the partition walls in the x axis direction and/or intervals of the partition walls in the y axis direction, as predetermined. Each cell is defined by two parallel partition walls having the same length and another two parallel partition walls having the same length crossing each other and being formed at the predetermined intervals. A die usable for forming such a honeycomb structure is also disclosed.
    Type: Application
    Filed: February 24, 2004
    Publication date: September 2, 2004
    Applicant: NGK INSULATORS, LTD.
    Inventor: Yukihito Ichikawa
  • Publication number: 20040161373
    Abstract: A honeycomb filter comprises a honeycomb structure having a large number of through channels formed in the axial direction and partitioned by porous partition walls, wherein specified through channels are plugged only on one end face at the same side out of two end faces. This honeycomb filter shows less pressure loss, and is hardly clogged with solids that cannot be extinguished by combustion such as ash, iron oxide, and the like. Furthermore, an unwanted discharge of particulates deposited in through channels of the filter in a larger amount due to pulsation even under conditions that the exhaust gas from an engine greatly pulsates can be effectively suppressed. This filter is also usable as an element for exhaust gas purification system, or a part of composite filter in addition to the use for an exhaust gas purification filter for gasoline engines. The production method therefor is also disclosed.
    Type: Application
    Filed: February 17, 2004
    Publication date: August 19, 2004
    Applicant: NGK INSULATORS, LTD.
    Inventors: Yukihito Ichikawa, Toshio Yamada
  • Publication number: 20040123573
    Abstract: A honeycomb structure in which a plurality of through-holes 3 extending in the axial direction are formed by a plurality of partition walls 1 and 2, wherein the plurality of partition walls 1 and 2 are constituted by a plurality of partition walls having different thicknesses and, of the plurality of partition walls having different thicknesses, those partition walls 2 having a thickness larger than the average thickness of all partition walls are provided at a higher proportion in a particular portion of the honeycomb structure whole portion having partition walls than in other portion. This honeycomb structure, and a honeycomb filter and a converter system both using the honeycomb structure satisfy recent years' requirements of improvement in warm-up property connected with purification ability and reduction in harmful substance emitted right after engine start, and yet have a sufficient mechanical strength to external pressure, a high erosion resistance and a high thermal shock resistance.
    Type: Application
    Filed: October 21, 2003
    Publication date: July 1, 2004
    Inventors: Yukihito Ichikawa, Yasushi Kato, Masato Ogawa