Honeycomb filter

Patent metadata

Field	Value
Publication number	US-9919255-B2
Application number	US-201514645425-A
Country	US
Kind code	B2
Filing date	Mar 12, 2015
Priority date	Oct 4, 2012
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

A honeycomb filter includes a plurality of honeycomb fired bodies. Each of the plurality of honeycomb fired bodies includes an outer wall, a plurality of cells, and porous cell walls. The plurality of cells include exhaust gas introduction cells each having an open end at an exhaust gas inlet side and a plugged end at an exhaust gas outlet side and exhaust gas emission cells each having an open end at the exhaust gas outlet side and a plugged end at the exhaust gas inlet side. Sub-cells adjacent to the outer wall include exhaust gas introduction sub-cells among the exhaust gas introduction cells and exhaust gas emission sub-cells among the exhaust gas emission cells. A total volume of the exhaust gas emission sub-cells adjacent to the outer wall is greater than a total volume of the exhaust gas introduction sub-cells adjacent to the outer wall.

First claim

What is claimed is:

1. A honeycomb filter comprising:
a plurality of honeycomb fired bodies combined with one another via adhesive layers between the plurality of honeycomb fired bodies, each of the plurality of honeycomb fired bodies comprising:
an outer wall provided on an outer periphery of each of the plurality of honeycomb fired bodies;
a plurality of cells; and
porous cell walls defining the plurality of cells, the plurality of cells including exhaust gas introduction cells each having an open end at an exhaust gas inlet side and a plugged end at an exhaust gas outlet side and exhaust gas emission cells each having an open end at the exhaust gas outlet side and a plugged end at the exhaust gas inlet side, the exhaust gas introduction cells and the exhaust gas emission cells each having a uniform cross-sectional shape throughout from an end at the exhaust gas inlet side to an end at the exhaust gas outlet side except for a plugged portion in a cross section perpendicular to a longitudinal direction of the plurality of cells, each of the exhaust gas emission cells being adjacently surrounded fully by the exhaust gas introduction cells across the porous cell walls except for sub-cells adjacent to the outer wall among the plurality of cells, the sub-cells adjacent to the outer wall comprising exhaust gas introduction sub-cells among the exhaust gas introduction cells and exhaust gas emission sub-cells among the exhaust gas emission cells, a total volume of the exhaust gas emission sub-cells adjacent to the outer wall being greater than a total volume of the exhaust gas introduction sub-cells adjacent to the outer wall.

2. The honeycomb filter according to claim 1 ,
wherein the sub-cells adjacent to the outer wall comprise the exhaust gas introduction sub-cells and the exhaust gas emission sub-cells alternately arranged with the exhaust gas introduction sub-cells, and
wherein a cross-sectional area of each of the exhaust gas emission sub-cells in the cross section perpendicular to the longitudinal direction of the plurality of cells is larger than a cross-sectional area of each of the exhaust gas introduction sub-cells in the cross section perpendicular to the longitudinal direction of the plurality of cells.

3. The honeycomb filter according to claim 1 ,
wherein the exhaust gas introduction cells include first exhaust gas introduction cells and second exhaust gas introduction cells having a larger cross-sectional area than the first exhaust gas introduction cells in the cross section perpendicular to the longitudinal direction of the plurality of cells,
wherein a cross-sectional area of each of the exhaust gas emission cells in the cross section perpendicular to the longitudinal direction of the plurality of cells is equal to or larger than a cross-sectional area of each of the second exhaust gas introduction cells in the cross section perpendicular to the longitudinal direction of the plurality of cells,
wherein, in the cross section perpendicular to the longitudinal direction of the plurality of cells, the exhaust gas introduction cells and the exhaust gas emission cells each have a polygonal shape, and
wherein, in the cross section perpendicular to the longitudinal direction of the plurality of cells,
a side facing one of the exhaust gas emission cells among sides forming a cross-sectional shape of each of the first exhaust gas introduction cells is longer than a side facing one of the exhaust gas emission cells among sides forming a cross-sectional shape of each of the second exhaust gas introduction cells, or
one of sides forming the cross-sectional shape of each of the first exhaust gas introduction cells faces one of the exhaust gas emission cells, and none of sides forming the cross-sectional shape of each of the second exhaust gas introduction cells faces the exhaust gas emission cells.

4. The honeycomb filter according to claim 3 ,
wherein, in the cross section perpendicular to the longitudinal direction of the plurality of cells, the exhaust gas introduction cells and the exhaust gas emission cells each have the polygonal shape, and
wherein, in the cross section perpendicular to the longitudinal direction of the plurality of cells, a side facing one of the exhaust gas emission cells among the sides forming the cross-sectional shape of each of the second exhaust gas introduction cells has a length that is not more than about 0.8 times a length of a side facing one of the exhaust gas emission cells among the sides forming the cross-sectional shape of each of the first exhaust gas introduction cells.

5. The honeycomb filter according to claim 3 ,
wherein, in the cross section perpendicular to the longitudinal direction of the plurality of cells, the exhaust gas emission cells are octagonal, the first exhaust gas introduction cells are square, and the second exhaust gas introduction cells are octagonal.

6. The honeycomb filter according to claim 3 ,
wherein, in the cross section perpendicular to the longitudinal direction of the plurality of cells, the cross-sectional area of each of the second exhaust gas introduction cells is equal to the cross-sectional area of each of the exhaust gas emission cells, and
wherein, in the cross section perpendicular to the longitudinal direction of the plurality of cells, across-sectional area of each of the first exhaust gas introduction cells is about 20% to about 50% of the cross-sectional area of each of the second exhaust gas introduction cells.

7. The honeycomb filter according to claim 5 ,
wherein the porous cell walls separating the plurality of cells of the honeycomb filter have a uniform thickness throughout the porous cell walls.

8. The honeycomb filter according to claim 5 ,
wherein, in the cross section perpendicular to the longitudinal direction of the plurality of cells, the exhaust gas emission cells each have an octagonal cross section, the first exhaust gas introduction cells each have a square cross section, and the second exhaust gas introduction cells each have an octagonal cross section,
wherein, in the cross section perpendicular to the longitudinal direction of the plurality of cells, the cross-sectional shape of each of the second exhaust gas introduction cells is congruent with a cross-sectional shape of each of the exhaust gas emission cells,
wherein, in the cross section perpendicular to the longitudinal direction of the plurality of cells, the exhaust gas emission cells, the first exhaust gas introduction cells, and the second exhaust gas introduction cells are arranged in a manner that
the exhaust gas emission cells are each surrounded by four first exhaust gas introduction cells among the first exhaust gas introduction cells and four second exhaust gas introduction cells among the second exhaust gas introduction cells, which are alternately arranged, across the porous cell walls,
provided that hypothetical segments are drawn which connect a centroid of each octagonal cross section of the four second exhaust gas introduction cells surrounding a reference exhaust gas emission cell among the exhaust gas emission cells, then an intersection of two hypothetical segments among the hypothetical segments intersecting a shape region corresponding to the cross-sectional shape of the reference exhaust gas emission cell coincides with a centroid of the octagonal cross section of the reference exhaust gas emission cell, and
four hypothetical segments among the hypothetical segments that do not intersect the shape region corresponding to the cross-sectional shape of the reference exhaust gas emission cell form a square, and a midpoint of each side of the square coincides with a centroid of each square cross section of the four first exhaust gas introduction cells surrounding th

Assignees

• Ibiden Co Ltd

Inventors

• Shibata Toshiaki
• Miwa Yuki

Classifications

• C04B35/00

  Shaped ceramic products characterised by their composition {(porous ceramic products C04B38/00; ceramic articles characterised by particular shape, see the relevant classes, e.g. linings for casting ladles, tundishes, cups or the like B22D41/02; ceramic substrates for microelectronic semi-conductors H10W70/692)}; Ceramics compositions ({shaping of ceramics B28B;} containing free metal bonded to carbides, diamond, oxides, borides, nitrides, silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides or sulfides other than as macroscopic reinforcing agents C22C); Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products {(infiltration of sintered ceramic preforms with molten metal C04B41/51; chemical preparation of powders of inorganic compounds C01)} · CPC title

• C04B38/00 Primary

  Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof (treating slag with gases or gas generating material C04B5/06 {; expanded graphite C04B35/536}) · CPC title

• B01D39/2068

  Other inorganic materials, e.g. ceramics · CPC title

• C04B2111/00793

  as filters or diaphragms · CPC title

• B01D2046/2437

  Operations & Transport · mapped topic