Honeycomb structural body

• US 20060032203A1
• Filed: 06/07/2004
• Published: 02/16/2006
• Est. Priority Date: 06/05/2003
• Status: Active Grant

• Current Assignee: Ibiden Co., Ltd.
• Original Assignee: Ibiden Co., Ltd.
• Inventors: Ohno, Kazushige, Hong, Sungtae, Komori, Teruo, Oshimi, Yukio
• Granted Patent: US 8,246,710 B2
• Time in Patent Office: Days
• US Class Current: 55/523
• CPC Class Codes: B01D 46/2425 characterized by parameters related to the physical properties of the honeycomb structure material
• CPC Class Codes: B01D 46/2429 of the honeycomb walls or cells
• CPC Class Codes: B01D 46/247 of the cells
• CPC Class Codes: B01D 46/2476 Monolithic structures
• CPC Class Codes: B01D 46/2478 Structures comprising honeycomb segments
• CPC Class Codes: B01D 46/2484 Cell density, area or aspect ratio
• CPC Class Codes: B01D 46/2486 characterised by the shapes or configurations
• CPC Class Codes: B01D 46/249 Quadrangular e.g. square or diamond
• CPC Class Codes: B01D 46/2494 Octagonal
• CPC Class Codes: B01D 46/2498 The honeycomb filter being defined by mathematical relationships
• CPC Class Codes: B01D 46/84 by heating only
• CPC Class Codes: F01N 2330/06 Ceramic, e.g. monoliths
• CPC Class Codes: F01N 2330/34 with flow channels of polygonal cross section
• CPC Class Codes: F01N 2330/48 characterised by the number of flow passages, e.g. cell density
• CPC Class Codes: F01N 2350/02 Fitting ceramic monoliths in a metallic housing
• CPC Class Codes: F01N 3/0222 the structure being monolithic, e.g. honeycombs
• CPC Class Codes: F01N 3/2828 Ceramic multi-channel monoliths, e.g. honeycombs
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y10T 428/24149 Honeycomb-like

Abstract

An object of the present invention is to provide a honeycomb structural body with a long service life, which can reduce a pressure loss to a low level upon collecting particulates and maintain the pressure loss at the low level for a long time even after regenerating processes. The honeycomb structural body includes a columnar porous ceramic block in which a large number of through holes are placed in parallel with one another in the length direction with a wall portion interposed therebetween. Herein, the large number of through holes are constituted by a group of large-capacity through holes, each of which is sealed at one end of the honeycomb structural body so that the total sum of the areas on a cross section perpendicular to the length direction is made relatively great, and a group of small-capacity through holes, each of which is sealed at the other end of the honeycomb structural body so that the total sum of the areas on the cross section is made relatively small, and a surface roughness R_y of the wall face of the through hole is set in a range from 10 to 100 μm.

Claims

1. A honeycomb structural body made of a columnar porous ceramic block in which a large number of through holes are placed in parallel with one another in the length direction with a wall portion interposed therebetween,

wherein

said large number of through holes comprises:

a group of large-capacity through holes, each of which is sealed at one end of said honeycomb structural body such that the total sum of the areas thereof on a cross section perpendicular to the length direction is made relatively great; and

a group of small-capacity through holes, each of which is sealed at the other end of said honeycomb structural body such that the total sum of the areas on said cross section is made relatively small,

a surface roughness R_y of the wall face of said through hole being set in a range from 10 to 100 μ

m.

2. The honeycomb structural body according to claim 1,

wherein

a density of the through holes on a cross section perpendicular to the length direction is set in a range from 15.5 to 62 pcs/cm².

3. The honeycomb structural body according to claim 1 or 2,

wherein

the large number of through holes are constituted by two kinds of through holes, that is, large-capacity through holes each of which has a relatively greater area on a cross section perpendicular to the length direction and small-capacity through holes each of which has a relatively smaller area on said cross section perpendicular to the length direction.

4. The honeycomb structural body according to any one of claims 1 to 3,

wherein

the shape of a cross section perpendicular to the length direction of each of the through holes is a polygonal shape.

5. The honeycomb structural body according to any one of claims 1 to 4,

wherein

the shape of a cross section perpendicular to the length direction of each of the through holes is an octagonal shape or a quadrangle shape.

6. The honeycomb structural body according to any one of claims 1 to 5,

wherein

the ratio (group of large-capacity through holes/group of small-capacity through holes) of areas of cross sections of the group of large-capacity through holes to the group of small-capacity through holes is set in a range from 1.01 to 6.

7. The honeycomb structural body according to any one of claims 3 to 6,

wherein

the ratio (large-capacity through holes/small-capacity through holes) of areas of cross sections of the large-capacity through holes to the small-capacity through holes is set in a range from 1.01 to 6.

8. The honeycomb structural body according to any one of claims 3 to 7,

wherein

on the cross section perpendicular to the length direction,

at least one angle at which

a part of a wall portion, shared by one of said large-capacity through holes and an adjacent large-capacity through hole, and

a part of a wall portion, shared by one of said large-capacity through holes and an adjacent small-capacity through hole,

are caused to intersect with each other is set to an obtuse angle.

9. The honeycomb structural body according to any one of claims 3 to 8,

wherein

the vicinity of each of corners on the cross section of the large-capacity through hole and/or the small-capacity through hole is formed by a curved line.

10. The honeycomb structural body according to any one of claims 3 to 9,

wherein

the distance between centers of gravity of cross sections perpendicular to the length direction of adjacently located large-capacity through holes is set to be equal to the distance between centers of gravity of cross sections perpendicular to the length direction of adjacently located small-capacity through holes.

11. The honeycomb structural body according to any one of claims 1 to 10,

wherein

the porous ceramic block is constituted by combining a plurality of columnar porous ceramic members, each having a plurality of through holes that are placed in parallel with one another in the length direction with a partition wall interposed therebetween, with one another through sealing material layers.

12. A filter for use in an exhaust gas purifying device used for a vehicle,

wherein

the honeycomb structural body according to any one of claims 1 to 11 is installed.