Honeycomb structure

Patent metadata

Field	Value
Publication number	US-11396009-B2
Application number	US-201916299708-A
Country	US
Kind code	B2
Filing date	Mar 12, 2019
Priority date	Mar 28, 2018
Publication date	Jul 26, 2022
Grant date	Jul 26, 2022

Abstract

A honeycomb structure including a honeycomb having porous partition walls extending between inflow and outflow end faces to define cells, an outermost peripheral wall, and a pair of electrodes disposed on a side surface of the honeycomb. Each electrode is formed in a strip shape extending in a direction of the cells. In a cross section orthogonal to the extending direction of the cells, one electrode is disposed on a side opposed to the other electrode. The honeycomb has an outer peripheral region including the outer peripheral wall, a central region, and an intermediate region. An average electric resistivity A of a material constituted of the outer peripheral region, an average electric resistivity B of a material constituted of the central region and an average electric resistivity of C of a material constituted of the intermediate region satisfy the relationship: A≤B<C.

First claim

The invention claimed is:

1. A honeycomb structure, comprising:
a pillar shaped honeycomb structure portion having:
porous partition walls extending through the honeycomb structure from an inflow end face to an outflow end face, to define a plurality of cells forming a through channel;
an outer peripheral wall located at the outermost periphery; and

a pair of electrode portions disposed on a side surface of the honeycomb structure portion;
wherein each of the pair of electrode portions is formed in a strip shape extending in an extending direction of the cells of the honeycomb structure portion;
wherein, in a cross section orthogonal to the extending direction of the cells, one electrode portion of the pair of electrode portions is disposed on a side opposed to the other electrode portion across a center of the honeycomb structure portion;
wherein the honeycomb structure portion consists an outer peripheral region including the outer peripheral wall; a central region that is a center area; and an intermediate region excluding the outer peripheral region and the central region; and
wherein an average electric resistivity A of a material constituted of the outer peripheral region, an average electric resistivity B of a material constituted of the central region and an average electric resistivity of C of a material constituted of the intermediate region satisfy the relationship: A≤B<C.

2. The honeycomb structure according to claim 1 , wherein the honeycomb structure satisfies the relationship: A×L1<2/3×L2×(A+B+C), in the cross section orthogonal to the extending direction of the cells,
wherein L1 is a surface circumferential length of the honeycomb structure portion from an end portion of one of the electrode portions to an end portion of the other of the electrode portions, and L2 is the sum of a distance from the end portion of one of the electrode portions to a center of the honeycomb structure portion and a distance from the end portion of the other of the electrode portions to the center of the honeycomb structure portion.

3. The honeycomb structure according to claim 1 , wherein the honeycomb structure portion is mainly based on a silicon-silicon carbide composite material or silicon carbide.

4. The honeycomb structure according to claim 1 , wherein the honeycomb structure portion has an electric resistivity of from 0.1 to 100 Ωcm and the electrode portions have an electric resistivity of from 0.001 to 1.0 Ωcm.

5. The honeycomb structure according to claim 1 , wherein each of the electrode portions has a central angle of from 60 to 120°.

Assignees

• Ngk Insulators Ltd

Inventors

• Takase Naoya

Classifications

• H05B3/148 Primary

  Silicon, e.g. silicon carbide, magnesium silicide, heating transistors or diodes · CPC title

• F01N3/0222 Primary

  the structure being monolithic, e.g. honeycombs · CPC title

• F01N3/2832

  granular, e.g. pellets · CPC title

• H05B2203/024

  Heaters using beehive flow through structures · CPC title

• H05B3/42

  non-flexible · CPC title