Electrically heated catalyst

Patent metadata

Field	Value
Publication number	US-10100691-B2
Application number	US-201715423867-A
Country	US
Kind code	B2
Filing date	Feb 3, 2017
Priority date	Feb 5, 2016
Publication date	Oct 16, 2018
Grant date	Oct 16, 2018

Abstract

In an EHC, a ratio of a heat capacity of the second catalyst body with respect to a heat capacity of the first catalyst body is made within a range of 0.67-1.5. A ratio of an amount of coat of an OSC material in the second catalyst body with respect to an amount of coat of an OSC material in the first catalyst body is made larger than the ratio of the heat capacity of the second catalyst body with respect to the heat capacity of the first catalyst body. A ratio of an amount of support of a noble metal in the second catalyst body with respect to an amount of support of a noble metal in the first catalyst body is made smaller than the ratio of the heat capacity of the second catalyst body with respect to the heat capacity of the first catalyst body.

First claim

What is claimed is:

1. An electrically heated catalyst which is arranged in an exhaust passage of an internal combustion engine, and in which a first catalyst body and a second catalyst body, each of which is formed by coating on a substrate an OSC material which is a coating material having an oxygen retaining capacity, and by supporting a noble metal on the substrate, are received in the same case, in which said second catalyst body is arranged at the downstream side of said first catalyst body and the substrate of said first catalyst body is electrically energized to generate heat,
wherein a ratio of a heat capacity of said second catalyst body with respect to a heat capacity of said first catalyst body is within a range of 0.67-1.5;
a ratio of an amount of coat of the OSC material in said second catalyst body with respect to an amount of coat of the OSC material in said first catalyst body is larger than the ratio of the heat capacity of said second catalyst body with respect to the heat capacity of said first catalyst body; and
a ratio of an amount of support of the noble metal in said second catalyst body with respect to an amount of support of the noble metal in said first catalyst body is smaller than the ratio of the heat capacity of said second catalyst body with respect to the heat capacity of said first catalyst body.

2. The electrically heated catalyst as set forth in claim 1 , wherein
the ratio of the amount of coat of the OSC material in said second catalyst body with respect to the amount of coat of the OSC material in said first catalyst body is within a range of 1.2-3.

3. The electrically heated catalyst as set forth in claim 1 , wherein
the ratio of the amount of support of the noble metal in said second catalyst body with respect to the amount of support of the noble metal in said first catalyst body is within a range of 0.4-0.8.

4. The electrically heated catalyst as set forth in claim 2 , wherein
the ratio of the amount of support of the noble metal in said second catalyst body with respect to the amount of support of the noble metal in said first catalyst body is within a range of 0.4-0.8.

Assignees

• Toyota Motor Co Ltd

Inventors

• Tsurumi Kazuki
• Tanaka Hiroshi
• Hirooka Shigemasa
• Korenaga Shingo

Classifications

• B01D53/9477

  with catalysts positioned on separate bricks, e.g. exhaust systems · CPC title

• B01D2255/2092

  Aluminium · CPC title

• B01D2255/904

  Multiple catalysts · CPC title

• B01D2255/1021

  Platinum · CPC title

• F01N13/0097

  the purifying devices are arranged in a single housing · CPC title