Title:
EXHAUST EMISSION CONTROL DEVICE
Document Type and Number:
Japanese Patent JP3900012
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To dissolve a problem wherein HC to be more discharged after starting cannot be sufficiently purified since separation of HC from an HC absorbent is started before a three way catalyst reaches an activation temperature after cold starting of an engine, in an engine exhaust emission control device using the HC adsorbent.
SOLUTION: A plurality of carriers 21a-21d carrying the HC adsorbent and a catalyst metal are arranged with gaps g1-g3 provided in the direction of a gas flow, and the gap g1 on the upper stream side is increased to a value higher than the gap g2 on the downstream side. Since the gaps (g) shut off transfer of heat between the carriers adjacent to each other in the front and in the rear of the gap and suppress transmission of heat to the downstream, the increase of the temperature of the carrier on the downstream side is delayed, and an HC capture amount is increased and a temperature rising amount is increased and treating efficiency during separation of the HC is improved. Since turbulence of exhaust gas entering the cell of the carrier occurs at gaps and the opportunity of exhaust gas making contact with the HC adsorbent is increased, HC trap performance is improved. Since the magnitudes of the gaps are gradually increased toward the upper stream, the suppression of the heat transfer and the operation of turbulence are activated on an area situated upper stream of the device and HC trap performance and exhaust emission purification performance are sufficiently improved.
Inventors:
Masaaki Ashida
Koichi Mori
Shunichi Mitsuishi
Cormorant Yoshinao
Koichi Mori
Shunichi Mitsuishi
Cormorant Yoshinao
Application Number:
JP2002155201A
Publication Date:
April 04, 2007
Filing Date:
May 29, 2002
Export Citation:
Assignee:
Nissan Motor Co., Ltd
International Classes:
F01N3/24; B01D53/94; F01N3/28; B01J35/04; F01N3/08; F01N3/10; (IPC1-7): F01N3/24; B01D53/94; B01J35/04; F01N3/08; F01N3/10; F01N3/28
Domestic Patent References:
| JP4027706A | ||||
| JP5187228A | ||||
| JP7011944A | ||||
| JP10141047A | ||||
| JP6262088A | ||||
| JP8284646A |
Attorney, Agent or Firm:
Masaki Goto
Yoshio Matsuda
Yoshio Matsuda