Exhaust manifold, for internal combustion engine, for improving durability of oxygen sensor at merging portion of exhaust manifold
US6082103A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 15, 1998 |
| Grant date | Jul 4, 2000 |
| Priority date | — |
| Expiry date | Jun 15, 2018 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01N13/10
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
An exhaust manifold comprising a plurality of exhaust pipes and a merging portion applies exhaust gas from each cylinder uniformly to an oxygen sensor in a merging portion at low speed thereby improving the durability of the oxygen sensor. A downstream forward end of each exhaust pipe of the exhaust manifold, when connected to an inlet wall of a merging case having the oxygen sensor mounted on a side thereof, is formed in the shape of a bell mouth for leading the exhaust gas to the oxygen sensor. Each exhaust pipe is fixedly welded to the merging case at a position upstream of the forward end of the bell mouth. An angle formed by lines perpendicular to tangential lines at starting and ending points of a curved portion of the bell mouth at the forward end of the exhaust pipe is set in the range of 45.degree. to 75.degree.. As a result, the bell mouth spreads over the whole interior of the merging case and reduces a flow rate of the exhaust gas, and part of the exhaust gas flows toward the oxygen sensor. The oxygen sensor is thus more evenly exposed to the exhaust gas and has increased durability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.