Pipe assembly for efficient light-off of catalytic converter
US5390494A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 27, 1993 |
| Grant date | Feb 21, 1995 |
| Priority date | — |
| Expiry date | Apr 27, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49398
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
An exhaust pipe assembly is provided for achieving a quick light-off of a catalytic converter. Exhaust pipe assembly comprises circuitously bent inner and outer pipes disposed in generally concentric relationship to one another. The inner pipe is formed from a very thin metal to provide a low thermal mass and a correspondingly low heat dissipation therefrom. The outer pipe is thicker to provide structural support, and defines an air insulation barrier around the inner pipe to further reduce heat dissipation. The inner pipe is corrugated at selected locations that will correspond to bends in the circuitous exhaust pipe assembly. The thin-walled locally corrugated inner pipe is then inserted into the outer pipe, and the assembly is bent into the required configuration. The corrugations support the inner and outer pipe relative to one another during the bending process and during use. The bent pipe assembly then is connected to the catalytic converter for subsequent mounting to vehicle engine.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.