Active exhaust-noise attenuation muffler
US5574264A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 9, 1994 |
| Grant date | Nov 12, 1996 |
| Priority date | — |
| Expiry date | Aug 9, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K2210/509
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
An electronically controlled active exhaust-noise attenuation muffler, comprises a loudspeaker serving as a secondary sound source arranged upstream of a tailpipe and communicating with an interior of an exhaust pipe, for attenuating a noise level of exhaust noise produced by the exhaust system by emitting a secondary sound, which is in opposite phase to the exhaust noise, into the exhaust pipe. The tailpipe is formed in a flared-out fashion so that a cross-sectional area of the tailpipe gradually increases towards a downstream end thereof, to reduce pressure loss in exhaust gas flow in the exhaust pipe by radiating the exhaust gas through the flared-out tailpipe. The tailpipe section is a high-frequency exhaust noise attenuation structure to attenuate a high-frequency noise component propagated with a moving stream of the exhaust gases.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.