Muffler for combustion engines
US4252212A · kind A · utility
Inventor
Key dates
| Filing date | Mar 1, 1979 |
| Grant date | Feb 24, 1981 |
| Priority date | — |
| Expiry date | Mar 1, 1999 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01N1/10
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
The muffler has an inner exhaust gas pipe and an outer casing. The inner pipe has a diameter which expands conically by about 6% between the input to the output ends of the casing. The inner pipe is also provided with longitudinal wall slots measuring about 30 mm by 2 mm and having a lip extending outwards toward the casing. The space between the inner pipe and the casing is filled with stainless steel wool. High frequencies of the vibrations in the exhaust gas are passed through the slots without appreciable gas flow through the slots, and their energy is dissipated in the wool. The wool is held in place by a metal strap wound helically on its edge about the inner pipe and welded to it. The casing is in two split halves which are held together against the inner pipe by a friction clamping element to permit differential expansion between the inner pipe and the casing. Also disclosed is an embodiment in which there are two parallel inner pipes which branch out from a single input connection and then lead to a single output connection.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.