Muffler for an internal combustion engine

Abstract

A muffler for an internal combustion engine or the like having improved attenuation, minimal back pressure and minimal effect to column inertia through the muffler. The muffler comprises an outer housing and a first perforated tube insert extending from one end of the housing and terminating within the muffler. In another embodiment the perforated first tube includes a second tube insert abutting the distal end of the first tube in a continuous flow relationship therewith. The second tube has a smaller diameter than the first tube and includes at least one enlarged portion between its ends. Other embodiments are shown that include a combination of either the first and second tubes alone, a second tube with a plurality of enlarged portions between its ends, different sized enlarged portions between the ends of the second tube, various configured enlarged portions and at least two different sized perforations through the perforated tubes. A bracket is shown for attaching the tubes within the housing.

Dependencies are inferred from the claim text.