US Patent 9644509 Muffler

The present invention in one or more embodiments provides a muffler, where the muffler includes a housing extending along a longitudinal direction, and a resonator device supported on the housing and including a body, the body including a first portion and a second portion spaced apart from and to be in fluid communication with the first portion, the fluid communication being positioned in a direction transverse to the longitudinal direction, at least one of the first portion and second portion being of a closed-loop in cross-section. The muffler of the present invention may effectively enhance reduction of low frequency noise without having to necessarily increase package volume.