Muffler assembly

In a muffler:

• a housing having a longitudinal axis and first and second end caps;
• a plurality of partitions dividing said housing into a first expansion chamber adjacent said first end cap, a flow chamber adjacent said first expansion chamber, a resonator chamber adjacent said flow chamber, and a second expansion chamber between said resonator chamber and said second end cap;
• inlet means comprising a first tubular member extending through said first end cap and two of said partitions to project and open into said resonator chamber, said inlet means being laterally apertured at a first site to give communication to said first expansion chamber and at a second site to enable restricted gas flow into said flow chamber;
• and
• outlet means comprising a second tubular member extending through said second end cap and two of said partitions to open into said flow chamber, said outlet means being laterally apertured at a first site to give communication to said second expansion chamber;
• said partition between said flow chamber and said resonator chamber being apertured to enable limited flow of gas from said inlet means through said resonator chamber into said flow chamber, and the ratio of the area of the opening of said inlet means into said resonator chamber to the apertured area of said partition being between 2-to-1 and 4-to-1.

A muffler for reducing the noise level of gases passing therethrough, comprising:

• a housing defining an interior space and having an inlet and an outlet;
• an inlet conduit in fluid communication with said inlet and extending a distance within said interior space for guiding gases into the muffler;
• an outlet conduit in fluid communication with said outlet and extending a distance within said interior space for guiding gases out of the muffler;
• partition means for dividing said interior space into a resonator chamber, a flow chamber, and at least one expansion chamber;
• said inlet conduit having an open end disposed within said resonator chamber and a plurality of flow holes through it for providing fluid communication between said inlet and said flow chamber;
• said outlet conduit having an open end disposed within said flow chamber for guiding gas from said flow chamber to said outlet;
• means enabling limited flow of gas through said resonator chamber;
• and
• at least one of said inlet and outlet conduits having a plurality of attenuation holes through it for providing fluid communication to said at least one expansion chamber so that broad band sound attenuation can occur therein.

A muffler for reducing the noise level of gases passing therethrough, comprising:

• (a) a housing defining an interior space and having an inlet and an outlet;
• (b) means in said housing for dividing said interior space into a resonator chamber, a flow chamber, and at least one expansion chamber;
• (c) means defining a gas flow path between said inlet and said outlet, comprising:
• (i) inlet conduit means in fluid communication with said inlet and extending a distance within said interior space for guiding gases into the muffler;
• (ii) an outlet conduit in fluid communication with said outlet and extending a distance within said interior space for guiding gases out of the muffler;
• (iii) said inlet conduit means having an open end disposed within said resonator chamber and having means providing fluid communication between said inlet and said flow chamber;
• (iv) said outlet conduit having an opening disposed within said flow chamber for guiding gas from said flow chamber to said outlet;
• (d) means including aperture means between said resonator chamber and said gas flow path enabling limited flow of gas through said resonator chamber, the ratio of the area of the open end of said inlet means into said resonator chamber to the aperture means being between 2-to-1 and 4-to-1;
• and
• (e) at least one of said inlet and outlet conduits having a plurality of attenuation holes through it for providing fluid communication to said at least one expansion chamber so that broad band sound attenuation can occur therein.