Gas discharge apparatus

An exhaust gas muffler apparatus, comprising:

• exhaust gas intake means for receiving hot exhaust gases from an engine;
• an expansion chamber communicating with said exhaust gas intake means and including a first wall member having at least one aperture therein;
• an exhaust expansion chamber including an exhaust gas outlet tube for exhausting cooled exhaust gases to the atmosphere;
• a plurality of first elongated channels each having a first inlet and a first outlet and extending between said first wall member and a first region adjacent said exhaust expansion chamber, the first inlets being interconnected with said at least one aperture and each of the first outlets opening into said first region, and said plurality of first elongated channels having at least one outer wall member exposed to the atmosphere;
• at least one second elongated channel having a common wall with respective walls of said plurality of first elongated channels and a second inlet and second outlet, said second inlet being interconnected with the first outlets, and said second outlets opening into a second region adjacent said wall member;
• an exhaust gas tube extending between said exhaust expansion chamber and said first region and having a wall member common to said second elongated channel;
• and
• a plurality of fins extending from the common wall of said elongated second channel through said at least one outer wall member into the atmosphere, said plurality of fins together with said at least one outer wall member and the common wall of said elongated second channel, forming said plurality of first elongated channels.