Rotary mower engine muffler

Claim 1

A ROTARY MOWER HAVING A HOUSING INCLUDING DOWNWARDLY EXTENDING AND GENERALLY CONCENTRIC CIRCULAR, INNER AND OUTER WALLS WHICH TOGETHER DEFINE AN ANNULAR TUNNEL FOR THE CONFINEMENT AND PASSAGE OF CLIPPING FOR ULTIMATE DISCHARGE FROM THE MOWER; SAID TUNNEL BEING OF A RELATIVELY SMALL CROSS SECTION AT ITS BEGINNING END AND INCREASING IN CROSS SECTION TOWARDS ITS DISCHARGE END, SAID INNER WALL TERMINATING IN A LOWER EDGE THAT IS APPROXIMATELY HALF-WAY BELOW THE HEIGHT OF SAID HOUSING; SAID HOUSING ALSO HAVING A CENTRAL, DOWNWARDLY EXTENDING AND FLAT DISH-SHAPED PORTION WHICH TERMINATES IN A LOWER EDGE THAT DEFINES A CENTRAL OPENING; SAID DISH-SHAPED PORTION HAVING A DIAMETER THAT IS GREATER THAN ONE-HALF THE DIAMETER OF SAID CIRCULAR INNER WALL, SAID PORTION HAVING A HEIGHT LESS THAN ONE-HALF OF THE HEIGHT OF SAID HOUSING A GENERALLY FLAT AND INVERTED DISH-SHAPED COVER SECURED BETWEEN AND TO THE LOWER EDGES OF SAID INNER WALL AND PORTION TO THEREBY DEFINE A MUFFLER CHAMBER WITH SAID INNER WALL DISH-SHAPED PORTION, AN ENGINE BASE SECURED ON TOP OF SAID HOUSING SO AS TO DEFINE WITH SAID PORTION A SUBSTANTIALLY ENCLOSED SPACE FOR INSULATING AN ENGINE CARRIED ON SAID BASE FROM SAID PORTION, AN EXHAUST PASSAGE FROM SAID ENGINE AND IN COMMUNICATION WITH SAID CHAMBER, AND APERTURES IN SAID COVER PLACING SAID CHAMBER IN EXHAUST DISCHARGING COMMUNICATION WITH THE SMALL BEGINNING END OF SAID TUNNEL.