초록 ▼

A number of embodiments of an exhaust system for outboard motors that includes a trap portion in a conduit which conveys the exhaust gases from an expansion chamber formed in the drive shaft housing to an underwater exhaust gas discharge. The trap portion has a horizontal section that is disposed ab

A number of embodiments of an exhaust system for outboard motors that includes a trap portion in a conduit which conveys the exhaust gases from an expansion chamber formed in the drive shaft housing to an underwater exhaust gas discharge. The trap portion has a horizontal section that is disposed above the water level, and various orientations are depicted. In addition, a catalyst is also provided, and the catalyst is protected from water also by the construction.

대표청구항 ▼

[ We claim:] [1.] An outboard motor having a power head comprised of an internal combustion engine having an exhaust port and a surrounding protective cowling, a drive shaft housing and lower unit depending from said power head and containing a propulsion device driven by said engine for propelling

[ We claim:] [1.] An outboard motor having a power head comprised of an internal combustion engine having an exhaust port and a surrounding protective cowling, a drive shaft housing and lower unit depending from said power head and containing a propulsion device driven by said engine for propelling associated watercraft, means for affixing said outboard motor to a hull of an associated watercraft for pivotal movement about a horizontally disposed tilt axis, an expansion chamber formed in said drive shaft housing and lower unit and positioned to be at least partially submerged beneath the body of water in which the watercraft is operating at least when the watercraft is stationary, an exhaust pipe extending from said exhaust port into said expansion chamber below the upper end thereof for delivering exhaust gases from said engine to said expansion chamber, an underwater exhaust gas discharge positioned to extend beneath the water level in substantially all running conditions of the watercraft, and exhaust conduit means extending from said expansion chamber to said underwater exhaust gas discharge for delivering exhaust gases from said engine to the atmosphere through the body of water in which said watercraft is operating, said exhaust conduit means including a trap portion for precluding the entry of water into said expansion chamber from said underwater exhaust gas discharge comprised of, a first upwardly extending section extending upwardly from an inlet end in said expansion chamber, a horizontally extending section disposed entirely above the water level and said tilt axis and receiving gases from the upwardly extending section at one end thereof, and a downwardly extending section extending from the other end of said horizontally extending section to said underwater exhaust gas discharge.