METHOD OF DISCHARGING EXHAUST GASES IN TWO-STROKE INTERNAL COMBUSTION ENGINE AND SILENCER Russian patent published in 1997 - IPC

FIELD: engine engineering. SUBSTANCE: method comprises generating the initial compression wave in the flow of exhaust gases which outflow from an engine when outlet port is fully open. A portion of the wave is converted into a rarefaction wave and returns to the cylinder of the engine before closing the blowing ports. A portion of the wave is converted into the reflected compression wave that returns to the cylinder of the engine before closing the outlet port. A portion of the exhaust gas is silenced. In the zone where compression in the initial wave is a maximum a portion of the wave is converted to obtain an additional rarefaction wave and is directed to the cylinder of the engine. The reflected compression wave is generated when the piston is in the bottom dead center. Exhaust gas is fed for silencing in discrete portions together with the reflection wave and rarefaction waves when they return to the cylinder of the engine. The discrete portions are converted into the rarefaction waves which is directed tangentially to the central pipe. The silencer has cylindrical housing with the inlet and outlet branch pipes, central pipe, expansion chamber made up as a trancated cone and a row of perforated baffles between the housing and the central pipe. The silencer is provided with a chamber for generating reflected wave that is made up as a cone diverging in the direction of flow of exhaust gases, the cone being mounted at the rear end of the central pipe, and the outlet radial slot of additional rarefaction of exhaust gases provided over periphery of the inlet branch pipe at the site where expansion chamber is mounted. The side of the first baffle downstream from the inlet branch pipe that does not face the outlet radial slot is perforated. Each subsequent baffle is perforated from the side that does not face the perforation provided on the previous one. EFFECT: enhanced silencing. 3 cl, 3 dwg