METHOD OF GAS EXCHANGE IN TWO-STROKE ICE Russian patent published in 2013 - IPC F02B25/00 

FIELD: engines and pumps.

SUBSTANCE: combustion products are vented from cylinder cavity via openings released by the piston and directed into atmosphere via exhaust manifold. Then, fresh charge is used to scavenge and to fill the cylinder after charge gas pressure exceeds that in exhaust manifold. Note here that in scavenging, a portion of fresh charge is directed into cylinder cavity via exhaust manifold while another portion of fresh charge is directed right after combustion products into exhaust manifold at filling the part of exhaust manifold with fresh charge. Then, exhaust manifold cross-section is shut off by slide valve timed with piston displacement to bar combustion products motion to increase pressure in exhaust manifold upstream of slide valve in gas escape path. Increased gas pressure ahead of slide valve displaces fresh charge fed to exhaust manifold back toward the cylinder. Fresh charge is forced from exhaust manifolds shutoff by slide valve into cylinder cavity by the energy of combustion products. Thereafter, openings are shut off by the piston at compression stroke start.

EFFECT: higher specific power of two-stroke engine.

6 cl, 7 dwg