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Engine Assembly System Description - Atkinson Cycle

The Atkinson Cycle engine has a bigger expansion ratio than its compression ratio compared to the conventional Otto Cycle engine. In addition to the intake, compression, combustion, and exhaust strokes found in the conventional engine, the Atkinson Cycle engine has a back-flow process, which takes place after the intake allowing the air-fuel mixture in the cylinders to flow back into the intake manifold by delaying the timing of closing the intake valve. Having the bigger expansion ratio than the compression ratio, allows the engine to convert more heat energy into kinetic energy. Allowing the air-fuel mixture to flow back into the intake manifold lowers the compression ratio, resulting in the reduction of pumping loss as well. The combination of above features contributes to the improvement of the fuel economy.

GHH259406Courtesy of HONDA, U.S.A., INC.

Operations of different processes 

GHH259407Courtesy of HONDA, U.S.A., INC.