Engine with two wave barrel cam having dwell periods between rise and return and return and rise profiles

摘要

The invention relates to a Two Wave Barrel Cam profile of a Two Cycle Double Acting Barrel Cam Engine of the Hermann type. Whereby, the normal rise-return-rise-return barrel cam arrangement is modified to a rise-dwell-return-dwell-rise-dwell-return cam profile (See Fig. 4). Pistons connected to the cam follower, can dwell for a longer period of time at top dead centre (TDC) and bottom dead centre (BDC). This arrangement provides an increased duration of constant volume combustion, than a rod and crank mechanism at TDC for either Two or Four cycle engine types. This arrangement also increases the period of time at BDC, thereby increasing the inlet port area opening period. Conveniently, this longer dwell duration at BDC, achieves more inlet port area than is required. This can be corrected for adequate inlet air flow into the cylinder by reducing the height of the port. This advantage allows a later exhaust port opening and closing, providing a greater expansion stroke and improved thermal efficiency.