Abstract:
This invention relates to improving the internal combustion in reciprocating engines of 4 or 2 cycle operation, and more particularly to reciprocating engines which are compounded in order to provide extension of the expansion event. Both primary cylinders and larger secondary cylinders have pistons moving in block cylinders that are cooled and lubricated as usual, but added cylinders are fastened on the top of each block cylinder, each of the same bore and axially aligned with the block cylinder below them, their length that of the stroke of their piston. At the top of each piston's stroke, the piston is in the block cylinder as usual with rings in the normal place, but above the block, the piston extends toward the head, slightly smaller, and concentric with the lower part, a distance for the right compression ratio. This space between the piston and cylinder allows both to operate at high temperatures, but not touch each other, so no lubrication is needed. Each primary cylinder, with its piston and the head, form a space where compression, combustion and expansion occur. The added cylinder and upper end of its piston are not cooled and operate perhaps red hot, and both can stand high temperatures. The secondary cylinder and piston are made the same way, so they operate hot, but no fuel is added. This allows combustion to occur in both cylinders with very limited loss of heat and near complete expansion of the working fluid, for more power with the same amount of fuel, and less pollution.