Patent attributes
An internal combustion engine of the present invention features separate compression and expansion cycles. The engine includes a separate compressor device which pressurizes air by a ratio greater than 15 to 1, at least one two stroke combustion cylinder and a compressed air conduit for transferring compressed air from the compressor to the at least one combustion cylinder. An air injection valve injects the compressed air into the combustion cylinder during the second half portion of the return stroke of the combustion cylinder. The compressed air is mixed with fuel and combusted for expansion during a power stroke. In this engine compression occurs only to a minor degree in the combustion cylinder. Accordingly, the compression ratio of the present engine may be significantly higher or lower than the volumetric expansion ratio of the combustion cylinder thus resulting in corresponding increases in either power density or thermodynamic efficiency respectively.