This invention is a slotted cylindrical rotary valve assembly for an
internal combustion engine, comprising of two sets of gear driven slotted
cylindrical tubes in a cradle apparatus. Each set has two tubes located
co-axially and rotates co-axially, and each tube is slotted to allow for
improved transport of a fuel/air mixture and exhaust. In one embodiment,
an intake set of tubes transport fuel/air through apertures on the tubes.
The exhaust set of tubes transport exhaust through apertures (slots) on
the tubes. The rotation of the tubes brings the apertures in timely
alignment to allow fuel/air injection and exhaust in synchronization with
the cyclical operation of the pistons in the combustion chambers.
Effective sealing in one embodiment is achieved by using a modified
piston with an extension wall extending longitudinally from the top of
the piston to seal intake and exhaust orifices at the top of the chamber.