Rotary power unit

A rotary engine including, a housing having a casing provided with a tri-lobular interior wall, a substantially elliptical piston disposed within said casing and having two curved faces terminating to provide a nose at the two distal portions of the major axis of said piston, planar side faces on said piston, said major axis of a greater length than a chord subtending any two adjacent lobes of said tri-lobular casing interior wall, said housing including two side plates having planar inner faces enclosing said piston and casing interior wall, said piston provided with a central bore bounded by a circular bearing surface, a female piston position gear formed on each side of said piston bearing surface, a center drive cam journaled within said piston bore, each said side plate including a central opening having a surrounding circular female bearing surface adjacent said piston sidewall and a cam drive outer gear outside said female bearing surface, support means including a cylindrical head journaled in each said female bearing surface and each having a planar inner face coplanar with said respective side plate face, said drive cam including integral eccentric end drive means extending laterally from both sides thereof and projecting respectively through each said support means, an eccentrically disposed male piston position gear on each said support means each journaled about one said end drive means and engaging one said female piston position gear, a cam drive inner gear carried by the projecting portion of each said end drive means on the side of said support means away from said piston and engaging said cam drive outer gear, three firing chambers defined between said casing interior wall and one of said piston faces adjacent said casing lobes, said male and female piston position gears defining a ratio of 1:2 whereby, as said piston rotates 60.degree. from one firing chamber to another the center axis thereof is displaced 120.degree. relative said side plate openings.