Rotary internal combustion engine

An internal combustion engine comprising separate rotary compression and expansion sections and a combustion chamber having inlet and outlet ports communicating with said compression and expansion sections respectively, in which each of said compression and expansion sections is a rotary device comprising:

• a first rotor rotatable about a first axis and having at its periphery at least one recess bounded by a curved surface;
• and
• a second rotor counter-rotatable to said first rotor about a second axis, parallel to said first axis, and having at least one radial lobe bounded by a curved surface,
• said rotors intermeshing whereby, on rotation thereof, a transient chamber of progressively increasing (expansion section) or decreasing (compression section) volume is defined between said recesses and lobe surfaces,
• said surfaces being contoured such that during passage of said lobe through said recess, said recess surface is continuously swept, by both a tip of said lobe and a movable location on said lobe which location progresses along both said lobe surface and said recess surface, to define said transient chamber,
• the respective first and second rotors of the compression and expansion sections being coupled for rotation, and
• wherein the inlet and outlet ports of the combustion chamber are valved by adjacent end surfaces of the respective first rotors of the compression and expansion sections, said end surfaces having openings therein communicating with respective recesses of said first rotors.