Hybrid cycle rotary engine
An internal combustion engine includes in one aspect a source of a pressurized working medium and an expander. The expander has a housing and a piston, movably mounted within and with respect to the housing, to perform one of rotation and reciprocation, each complete rotation or reciprocation defining at least a part of a cycle of the engine. The expander also includes a septum, mounted within the housing and movable with respect to the housing and the piston so as to define in conjunction therewith, over first and second angular ranges of the cycle, a working chamber that is isolated from an intake port and an exhaust port. Combustion occurs at least over the first angular range of the cycle to provide heat to the working medium and so as to increase its pressure. The working chamber over a second angular range of the cycle expands in volume while the piston receives, from the working medium as a result of its increased pressure, a force relative to the housing that causes motion of the piston relative to the housing.
1. An internal combustion engine, comprising:
a housing having an interior region with a generally circular cross section defined by an inner surface of the housing, wherein the generally circular cross section is interrupted by a rocker mounting region, the housing also having a pair of sides;
a cam, rotatably mounted in the housing, that sweeps a circular path in the interior region, the cam in sealing contact with the sides of the housing and also, when a leading edge of the cam is not adjacent to the rocker mounting region, in sealing contact with the inner surface of the housing;
a cam-following rocker, mounted in the rocker mounting region, in sealing contact with the sides of the housing, and, at least when the leading edge of the cam is not adjacent to the rocker mounting region, in sealing contact with the cam, the rocker having a seated position defining generally, when a leading edge of the cam is adjacent to the rocker mounting region, a continuation of the circular cross section of the housing, the rocker pivoted at a pivot end to move at a free end generally radially with respect to the circular path of the cam, so that the free end of the pivot reciprocates between the seated position and a maximum unseated position, completing a full reciprocation cycle when the cam completes a revolution around the working region;
a combustion chamber, defined at least in part by the cam and the housing, and formed in the housing proximate to the rocker mounting region adjacent to the free end of the rocker, and having an opening, such opening being occluded by the cam over a first angular range of rotation of the cam;
an intake port coupled to the combustion chamber for providing pressurized working medium, the working medium including one of (i) an oxygen-containing gas to which fuel is added within or before the first angular range and (ii) an oxygen-containing-gas-fuel mixture;
wherein combustion occurs within the first angular range so as to provide substantially constant volume combustion in the combustion chamber;
the cam and the rocker being configured to provide an expansion region over a second angular range when the arcuate opening is not occluded; and
an exhaust port, formed in the housing proximate to the rocker mounting region adjacent to the free end of the rocker, for removing expended working medium;
wherein the cam provides an output torque relative to the housing resulting from the combustion.