A rotary internal combustion engine having the four phases of intake, compression, expansion and exhaust with each revolution of the engine shaft, the engine comprising:
- a stator with a cylinder bore sealed between parallel end walls;
- a power shaft concentric with the cylinder bore supported in bearings in the end walls;
- an eccentric rotor fixed to the power shaft, virtually coextensive with the end walls, its head barely clearing the cylinder, each of the rotor ends fitted with yieldable seals to sweep the end walls;
- a transverse wiper blade in a slot across the rotor head, spring biased outward to yieldably sweep the face of the cylinder to form a suction stroke behind it and a compression stroke ahead of it as the rotor travels, to suck air into the cylinder through a port in the lower part of the stator and at the same time to force air ahead of it into a combustion chamber;
- an air inlet port centered between 5:00 and 7:00 o'clock, comprising an opening in the stator fitted with one-way inlet valves, to allow air to be sucked into the cylinder but prevent it from being pumped out via the inlet port;
- an abutment comprising a rectangular metal base plate turned upward at one end to form an "L", the base plate rounded at its other end to form a pivot and the pivot cradled in a shallow seat in the cylinder near 2:00 o'clock, the shallow seat allowing the abutment to oscillate vertically inside the cylinder space as its base plate rides on the eccentric rotor;
- the base plate reaching counter-clockwise from its pivoted end somewhat further than a vertical line through the center of the engine shaft;
- the upward extension of the abutment in the shape of an arc with the pivot as its center;
- the abutment fitted with one-way valves to allow compressed air to pass through from the cylinder during a compression stroke to be trapped in a combustion chamber inside the elbow of the abutment, between the abutment base plate and the stator;
- the abutment spring biased downward toward the rotor by a spring outside at least one end wall, the spring bearing against an arm which is fixed to a hub on the end of the abutment pivot extending through the end wall, the pivot to transmit the downward thrust of the spring to the abutment with which it is integral;
- the abutment fitted with at least one end seal in a slot, on each end, to sweep the end walls to prevent combustion gases from leaking out of the combustion chamber between the end walls and the ends of the abutment;
- a combustion-expansion chamber of variable cubic volume, roughly triangular in shape as viewed from an end, contained inside the abutment elbow, the chamber formed by the abutment base plate as one side, the arcuate abutment extension as the second side and the compression head area of the stator as the third side, the chamber closed on its ends by the end walls between which the abutment is caused to slidably oscillate, the compression head so positioned in the engine casting that when the abutment is at its zenith a combustion chamber of predetermined minimum cubic volume is formed;
- an arcuate channel cast in the stator on a radius from the pivot, the channel so positioned and of such dimensions as to receive the abutment extension in a close-fitting cavity on the upward swing of the abutment, to allow the abutment base plate to squeeze a charge of air upward against the compression head;
- a fuel injector projecting into the combustion chamber to spray a charge of fuel into the compressed air in the chamber as the rotor head approaches top center, and a glow plug projecting into the same chamber in close proximity to the fuel injector to aid in igniting the fuel charge, the gases of combustion to bear downward on the base plate to cause the eccentric rotor to rotate;
- roller bearings on the under side of the abutment base plate positioned to bear on the rotor through the expansion stroke to minimize friction in transferring power from the abutment to the rotor;
- primary exhaust means comprising a horizontal slot through the stator near the base of the arcuate channel, on a level with the under side of the compression head, the slot covered by the arcuate extension of the abutment during the compression and expansion strokes but uncovered by that abutment extension as it drops out of its channel at the end of the expansion stroke, the slot allowing compressed air forced into the expansion chamber ahead of the rotor to sweep spent gases out of the engine;
- auxiliary exhaust means comprising a slot in the outer end of the arcuate channel which slot is shut off during the compression and expansion strokes by the abutment extension but is uncovered at the end of the expansion stroke when the abutment extension drops out of its channel, allowing the spent gases to flow from the expansion chamber up through the channel and out via the slot;
- the forward face of the rotor somewhat flattened for a span of sixty to ninety degrees, the flattened span beginning a few degrees ahead of the wiper blade, the flattening designed to let the rotor pump virtually all the air out of the cylinder into the combustion chamber before the curvature of the rotor lifts the abutment too far into the stator space to allow the abutment inlet valves to function;
- means for cooling and at the same time lubricating the rotor, its bearings and the rotor end seals, the means comprising an oil conduit through the engine shaft on a first end of the engine, the conduit opening into the space between the rotor web and the first end wall, bores through the rotor web to the opposite side, an opening on that side into the engine shaft and a conduit through the shaft out through the second end of the engine.