Abstract: The present invention relates to a six-stroke internal combustion engine with intake-exhaust valves. All valves in the combustion chamber are named intake-exhaust valves, because said valves function as both intake valves in an intake stroke and exhaust valves in an exhaust stroke. Because in said engine each cycle comprises an intake stroke, a compression stroke, a power stroke, an exhaust stroke, the fifth stroke and the sixth stroke, there is an interval between the exhaust stroke and the intake stroke of the next cycle. Said interval includes strokes five and six. During the exhaust stroke and said interval, all exhaust gases are expelled from a cylinder and cylinder head completely before the intake stroke of the next cycle begins. Utilizing every valve in the combustion chamber as an intake and exhaust valve increases the volumetric efficiency of the engine.

Abstract: The present invention relates to a six-stroke internal combustion engine with intake-exhaust valves. All valves in the combustion chamber are named intake-exhaust valves, because said valves function as both intake valves in an intake stroke and exhaust valves in an exhaust stroke. Because in said engine each cycle comprises an intake stroke, a compression stroke, a power stroke, an exhaust stroke, the fifth stroke and the sixth stroke, there is an interval between the exhaust stroke and the intake stroke of the next cycle. Said interval includes strokes five and six. During the exhaust stroke and said interval, all exhaust gases are expelled from a cylinder and cylinder head completely before the intake stroke of the next cycle begins. Utilizing every valve in the combustion chamber as an intake and exhaust valve increases the volumetric efficiency of the engine.

Abstract: The invention concerns reciprocating piston internal combustion engines and in particular six-stroke type, FIG. 1. In this engine, one cycle comprises an intake stroke, a compression stroke, a power stroke, an exhaust stroke, the fifth stroke and the sixth stroke. In this engine, all combustion chamber valves A, B, C and D FIGS. 1 and 2 function as both intake valves in the intake stroke and exhaust valves in the exhaust stroke. The name of the valves A, B, C and D is intake-exhaust valves or (inlet-outlet valves). Intake ports 1, 2, 3 and 4 and exhaust ports 5, 6, 7 and 8 are connected to each other in the cylinder head 22 of the engine. As a result, fuel-air mixture is drawn into a cylinder 21 via the intake ports 1, 2, 3 and 4 and all combustion chamber valves (intake-exhaust valves) A, B, C and D in the intake stroke and exhaust gases are expelled from the cylinder via the same valves (intake-exhaust valves) and the exhaust ports 5, 6, 7 and 8 in the exhaust stroke.