Internal combustion engine with two intake and two exhaust valves

Claim 1

In an internal combustion engine having two intake valves and two exhaust valves for each cylinder, said intake and exhaust valves being arranged in a suspended array, one of said intake valves and one of said exhaust valves being opposite one another in relation to the cylinder axis, the axis of a first of said intake valves being located approximately on a longitudinal median plane of the internal combustion engine, the axis of a second of said intake valves being located on a transverse plane of the engine approximately normal to the longitudinal median plane and including the cylinder axis, a first inlet port originating at the cylinder head side closest to said second intake valve and extending substantially in transverse relation to the longitudinal median plane of the engine as far as said first intake valve, a second inlet port designed as a spiral duct originating at said side of said cylinder head and extending substantially in the longitudinal direction of the engine as far as said second intake valve, the combination of the following features: said first inlet port being designed as an inclined duct having a straight line axis extending approximately in a direction to and intersecting with the axis of said first intake valve; said second inlet port extending from said side of the cylinder head and changing with a bend into a direction approximately parallel to the longitudinal median plane of the engine; an inner wall of said second inlet port changing tangentially into the guide bearing of said second intake valve and defining a duct tongue in conjunction with said guide bearing;