Internal combustion engine

An internal combustion engine, comprising:

• a cylinder block within which at least one cylinder bore is defined;
• a cylinder head mounted on the cylinder block;
• a piston mounted for reciprocable movement in each bore;
• an inlet valve movably mounted in the cylinder head for each cylinder bore;
• a variable geometry chamber defined by the cylinder head, the cylinder bore and the piston;
• inlet means for each cylinder bore through which a combustible mixture is introduced tangentially into the variable geometry chamber, said inlet means cooperating with its respective inlet valve to generate a swirling motion of the combustible mixture within its respective variable geometry chamber;
• a recess formed in at least one of each piston and adjacent cylinder head to define at the end of the compression stoke of the associated piston a combustion chamber having a substantially smaller cross-section than the cylinder bore;
• an exhaust valve movably mounted in the cylinder head for each cylinder bore;
• outlet means for each cylinder bore, said outlet means cooperating with its respective exhaust valve for discharging exhaust gas from the combustion chamber;
• an ignition device in each combustion chamber for producing ignition therein;
• and
• a spoiling device within each combustion chamber for breaking up the swirling motion of the combustible gas at or near the end of the associated piston's compression stroke so as to produce turbulence in the form of small eddies.