METHOD OF REDUCING EMISSIONS IN THE EXHAUST GASES OF AN INTERNAL COMBUSTION ENGINE

摘要

The invention relates to a method of reducing emissions in the exhaust gases of an internal combustion engine (1) which comprises at least one cylinder (2) to which an air/fuel mixture is supplied when a crankshaft (3) of the internal combustion engine (1) is to be made to rotate, at least one inlet valve (4), at least one exhaust valve (6), control members (8) for controlling the opening and closing of the inlet and exhaust valves (4, 6), and a piston (10) reciprocating between a top dead-centre position and a bottom dead-centre position in the cylinder (2). The method comprises the following steps: an air/fuel mixture with lambda value greater than 1 is supplied to the cylinder (2), the internal combustion engine (1) is controlled so that it works at high load, and the inlet valve (4) is controlled so that it opens after the piston (10) has passed the top dead-centre position. According to an embodiment of the invention, the internal combustion engine (1) is controlled so that the crankshaft (3) rotates at an essentially constant speed within the range 1000 - 2000 rpm.