| 摘要 |
The invention relates to a method for controlling the working cycle of a four-stroke internal combustion piston engine with supercharging and direct fuel injection into each cylinder and with at least one inlet valve and one exhaust valve for each cylinder. The method involves opening the exhaust valve for a second time during each working cycle, in addition to holding the valve open (9-10-11) during the exhaust expulsion stroke. According to the invention the exhaust valve is opened and closed (4-5) for the second time during the compression stroke, the valve being opened (4) when the piston is located in a first predetermined position (D) at a distance from the lower dead centre piston position (C) and being closed (5) when the piston is located in a second predetermined position (E) at a distance from the lower dead centre piston position (C) greater than the first predetermined position (D). …<??>The inlet valve is closed during the inlet stroke, so that expansion of the air in the cylinder at full load subsequent to closing the valve is effected to or beneath the pressure in the exhaust system. |
