| 摘要 |
In order to supply pressurised EGR in a multi-cylinder internal combustion engine, especially a supercharged or turbocharged engine, the opening of an exhaust port throttle valve 14 is reduced to increase the peak of the rising exhaust back pressure within the throttled exhaust port 12 during the exhaust stroke of the cylinder sufficiently to drive cyclically a pulse of pressurised exhaust gases at an instantaneous pressure higher than the mean gas pressure of the engine exhaust system from the throttled exhaust port 12 via a non-return EGR charging valve 16 located in an EGR charging pipe 18 through to an EGR gas chamber 20. A continuous flow of EGR gas is then delivered from the EGR gas chamber 20 into the intake system 26 of the engine via an EGR dispensing pipe 22. A flow regulating valve 24 may be provided in the EGR dispensing pipe 22. An additional EGR pipe (19, fig.2) may be provided to connect the main exhaust system 28 to the EGR gas chamber 20 via a non-return valve (17). |
