METHOD FOR CONTROLLING THE RELEASE OF FUEL VAPOUR FROM A TANK VENTILATION SYSTEM

摘要

The invention relates to a method for controlling the release of fuel vapour from a tank ventilation system (6), preferably into an individual cylinder inlet port (4) on an internal combustion engine (1), whereby a control valve (10) synchronises the release of the fuel vapour into the inlet port with the inlet stroke of the corresponding internal combustion engine cylinder and the opening time point of the control valve may be varied. It is preferred that, for the control or dosing of large amounts of fuel vapour, the opening time point lies in a range where a large vacuum exists in the inlet port, whilst for the control or dosing of small amounts of fuel vapour, the opening time point lies in a range where a low vacuum exists in the inlet port. The closing time point of the control valve is also variable and said valve is not opened when an overpressure exists in the inlet port. Viewed over several consecutive working cycles of a cylinder, beginning with an initial release of fuel vapour into the inlet port, the opening timepoint for successive working cycles is displaced increasingly from the regions of low vacuum to regions of high vacuum.