Supplying fuel to internal combustion engines

A carburettor for an internal combustion engine including a duct connectable to a combustion charge inlet of the engine and having opposed internal wall portions which are parallel,

• a. a vacuum inducing vane pivotally mounted about an offset pivot axis within the duct near the upstream end thereof, being biased by biasing means towards a closed position to impede airflow through the duct and being displaceable against the biasing means by airflow through the duct, thereby, during operation, to create a negative pressure downstream thereof;
• b. a fuel control vane mounted to be displaceable by the airflow through the duct;
• c. a control valve and a regulating valve, the valves being connected in series and being located transversely to the axis of the duct in opposed end to end relationship, the control valve being connectable to a fuel source and the regulating valve having a fuel outlet for feeding fuel into the duct, said outlet being located downstream of the vacuum inducing vane and within the concentrated airstream resulting from the airflow deflected by the vacuum inducing vane;
• d. means linking the regulating valve to the fuel control vane so that the regulating valve is controllable in response to movement of the fuel control vane;
• e. a butterfly valve in the duct operable by a throttle linkage and means operably connecting the butterfly valve with the control valve.