Patent ID: 7357377
Filing Date: 2008-04-15
Classification: F02B,F02M,Y10S

Abstract:
1. A carburettor for supplying fuel into the inlet duct of an internal combustion engine, the inlet duct being divided by a dividing wall over at least part of its length into two inlet passages, a rich passage and a lean passage, the carburettor including a fuel chamber and defining a flow duct divided by a substantially planar partition into a rich duct and a lean duct which communicate, in use, with the rich passage and the lean passage, respectively, the partition affording an aperture in which a substantially planar butterfly valve is pivotally mounted, at least one fuel supply orifice communicating with the fuel chamber and with the rich duct at a position opposite to the aperture, the butterfly valve being pivotable between an open position, in which the flow duct is substantially open and the aperture is substantially closed and substantially all of the fuel flowing out of the fuel supply orifice flows into the rich duct, and a closed position, in which the flow duct is substantially closed and the aperture is substantially open and the fuel flowing out of the fuel supply orifice flows into both the rich and lean ducts, characterised by an air bleed idle system comprising an idle fuel supply orifice communicating with the rich and lean ducts and with the fuel chamber and with atmosphere, whereby, under idling operation of the engine, an air fuel mixture is induced into the rich and lean ducts through the idle fuel supply orifice.