Overflow device for carburetor

1. Field of the Invention To provide an overflow device for suppressing undue emission of fuel from an overflow pipe which can be produced with a simple structure at a low cost, and can be simply applied also to any existing carburetors. An overflow device for a float type carburetor includes an overflow pipe having an upper end opening exposed to a space in a float chamber defined above a constant fuel level in the float chamber, and a shield member arranged above the constant fuel level for forming a shielded space in the vicinity of the upper end opening. The shield member has a side wall vertically extending above and below the upper end opening, a top wall positioned above the upper end opening, and a bottom wall positioned below the upper end opening. The bottom wall is formed with fuel holes for allowing the fuel to flow into and out of the shielded space. The side wall is formed with small vent holes capable of suppressing the entry of the fuel into the shielded space.