Two-stage carburettor for combustion engines

摘要

Two-stage carburettor comprising a primary bore, which has a fixed inlet part, a secondary bore with an inlet part whose cross-section is variable by means of a piston valve and a connecting mechanism which can open and close the secondary throttle valve as a function of the primary throttle valve in order to allow a gentle transitional and output characteristic to be obtained over the entire engine characteristic curve. The ratio of the cross-sectional area of the secondary bore to that of the primary bore is so designed that it is not less than 70:30. The intake ducts behind the primary and the secondary bore are separated and connected to the appropriate cylinders of an engine. In the vicinity of the inlet valve of the appropriate cylinders inside each branch of the secondary bore there is a corresponding secondary throttle valve. <IMAGE>