Carburetors

In carburators for internal combustion engines comprising two articulate venturi blocks which in combination produce between them a variable aperture, said blocks being mounted in the intake path of the carburator and being combined with a diaphragm control device which actuates a feeding needle valve located inside a feed nozzle connected with a constant level float chamber providing fuel, the improvement

• wherein said two variable aperture venturi blocks are similarly shaped and are pivotally mounted on two spaced parallel pivoting axes so as to swing inwardly and downwardly and vice-versa, describing an arc of approximately 90 degrees, said venturi blocks being so shaped that a small aperture is formed between them when in their elevated position, said aperture widening as the blocks swing inwards and downwards on account of the particular configuration given to said blocks, said aperture being located directly above said feed nozzle;
• wherein said feed nozzle stands vertically and the wall of the lower end of said feeding nozzle tapers downwards and displays around its tapered periphery a plurality of spraying outlets, the bore of said feed nozzle above said tapering lower end being substantially cylindrical, but tapering internally into a narrow passage and tapering out again, thus forming two small chambers, one above and one below said narrow passage, said lower chamber being located immediately above the final lowermost tapering, wherein said plurality of spraying outlets is located;
• and
• wherein said feeding needle valve includes a downwardly tapered feeding needle freely mounted in said feed nozzle and a generally cylindrical seat internally mounted in threaded relationship -- allowing vertical shifting -- on the lower tapered end of said feed nozzle, said feeding needle being capable of abutting the upper end of said cylindrical seat.