GB159506A - Improvements in and relating to carburetters for internal combustion engines - Google Patents

Abstract

159,506. Pifarre, J. Feb. 26, 1920, [Convention date]. Void [Published under Sect. 91 of the Act]. Spray carburettors.-A mixture of constant proportions is obtained by providing a suctionactuated valve in or adjacent to the nozzle, the lifting of the valve either decreasing the fuel supply or, when both air and fuel are supplied to the nozzle, increasing or decreasing such air supply. In the form shown in Fig. 3, fuel is supplied to the nozzle 12<a> during slow-running through ducts 18, 19, the duct 18 being closed by a ball valve 17 when the suction increases. In modifications, (1) a plug beneath the nozzle is provided with a central uncontrolled fuel duct and with two outer ducts, the fuel supply to which is cut off by ball valves as the suction rises; (2) a short pipe having a spherical head provided with three fuel outlets is mounted in the fuel inlet pipe beneath the nozzle, two of the outlets being cut off when the tube is lifted by suction into contact with the bottom of the nozzle; (3) the nozzle bore is coned at the base and the fuel supply is controlled by a ball valve 23, Fig. 4, which is provided with a fuel passage 13b and with a stem 12b provided at its upper end with a ball 22 upon which the suction acts. Fig. 7 shows a construction in which air is supplied through the central bore of the nozzle when the suction is sufficient to raise a ball valve 17<c>, the fuel being supplied through ducts 18<c>, 19<c>. In modifications, (1) the valve 17<c> is provided with a stem and ball as shown in Fig. 4, and the air inlet pipe is U-shaped to trap leaking fuel, (2) the valve is situated in a conical portion of an inverted U-shaped air pipe which discharges into the base of a nozzle fed with fuel through a calibrated orifice. The ball valve may have holes bored through it to allow the passage of a small amount of air or to allow fuel which has leaked past the valve to be used up in starting. In a further modification, air is supplied to the nozzle at low speeds through a central pipe 26, Fig. 5, the air supply being cut off at high suctions by a ball valve 27 which closes the end of the pipe 26.