GB124933A - Improvements in Carburettors for Internal Combustion Engines. - Google Patents

Abstract

124,933. Holley Bros. Co., and Copson, T. C. April 27, 1918. Spray carburettors.-In a spray carburettor, the main nozzle dips into a fuel well supplied through a restricted orifice, and an air passage communicates with the well and surrounds a tube projecting into the well below the fuel level, such tube constituting part of a by-pass the outlet of which into the induction pipe is wider than the throttle edge so as to be divided therebv when the throttle is in the closed position. The carburettor comprises an horizontal main air passage A‹ and a depending vertical branch A' which is closed by a cap C and is divided into chambers A<2>, A<3> by a plug A<4> containing an aperture A<5> controlled by a needle valve D, such aperture constituting the restricted orifice through which fuel enters the chamber A<3> from the float chamber B. A main nozzle E leads from the auxiliary chamber A<3> to the main air passage A<0>, and a tube G, with lateral passages leading to a groove G<2> in a plug G<1> by which it is adjusted, leads by way of a passage A<9>, Fig. 2, to a by-pass nozzle K the outlet orifice K<1> of which is wider than the edge of the throttle valve L. The passage A<9> may be open to the atmosphere at G<4>, and the fuel well A<3> is in communication with the atmosphere through the annular passage A<7> and duct N. The nozzle E is provided at its lower end, which is just below the normal fuel level, with a plug E<1> having a bore E<2>, Fig. 4, preferably of Venturi form, and lateral apertures E<4> admit air to the fuel when the lower end of the bore E<2> is submerged, but air may also enter through this bore by the fuel level in the chamber A<3> falling below the bottom of the plug E<1>. In a modification, the valve-controlled aperture AS is replaced by an uncontrolled orifice in a tube which may be interchanged with others having orifices of different size and having lateral inlet apertures and forced against the plug A<4> by a spring washer between the lower end of the tube and the cap C. The annular space between the nozzle E and plug E<1>, Fig. 4, may be replaced by helical or straight slots cut in the outer wall of the plug.