GB459095A - Improvements relating to carbureters for internal combustion engines - Google Patents

Abstract

459,095. Spray carburetters. GRANVILLE, B., 17, John Street, New York, U.S.A. March 30, 1936, No. 9339. [Class 7 (iii)] A spraying tube extending into the mixing chamber and communicating with a fuel supply, is reciprocated within a stationary nozzle member positioned at the entrance to the mixing chamber and limiting the area of that entrance, by mechanism controlled by the velocity of the air passing through the air intake, the displacement of the spraying tube in the mixing chamber maintaining the proportion of air and fuel substantially constant. The carburetter comprises an air inlet 1 leading to a Venturi 21 and mixing chamber 4, and a fuel chamber 3 containing a float 32 and communicating with a constant level chamber 2 containing a float 8. A stationary tubular member 25 limits the entrance passage to the Venturi 21 and houses a spraying tube 26 mounted on a lever 30 linked at its end to the float 32, the fuel discharged being aerated through an inner pipe 34 in communication with a controlled inlet 41, Fig. 10, through a passage 42. A pitot tube 51, adjustably positioned in the air inlet 1 transmits pressure through a passage 53 and U-tube 58 to the top of the constant level chamber 2 and this pressure, which varies with the velocity of the air in the air inlet, drives fuel into the chamber 3 to raise or lower the float 32, the float keeping the spraying tube 26 at the correct position in the Venturi 21. An adjustable air vent 44 is closed by the float 32 at the top of its lift. Fuel for idling is drawn from the chamber 3 through a vertical passage 77 to a plug 66 formed with two small mixing chambers opening, the one above the other, into the mixing chamber adjacent the throttle valve 6. A projection 78 on the valve blocks the lower opening when the valve 6 is closed, but uncovers it when the valve is opened slightly for fast idling.