GB532428A - Improvements in and relating to carburettors for internal combustion engines - Google Patents

Abstract

532,428. Spray carburetters. SOC. GENERALE DES CARBURATEURS ZENITH. Aug. 30, 1939, No. 24899. Convention date, Sept. 1, 1938. [Class 7 (iii)] A carburetter receiving air from a supercharger is provided with means for varying the richness of the mixture by a manometric device subjected to atmospheric pressure or to the pressure in the supercharger intake, and arranged to come into action when the said pressurefalls below a predetermined value, or when the aircraft has reached a rated height. A valve 18 controlling the flow of fuel from a float chamber- 6 to the nozzle 4 is acted on by a capsule 14 in a chamber 15, the float chamber being subjected to supercharger pressure by a pipe 9. The chamber 15 is shown connected by a pipe 16 to the intake 3 of the supercharger 2. The means whereby the capsule does not adjust the richness until the rated altitude is reached, may comprise the provision of lost motion between the capsule and the end 21 of the valve 18, as shown in Fig. 1, or the valve may be formed with a cylindrical portion which does not alter the richness during the initial movement of the capsule ; or the needle valve 18 may be replaced by a sliding tube with perforated walls, or be actuated by a cam with a circular inactive portion. In a modification, Fig. 2, the float chamber is subjected to a vacuum through a passage 30 which is controlled by a valve 31 actuated by the capsule, the pipe 9 having a calibrated orifice 27. The valve 31 may also be formed with a cylindrical portion, or be replaced by a perforated tube. A relay device may be interposed between the capsule and the fuel-control valve.