GB655426A - Improvements in or relating to carburettors for internal combustion engines - Google Patents

Abstract

655,426. Spray carburetters. CARBONARO, M. C. Aug. 14, 1947, No. 22646, 22647 and 22648. Convention dates, Aug. 14, 1946, Oct. 1, 1946, and July 22, 1947. Addition to 652,671. [Class 7(iii)] In a modification of the carburetter of the parent Specification, which comprises a nozzle 19a delivering emulsified fuel into a byepass 11a connected to Venturis 6a, 8a, above and below the throttle valve 7a and containing restrictions 12a, 13a, the delivery of the nozzle 19a is reduced at partthrottle operation. In Fig. 1 the orifice 13a is controlled by a needle 17a actuated by a capsule 16a subjected to the suction in a Venturi 18a coaxial with the Venturi 8a. The high suction below the throttle valve when it is closed causes the needle 17a to obstruct the orifice 13a, thus reducing the suction at the nozzle 19a and hence the delivery therefrom. The needle 17a may control the fuel jet 9a, and may be operated mechanically from the throttle valve 7a, Enrichment at starting is produced by a valve 22a actuated to obstruct the upper orifice 12a by hand or by means of a thermometric member sensitive to the temperature of the engine or of the cooling water. The valve 22a may also be actuated from the throttle valve to produce enrichment at full power. In Fig. 3 the Venturi 18c is fed by a compressor 21c and the float chamber 7c is connected through a cock 24c with a chamber 17c connected by restrictions 16c, 20c with the inlet pipe and atmosphere respectively so that a suction is produced therein. The emulsifying air for the nozzle 19c is obtained from the float chamber through a pipe 23c. The fuel jet 9c is fed through orifices 25c, 26c, a valve 27c connected to the throttle valve closing the orifice 26c to reduce the fuel supply at slow running. Temporary enrichment at starting is obtained by turning the cock 24c to disconnect the float chamber from the suction in chamber 17c. In a modification the cock 24c is omitted and the chamber 17c is connected to the throat of the Venturi 18c, enrichment at starting being obtained by obstructing the upper orifice 12c as in Fig. 1.