GB652883A - Improvements in or relating to fuel supply systems for multi-cylinder internal combustion engines - Google Patents

Abstract

652,883. Spray carburetters. CARTER CARBURETOR CORPORATION. Feb. 24, 1948, No. 5516. Convention date, July 31, 1942. [Classes 7(iii) and 7(vi)] In a multicylinder engine the cylinders are arranged in groups connected to separate intake manifolds 10, 11, Fig. 1, fed by twin carburetters 13, 14 with fuel nozzles fed respectively from passages 16, 17, Fig. 2, to which fuel is metered through orifices 20, 21 controlled by metering valves 39, 43 operated by suction to close the orifice 20 to put the carburetter 13 and manifold 10 out of action at idling, and to close both orifices at a higher suction, e.g. at overrunning. The valves 39, 43 carry small magnets 54 to provide a snap-action opening and closing, and the valve stems 18, 19 are connected to a rod 33, Fig. 3, operated by a spring-loaded piston 34 actuated by the suction downstream of the throttle valve transmitted through a passage 37. When the throttle valve is closed for idling, the suction, e.g. 10 in. mercury, moves piston 34 against a spring 38 and carries the valves 39, 43 downwards so that the valve 39 closes the orifice 20 and puts the manifold 10 out of action. At a higher suction, e.g. 18 inch mercury during overrunning, a lost-motion connection between the valve stem 18 and the rod 33 allows the piston 34 to compress a second spring 55 and move down further to cause valve 43 to close orifice 21 and put the manifold 11 also out of action. The carburetters may include ari automatic choke mechanism provided with means holding the throttle valve slightly open at starting and warming up. In this position an arm 49, Figs. 2 and 3, rotated by a link from the throttle valve operating mechanism, raises the rod 33 and opens the valves 39, 43 so that both carburetters are in operation at starting. Acceleration pumps may be included in the carburetters. Specifications 472,090 and 531,244 [Group XXXV], are referred to.