Patent GB-423778-A (GB)
Title: Regulating means for carburettors
IPC: F02M1/04
Filed: 1934-05-26
Abstract: 423,778. Spray carburetters. MENNESSON, M. L., 190, Avenue de Neuilly, Neuilly-sur-Seine, France. May 26, 1934, Nos. 15764 and 15765. Convention dates, Nov. 9, 1933 and Dec. 4, 1933. [Class 7 (iii)] In carburetters, such as described in Specifications 357,310 and 420,715 provided with auxiliary carburetting means for effecting the starting of the engine and running when cold, and wherein a thermally actuated device serves to bring the auxiliary carburetting means into or out of action, or to regulate the mixture produced by the auxiliary means, the control is effected by a deformable or movable element the position of which depends on the differential action of pressures exerted on its faces, one of the faces being subjected to the action of a fluid the pressure of which is modified by the thermally actuated device subject to engine temperature, while the other face is subjected to engine suction, atmospheric pressure or a combination of the two. The invention is described in the Specification with reference to twenty-four independent Figures which show different forms and arrangements of the deformable or movable element and the valves actuated thereby for bringing the auxiliary carburetter into and out of action, and for actuating the regulating means of such carburetter. The first ten Figures refer to the means for bringing into and putting out of action, and the remaining Figures to means either in place of, or in addition to these for controlling the auxiliary carburetter. The following are examples of the constructions described. The carburetter, Fig. 1, has a float chamber 1, main nozzle 3, idling nozzle 2 and an auxiliary carburetting device comprising a mixing chamber 12 into which fuel is discharged by a nozzle 10 fed from a well 9 open to atmosphere and supplied through a calibrated orifice 8. The mixing chamber 12 communicates with the induction passage 5 through an aperture 15 adapted to be controlled by a valve 14 carried by a diaphragm 16. The chamber 12 is open to atmosphere at 13, and the chamber 17, on the other side of diaphragm 16, is connected by a pipe 18 with the induction passage, and with the atmosphere by a pipe 19 the open end of which is adapted to be controlled by a thermal strip 20 attached to the exhaust pipe 21. When the engine is cold the end of the pipe 19 is closed, and suction is exerted in chamber 17 to move valve 14 and open the aperture 15. As the engine warms up, strip 20 expands, air enters pipe 19 and destroys the suction in 17, and the aperture is closed. In a modification, Fig. 2, a second, spring-loaded, valve 23 is provided to prevent a pressure-surge from the engine from producing sudden movement of diaphragm 16. In Figs. 3, 4, (not shown), the pipe 18 is dispensed with and suction is transmitted to the space 17 through an axial bore in the valve 14 or in a piston which combines the functions of the valve 14 and diaphragm 16. The pipe 19 may be arranged to be open in the cold condition, suction being transmitted to the inner face of diaphragm 16, Fig. 5. In a modification this arrangement is combined with the spring-loaded valve of Fig. 2. In Fig. 9, the diaphragm 16 is adapted to be moved by expansion of a fluid in an enclosed space 26 heated by the engine, the other face of the diaphragm being subjected either to vacuum or, in a modification, to atmospheric pressure only. In Fig. 11, the diaphragm actuates a needle valve 28 controlling the fuel nozzle 29 of the auxiliary carburetter. In Fig. 12, the two controls are employed together, the diaphragm 16 actuating the outlet valve 14 of the auxiliary carburetter and a piston 31 actuating a needle valve 28 which controls the inlet 29 to the fuel well 9 or, in a modification, an additional inlet thereto. The space above piston 31 is in communication with atmosphere by a pipe 30 adapted to be controlled by the same thermal strip 20 that controls the pipe 19. In Fig. 14, (not shown), the piston 31 actuates a movable upper part of the fuel tube 10 of Fig. 1, to vary the head under which fuel is delivered. In Fig. 15, (not shown), the diaphragm actuates a valve controlling the entry of air to the fuel passage of the auxiliary carburetter. In Figs. 17, 18, (not shown), the piston 31 of Fig. 12, in addition to regulating the auxiliary carburetter serves also as the valve for bringing it into and out of action. In Fig. 21, the piston 31 carries a tube 13 into which the auxiliary nozzle 29 delivers, the tube being flared at its lower end, loaded by a spring 36, and provided with extra air ports 38, 39 adapted to come into action to weaken the mixture as the temperature rises. In Fig. 22, (not shown), the piston 31 of Fig. 12, is replaced by a diaphragm which, together with the diaphragm 16 is subjected to the pressure of the fluid in a heated enclosed space as in Fig. 9. In modifications, Figs. 23, 24, (not shown), a perforated fixed diaphragm is interposed between the inner face of the movable diaphragm and the suction passage to ensure that only a part of the suction is transmitted to the movable diaphragm.