The Vaporizing Of Paraffin for High-Speed Motors
(Electric Ignition Type)

PETROL CARBURETTORS. 17 There is yet another method, as shown in Fig. 9, for raising the fuel supply from a low level service tank to a constant level carburettor cistern. According to this rather ingenious device (Olds) the suction effect produced partly by the use of an extra ]ong choke-tube, n, is utilized to actuate a small pulsator pump, p, through the duet y and suction pipe /, by which means a flow of fuel is raised at each suction stroke—i.e., provided the throttle h is open—along the pipe /, the pulsator val ve v being drawn up to its seat during this period, thereby closing down all suction effect along the pipe iv, which then takes the place of an overflow from the cistern r to the main tank k, and in this manner maintains a constant level in the cistern. The method now most generally adopted in all petrol and paraffin motors is some form of float-feed valve con- troller! constant level cistern, the earliest application of which for this purpose was made by the writer in a three- cylinder launch motor made in 1888-89 ; the float cistern for this, of the hinged type as shown in Fig. 10, was not dissimilar to the form of float cistern now used by many manufacturers of stationary paraffin and petrol motors, and also in a number of automobiles of American construction in somewhat modified form, the principal difference being the substitution of a cork float in place of the spun coppér ball (vide Fig. 21). The hinged float, also adopted in the Binks petrol-paraffin carburettors, possesses points ahead of the more conipact form of cylindrical float cisterns (vide Figs. 11 to 15), such as more generally used in British and European motors for road cars and motor boats, but is not so conipact. Of the five forms of cylindrical float cisterns shown. 2