Fuel is admitted through pipe 1 to chamber 2 containing float 3, which operates needle valve 4. From the float chamber, fuel is delivered partly through channel a to economizer 5, while the main part of the fuel passes through jet 6 into venturi 7 where it mixes with air under pressure admitted through jet 13. The chamber of economizer 5 is divided into two compartments by diaphragm 8. The compartment to the right of the diaphragm is connected to the space beyond throttle valve 9 which turns about fixed axis A. At medium engine loads, owing to vacuum in the right-hand compartment of the economizer, diaphragm 8 is bent to its extreme right position, closing valve 10. In going over to full load of the engine, the vacuum to the right of the diaphragm is reduced to the extent that the diaphragm is bent by spring 11 to its extreme left position, opening valve 10. At this, additional fuel is supplied to the venturi through jet 12 of the economizer.
$4250$CHP,Rg$