GB580340A - Improvements in or relating to carburettors for internal-combustion engines - Google Patents

Abstract

580,340. Spray carburetters. BEDALE, P. W. July 3, 1944, No. 12670. [Class 7 (iii)] In order to supply increased fuel to an engine momentarily as the throttle is opened a carburetter has fuel delivered to a supply chamber 12, communicating through a jet (not shown) with a chamber 13 leading to the induction pipe, through a port controlled by a valve 21 actuated by a diaphragm 11, normally operated to close the valve by the pressure difference between chambers 12 and 13 and connected to a piston 16 operated by a throttle actuated pump 17. When the throttle control is opened a pump piston 19, which is connected to it by a rod 20, moves into a cylinder 17 and forces fuel through a conduit 18 into a cylinder 15, increasing pressure therein and loading diaphragm 11, through piston 16, so that valve 21 is opened. The pressure in the supply chamber 12 is also increased and results in an increased flow of fuel to the engine. When the throttle movement ceases, the pressure in the cylinder 15 is reduced by leakage past the piston 16 until it is equal to the pressure in, conduit 14. An automatic valve 22 is mounted on the pump piston 19 and opens when the piston moves out of the cylinder 17, when the throttle is closed, so that the cylinder refills with fuel. An engine driven governor 10 may be arranged to bias the valve 21 towards its open position.