Carburettor with auxiliary throttle flap - has sprung diaphragm pneumatic regulator operating series of taper needles to regulate fuel flow for each cylinder

摘要

The carburettor air intake has an auxiliary throttle flap upstream of the main throttle. The auxiliary throttle opens automatically and progressively corresp. to air intake vol. and its pivot shaft is mechanically linked to a fuel metering unit in the float chamber which has a number of taper needles. Each needle is able to vary the cross section of a feed pipe leading to a pneumatic regulator on each cylinder intake port. Each pneumatic regulator has a sprung diaphgram dividing a housing into two parts. The diaphragm movement is transferred to a needle valve to regulate the fuel pressure outlet. Each diaphragm chamber is connected to a depression source between the auxiliary air flap and the main throttle valve.